diff --git a/.cirrus.tasks.yml b/.cirrus.tasks.yml
index 92057006c9309..1a366975d824f 100644
--- a/.cirrus.tasks.yml
+++ b/.cirrus.tasks.yml
@@ -938,14 +938,11 @@ task:
   # - Don't use ccache, the files are uncacheable, polluting ccache's
   #   cache
   # - Use -fmax-errors, as particularly cpluspluscheck can be very verbose
-  # - XXX have to disable ICU to avoid errors:
-  #   https://postgr.es/m/20220323002024.f2g6tivduzrktgfa%40alap3.anarazel.de
   ###
   always:
     headers_headerscheck_script: |
       time ./configure \
         ${LINUX_CONFIGURE_FEATURES} \
-        --without-icu \
         --quiet \
         CC="gcc" CXX"=g++" CLANG="clang-16"
       make -s -j${BUILD_JOBS} clean
diff --git a/.git-blame-ignore-revs b/.git-blame-ignore-revs
index 8048afd1a80fa..f83e2fc658664 100644
--- a/.git-blame-ignore-revs
+++ b/.git-blame-ignore-revs
@@ -14,6 +14,15 @@
 #
 # $ git log --pretty=format:"%H # %cd%n# %s" $PGINDENTGITHASH -1 --date=iso
 
+1d1612aec7688139e1a5506df1366b4b6a69605d # 2025-07-29 09:10:41 -0400
+# Run pgindent.
+
+73873805fb3627cb23937c750fa83ffd8f16fc6c # 2025-07-25 16:36:44 -0400
+# Run pgindent on the changes of the previous patch.
+
+9e345415bcd3c4358350b89edfd710469b8bfaf9 # 2025-07-01 15:23:07 +0200
+# Fix indentation in pg_numa code
+
 b27644bade0348d0dafd3036c47880a349fe9332 # 2025-06-15 13:04:24 -0400
 # Sync typedefs.list with the buildfarm.
 
diff --git a/config/llvm.m4 b/config/llvm.m4
index fa4bedd9370fc..9d6fe8199e364 100644
--- a/config/llvm.m4
+++ b/config/llvm.m4
@@ -4,7 +4,7 @@
 # -----------------
 #
 # Look for the LLVM installation, check that it's new enough, set the
-# corresponding LLVM_{CFLAGS,CXXFLAGS,BINPATH} and LDFLAGS
+# corresponding LLVM_{CFLAGS,CXXFLAGS,BINPATH,LIBS}
 # variables. Also verify that CLANG is available, to transform C
 # into bitcode.
 #
@@ -55,7 +55,7 @@ AC_DEFUN([PGAC_LLVM_SUPPORT],
 
   for pgac_option in `$LLVM_CONFIG --ldflags`; do
     case $pgac_option in
-      -L*) LDFLAGS="$LDFLAGS $pgac_option";;
+      -L*) LLVM_LIBS="$LLVM_LIBS $pgac_option";;
     esac
   done
 
diff --git a/config/prep_buildtree b/config/prep_buildtree
index a0eabd3dee288..e148535ac112e 100644
--- a/config/prep_buildtree
+++ b/config/prep_buildtree
@@ -22,18 +22,14 @@ sourcetree=`cd $1 && pwd`
 
 buildtree=`cd ${2:-'.'} && pwd`
 
-# We must not auto-create the subdirectories holding built documentation.
-# If we did, it would interfere with installation of prebuilt docs from
-# the source tree, if a VPATH build is done from a distribution tarball.
-# See bug #5595.
-for item in `find "$sourcetree" -type d \( \( -name CVS -prune \) -o \( -name .git -prune \) -o -print \) | grep -v "$sourcetree/doc/src/sgml/\+"`; do
+for item in `find "$sourcetree"/config "$sourcetree"/contrib "$sourcetree"/doc "$sourcetree"/src -type d -print`; do
     subdir=`expr "$item" : "$sourcetree\(.*\)"`
     if test ! -d "$buildtree/$subdir"; then
         mkdir -p "$buildtree/$subdir" || exit 1
     fi
 done
 
-for item in `find "$sourcetree" -name Makefile -print -o -name GNUmakefile -print | grep -v "$sourcetree/doc/src/sgml/images/"`; do
+for item in "$sourcetree"/Makefile `find "$sourcetree"/config "$sourcetree"/contrib "$sourcetree"/doc "$sourcetree"/src -name Makefile -print -o -name GNUmakefile -print`; do
     filename=`expr "$item" : "$sourcetree\(.*\)"`
     if test ! -f "${item}.in"; then
         if cmp "$item" "$buildtree/$filename" >/dev/null 2>&1; then : ; else
diff --git a/config/programs.m4 b/config/programs.m4
index 0ad1e58b48d6b..e57fe4907b844 100644
--- a/config/programs.m4
+++ b/config/programs.m4
@@ -284,20 +284,26 @@ AC_DEFUN([PGAC_CHECK_STRIP],
 
 AC_DEFUN([PGAC_CHECK_LIBCURL],
 [
+  # libcurl compiler/linker flags are kept separate from the global flags, so
+  # they have to be added back temporarily for the following tests.
+  pgac_save_CPPFLAGS=$CPPFLAGS
+  pgac_save_LDFLAGS=$LDFLAGS
+  pgac_save_LIBS=$LIBS
+
+  CPPFLAGS="$CPPFLAGS $LIBCURL_CPPFLAGS"
+  LDFLAGS="$LDFLAGS $LIBCURL_LDFLAGS"
+
   AC_CHECK_HEADER(curl/curl.h, [],
 				  [AC_MSG_ERROR([header file <curl/curl.h> is required for --with-libcurl])])
+
+  # LIBCURL_LDLIBS is determined here. Like the compiler flags, it should not
+  # pollute the global LIBS setting.
   AC_CHECK_LIB(curl, curl_multi_init, [
 				 AC_DEFINE([HAVE_LIBCURL], [1], [Define to 1 if you have the `curl' library (-lcurl).])
 				 AC_SUBST(LIBCURL_LDLIBS, -lcurl)
 			   ],
 			   [AC_MSG_ERROR([library 'curl' does not provide curl_multi_init])])
 
-  pgac_save_CPPFLAGS=$CPPFLAGS
-  pgac_save_LDFLAGS=$LDFLAGS
-  pgac_save_LIBS=$LIBS
-
-  CPPFLAGS="$LIBCURL_CPPFLAGS $CPPFLAGS"
-  LDFLAGS="$LIBCURL_LDFLAGS $LDFLAGS"
   LIBS="$LIBCURL_LDLIBS $LIBS"
 
   # Check to see whether the current platform supports threadsafe Curl
diff --git a/configure b/configure
index 16ef5b58d1a87..507a2437c3308 100755
--- a/configure
+++ b/configure
@@ -5194,7 +5194,7 @@ fi
 
   for pgac_option in `$LLVM_CONFIG --ldflags`; do
     case $pgac_option in
-      -L*) LDFLAGS="$LDFLAGS $pgac_option";;
+      -L*) LLVM_LIBS="$LLVM_LIBS $pgac_option";;
     esac
   done
 
@@ -9436,12 +9436,12 @@ fi
   # Note the user could also set XML2_CFLAGS/XML2_LIBS directly
   for pgac_option in $XML2_CFLAGS; do
     case $pgac_option in
-      -I*|-D*) CPPFLAGS="$CPPFLAGS $pgac_option";;
+      -I*|-D*) INCLUDES="$INCLUDES $pgac_option";;
     esac
   done
   for pgac_option in $XML2_LIBS; do
     case $pgac_option in
-      -L*) LDFLAGS="$LDFLAGS $pgac_option";;
+      -L*) LIBDIRS="$LIBDIRS $pgac_option";;
     esac
   done
 fi
@@ -9666,12 +9666,12 @@ fi
   # note that -llz4 will be added by AC_CHECK_LIB below.
   for pgac_option in $LZ4_CFLAGS; do
     case $pgac_option in
-      -I*|-D*) CPPFLAGS="$CPPFLAGS $pgac_option";;
+      -I*|-D*) INCLUDES="$INCLUDES $pgac_option";;
     esac
   done
   for pgac_option in $LZ4_LIBS; do
     case $pgac_option in
-      -L*) LDFLAGS="$LDFLAGS $pgac_option";;
+      -L*) LIBDIRS="$LIBDIRS $pgac_option";;
     esac
   done
 fi
@@ -9807,12 +9807,12 @@ fi
   # note that -lzstd will be added by AC_CHECK_LIB below.
   for pgac_option in $ZSTD_CFLAGS; do
     case $pgac_option in
-      -I*|-D*) CPPFLAGS="$CPPFLAGS $pgac_option";;
+      -I*|-D*) INCLUDES="$INCLUDES $pgac_option";;
     esac
   done
   for pgac_option in $ZSTD_LIBS; do
     case $pgac_option in
-      -L*) LDFLAGS="$LDFLAGS $pgac_option";;
+      -L*) LIBDIRS="$LIBDIRS $pgac_option";;
     esac
   done
 fi
@@ -12717,6 +12717,15 @@ fi
 
 if test "$with_libcurl" = yes ; then
 
+  # libcurl compiler/linker flags are kept separate from the global flags, so
+  # they have to be added back temporarily for the following tests.
+  pgac_save_CPPFLAGS=$CPPFLAGS
+  pgac_save_LDFLAGS=$LDFLAGS
+  pgac_save_LIBS=$LIBS
+
+  CPPFLAGS="$CPPFLAGS $LIBCURL_CPPFLAGS"
+  LDFLAGS="$LDFLAGS $LIBCURL_LDFLAGS"
+
   ac_fn_c_check_header_mongrel "$LINENO" "curl/curl.h" "ac_cv_header_curl_curl_h" "$ac_includes_default"
 if test "x$ac_cv_header_curl_curl_h" = xyes; then :
 
@@ -12725,6 +12734,9 @@ else
 fi
 
 
+
+  # LIBCURL_LDLIBS is determined here. Like the compiler flags, it should not
+  # pollute the global LIBS setting.
   { $as_echo "$as_me:${as_lineno-$LINENO}: checking for curl_multi_init in -lcurl" >&5
 $as_echo_n "checking for curl_multi_init in -lcurl... " >&6; }
 if ${ac_cv_lib_curl_curl_multi_init+:} false; then :
@@ -12774,12 +12786,6 @@ else
 fi
 
 
-  pgac_save_CPPFLAGS=$CPPFLAGS
-  pgac_save_LDFLAGS=$LDFLAGS
-  pgac_save_LIBS=$LIBS
-
-  CPPFLAGS="$LIBCURL_CPPFLAGS $CPPFLAGS"
-  LDFLAGS="$LIBCURL_LDFLAGS $LDFLAGS"
   LIBS="$LIBCURL_LDLIBS $LIBS"
 
   # Check to see whether the current platform supports threadsafe Curl
@@ -13309,6 +13315,23 @@ fi
 
 fi
 
+if test "$with_liburing" = yes; then
+  _LIBS="$LIBS"
+  LIBS="$LIBURING_LIBS $LIBS"
+  for ac_func in io_uring_queue_init_mem
+do :
+  ac_fn_c_check_func "$LINENO" "io_uring_queue_init_mem" "ac_cv_func_io_uring_queue_init_mem"
+if test "x$ac_cv_func_io_uring_queue_init_mem" = xyes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_IO_URING_QUEUE_INIT_MEM 1
+_ACEOF
+
+fi
+done
+
+  LIBS="$_LIBS"
+fi
+
 if test "$with_lz4" = yes ; then
   { $as_echo "$as_me:${as_lineno-$LINENO}: checking for LZ4_compress_default in -llz4" >&5
 $as_echo_n "checking for LZ4_compress_default in -llz4... " >&6; }
@@ -16635,7 +16658,7 @@ fi
 
 if test "$with_icu" = yes; then
   ac_save_CPPFLAGS=$CPPFLAGS
-  CPPFLAGS="$ICU_CFLAGS $CPPFLAGS"
+  CPPFLAGS="$CPPFLAGS $ICU_CFLAGS"
 
   # Verify we have ICU's header files
   ac_fn_c_check_header_mongrel "$LINENO" "unicode/ucol.h" "ac_cv_header_unicode_ucol_h" "$ac_includes_default"
@@ -17542,7 +17565,7 @@ $as_echo "#define HAVE_GCC__ATOMIC_INT64_CAS 1" >>confdefs.h
 fi
 
 
-# Check for x86 cpuid instruction
+# Check for __get_cpuid() and __cpuid()
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for __get_cpuid" >&5
 $as_echo_n "checking for __get_cpuid... " >&6; }
 if ${pgac_cv__get_cpuid+:} false; then :
@@ -17575,77 +17598,79 @@ if test x"$pgac_cv__get_cpuid" = x"yes"; then
 
 $as_echo "#define HAVE__GET_CPUID 1" >>confdefs.h
 
-fi
-
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for __get_cpuid_count" >&5
-$as_echo_n "checking for __get_cpuid_count... " >&6; }
-if ${pgac_cv__get_cpuid_count+:} false; then :
+else
+  # __cpuid()
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for __cpuid" >&5
+$as_echo_n "checking for __cpuid... " >&6; }
+if ${pgac_cv__cpuid+:} false; then :
   $as_echo_n "(cached) " >&6
 else
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
-#include <cpuid.h>
+#include <intrin.h>
 int
 main ()
 {
 unsigned int exx[4] = {0, 0, 0, 0};
-  __get_cpuid_count(7, 0, &exx[0], &exx[1], &exx[2], &exx[3]);
+    __cpuid(exx, 1);
 
   ;
   return 0;
 }
 _ACEOF
 if ac_fn_c_try_link "$LINENO"; then :
-  pgac_cv__get_cpuid_count="yes"
+  pgac_cv__cpuid="yes"
 else
-  pgac_cv__get_cpuid_count="no"
+  pgac_cv__cpuid="no"
 fi
 rm -f core conftest.err conftest.$ac_objext \
     conftest$ac_exeext conftest.$ac_ext
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $pgac_cv__get_cpuid_count" >&5
-$as_echo "$pgac_cv__get_cpuid_count" >&6; }
-if test x"$pgac_cv__get_cpuid_count" = x"yes"; then
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $pgac_cv__cpuid" >&5
+$as_echo "$pgac_cv__cpuid" >&6; }
+  if test x"$pgac_cv__cpuid" = x"yes"; then
 
-$as_echo "#define HAVE__GET_CPUID_COUNT 1" >>confdefs.h
+$as_echo "#define HAVE__CPUID 1" >>confdefs.h
 
+  fi
 fi
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for __cpuid" >&5
-$as_echo_n "checking for __cpuid... " >&6; }
-if ${pgac_cv__cpuid+:} false; then :
+# Check for __get_cpuid_count() and __cpuidex() in a similar fashion.
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for __get_cpuid_count" >&5
+$as_echo_n "checking for __get_cpuid_count... " >&6; }
+if ${pgac_cv__get_cpuid_count+:} false; then :
   $as_echo_n "(cached) " >&6
 else
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
-#include <intrin.h>
+#include <cpuid.h>
 int
 main ()
 {
 unsigned int exx[4] = {0, 0, 0, 0};
-  __get_cpuid(exx[0], 1);
+  __get_cpuid_count(7, 0, &exx[0], &exx[1], &exx[2], &exx[3]);
 
   ;
   return 0;
 }
 _ACEOF
 if ac_fn_c_try_link "$LINENO"; then :
-  pgac_cv__cpuid="yes"
+  pgac_cv__get_cpuid_count="yes"
 else
-  pgac_cv__cpuid="no"
+  pgac_cv__get_cpuid_count="no"
 fi
 rm -f core conftest.err conftest.$ac_objext \
     conftest$ac_exeext conftest.$ac_ext
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $pgac_cv__cpuid" >&5
-$as_echo "$pgac_cv__cpuid" >&6; }
-if test x"$pgac_cv__cpuid" = x"yes"; then
-
-$as_echo "#define HAVE__CPUID 1" >>confdefs.h
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $pgac_cv__get_cpuid_count" >&5
+$as_echo "$pgac_cv__get_cpuid_count" >&6; }
+if test x"$pgac_cv__get_cpuid_count" = x"yes"; then
 
-fi
+$as_echo "#define HAVE__GET_CPUID_COUNT 1" >>confdefs.h
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for __cpuidex" >&5
+else
+  # __cpuidex()
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for __cpuidex" >&5
 $as_echo_n "checking for __cpuidex... " >&6; }
 if ${pgac_cv__cpuidex+:} false; then :
   $as_echo_n "(cached) " >&6
@@ -17657,7 +17682,7 @@ int
 main ()
 {
 unsigned int exx[4] = {0, 0, 0, 0};
-  __get_cpuidex(exx[0], 7, 0);
+    __cpuidex(exx, 7, 0);
 
   ;
   return 0;
@@ -17673,10 +17698,11 @@ rm -f core conftest.err conftest.$ac_objext \
 fi
 { $as_echo "$as_me:${as_lineno-$LINENO}: result: $pgac_cv__cpuidex" >&5
 $as_echo "$pgac_cv__cpuidex" >&6; }
-if test x"$pgac_cv__cpuidex" = x"yes"; then
+  if test x"$pgac_cv__cpuidex" = x"yes"; then
 
 $as_echo "#define HAVE__CPUIDEX 1" >>confdefs.h
 
+  fi
 fi
 
 # Check for XSAVE intrinsics
@@ -18853,7 +18879,7 @@ Use --without-tcl to disable building PL/Tcl." "$LINENO" 5
     fi
     # now that we have TCL_INCLUDE_SPEC, we can check for <tcl.h>
     ac_save_CPPFLAGS=$CPPFLAGS
-    CPPFLAGS="$TCL_INCLUDE_SPEC $CPPFLAGS"
+    CPPFLAGS="$CPPFLAGS $TCL_INCLUDE_SPEC"
     ac_fn_c_check_header_mongrel "$LINENO" "tcl.h" "ac_cv_header_tcl_h" "$ac_includes_default"
 if test "x$ac_cv_header_tcl_h" = xyes; then :
 
@@ -18922,7 +18948,7 @@ fi
 # check for <Python.h>
 if test "$with_python" = yes; then
   ac_save_CPPFLAGS=$CPPFLAGS
-  CPPFLAGS="$python_includespec $CPPFLAGS"
+  CPPFLAGS="$CPPFLAGS $python_includespec"
   ac_fn_c_check_header_mongrel "$LINENO" "Python.h" "ac_cv_header_Python_h" "$ac_includes_default"
 if test "x$ac_cv_header_Python_h" = xyes; then :
 
diff --git a/configure.ac b/configure.ac
index b3efc49c97a9d..5f4548adc5cd1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1103,12 +1103,12 @@ if test "$with_libxml" = yes ; then
   # Note the user could also set XML2_CFLAGS/XML2_LIBS directly
   for pgac_option in $XML2_CFLAGS; do
     case $pgac_option in
-      -I*|-D*) CPPFLAGS="$CPPFLAGS $pgac_option";;
+      -I*|-D*) INCLUDES="$INCLUDES $pgac_option";;
     esac
   done
   for pgac_option in $XML2_LIBS; do
     case $pgac_option in
-      -L*) LDFLAGS="$LDFLAGS $pgac_option";;
+      -L*) LIBDIRS="$LIBDIRS $pgac_option";;
     esac
   done
 fi
@@ -1152,12 +1152,12 @@ if test "$with_lz4" = yes; then
   # note that -llz4 will be added by AC_CHECK_LIB below.
   for pgac_option in $LZ4_CFLAGS; do
     case $pgac_option in
-      -I*|-D*) CPPFLAGS="$CPPFLAGS $pgac_option";;
+      -I*|-D*) INCLUDES="$INCLUDES $pgac_option";;
     esac
   done
   for pgac_option in $LZ4_LIBS; do
     case $pgac_option in
-      -L*) LDFLAGS="$LDFLAGS $pgac_option";;
+      -L*) LIBDIRS="$LIBDIRS $pgac_option";;
     esac
   done
 fi
@@ -1177,12 +1177,12 @@ if test "$with_zstd" = yes; then
   # note that -lzstd will be added by AC_CHECK_LIB below.
   for pgac_option in $ZSTD_CFLAGS; do
     case $pgac_option in
-      -I*|-D*) CPPFLAGS="$CPPFLAGS $pgac_option";;
+      -I*|-D*) INCLUDES="$INCLUDES $pgac_option";;
     esac
   done
   for pgac_option in $ZSTD_LIBS; do
     case $pgac_option in
-      -L*) LDFLAGS="$LDFLAGS $pgac_option";;
+      -L*) LIBDIRS="$LIBDIRS $pgac_option";;
     esac
   done
 fi
@@ -1420,6 +1420,13 @@ if test "$with_libxslt" = yes ; then
   AC_CHECK_LIB(xslt, xsltCleanupGlobals, [], [AC_MSG_ERROR([library 'xslt' is required for XSLT support])])
 fi
 
+if test "$with_liburing" = yes; then
+  _LIBS="$LIBS"
+  LIBS="$LIBURING_LIBS $LIBS"
+  AC_CHECK_FUNCS([io_uring_queue_init_mem])
+  LIBS="$_LIBS"
+fi
+
 if test "$with_lz4" = yes ; then
   AC_CHECK_LIB(lz4, LZ4_compress_default, [], [AC_MSG_ERROR([library 'lz4' is required for LZ4 support])])
 fi
@@ -1937,7 +1944,7 @@ fi
 
 if test "$with_icu" = yes; then
   ac_save_CPPFLAGS=$CPPFLAGS
-  CPPFLAGS="$ICU_CFLAGS $CPPFLAGS"
+  CPPFLAGS="$CPPFLAGS $ICU_CFLAGS"
 
   # Verify we have ICU's header files
   AC_CHECK_HEADER(unicode/ucol.h, [],
@@ -2037,7 +2044,7 @@ PGAC_HAVE_GCC__ATOMIC_INT32_CAS
 PGAC_HAVE_GCC__ATOMIC_INT64_CAS
 
 
-# Check for x86 cpuid instruction
+# Check for __get_cpuid() and __cpuid()
 AC_CACHE_CHECK([for __get_cpuid], [pgac_cv__get_cpuid],
 [AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <cpuid.h>],
   [[unsigned int exx[4] = {0, 0, 0, 0};
@@ -2047,8 +2054,21 @@ AC_CACHE_CHECK([for __get_cpuid], [pgac_cv__get_cpuid],
   [pgac_cv__get_cpuid="no"])])
 if test x"$pgac_cv__get_cpuid" = x"yes"; then
   AC_DEFINE(HAVE__GET_CPUID, 1, [Define to 1 if you have __get_cpuid.])
+else
+  # __cpuid()
+  AC_CACHE_CHECK([for __cpuid], [pgac_cv__cpuid],
+  [AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <intrin.h>],
+    [[unsigned int exx[4] = {0, 0, 0, 0};
+    __cpuid(exx, 1);
+    ]])],
+    [pgac_cv__cpuid="yes"],
+    [pgac_cv__cpuid="no"])])
+  if test x"$pgac_cv__cpuid" = x"yes"; then
+    AC_DEFINE(HAVE__CPUID, 1, [Define to 1 if you have __cpuid.])
+  fi
 fi
 
+# Check for __get_cpuid_count() and __cpuidex() in a similar fashion.
 AC_CACHE_CHECK([for __get_cpuid_count], [pgac_cv__get_cpuid_count],
 [AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <cpuid.h>],
   [[unsigned int exx[4] = {0, 0, 0, 0};
@@ -2058,28 +2078,18 @@ AC_CACHE_CHECK([for __get_cpuid_count], [pgac_cv__get_cpuid_count],
   [pgac_cv__get_cpuid_count="no"])])
 if test x"$pgac_cv__get_cpuid_count" = x"yes"; then
   AC_DEFINE(HAVE__GET_CPUID_COUNT, 1, [Define to 1 if you have __get_cpuid_count.])
-fi
-
-AC_CACHE_CHECK([for __cpuid], [pgac_cv__cpuid],
-[AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <intrin.h>],
-  [[unsigned int exx[4] = {0, 0, 0, 0};
-  __get_cpuid(exx[0], 1);
-  ]])],
-  [pgac_cv__cpuid="yes"],
-  [pgac_cv__cpuid="no"])])
-if test x"$pgac_cv__cpuid" = x"yes"; then
-  AC_DEFINE(HAVE__CPUID, 1, [Define to 1 if you have __cpuid.])
-fi
-
-AC_CACHE_CHECK([for __cpuidex], [pgac_cv__cpuidex],
-[AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <intrin.h>],
-  [[unsigned int exx[4] = {0, 0, 0, 0};
-  __get_cpuidex(exx[0], 7, 0);
-  ]])],
-  [pgac_cv__cpuidex="yes"],
-  [pgac_cv__cpuidex="no"])])
-if test x"$pgac_cv__cpuidex" = x"yes"; then
-  AC_DEFINE(HAVE__CPUIDEX, 1, [Define to 1 if you have __cpuidex.])
+else
+  # __cpuidex()
+  AC_CACHE_CHECK([for __cpuidex], [pgac_cv__cpuidex],
+  [AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <intrin.h>],
+    [[unsigned int exx[4] = {0, 0, 0, 0};
+    __cpuidex(exx, 7, 0);
+    ]])],
+    [pgac_cv__cpuidex="yes"],
+    [pgac_cv__cpuidex="no"])])
+  if test x"$pgac_cv__cpuidex" = x"yes"; then
+    AC_DEFINE(HAVE__CPUIDEX, 1, [Define to 1 if you have __cpuidex.])
+  fi
 fi
 
 # Check for XSAVE intrinsics
@@ -2337,7 +2347,7 @@ Use --without-tcl to disable building PL/Tcl.])
     fi
     # now that we have TCL_INCLUDE_SPEC, we can check for <tcl.h>
     ac_save_CPPFLAGS=$CPPFLAGS
-    CPPFLAGS="$TCL_INCLUDE_SPEC $CPPFLAGS"
+    CPPFLAGS="$CPPFLAGS $TCL_INCLUDE_SPEC"
     AC_CHECK_HEADER(tcl.h, [], [AC_MSG_ERROR([header file <tcl.h> is required for Tcl])])
     CPPFLAGS=$ac_save_CPPFLAGS
 fi
@@ -2374,7 +2384,7 @@ fi
 # check for <Python.h>
 if test "$with_python" = yes; then
   ac_save_CPPFLAGS=$CPPFLAGS
-  CPPFLAGS="$python_includespec $CPPFLAGS"
+  CPPFLAGS="$CPPFLAGS $python_includespec"
   AC_CHECK_HEADER(Python.h, [], [AC_MSG_ERROR([header file <Python.h> is required for Python])])
   CPPFLAGS=$ac_save_CPPFLAGS
 fi
diff --git a/contrib/amcheck/expected/check_btree.out b/contrib/amcheck/expected/check_btree.out
index c6f4b16c55615..6558f2c5a4ff4 100644
--- a/contrib/amcheck/expected/check_btree.out
+++ b/contrib/amcheck/expected/check_btree.out
@@ -60,6 +60,14 @@ SELECT bt_index_parent_check('bttest_a_brin_idx');
 ERROR:  expected "btree" index as targets for verification
 DETAIL:  Relation "bttest_a_brin_idx" is a brin index.
 ROLLBACK;
+-- verify partitioned indexes are rejected (error)
+BEGIN;
+CREATE TABLE bttest_partitioned (a int, b int) PARTITION BY list (a);
+CREATE INDEX bttest_btree_partitioned_idx ON bttest_partitioned USING btree (b);
+SELECT bt_index_parent_check('bttest_btree_partitioned_idx');
+ERROR:  expected index as targets for verification
+DETAIL:  This operation is not supported for partitioned indexes.
+ROLLBACK;
 -- normal check outside of xact
 SELECT bt_index_check('bttest_a_idx');
  bt_index_check 
diff --git a/contrib/amcheck/sql/check_btree.sql b/contrib/amcheck/sql/check_btree.sql
index 0793dbfeebd82..171f7f691ec60 100644
--- a/contrib/amcheck/sql/check_btree.sql
+++ b/contrib/amcheck/sql/check_btree.sql
@@ -52,6 +52,13 @@ CREATE INDEX bttest_a_brin_idx ON bttest_a USING brin(id);
 SELECT bt_index_parent_check('bttest_a_brin_idx');
 ROLLBACK;
 
+-- verify partitioned indexes are rejected (error)
+BEGIN;
+CREATE TABLE bttest_partitioned (a int, b int) PARTITION BY list (a);
+CREATE INDEX bttest_btree_partitioned_idx ON bttest_partitioned USING btree (b);
+SELECT bt_index_parent_check('bttest_btree_partitioned_idx');
+ROLLBACK;
+
 -- normal check outside of xact
 SELECT bt_index_check('bttest_a_idx');
 -- more expansive tests
diff --git a/contrib/amcheck/verify_common.c b/contrib/amcheck/verify_common.c
index d095e62ce551f..a31ce06ed99a3 100644
--- a/contrib/amcheck/verify_common.c
+++ b/contrib/amcheck/verify_common.c
@@ -18,11 +18,13 @@
 #include "verify_common.h"
 #include "catalog/index.h"
 #include "catalog/pg_am.h"
+#include "commands/defrem.h"
 #include "commands/tablecmds.h"
 #include "utils/guc.h"
 #include "utils/syscache.h"
 
 static bool amcheck_index_mainfork_expected(Relation rel);
+static bool index_checkable(Relation rel, Oid am_id);
 
 
 /*
@@ -155,23 +157,21 @@ amcheck_lock_relation_and_check(Oid indrelid,
  * callable by non-superusers. If granted, it's useful to be able to check a
  * whole cluster.
  */
-bool
+static bool
 index_checkable(Relation rel, Oid am_id)
 {
-	if (rel->rd_rel->relkind != RELKIND_INDEX ||
-		rel->rd_rel->relam != am_id)
-	{
-		HeapTuple	amtup;
-		HeapTuple	amtuprel;
+	if (rel->rd_rel->relkind != RELKIND_INDEX)
+		ereport(ERROR,
+				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+				 errmsg("expected index as targets for verification"),
+				 errdetail_relkind_not_supported(rel->rd_rel->relkind)));
 
-		amtup = SearchSysCache1(AMOID, ObjectIdGetDatum(am_id));
-		amtuprel = SearchSysCache1(AMOID, ObjectIdGetDatum(rel->rd_rel->relam));
+	if (rel->rd_rel->relam != am_id)
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-				 errmsg("expected \"%s\" index as targets for verification", NameStr(((Form_pg_am) GETSTRUCT(amtup))->amname)),
+				 errmsg("expected \"%s\" index as targets for verification", get_am_name(am_id)),
 				 errdetail("Relation \"%s\" is a %s index.",
-						   RelationGetRelationName(rel), NameStr(((Form_pg_am) GETSTRUCT(amtuprel))->amname))));
-	}
+						   RelationGetRelationName(rel), get_am_name(rel->rd_rel->relam))));
 
 	if (RELATION_IS_OTHER_TEMP(rel))
 		ereport(ERROR,
@@ -182,7 +182,7 @@ index_checkable(Relation rel, Oid am_id)
 
 	if (!rel->rd_index->indisvalid)
 		ereport(ERROR,
-				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
 				 errmsg("cannot check index \"%s\"",
 						RelationGetRelationName(rel)),
 				 errdetail("Index is not valid.")));
diff --git a/contrib/amcheck/verify_common.h b/contrib/amcheck/verify_common.h
index e78adb68808f0..3f4c57f963d6b 100644
--- a/contrib/amcheck/verify_common.h
+++ b/contrib/amcheck/verify_common.h
@@ -16,8 +16,7 @@
 #include "utils/relcache.h"
 #include "miscadmin.h"
 
-/* Typedefs for callback functions for amcheck_lock_relation_and_check */
-typedef void (*IndexCheckableCallback) (Relation index);
+/* Typedef for callback function for amcheck_lock_relation_and_check */
 typedef void (*IndexDoCheckCallback) (Relation rel,
 									  Relation heaprel,
 									  void *state,
@@ -27,5 +26,3 @@ extern void amcheck_lock_relation_and_check(Oid indrelid,
 											Oid am_id,
 											IndexDoCheckCallback check,
 											LOCKMODE lockmode, void *state);
-
-extern bool index_checkable(Relation rel, Oid am_id);
diff --git a/contrib/amcheck/verify_heapam.c b/contrib/amcheck/verify_heapam.c
index aa9cccd1da4fe..4963e9245cb54 100644
--- a/contrib/amcheck/verify_heapam.c
+++ b/contrib/amcheck/verify_heapam.c
@@ -1942,7 +1942,7 @@ check_tuple(HeapCheckContext *ctx, bool *xmin_commit_status_ok,
 	if (RelationGetDescr(ctx->rel)->natts < ctx->natts)
 	{
 		report_corruption(ctx,
-						  psprintf("number of attributes %u exceeds maximum expected for table %u",
+						  psprintf("number of attributes %u exceeds maximum %u expected for table",
 								   ctx->natts,
 								   RelationGetDescr(ctx->rel)->natts));
 		return;
diff --git a/contrib/amcheck/verify_nbtree.c b/contrib/amcheck/verify_nbtree.c
index f11c43a0ed797..0949c88983ac2 100644
--- a/contrib/amcheck/verify_nbtree.c
+++ b/contrib/amcheck/verify_nbtree.c
@@ -913,7 +913,7 @@ bt_report_duplicate(BtreeCheckState *state,
 			(errcode(ERRCODE_INDEX_CORRUPTED),
 			 errmsg("index uniqueness is violated for index \"%s\"",
 					RelationGetRelationName(state->rel)),
-			 errdetail("Index %s%s and%s%s (point to heap %s and %s) page lsn=%X/%X.",
+			 errdetail("Index %s%s and%s%s (point to heap %s and %s) page lsn=%X/%08X.",
 					   itid, pposting, nitid, pnposting, htid, nhtid,
 					   LSN_FORMAT_ARGS(state->targetlsn))));
 }
@@ -1058,7 +1058,7 @@ bt_leftmost_ignoring_half_dead(BtreeCheckState *state,
 					(errcode(ERRCODE_NO_DATA),
 					 errmsg_internal("harmless interrupted page deletion detected in index \"%s\"",
 									 RelationGetRelationName(state->rel)),
-					 errdetail_internal("Block=%u right block=%u page lsn=%X/%X.",
+					 errdetail_internal("Block=%u right block=%u page lsn=%X/%08X.",
 										reached, reached_from,
 										LSN_FORMAT_ARGS(pagelsn))));
 
@@ -1283,7 +1283,7 @@ bt_target_page_check(BtreeCheckState *state)
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("wrong number of high key index tuple attributes in index \"%s\"",
 							RelationGetRelationName(state->rel)),
-					 errdetail_internal("Index block=%u natts=%u block type=%s page lsn=%X/%X.",
+					 errdetail_internal("Index block=%u natts=%u block type=%s page lsn=%X/%08X.",
 										state->targetblock,
 										BTreeTupleGetNAtts(itup, state->rel),
 										P_ISLEAF(topaque) ? "heap" : "index",
@@ -1332,7 +1332,7 @@ bt_target_page_check(BtreeCheckState *state)
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("index tuple size does not equal lp_len in index \"%s\"",
 							RelationGetRelationName(state->rel)),
-					 errdetail_internal("Index tid=(%u,%u) tuple size=%zu lp_len=%u page lsn=%X/%X.",
+					 errdetail_internal("Index tid=(%u,%u) tuple size=%zu lp_len=%u page lsn=%X/%08X.",
 										state->targetblock, offset,
 										tupsize, ItemIdGetLength(itemid),
 										LSN_FORMAT_ARGS(state->targetlsn)),
@@ -1356,7 +1356,7 @@ bt_target_page_check(BtreeCheckState *state)
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("wrong number of index tuple attributes in index \"%s\"",
 							RelationGetRelationName(state->rel)),
-					 errdetail_internal("Index tid=%s natts=%u points to %s tid=%s page lsn=%X/%X.",
+					 errdetail_internal("Index tid=%s natts=%u points to %s tid=%s page lsn=%X/%08X.",
 										itid,
 										BTreeTupleGetNAtts(itup, state->rel),
 										P_ISLEAF(topaque) ? "heap" : "index",
@@ -1406,7 +1406,7 @@ bt_target_page_check(BtreeCheckState *state)
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("could not find tuple using search from root page in index \"%s\"",
 							RelationGetRelationName(state->rel)),
-					 errdetail_internal("Index tid=%s points to heap tid=%s page lsn=%X/%X.",
+					 errdetail_internal("Index tid=%s points to heap tid=%s page lsn=%X/%08X.",
 										itid, htid,
 										LSN_FORMAT_ARGS(state->targetlsn))));
 		}
@@ -1435,7 +1435,7 @@ bt_target_page_check(BtreeCheckState *state)
 							(errcode(ERRCODE_INDEX_CORRUPTED),
 							 errmsg_internal("posting list contains misplaced TID in index \"%s\"",
 											 RelationGetRelationName(state->rel)),
-							 errdetail_internal("Index tid=%s posting list offset=%d page lsn=%X/%X.",
+							 errdetail_internal("Index tid=%s posting list offset=%d page lsn=%X/%08X.",
 												itid, i,
 												LSN_FORMAT_ARGS(state->targetlsn))));
 				}
@@ -1488,7 +1488,7 @@ bt_target_page_check(BtreeCheckState *state)
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("index row size %zu exceeds maximum for index \"%s\"",
 							tupsize, RelationGetRelationName(state->rel)),
-					 errdetail_internal("Index tid=%s points to %s tid=%s page lsn=%X/%X.",
+					 errdetail_internal("Index tid=%s points to %s tid=%s page lsn=%X/%08X.",
 										itid,
 										P_ISLEAF(topaque) ? "heap" : "index",
 										htid,
@@ -1595,7 +1595,7 @@ bt_target_page_check(BtreeCheckState *state)
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("high key invariant violated for index \"%s\"",
 							RelationGetRelationName(state->rel)),
-					 errdetail_internal("Index tid=%s points to %s tid=%s page lsn=%X/%X.",
+					 errdetail_internal("Index tid=%s points to %s tid=%s page lsn=%X/%08X.",
 										itid,
 										P_ISLEAF(topaque) ? "heap" : "index",
 										htid,
@@ -1641,9 +1641,7 @@ bt_target_page_check(BtreeCheckState *state)
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("item order invariant violated for index \"%s\"",
 							RelationGetRelationName(state->rel)),
-					 errdetail_internal("Lower index tid=%s (points to %s tid=%s) "
-										"higher index tid=%s (points to %s tid=%s) "
-										"page lsn=%X/%X.",
+					 errdetail_internal("Lower index tid=%s (points to %s tid=%s) higher index tid=%s (points to %s tid=%s) page lsn=%X/%08X.",
 										itid,
 										P_ISLEAF(topaque) ? "heap" : "index",
 										htid,
@@ -1760,7 +1758,7 @@ bt_target_page_check(BtreeCheckState *state)
 						(errcode(ERRCODE_INDEX_CORRUPTED),
 						 errmsg("cross page item order invariant violated for index \"%s\"",
 								RelationGetRelationName(state->rel)),
-						 errdetail_internal("Last item on page tid=(%u,%u) page lsn=%X/%X.",
+						 errdetail_internal("Last item on page tid=(%u,%u) page lsn=%X/%08X.",
 											state->targetblock, offset,
 											LSN_FORMAT_ARGS(state->targetlsn))));
 			}
@@ -1813,7 +1811,7 @@ bt_target_page_check(BtreeCheckState *state)
 								(errcode(ERRCODE_INDEX_CORRUPTED),
 								 errmsg("right block of leaf block is non-leaf for index \"%s\"",
 										RelationGetRelationName(state->rel)),
-								 errdetail_internal("Block=%u page lsn=%X/%X.",
+								 errdetail_internal("Block=%u page lsn=%X/%08X.",
 													state->targetblock,
 													LSN_FORMAT_ARGS(state->targetlsn))));
 
@@ -2237,7 +2235,7 @@ bt_child_highkey_check(BtreeCheckState *state,
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("the first child of leftmost target page is not leftmost of its level in index \"%s\"",
 							RelationGetRelationName(state->rel)),
-					 errdetail_internal("Target block=%u child block=%u target page lsn=%X/%X.",
+					 errdetail_internal("Target block=%u child block=%u target page lsn=%X/%08X.",
 										state->targetblock, blkno,
 										LSN_FORMAT_ARGS(state->targetlsn))));
 
@@ -2323,7 +2321,7 @@ bt_child_highkey_check(BtreeCheckState *state,
 								(errcode(ERRCODE_INDEX_CORRUPTED),
 								 errmsg("child high key is greater than rightmost pivot key on target level in index \"%s\"",
 										RelationGetRelationName(state->rel)),
-								 errdetail_internal("Target block=%u child block=%u target page lsn=%X/%X.",
+								 errdetail_internal("Target block=%u child block=%u target page lsn=%X/%08X.",
 													state->targetblock, blkno,
 													LSN_FORMAT_ARGS(state->targetlsn))));
 					pivotkey_offset = P_HIKEY;
@@ -2353,7 +2351,7 @@ bt_child_highkey_check(BtreeCheckState *state,
 							(errcode(ERRCODE_INDEX_CORRUPTED),
 							 errmsg("can't find left sibling high key in index \"%s\"",
 									RelationGetRelationName(state->rel)),
-							 errdetail_internal("Target block=%u child block=%u target page lsn=%X/%X.",
+							 errdetail_internal("Target block=%u child block=%u target page lsn=%X/%08X.",
 												state->targetblock, blkno,
 												LSN_FORMAT_ARGS(state->targetlsn))));
 				itup = state->lowkey;
@@ -2365,7 +2363,7 @@ bt_child_highkey_check(BtreeCheckState *state,
 						(errcode(ERRCODE_INDEX_CORRUPTED),
 						 errmsg("mismatch between parent key and child high key in index \"%s\"",
 								RelationGetRelationName(state->rel)),
-						 errdetail_internal("Target block=%u child block=%u target page lsn=%X/%X.",
+						 errdetail_internal("Target block=%u child block=%u target page lsn=%X/%08X.",
 											state->targetblock, blkno,
 											LSN_FORMAT_ARGS(state->targetlsn))));
 			}
@@ -2505,7 +2503,7 @@ bt_child_check(BtreeCheckState *state, BTScanInsert targetkey,
 				(errcode(ERRCODE_INDEX_CORRUPTED),
 				 errmsg("downlink to deleted page found in index \"%s\"",
 						RelationGetRelationName(state->rel)),
-				 errdetail_internal("Parent block=%u child block=%u parent page lsn=%X/%X.",
+				 errdetail_internal("Parent block=%u child block=%u parent page lsn=%X/%08X.",
 									state->targetblock, childblock,
 									LSN_FORMAT_ARGS(state->targetlsn))));
 
@@ -2546,7 +2544,7 @@ bt_child_check(BtreeCheckState *state, BTScanInsert targetkey,
 					(errcode(ERRCODE_INDEX_CORRUPTED),
 					 errmsg("down-link lower bound invariant violated for index \"%s\"",
 							RelationGetRelationName(state->rel)),
-					 errdetail_internal("Parent block=%u child index tid=(%u,%u) parent page lsn=%X/%X.",
+					 errdetail_internal("Parent block=%u child index tid=(%u,%u) parent page lsn=%X/%08X.",
 										state->targetblock, childblock, offset,
 										LSN_FORMAT_ARGS(state->targetlsn))));
 	}
@@ -2616,7 +2614,7 @@ bt_downlink_missing_check(BtreeCheckState *state, bool rightsplit,
 				(errcode(ERRCODE_NO_DATA),
 				 errmsg_internal("harmless interrupted page split detected in index \"%s\"",
 								 RelationGetRelationName(state->rel)),
-				 errdetail_internal("Block=%u level=%u left sibling=%u page lsn=%X/%X.",
+				 errdetail_internal("Block=%u level=%u left sibling=%u page lsn=%X/%08X.",
 									blkno, opaque->btpo_level,
 									opaque->btpo_prev,
 									LSN_FORMAT_ARGS(pagelsn))));
@@ -2638,7 +2636,7 @@ bt_downlink_missing_check(BtreeCheckState *state, bool rightsplit,
 				(errcode(ERRCODE_INDEX_CORRUPTED),
 				 errmsg("leaf index block lacks downlink in index \"%s\"",
 						RelationGetRelationName(state->rel)),
-				 errdetail_internal("Block=%u page lsn=%X/%X.",
+				 errdetail_internal("Block=%u page lsn=%X/%08X.",
 									blkno,
 									LSN_FORMAT_ARGS(pagelsn))));
 
@@ -2704,7 +2702,7 @@ bt_downlink_missing_check(BtreeCheckState *state, bool rightsplit,
 				(errcode(ERRCODE_INDEX_CORRUPTED),
 				 errmsg_internal("downlink to deleted leaf page found in index \"%s\"",
 								 RelationGetRelationName(state->rel)),
-				 errdetail_internal("Top parent/target block=%u leaf block=%u top parent/under check lsn=%X/%X.",
+				 errdetail_internal("Top parent/target block=%u leaf block=%u top parent/under check lsn=%X/%08X.",
 									blkno, childblk,
 									LSN_FORMAT_ARGS(pagelsn))));
 
@@ -2730,7 +2728,7 @@ bt_downlink_missing_check(BtreeCheckState *state, bool rightsplit,
 			(errcode(ERRCODE_INDEX_CORRUPTED),
 			 errmsg("internal index block lacks downlink in index \"%s\"",
 					RelationGetRelationName(state->rel)),
-			 errdetail_internal("Block=%u level=%u page lsn=%X/%X.",
+			 errdetail_internal("Block=%u level=%u page lsn=%X/%08X.",
 								blkno, opaque->btpo_level,
 								LSN_FORMAT_ARGS(pagelsn))));
 }
diff --git a/contrib/auto_explain/Makefile b/contrib/auto_explain/Makefile
index efd127d3cae64..94ab28e7c06b9 100644
--- a/contrib/auto_explain/Makefile
+++ b/contrib/auto_explain/Makefile
@@ -6,6 +6,8 @@ OBJS = \
 	auto_explain.o
 PGFILEDESC = "auto_explain - logging facility for execution plans"
 
+REGRESS = alter_reset
+
 TAP_TESTS = 1
 
 ifdef USE_PGXS
diff --git a/contrib/auto_explain/expected/alter_reset.out b/contrib/auto_explain/expected/alter_reset.out
new file mode 100644
index 0000000000000..ec355189806ae
--- /dev/null
+++ b/contrib/auto_explain/expected/alter_reset.out
@@ -0,0 +1,19 @@
+--
+-- This tests resetting unknown custom GUCs with reserved prefixes.  There's
+-- nothing specific to auto_explain; this is just a convenient place to put
+-- this test.
+--
+SELECT current_database() AS datname \gset
+CREATE ROLE regress_ae_role;
+ALTER DATABASE :"datname" SET auto_explain.bogus = 1;
+ALTER ROLE regress_ae_role SET auto_explain.bogus = 1;
+ALTER ROLE regress_ae_role IN DATABASE :"datname" SET auto_explain.bogus = 1;
+ALTER SYSTEM SET auto_explain.bogus = 1;
+LOAD 'auto_explain';
+WARNING:  invalid configuration parameter name "auto_explain.bogus", removing it
+DETAIL:  "auto_explain" is now a reserved prefix.
+ALTER DATABASE :"datname" RESET auto_explain.bogus;
+ALTER ROLE regress_ae_role RESET auto_explain.bogus;
+ALTER ROLE regress_ae_role IN DATABASE :"datname" RESET auto_explain.bogus;
+ALTER SYSTEM RESET auto_explain.bogus;
+DROP ROLE regress_ae_role;
diff --git a/contrib/auto_explain/meson.build b/contrib/auto_explain/meson.build
index 92dc9df6f7cac..a9b45cc235f12 100644
--- a/contrib/auto_explain/meson.build
+++ b/contrib/auto_explain/meson.build
@@ -20,6 +20,11 @@ tests += {
   'name': 'auto_explain',
   'sd': meson.current_source_dir(),
   'bd': meson.current_build_dir(),
+  'regress': {
+    'sql': [
+      'alter_reset',
+    ],
+  },
   'tap': {
     'tests': [
       't/001_auto_explain.pl',
diff --git a/contrib/auto_explain/sql/alter_reset.sql b/contrib/auto_explain/sql/alter_reset.sql
new file mode 100644
index 0000000000000..bf621454ec24a
--- /dev/null
+++ b/contrib/auto_explain/sql/alter_reset.sql
@@ -0,0 +1,22 @@
+--
+-- This tests resetting unknown custom GUCs with reserved prefixes.  There's
+-- nothing specific to auto_explain; this is just a convenient place to put
+-- this test.
+--
+
+SELECT current_database() AS datname \gset
+CREATE ROLE regress_ae_role;
+
+ALTER DATABASE :"datname" SET auto_explain.bogus = 1;
+ALTER ROLE regress_ae_role SET auto_explain.bogus = 1;
+ALTER ROLE regress_ae_role IN DATABASE :"datname" SET auto_explain.bogus = 1;
+ALTER SYSTEM SET auto_explain.bogus = 1;
+
+LOAD 'auto_explain';
+
+ALTER DATABASE :"datname" RESET auto_explain.bogus;
+ALTER ROLE regress_ae_role RESET auto_explain.bogus;
+ALTER ROLE regress_ae_role IN DATABASE :"datname" RESET auto_explain.bogus;
+ALTER SYSTEM RESET auto_explain.bogus;
+
+DROP ROLE regress_ae_role;
diff --git a/contrib/basebackup_to_shell/meson.build b/contrib/basebackup_to_shell/meson.build
index 8c88242456e80..8a4f170c5f829 100644
--- a/contrib/basebackup_to_shell/meson.build
+++ b/contrib/basebackup_to_shell/meson.build
@@ -24,7 +24,7 @@ tests += {
     'tests': [
       't/001_basic.pl',
     ],
-    'env': {'GZIP_PROGRAM': gzip.found() ? gzip.path() : '',
-            'TAR': tar.found() ? tar.path() : '' },
+    'env': {'GZIP_PROGRAM': gzip.found() ? gzip.full_path() : '',
+            'TAR': tar.found() ? tar.full_path() : '' },
   },
 }
diff --git a/contrib/basic_archive/basic_archive.c b/contrib/basic_archive/basic_archive.c
index 4a8b8c7ac29c1..8fc633d2cbf62 100644
--- a/contrib/basic_archive/basic_archive.c
+++ b/contrib/basic_archive/basic_archive.c
@@ -65,7 +65,7 @@ void
 _PG_init(void)
 {
 	DefineCustomStringVariable("basic_archive.archive_directory",
-							   gettext_noop("Archive file destination directory."),
+							   "Archive file destination directory.",
 							   NULL,
 							   &archive_directory,
 							   "",
diff --git a/contrib/btree_gin/Makefile b/contrib/btree_gin/Makefile
index 0a15811516819..ad054598db6c9 100644
--- a/contrib/btree_gin/Makefile
+++ b/contrib/btree_gin/Makefile
@@ -7,7 +7,7 @@ OBJS = \
 
 EXTENSION = btree_gin
 DATA = btree_gin--1.0.sql btree_gin--1.0--1.1.sql btree_gin--1.1--1.2.sql \
-	 btree_gin--1.2--1.3.sql
+	 btree_gin--1.2--1.3.sql btree_gin--1.3--1.4.sql
 PGFILEDESC = "btree_gin - B-tree equivalent GIN operator classes"
 
 REGRESS = install_btree_gin int2 int4 int8 float4 float8 money oid \
diff --git a/contrib/btree_gin/btree_gin--1.3--1.4.sql b/contrib/btree_gin/btree_gin--1.3--1.4.sql
new file mode 100644
index 0000000000000..61b5dcbede6c5
--- /dev/null
+++ b/contrib/btree_gin/btree_gin--1.3--1.4.sql
@@ -0,0 +1,151 @@
+/* contrib/btree_gin/btree_gin--1.3--1.4.sql */
+
+-- complain if script is sourced in psql, rather than via CREATE EXTENSION
+\echo Use "ALTER EXTENSION btree_gin UPDATE TO '1.4'" to load this file. \quit
+
+--
+-- Cross-type operator support is new in 1.4.  We only need to worry
+-- about this for cross-type operators that exist in core.
+--
+-- Because the opclass extractQuery and consistent methods don't directly
+-- get any information about the datatype of the RHS value, we have to
+-- encode that in the operator strategy numbers.  The strategy numbers
+-- are the operator's normal btree strategy (1-5) plus 16 times a code
+-- for the RHS datatype.
+--
+
+ALTER OPERATOR FAMILY int2_ops USING gin
+ADD
+    -- Code 1: RHS is int4
+    OPERATOR        0x11    < (int2, int4),
+    OPERATOR        0x12    <= (int2, int4),
+    OPERATOR        0x13    = (int2, int4),
+    OPERATOR        0x14    >= (int2, int4),
+    OPERATOR        0x15    > (int2, int4),
+    -- Code 2: RHS is int8
+    OPERATOR        0x21    < (int2, int8),
+    OPERATOR        0x22    <= (int2, int8),
+    OPERATOR        0x23    = (int2, int8),
+    OPERATOR        0x24    >= (int2, int8),
+    OPERATOR        0x25    > (int2, int8)
+;
+
+ALTER OPERATOR FAMILY int4_ops USING gin
+ADD
+    -- Code 1: RHS is int2
+    OPERATOR        0x11    < (int4, int2),
+    OPERATOR        0x12    <= (int4, int2),
+    OPERATOR        0x13    = (int4, int2),
+    OPERATOR        0x14    >= (int4, int2),
+    OPERATOR        0x15    > (int4, int2),
+    -- Code 2: RHS is int8
+    OPERATOR        0x21    < (int4, int8),
+    OPERATOR        0x22    <= (int4, int8),
+    OPERATOR        0x23    = (int4, int8),
+    OPERATOR        0x24    >= (int4, int8),
+    OPERATOR        0x25    > (int4, int8)
+;
+
+ALTER OPERATOR FAMILY int8_ops USING gin
+ADD
+    -- Code 1: RHS is int2
+    OPERATOR        0x11    < (int8, int2),
+    OPERATOR        0x12    <= (int8, int2),
+    OPERATOR        0x13    = (int8, int2),
+    OPERATOR        0x14    >= (int8, int2),
+    OPERATOR        0x15    > (int8, int2),
+    -- Code 2: RHS is int4
+    OPERATOR        0x21    < (int8, int4),
+    OPERATOR        0x22    <= (int8, int4),
+    OPERATOR        0x23    = (int8, int4),
+    OPERATOR        0x24    >= (int8, int4),
+    OPERATOR        0x25    > (int8, int4)
+;
+
+ALTER OPERATOR FAMILY float4_ops USING gin
+ADD
+    -- Code 1: RHS is float8
+    OPERATOR        0x11    < (float4, float8),
+    OPERATOR        0x12    <= (float4, float8),
+    OPERATOR        0x13    = (float4, float8),
+    OPERATOR        0x14    >= (float4, float8),
+    OPERATOR        0x15    > (float4, float8)
+;
+
+ALTER OPERATOR FAMILY float8_ops USING gin
+ADD
+    -- Code 1: RHS is float4
+    OPERATOR        0x11    < (float8, float4),
+    OPERATOR        0x12    <= (float8, float4),
+    OPERATOR        0x13    = (float8, float4),
+    OPERATOR        0x14    >= (float8, float4),
+    OPERATOR        0x15    > (float8, float4)
+;
+
+ALTER OPERATOR FAMILY text_ops USING gin
+ADD
+    -- Code 1: RHS is name
+    OPERATOR        0x11    < (text, name),
+    OPERATOR        0x12    <= (text, name),
+    OPERATOR        0x13    = (text, name),
+    OPERATOR        0x14    >= (text, name),
+    OPERATOR        0x15    > (text, name)
+;
+
+ALTER OPERATOR FAMILY name_ops USING gin
+ADD
+    -- Code 1: RHS is text
+    OPERATOR        0x11    < (name, text),
+    OPERATOR        0x12    <= (name, text),
+    OPERATOR        0x13    = (name, text),
+    OPERATOR        0x14    >= (name, text),
+    OPERATOR        0x15    > (name, text)
+;
+
+ALTER OPERATOR FAMILY date_ops USING gin
+ADD
+    -- Code 1: RHS is timestamp
+    OPERATOR        0x11    < (date, timestamp),
+    OPERATOR        0x12    <= (date, timestamp),
+    OPERATOR        0x13    = (date, timestamp),
+    OPERATOR        0x14    >= (date, timestamp),
+    OPERATOR        0x15    > (date, timestamp),
+    -- Code 2: RHS is timestamptz
+    OPERATOR        0x21    < (date, timestamptz),
+    OPERATOR        0x22    <= (date, timestamptz),
+    OPERATOR        0x23    = (date, timestamptz),
+    OPERATOR        0x24    >= (date, timestamptz),
+    OPERATOR        0x25    > (date, timestamptz)
+;
+
+ALTER OPERATOR FAMILY timestamp_ops USING gin
+ADD
+    -- Code 1: RHS is date
+    OPERATOR        0x11    < (timestamp, date),
+    OPERATOR        0x12    <= (timestamp, date),
+    OPERATOR        0x13    = (timestamp, date),
+    OPERATOR        0x14    >= (timestamp, date),
+    OPERATOR        0x15    > (timestamp, date),
+    -- Code 2: RHS is timestamptz
+    OPERATOR        0x21    < (timestamp, timestamptz),
+    OPERATOR        0x22    <= (timestamp, timestamptz),
+    OPERATOR        0x23    = (timestamp, timestamptz),
+    OPERATOR        0x24    >= (timestamp, timestamptz),
+    OPERATOR        0x25    > (timestamp, timestamptz)
+;
+
+ALTER OPERATOR FAMILY timestamptz_ops USING gin
+ADD
+    -- Code 1: RHS is date
+    OPERATOR        0x11    < (timestamptz, date),
+    OPERATOR        0x12    <= (timestamptz, date),
+    OPERATOR        0x13    = (timestamptz, date),
+    OPERATOR        0x14    >= (timestamptz, date),
+    OPERATOR        0x15    > (timestamptz, date),
+    -- Code 2: RHS is timestamp
+    OPERATOR        0x21    < (timestamptz, timestamp),
+    OPERATOR        0x22    <= (timestamptz, timestamp),
+    OPERATOR        0x23    = (timestamptz, timestamp),
+    OPERATOR        0x24    >= (timestamptz, timestamp),
+    OPERATOR        0x25    > (timestamptz, timestamp)
+;
diff --git a/contrib/btree_gin/btree_gin.c b/contrib/btree_gin/btree_gin.c
index 98663cb86117e..8c477d17e22ce 100644
--- a/contrib/btree_gin/btree_gin.c
+++ b/contrib/btree_gin/btree_gin.c
@@ -6,6 +6,7 @@
 #include <limits.h>
 
 #include "access/stratnum.h"
+#include "mb/pg_wchar.h"
 #include "utils/builtins.h"
 #include "utils/date.h"
 #include "utils/float.h"
@@ -13,20 +14,36 @@
 #include "utils/numeric.h"
 #include "utils/timestamp.h"
 #include "utils/uuid.h"
+#include "varatt.h"
 
 PG_MODULE_MAGIC_EXT(
 					.name = "btree_gin",
 					.version = PG_VERSION
 );
 
+/*
+ * Our opclasses use the same strategy numbers as btree (1-5) for same-type
+ * comparison operators.  For cross-type comparison operators, the
+ * low 4 bits of our strategy numbers are the btree strategy number,
+ * and the upper bits are a code for the right-hand-side data type.
+ */
+#define BTGIN_GET_BTREE_STRATEGY(strat)		((strat) & 0x0F)
+#define BTGIN_GET_RHS_TYPE_CODE(strat)		((strat) >> 4)
+
+/* extra data passed from gin_btree_extract_query to gin_btree_compare_prefix */
 typedef struct QueryInfo
 {
-	StrategyNumber strategy;
-	Datum		datum;
-	bool		is_varlena;
-	Datum		(*typecmp) (FunctionCallInfo);
+	StrategyNumber strategy;	/* operator strategy number */
+	Datum		orig_datum;		/* original query (comparison) datum */
+	Datum		entry_datum;	/* datum we reported as the entry value */
+	PGFunction	typecmp;		/* appropriate btree comparison function */
 } QueryInfo;
 
+typedef Datum (*btree_gin_convert_function) (Datum input);
+
+typedef Datum (*btree_gin_leftmost_function) (void);
+
+
 /*** GIN support functions shared by all datatypes ***/
 
 static Datum
@@ -36,6 +53,7 @@ gin_btree_extract_value(FunctionCallInfo fcinfo, bool is_varlena)
 	int32	   *nentries = (int32 *) PG_GETARG_POINTER(1);
 	Datum	   *entries = (Datum *) palloc(sizeof(Datum));
 
+	/* Ensure that values stored in the index are not toasted */
 	if (is_varlena)
 		datum = PointerGetDatum(PG_DETOAST_DATUM(datum));
 	entries[0] = datum;
@@ -44,19 +62,12 @@ gin_btree_extract_value(FunctionCallInfo fcinfo, bool is_varlena)
 	PG_RETURN_POINTER(entries);
 }
 
-/*
- * For BTGreaterEqualStrategyNumber, BTGreaterStrategyNumber, and
- * BTEqualStrategyNumber we want to start the index scan at the
- * supplied query datum, and work forward. For BTLessStrategyNumber
- * and BTLessEqualStrategyNumber, we need to start at the leftmost
- * key, and work forward until the supplied query datum (which must be
- * sent along inside the QueryInfo structure).
- */
 static Datum
 gin_btree_extract_query(FunctionCallInfo fcinfo,
-						bool is_varlena,
-						Datum (*leftmostvalue) (void),
-						Datum (*typecmp) (FunctionCallInfo))
+						btree_gin_leftmost_function leftmostvalue,
+						const bool *rhs_is_varlena,
+						const btree_gin_convert_function *cvt_fns,
+						const PGFunction *cmp_fns)
 {
 	Datum		datum = PG_GETARG_DATUM(0);
 	int32	   *nentries = (int32 *) PG_GETARG_POINTER(1);
@@ -65,21 +76,40 @@ gin_btree_extract_query(FunctionCallInfo fcinfo,
 	Pointer   **extra_data = (Pointer **) PG_GETARG_POINTER(4);
 	Datum	   *entries = (Datum *) palloc(sizeof(Datum));
 	QueryInfo  *data = (QueryInfo *) palloc(sizeof(QueryInfo));
-	bool	   *ptr_partialmatch;
+	bool	   *ptr_partialmatch = (bool *) palloc(sizeof(bool));
+	int			btree_strat,
+				rhs_code;
+
+	/*
+	 * Extract the btree strategy code and the RHS data type code from the
+	 * given strategy number.
+	 */
+	btree_strat = BTGIN_GET_BTREE_STRATEGY(strategy);
+	rhs_code = BTGIN_GET_RHS_TYPE_CODE(strategy);
 
+	/*
+	 * Detoast the comparison datum.  This isn't necessary for correctness,
+	 * but it can save repeat detoastings within the comparison function.
+	 */
+	if (rhs_is_varlena[rhs_code])
+		datum = PointerGetDatum(PG_DETOAST_DATUM(datum));
+
+	/* Prep single comparison key with possible partial-match flag */
 	*nentries = 1;
-	ptr_partialmatch = *partialmatch = (bool *) palloc(sizeof(bool));
+	*partialmatch = ptr_partialmatch;
 	*ptr_partialmatch = false;
-	if (is_varlena)
-		datum = PointerGetDatum(PG_DETOAST_DATUM(datum));
-	data->strategy = strategy;
-	data->datum = datum;
-	data->is_varlena = is_varlena;
-	data->typecmp = typecmp;
-	*extra_data = (Pointer *) palloc(sizeof(Pointer));
-	**extra_data = (Pointer) data;
 
-	switch (strategy)
+	/*
+	 * For BTGreaterEqualStrategyNumber, BTGreaterStrategyNumber, and
+	 * BTEqualStrategyNumber we want to start the index scan at the supplied
+	 * query datum, and work forward.  For BTLessStrategyNumber and
+	 * BTLessEqualStrategyNumber, we need to start at the leftmost key, and
+	 * work forward until the supplied query datum (which we'll send along
+	 * inside the QueryInfo structure).  Use partial match rules except for
+	 * BTEqualStrategyNumber without a conversion function.  (If there is a
+	 * conversion function, comparison to the entry value is not trustworthy.)
+	 */
+	switch (btree_strat)
 	{
 		case BTLessStrategyNumber:
 		case BTLessEqualStrategyNumber:
@@ -91,75 +121,106 @@ gin_btree_extract_query(FunctionCallInfo fcinfo,
 			*ptr_partialmatch = true;
 			/* FALLTHROUGH */
 		case BTEqualStrategyNumber:
-			entries[0] = datum;
+			/* If we have a conversion function, apply it */
+			if (cvt_fns && cvt_fns[rhs_code])
+			{
+				entries[0] = (*cvt_fns[rhs_code]) (datum);
+				*ptr_partialmatch = true;
+			}
+			else
+				entries[0] = datum;
 			break;
 		default:
 			elog(ERROR, "unrecognized strategy number: %d", strategy);
 	}
 
+	/* Fill "extra" data */
+	data->strategy = strategy;
+	data->orig_datum = datum;
+	data->entry_datum = entries[0];
+	data->typecmp = cmp_fns[rhs_code];
+	*extra_data = (Pointer *) palloc(sizeof(Pointer));
+	**extra_data = (Pointer) data;
+
 	PG_RETURN_POINTER(entries);
 }
 
-/*
- * Datum a is a value from extract_query method and for BTLess*
- * strategy it is a left-most value.  So, use original datum from QueryInfo
- * to decide to stop scanning or not.  Datum b is always from index.
- */
 static Datum
 gin_btree_compare_prefix(FunctionCallInfo fcinfo)
 {
-	Datum		a = PG_GETARG_DATUM(0);
-	Datum		b = PG_GETARG_DATUM(1);
+	Datum		partial_key PG_USED_FOR_ASSERTS_ONLY = PG_GETARG_DATUM(0);
+	Datum		key = PG_GETARG_DATUM(1);
 	QueryInfo  *data = (QueryInfo *) PG_GETARG_POINTER(3);
 	int32		res,
 				cmp;
 
+	/*
+	 * partial_key is only an approximation to the real comparison value,
+	 * especially if it's a leftmost value.  We can get an accurate answer by
+	 * doing a possibly-cross-type comparison to the real comparison value.
+	 * (Note that partial_key and key are of the indexed datatype while
+	 * orig_datum is of the query operator's RHS datatype.)
+	 *
+	 * But just to be sure that things are what we expect, let's assert that
+	 * partial_key is indeed what gin_btree_extract_query reported, so that
+	 * we'll notice if anyone ever changes the core code in a way that breaks
+	 * our assumptions.
+	 */
+	Assert(partial_key == data->entry_datum);
+
 	cmp = DatumGetInt32(CallerFInfoFunctionCall2(data->typecmp,
 												 fcinfo->flinfo,
 												 PG_GET_COLLATION(),
-												 (data->strategy == BTLessStrategyNumber ||
-												  data->strategy == BTLessEqualStrategyNumber)
-												 ? data->datum : a,
-												 b));
+												 data->orig_datum,
+												 key));
 
-	switch (data->strategy)
+	/*
+	 * Convert the comparison result to the correct thing for the search
+	 * operator strategy.  When dealing with cross-type comparisons, an
+	 * imprecise entry datum could lead GIN to start the scan just before the
+	 * first possible match, so we must continue the scan if the current index
+	 * entry doesn't satisfy the search condition for >= and > cases.  But if
+	 * that happens in an = search we can stop, because an imprecise entry
+	 * datum means that the search value is unrepresentable in the indexed
+	 * data type, so that there will be no exact matches.
+	 */
+	switch (BTGIN_GET_BTREE_STRATEGY(data->strategy))
 	{
 		case BTLessStrategyNumber:
 			/* If original datum > indexed one then return match */
 			if (cmp > 0)
 				res = 0;
 			else
-				res = 1;
+				res = 1;		/* end scan */
 			break;
 		case BTLessEqualStrategyNumber:
-			/* The same except equality */
+			/* If original datum >= indexed one then return match */
 			if (cmp >= 0)
 				res = 0;
 			else
-				res = 1;
+				res = 1;		/* end scan */
 			break;
 		case BTEqualStrategyNumber:
-			if (cmp != 0)
-				res = 1;
-			else
+			/* If original datum = indexed one then return match */
+			/* See above about why we can end scan when cmp < 0 */
+			if (cmp == 0)
 				res = 0;
+			else
+				res = 1;		/* end scan */
 			break;
 		case BTGreaterEqualStrategyNumber:
 			/* If original datum <= indexed one then return match */
 			if (cmp <= 0)
 				res = 0;
 			else
-				res = 1;
+				res = -1;		/* keep scanning */
 			break;
 		case BTGreaterStrategyNumber:
-			/* If original datum <= indexed one then return match */
-			/* If original datum == indexed one then continue scan */
+			/* If original datum < indexed one then return match */
 			if (cmp < 0)
 				res = 0;
-			else if (cmp == 0)
-				res = -1;
 			else
-				res = 1;
+				res = -1;		/* keep scanning */
 			break;
 		default:
 			elog(ERROR, "unrecognized strategy number: %d",
@@ -182,19 +243,20 @@ gin_btree_consistent(PG_FUNCTION_ARGS)
 
 /*** GIN_SUPPORT macro defines the datatype specific functions ***/
 
-#define GIN_SUPPORT(type, is_varlena, leftmostvalue, typecmp)				\
+#define GIN_SUPPORT(type, leftmostvalue, is_varlena, cvtfns, cmpfns)		\
 PG_FUNCTION_INFO_V1(gin_extract_value_##type);								\
 Datum																		\
 gin_extract_value_##type(PG_FUNCTION_ARGS)									\
 {																			\
-	return gin_btree_extract_value(fcinfo, is_varlena);						\
+	return gin_btree_extract_value(fcinfo, is_varlena[0]);					\
 }	\
 PG_FUNCTION_INFO_V1(gin_extract_query_##type);								\
 Datum																		\
 gin_extract_query_##type(PG_FUNCTION_ARGS)									\
 {																			\
 	return gin_btree_extract_query(fcinfo,									\
-								   is_varlena, leftmostvalue, typecmp);		\
+								   leftmostvalue, is_varlena,				\
+								   cvtfns, cmpfns);							\
 }	\
 PG_FUNCTION_INFO_V1(gin_compare_prefix_##type);								\
 Datum																		\
@@ -206,13 +268,66 @@ gin_compare_prefix_##type(PG_FUNCTION_ARGS)									\
 
 /*** Datatype specifications ***/
 
+/* Function to produce the least possible value of the indexed datatype */
 static Datum
 leftmostvalue_int2(void)
 {
 	return Int16GetDatum(SHRT_MIN);
 }
 
-GIN_SUPPORT(int2, false, leftmostvalue_int2, btint2cmp)
+/*
+ * For cross-type support, we must provide conversion functions that produce
+ * a Datum of the indexed datatype, since GIN requires the "entry" datums to
+ * be of that type.  If an exact conversion is not possible, produce a value
+ * that will lead GIN to find the first index entry that is greater than
+ * or equal to the actual comparison value.  (But rounding down is OK, so
+ * sometimes we might find an index entry that's just less than the
+ * comparison value.)
+ *
+ * For integer values, it's sufficient to clamp the input to be in-range.
+ *
+ * Note: for out-of-range input values, we could in theory detect that the
+ * search condition matches all or none of the index, and avoid a useless
+ * index descent in the latter case.  Such searches are probably rare though,
+ * so we don't contort this code enough to do that.
+ */
+static Datum
+cvt_int4_int2(Datum input)
+{
+	int32		val = DatumGetInt32(input);
+
+	val = Max(val, SHRT_MIN);
+	val = Min(val, SHRT_MAX);
+	return Int16GetDatum((int16) val);
+}
+
+static Datum
+cvt_int8_int2(Datum input)
+{
+	int64		val = DatumGetInt64(input);
+
+	val = Max(val, SHRT_MIN);
+	val = Min(val, SHRT_MAX);
+	return Int16GetDatum((int16) val);
+}
+
+/*
+ * RHS-type-is-varlena flags, conversion and comparison function arrays,
+ * indexed by high bits of the operator strategy number.  A NULL in the
+ * conversion function array indicates that no conversion is needed, which
+ * will always be the case for the zero'th entry.  Note that the cross-type
+ * comparison functions should be the ones with the indexed datatype second.
+ */
+static const bool int2_rhs_is_varlena[] =
+{false, false, false};
+
+static const btree_gin_convert_function int2_cvt_fns[] =
+{NULL, cvt_int4_int2, cvt_int8_int2};
+
+static const PGFunction int2_cmp_fns[] =
+{btint2cmp, btint42cmp, btint82cmp};
+
+GIN_SUPPORT(int2, leftmostvalue_int2, int2_rhs_is_varlena, int2_cvt_fns, int2_cmp_fns)
 
 static Datum
 leftmostvalue_int4(void)
@@ -220,7 +335,34 @@ leftmostvalue_int4(void)
 	return Int32GetDatum(INT_MIN);
 }
 
-GIN_SUPPORT(int4, false, leftmostvalue_int4, btint4cmp)
+static Datum
+cvt_int2_int4(Datum input)
+{
+	int16		val = DatumGetInt16(input);
+
+	return Int32GetDatum((int32) val);
+}
+
+static Datum
+cvt_int8_int4(Datum input)
+{
+	int64		val = DatumGetInt64(input);
+
+	val = Max(val, INT_MIN);
+	val = Min(val, INT_MAX);
+	return Int32GetDatum((int32) val);
+}
+
+static const bool int4_rhs_is_varlena[] =
+{false, false, false};
+
+static const btree_gin_convert_function int4_cvt_fns[] =
+{NULL, cvt_int2_int4, cvt_int8_int4};
+
+static const PGFunction int4_cmp_fns[] =
+{btint4cmp, btint24cmp, btint84cmp};
+
+GIN_SUPPORT(int4, leftmostvalue_int4, int4_rhs_is_varlena, int4_cvt_fns, int4_cmp_fns)
 
 static Datum
 leftmostvalue_int8(void)
@@ -228,7 +370,32 @@ leftmostvalue_int8(void)
 	return Int64GetDatum(PG_INT64_MIN);
 }
 
-GIN_SUPPORT(int8, false, leftmostvalue_int8, btint8cmp)
+static Datum
+cvt_int2_int8(Datum input)
+{
+	int16		val = DatumGetInt16(input);
+
+	return Int64GetDatum((int64) val);
+}
+
+static Datum
+cvt_int4_int8(Datum input)
+{
+	int32		val = DatumGetInt32(input);
+
+	return Int64GetDatum((int64) val);
+}
+
+static const bool int8_rhs_is_varlena[] =
+{false, false, false};
+
+static const btree_gin_convert_function int8_cvt_fns[] =
+{NULL, cvt_int2_int8, cvt_int4_int8};
+
+static const PGFunction int8_cmp_fns[] =
+{btint8cmp, btint28cmp, btint48cmp};
+
+GIN_SUPPORT(int8, leftmostvalue_int8, int8_rhs_is_varlena, int8_cvt_fns, int8_cmp_fns)
 
 static Datum
 leftmostvalue_float4(void)
@@ -236,7 +403,34 @@ leftmostvalue_float4(void)
 	return Float4GetDatum(-get_float4_infinity());
 }
 
-GIN_SUPPORT(float4, false, leftmostvalue_float4, btfloat4cmp)
+static Datum
+cvt_float8_float4(Datum input)
+{
+	float8		val = DatumGetFloat8(input);
+	float4		result;
+
+	/*
+	 * Assume that ordinary C conversion will produce a usable result.
+	 * (Compare dtof(), which raises error conditions that we don't need.)
+	 * Note that for inputs that aren't exactly representable as float4, it
+	 * doesn't matter whether the conversion rounds up or down.  That might
+	 * cause us to scan a few index entries that we'll reject as not matching,
+	 * but we won't miss any that should match.
+	 */
+	result = (float4) val;
+	return Float4GetDatum(result);
+}
+
+static const bool float4_rhs_is_varlena[] =
+{false, false};
+
+static const btree_gin_convert_function float4_cvt_fns[] =
+{NULL, cvt_float8_float4};
+
+static const PGFunction float4_cmp_fns[] =
+{btfloat4cmp, btfloat84cmp};
+
+GIN_SUPPORT(float4, leftmostvalue_float4, float4_rhs_is_varlena, float4_cvt_fns, float4_cmp_fns)
 
 static Datum
 leftmostvalue_float8(void)
@@ -244,7 +438,24 @@ leftmostvalue_float8(void)
 	return Float8GetDatum(-get_float8_infinity());
 }
 
-GIN_SUPPORT(float8, false, leftmostvalue_float8, btfloat8cmp)
+static Datum
+cvt_float4_float8(Datum input)
+{
+	float4		val = DatumGetFloat4(input);
+
+	return Float8GetDatum((float8) val);
+}
+
+static const bool float8_rhs_is_varlena[] =
+{false, false};
+
+static const btree_gin_convert_function float8_cvt_fns[] =
+{NULL, cvt_float4_float8};
+
+static const PGFunction float8_cmp_fns[] =
+{btfloat8cmp, btfloat48cmp};
+
+GIN_SUPPORT(float8, leftmostvalue_float8, float8_rhs_is_varlena, float8_cvt_fns, float8_cmp_fns)
 
 static Datum
 leftmostvalue_money(void)
@@ -252,7 +463,13 @@ leftmostvalue_money(void)
 	return Int64GetDatum(PG_INT64_MIN);
 }
 
-GIN_SUPPORT(money, false, leftmostvalue_money, cash_cmp)
+static const bool money_rhs_is_varlena[] =
+{false};
+
+static const PGFunction money_cmp_fns[] =
+{cash_cmp};
+
+GIN_SUPPORT(money, leftmostvalue_money, money_rhs_is_varlena, NULL, money_cmp_fns)
 
 static Datum
 leftmostvalue_oid(void)
@@ -260,7 +477,13 @@ leftmostvalue_oid(void)
 	return ObjectIdGetDatum(0);
 }
 
-GIN_SUPPORT(oid, false, leftmostvalue_oid, btoidcmp)
+static const bool oid_rhs_is_varlena[] =
+{false};
+
+static const PGFunction oid_cmp_fns[] =
+{btoidcmp};
+
+GIN_SUPPORT(oid, leftmostvalue_oid, oid_rhs_is_varlena, NULL, oid_cmp_fns)
 
 static Datum
 leftmostvalue_timestamp(void)
@@ -268,9 +491,75 @@ leftmostvalue_timestamp(void)
 	return TimestampGetDatum(DT_NOBEGIN);
 }
 
-GIN_SUPPORT(timestamp, false, leftmostvalue_timestamp, timestamp_cmp)
+static Datum
+cvt_date_timestamp(Datum input)
+{
+	DateADT		val = DatumGetDateADT(input);
+	Timestamp	result;
+	int			overflow;
 
-GIN_SUPPORT(timestamptz, false, leftmostvalue_timestamp, timestamp_cmp)
+	result = date2timestamp_opt_overflow(val, &overflow);
+	/* We can ignore the overflow result, since result is useful as-is */
+	return TimestampGetDatum(result);
+}
+
+static Datum
+cvt_timestamptz_timestamp(Datum input)
+{
+	TimestampTz val = DatumGetTimestampTz(input);
+	Timestamp	result;
+	int			overflow;
+
+	result = timestamptz2timestamp_opt_overflow(val, &overflow);
+	/* We can ignore the overflow result, since result is useful as-is */
+	return TimestampGetDatum(result);
+}
+
+static const bool timestamp_rhs_is_varlena[] =
+{false, false, false};
+
+static const btree_gin_convert_function timestamp_cvt_fns[] =
+{NULL, cvt_date_timestamp, cvt_timestamptz_timestamp};
+
+static const PGFunction timestamp_cmp_fns[] =
+{timestamp_cmp, date_cmp_timestamp, timestamptz_cmp_timestamp};
+
+GIN_SUPPORT(timestamp, leftmostvalue_timestamp, timestamp_rhs_is_varlena, timestamp_cvt_fns, timestamp_cmp_fns)
+
+static Datum
+cvt_date_timestamptz(Datum input)
+{
+	DateADT		val = DatumGetDateADT(input);
+	TimestampTz result;
+	int			overflow;
+
+	result = date2timestamptz_opt_overflow(val, &overflow);
+	/* We can ignore the overflow result, since result is useful as-is */
+	return TimestampTzGetDatum(result);
+}
+
+static Datum
+cvt_timestamp_timestamptz(Datum input)
+{
+	Timestamp	val = DatumGetTimestamp(input);
+	TimestampTz result;
+	int			overflow;
+
+	result = timestamp2timestamptz_opt_overflow(val, &overflow);
+	/* We can ignore the overflow result, since result is useful as-is */
+	return TimestampTzGetDatum(result);
+}
+
+static const bool timestamptz_rhs_is_varlena[] =
+{false, false, false};
+
+static const btree_gin_convert_function timestamptz_cvt_fns[] =
+{NULL, cvt_date_timestamptz, cvt_timestamp_timestamptz};
+
+static const PGFunction timestamptz_cmp_fns[] =
+{timestamp_cmp, date_cmp_timestamptz, timestamp_cmp_timestamptz};
+
+GIN_SUPPORT(timestamptz, leftmostvalue_timestamp, timestamptz_rhs_is_varlena, timestamptz_cvt_fns, timestamptz_cmp_fns)
 
 static Datum
 leftmostvalue_time(void)
@@ -278,7 +567,13 @@ leftmostvalue_time(void)
 	return TimeADTGetDatum(0);
 }
 
-GIN_SUPPORT(time, false, leftmostvalue_time, time_cmp)
+static const bool time_rhs_is_varlena[] =
+{false};
+
+static const PGFunction time_cmp_fns[] =
+{time_cmp};
+
+GIN_SUPPORT(time, leftmostvalue_time, time_rhs_is_varlena, NULL, time_cmp_fns)
 
 static Datum
 leftmostvalue_timetz(void)
@@ -291,7 +586,13 @@ leftmostvalue_timetz(void)
 	return TimeTzADTPGetDatum(v);
 }
 
-GIN_SUPPORT(timetz, false, leftmostvalue_timetz, timetz_cmp)
+static const bool timetz_rhs_is_varlena[] =
+{false};
+
+static const PGFunction timetz_cmp_fns[] =
+{timetz_cmp};
+
+GIN_SUPPORT(timetz, leftmostvalue_timetz, timetz_rhs_is_varlena, NULL, timetz_cmp_fns)
 
 static Datum
 leftmostvalue_date(void)
@@ -299,7 +600,40 @@ leftmostvalue_date(void)
 	return DateADTGetDatum(DATEVAL_NOBEGIN);
 }
 
-GIN_SUPPORT(date, false, leftmostvalue_date, date_cmp)
+static Datum
+cvt_timestamp_date(Datum input)
+{
+	Timestamp	val = DatumGetTimestamp(input);
+	DateADT		result;
+	int			overflow;
+
+	result = timestamp2date_opt_overflow(val, &overflow);
+	/* We can ignore the overflow result, since result is useful as-is */
+	return DateADTGetDatum(result);
+}
+
+static Datum
+cvt_timestamptz_date(Datum input)
+{
+	TimestampTz val = DatumGetTimestampTz(input);
+	DateADT		result;
+	int			overflow;
+
+	result = timestamptz2date_opt_overflow(val, &overflow);
+	/* We can ignore the overflow result, since result is useful as-is */
+	return DateADTGetDatum(result);
+}
+
+static const bool date_rhs_is_varlena[] =
+{false, false, false};
+
+static const btree_gin_convert_function date_cvt_fns[] =
+{NULL, cvt_timestamp_date, cvt_timestamptz_date};
+
+static const PGFunction date_cmp_fns[] =
+{date_cmp, timestamp_cmp_date, timestamptz_cmp_date};
+
+GIN_SUPPORT(date, leftmostvalue_date, date_rhs_is_varlena, date_cvt_fns, date_cmp_fns)
 
 static Datum
 leftmostvalue_interval(void)
@@ -311,7 +645,13 @@ leftmostvalue_interval(void)
 	return IntervalPGetDatum(v);
 }
 
-GIN_SUPPORT(interval, false, leftmostvalue_interval, interval_cmp)
+static const bool interval_rhs_is_varlena[] =
+{false};
+
+static const PGFunction interval_cmp_fns[] =
+{interval_cmp};
+
+GIN_SUPPORT(interval, leftmostvalue_interval, interval_rhs_is_varlena, NULL, interval_cmp_fns)
 
 static Datum
 leftmostvalue_macaddr(void)
@@ -321,7 +661,13 @@ leftmostvalue_macaddr(void)
 	return MacaddrPGetDatum(v);
 }
 
-GIN_SUPPORT(macaddr, false, leftmostvalue_macaddr, macaddr_cmp)
+static const bool macaddr_rhs_is_varlena[] =
+{false};
+
+static const PGFunction macaddr_cmp_fns[] =
+{macaddr_cmp};
+
+GIN_SUPPORT(macaddr, leftmostvalue_macaddr, macaddr_rhs_is_varlena, NULL, macaddr_cmp_fns)
 
 static Datum
 leftmostvalue_macaddr8(void)
@@ -331,7 +677,13 @@ leftmostvalue_macaddr8(void)
 	return Macaddr8PGetDatum(v);
 }
 
-GIN_SUPPORT(macaddr8, false, leftmostvalue_macaddr8, macaddr8_cmp)
+static const bool macaddr8_rhs_is_varlena[] =
+{false};
+
+static const PGFunction macaddr8_cmp_fns[] =
+{macaddr8_cmp};
+
+GIN_SUPPORT(macaddr8, leftmostvalue_macaddr8, macaddr8_rhs_is_varlena, NULL, macaddr8_cmp_fns)
 
 static Datum
 leftmostvalue_inet(void)
@@ -339,9 +691,21 @@ leftmostvalue_inet(void)
 	return DirectFunctionCall1(inet_in, CStringGetDatum("0.0.0.0/0"));
 }
 
-GIN_SUPPORT(inet, true, leftmostvalue_inet, network_cmp)
+static const bool inet_rhs_is_varlena[] =
+{true};
+
+static const PGFunction inet_cmp_fns[] =
+{network_cmp};
+
+GIN_SUPPORT(inet, leftmostvalue_inet, inet_rhs_is_varlena, NULL, inet_cmp_fns)
 
-GIN_SUPPORT(cidr, true, leftmostvalue_inet, network_cmp)
+static const bool cidr_rhs_is_varlena[] =
+{true};
+
+static const PGFunction cidr_cmp_fns[] =
+{network_cmp};
+
+GIN_SUPPORT(cidr, leftmostvalue_inet, cidr_rhs_is_varlena, NULL, cidr_cmp_fns)
 
 static Datum
 leftmostvalue_text(void)
@@ -349,9 +713,32 @@ leftmostvalue_text(void)
 	return PointerGetDatum(cstring_to_text_with_len("", 0));
 }
 
-GIN_SUPPORT(text, true, leftmostvalue_text, bttextcmp)
+static Datum
+cvt_name_text(Datum input)
+{
+	Name		val = DatumGetName(input);
+
+	return PointerGetDatum(cstring_to_text(NameStr(*val)));
+}
 
-GIN_SUPPORT(bpchar, true, leftmostvalue_text, bpcharcmp)
+static const bool text_rhs_is_varlena[] =
+{true, false};
+
+static const btree_gin_convert_function text_cvt_fns[] =
+{NULL, cvt_name_text};
+
+static const PGFunction text_cmp_fns[] =
+{bttextcmp, btnametextcmp};
+
+GIN_SUPPORT(text, leftmostvalue_text, text_rhs_is_varlena, text_cvt_fns, text_cmp_fns)
+
+static const bool bpchar_rhs_is_varlena[] =
+{true};
+
+static const PGFunction bpchar_cmp_fns[] =
+{bpcharcmp};
+
+GIN_SUPPORT(bpchar, leftmostvalue_text, bpchar_rhs_is_varlena, NULL, bpchar_cmp_fns)
 
 static Datum
 leftmostvalue_char(void)
@@ -359,9 +746,21 @@ leftmostvalue_char(void)
 	return CharGetDatum(0);
 }
 
-GIN_SUPPORT(char, false, leftmostvalue_char, btcharcmp)
+static const bool char_rhs_is_varlena[] =
+{false};
 
-GIN_SUPPORT(bytea, true, leftmostvalue_text, byteacmp)
+static const PGFunction char_cmp_fns[] =
+{btcharcmp};
+
+GIN_SUPPORT(char, leftmostvalue_char, char_rhs_is_varlena, NULL, char_cmp_fns)
+
+static const bool bytea_rhs_is_varlena[] =
+{true};
+
+static const PGFunction bytea_cmp_fns[] =
+{byteacmp};
+
+GIN_SUPPORT(bytea, leftmostvalue_text, bytea_rhs_is_varlena, NULL, bytea_cmp_fns)
 
 static Datum
 leftmostvalue_bit(void)
@@ -372,7 +771,13 @@ leftmostvalue_bit(void)
 							   Int32GetDatum(-1));
 }
 
-GIN_SUPPORT(bit, true, leftmostvalue_bit, bitcmp)
+static const bool bit_rhs_is_varlena[] =
+{true};
+
+static const PGFunction bit_cmp_fns[] =
+{bitcmp};
+
+GIN_SUPPORT(bit, leftmostvalue_bit, bit_rhs_is_varlena, NULL, bit_cmp_fns)
 
 static Datum
 leftmostvalue_varbit(void)
@@ -383,7 +788,13 @@ leftmostvalue_varbit(void)
 							   Int32GetDatum(-1));
 }
 
-GIN_SUPPORT(varbit, true, leftmostvalue_varbit, bitcmp)
+static const bool varbit_rhs_is_varlena[] =
+{true};
+
+static const PGFunction varbit_cmp_fns[] =
+{bitcmp};
+
+GIN_SUPPORT(varbit, leftmostvalue_varbit, varbit_rhs_is_varlena, NULL, varbit_cmp_fns)
 
 /*
  * Numeric type hasn't a real left-most value, so we use PointerGetDatum(NULL)
@@ -428,7 +839,13 @@ leftmostvalue_numeric(void)
 	return PointerGetDatum(NULL);
 }
 
-GIN_SUPPORT(numeric, true, leftmostvalue_numeric, gin_numeric_cmp)
+static const bool numeric_rhs_is_varlena[] =
+{true};
+
+static const PGFunction numeric_cmp_fns[] =
+{gin_numeric_cmp};
+
+GIN_SUPPORT(numeric, leftmostvalue_numeric, numeric_rhs_is_varlena, NULL, numeric_cmp_fns)
 
 /*
  * Use a similar trick to that used for numeric for enums, since we don't
@@ -477,7 +894,13 @@ leftmostvalue_enum(void)
 	return ObjectIdGetDatum(InvalidOid);
 }
 
-GIN_SUPPORT(anyenum, false, leftmostvalue_enum, gin_enum_cmp)
+static const bool enum_rhs_is_varlena[] =
+{false};
+
+static const PGFunction enum_cmp_fns[] =
+{gin_enum_cmp};
+
+GIN_SUPPORT(anyenum, leftmostvalue_enum, enum_rhs_is_varlena, NULL, enum_cmp_fns)
 
 static Datum
 leftmostvalue_uuid(void)
@@ -491,7 +914,13 @@ leftmostvalue_uuid(void)
 	return UUIDPGetDatum(retval);
 }
 
-GIN_SUPPORT(uuid, false, leftmostvalue_uuid, uuid_cmp)
+static const bool uuid_rhs_is_varlena[] =
+{false};
+
+static const PGFunction uuid_cmp_fns[] =
+{uuid_cmp};
+
+GIN_SUPPORT(uuid, leftmostvalue_uuid, uuid_rhs_is_varlena, NULL, uuid_cmp_fns)
 
 static Datum
 leftmostvalue_name(void)
@@ -501,7 +930,37 @@ leftmostvalue_name(void)
 	return NameGetDatum(result);
 }
 
-GIN_SUPPORT(name, false, leftmostvalue_name, btnamecmp)
+static Datum
+cvt_text_name(Datum input)
+{
+	text	   *val = DatumGetTextPP(input);
+	NameData   *result = (NameData *) palloc0(NAMEDATALEN);
+	int			len = VARSIZE_ANY_EXHDR(val);
+
+	/*
+	 * Truncate oversize input.  We're assuming this will produce a result
+	 * considered less than the original.  That could be a bad assumption in
+	 * some collations, but fortunately an index on "name" is generally going
+	 * to use C collation.
+	 */
+	if (len >= NAMEDATALEN)
+		len = pg_mbcliplen(VARDATA_ANY(val), len, NAMEDATALEN - 1);
+
+	memcpy(NameStr(*result), VARDATA_ANY(val), len);
+
+	return NameGetDatum(result);
+}
+
+static const bool name_rhs_is_varlena[] =
+{false, true};
+
+static const btree_gin_convert_function name_cvt_fns[] =
+{NULL, cvt_text_name};
+
+static const PGFunction name_cmp_fns[] =
+{btnamecmp, bttextnamecmp};
+
+GIN_SUPPORT(name, leftmostvalue_name, name_rhs_is_varlena, name_cvt_fns, name_cmp_fns)
 
 static Datum
 leftmostvalue_bool(void)
@@ -509,4 +968,10 @@ leftmostvalue_bool(void)
 	return BoolGetDatum(false);
 }
 
-GIN_SUPPORT(bool, false, leftmostvalue_bool, btboolcmp)
+static const bool bool_rhs_is_varlena[] =
+{false};
+
+static const PGFunction bool_cmp_fns[] =
+{btboolcmp};
+
+GIN_SUPPORT(bool, leftmostvalue_bool, bool_rhs_is_varlena, NULL, bool_cmp_fns)
diff --git a/contrib/btree_gin/btree_gin.control b/contrib/btree_gin/btree_gin.control
index 67d0c997d8d26..0c77c81727117 100644
--- a/contrib/btree_gin/btree_gin.control
+++ b/contrib/btree_gin/btree_gin.control
@@ -1,6 +1,6 @@
 # btree_gin extension
 comment = 'support for indexing common datatypes in GIN'
-default_version = '1.3'
+default_version = '1.4'
 module_pathname = '$libdir/btree_gin'
 relocatable = true
 trusted = true
diff --git a/contrib/btree_gin/expected/date.out b/contrib/btree_gin/expected/date.out
index 40dfa308cf753..e69c1da2000f2 100644
--- a/contrib/btree_gin/expected/date.out
+++ b/contrib/btree_gin/expected/date.out
@@ -49,3 +49,365 @@ SELECT * FROM test_date WHERE i>'2004-10-26'::date ORDER BY i;
  10-28-2004
 (2 rows)
 
+explain (costs off)
+SELECT * FROM test_date WHERE i<'2004-10-26'::timestamp ORDER BY i;
+                                       QUERY PLAN                                        
+-----------------------------------------------------------------------------------------
+ Sort
+   Sort Key: i
+   ->  Bitmap Heap Scan on test_date
+         Recheck Cond: (i < 'Tue Oct 26 00:00:00 2004'::timestamp without time zone)
+         ->  Bitmap Index Scan on idx_date
+               Index Cond: (i < 'Tue Oct 26 00:00:00 2004'::timestamp without time zone)
+(6 rows)
+
+SELECT * FROM test_date WHERE i<'2004-10-26'::timestamp ORDER BY i;
+     i      
+------------
+ 10-23-2004
+ 10-24-2004
+ 10-25-2004
+(3 rows)
+
+SELECT * FROM test_date WHERE i<='2004-10-26'::timestamp ORDER BY i;
+     i      
+------------
+ 10-23-2004
+ 10-24-2004
+ 10-25-2004
+ 10-26-2004
+(4 rows)
+
+SELECT * FROM test_date WHERE i='2004-10-26'::timestamp ORDER BY i;
+     i      
+------------
+ 10-26-2004
+(1 row)
+
+SELECT * FROM test_date WHERE i>='2004-10-26'::timestamp ORDER BY i;
+     i      
+------------
+ 10-26-2004
+ 10-27-2004
+ 10-28-2004
+(3 rows)
+
+SELECT * FROM test_date WHERE i>'2004-10-26'::timestamp ORDER BY i;
+     i      
+------------
+ 10-27-2004
+ 10-28-2004
+(2 rows)
+
+explain (costs off)
+SELECT * FROM test_date WHERE i<'2004-10-26'::timestamptz ORDER BY i;
+                                        QUERY PLAN                                        
+------------------------------------------------------------------------------------------
+ Sort
+   Sort Key: i
+   ->  Bitmap Heap Scan on test_date
+         Recheck Cond: (i < 'Tue Oct 26 00:00:00 2004 PDT'::timestamp with time zone)
+         ->  Bitmap Index Scan on idx_date
+               Index Cond: (i < 'Tue Oct 26 00:00:00 2004 PDT'::timestamp with time zone)
+(6 rows)
+
+SELECT * FROM test_date WHERE i<'2004-10-26'::timestamptz ORDER BY i;
+     i      
+------------
+ 10-23-2004
+ 10-24-2004
+ 10-25-2004
+(3 rows)
+
+SELECT * FROM test_date WHERE i<='2004-10-26'::timestamptz ORDER BY i;
+     i      
+------------
+ 10-23-2004
+ 10-24-2004
+ 10-25-2004
+ 10-26-2004
+(4 rows)
+
+SELECT * FROM test_date WHERE i='2004-10-26'::timestamptz ORDER BY i;
+     i      
+------------
+ 10-26-2004
+(1 row)
+
+SELECT * FROM test_date WHERE i>='2004-10-26'::timestamptz ORDER BY i;
+     i      
+------------
+ 10-26-2004
+ 10-27-2004
+ 10-28-2004
+(3 rows)
+
+SELECT * FROM test_date WHERE i>'2004-10-26'::timestamptz ORDER BY i;
+     i      
+------------
+ 10-27-2004
+ 10-28-2004
+(2 rows)
+
+-- Check endpoint and out-of-range cases
+INSERT INTO test_date VALUES ('-infinity'), ('infinity');
+SELECT gin_clean_pending_list('idx_date');
+ gin_clean_pending_list 
+------------------------
+                      1
+(1 row)
+
+SELECT * FROM test_date WHERE i<'-infinity'::timestamp ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_date WHERE i<='-infinity'::timestamp ORDER BY i;
+     i     
+-----------
+ -infinity
+(1 row)
+
+SELECT * FROM test_date WHERE i='-infinity'::timestamp ORDER BY i;
+     i     
+-----------
+ -infinity
+(1 row)
+
+SELECT * FROM test_date WHERE i>='-infinity'::timestamp ORDER BY i;
+     i      
+------------
+ -infinity
+ 10-23-2004
+ 10-24-2004
+ 10-25-2004
+ 10-26-2004
+ 10-27-2004
+ 10-28-2004
+ infinity
+(8 rows)
+
+SELECT * FROM test_date WHERE i>'-infinity'::timestamp ORDER BY i;
+     i      
+------------
+ 10-23-2004
+ 10-24-2004
+ 10-25-2004
+ 10-26-2004
+ 10-27-2004
+ 10-28-2004
+ infinity
+(7 rows)
+
+SELECT * FROM test_date WHERE i<'infinity'::timestamp ORDER BY i;
+     i      
+------------
+ -infinity
+ 10-23-2004
+ 10-24-2004
+ 10-25-2004
+ 10-26-2004
+ 10-27-2004
+ 10-28-2004
+(7 rows)
+
+SELECT * FROM test_date WHERE i<='infinity'::timestamp ORDER BY i;
+     i      
+------------
+ -infinity
+ 10-23-2004
+ 10-24-2004
+ 10-25-2004
+ 10-26-2004
+ 10-27-2004
+ 10-28-2004
+ infinity
+(8 rows)
+
+SELECT * FROM test_date WHERE i='infinity'::timestamp ORDER BY i;
+    i     
+----------
+ infinity
+(1 row)
+
+SELECT * FROM test_date WHERE i>='infinity'::timestamp ORDER BY i;
+    i     
+----------
+ infinity
+(1 row)
+
+SELECT * FROM test_date WHERE i>'infinity'::timestamp ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_date WHERE i<'-infinity'::timestamptz ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_date WHERE i<='-infinity'::timestamptz ORDER BY i;
+     i     
+-----------
+ -infinity
+(1 row)
+
+SELECT * FROM test_date WHERE i='-infinity'::timestamptz ORDER BY i;
+     i     
+-----------
+ -infinity
+(1 row)
+
+SELECT * FROM test_date WHERE i>='-infinity'::timestamptz ORDER BY i;
+     i      
+------------
+ -infinity
+ 10-23-2004
+ 10-24-2004
+ 10-25-2004
+ 10-26-2004
+ 10-27-2004
+ 10-28-2004
+ infinity
+(8 rows)
+
+SELECT * FROM test_date WHERE i>'-infinity'::timestamptz ORDER BY i;
+     i      
+------------
+ 10-23-2004
+ 10-24-2004
+ 10-25-2004
+ 10-26-2004
+ 10-27-2004
+ 10-28-2004
+ infinity
+(7 rows)
+
+SELECT * FROM test_date WHERE i<'infinity'::timestamptz ORDER BY i;
+     i      
+------------
+ -infinity
+ 10-23-2004
+ 10-24-2004
+ 10-25-2004
+ 10-26-2004
+ 10-27-2004
+ 10-28-2004
+(7 rows)
+
+SELECT * FROM test_date WHERE i<='infinity'::timestamptz ORDER BY i;
+     i      
+------------
+ -infinity
+ 10-23-2004
+ 10-24-2004
+ 10-25-2004
+ 10-26-2004
+ 10-27-2004
+ 10-28-2004
+ infinity
+(8 rows)
+
+SELECT * FROM test_date WHERE i='infinity'::timestamptz ORDER BY i;
+    i     
+----------
+ infinity
+(1 row)
+
+SELECT * FROM test_date WHERE i>='infinity'::timestamptz ORDER BY i;
+    i     
+----------
+ infinity
+(1 row)
+
+SELECT * FROM test_date WHERE i>'infinity'::timestamptz ORDER BY i;
+ i 
+---
+(0 rows)
+
+-- Check rounding cases
+-- '2004-10-25 00:00:01' rounds to '2004-10-25' for date.
+-- '2004-10-25 23:59:59' also rounds to '2004-10-25',
+-- so it's the same case as '2004-10-25 00:00:01'
+SELECT * FROM test_date WHERE i < '2004-10-25 00:00:01'::timestamp ORDER BY i;
+     i      
+------------
+ -infinity
+ 10-23-2004
+ 10-24-2004
+ 10-25-2004
+(4 rows)
+
+SELECT * FROM test_date WHERE i <= '2004-10-25 00:00:01'::timestamp ORDER BY i;
+     i      
+------------
+ -infinity
+ 10-23-2004
+ 10-24-2004
+ 10-25-2004
+(4 rows)
+
+SELECT * FROM test_date WHERE i = '2004-10-25 00:00:01'::timestamp ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_date WHERE i > '2004-10-25 00:00:01'::timestamp ORDER BY i;
+     i      
+------------
+ 10-26-2004
+ 10-27-2004
+ 10-28-2004
+ infinity
+(4 rows)
+
+SELECT * FROM test_date WHERE i >= '2004-10-25 00:00:01'::timestamp ORDER BY i;
+     i      
+------------
+ 10-26-2004
+ 10-27-2004
+ 10-28-2004
+ infinity
+(4 rows)
+
+SELECT * FROM test_date WHERE i < '2004-10-25 00:00:01'::timestamptz ORDER BY i;
+     i      
+------------
+ -infinity
+ 10-23-2004
+ 10-24-2004
+ 10-25-2004
+(4 rows)
+
+SELECT * FROM test_date WHERE i <= '2004-10-25 00:00:01'::timestamptz ORDER BY i;
+     i      
+------------
+ -infinity
+ 10-23-2004
+ 10-24-2004
+ 10-25-2004
+(4 rows)
+
+SELECT * FROM test_date WHERE i = '2004-10-25 00:00:01'::timestamptz ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_date WHERE i > '2004-10-25 00:00:01'::timestamptz ORDER BY i;
+     i      
+------------
+ 10-26-2004
+ 10-27-2004
+ 10-28-2004
+ infinity
+(4 rows)
+
+SELECT * FROM test_date WHERE i >= '2004-10-25 00:00:01'::timestamptz ORDER BY i;
+     i      
+------------
+ 10-26-2004
+ 10-27-2004
+ 10-28-2004
+ infinity
+(4 rows)
+
diff --git a/contrib/btree_gin/expected/float4.out b/contrib/btree_gin/expected/float4.out
index 7b9134fcd4bdc..c8bb04e59be9b 100644
--- a/contrib/btree_gin/expected/float4.out
+++ b/contrib/btree_gin/expected/float4.out
@@ -42,3 +42,324 @@ SELECT * FROM test_float4 WHERE i>1::float4 ORDER BY i;
  3
 (2 rows)
 
+explain (costs off)
+SELECT * FROM test_float4 WHERE i<1::float8 ORDER BY i;
+                      QUERY PLAN                       
+-------------------------------------------------------
+ Sort
+   Sort Key: i
+   ->  Bitmap Heap Scan on test_float4
+         Recheck Cond: (i < '1'::double precision)
+         ->  Bitmap Index Scan on idx_float4
+               Index Cond: (i < '1'::double precision)
+(6 rows)
+
+SELECT * FROM test_float4 WHERE i<1::float8 ORDER BY i;
+ i  
+----
+ -2
+ -1
+  0
+(3 rows)
+
+SELECT * FROM test_float4 WHERE i<=1::float8 ORDER BY i;
+ i  
+----
+ -2
+ -1
+  0
+  1
+(4 rows)
+
+SELECT * FROM test_float4 WHERE i=1::float8 ORDER BY i;
+ i 
+---
+ 1
+(1 row)
+
+SELECT * FROM test_float4 WHERE i>=1::float8 ORDER BY i;
+ i 
+---
+ 1
+ 2
+ 3
+(3 rows)
+
+SELECT * FROM test_float4 WHERE i>1::float8 ORDER BY i;
+ i 
+---
+ 2
+ 3
+(2 rows)
+
+-- Check endpoint and out-of-range cases
+INSERT INTO test_float4 VALUES ('NaN'), ('Inf'), ('-Inf');
+SELECT gin_clean_pending_list('idx_float4');
+ gin_clean_pending_list 
+------------------------
+                      1
+(1 row)
+
+SELECT * FROM test_float4 WHERE i<'-Inf'::float8 ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_float4 WHERE i<='-Inf'::float8 ORDER BY i;
+     i     
+-----------
+ -Infinity
+(1 row)
+
+SELECT * FROM test_float4 WHERE i='-Inf'::float8 ORDER BY i;
+     i     
+-----------
+ -Infinity
+(1 row)
+
+SELECT * FROM test_float4 WHERE i>='-Inf'::float8 ORDER BY i;
+     i     
+-----------
+ -Infinity
+        -2
+        -1
+         0
+         1
+         2
+         3
+  Infinity
+       NaN
+(9 rows)
+
+SELECT * FROM test_float4 WHERE i>'-Inf'::float8 ORDER BY i;
+    i     
+----------
+       -2
+       -1
+        0
+        1
+        2
+        3
+ Infinity
+      NaN
+(8 rows)
+
+SELECT * FROM test_float4 WHERE i<'Inf'::float8 ORDER BY i;
+     i     
+-----------
+ -Infinity
+        -2
+        -1
+         0
+         1
+         2
+         3
+(7 rows)
+
+SELECT * FROM test_float4 WHERE i<='Inf'::float8 ORDER BY i;
+     i     
+-----------
+ -Infinity
+        -2
+        -1
+         0
+         1
+         2
+         3
+  Infinity
+(8 rows)
+
+SELECT * FROM test_float4 WHERE i='Inf'::float8 ORDER BY i;
+    i     
+----------
+ Infinity
+(1 row)
+
+SELECT * FROM test_float4 WHERE i>='Inf'::float8 ORDER BY i;
+    i     
+----------
+ Infinity
+      NaN
+(2 rows)
+
+SELECT * FROM test_float4 WHERE i>'Inf'::float8 ORDER BY i;
+  i  
+-----
+ NaN
+(1 row)
+
+SELECT * FROM test_float4 WHERE i<'1e300'::float8 ORDER BY i;
+     i     
+-----------
+ -Infinity
+        -2
+        -1
+         0
+         1
+         2
+         3
+(7 rows)
+
+SELECT * FROM test_float4 WHERE i<='1e300'::float8 ORDER BY i;
+     i     
+-----------
+ -Infinity
+        -2
+        -1
+         0
+         1
+         2
+         3
+(7 rows)
+
+SELECT * FROM test_float4 WHERE i='1e300'::float8 ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_float4 WHERE i>='1e300'::float8 ORDER BY i;
+    i     
+----------
+ Infinity
+      NaN
+(2 rows)
+
+SELECT * FROM test_float4 WHERE i>'1e300'::float8 ORDER BY i;
+    i     
+----------
+ Infinity
+      NaN
+(2 rows)
+
+SELECT * FROM test_float4 WHERE i<'NaN'::float8 ORDER BY i;
+     i     
+-----------
+ -Infinity
+        -2
+        -1
+         0
+         1
+         2
+         3
+  Infinity
+(8 rows)
+
+SELECT * FROM test_float4 WHERE i<='NaN'::float8 ORDER BY i;
+     i     
+-----------
+ -Infinity
+        -2
+        -1
+         0
+         1
+         2
+         3
+  Infinity
+       NaN
+(9 rows)
+
+SELECT * FROM test_float4 WHERE i='NaN'::float8 ORDER BY i;
+  i  
+-----
+ NaN
+(1 row)
+
+SELECT * FROM test_float4 WHERE i>='NaN'::float8 ORDER BY i;
+  i  
+-----
+ NaN
+(1 row)
+
+SELECT * FROM test_float4 WHERE i>'NaN'::float8 ORDER BY i;
+ i 
+---
+(0 rows)
+
+-- Check rounding cases
+-- 1e-300 rounds to 0 for float4 but not for float8
+SELECT * FROM test_float4 WHERE i < -1e-300::float8 ORDER BY i;
+     i     
+-----------
+ -Infinity
+        -2
+        -1
+(3 rows)
+
+SELECT * FROM test_float4 WHERE i <= -1e-300::float8 ORDER BY i;
+     i     
+-----------
+ -Infinity
+        -2
+        -1
+(3 rows)
+
+SELECT * FROM test_float4 WHERE i = -1e-300::float8 ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_float4 WHERE i > -1e-300::float8 ORDER BY i;
+    i     
+----------
+        0
+        1
+        2
+        3
+ Infinity
+      NaN
+(6 rows)
+
+SELECT * FROM test_float4 WHERE i >= -1e-300::float8 ORDER BY i;
+    i     
+----------
+        0
+        1
+        2
+        3
+ Infinity
+      NaN
+(6 rows)
+
+SELECT * FROM test_float4 WHERE i < 1e-300::float8 ORDER BY i;
+     i     
+-----------
+ -Infinity
+        -2
+        -1
+         0
+(4 rows)
+
+SELECT * FROM test_float4 WHERE i <= 1e-300::float8 ORDER BY i;
+     i     
+-----------
+ -Infinity
+        -2
+        -1
+         0
+(4 rows)
+
+SELECT * FROM test_float4 WHERE i = 1e-300::float8 ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_float4 WHERE i > 1e-300::float8 ORDER BY i;
+    i     
+----------
+        1
+        2
+        3
+ Infinity
+      NaN
+(5 rows)
+
+SELECT * FROM test_float4 WHERE i >= 1e-300::float8 ORDER BY i;
+    i     
+----------
+        1
+        2
+        3
+ Infinity
+      NaN
+(5 rows)
+
diff --git a/contrib/btree_gin/expected/float8.out b/contrib/btree_gin/expected/float8.out
index a41d4f9f6bb05..b2877dfa3c1c2 100644
--- a/contrib/btree_gin/expected/float8.out
+++ b/contrib/btree_gin/expected/float8.out
@@ -42,3 +42,53 @@ SELECT * FROM test_float8 WHERE i>1::float8 ORDER BY i;
  3
 (2 rows)
 
+explain (costs off)
+SELECT * FROM test_float8 WHERE i<1::float4 ORDER BY i;
+                 QUERY PLAN                  
+---------------------------------------------
+ Sort
+   Sort Key: i
+   ->  Bitmap Heap Scan on test_float8
+         Recheck Cond: (i < '1'::real)
+         ->  Bitmap Index Scan on idx_float8
+               Index Cond: (i < '1'::real)
+(6 rows)
+
+SELECT * FROM test_float8 WHERE i<1::float4 ORDER BY i;
+ i  
+----
+ -2
+ -1
+  0
+(3 rows)
+
+SELECT * FROM test_float8 WHERE i<=1::float4 ORDER BY i;
+ i  
+----
+ -2
+ -1
+  0
+  1
+(4 rows)
+
+SELECT * FROM test_float8 WHERE i=1::float4 ORDER BY i;
+ i 
+---
+ 1
+(1 row)
+
+SELECT * FROM test_float8 WHERE i>=1::float4 ORDER BY i;
+ i 
+---
+ 1
+ 2
+ 3
+(3 rows)
+
+SELECT * FROM test_float8 WHERE i>1::float4 ORDER BY i;
+ i 
+---
+ 2
+ 3
+(2 rows)
+
diff --git a/contrib/btree_gin/expected/int2.out b/contrib/btree_gin/expected/int2.out
index 20d66a1b05545..bcfa68f671a25 100644
--- a/contrib/btree_gin/expected/int2.out
+++ b/contrib/btree_gin/expected/int2.out
@@ -42,3 +42,193 @@ SELECT * FROM test_int2 WHERE i>1::int2 ORDER BY i;
  3
 (2 rows)
 
+explain (costs off)
+SELECT * FROM test_int2 WHERE i<1::int4 ORDER BY i;
+                QUERY PLAN                 
+-------------------------------------------
+ Sort
+   Sort Key: i
+   ->  Bitmap Heap Scan on test_int2
+         Recheck Cond: (i < 1)
+         ->  Bitmap Index Scan on idx_int2
+               Index Cond: (i < 1)
+(6 rows)
+
+SELECT * FROM test_int2 WHERE i<1::int4 ORDER BY i;
+ i  
+----
+ -2
+ -1
+  0
+(3 rows)
+
+SELECT * FROM test_int2 WHERE i<=1::int4 ORDER BY i;
+ i  
+----
+ -2
+ -1
+  0
+  1
+(4 rows)
+
+SELECT * FROM test_int2 WHERE i=1::int4 ORDER BY i;
+ i 
+---
+ 1
+(1 row)
+
+SELECT * FROM test_int2 WHERE i>=1::int4 ORDER BY i;
+ i 
+---
+ 1
+ 2
+ 3
+(3 rows)
+
+SELECT * FROM test_int2 WHERE i>1::int4 ORDER BY i;
+ i 
+---
+ 2
+ 3
+(2 rows)
+
+explain (costs off)
+SELECT * FROM test_int2 WHERE i<1::int8 ORDER BY i;
+                 QUERY PLAN                  
+---------------------------------------------
+ Sort
+   Sort Key: i
+   ->  Bitmap Heap Scan on test_int2
+         Recheck Cond: (i < '1'::bigint)
+         ->  Bitmap Index Scan on idx_int2
+               Index Cond: (i < '1'::bigint)
+(6 rows)
+
+SELECT * FROM test_int2 WHERE i<1::int8 ORDER BY i;
+ i  
+----
+ -2
+ -1
+  0
+(3 rows)
+
+SELECT * FROM test_int2 WHERE i<=1::int8 ORDER BY i;
+ i  
+----
+ -2
+ -1
+  0
+  1
+(4 rows)
+
+SELECT * FROM test_int2 WHERE i=1::int8 ORDER BY i;
+ i 
+---
+ 1
+(1 row)
+
+SELECT * FROM test_int2 WHERE i>=1::int8 ORDER BY i;
+ i 
+---
+ 1
+ 2
+ 3
+(3 rows)
+
+SELECT * FROM test_int2 WHERE i>1::int8 ORDER BY i;
+ i 
+---
+ 2
+ 3
+(2 rows)
+
+-- Check endpoint and out-of-range cases
+INSERT INTO test_int2 VALUES ((-32768)::int2),(32767);
+SELECT gin_clean_pending_list('idx_int2');
+ gin_clean_pending_list 
+------------------------
+                      1
+(1 row)
+
+SELECT * FROM test_int2 WHERE i<(-32769)::int4 ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_int2 WHERE i<=(-32769)::int4 ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_int2 WHERE i=(-32769)::int4 ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_int2 WHERE i>=(-32769)::int4 ORDER BY i;
+   i    
+--------
+ -32768
+     -2
+     -1
+      0
+      1
+      2
+      3
+  32767
+(8 rows)
+
+SELECT * FROM test_int2 WHERE i>(-32769)::int4 ORDER BY i;
+   i    
+--------
+ -32768
+     -2
+     -1
+      0
+      1
+      2
+      3
+  32767
+(8 rows)
+
+SELECT * FROM test_int2 WHERE i<32768::int4 ORDER BY i;
+   i    
+--------
+ -32768
+     -2
+     -1
+      0
+      1
+      2
+      3
+  32767
+(8 rows)
+
+SELECT * FROM test_int2 WHERE i<=32768::int4 ORDER BY i;
+   i    
+--------
+ -32768
+     -2
+     -1
+      0
+      1
+      2
+      3
+  32767
+(8 rows)
+
+SELECT * FROM test_int2 WHERE i=32768::int4 ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_int2 WHERE i>=32768::int4 ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_int2 WHERE i>32768::int4 ORDER BY i;
+ i 
+---
+(0 rows)
+
diff --git a/contrib/btree_gin/expected/int4.out b/contrib/btree_gin/expected/int4.out
index 0f0122c6f5e03..e62791e18bdc2 100644
--- a/contrib/btree_gin/expected/int4.out
+++ b/contrib/btree_gin/expected/int4.out
@@ -42,3 +42,103 @@ SELECT * FROM test_int4 WHERE i>1::int4 ORDER BY i;
  3
 (2 rows)
 
+explain (costs off)
+SELECT * FROM test_int4 WHERE i<1::int2 ORDER BY i;
+                  QUERY PLAN                   
+-----------------------------------------------
+ Sort
+   Sort Key: i
+   ->  Bitmap Heap Scan on test_int4
+         Recheck Cond: (i < '1'::smallint)
+         ->  Bitmap Index Scan on idx_int4
+               Index Cond: (i < '1'::smallint)
+(6 rows)
+
+SELECT * FROM test_int4 WHERE i<1::int2 ORDER BY i;
+ i  
+----
+ -2
+ -1
+  0
+(3 rows)
+
+SELECT * FROM test_int4 WHERE i<=1::int2 ORDER BY i;
+ i  
+----
+ -2
+ -1
+  0
+  1
+(4 rows)
+
+SELECT * FROM test_int4 WHERE i=1::int2 ORDER BY i;
+ i 
+---
+ 1
+(1 row)
+
+SELECT * FROM test_int4 WHERE i>=1::int2 ORDER BY i;
+ i 
+---
+ 1
+ 2
+ 3
+(3 rows)
+
+SELECT * FROM test_int4 WHERE i>1::int2 ORDER BY i;
+ i 
+---
+ 2
+ 3
+(2 rows)
+
+explain (costs off)
+SELECT * FROM test_int4 WHERE i<1::int8 ORDER BY i;
+                 QUERY PLAN                  
+---------------------------------------------
+ Sort
+   Sort Key: i
+   ->  Bitmap Heap Scan on test_int4
+         Recheck Cond: (i < '1'::bigint)
+         ->  Bitmap Index Scan on idx_int4
+               Index Cond: (i < '1'::bigint)
+(6 rows)
+
+SELECT * FROM test_int4 WHERE i<1::int8 ORDER BY i;
+ i  
+----
+ -2
+ -1
+  0
+(3 rows)
+
+SELECT * FROM test_int4 WHERE i<=1::int8 ORDER BY i;
+ i  
+----
+ -2
+ -1
+  0
+  1
+(4 rows)
+
+SELECT * FROM test_int4 WHERE i=1::int8 ORDER BY i;
+ i 
+---
+ 1
+(1 row)
+
+SELECT * FROM test_int4 WHERE i>=1::int8 ORDER BY i;
+ i 
+---
+ 1
+ 2
+ 3
+(3 rows)
+
+SELECT * FROM test_int4 WHERE i>1::int8 ORDER BY i;
+ i 
+---
+ 2
+ 3
+(2 rows)
+
diff --git a/contrib/btree_gin/expected/int8.out b/contrib/btree_gin/expected/int8.out
index 307e19e7a056d..c9aceb9d357c6 100644
--- a/contrib/btree_gin/expected/int8.out
+++ b/contrib/btree_gin/expected/int8.out
@@ -42,3 +42,103 @@ SELECT * FROM test_int8 WHERE i>1::int8 ORDER BY i;
  3
 (2 rows)
 
+explain (costs off)
+SELECT * FROM test_int8 WHERE i<1::int2 ORDER BY i;
+                  QUERY PLAN                   
+-----------------------------------------------
+ Sort
+   Sort Key: i
+   ->  Bitmap Heap Scan on test_int8
+         Recheck Cond: (i < '1'::smallint)
+         ->  Bitmap Index Scan on idx_int8
+               Index Cond: (i < '1'::smallint)
+(6 rows)
+
+SELECT * FROM test_int8 WHERE i<1::int2 ORDER BY i;
+ i  
+----
+ -2
+ -1
+  0
+(3 rows)
+
+SELECT * FROM test_int8 WHERE i<=1::int2 ORDER BY i;
+ i  
+----
+ -2
+ -1
+  0
+  1
+(4 rows)
+
+SELECT * FROM test_int8 WHERE i=1::int2 ORDER BY i;
+ i 
+---
+ 1
+(1 row)
+
+SELECT * FROM test_int8 WHERE i>=1::int2 ORDER BY i;
+ i 
+---
+ 1
+ 2
+ 3
+(3 rows)
+
+SELECT * FROM test_int8 WHERE i>1::int2 ORDER BY i;
+ i 
+---
+ 2
+ 3
+(2 rows)
+
+explain (costs off)
+SELECT * FROM test_int8 WHERE i<1::int4 ORDER BY i;
+                QUERY PLAN                 
+-------------------------------------------
+ Sort
+   Sort Key: i
+   ->  Bitmap Heap Scan on test_int8
+         Recheck Cond: (i < 1)
+         ->  Bitmap Index Scan on idx_int8
+               Index Cond: (i < 1)
+(6 rows)
+
+SELECT * FROM test_int8 WHERE i<1::int4 ORDER BY i;
+ i  
+----
+ -2
+ -1
+  0
+(3 rows)
+
+SELECT * FROM test_int8 WHERE i<=1::int4 ORDER BY i;
+ i  
+----
+ -2
+ -1
+  0
+  1
+(4 rows)
+
+SELECT * FROM test_int8 WHERE i=1::int4 ORDER BY i;
+ i 
+---
+ 1
+(1 row)
+
+SELECT * FROM test_int8 WHERE i>=1::int4 ORDER BY i;
+ i 
+---
+ 1
+ 2
+ 3
+(3 rows)
+
+SELECT * FROM test_int8 WHERE i>1::int4 ORDER BY i;
+ i 
+---
+ 2
+ 3
+(2 rows)
+
diff --git a/contrib/btree_gin/expected/name.out b/contrib/btree_gin/expected/name.out
index 174de6576f0f0..3a30f62519c67 100644
--- a/contrib/btree_gin/expected/name.out
+++ b/contrib/btree_gin/expected/name.out
@@ -95,3 +95,62 @@ EXPLAIN (COSTS OFF) SELECT * FROM test_name WHERE i>'abc' ORDER BY i;
                Index Cond: (i > 'abc'::name)
 (6 rows)
 
+explain (costs off)
+SELECT * FROM test_name WHERE i<'abc'::text ORDER BY i;
+                 QUERY PLAN                  
+---------------------------------------------
+ Sort
+   Sort Key: i
+   ->  Bitmap Heap Scan on test_name
+         Recheck Cond: (i < 'abc'::text)
+         ->  Bitmap Index Scan on idx_name
+               Index Cond: (i < 'abc'::text)
+(6 rows)
+
+SELECT * FROM test_name WHERE i<'abc'::text ORDER BY i;
+  i  
+-----
+ a
+ ab
+ abb
+(3 rows)
+
+SELECT * FROM test_name WHERE i<='abc'::text ORDER BY i;
+  i  
+-----
+ a
+ ab
+ abb
+ abc
+(4 rows)
+
+SELECT * FROM test_name WHERE i='abc'::text ORDER BY i;
+  i  
+-----
+ abc
+(1 row)
+
+SELECT * FROM test_name WHERE i>='abc'::text ORDER BY i;
+  i  
+-----
+ abc
+ axy
+ xyz
+(3 rows)
+
+SELECT * FROM test_name WHERE i>'abc'::text ORDER BY i;
+  i  
+-----
+ axy
+ xyz
+(2 rows)
+
+SELECT * FROM test_name WHERE i<=repeat('abc', 100) ORDER BY i;
+  i  
+-----
+ a
+ ab
+ abb
+ abc
+(4 rows)
+
diff --git a/contrib/btree_gin/expected/text.out b/contrib/btree_gin/expected/text.out
index 3e31ad744d6aa..7f52f3db7b38e 100644
--- a/contrib/btree_gin/expected/text.out
+++ b/contrib/btree_gin/expected/text.out
@@ -42,3 +42,53 @@ SELECT * FROM test_text WHERE i>'abc' ORDER BY i;
  xyz
 (2 rows)
 
+explain (costs off)
+SELECT * FROM test_text WHERE i<'abc'::name COLLATE "default" ORDER BY i;
+                          QUERY PLAN                           
+---------------------------------------------------------------
+ Sort
+   Sort Key: i
+   ->  Bitmap Heap Scan on test_text
+         Recheck Cond: (i < 'abc'::name COLLATE "default")
+         ->  Bitmap Index Scan on idx_text
+               Index Cond: (i < 'abc'::name COLLATE "default")
+(6 rows)
+
+SELECT * FROM test_text WHERE i<'abc'::name COLLATE "default" ORDER BY i;
+  i  
+-----
+ a
+ ab
+ abb
+(3 rows)
+
+SELECT * FROM test_text WHERE i<='abc'::name COLLATE "default" ORDER BY i;
+  i  
+-----
+ a
+ ab
+ abb
+ abc
+(4 rows)
+
+SELECT * FROM test_text WHERE i='abc'::name COLLATE "default" ORDER BY i;
+  i  
+-----
+ abc
+(1 row)
+
+SELECT * FROM test_text WHERE i>='abc'::name COLLATE "default" ORDER BY i;
+  i  
+-----
+ abc
+ axy
+ xyz
+(3 rows)
+
+SELECT * FROM test_text WHERE i>'abc'::name COLLATE "default" ORDER BY i;
+  i  
+-----
+ axy
+ xyz
+(2 rows)
+
diff --git a/contrib/btree_gin/expected/timestamp.out b/contrib/btree_gin/expected/timestamp.out
index a236cdc94a9d2..b7565285e68ba 100644
--- a/contrib/btree_gin/expected/timestamp.out
+++ b/contrib/btree_gin/expected/timestamp.out
@@ -7,8 +7,8 @@ INSERT INTO test_timestamp VALUES
 	( '2004-10-26 04:55:08' ),
 	( '2004-10-26 05:55:08' ),
 	( '2004-10-26 08:55:08' ),
-	( '2004-10-26 09:55:08' ),
-	( '2004-10-26 10:55:08' )
+	( '2004-10-27 09:55:08' ),
+	( '2004-10-27 10:55:08' )
 ;
 CREATE INDEX idx_timestamp ON test_timestamp USING gin (i);
 SELECT * FROM test_timestamp WHERE i<'2004-10-26 08:55:08'::timestamp ORDER BY i;
@@ -38,14 +38,308 @@ SELECT * FROM test_timestamp WHERE i>='2004-10-26 08:55:08'::timestamp ORDER BY
             i             
 --------------------------
  Tue Oct 26 08:55:08 2004
- Tue Oct 26 09:55:08 2004
- Tue Oct 26 10:55:08 2004
+ Wed Oct 27 09:55:08 2004
+ Wed Oct 27 10:55:08 2004
 (3 rows)
 
 SELECT * FROM test_timestamp WHERE i>'2004-10-26 08:55:08'::timestamp ORDER BY i;
             i             
 --------------------------
- Tue Oct 26 09:55:08 2004
- Tue Oct 26 10:55:08 2004
+ Wed Oct 27 09:55:08 2004
+ Wed Oct 27 10:55:08 2004
 (2 rows)
 
+explain (costs off)
+SELECT * FROM test_timestamp WHERE i<'2004-10-27'::date ORDER BY i;
+                     QUERY PLAN                     
+----------------------------------------------------
+ Sort
+   Sort Key: i
+   ->  Bitmap Heap Scan on test_timestamp
+         Recheck Cond: (i < '10-27-2004'::date)
+         ->  Bitmap Index Scan on idx_timestamp
+               Index Cond: (i < '10-27-2004'::date)
+(6 rows)
+
+SELECT * FROM test_timestamp WHERE i<'2004-10-27'::date ORDER BY i;
+            i             
+--------------------------
+ Tue Oct 26 03:55:08 2004
+ Tue Oct 26 04:55:08 2004
+ Tue Oct 26 05:55:08 2004
+ Tue Oct 26 08:55:08 2004
+(4 rows)
+
+SELECT * FROM test_timestamp WHERE i<='2004-10-27'::date ORDER BY i;
+            i             
+--------------------------
+ Tue Oct 26 03:55:08 2004
+ Tue Oct 26 04:55:08 2004
+ Tue Oct 26 05:55:08 2004
+ Tue Oct 26 08:55:08 2004
+(4 rows)
+
+SELECT * FROM test_timestamp WHERE i='2004-10-27'::date ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_timestamp WHERE i>='2004-10-27'::date ORDER BY i;
+            i             
+--------------------------
+ Wed Oct 27 09:55:08 2004
+ Wed Oct 27 10:55:08 2004
+(2 rows)
+
+SELECT * FROM test_timestamp WHERE i>'2004-10-27'::date ORDER BY i;
+            i             
+--------------------------
+ Wed Oct 27 09:55:08 2004
+ Wed Oct 27 10:55:08 2004
+(2 rows)
+
+explain (costs off)
+SELECT * FROM test_timestamp WHERE i<'2004-10-26 08:55:08'::timestamptz ORDER BY i;
+                                        QUERY PLAN                                        
+------------------------------------------------------------------------------------------
+ Sort
+   Sort Key: i
+   ->  Bitmap Heap Scan on test_timestamp
+         Recheck Cond: (i < 'Tue Oct 26 08:55:08 2004 PDT'::timestamp with time zone)
+         ->  Bitmap Index Scan on idx_timestamp
+               Index Cond: (i < 'Tue Oct 26 08:55:08 2004 PDT'::timestamp with time zone)
+(6 rows)
+
+SELECT * FROM test_timestamp WHERE i<'2004-10-26 08:55:08'::timestamptz ORDER BY i;
+            i             
+--------------------------
+ Tue Oct 26 03:55:08 2004
+ Tue Oct 26 04:55:08 2004
+ Tue Oct 26 05:55:08 2004
+(3 rows)
+
+SELECT * FROM test_timestamp WHERE i<='2004-10-26 08:55:08'::timestamptz ORDER BY i;
+            i             
+--------------------------
+ Tue Oct 26 03:55:08 2004
+ Tue Oct 26 04:55:08 2004
+ Tue Oct 26 05:55:08 2004
+ Tue Oct 26 08:55:08 2004
+(4 rows)
+
+SELECT * FROM test_timestamp WHERE i='2004-10-26 08:55:08'::timestamptz ORDER BY i;
+            i             
+--------------------------
+ Tue Oct 26 08:55:08 2004
+(1 row)
+
+SELECT * FROM test_timestamp WHERE i>='2004-10-26 08:55:08'::timestamptz ORDER BY i;
+            i             
+--------------------------
+ Tue Oct 26 08:55:08 2004
+ Wed Oct 27 09:55:08 2004
+ Wed Oct 27 10:55:08 2004
+(3 rows)
+
+SELECT * FROM test_timestamp WHERE i>'2004-10-26 08:55:08'::timestamptz ORDER BY i;
+            i             
+--------------------------
+ Wed Oct 27 09:55:08 2004
+ Wed Oct 27 10:55:08 2004
+(2 rows)
+
+-- Check endpoint and out-of-range cases
+INSERT INTO test_timestamp VALUES ('-infinity'), ('infinity');
+SELECT gin_clean_pending_list('idx_timestamp');
+ gin_clean_pending_list 
+------------------------
+                      1
+(1 row)
+
+SELECT * FROM test_timestamp WHERE i<'-infinity'::date ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_timestamp WHERE i<='-infinity'::date ORDER BY i;
+     i     
+-----------
+ -infinity
+(1 row)
+
+SELECT * FROM test_timestamp WHERE i='-infinity'::date ORDER BY i;
+     i     
+-----------
+ -infinity
+(1 row)
+
+SELECT * FROM test_timestamp WHERE i>='-infinity'::date ORDER BY i;
+            i             
+--------------------------
+ -infinity
+ Tue Oct 26 03:55:08 2004
+ Tue Oct 26 04:55:08 2004
+ Tue Oct 26 05:55:08 2004
+ Tue Oct 26 08:55:08 2004
+ Wed Oct 27 09:55:08 2004
+ Wed Oct 27 10:55:08 2004
+ infinity
+(8 rows)
+
+SELECT * FROM test_timestamp WHERE i>'-infinity'::date ORDER BY i;
+            i             
+--------------------------
+ Tue Oct 26 03:55:08 2004
+ Tue Oct 26 04:55:08 2004
+ Tue Oct 26 05:55:08 2004
+ Tue Oct 26 08:55:08 2004
+ Wed Oct 27 09:55:08 2004
+ Wed Oct 27 10:55:08 2004
+ infinity
+(7 rows)
+
+SELECT * FROM test_timestamp WHERE i<'infinity'::date ORDER BY i;
+            i             
+--------------------------
+ -infinity
+ Tue Oct 26 03:55:08 2004
+ Tue Oct 26 04:55:08 2004
+ Tue Oct 26 05:55:08 2004
+ Tue Oct 26 08:55:08 2004
+ Wed Oct 27 09:55:08 2004
+ Wed Oct 27 10:55:08 2004
+(7 rows)
+
+SELECT * FROM test_timestamp WHERE i<='infinity'::date ORDER BY i;
+            i             
+--------------------------
+ -infinity
+ Tue Oct 26 03:55:08 2004
+ Tue Oct 26 04:55:08 2004
+ Tue Oct 26 05:55:08 2004
+ Tue Oct 26 08:55:08 2004
+ Wed Oct 27 09:55:08 2004
+ Wed Oct 27 10:55:08 2004
+ infinity
+(8 rows)
+
+SELECT * FROM test_timestamp WHERE i='infinity'::date ORDER BY i;
+    i     
+----------
+ infinity
+(1 row)
+
+SELECT * FROM test_timestamp WHERE i>='infinity'::date ORDER BY i;
+    i     
+----------
+ infinity
+(1 row)
+
+SELECT * FROM test_timestamp WHERE i>'infinity'::date ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_timestamp WHERE i<'-infinity'::timestamptz ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_timestamp WHERE i<='-infinity'::timestamptz ORDER BY i;
+     i     
+-----------
+ -infinity
+(1 row)
+
+SELECT * FROM test_timestamp WHERE i='-infinity'::timestamptz ORDER BY i;
+     i     
+-----------
+ -infinity
+(1 row)
+
+SELECT * FROM test_timestamp WHERE i>='-infinity'::timestamptz ORDER BY i;
+            i             
+--------------------------
+ -infinity
+ Tue Oct 26 03:55:08 2004
+ Tue Oct 26 04:55:08 2004
+ Tue Oct 26 05:55:08 2004
+ Tue Oct 26 08:55:08 2004
+ Wed Oct 27 09:55:08 2004
+ Wed Oct 27 10:55:08 2004
+ infinity
+(8 rows)
+
+SELECT * FROM test_timestamp WHERE i>'-infinity'::timestamptz ORDER BY i;
+            i             
+--------------------------
+ Tue Oct 26 03:55:08 2004
+ Tue Oct 26 04:55:08 2004
+ Tue Oct 26 05:55:08 2004
+ Tue Oct 26 08:55:08 2004
+ Wed Oct 27 09:55:08 2004
+ Wed Oct 27 10:55:08 2004
+ infinity
+(7 rows)
+
+SELECT * FROM test_timestamp WHERE i<'infinity'::timestamptz ORDER BY i;
+            i             
+--------------------------
+ -infinity
+ Tue Oct 26 03:55:08 2004
+ Tue Oct 26 04:55:08 2004
+ Tue Oct 26 05:55:08 2004
+ Tue Oct 26 08:55:08 2004
+ Wed Oct 27 09:55:08 2004
+ Wed Oct 27 10:55:08 2004
+(7 rows)
+
+SELECT * FROM test_timestamp WHERE i<='infinity'::timestamptz ORDER BY i;
+            i             
+--------------------------
+ -infinity
+ Tue Oct 26 03:55:08 2004
+ Tue Oct 26 04:55:08 2004
+ Tue Oct 26 05:55:08 2004
+ Tue Oct 26 08:55:08 2004
+ Wed Oct 27 09:55:08 2004
+ Wed Oct 27 10:55:08 2004
+ infinity
+(8 rows)
+
+SELECT * FROM test_timestamp WHERE i='infinity'::timestamptz ORDER BY i;
+    i     
+----------
+ infinity
+(1 row)
+
+SELECT * FROM test_timestamp WHERE i>='infinity'::timestamptz ORDER BY i;
+    i     
+----------
+ infinity
+(1 row)
+
+SELECT * FROM test_timestamp WHERE i>'infinity'::timestamptz ORDER BY i;
+ i 
+---
+(0 rows)
+
+-- This PST timestamptz will underflow if converted to timestamp
+SELECT * FROM test_timestamp WHERE i<='4714-11-23 17:00 BC'::timestamptz ORDER BY i;
+     i     
+-----------
+ -infinity
+(1 row)
+
+SELECT * FROM test_timestamp WHERE i>'4714-11-23 17:00 BC'::timestamptz ORDER BY i;
+            i             
+--------------------------
+ Tue Oct 26 03:55:08 2004
+ Tue Oct 26 04:55:08 2004
+ Tue Oct 26 05:55:08 2004
+ Tue Oct 26 08:55:08 2004
+ Wed Oct 27 09:55:08 2004
+ Wed Oct 27 10:55:08 2004
+ infinity
+(7 rows)
+
diff --git a/contrib/btree_gin/expected/timestamptz.out b/contrib/btree_gin/expected/timestamptz.out
index d53963d2a04b8..0dada0b662cbb 100644
--- a/contrib/btree_gin/expected/timestamptz.out
+++ b/contrib/btree_gin/expected/timestamptz.out
@@ -7,8 +7,8 @@ INSERT INTO test_timestamptz VALUES
 	( '2004-10-26 04:55:08' ),
 	( '2004-10-26 05:55:08' ),
 	( '2004-10-26 08:55:08' ),
-	( '2004-10-26 09:55:08' ),
-	( '2004-10-26 10:55:08' )
+	( '2004-10-27 09:55:08' ),
+	( '2004-10-27 10:55:08' )
 ;
 CREATE INDEX idx_timestamptz ON test_timestamptz USING gin (i);
 SELECT * FROM test_timestamptz WHERE i<'2004-10-26 08:55:08'::timestamptz ORDER BY i;
@@ -38,14 +38,113 @@ SELECT * FROM test_timestamptz WHERE i>='2004-10-26 08:55:08'::timestamptz ORDER
               i               
 ------------------------------
  Tue Oct 26 08:55:08 2004 PDT
- Tue Oct 26 09:55:08 2004 PDT
- Tue Oct 26 10:55:08 2004 PDT
+ Wed Oct 27 09:55:08 2004 PDT
+ Wed Oct 27 10:55:08 2004 PDT
 (3 rows)
 
 SELECT * FROM test_timestamptz WHERE i>'2004-10-26 08:55:08'::timestamptz ORDER BY i;
               i               
 ------------------------------
- Tue Oct 26 09:55:08 2004 PDT
- Tue Oct 26 10:55:08 2004 PDT
+ Wed Oct 27 09:55:08 2004 PDT
+ Wed Oct 27 10:55:08 2004 PDT
+(2 rows)
+
+explain (costs off)
+SELECT * FROM test_timestamptz WHERE i<'2004-10-27'::date ORDER BY i;
+                     QUERY PLAN                     
+----------------------------------------------------
+ Sort
+   Sort Key: i
+   ->  Bitmap Heap Scan on test_timestamptz
+         Recheck Cond: (i < '10-27-2004'::date)
+         ->  Bitmap Index Scan on idx_timestamptz
+               Index Cond: (i < '10-27-2004'::date)
+(6 rows)
+
+SELECT * FROM test_timestamptz WHERE i<'2004-10-27'::date ORDER BY i;
+              i               
+------------------------------
+ Tue Oct 26 03:55:08 2004 PDT
+ Tue Oct 26 04:55:08 2004 PDT
+ Tue Oct 26 05:55:08 2004 PDT
+ Tue Oct 26 08:55:08 2004 PDT
+(4 rows)
+
+SELECT * FROM test_timestamptz WHERE i<='2004-10-27'::date ORDER BY i;
+              i               
+------------------------------
+ Tue Oct 26 03:55:08 2004 PDT
+ Tue Oct 26 04:55:08 2004 PDT
+ Tue Oct 26 05:55:08 2004 PDT
+ Tue Oct 26 08:55:08 2004 PDT
+(4 rows)
+
+SELECT * FROM test_timestamptz WHERE i='2004-10-27'::date ORDER BY i;
+ i 
+---
+(0 rows)
+
+SELECT * FROM test_timestamptz WHERE i>='2004-10-27'::date ORDER BY i;
+              i               
+------------------------------
+ Wed Oct 27 09:55:08 2004 PDT
+ Wed Oct 27 10:55:08 2004 PDT
+(2 rows)
+
+SELECT * FROM test_timestamptz WHERE i>'2004-10-27'::date ORDER BY i;
+              i               
+------------------------------
+ Wed Oct 27 09:55:08 2004 PDT
+ Wed Oct 27 10:55:08 2004 PDT
+(2 rows)
+
+explain (costs off)
+SELECT * FROM test_timestamptz WHERE i<'2004-10-26 08:55:08'::timestamp ORDER BY i;
+                                       QUERY PLAN                                        
+-----------------------------------------------------------------------------------------
+ Sort
+   Sort Key: i
+   ->  Bitmap Heap Scan on test_timestamptz
+         Recheck Cond: (i < 'Tue Oct 26 08:55:08 2004'::timestamp without time zone)
+         ->  Bitmap Index Scan on idx_timestamptz
+               Index Cond: (i < 'Tue Oct 26 08:55:08 2004'::timestamp without time zone)
+(6 rows)
+
+SELECT * FROM test_timestamptz WHERE i<'2004-10-26 08:55:08'::timestamp ORDER BY i;
+              i               
+------------------------------
+ Tue Oct 26 03:55:08 2004 PDT
+ Tue Oct 26 04:55:08 2004 PDT
+ Tue Oct 26 05:55:08 2004 PDT
+(3 rows)
+
+SELECT * FROM test_timestamptz WHERE i<='2004-10-26 08:55:08'::timestamp ORDER BY i;
+              i               
+------------------------------
+ Tue Oct 26 03:55:08 2004 PDT
+ Tue Oct 26 04:55:08 2004 PDT
+ Tue Oct 26 05:55:08 2004 PDT
+ Tue Oct 26 08:55:08 2004 PDT
+(4 rows)
+
+SELECT * FROM test_timestamptz WHERE i='2004-10-26 08:55:08'::timestamp ORDER BY i;
+              i               
+------------------------------
+ Tue Oct 26 08:55:08 2004 PDT
+(1 row)
+
+SELECT * FROM test_timestamptz WHERE i>='2004-10-26 08:55:08'::timestamp ORDER BY i;
+              i               
+------------------------------
+ Tue Oct 26 08:55:08 2004 PDT
+ Wed Oct 27 09:55:08 2004 PDT
+ Wed Oct 27 10:55:08 2004 PDT
+(3 rows)
+
+SELECT * FROM test_timestamptz WHERE i>'2004-10-26 08:55:08'::timestamp ORDER BY i;
+              i               
+------------------------------
+ Wed Oct 27 09:55:08 2004 PDT
+ Wed Oct 27 10:55:08 2004 PDT
 (2 rows)
 
diff --git a/contrib/btree_gin/meson.build b/contrib/btree_gin/meson.build
index b2749f6e66951..ece0a716973ce 100644
--- a/contrib/btree_gin/meson.build
+++ b/contrib/btree_gin/meson.build
@@ -22,6 +22,7 @@ install_data(
   'btree_gin--1.0--1.1.sql',
   'btree_gin--1.1--1.2.sql',
   'btree_gin--1.2--1.3.sql',
+  'btree_gin--1.3--1.4.sql',
   kwargs: contrib_data_args,
 )
 
diff --git a/contrib/btree_gin/sql/date.sql b/contrib/btree_gin/sql/date.sql
index 35086f6b81b9b..006f6f528b835 100644
--- a/contrib/btree_gin/sql/date.sql
+++ b/contrib/btree_gin/sql/date.sql
@@ -20,3 +20,67 @@ SELECT * FROM test_date WHERE i<='2004-10-26'::date ORDER BY i;
 SELECT * FROM test_date WHERE i='2004-10-26'::date ORDER BY i;
 SELECT * FROM test_date WHERE i>='2004-10-26'::date ORDER BY i;
 SELECT * FROM test_date WHERE i>'2004-10-26'::date ORDER BY i;
+
+explain (costs off)
+SELECT * FROM test_date WHERE i<'2004-10-26'::timestamp ORDER BY i;
+
+SELECT * FROM test_date WHERE i<'2004-10-26'::timestamp ORDER BY i;
+SELECT * FROM test_date WHERE i<='2004-10-26'::timestamp ORDER BY i;
+SELECT * FROM test_date WHERE i='2004-10-26'::timestamp ORDER BY i;
+SELECT * FROM test_date WHERE i>='2004-10-26'::timestamp ORDER BY i;
+SELECT * FROM test_date WHERE i>'2004-10-26'::timestamp ORDER BY i;
+
+explain (costs off)
+SELECT * FROM test_date WHERE i<'2004-10-26'::timestamptz ORDER BY i;
+
+SELECT * FROM test_date WHERE i<'2004-10-26'::timestamptz ORDER BY i;
+SELECT * FROM test_date WHERE i<='2004-10-26'::timestamptz ORDER BY i;
+SELECT * FROM test_date WHERE i='2004-10-26'::timestamptz ORDER BY i;
+SELECT * FROM test_date WHERE i>='2004-10-26'::timestamptz ORDER BY i;
+SELECT * FROM test_date WHERE i>'2004-10-26'::timestamptz ORDER BY i;
+
+-- Check endpoint and out-of-range cases
+
+INSERT INTO test_date VALUES ('-infinity'), ('infinity');
+SELECT gin_clean_pending_list('idx_date');
+
+SELECT * FROM test_date WHERE i<'-infinity'::timestamp ORDER BY i;
+SELECT * FROM test_date WHERE i<='-infinity'::timestamp ORDER BY i;
+SELECT * FROM test_date WHERE i='-infinity'::timestamp ORDER BY i;
+SELECT * FROM test_date WHERE i>='-infinity'::timestamp ORDER BY i;
+SELECT * FROM test_date WHERE i>'-infinity'::timestamp ORDER BY i;
+
+SELECT * FROM test_date WHERE i<'infinity'::timestamp ORDER BY i;
+SELECT * FROM test_date WHERE i<='infinity'::timestamp ORDER BY i;
+SELECT * FROM test_date WHERE i='infinity'::timestamp ORDER BY i;
+SELECT * FROM test_date WHERE i>='infinity'::timestamp ORDER BY i;
+SELECT * FROM test_date WHERE i>'infinity'::timestamp ORDER BY i;
+
+SELECT * FROM test_date WHERE i<'-infinity'::timestamptz ORDER BY i;
+SELECT * FROM test_date WHERE i<='-infinity'::timestamptz ORDER BY i;
+SELECT * FROM test_date WHERE i='-infinity'::timestamptz ORDER BY i;
+SELECT * FROM test_date WHERE i>='-infinity'::timestamptz ORDER BY i;
+SELECT * FROM test_date WHERE i>'-infinity'::timestamptz ORDER BY i;
+
+SELECT * FROM test_date WHERE i<'infinity'::timestamptz ORDER BY i;
+SELECT * FROM test_date WHERE i<='infinity'::timestamptz ORDER BY i;
+SELECT * FROM test_date WHERE i='infinity'::timestamptz ORDER BY i;
+SELECT * FROM test_date WHERE i>='infinity'::timestamptz ORDER BY i;
+SELECT * FROM test_date WHERE i>'infinity'::timestamptz ORDER BY i;
+
+-- Check rounding cases
+-- '2004-10-25 00:00:01' rounds to '2004-10-25' for date.
+-- '2004-10-25 23:59:59' also rounds to '2004-10-25',
+-- so it's the same case as '2004-10-25 00:00:01'
+
+SELECT * FROM test_date WHERE i < '2004-10-25 00:00:01'::timestamp ORDER BY i;
+SELECT * FROM test_date WHERE i <= '2004-10-25 00:00:01'::timestamp ORDER BY i;
+SELECT * FROM test_date WHERE i = '2004-10-25 00:00:01'::timestamp ORDER BY i;
+SELECT * FROM test_date WHERE i > '2004-10-25 00:00:01'::timestamp ORDER BY i;
+SELECT * FROM test_date WHERE i >= '2004-10-25 00:00:01'::timestamp ORDER BY i;
+
+SELECT * FROM test_date WHERE i < '2004-10-25 00:00:01'::timestamptz ORDER BY i;
+SELECT * FROM test_date WHERE i <= '2004-10-25 00:00:01'::timestamptz ORDER BY i;
+SELECT * FROM test_date WHERE i = '2004-10-25 00:00:01'::timestamptz ORDER BY i;
+SELECT * FROM test_date WHERE i > '2004-10-25 00:00:01'::timestamptz ORDER BY i;
+SELECT * FROM test_date WHERE i >= '2004-10-25 00:00:01'::timestamptz ORDER BY i;
diff --git a/contrib/btree_gin/sql/float4.sql b/contrib/btree_gin/sql/float4.sql
index 759778ad3c3b4..0707ed6518fa2 100644
--- a/contrib/btree_gin/sql/float4.sql
+++ b/contrib/btree_gin/sql/float4.sql
@@ -13,3 +13,56 @@ SELECT * FROM test_float4 WHERE i<=1::float4 ORDER BY i;
 SELECT * FROM test_float4 WHERE i=1::float4 ORDER BY i;
 SELECT * FROM test_float4 WHERE i>=1::float4 ORDER BY i;
 SELECT * FROM test_float4 WHERE i>1::float4 ORDER BY i;
+
+explain (costs off)
+SELECT * FROM test_float4 WHERE i<1::float8 ORDER BY i;
+
+SELECT * FROM test_float4 WHERE i<1::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i<=1::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i=1::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i>=1::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i>1::float8 ORDER BY i;
+
+-- Check endpoint and out-of-range cases
+
+INSERT INTO test_float4 VALUES ('NaN'), ('Inf'), ('-Inf');
+SELECT gin_clean_pending_list('idx_float4');
+
+SELECT * FROM test_float4 WHERE i<'-Inf'::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i<='-Inf'::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i='-Inf'::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i>='-Inf'::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i>'-Inf'::float8 ORDER BY i;
+
+SELECT * FROM test_float4 WHERE i<'Inf'::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i<='Inf'::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i='Inf'::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i>='Inf'::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i>'Inf'::float8 ORDER BY i;
+
+SELECT * FROM test_float4 WHERE i<'1e300'::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i<='1e300'::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i='1e300'::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i>='1e300'::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i>'1e300'::float8 ORDER BY i;
+
+SELECT * FROM test_float4 WHERE i<'NaN'::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i<='NaN'::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i='NaN'::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i>='NaN'::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i>'NaN'::float8 ORDER BY i;
+
+-- Check rounding cases
+-- 1e-300 rounds to 0 for float4 but not for float8
+
+SELECT * FROM test_float4 WHERE i < -1e-300::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i <= -1e-300::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i = -1e-300::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i > -1e-300::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i >= -1e-300::float8 ORDER BY i;
+
+SELECT * FROM test_float4 WHERE i < 1e-300::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i <= 1e-300::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i = 1e-300::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i > 1e-300::float8 ORDER BY i;
+SELECT * FROM test_float4 WHERE i >= 1e-300::float8 ORDER BY i;
diff --git a/contrib/btree_gin/sql/float8.sql b/contrib/btree_gin/sql/float8.sql
index b046ac4e6c4bb..5f393147082b1 100644
--- a/contrib/btree_gin/sql/float8.sql
+++ b/contrib/btree_gin/sql/float8.sql
@@ -13,3 +13,12 @@ SELECT * FROM test_float8 WHERE i<=1::float8 ORDER BY i;
 SELECT * FROM test_float8 WHERE i=1::float8 ORDER BY i;
 SELECT * FROM test_float8 WHERE i>=1::float8 ORDER BY i;
 SELECT * FROM test_float8 WHERE i>1::float8 ORDER BY i;
+
+explain (costs off)
+SELECT * FROM test_float8 WHERE i<1::float4 ORDER BY i;
+
+SELECT * FROM test_float8 WHERE i<1::float4 ORDER BY i;
+SELECT * FROM test_float8 WHERE i<=1::float4 ORDER BY i;
+SELECT * FROM test_float8 WHERE i=1::float4 ORDER BY i;
+SELECT * FROM test_float8 WHERE i>=1::float4 ORDER BY i;
+SELECT * FROM test_float8 WHERE i>1::float4 ORDER BY i;
diff --git a/contrib/btree_gin/sql/int2.sql b/contrib/btree_gin/sql/int2.sql
index f06f11702f54e..959e0f6cfde01 100644
--- a/contrib/btree_gin/sql/int2.sql
+++ b/contrib/btree_gin/sql/int2.sql
@@ -13,3 +13,38 @@ SELECT * FROM test_int2 WHERE i<=1::int2 ORDER BY i;
 SELECT * FROM test_int2 WHERE i=1::int2 ORDER BY i;
 SELECT * FROM test_int2 WHERE i>=1::int2 ORDER BY i;
 SELECT * FROM test_int2 WHERE i>1::int2 ORDER BY i;
+
+explain (costs off)
+SELECT * FROM test_int2 WHERE i<1::int4 ORDER BY i;
+
+SELECT * FROM test_int2 WHERE i<1::int4 ORDER BY i;
+SELECT * FROM test_int2 WHERE i<=1::int4 ORDER BY i;
+SELECT * FROM test_int2 WHERE i=1::int4 ORDER BY i;
+SELECT * FROM test_int2 WHERE i>=1::int4 ORDER BY i;
+SELECT * FROM test_int2 WHERE i>1::int4 ORDER BY i;
+
+explain (costs off)
+SELECT * FROM test_int2 WHERE i<1::int8 ORDER BY i;
+
+SELECT * FROM test_int2 WHERE i<1::int8 ORDER BY i;
+SELECT * FROM test_int2 WHERE i<=1::int8 ORDER BY i;
+SELECT * FROM test_int2 WHERE i=1::int8 ORDER BY i;
+SELECT * FROM test_int2 WHERE i>=1::int8 ORDER BY i;
+SELECT * FROM test_int2 WHERE i>1::int8 ORDER BY i;
+
+-- Check endpoint and out-of-range cases
+
+INSERT INTO test_int2 VALUES ((-32768)::int2),(32767);
+SELECT gin_clean_pending_list('idx_int2');
+
+SELECT * FROM test_int2 WHERE i<(-32769)::int4 ORDER BY i;
+SELECT * FROM test_int2 WHERE i<=(-32769)::int4 ORDER BY i;
+SELECT * FROM test_int2 WHERE i=(-32769)::int4 ORDER BY i;
+SELECT * FROM test_int2 WHERE i>=(-32769)::int4 ORDER BY i;
+SELECT * FROM test_int2 WHERE i>(-32769)::int4 ORDER BY i;
+
+SELECT * FROM test_int2 WHERE i<32768::int4 ORDER BY i;
+SELECT * FROM test_int2 WHERE i<=32768::int4 ORDER BY i;
+SELECT * FROM test_int2 WHERE i=32768::int4 ORDER BY i;
+SELECT * FROM test_int2 WHERE i>=32768::int4 ORDER BY i;
+SELECT * FROM test_int2 WHERE i>32768::int4 ORDER BY i;
diff --git a/contrib/btree_gin/sql/int4.sql b/contrib/btree_gin/sql/int4.sql
index 6499c29630722..9a45530b63ad7 100644
--- a/contrib/btree_gin/sql/int4.sql
+++ b/contrib/btree_gin/sql/int4.sql
@@ -13,3 +13,21 @@ SELECT * FROM test_int4 WHERE i<=1::int4 ORDER BY i;
 SELECT * FROM test_int4 WHERE i=1::int4 ORDER BY i;
 SELECT * FROM test_int4 WHERE i>=1::int4 ORDER BY i;
 SELECT * FROM test_int4 WHERE i>1::int4 ORDER BY i;
+
+explain (costs off)
+SELECT * FROM test_int4 WHERE i<1::int2 ORDER BY i;
+
+SELECT * FROM test_int4 WHERE i<1::int2 ORDER BY i;
+SELECT * FROM test_int4 WHERE i<=1::int2 ORDER BY i;
+SELECT * FROM test_int4 WHERE i=1::int2 ORDER BY i;
+SELECT * FROM test_int4 WHERE i>=1::int2 ORDER BY i;
+SELECT * FROM test_int4 WHERE i>1::int2 ORDER BY i;
+
+explain (costs off)
+SELECT * FROM test_int4 WHERE i<1::int8 ORDER BY i;
+
+SELECT * FROM test_int4 WHERE i<1::int8 ORDER BY i;
+SELECT * FROM test_int4 WHERE i<=1::int8 ORDER BY i;
+SELECT * FROM test_int4 WHERE i=1::int8 ORDER BY i;
+SELECT * FROM test_int4 WHERE i>=1::int8 ORDER BY i;
+SELECT * FROM test_int4 WHERE i>1::int8 ORDER BY i;
diff --git a/contrib/btree_gin/sql/int8.sql b/contrib/btree_gin/sql/int8.sql
index 4d9c2871814c4..b31f27c69b90a 100644
--- a/contrib/btree_gin/sql/int8.sql
+++ b/contrib/btree_gin/sql/int8.sql
@@ -13,3 +13,21 @@ SELECT * FROM test_int8 WHERE i<=1::int8 ORDER BY i;
 SELECT * FROM test_int8 WHERE i=1::int8 ORDER BY i;
 SELECT * FROM test_int8 WHERE i>=1::int8 ORDER BY i;
 SELECT * FROM test_int8 WHERE i>1::int8 ORDER BY i;
+
+explain (costs off)
+SELECT * FROM test_int8 WHERE i<1::int2 ORDER BY i;
+
+SELECT * FROM test_int8 WHERE i<1::int2 ORDER BY i;
+SELECT * FROM test_int8 WHERE i<=1::int2 ORDER BY i;
+SELECT * FROM test_int8 WHERE i=1::int2 ORDER BY i;
+SELECT * FROM test_int8 WHERE i>=1::int2 ORDER BY i;
+SELECT * FROM test_int8 WHERE i>1::int2 ORDER BY i;
+
+explain (costs off)
+SELECT * FROM test_int8 WHERE i<1::int4 ORDER BY i;
+
+SELECT * FROM test_int8 WHERE i<1::int4 ORDER BY i;
+SELECT * FROM test_int8 WHERE i<=1::int4 ORDER BY i;
+SELECT * FROM test_int8 WHERE i=1::int4 ORDER BY i;
+SELECT * FROM test_int8 WHERE i>=1::int4 ORDER BY i;
+SELECT * FROM test_int8 WHERE i>1::int4 ORDER BY i;
diff --git a/contrib/btree_gin/sql/name.sql b/contrib/btree_gin/sql/name.sql
index c11580cdf9609..551d928940746 100644
--- a/contrib/btree_gin/sql/name.sql
+++ b/contrib/btree_gin/sql/name.sql
@@ -19,3 +19,14 @@ EXPLAIN (COSTS OFF) SELECT * FROM test_name WHERE i<='abc' ORDER BY i;
 EXPLAIN (COSTS OFF) SELECT * FROM test_name WHERE i='abc' ORDER BY i;
 EXPLAIN (COSTS OFF) SELECT * FROM test_name WHERE i>='abc' ORDER BY i;
 EXPLAIN (COSTS OFF) SELECT * FROM test_name WHERE i>'abc' ORDER BY i;
+
+explain (costs off)
+SELECT * FROM test_name WHERE i<'abc'::text ORDER BY i;
+
+SELECT * FROM test_name WHERE i<'abc'::text ORDER BY i;
+SELECT * FROM test_name WHERE i<='abc'::text ORDER BY i;
+SELECT * FROM test_name WHERE i='abc'::text ORDER BY i;
+SELECT * FROM test_name WHERE i>='abc'::text ORDER BY i;
+SELECT * FROM test_name WHERE i>'abc'::text ORDER BY i;
+
+SELECT * FROM test_name WHERE i<=repeat('abc', 100) ORDER BY i;
diff --git a/contrib/btree_gin/sql/text.sql b/contrib/btree_gin/sql/text.sql
index d5b3b39898988..978b21376fd85 100644
--- a/contrib/btree_gin/sql/text.sql
+++ b/contrib/btree_gin/sql/text.sql
@@ -13,3 +13,12 @@ SELECT * FROM test_text WHERE i<='abc' ORDER BY i;
 SELECT * FROM test_text WHERE i='abc' ORDER BY i;
 SELECT * FROM test_text WHERE i>='abc' ORDER BY i;
 SELECT * FROM test_text WHERE i>'abc' ORDER BY i;
+
+explain (costs off)
+SELECT * FROM test_text WHERE i<'abc'::name COLLATE "default" ORDER BY i;
+
+SELECT * FROM test_text WHERE i<'abc'::name COLLATE "default" ORDER BY i;
+SELECT * FROM test_text WHERE i<='abc'::name COLLATE "default" ORDER BY i;
+SELECT * FROM test_text WHERE i='abc'::name COLLATE "default" ORDER BY i;
+SELECT * FROM test_text WHERE i>='abc'::name COLLATE "default" ORDER BY i;
+SELECT * FROM test_text WHERE i>'abc'::name COLLATE "default" ORDER BY i;
diff --git a/contrib/btree_gin/sql/timestamp.sql b/contrib/btree_gin/sql/timestamp.sql
index 56727e81c4aff..1ee4edb5ea4d2 100644
--- a/contrib/btree_gin/sql/timestamp.sql
+++ b/contrib/btree_gin/sql/timestamp.sql
@@ -9,8 +9,8 @@ INSERT INTO test_timestamp VALUES
 	( '2004-10-26 04:55:08' ),
 	( '2004-10-26 05:55:08' ),
 	( '2004-10-26 08:55:08' ),
-	( '2004-10-26 09:55:08' ),
-	( '2004-10-26 10:55:08' )
+	( '2004-10-27 09:55:08' ),
+	( '2004-10-27 10:55:08' )
 ;
 
 CREATE INDEX idx_timestamp ON test_timestamp USING gin (i);
@@ -20,3 +20,54 @@ SELECT * FROM test_timestamp WHERE i<='2004-10-26 08:55:08'::timestamp ORDER BY
 SELECT * FROM test_timestamp WHERE i='2004-10-26 08:55:08'::timestamp ORDER BY i;
 SELECT * FROM test_timestamp WHERE i>='2004-10-26 08:55:08'::timestamp ORDER BY i;
 SELECT * FROM test_timestamp WHERE i>'2004-10-26 08:55:08'::timestamp ORDER BY i;
+
+explain (costs off)
+SELECT * FROM test_timestamp WHERE i<'2004-10-27'::date ORDER BY i;
+
+SELECT * FROM test_timestamp WHERE i<'2004-10-27'::date ORDER BY i;
+SELECT * FROM test_timestamp WHERE i<='2004-10-27'::date ORDER BY i;
+SELECT * FROM test_timestamp WHERE i='2004-10-27'::date ORDER BY i;
+SELECT * FROM test_timestamp WHERE i>='2004-10-27'::date ORDER BY i;
+SELECT * FROM test_timestamp WHERE i>'2004-10-27'::date ORDER BY i;
+
+explain (costs off)
+SELECT * FROM test_timestamp WHERE i<'2004-10-26 08:55:08'::timestamptz ORDER BY i;
+
+SELECT * FROM test_timestamp WHERE i<'2004-10-26 08:55:08'::timestamptz ORDER BY i;
+SELECT * FROM test_timestamp WHERE i<='2004-10-26 08:55:08'::timestamptz ORDER BY i;
+SELECT * FROM test_timestamp WHERE i='2004-10-26 08:55:08'::timestamptz ORDER BY i;
+SELECT * FROM test_timestamp WHERE i>='2004-10-26 08:55:08'::timestamptz ORDER BY i;
+SELECT * FROM test_timestamp WHERE i>'2004-10-26 08:55:08'::timestamptz ORDER BY i;
+
+-- Check endpoint and out-of-range cases
+
+INSERT INTO test_timestamp VALUES ('-infinity'), ('infinity');
+SELECT gin_clean_pending_list('idx_timestamp');
+
+SELECT * FROM test_timestamp WHERE i<'-infinity'::date ORDER BY i;
+SELECT * FROM test_timestamp WHERE i<='-infinity'::date ORDER BY i;
+SELECT * FROM test_timestamp WHERE i='-infinity'::date ORDER BY i;
+SELECT * FROM test_timestamp WHERE i>='-infinity'::date ORDER BY i;
+SELECT * FROM test_timestamp WHERE i>'-infinity'::date ORDER BY i;
+
+SELECT * FROM test_timestamp WHERE i<'infinity'::date ORDER BY i;
+SELECT * FROM test_timestamp WHERE i<='infinity'::date ORDER BY i;
+SELECT * FROM test_timestamp WHERE i='infinity'::date ORDER BY i;
+SELECT * FROM test_timestamp WHERE i>='infinity'::date ORDER BY i;
+SELECT * FROM test_timestamp WHERE i>'infinity'::date ORDER BY i;
+
+SELECT * FROM test_timestamp WHERE i<'-infinity'::timestamptz ORDER BY i;
+SELECT * FROM test_timestamp WHERE i<='-infinity'::timestamptz ORDER BY i;
+SELECT * FROM test_timestamp WHERE i='-infinity'::timestamptz ORDER BY i;
+SELECT * FROM test_timestamp WHERE i>='-infinity'::timestamptz ORDER BY i;
+SELECT * FROM test_timestamp WHERE i>'-infinity'::timestamptz ORDER BY i;
+
+SELECT * FROM test_timestamp WHERE i<'infinity'::timestamptz ORDER BY i;
+SELECT * FROM test_timestamp WHERE i<='infinity'::timestamptz ORDER BY i;
+SELECT * FROM test_timestamp WHERE i='infinity'::timestamptz ORDER BY i;
+SELECT * FROM test_timestamp WHERE i>='infinity'::timestamptz ORDER BY i;
+SELECT * FROM test_timestamp WHERE i>'infinity'::timestamptz ORDER BY i;
+
+-- This PST timestamptz will underflow if converted to timestamp
+SELECT * FROM test_timestamp WHERE i<='4714-11-23 17:00 BC'::timestamptz ORDER BY i;
+SELECT * FROM test_timestamp WHERE i>'4714-11-23 17:00 BC'::timestamptz ORDER BY i;
diff --git a/contrib/btree_gin/sql/timestamptz.sql b/contrib/btree_gin/sql/timestamptz.sql
index e6cfdb1b07447..40d2d7ed329d2 100644
--- a/contrib/btree_gin/sql/timestamptz.sql
+++ b/contrib/btree_gin/sql/timestamptz.sql
@@ -9,8 +9,8 @@ INSERT INTO test_timestamptz VALUES
 	( '2004-10-26 04:55:08' ),
 	( '2004-10-26 05:55:08' ),
 	( '2004-10-26 08:55:08' ),
-	( '2004-10-26 09:55:08' ),
-	( '2004-10-26 10:55:08' )
+	( '2004-10-27 09:55:08' ),
+	( '2004-10-27 10:55:08' )
 ;
 
 CREATE INDEX idx_timestamptz ON test_timestamptz USING gin (i);
@@ -20,3 +20,21 @@ SELECT * FROM test_timestamptz WHERE i<='2004-10-26 08:55:08'::timestamptz ORDER
 SELECT * FROM test_timestamptz WHERE i='2004-10-26 08:55:08'::timestamptz ORDER BY i;
 SELECT * FROM test_timestamptz WHERE i>='2004-10-26 08:55:08'::timestamptz ORDER BY i;
 SELECT * FROM test_timestamptz WHERE i>'2004-10-26 08:55:08'::timestamptz ORDER BY i;
+
+explain (costs off)
+SELECT * FROM test_timestamptz WHERE i<'2004-10-27'::date ORDER BY i;
+
+SELECT * FROM test_timestamptz WHERE i<'2004-10-27'::date ORDER BY i;
+SELECT * FROM test_timestamptz WHERE i<='2004-10-27'::date ORDER BY i;
+SELECT * FROM test_timestamptz WHERE i='2004-10-27'::date ORDER BY i;
+SELECT * FROM test_timestamptz WHERE i>='2004-10-27'::date ORDER BY i;
+SELECT * FROM test_timestamptz WHERE i>'2004-10-27'::date ORDER BY i;
+
+explain (costs off)
+SELECT * FROM test_timestamptz WHERE i<'2004-10-26 08:55:08'::timestamp ORDER BY i;
+
+SELECT * FROM test_timestamptz WHERE i<'2004-10-26 08:55:08'::timestamp ORDER BY i;
+SELECT * FROM test_timestamptz WHERE i<='2004-10-26 08:55:08'::timestamp ORDER BY i;
+SELECT * FROM test_timestamptz WHERE i='2004-10-26 08:55:08'::timestamp ORDER BY i;
+SELECT * FROM test_timestamptz WHERE i>='2004-10-26 08:55:08'::timestamp ORDER BY i;
+SELECT * FROM test_timestamptz WHERE i>'2004-10-26 08:55:08'::timestamp ORDER BY i;
diff --git a/contrib/btree_gist/Makefile b/contrib/btree_gist/Makefile
index 68190ac5e4687..7ac2df26c1044 100644
--- a/contrib/btree_gist/Makefile
+++ b/contrib/btree_gist/Makefile
@@ -34,7 +34,7 @@ DATA = btree_gist--1.0--1.1.sql \
        btree_gist--1.1--1.2.sql btree_gist--1.2.sql btree_gist--1.2--1.3.sql \
        btree_gist--1.3--1.4.sql btree_gist--1.4--1.5.sql \
        btree_gist--1.5--1.6.sql btree_gist--1.6--1.7.sql \
-       btree_gist--1.7--1.8.sql btree_gist--1.8--1.9.sql
+       btree_gist--1.7--1.8.sql
 PGFILEDESC = "btree_gist - B-tree equivalent GiST operator classes"
 
 REGRESS = init int2 int4 int8 float4 float8 cash oid timestamp timestamptz \
diff --git a/contrib/btree_gist/btree_gist--1.7--1.8.sql b/contrib/btree_gist/btree_gist--1.7--1.8.sql
index 8f79365a461f8..22316dc3f566c 100644
--- a/contrib/btree_gist/btree_gist--1.7--1.8.sql
+++ b/contrib/btree_gist/btree_gist--1.7--1.8.sql
@@ -3,6 +3,203 @@
 -- complain if script is sourced in psql, rather than via CREATE EXTENSION
 \echo Use "ALTER EXTENSION btree_gist UPDATE TO '1.8'" to load this file. \quit
 
+-- Add sortsupport functions
+
+CREATE FUNCTION gbt_bit_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_varbit_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_bool_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_bytea_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_cash_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_date_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_enum_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_float4_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_float8_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_inet_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_int2_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_int4_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_int8_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_intv_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_macaddr_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_macad8_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_numeric_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_oid_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_text_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_bpchar_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_time_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_ts_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+CREATE FUNCTION gbt_uuid_sortsupport(internal)
+RETURNS void
+AS 'MODULE_PATHNAME'
+LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
+
+ALTER OPERATOR FAMILY gist_bit_ops USING gist ADD
+	FUNCTION	11  (bit, bit) gbt_bit_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_vbit_ops USING gist ADD
+	FUNCTION	11  (varbit, varbit) gbt_varbit_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_bool_ops USING gist ADD
+	FUNCTION	11  (bool, bool) gbt_bool_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_bytea_ops USING gist ADD
+	FUNCTION	11  (bytea, bytea) gbt_bytea_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_cash_ops USING gist ADD
+	FUNCTION	11  (money, money) gbt_cash_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_date_ops USING gist ADD
+	FUNCTION	11  (date, date) gbt_date_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_enum_ops USING gist ADD
+	FUNCTION	11  (anyenum, anyenum) gbt_enum_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_float4_ops USING gist ADD
+	FUNCTION	11  (float4, float4) gbt_float4_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_float8_ops USING gist ADD
+	FUNCTION	11  (float8, float8) gbt_float8_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_inet_ops USING gist ADD
+	FUNCTION	11  (inet, inet) gbt_inet_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_cidr_ops USING gist ADD
+	FUNCTION	11  (cidr, cidr) gbt_inet_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_int2_ops USING gist ADD
+	FUNCTION	11  (int2, int2) gbt_int2_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_int4_ops USING gist ADD
+	FUNCTION	11  (int4, int4) gbt_int4_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_int8_ops USING gist ADD
+	FUNCTION	11  (int8, int8) gbt_int8_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_interval_ops USING gist ADD
+	FUNCTION	11  (interval, interval) gbt_intv_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_macaddr_ops USING gist ADD
+	FUNCTION	11  (macaddr, macaddr) gbt_macaddr_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_macaddr8_ops USING gist ADD
+	FUNCTION	11  (macaddr8, macaddr8) gbt_macad8_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_numeric_ops USING gist ADD
+	FUNCTION	11  (numeric, numeric) gbt_numeric_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_oid_ops USING gist ADD
+	FUNCTION	11  (oid, oid) gbt_oid_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_text_ops USING gist ADD
+	FUNCTION	11  (text, text) gbt_text_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_bpchar_ops USING gist ADD
+	FUNCTION	11  (bpchar, bpchar) gbt_bpchar_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_time_ops USING gist ADD
+	FUNCTION	11  (time, time) gbt_time_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_timetz_ops USING gist ADD
+	FUNCTION	11  (timetz, timetz) gbt_time_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_timestamp_ops USING gist ADD
+	FUNCTION	11  (timestamp, timestamp) gbt_ts_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_timestamptz_ops USING gist ADD
+	FUNCTION	11  (timestamptz, timestamptz) gbt_ts_sortsupport (internal) ;
+
+ALTER OPERATOR FAMILY gist_uuid_ops USING gist ADD
+	FUNCTION	11  (uuid, uuid) gbt_uuid_sortsupport (internal) ;
+
+-- Add translate_cmptype functions
+
 CREATE FUNCTION gist_translate_cmptype_btree(int)
 RETURNS smallint
 AS 'MODULE_PATHNAME'
diff --git a/contrib/btree_gist/btree_gist--1.8--1.9.sql b/contrib/btree_gist/btree_gist--1.8--1.9.sql
deleted file mode 100644
index 4b38749bf5f34..0000000000000
--- a/contrib/btree_gist/btree_gist--1.8--1.9.sql
+++ /dev/null
@@ -1,197 +0,0 @@
-/* contrib/btree_gist/btree_gist--1.7--1.8.sql */
-
--- complain if script is sourced in psql, rather than via CREATE EXTENSION
-\echo Use "ALTER EXTENSION btree_gist UPDATE TO '1.9'" to load this file. \quit
-
-CREATE FUNCTION gbt_bit_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_varbit_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_bool_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_bytea_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_cash_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_date_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_enum_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_float4_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_float8_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_inet_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_int2_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_int4_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_int8_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_intv_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_macaddr_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_macad8_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_numeric_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_oid_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_text_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_bpchar_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_time_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_ts_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-CREATE FUNCTION gbt_uuid_sortsupport(internal)
-RETURNS void
-AS 'MODULE_PATHNAME'
-LANGUAGE C IMMUTABLE PARALLEL SAFE STRICT;
-
-ALTER OPERATOR FAMILY gist_bit_ops USING gist ADD
-	FUNCTION	11  (bit, bit) gbt_bit_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_vbit_ops USING gist ADD
-	FUNCTION	11  (varbit, varbit) gbt_varbit_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_bool_ops USING gist ADD
-	FUNCTION	11  (bool, bool) gbt_bool_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_bytea_ops USING gist ADD
-	FUNCTION	11  (bytea, bytea) gbt_bytea_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_cash_ops USING gist ADD
-	FUNCTION	11  (money, money) gbt_cash_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_date_ops USING gist ADD
-	FUNCTION	11  (date, date) gbt_date_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_enum_ops USING gist ADD
-	FUNCTION	11  (anyenum, anyenum) gbt_enum_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_float4_ops USING gist ADD
-	FUNCTION	11  (float4, float4) gbt_float4_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_float8_ops USING gist ADD
-	FUNCTION	11  (float8, float8) gbt_float8_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_inet_ops USING gist ADD
-	FUNCTION	11  (inet, inet) gbt_inet_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_cidr_ops USING gist ADD
-	FUNCTION	11  (cidr, cidr) gbt_inet_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_int2_ops USING gist ADD
-	FUNCTION	11  (int2, int2) gbt_int2_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_int4_ops USING gist ADD
-	FUNCTION	11  (int4, int4) gbt_int4_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_int8_ops USING gist ADD
-	FUNCTION	11  (int8, int8) gbt_int8_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_interval_ops USING gist ADD
-	FUNCTION	11  (interval, interval) gbt_intv_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_macaddr_ops USING gist ADD
-	FUNCTION	11  (macaddr, macaddr) gbt_macaddr_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_macaddr8_ops USING gist ADD
-	FUNCTION	11  (macaddr8, macaddr8) gbt_macad8_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_numeric_ops USING gist ADD
-	FUNCTION	11  (numeric, numeric) gbt_numeric_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_oid_ops USING gist ADD
-	FUNCTION	11  (oid, oid) gbt_oid_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_text_ops USING gist ADD
-	FUNCTION	11  (text, text) gbt_text_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_bpchar_ops USING gist ADD
-	FUNCTION	11  (bpchar, bpchar) gbt_bpchar_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_time_ops USING gist ADD
-	FUNCTION	11  (time, time) gbt_time_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_timetz_ops USING gist ADD
-	FUNCTION	11  (timetz, timetz) gbt_time_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_timestamp_ops USING gist ADD
-	FUNCTION	11  (timestamp, timestamp) gbt_ts_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_timestamptz_ops USING gist ADD
-	FUNCTION	11  (timestamptz, timestamptz) gbt_ts_sortsupport (internal) ;
-
-ALTER OPERATOR FAMILY gist_uuid_ops USING gist ADD
-	FUNCTION	11  (uuid, uuid) gbt_uuid_sortsupport (internal) ;
diff --git a/contrib/btree_gist/btree_gist.control b/contrib/btree_gist/btree_gist.control
index 69d9341a0adea..abf66538f3244 100644
--- a/contrib/btree_gist/btree_gist.control
+++ b/contrib/btree_gist/btree_gist.control
@@ -1,6 +1,6 @@
 # btree_gist extension
 comment = 'support for indexing common datatypes in GiST'
-default_version = '1.9'
+default_version = '1.8'
 module_pathname = '$libdir/btree_gist'
 relocatable = true
 trusted = true
diff --git a/contrib/btree_gist/meson.build b/contrib/btree_gist/meson.build
index 89932dd3844ee..f4fa9574f1fd7 100644
--- a/contrib/btree_gist/meson.build
+++ b/contrib/btree_gist/meson.build
@@ -51,7 +51,6 @@ install_data(
   'btree_gist--1.5--1.6.sql',
   'btree_gist--1.6--1.7.sql',
   'btree_gist--1.7--1.8.sql',
-  'btree_gist--1.8--1.9.sql',
   kwargs: contrib_data_args,
 )
 
diff --git a/contrib/dblink/dblink.c b/contrib/dblink/dblink.c
index 8a0b112a7ff29..f98805fb5f735 100644
--- a/contrib/dblink/dblink.c
+++ b/contrib/dblink/dblink.c
@@ -101,8 +101,8 @@ static void materializeQueryResult(FunctionCallInfo fcinfo,
 								   const char *conname,
 								   const char *sql,
 								   bool fail);
-static PGresult *storeQueryResult(volatile storeInfo *sinfo, PGconn *conn, const char *sql);
-static void storeRow(volatile storeInfo *sinfo, PGresult *res, bool first);
+static PGresult *storeQueryResult(storeInfo *sinfo, PGconn *conn, const char *sql);
+static void storeRow(storeInfo *sinfo, PGresult *res, bool first);
 static remoteConn *getConnectionByName(const char *name);
 static HTAB *createConnHash(void);
 static remoteConn *createNewConnection(const char *name);
@@ -169,14 +169,6 @@ typedef struct remoteConnHashEnt
 /* initial number of connection hashes */
 #define NUMCONN 16
 
-static char *
-xpstrdup(const char *in)
-{
-	if (in == NULL)
-		return NULL;
-	return pstrdup(in);
-}
-
 pg_noreturn static void
 dblink_res_internalerror(PGconn *conn, PGresult *res, const char *p2)
 {
@@ -240,6 +232,10 @@ dblink_get_conn(char *conname_or_str,
 					 errmsg("could not establish connection"),
 					 errdetail_internal("%s", msg)));
 		}
+
+		PQsetNoticeReceiver(conn, libpqsrv_notice_receiver,
+							"received message via remote connection");
+
 		dblink_security_check(conn, NULL, connstr);
 		if (PQclientEncoding(conn) != GetDatabaseEncoding())
 			PQsetClientEncoding(conn, GetDatabaseEncodingName());
@@ -338,6 +334,9 @@ dblink_connect(PG_FUNCTION_ARGS)
 				 errdetail_internal("%s", msg)));
 	}
 
+	PQsetNoticeReceiver(conn, libpqsrv_notice_receiver,
+						"received message via remote connection");
+
 	/* check password actually used if not superuser */
 	dblink_security_check(conn, connname, connstr);
 
@@ -863,131 +862,123 @@ static void
 materializeResult(FunctionCallInfo fcinfo, PGconn *conn, PGresult *res)
 {
 	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
+	TupleDesc	tupdesc;
+	bool		is_sql_cmd;
+	int			ntuples;
+	int			nfields;
 
 	/* prepTuplestoreResult must have been called previously */
 	Assert(rsinfo->returnMode == SFRM_Materialize);
 
-	PG_TRY();
+	if (PQresultStatus(res) == PGRES_COMMAND_OK)
 	{
-		TupleDesc	tupdesc;
-		bool		is_sql_cmd;
-		int			ntuples;
-		int			nfields;
+		is_sql_cmd = true;
 
-		if (PQresultStatus(res) == PGRES_COMMAND_OK)
-		{
-			is_sql_cmd = true;
+		/*
+		 * need a tuple descriptor representing one TEXT column to return the
+		 * command status string as our result tuple
+		 */
+		tupdesc = CreateTemplateTupleDesc(1);
+		TupleDescInitEntry(tupdesc, (AttrNumber) 1, "status",
+						   TEXTOID, -1, 0);
+		ntuples = 1;
+		nfields = 1;
+	}
+	else
+	{
+		Assert(PQresultStatus(res) == PGRES_TUPLES_OK);
 
-			/*
-			 * need a tuple descriptor representing one TEXT column to return
-			 * the command status string as our result tuple
-			 */
-			tupdesc = CreateTemplateTupleDesc(1);
-			TupleDescInitEntry(tupdesc, (AttrNumber) 1, "status",
-							   TEXTOID, -1, 0);
-			ntuples = 1;
-			nfields = 1;
-		}
-		else
-		{
-			Assert(PQresultStatus(res) == PGRES_TUPLES_OK);
+		is_sql_cmd = false;
 
-			is_sql_cmd = false;
+		/* get a tuple descriptor for our result type */
+		switch (get_call_result_type(fcinfo, NULL, &tupdesc))
+		{
+			case TYPEFUNC_COMPOSITE:
+				/* success */
+				break;
+			case TYPEFUNC_RECORD:
+				/* failed to determine actual type of RECORD */
+				ereport(ERROR,
+						(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+						 errmsg("function returning record called in context "
+								"that cannot accept type record")));
+				break;
+			default:
+				/* result type isn't composite */
+				elog(ERROR, "return type must be a row type");
+				break;
+		}
 
-			/* get a tuple descriptor for our result type */
-			switch (get_call_result_type(fcinfo, NULL, &tupdesc))
-			{
-				case TYPEFUNC_COMPOSITE:
-					/* success */
-					break;
-				case TYPEFUNC_RECORD:
-					/* failed to determine actual type of RECORD */
-					ereport(ERROR,
-							(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-							 errmsg("function returning record called in context "
-									"that cannot accept type record")));
-					break;
-				default:
-					/* result type isn't composite */
-					elog(ERROR, "return type must be a row type");
-					break;
-			}
+		/* make sure we have a persistent copy of the tupdesc */
+		tupdesc = CreateTupleDescCopy(tupdesc);
+		ntuples = PQntuples(res);
+		nfields = PQnfields(res);
+	}
 
-			/* make sure we have a persistent copy of the tupdesc */
-			tupdesc = CreateTupleDescCopy(tupdesc);
-			ntuples = PQntuples(res);
-			nfields = PQnfields(res);
-		}
+	/*
+	 * check result and tuple descriptor have the same number of columns
+	 */
+	if (nfields != tupdesc->natts)
+		ereport(ERROR,
+				(errcode(ERRCODE_DATATYPE_MISMATCH),
+				 errmsg("remote query result rowtype does not match "
+						"the specified FROM clause rowtype")));
 
-		/*
-		 * check result and tuple descriptor have the same number of columns
-		 */
-		if (nfields != tupdesc->natts)
-			ereport(ERROR,
-					(errcode(ERRCODE_DATATYPE_MISMATCH),
-					 errmsg("remote query result rowtype does not match "
-							"the specified FROM clause rowtype")));
+	if (ntuples > 0)
+	{
+		AttInMetadata *attinmeta;
+		int			nestlevel = -1;
+		Tuplestorestate *tupstore;
+		MemoryContext oldcontext;
+		int			row;
+		char	  **values;
 
-		if (ntuples > 0)
-		{
-			AttInMetadata *attinmeta;
-			int			nestlevel = -1;
-			Tuplestorestate *tupstore;
-			MemoryContext oldcontext;
-			int			row;
-			char	  **values;
+		attinmeta = TupleDescGetAttInMetadata(tupdesc);
 
-			attinmeta = TupleDescGetAttInMetadata(tupdesc);
+		/* Set GUCs to ensure we read GUC-sensitive data types correctly */
+		if (!is_sql_cmd)
+			nestlevel = applyRemoteGucs(conn);
 
-			/* Set GUCs to ensure we read GUC-sensitive data types correctly */
-			if (!is_sql_cmd)
-				nestlevel = applyRemoteGucs(conn);
+		oldcontext = MemoryContextSwitchTo(rsinfo->econtext->ecxt_per_query_memory);
+		tupstore = tuplestore_begin_heap(true, false, work_mem);
+		rsinfo->setResult = tupstore;
+		rsinfo->setDesc = tupdesc;
+		MemoryContextSwitchTo(oldcontext);
 
-			oldcontext = MemoryContextSwitchTo(rsinfo->econtext->ecxt_per_query_memory);
-			tupstore = tuplestore_begin_heap(true, false, work_mem);
-			rsinfo->setResult = tupstore;
-			rsinfo->setDesc = tupdesc;
-			MemoryContextSwitchTo(oldcontext);
+		values = palloc_array(char *, nfields);
 
-			values = palloc_array(char *, nfields);
+		/* put all tuples into the tuplestore */
+		for (row = 0; row < ntuples; row++)
+		{
+			HeapTuple	tuple;
 
-			/* put all tuples into the tuplestore */
-			for (row = 0; row < ntuples; row++)
+			if (!is_sql_cmd)
 			{
-				HeapTuple	tuple;
+				int			i;
 
-				if (!is_sql_cmd)
+				for (i = 0; i < nfields; i++)
 				{
-					int			i;
-
-					for (i = 0; i < nfields; i++)
-					{
-						if (PQgetisnull(res, row, i))
-							values[i] = NULL;
-						else
-							values[i] = PQgetvalue(res, row, i);
-					}
+					if (PQgetisnull(res, row, i))
+						values[i] = NULL;
+					else
+						values[i] = PQgetvalue(res, row, i);
 				}
-				else
-				{
-					values[0] = PQcmdStatus(res);
-				}
-
-				/* build the tuple and put it into the tuplestore. */
-				tuple = BuildTupleFromCStrings(attinmeta, values);
-				tuplestore_puttuple(tupstore, tuple);
+			}
+			else
+			{
+				values[0] = PQcmdStatus(res);
 			}
 
-			/* clean up GUC settings, if we changed any */
-			restoreLocalGucs(nestlevel);
+			/* build the tuple and put it into the tuplestore. */
+			tuple = BuildTupleFromCStrings(attinmeta, values);
+			tuplestore_puttuple(tupstore, tuple);
 		}
+
+		/* clean up GUC settings, if we changed any */
+		restoreLocalGucs(nestlevel);
 	}
-	PG_FINALLY();
-	{
-		/* be sure to release the libpq result */
-		PQclear(res);
-	}
-	PG_END_TRY();
+
+	PQclear(res);
 }
 
 /*
@@ -1006,16 +997,17 @@ materializeQueryResult(FunctionCallInfo fcinfo,
 					   bool fail)
 {
 	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
-	PGresult   *volatile res = NULL;
-	volatile storeInfo sinfo = {0};
 
 	/* prepTuplestoreResult must have been called previously */
 	Assert(rsinfo->returnMode == SFRM_Materialize);
 
-	sinfo.fcinfo = fcinfo;
-
+	/* Use a PG_TRY block to ensure we pump libpq dry of results */
 	PG_TRY();
 	{
+		storeInfo	sinfo = {0};
+		PGresult   *res;
+
+		sinfo.fcinfo = fcinfo;
 		/* Create short-lived memory context for data conversions */
 		sinfo.tmpcontext = AllocSetContextCreate(CurrentMemoryContext,
 												 "dblink temporary context",
@@ -1028,14 +1020,7 @@ materializeQueryResult(FunctionCallInfo fcinfo,
 			(PQresultStatus(res) != PGRES_COMMAND_OK &&
 			 PQresultStatus(res) != PGRES_TUPLES_OK))
 		{
-			/*
-			 * dblink_res_error will clear the passed PGresult, so we need
-			 * this ugly dance to avoid doing so twice during error exit
-			 */
-			PGresult   *res1 = res;
-
-			res = NULL;
-			dblink_res_error(conn, conname, res1, fail,
+			dblink_res_error(conn, conname, res, fail,
 							 "while executing query");
 			/* if fail isn't set, we'll return an empty query result */
 		}
@@ -1074,7 +1059,6 @@ materializeQueryResult(FunctionCallInfo fcinfo,
 			tuplestore_puttuple(tupstore, tuple);
 
 			PQclear(res);
-			res = NULL;
 		}
 		else
 		{
@@ -1083,26 +1067,20 @@ materializeQueryResult(FunctionCallInfo fcinfo,
 			Assert(rsinfo->setResult != NULL);
 
 			PQclear(res);
-			res = NULL;
 		}
 
 		/* clean up data conversion short-lived memory context */
 		if (sinfo.tmpcontext != NULL)
 			MemoryContextDelete(sinfo.tmpcontext);
-		sinfo.tmpcontext = NULL;
 
 		PQclear(sinfo.last_res);
-		sinfo.last_res = NULL;
 		PQclear(sinfo.cur_res);
-		sinfo.cur_res = NULL;
 	}
 	PG_CATCH();
 	{
-		/* be sure to release any libpq result we collected */
-		PQclear(res);
-		PQclear(sinfo.last_res);
-		PQclear(sinfo.cur_res);
-		/* and clear out any pending data in libpq */
+		PGresult   *res;
+
+		/* be sure to clear out any pending data in libpq */
 		while ((res = libpqsrv_get_result(conn, dblink_we_get_result)) !=
 			   NULL)
 			PQclear(res);
@@ -1115,7 +1093,7 @@ materializeQueryResult(FunctionCallInfo fcinfo,
  * Execute query, and send any result rows to sinfo->tuplestore.
  */
 static PGresult *
-storeQueryResult(volatile storeInfo *sinfo, PGconn *conn, const char *sql)
+storeQueryResult(storeInfo *sinfo, PGconn *conn, const char *sql)
 {
 	bool		first = true;
 	int			nestlevel = -1;
@@ -1183,7 +1161,7 @@ storeQueryResult(volatile storeInfo *sinfo, PGconn *conn, const char *sql)
  * (in this case the PGresult might contain either zero or one row).
  */
 static void
-storeRow(volatile storeInfo *sinfo, PGresult *res, bool first)
+storeRow(storeInfo *sinfo, PGresult *res, bool first)
 {
 	int			nfields = PQnfields(res);
 	HeapTuple	tuple;
@@ -2788,10 +2766,13 @@ dblink_connstr_check(const char *connstr)
 /*
  * Report an error received from the remote server
  *
- * res: the received error result (will be freed)
+ * res: the received error result
  * fail: true for ERROR ereport, false for NOTICE
  * fmt and following args: sprintf-style format and values for errcontext;
  * the resulting string should be worded like "while <some action>"
+ *
+ * If "res" is not NULL, it'll be PQclear'ed here (unless we throw error,
+ * in which case memory context cleanup will clear it eventually).
  */
 static void
 dblink_res_error(PGconn *conn, const char *conname, PGresult *res,
@@ -2799,15 +2780,11 @@ dblink_res_error(PGconn *conn, const char *conname, PGresult *res,
 {
 	int			level;
 	char	   *pg_diag_sqlstate = PQresultErrorField(res, PG_DIAG_SQLSTATE);
-	char	   *pg_diag_message_primary = PQresultErrorField(res, PG_DIAG_MESSAGE_PRIMARY);
-	char	   *pg_diag_message_detail = PQresultErrorField(res, PG_DIAG_MESSAGE_DETAIL);
-	char	   *pg_diag_message_hint = PQresultErrorField(res, PG_DIAG_MESSAGE_HINT);
-	char	   *pg_diag_context = PQresultErrorField(res, PG_DIAG_CONTEXT);
+	char	   *message_primary = PQresultErrorField(res, PG_DIAG_MESSAGE_PRIMARY);
+	char	   *message_detail = PQresultErrorField(res, PG_DIAG_MESSAGE_DETAIL);
+	char	   *message_hint = PQresultErrorField(res, PG_DIAG_MESSAGE_HINT);
+	char	   *message_context = PQresultErrorField(res, PG_DIAG_CONTEXT);
 	int			sqlstate;
-	char	   *message_primary;
-	char	   *message_detail;
-	char	   *message_hint;
-	char	   *message_context;
 	va_list		ap;
 	char		dblink_context_msg[512];
 
@@ -2825,11 +2802,6 @@ dblink_res_error(PGconn *conn, const char *conname, PGresult *res,
 	else
 		sqlstate = ERRCODE_CONNECTION_FAILURE;
 
-	message_primary = xpstrdup(pg_diag_message_primary);
-	message_detail = xpstrdup(pg_diag_message_detail);
-	message_hint = xpstrdup(pg_diag_message_hint);
-	message_context = xpstrdup(pg_diag_context);
-
 	/*
 	 * If we don't get a message from the PGresult, try the PGconn.  This is
 	 * needed because for connection-level failures, PQgetResult may just
@@ -2838,14 +2810,6 @@ dblink_res_error(PGconn *conn, const char *conname, PGresult *res,
 	if (message_primary == NULL)
 		message_primary = pchomp(PQerrorMessage(conn));
 
-	/*
-	 * Now that we've copied all the data we need out of the PGresult, it's
-	 * safe to free it.  We must do this to avoid PGresult leakage.  We're
-	 * leaking all the strings too, but those are in palloc'd memory that will
-	 * get cleaned up eventually.
-	 */
-	PQclear(res);
-
 	/*
 	 * Format the basic errcontext string.  Below, we'll add on something
 	 * about the connection name.  That's a violation of the translatability
@@ -2870,6 +2834,7 @@ dblink_res_error(PGconn *conn, const char *conname, PGresult *res,
 						 dblink_context_msg, conname)) :
 			 (errcontext("%s on unnamed dblink connection",
 						 dblink_context_msg))));
+	PQclear(res);
 }
 
 /*
diff --git a/contrib/dblink/meson.build b/contrib/dblink/meson.build
index dfd8eb6877e90..a19ce6cf4b924 100644
--- a/contrib/dblink/meson.build
+++ b/contrib/dblink/meson.build
@@ -34,7 +34,7 @@ tests += {
     'sql': [
       'dblink',
     ],
-    'regress_args': ['--dlpath', meson.build_root() / 'src/test/regress'],
+    'regress_args': ['--dlpath', meson.project_build_root() / 'src/test/regress'],
   },
   'tap': {
     'tests': [
diff --git a/contrib/hstore/hstore_gin.c b/contrib/hstore/hstore_gin.c
index 766c00bb6a735..2e5fa115924ba 100644
--- a/contrib/hstore/hstore_gin.c
+++ b/contrib/hstore/hstore_gin.c
@@ -127,7 +127,7 @@ gin_extract_hstore_query(PG_FUNCTION_ARGS)
 			/* Nulls in the array are ignored, cf hstoreArrayToPairs */
 			if (key_nulls[i])
 				continue;
-			item = makeitem(VARDATA(key_datums[i]), VARSIZE(key_datums[i]) - VARHDRSZ, KEYFLAG);
+			item = makeitem(VARDATA(DatumGetPointer(key_datums[i])), VARSIZE(DatumGetPointer(key_datums[i])) - VARHDRSZ, KEYFLAG);
 			entries[j++] = PointerGetDatum(item);
 		}
 
diff --git a/contrib/hstore/hstore_gist.c b/contrib/hstore/hstore_gist.c
index a3b08af385016..69515dc3d3fbd 100644
--- a/contrib/hstore/hstore_gist.c
+++ b/contrib/hstore/hstore_gist.c
@@ -576,7 +576,7 @@ ghstore_consistent(PG_FUNCTION_ARGS)
 
 			if (key_nulls[i])
 				continue;
-			crc = crc32_sz(VARDATA(key_datums[i]), VARSIZE(key_datums[i]) - VARHDRSZ);
+			crc = crc32_sz(VARDATA(DatumGetPointer(key_datums[i])), VARSIZE(DatumGetPointer(key_datums[i])) - VARHDRSZ);
 			if (!(GETBIT(sign, HASHVAL(crc, siglen))))
 				res = false;
 		}
@@ -599,7 +599,7 @@ ghstore_consistent(PG_FUNCTION_ARGS)
 
 			if (key_nulls[i])
 				continue;
-			crc = crc32_sz(VARDATA(key_datums[i]), VARSIZE(key_datums[i]) - VARHDRSZ);
+			crc = crc32_sz(VARDATA(DatumGetPointer(key_datums[i])), VARSIZE(DatumGetPointer(key_datums[i])) - VARHDRSZ);
 			if (GETBIT(sign, HASHVAL(crc, siglen)))
 				res = true;
 		}
diff --git a/contrib/hstore/hstore_io.c b/contrib/hstore/hstore_io.c
index 4f867e4bd1f1c..9c53877c4a582 100644
--- a/contrib/hstore/hstore_io.c
+++ b/contrib/hstore/hstore_io.c
@@ -684,22 +684,22 @@ hstore_from_arrays(PG_FUNCTION_ARGS)
 
 		if (!value_nulls || value_nulls[i])
 		{
-			pairs[i].key = VARDATA(key_datums[i]);
+			pairs[i].key = VARDATA(DatumGetPointer(key_datums[i]));
 			pairs[i].val = NULL;
 			pairs[i].keylen =
-				hstoreCheckKeyLen(VARSIZE(key_datums[i]) - VARHDRSZ);
+				hstoreCheckKeyLen(VARSIZE(DatumGetPointer(key_datums[i])) - VARHDRSZ);
 			pairs[i].vallen = 4;
 			pairs[i].isnull = true;
 			pairs[i].needfree = false;
 		}
 		else
 		{
-			pairs[i].key = VARDATA(key_datums[i]);
-			pairs[i].val = VARDATA(value_datums[i]);
+			pairs[i].key = VARDATA(DatumGetPointer(key_datums[i]));
+			pairs[i].val = VARDATA(DatumGetPointer(value_datums[i]));
 			pairs[i].keylen =
-				hstoreCheckKeyLen(VARSIZE(key_datums[i]) - VARHDRSZ);
+				hstoreCheckKeyLen(VARSIZE(DatumGetPointer(key_datums[i])) - VARHDRSZ);
 			pairs[i].vallen =
-				hstoreCheckValLen(VARSIZE(value_datums[i]) - VARHDRSZ);
+				hstoreCheckValLen(VARSIZE(DatumGetPointer(value_datums[i])) - VARHDRSZ);
 			pairs[i].isnull = false;
 			pairs[i].needfree = false;
 		}
@@ -778,22 +778,22 @@ hstore_from_array(PG_FUNCTION_ARGS)
 
 		if (in_nulls[i * 2 + 1])
 		{
-			pairs[i].key = VARDATA(in_datums[i * 2]);
+			pairs[i].key = VARDATA(DatumGetPointer(in_datums[i * 2]));
 			pairs[i].val = NULL;
 			pairs[i].keylen =
-				hstoreCheckKeyLen(VARSIZE(in_datums[i * 2]) - VARHDRSZ);
+				hstoreCheckKeyLen(VARSIZE(DatumGetPointer(in_datums[i * 2])) - VARHDRSZ);
 			pairs[i].vallen = 4;
 			pairs[i].isnull = true;
 			pairs[i].needfree = false;
 		}
 		else
 		{
-			pairs[i].key = VARDATA(in_datums[i * 2]);
-			pairs[i].val = VARDATA(in_datums[i * 2 + 1]);
+			pairs[i].key = VARDATA(DatumGetPointer(in_datums[i * 2]));
+			pairs[i].val = VARDATA(DatumGetPointer(in_datums[i * 2 + 1]));
 			pairs[i].keylen =
-				hstoreCheckKeyLen(VARSIZE(in_datums[i * 2]) - VARHDRSZ);
+				hstoreCheckKeyLen(VARSIZE(DatumGetPointer(in_datums[i * 2])) - VARHDRSZ);
 			pairs[i].vallen =
-				hstoreCheckValLen(VARSIZE(in_datums[i * 2 + 1]) - VARHDRSZ);
+				hstoreCheckValLen(VARSIZE(DatumGetPointer(in_datums[i * 2 + 1])) - VARHDRSZ);
 			pairs[i].isnull = false;
 			pairs[i].needfree = false;
 		}
diff --git a/contrib/hstore/hstore_op.c b/contrib/hstore/hstore_op.c
index 5e57eceffc817..bcba75f925808 100644
--- a/contrib/hstore/hstore_op.c
+++ b/contrib/hstore/hstore_op.c
@@ -107,8 +107,8 @@ hstoreArrayToPairs(ArrayType *a, int *npairs)
 	{
 		if (!key_nulls[i])
 		{
-			key_pairs[j].key = VARDATA(key_datums[i]);
-			key_pairs[j].keylen = VARSIZE(key_datums[i]) - VARHDRSZ;
+			key_pairs[j].key = VARDATA(DatumGetPointer(key_datums[i]));
+			key_pairs[j].keylen = VARSIZE(DatumGetPointer(key_datums[i])) - VARHDRSZ;
 			key_pairs[j].val = NULL;
 			key_pairs[j].vallen = 0;
 			key_pairs[j].needfree = 0;
diff --git a/contrib/isn/isn.c b/contrib/isn/isn.c
index 038c8ed4db7bd..1880c91844e90 100644
--- a/contrib/isn/isn.c
+++ b/contrib/isn/isn.c
@@ -726,7 +726,7 @@ string2ean(const char *str, struct Node *escontext, ean13 *result,
 			if (type != INVALID)
 				goto eaninvalid;
 			type = ISSN;
-			*aux1++ = toupper((unsigned char) *aux2);
+			*aux1++ = pg_ascii_toupper((unsigned char) *aux2);
 			length++;
 		}
 		else if (length == 9 && (digit || *aux2 == 'X' || *aux2 == 'x') && last)
@@ -736,7 +736,7 @@ string2ean(const char *str, struct Node *escontext, ean13 *result,
 				goto eaninvalid;
 			if (type == INVALID)
 				type = ISBN;	/* ISMN must start with 'M' */
-			*aux1++ = toupper((unsigned char) *aux2);
+			*aux1++ = pg_ascii_toupper((unsigned char) *aux2);
 			length++;
 		}
 		else if (length == 11 && digit && last)
diff --git a/contrib/pageinspect/btreefuncs.c b/contrib/pageinspect/btreefuncs.c
index 294821231fc3b..4e2e8891cddfd 100644
--- a/contrib/pageinspect/btreefuncs.c
+++ b/contrib/pageinspect/btreefuncs.c
@@ -506,7 +506,7 @@ bt_page_print_tuples(ua_page_items *uargs)
 
 	j = 0;
 	memset(nulls, 0, sizeof(nulls));
-	values[j++] = DatumGetInt16(offset);
+	values[j++] = Int16GetDatum(offset);
 	values[j++] = ItemPointerGetDatum(&itup->t_tid);
 	values[j++] = Int32GetDatum((int) IndexTupleSize(itup));
 	values[j++] = BoolGetDatum(IndexTupleHasNulls(itup));
diff --git a/contrib/pageinspect/expected/gist.out b/contrib/pageinspect/expected/gist.out
index 2b1d54a627949..8502f9efb4190 100644
--- a/contrib/pageinspect/expected/gist.out
+++ b/contrib/pageinspect/expected/gist.out
@@ -5,21 +5,21 @@ CREATE UNLOGGED TABLE test_gist AS SELECT point(i,i) p, i::text t FROM
 CREATE INDEX test_gist_idx ON test_gist USING gist (p);
 -- Page 0 is the root, the rest are leaf pages
 SELECT * FROM gist_page_opaque_info(get_raw_page('test_gist_idx', 0));
- lsn | nsn | rightlink  | flags 
------+-----+------------+-------
- 0/1 | 0/0 | 4294967295 | {}
+    lsn     |    nsn     | rightlink  | flags 
+------------+------------+------------+-------
+ 0/00000001 | 0/00000000 | 4294967295 | {}
 (1 row)
 
 SELECT * FROM gist_page_opaque_info(get_raw_page('test_gist_idx', 1));
- lsn | nsn | rightlink  | flags  
------+-----+------------+--------
- 0/1 | 0/0 | 4294967295 | {leaf}
+    lsn     |    nsn     | rightlink  | flags  
+------------+------------+------------+--------
+ 0/00000001 | 0/00000000 | 4294967295 | {leaf}
 (1 row)
 
 SELECT * FROM gist_page_opaque_info(get_raw_page('test_gist_idx', 2));
- lsn | nsn | rightlink | flags  
------+-----+-----------+--------
- 0/1 | 0/0 |         1 | {leaf}
+    lsn     |    nsn     | rightlink | flags  
+------------+------------+-----------+--------
+ 0/00000001 | 0/00000000 |         1 | {leaf}
 (1 row)
 
 SELECT * FROM gist_page_items(get_raw_page('test_gist_idx', 0), 'test_gist_idx');
diff --git a/contrib/pageinspect/expected/page.out b/contrib/pageinspect/expected/page.out
index e42fd9747fd1c..fcf19c5ca5a50 100644
--- a/contrib/pageinspect/expected/page.out
+++ b/contrib/pageinspect/expected/page.out
@@ -265,9 +265,9 @@ SELECT fsm_page_contents(decode(repeat('00', :block_size), 'hex'));
 (1 row)
 
 SELECT page_header(decode(repeat('00', :block_size), 'hex'));
-      page_header      
------------------------
- (0/0,0,0,0,0,0,0,0,0)
+         page_header          
+------------------------------
+ (0/00000000,0,0,0,0,0,0,0,0)
 (1 row)
 
 SELECT page_checksum(decode(repeat('00', :block_size), 'hex'), 1);
diff --git a/contrib/pageinspect/gistfuncs.c b/contrib/pageinspect/gistfuncs.c
index 7b16e2a1ef33c..1b299374890b0 100644
--- a/contrib/pageinspect/gistfuncs.c
+++ b/contrib/pageinspect/gistfuncs.c
@@ -174,7 +174,7 @@ gist_page_items_bytea(PG_FUNCTION_ARGS)
 
 		memset(nulls, 0, sizeof(nulls));
 
-		values[0] = DatumGetInt16(offset);
+		values[0] = Int16GetDatum(offset);
 		values[1] = ItemPointerGetDatum(&itup->t_tid);
 		values[2] = Int32GetDatum((int) IndexTupleSize(itup));
 
@@ -281,7 +281,7 @@ gist_page_items(PG_FUNCTION_ARGS)
 
 		memset(nulls, 0, sizeof(nulls));
 
-		values[0] = DatumGetInt16(offset);
+		values[0] = Int16GetDatum(offset);
 		values[1] = ItemPointerGetDatum(&itup->t_tid);
 		values[2] = Int32GetDatum((int) IndexTupleSize(itup));
 		values[3] = BoolGetDatum(ItemIdIsDead(id));
diff --git a/contrib/pageinspect/rawpage.c b/contrib/pageinspect/rawpage.c
index 0d57123aa2669..aef442b5db30a 100644
--- a/contrib/pageinspect/rawpage.c
+++ b/contrib/pageinspect/rawpage.c
@@ -282,7 +282,7 @@ page_header(PG_FUNCTION_ARGS)
 	{
 		char		lsnchar[64];
 
-		snprintf(lsnchar, sizeof(lsnchar), "%X/%X", LSN_FORMAT_ARGS(lsn));
+		snprintf(lsnchar, sizeof(lsnchar), "%X/%08X", LSN_FORMAT_ARGS(lsn));
 		values[0] = CStringGetTextDatum(lsnchar);
 	}
 	else
diff --git a/contrib/pg_buffercache/pg_buffercache_pages.c b/contrib/pg_buffercache/pg_buffercache_pages.c
index 4b007f6e1b06a..ae0291e6e96df 100644
--- a/contrib/pg_buffercache/pg_buffercache_pages.c
+++ b/contrib/pg_buffercache/pg_buffercache_pages.c
@@ -320,7 +320,6 @@ pg_buffercache_numa_pages(PG_FUNCTION_ARGS)
 		uint64		os_page_count;
 		int			pages_per_buffer;
 		int			max_entries;
-		volatile uint64 touch pg_attribute_unused();
 		char	   *startptr,
 				   *endptr;
 
@@ -375,7 +374,7 @@ pg_buffercache_numa_pages(PG_FUNCTION_ARGS)
 
 			/* Only need to touch memory once per backend process lifetime */
 			if (firstNumaTouch)
-				pg_numa_touch_mem_if_required(touch, ptr);
+				pg_numa_touch_mem_if_required(ptr);
 		}
 
 		Assert(idx == os_page_count);
diff --git a/contrib/pg_stat_statements/Makefile b/contrib/pg_stat_statements/Makefile
index b2bd8794d2a14..fe0478ac55266 100644
--- a/contrib/pg_stat_statements/Makefile
+++ b/contrib/pg_stat_statements/Makefile
@@ -7,6 +7,7 @@ OBJS = \
 
 EXTENSION = pg_stat_statements
 DATA = pg_stat_statements--1.4.sql \
+	pg_stat_statements--1.12--1.13.sql \
 	pg_stat_statements--1.11--1.12.sql pg_stat_statements--1.10--1.11.sql \
 	pg_stat_statements--1.9--1.10.sql pg_stat_statements--1.8--1.9.sql \
 	pg_stat_statements--1.7--1.8.sql pg_stat_statements--1.6--1.7.sql \
@@ -20,7 +21,7 @@ LDFLAGS_SL += $(filter -lm, $(LIBS))
 REGRESS_OPTS = --temp-config $(top_srcdir)/contrib/pg_stat_statements/pg_stat_statements.conf
 REGRESS = select dml cursors utility level_tracking planning \
 	user_activity wal entry_timestamp privileges extended \
-	parallel cleanup oldextversions squashing
+	parallel plancache cleanup oldextversions squashing
 # Disabled because these tests require "shared_preload_libraries=pg_stat_statements",
 # which typical installcheck users do not have (e.g. buildfarm clients).
 NO_INSTALLCHECK = 1
diff --git a/contrib/pg_stat_statements/expected/cursors.out b/contrib/pg_stat_statements/expected/cursors.out
index 0fc4b2c098d0e..6afb48ace9220 100644
--- a/contrib/pg_stat_statements/expected/cursors.out
+++ b/contrib/pg_stat_statements/expected/cursors.out
@@ -57,8 +57,8 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
      1 |    0 | COMMIT
      1 |    0 | DECLARE cursor_stats_1 CURSOR WITH HOLD FOR SELECT $1
      1 |    0 | DECLARE cursor_stats_2 CURSOR WITH HOLD FOR SELECT $1
-     1 |    1 | FETCH 1 IN cursor_stats_1
-     1 |    1 | FETCH 1 IN cursor_stats_2
+     1 |    1 | FETCH $1 IN cursor_stats_1
+     1 |    1 | FETCH $1 IN cursor_stats_2
      1 |    1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (9 rows)
 
@@ -68,3 +68,140 @@ SELECT pg_stat_statements_reset() IS NOT NULL AS t;
  t
 (1 row)
 
+-- Normalization of FETCH statements
+BEGIN;
+DECLARE pgss_cursor CURSOR FOR SELECT FROM generate_series(1, 10);
+-- implicit directions
+FETCH pgss_cursor;
+--
+(1 row)
+
+FETCH 1 pgss_cursor;
+--
+(1 row)
+
+FETCH 2 pgss_cursor;
+--
+(2 rows)
+
+FETCH -1 pgss_cursor;
+--
+(1 row)
+
+-- explicit NEXT
+FETCH NEXT pgss_cursor;
+--
+(1 row)
+
+-- explicit PRIOR
+FETCH PRIOR pgss_cursor;
+--
+(1 row)
+
+-- explicit FIRST
+FETCH FIRST pgss_cursor;
+--
+(1 row)
+
+-- explicit LAST
+FETCH LAST pgss_cursor;
+--
+(1 row)
+
+-- explicit ABSOLUTE
+FETCH ABSOLUTE 1 pgss_cursor;
+--
+(1 row)
+
+FETCH ABSOLUTE 2 pgss_cursor;
+--
+(1 row)
+
+FETCH ABSOLUTE -1 pgss_cursor;
+--
+(1 row)
+
+-- explicit RELATIVE
+FETCH RELATIVE 1 pgss_cursor;
+--
+(0 rows)
+
+FETCH RELATIVE 2 pgss_cursor;
+--
+(0 rows)
+
+FETCH RELATIVE -1 pgss_cursor;
+--
+(1 row)
+
+-- explicit FORWARD
+FETCH ALL pgss_cursor;
+--
+(0 rows)
+
+-- explicit FORWARD ALL
+FETCH FORWARD ALL pgss_cursor;
+--
+(0 rows)
+
+-- explicit FETCH FORWARD
+FETCH FORWARD pgss_cursor;
+--
+(0 rows)
+
+FETCH FORWARD 1 pgss_cursor;
+--
+(0 rows)
+
+FETCH FORWARD 2 pgss_cursor;
+--
+(0 rows)
+
+FETCH FORWARD -1 pgss_cursor;
+--
+(1 row)
+
+-- explicit FETCH BACKWARD
+FETCH BACKWARD pgss_cursor;
+--
+(1 row)
+
+FETCH BACKWARD 1 pgss_cursor;
+--
+(1 row)
+
+FETCH BACKWARD 2 pgss_cursor;
+--
+(2 rows)
+
+FETCH BACKWARD -1 pgss_cursor;
+--
+(1 row)
+
+-- explicit BACKWARD ALL
+FETCH BACKWARD ALL pgss_cursor;
+--
+(6 rows)
+
+COMMIT;
+SELECT calls, query FROM pg_stat_statements ORDER BY query COLLATE "C";
+ calls |                               query                                
+-------+--------------------------------------------------------------------
+     1 | BEGIN
+     1 | COMMIT
+     1 | DECLARE pgss_cursor CURSOR FOR SELECT FROM generate_series($1, $2)
+     3 | FETCH ABSOLUTE $1 pgss_cursor
+     1 | FETCH ALL pgss_cursor
+     1 | FETCH BACKWARD ALL pgss_cursor
+     4 | FETCH BACKWARD pgss_cursor
+     1 | FETCH FIRST pgss_cursor
+     1 | FETCH FORWARD ALL pgss_cursor
+     4 | FETCH FORWARD pgss_cursor
+     1 | FETCH LAST pgss_cursor
+     1 | FETCH NEXT pgss_cursor
+     1 | FETCH PRIOR pgss_cursor
+     3 | FETCH RELATIVE $1 pgss_cursor
+     4 | FETCH pgss_cursor
+     1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+(16 rows)
+
diff --git a/contrib/pg_stat_statements/expected/level_tracking.out b/contrib/pg_stat_statements/expected/level_tracking.out
index 8213fcd2e612c..8e8388dd5cb1f 100644
--- a/contrib/pg_stat_statements/expected/level_tracking.out
+++ b/contrib/pg_stat_statements/expected/level_tracking.out
@@ -1147,7 +1147,7 @@ SELECT toplevel, calls, query FROM pg_stat_statements
  t        |     1 | COMMIT
  t        |     1 | DECLARE FOOCUR CURSOR FOR SELECT * from stats_track_tab
  f        |     1 | DECLARE FOOCUR CURSOR FOR SELECT * from stats_track_tab;
- t        |     1 | FETCH FORWARD 1 FROM foocur
+ t        |     1 | FETCH FORWARD $1 FROM foocur
  t        |     1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (7 rows)
 
@@ -1176,7 +1176,7 @@ SELECT toplevel, calls, query FROM pg_stat_statements
  t        |     1 | CLOSE foocur
  t        |     1 | COMMIT
  t        |     1 | DECLARE FOOCUR CURSOR FOR SELECT * FROM stats_track_tab
- t        |     1 | FETCH FORWARD 1 FROM foocur
+ t        |     1 | FETCH FORWARD $1 FROM foocur
  t        |     1 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
 (6 rows)
 
diff --git a/contrib/pg_stat_statements/expected/oldextversions.out b/contrib/pg_stat_statements/expected/oldextversions.out
index de679b19711ab..726383a99d7c1 100644
--- a/contrib/pg_stat_statements/expected/oldextversions.out
+++ b/contrib/pg_stat_statements/expected/oldextversions.out
@@ -407,4 +407,71 @@ SELECT count(*) > 0 AS has_data FROM pg_stat_statements;
  t
 (1 row)
 
+-- New functions and views for pg_stat_statements in 1.13
+AlTER EXTENSION pg_stat_statements UPDATE TO '1.13';
+\d pg_stat_statements
+                            View "public.pg_stat_statements"
+           Column           |           Type           | Collation | Nullable | Default 
+----------------------------+--------------------------+-----------+----------+---------
+ userid                     | oid                      |           |          | 
+ dbid                       | oid                      |           |          | 
+ toplevel                   | boolean                  |           |          | 
+ queryid                    | bigint                   |           |          | 
+ query                      | text                     |           |          | 
+ plans                      | bigint                   |           |          | 
+ total_plan_time            | double precision         |           |          | 
+ min_plan_time              | double precision         |           |          | 
+ max_plan_time              | double precision         |           |          | 
+ mean_plan_time             | double precision         |           |          | 
+ stddev_plan_time           | double precision         |           |          | 
+ calls                      | bigint                   |           |          | 
+ total_exec_time            | double precision         |           |          | 
+ min_exec_time              | double precision         |           |          | 
+ max_exec_time              | double precision         |           |          | 
+ mean_exec_time             | double precision         |           |          | 
+ stddev_exec_time           | double precision         |           |          | 
+ rows                       | bigint                   |           |          | 
+ shared_blks_hit            | bigint                   |           |          | 
+ shared_blks_read           | bigint                   |           |          | 
+ shared_blks_dirtied        | bigint                   |           |          | 
+ shared_blks_written        | bigint                   |           |          | 
+ local_blks_hit             | bigint                   |           |          | 
+ local_blks_read            | bigint                   |           |          | 
+ local_blks_dirtied         | bigint                   |           |          | 
+ local_blks_written         | bigint                   |           |          | 
+ temp_blks_read             | bigint                   |           |          | 
+ temp_blks_written          | bigint                   |           |          | 
+ shared_blk_read_time       | double precision         |           |          | 
+ shared_blk_write_time      | double precision         |           |          | 
+ local_blk_read_time        | double precision         |           |          | 
+ local_blk_write_time       | double precision         |           |          | 
+ temp_blk_read_time         | double precision         |           |          | 
+ temp_blk_write_time        | double precision         |           |          | 
+ wal_records                | bigint                   |           |          | 
+ wal_fpi                    | bigint                   |           |          | 
+ wal_bytes                  | numeric                  |           |          | 
+ wal_buffers_full           | bigint                   |           |          | 
+ jit_functions              | bigint                   |           |          | 
+ jit_generation_time        | double precision         |           |          | 
+ jit_inlining_count         | bigint                   |           |          | 
+ jit_inlining_time          | double precision         |           |          | 
+ jit_optimization_count     | bigint                   |           |          | 
+ jit_optimization_time      | double precision         |           |          | 
+ jit_emission_count         | bigint                   |           |          | 
+ jit_emission_time          | double precision         |           |          | 
+ jit_deform_count           | bigint                   |           |          | 
+ jit_deform_time            | double precision         |           |          | 
+ parallel_workers_to_launch | bigint                   |           |          | 
+ parallel_workers_launched  | bigint                   |           |          | 
+ generic_plan_calls         | bigint                   |           |          | 
+ custom_plan_calls          | bigint                   |           |          | 
+ stats_since                | timestamp with time zone |           |          | 
+ minmax_stats_since         | timestamp with time zone |           |          | 
+
+SELECT count(*) > 0 AS has_data FROM pg_stat_statements;
+ has_data 
+----------
+ t
+(1 row)
+
 DROP EXTENSION pg_stat_statements;
diff --git a/contrib/pg_stat_statements/expected/plancache.out b/contrib/pg_stat_statements/expected/plancache.out
new file mode 100644
index 0000000000000..e152de9f55130
--- /dev/null
+++ b/contrib/pg_stat_statements/expected/plancache.out
@@ -0,0 +1,224 @@
+--
+-- Tests with plan cache
+--
+-- Setup
+CREATE OR REPLACE FUNCTION select_one_func(int) RETURNS VOID AS $$
+DECLARE
+  ret INT;
+BEGIN
+  SELECT $1 INTO ret;
+END;
+$$ LANGUAGE plpgsql;
+CREATE OR REPLACE PROCEDURE select_one_proc(int) AS $$
+DECLARE
+  ret INT;
+BEGIN
+  SELECT $1 INTO ret;
+END;
+$$ LANGUAGE plpgsql;
+-- Prepared statements
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+PREPARE p1 AS SELECT $1 AS a;
+SET plan_cache_mode TO force_generic_plan;
+EXECUTE p1(1);
+ a 
+---
+ 1
+(1 row)
+
+SET plan_cache_mode TO force_custom_plan;
+EXECUTE p1(1);
+ a 
+---
+ 1
+(1 row)
+
+SELECT calls, generic_plan_calls, custom_plan_calls, query FROM pg_stat_statements
+  ORDER BY query COLLATE "C";
+ calls | generic_plan_calls | custom_plan_calls |                       query                        
+-------+--------------------+-------------------+----------------------------------------------------
+     2 |                  1 |                 1 | PREPARE p1 AS SELECT $1 AS a
+     1 |                  0 |                 0 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+     2 |                  0 |                 0 | SET plan_cache_mode TO $1
+(3 rows)
+
+DEALLOCATE p1;
+-- Extended query protocol
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+SELECT $1 AS a \parse p1
+SET plan_cache_mode TO force_generic_plan;
+\bind_named p1 1
+;
+ a 
+---
+ 1
+(1 row)
+
+SET plan_cache_mode TO force_custom_plan;
+\bind_named p1 1
+;
+ a 
+---
+ 1
+(1 row)
+
+SELECT calls, generic_plan_calls, custom_plan_calls, query FROM pg_stat_statements
+  ORDER BY query COLLATE "C";
+ calls | generic_plan_calls | custom_plan_calls |                       query                        
+-------+--------------------+-------------------+----------------------------------------------------
+     2 |                  1 |                 1 | SELECT $1 AS a
+     1 |                  0 |                 0 | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+     2 |                  0 |                 0 | SET plan_cache_mode TO $1
+(3 rows)
+
+\close_prepared p1
+-- EXPLAIN [ANALYZE] EXECUTE
+SET pg_stat_statements.track = 'all';
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+PREPARE p1 AS SELECT $1;
+SET plan_cache_mode TO force_generic_plan;
+EXPLAIN (COSTS OFF) EXECUTE p1(1);
+ QUERY PLAN 
+------------
+ Result
+(1 row)
+
+EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF, BUFFERS OFF) EXECUTE p1(1);
+            QUERY PLAN             
+-----------------------------------
+ Result (actual rows=1.00 loops=1)
+(1 row)
+
+SET plan_cache_mode TO force_custom_plan;
+EXPLAIN (COSTS OFF) EXECUTE p1(1);
+ QUERY PLAN 
+------------
+ Result
+(1 row)
+
+EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF, BUFFERS OFF) EXECUTE p1(1);
+            QUERY PLAN             
+-----------------------------------
+ Result (actual rows=1.00 loops=1)
+(1 row)
+
+SELECT calls, generic_plan_calls, custom_plan_calls, toplevel, query FROM pg_stat_statements
+  ORDER BY query COLLATE "C";
+ calls | generic_plan_calls | custom_plan_calls | toplevel |                                      query                                       
+-------+--------------------+-------------------+----------+----------------------------------------------------------------------------------
+     2 |                  0 |                 0 | t        | EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF, BUFFERS OFF) EXECUTE p1(1)
+     2 |                  0 |                 0 | t        | EXPLAIN (COSTS OFF) EXECUTE p1(1)
+     4 |                  2 |                 2 | f        | PREPARE p1 AS SELECT $1
+     1 |                  0 |                 0 | t        | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+     2 |                  0 |                 0 | t        | SET plan_cache_mode TO $1
+(5 rows)
+
+RESET pg_stat_statements.track;
+DEALLOCATE p1;
+-- Functions/procedures
+SET pg_stat_statements.track = 'all';
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+SET plan_cache_mode TO force_generic_plan;
+SELECT select_one_func(1);
+ select_one_func 
+-----------------
+ 
+(1 row)
+
+CALL select_one_proc(1);
+SET plan_cache_mode TO force_custom_plan;
+SELECT select_one_func(1);
+ select_one_func 
+-----------------
+ 
+(1 row)
+
+CALL select_one_proc(1);
+SELECT calls, generic_plan_calls, custom_plan_calls, toplevel, query FROM pg_stat_statements
+  ORDER BY query COLLATE "C";
+ calls | generic_plan_calls | custom_plan_calls | toplevel |                       query                        
+-------+--------------------+-------------------+----------+----------------------------------------------------
+     2 |                  0 |                 0 | t        | CALL select_one_proc($1)
+     4 |                  2 |                 2 | f        | SELECT $1
+     1 |                  0 |                 0 | t        | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+     2 |                  0 |                 0 | t        | SELECT select_one_func($1)
+     2 |                  0 |                 0 | t        | SET plan_cache_mode TO $1
+(5 rows)
+
+--
+-- EXPLAIN [ANALYZE] EXECUTE + functions/procedures
+--
+SET pg_stat_statements.track = 'all';
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+ t 
+---
+ t
+(1 row)
+
+SET plan_cache_mode TO force_generic_plan;
+EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF, BUFFERS OFF) SELECT select_one_func(1);
+            QUERY PLAN             
+-----------------------------------
+ Result (actual rows=1.00 loops=1)
+(1 row)
+
+EXPLAIN (COSTS OFF) SELECT select_one_func(1);
+ QUERY PLAN 
+------------
+ Result
+(1 row)
+
+CALL select_one_proc(1);
+SET plan_cache_mode TO force_custom_plan;
+EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF, BUFFERS OFF) SELECT select_one_func(1);
+            QUERY PLAN             
+-----------------------------------
+ Result (actual rows=1.00 loops=1)
+(1 row)
+
+EXPLAIN (COSTS OFF) SELECT select_one_func(1);
+ QUERY PLAN 
+------------
+ Result
+(1 row)
+
+CALL select_one_proc(1);
+SELECT calls, generic_plan_calls, custom_plan_calls, toplevel, query FROM pg_stat_statements
+  ORDER BY query COLLATE "C", toplevel;
+ calls | generic_plan_calls | custom_plan_calls | toplevel |                                             query                                              
+-------+--------------------+-------------------+----------+------------------------------------------------------------------------------------------------
+     2 |                  0 |                 0 | t        | CALL select_one_proc($1)
+     2 |                  0 |                 0 | t        | EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF, BUFFERS OFF) SELECT select_one_func($1)
+     4 |                  0 |                 0 | f        | EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF, BUFFERS OFF) SELECT select_one_func($1);
+     2 |                  0 |                 0 | t        | EXPLAIN (COSTS OFF) SELECT select_one_func($1)
+     4 |                  2 |                 2 | f        | SELECT $1
+     1 |                  0 |                 0 | t        | SELECT pg_stat_statements_reset() IS NOT NULL AS t
+     2 |                  0 |                 0 | t        | SET plan_cache_mode TO $1
+(7 rows)
+
+RESET pg_stat_statements.track;
+--
+-- Cleanup
+--
+DROP FUNCTION select_one_func(int);
+DROP PROCEDURE select_one_proc(int);
diff --git a/contrib/pg_stat_statements/expected/utility.out b/contrib/pg_stat_statements/expected/utility.out
index 060d4416dd749..e4d6564ea5b5a 100644
--- a/contrib/pg_stat_statements/expected/utility.out
+++ b/contrib/pg_stat_statements/expected/utility.out
@@ -702,7 +702,7 @@ SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
      1 |   13 | CREATE MATERIALIZED VIEW pgss_matv AS SELECT * FROM pgss_ctas
      1 |   10 | CREATE TABLE pgss_ctas AS SELECT a, $1 b FROM generate_series($2, $3) a
      1 |    0 | DECLARE pgss_cursor CURSOR FOR SELECT * FROM pgss_matv
-     1 |    5 | FETCH FORWARD 5 pgss_cursor
+     1 |    5 | FETCH FORWARD $1 pgss_cursor
      1 |    7 | FETCH FORWARD ALL pgss_cursor
      1 |    1 | FETCH NEXT pgss_cursor
      1 |   13 | REFRESH MATERIALIZED VIEW pgss_matv
diff --git a/contrib/pg_stat_statements/meson.build b/contrib/pg_stat_statements/meson.build
index 01a6cbdcf6139..7b8bfbb1de78c 100644
--- a/contrib/pg_stat_statements/meson.build
+++ b/contrib/pg_stat_statements/meson.build
@@ -21,6 +21,7 @@ contrib_targets += pg_stat_statements
 install_data(
   'pg_stat_statements.control',
   'pg_stat_statements--1.4.sql',
+  'pg_stat_statements--1.12--1.13.sql',
   'pg_stat_statements--1.11--1.12.sql',
   'pg_stat_statements--1.10--1.11.sql',
   'pg_stat_statements--1.9--1.10.sql',
@@ -54,6 +55,7 @@ tests += {
       'privileges',
       'extended',
       'parallel',
+      'plancache',
       'cleanup',
       'oldextversions',
       'squashing',
diff --git a/contrib/pg_stat_statements/pg_stat_statements--1.12--1.13.sql b/contrib/pg_stat_statements/pg_stat_statements--1.12--1.13.sql
new file mode 100644
index 0000000000000..2f0eaf14ec34d
--- /dev/null
+++ b/contrib/pg_stat_statements/pg_stat_statements--1.12--1.13.sql
@@ -0,0 +1,78 @@
+/* contrib/pg_stat_statements/pg_stat_statements--1.12--1.13.sql */
+
+-- complain if script is sourced in psql, rather than via ALTER EXTENSION
+\echo Use "ALTER EXTENSION pg_stat_statements UPDATE TO '1.13'" to load this file. \quit
+
+/* First we have to remove them from the extension */
+ALTER EXTENSION pg_stat_statements DROP VIEW pg_stat_statements;
+ALTER EXTENSION pg_stat_statements DROP FUNCTION pg_stat_statements(boolean);
+
+/* Then we can drop them */
+DROP VIEW pg_stat_statements;
+DROP FUNCTION pg_stat_statements(boolean);
+
+/* Now redefine */
+CREATE FUNCTION pg_stat_statements(IN showtext boolean,
+    OUT userid oid,
+    OUT dbid oid,
+    OUT toplevel bool,
+    OUT queryid bigint,
+    OUT query text,
+    OUT plans int8,
+    OUT total_plan_time float8,
+    OUT min_plan_time float8,
+    OUT max_plan_time float8,
+    OUT mean_plan_time float8,
+    OUT stddev_plan_time float8,
+    OUT calls int8,
+    OUT total_exec_time float8,
+    OUT min_exec_time float8,
+    OUT max_exec_time float8,
+    OUT mean_exec_time float8,
+    OUT stddev_exec_time float8,
+    OUT rows int8,
+    OUT shared_blks_hit int8,
+    OUT shared_blks_read int8,
+    OUT shared_blks_dirtied int8,
+    OUT shared_blks_written int8,
+    OUT local_blks_hit int8,
+    OUT local_blks_read int8,
+    OUT local_blks_dirtied int8,
+    OUT local_blks_written int8,
+    OUT temp_blks_read int8,
+    OUT temp_blks_written int8,
+    OUT shared_blk_read_time float8,
+    OUT shared_blk_write_time float8,
+    OUT local_blk_read_time float8,
+    OUT local_blk_write_time float8,
+    OUT temp_blk_read_time float8,
+    OUT temp_blk_write_time float8,
+    OUT wal_records int8,
+    OUT wal_fpi int8,
+    OUT wal_bytes numeric,
+    OUT wal_buffers_full int8,
+    OUT jit_functions int8,
+    OUT jit_generation_time float8,
+    OUT jit_inlining_count int8,
+    OUT jit_inlining_time float8,
+    OUT jit_optimization_count int8,
+    OUT jit_optimization_time float8,
+    OUT jit_emission_count int8,
+    OUT jit_emission_time float8,
+    OUT jit_deform_count int8,
+    OUT jit_deform_time float8,
+    OUT parallel_workers_to_launch int8,
+    OUT parallel_workers_launched int8,
+    OUT generic_plan_calls int8,
+    OUT custom_plan_calls int8,
+    OUT stats_since timestamp with time zone,
+    OUT minmax_stats_since timestamp with time zone
+)
+RETURNS SETOF record
+AS 'MODULE_PATHNAME', 'pg_stat_statements_1_13'
+LANGUAGE C STRICT VOLATILE PARALLEL SAFE;
+
+CREATE VIEW pg_stat_statements AS
+  SELECT * FROM pg_stat_statements(true);
+
+GRANT SELECT ON pg_stat_statements TO PUBLIC;
diff --git a/contrib/pg_stat_statements/pg_stat_statements.c b/contrib/pg_stat_statements/pg_stat_statements.c
index e7857f81ec057..9fc9635d3300d 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.c
+++ b/contrib/pg_stat_statements/pg_stat_statements.c
@@ -85,7 +85,7 @@ PG_MODULE_MAGIC_EXT(
 #define PGSS_TEXT_FILE	PG_STAT_TMP_DIR "/pgss_query_texts.stat"
 
 /* Magic number identifying the stats file format */
-static const uint32 PGSS_FILE_HEADER = 0x20220408;
+static const uint32 PGSS_FILE_HEADER = 0x20250731;
 
 /* PostgreSQL major version number, changes in which invalidate all entries */
 static const uint32 PGSS_PG_MAJOR_VERSION = PG_VERSION_NUM / 100;
@@ -114,6 +114,7 @@ typedef enum pgssVersion
 	PGSS_V1_10,
 	PGSS_V1_11,
 	PGSS_V1_12,
+	PGSS_V1_13,
 } pgssVersion;
 
 typedef enum pgssStoreKind
@@ -210,6 +211,8 @@ typedef struct Counters
 											 * to be launched */
 	int64		parallel_workers_launched;	/* # of parallel workers actually
 											 * launched */
+	int64		generic_plan_calls; /* number of calls using a generic plan */
+	int64		custom_plan_calls;	/* number of calls using a custom plan */
 } Counters;
 
 /*
@@ -323,6 +326,7 @@ PG_FUNCTION_INFO_V1(pg_stat_statements_1_9);
 PG_FUNCTION_INFO_V1(pg_stat_statements_1_10);
 PG_FUNCTION_INFO_V1(pg_stat_statements_1_11);
 PG_FUNCTION_INFO_V1(pg_stat_statements_1_12);
+PG_FUNCTION_INFO_V1(pg_stat_statements_1_13);
 PG_FUNCTION_INFO_V1(pg_stat_statements);
 PG_FUNCTION_INFO_V1(pg_stat_statements_info);
 
@@ -355,7 +359,8 @@ static void pgss_store(const char *query, int64 queryId,
 					   const struct JitInstrumentation *jitusage,
 					   JumbleState *jstate,
 					   int parallel_workers_to_launch,
-					   int parallel_workers_launched);
+					   int parallel_workers_launched,
+					   PlannedStmtOrigin planOrigin);
 static void pg_stat_statements_internal(FunctionCallInfo fcinfo,
 										pgssVersion api_version,
 										bool showtext);
@@ -877,7 +882,8 @@ pgss_post_parse_analyze(ParseState *pstate, Query *query, JumbleState *jstate)
 				   NULL,
 				   jstate,
 				   0,
-				   0);
+				   0,
+				   PLAN_STMT_UNKNOWN);
 }
 
 /*
@@ -957,7 +963,8 @@ pgss_planner(Query *parse,
 				   NULL,
 				   NULL,
 				   0,
-				   0);
+				   0,
+				   result->planOrigin);
 	}
 	else
 	{
@@ -1091,7 +1098,8 @@ pgss_ExecutorEnd(QueryDesc *queryDesc)
 				   queryDesc->estate->es_jit ? &queryDesc->estate->es_jit->instr : NULL,
 				   NULL,
 				   queryDesc->estate->es_parallel_workers_to_launch,
-				   queryDesc->estate->es_parallel_workers_launched);
+				   queryDesc->estate->es_parallel_workers_launched,
+				   queryDesc->plannedstmt->planOrigin);
 	}
 
 	if (prev_ExecutorEnd)
@@ -1224,7 +1232,8 @@ pgss_ProcessUtility(PlannedStmt *pstmt, const char *queryString,
 				   NULL,
 				   NULL,
 				   0,
-				   0);
+				   0,
+				   pstmt->planOrigin);
 	}
 	else
 	{
@@ -1287,7 +1296,8 @@ pgss_store(const char *query, int64 queryId,
 		   const struct JitInstrumentation *jitusage,
 		   JumbleState *jstate,
 		   int parallel_workers_to_launch,
-		   int parallel_workers_launched)
+		   int parallel_workers_launched,
+		   PlannedStmtOrigin planOrigin)
 {
 	pgssHashKey key;
 	pgssEntry  *entry;
@@ -1495,6 +1505,12 @@ pgss_store(const char *query, int64 queryId,
 		entry->counters.parallel_workers_to_launch += parallel_workers_to_launch;
 		entry->counters.parallel_workers_launched += parallel_workers_launched;
 
+		/* plan cache counters */
+		if (planOrigin == PLAN_STMT_CACHE_GENERIC)
+			entry->counters.generic_plan_calls++;
+		else if (planOrigin == PLAN_STMT_CACHE_CUSTOM)
+			entry->counters.custom_plan_calls++;
+
 		SpinLockRelease(&entry->mutex);
 	}
 
@@ -1562,7 +1578,8 @@ pg_stat_statements_reset(PG_FUNCTION_ARGS)
 #define PG_STAT_STATEMENTS_COLS_V1_10	43
 #define PG_STAT_STATEMENTS_COLS_V1_11	49
 #define PG_STAT_STATEMENTS_COLS_V1_12	52
-#define PG_STAT_STATEMENTS_COLS			52	/* maximum of above */
+#define PG_STAT_STATEMENTS_COLS_V1_13	54
+#define PG_STAT_STATEMENTS_COLS			54	/* maximum of above */
 
 /*
  * Retrieve statement statistics.
@@ -1574,6 +1591,16 @@ pg_stat_statements_reset(PG_FUNCTION_ARGS)
  * expected API version is identified by embedding it in the C name of the
  * function.  Unfortunately we weren't bright enough to do that for 1.1.
  */
+Datum
+pg_stat_statements_1_13(PG_FUNCTION_ARGS)
+{
+	bool		showtext = PG_GETARG_BOOL(0);
+
+	pg_stat_statements_internal(fcinfo, PGSS_V1_13, showtext);
+
+	return (Datum) 0;
+}
+
 Datum
 pg_stat_statements_1_12(PG_FUNCTION_ARGS)
 {
@@ -1732,6 +1759,10 @@ pg_stat_statements_internal(FunctionCallInfo fcinfo,
 			if (api_version != PGSS_V1_12)
 				elog(ERROR, "incorrect number of output arguments");
 			break;
+		case PG_STAT_STATEMENTS_COLS_V1_13:
+			if (api_version != PGSS_V1_13)
+				elog(ERROR, "incorrect number of output arguments");
+			break;
 		default:
 			elog(ERROR, "incorrect number of output arguments");
 	}
@@ -1984,6 +2015,11 @@ pg_stat_statements_internal(FunctionCallInfo fcinfo,
 			values[i++] = Int64GetDatumFast(tmp.parallel_workers_to_launch);
 			values[i++] = Int64GetDatumFast(tmp.parallel_workers_launched);
 		}
+		if (api_version >= PGSS_V1_13)
+		{
+			values[i++] = Int64GetDatumFast(tmp.generic_plan_calls);
+			values[i++] = Int64GetDatumFast(tmp.custom_plan_calls);
+		}
 		if (api_version >= PGSS_V1_11)
 		{
 			values[i++] = TimestampTzGetDatum(stats_since);
@@ -1999,6 +2035,7 @@ pg_stat_statements_internal(FunctionCallInfo fcinfo,
 					 api_version == PGSS_V1_10 ? PG_STAT_STATEMENTS_COLS_V1_10 :
 					 api_version == PGSS_V1_11 ? PG_STAT_STATEMENTS_COLS_V1_11 :
 					 api_version == PGSS_V1_12 ? PG_STAT_STATEMENTS_COLS_V1_12 :
+					 api_version == PGSS_V1_13 ? PG_STAT_STATEMENTS_COLS_V1_13 :
 					 -1 /* fail if you forget to update this assert */ ));
 
 		tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
diff --git a/contrib/pg_stat_statements/pg_stat_statements.control b/contrib/pg_stat_statements/pg_stat_statements.control
index d45ebc12e3605..2eee0ceffa894 100644
--- a/contrib/pg_stat_statements/pg_stat_statements.control
+++ b/contrib/pg_stat_statements/pg_stat_statements.control
@@ -1,5 +1,5 @@
 # pg_stat_statements extension
 comment = 'track planning and execution statistics of all SQL statements executed'
-default_version = '1.12'
+default_version = '1.13'
 module_pathname = '$libdir/pg_stat_statements'
 relocatable = true
diff --git a/contrib/pg_stat_statements/sql/cursors.sql b/contrib/pg_stat_statements/sql/cursors.sql
index 61738ac470e82..78bb42284331f 100644
--- a/contrib/pg_stat_statements/sql/cursors.sql
+++ b/contrib/pg_stat_statements/sql/cursors.sql
@@ -28,3 +28,46 @@ COMMIT;
 
 SELECT calls, rows, query FROM pg_stat_statements ORDER BY query COLLATE "C";
 SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+
+-- Normalization of FETCH statements
+BEGIN;
+DECLARE pgss_cursor CURSOR FOR SELECT FROM generate_series(1, 10);
+-- implicit directions
+FETCH pgss_cursor;
+FETCH 1 pgss_cursor;
+FETCH 2 pgss_cursor;
+FETCH -1 pgss_cursor;
+-- explicit NEXT
+FETCH NEXT pgss_cursor;
+-- explicit PRIOR
+FETCH PRIOR pgss_cursor;
+-- explicit FIRST
+FETCH FIRST pgss_cursor;
+-- explicit LAST
+FETCH LAST pgss_cursor;
+-- explicit ABSOLUTE
+FETCH ABSOLUTE 1 pgss_cursor;
+FETCH ABSOLUTE 2 pgss_cursor;
+FETCH ABSOLUTE -1 pgss_cursor;
+-- explicit RELATIVE
+FETCH RELATIVE 1 pgss_cursor;
+FETCH RELATIVE 2 pgss_cursor;
+FETCH RELATIVE -1 pgss_cursor;
+-- explicit FORWARD
+FETCH ALL pgss_cursor;
+-- explicit FORWARD ALL
+FETCH FORWARD ALL pgss_cursor;
+-- explicit FETCH FORWARD
+FETCH FORWARD pgss_cursor;
+FETCH FORWARD 1 pgss_cursor;
+FETCH FORWARD 2 pgss_cursor;
+FETCH FORWARD -1 pgss_cursor;
+-- explicit FETCH BACKWARD
+FETCH BACKWARD pgss_cursor;
+FETCH BACKWARD 1 pgss_cursor;
+FETCH BACKWARD 2 pgss_cursor;
+FETCH BACKWARD -1 pgss_cursor;
+-- explicit BACKWARD ALL
+FETCH BACKWARD ALL pgss_cursor;
+COMMIT;
+SELECT calls, query FROM pg_stat_statements ORDER BY query COLLATE "C";
diff --git a/contrib/pg_stat_statements/sql/oldextversions.sql b/contrib/pg_stat_statements/sql/oldextversions.sql
index 13b8ca28586d1..e416efe9ffbee 100644
--- a/contrib/pg_stat_statements/sql/oldextversions.sql
+++ b/contrib/pg_stat_statements/sql/oldextversions.sql
@@ -63,4 +63,9 @@ AlTER EXTENSION pg_stat_statements UPDATE TO '1.12';
 \d pg_stat_statements
 SELECT count(*) > 0 AS has_data FROM pg_stat_statements;
 
+-- New functions and views for pg_stat_statements in 1.13
+AlTER EXTENSION pg_stat_statements UPDATE TO '1.13';
+\d pg_stat_statements
+SELECT count(*) > 0 AS has_data FROM pg_stat_statements;
+
 DROP EXTENSION pg_stat_statements;
diff --git a/contrib/pg_stat_statements/sql/plancache.sql b/contrib/pg_stat_statements/sql/plancache.sql
new file mode 100644
index 0000000000000..160ced7add368
--- /dev/null
+++ b/contrib/pg_stat_statements/sql/plancache.sql
@@ -0,0 +1,94 @@
+--
+-- Tests with plan cache
+--
+
+-- Setup
+CREATE OR REPLACE FUNCTION select_one_func(int) RETURNS VOID AS $$
+DECLARE
+  ret INT;
+BEGIN
+  SELECT $1 INTO ret;
+END;
+$$ LANGUAGE plpgsql;
+CREATE OR REPLACE PROCEDURE select_one_proc(int) AS $$
+DECLARE
+  ret INT;
+BEGIN
+  SELECT $1 INTO ret;
+END;
+$$ LANGUAGE plpgsql;
+
+-- Prepared statements
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+PREPARE p1 AS SELECT $1 AS a;
+SET plan_cache_mode TO force_generic_plan;
+EXECUTE p1(1);
+SET plan_cache_mode TO force_custom_plan;
+EXECUTE p1(1);
+SELECT calls, generic_plan_calls, custom_plan_calls, query FROM pg_stat_statements
+  ORDER BY query COLLATE "C";
+DEALLOCATE p1;
+
+-- Extended query protocol
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+SELECT $1 AS a \parse p1
+SET plan_cache_mode TO force_generic_plan;
+\bind_named p1 1
+;
+SET plan_cache_mode TO force_custom_plan;
+\bind_named p1 1
+;
+SELECT calls, generic_plan_calls, custom_plan_calls, query FROM pg_stat_statements
+  ORDER BY query COLLATE "C";
+\close_prepared p1
+
+-- EXPLAIN [ANALYZE] EXECUTE
+SET pg_stat_statements.track = 'all';
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+PREPARE p1 AS SELECT $1;
+SET plan_cache_mode TO force_generic_plan;
+EXPLAIN (COSTS OFF) EXECUTE p1(1);
+EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF, BUFFERS OFF) EXECUTE p1(1);
+SET plan_cache_mode TO force_custom_plan;
+EXPLAIN (COSTS OFF) EXECUTE p1(1);
+EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF, BUFFERS OFF) EXECUTE p1(1);
+SELECT calls, generic_plan_calls, custom_plan_calls, toplevel, query FROM pg_stat_statements
+  ORDER BY query COLLATE "C";
+RESET pg_stat_statements.track;
+DEALLOCATE p1;
+
+-- Functions/procedures
+SET pg_stat_statements.track = 'all';
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+SET plan_cache_mode TO force_generic_plan;
+SELECT select_one_func(1);
+CALL select_one_proc(1);
+SET plan_cache_mode TO force_custom_plan;
+SELECT select_one_func(1);
+CALL select_one_proc(1);
+SELECT calls, generic_plan_calls, custom_plan_calls, toplevel, query FROM pg_stat_statements
+  ORDER BY query COLLATE "C";
+
+--
+-- EXPLAIN [ANALYZE] EXECUTE + functions/procedures
+--
+SET pg_stat_statements.track = 'all';
+SELECT pg_stat_statements_reset() IS NOT NULL AS t;
+SET plan_cache_mode TO force_generic_plan;
+EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF, BUFFERS OFF) SELECT select_one_func(1);
+EXPLAIN (COSTS OFF) SELECT select_one_func(1);
+CALL select_one_proc(1);
+SET plan_cache_mode TO force_custom_plan;
+EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF, BUFFERS OFF) SELECT select_one_func(1);
+EXPLAIN (COSTS OFF) SELECT select_one_func(1);
+CALL select_one_proc(1);
+SELECT calls, generic_plan_calls, custom_plan_calls, toplevel, query FROM pg_stat_statements
+  ORDER BY query COLLATE "C", toplevel;
+
+RESET pg_stat_statements.track;
+
+--
+-- Cleanup
+--
+DROP FUNCTION select_one_func(int);
+DROP PROCEDURE select_one_proc(int);
diff --git a/contrib/pg_walinspect/expected/pg_walinspect.out b/contrib/pg_walinspect/expected/pg_walinspect.out
index c010eed8c5d6e..f955ff5d3c52a 100644
--- a/contrib/pg_walinspect/expected/pg_walinspect.out
+++ b/contrib/pg_walinspect/expected/pg_walinspect.out
@@ -19,14 +19,14 @@ INSERT INTO sample_tbl SELECT * FROM generate_series(3, 4);
 -- ===================================================================
 -- Invalid input LSN.
 SELECT * FROM pg_get_wal_record_info('0/0');
-ERROR:  could not read WAL at LSN 0/0
+ERROR:  could not read WAL at LSN 0/00000000
 -- Invalid start LSN.
 SELECT * FROM pg_get_wal_records_info('0/0', :'wal_lsn1');
-ERROR:  could not read WAL at LSN 0/0
+ERROR:  could not read WAL at LSN 0/00000000
 SELECT * FROM pg_get_wal_stats('0/0', :'wal_lsn1');
-ERROR:  could not read WAL at LSN 0/0
+ERROR:  could not read WAL at LSN 0/00000000
 SELECT * FROM pg_get_wal_block_info('0/0', :'wal_lsn1');
-ERROR:  could not read WAL at LSN 0/0
+ERROR:  could not read WAL at LSN 0/00000000
 -- Start LSN > End LSN.
 SELECT * FROM pg_get_wal_records_info(:'wal_lsn2', :'wal_lsn1');
 ERROR:  WAL start LSN must be less than end LSN
diff --git a/contrib/pg_walinspect/pg_walinspect.c b/contrib/pg_walinspect/pg_walinspect.c
index 64745564cc249..0398ad82cec90 100644
--- a/contrib/pg_walinspect/pg_walinspect.c
+++ b/contrib/pg_walinspect/pg_walinspect.c
@@ -105,7 +105,7 @@ InitXLogReaderState(XLogRecPtr lsn)
 	if (lsn < XLOG_BLCKSZ)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("could not read WAL at LSN %X/%X",
+				 errmsg("could not read WAL at LSN %X/%08X",
 						LSN_FORMAT_ARGS(lsn))));
 
 	private_data = (ReadLocalXLogPageNoWaitPrivate *)
@@ -128,8 +128,8 @@ InitXLogReaderState(XLogRecPtr lsn)
 
 	if (XLogRecPtrIsInvalid(first_valid_record))
 		ereport(ERROR,
-				(errmsg("could not find a valid record after %X/%X",
-						LSN_FORMAT_ARGS(lsn))));
+				errmsg("could not find a valid record after %X/%08X",
+					   LSN_FORMAT_ARGS(lsn)));
 
 	return xlogreader;
 }
@@ -168,12 +168,12 @@ ReadNextXLogRecord(XLogReaderState *xlogreader)
 		if (errormsg)
 			ereport(ERROR,
 					(errcode_for_file_access(),
-					 errmsg("could not read WAL at %X/%X: %s",
+					 errmsg("could not read WAL at %X/%08X: %s",
 							LSN_FORMAT_ARGS(xlogreader->EndRecPtr), errormsg)));
 		else
 			ereport(ERROR,
 					(errcode_for_file_access(),
-					 errmsg("could not read WAL at %X/%X",
+					 errmsg("could not read WAL at %X/%08X",
 							LSN_FORMAT_ARGS(xlogreader->EndRecPtr))));
 	}
 
@@ -479,7 +479,7 @@ pg_get_wal_record_info(PG_FUNCTION_ARGS)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("WAL input LSN must be less than current LSN"),
-				 errdetail("Current WAL LSN on the database system is at %X/%X.",
+				 errdetail("Current WAL LSN on the database system is at %X/%08X.",
 						   LSN_FORMAT_ARGS(curr_lsn))));
 
 	/* Build a tuple descriptor for our result type. */
@@ -491,7 +491,7 @@ pg_get_wal_record_info(PG_FUNCTION_ARGS)
 	if (!ReadNextXLogRecord(xlogreader))
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("could not read WAL at %X/%X",
+				 errmsg("could not read WAL at %X/%08X",
 						LSN_FORMAT_ARGS(xlogreader->EndRecPtr))));
 
 	GetWALRecordInfo(xlogreader, values, nulls, PG_GET_WAL_RECORD_INFO_COLS);
@@ -521,7 +521,7 @@ ValidateInputLSNs(XLogRecPtr start_lsn, XLogRecPtr *end_lsn)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("WAL start LSN must be less than current LSN"),
-				 errdetail("Current WAL LSN on the database system is at %X/%X.",
+				 errdetail("Current WAL LSN on the database system is at %X/%08X.",
 						   LSN_FORMAT_ARGS(curr_lsn))));
 
 	if (start_lsn > *end_lsn)
@@ -827,7 +827,7 @@ pg_get_wal_records_info_till_end_of_wal(PG_FUNCTION_ARGS)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("WAL start LSN must be less than current LSN"),
-				 errdetail("Current WAL LSN on the database system is at %X/%X.",
+				 errdetail("Current WAL LSN on the database system is at %X/%08X.",
 						   LSN_FORMAT_ARGS(end_lsn))));
 
 	GetWALRecordsInfo(fcinfo, start_lsn, end_lsn);
@@ -846,7 +846,7 @@ pg_get_wal_stats_till_end_of_wal(PG_FUNCTION_ARGS)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("WAL start LSN must be less than current LSN"),
-				 errdetail("Current WAL LSN on the database system is at %X/%X.",
+				 errdetail("Current WAL LSN on the database system is at %X/%08X.",
 						   LSN_FORMAT_ARGS(end_lsn))));
 
 	GetWalStats(fcinfo, start_lsn, end_lsn, stats_per_record);
diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c
index 304f3c20f8356..e8148f2c5a223 100644
--- a/contrib/postgres_fdw/connection.c
+++ b/contrib/postgres_fdw/connection.c
@@ -142,6 +142,8 @@ static void do_sql_command_begin(PGconn *conn, const char *sql);
 static void do_sql_command_end(PGconn *conn, const char *sql,
 							   bool consume_input);
 static void begin_remote_xact(ConnCacheEntry *entry);
+static void pgfdw_report_internal(int elevel, PGresult *res, PGconn *conn,
+								  const char *sql);
 static void pgfdw_xact_callback(XactEvent event, void *arg);
 static void pgfdw_subxact_callback(SubXactEvent event,
 								   SubTransactionId mySubid,
@@ -625,6 +627,9 @@ connect_pg_server(ForeignServer *server, UserMapping *user)
 							server->servername),
 					 errdetail_internal("%s", pchomp(PQerrorMessage(conn)))));
 
+		PQsetNoticeReceiver(conn, libpqsrv_notice_receiver,
+							"received message via remote connection");
+
 		/* Perform post-connection security checks. */
 		pgfdw_security_check(keywords, values, user, conn);
 
@@ -812,7 +817,7 @@ static void
 do_sql_command_begin(PGconn *conn, const char *sql)
 {
 	if (!PQsendQuery(conn, sql))
-		pgfdw_report_error(ERROR, NULL, conn, false, sql);
+		pgfdw_report_error(NULL, conn, sql);
 }
 
 static void
@@ -827,10 +832,10 @@ do_sql_command_end(PGconn *conn, const char *sql, bool consume_input)
 	 * would be large compared to the overhead of PQconsumeInput.)
 	 */
 	if (consume_input && !PQconsumeInput(conn))
-		pgfdw_report_error(ERROR, NULL, conn, false, sql);
+		pgfdw_report_error(NULL, conn, sql);
 	res = pgfdw_get_result(conn);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-		pgfdw_report_error(ERROR, res, conn, true, sql);
+		pgfdw_report_error(res, conn, sql);
 	PQclear(res);
 }
 
@@ -963,63 +968,73 @@ pgfdw_get_result(PGconn *conn)
 /*
  * Report an error we got from the remote server.
  *
- * elevel: error level to use (typically ERROR, but might be less)
- * res: PGresult containing the error
+ * Callers should use pgfdw_report_error() to throw an error, or use
+ * pgfdw_report() for lesser message levels.  (We make this distinction
+ * so that pgfdw_report_error() can be marked noreturn.)
+ *
+ * res: PGresult containing the error (might be NULL)
  * conn: connection we did the query on
- * clear: if true, PQclear the result (otherwise caller will handle it)
  * sql: NULL, or text of remote command we tried to execute
  *
+ * If "res" is not NULL, it'll be PQclear'ed here (unless we throw error,
+ * in which case memory context cleanup will clear it eventually).
+ *
  * Note: callers that choose not to throw ERROR for a remote error are
  * responsible for making sure that the associated ConnCacheEntry gets
  * marked with have_error = true.
  */
 void
-pgfdw_report_error(int elevel, PGresult *res, PGconn *conn,
-				   bool clear, const char *sql)
+pgfdw_report_error(PGresult *res, PGconn *conn, const char *sql)
 {
-	/* If requested, PGresult must be released before leaving this function. */
-	PG_TRY();
-	{
-		char	   *diag_sqlstate = PQresultErrorField(res, PG_DIAG_SQLSTATE);
-		char	   *message_primary = PQresultErrorField(res, PG_DIAG_MESSAGE_PRIMARY);
-		char	   *message_detail = PQresultErrorField(res, PG_DIAG_MESSAGE_DETAIL);
-		char	   *message_hint = PQresultErrorField(res, PG_DIAG_MESSAGE_HINT);
-		char	   *message_context = PQresultErrorField(res, PG_DIAG_CONTEXT);
-		int			sqlstate;
-
-		if (diag_sqlstate)
-			sqlstate = MAKE_SQLSTATE(diag_sqlstate[0],
-									 diag_sqlstate[1],
-									 diag_sqlstate[2],
-									 diag_sqlstate[3],
-									 diag_sqlstate[4]);
-		else
-			sqlstate = ERRCODE_CONNECTION_FAILURE;
+	pgfdw_report_internal(ERROR, res, conn, sql);
+	pg_unreachable();
+}
 
-		/*
-		 * If we don't get a message from the PGresult, try the PGconn.  This
-		 * is needed because for connection-level failures, PQgetResult may
-		 * just return NULL, not a PGresult at all.
-		 */
-		if (message_primary == NULL)
-			message_primary = pchomp(PQerrorMessage(conn));
-
-		ereport(elevel,
-				(errcode(sqlstate),
-				 (message_primary != NULL && message_primary[0] != '\0') ?
-				 errmsg_internal("%s", message_primary) :
-				 errmsg("could not obtain message string for remote error"),
-				 message_detail ? errdetail_internal("%s", message_detail) : 0,
-				 message_hint ? errhint("%s", message_hint) : 0,
-				 message_context ? errcontext("%s", message_context) : 0,
-				 sql ? errcontext("remote SQL command: %s", sql) : 0));
-	}
-	PG_FINALLY();
-	{
-		if (clear)
-			PQclear(res);
-	}
-	PG_END_TRY();
+void
+pgfdw_report(int elevel, PGresult *res, PGconn *conn, const char *sql)
+{
+	Assert(elevel < ERROR);		/* use pgfdw_report_error for that */
+	pgfdw_report_internal(elevel, res, conn, sql);
+}
+
+static void
+pgfdw_report_internal(int elevel, PGresult *res, PGconn *conn,
+					  const char *sql)
+{
+	char	   *diag_sqlstate = PQresultErrorField(res, PG_DIAG_SQLSTATE);
+	char	   *message_primary = PQresultErrorField(res, PG_DIAG_MESSAGE_PRIMARY);
+	char	   *message_detail = PQresultErrorField(res, PG_DIAG_MESSAGE_DETAIL);
+	char	   *message_hint = PQresultErrorField(res, PG_DIAG_MESSAGE_HINT);
+	char	   *message_context = PQresultErrorField(res, PG_DIAG_CONTEXT);
+	int			sqlstate;
+
+	if (diag_sqlstate)
+		sqlstate = MAKE_SQLSTATE(diag_sqlstate[0],
+								 diag_sqlstate[1],
+								 diag_sqlstate[2],
+								 diag_sqlstate[3],
+								 diag_sqlstate[4]);
+	else
+		sqlstate = ERRCODE_CONNECTION_FAILURE;
+
+	/*
+	 * If we don't get a message from the PGresult, try the PGconn.  This is
+	 * needed because for connection-level failures, PQgetResult may just
+	 * return NULL, not a PGresult at all.
+	 */
+	if (message_primary == NULL)
+		message_primary = pchomp(PQerrorMessage(conn));
+
+	ereport(elevel,
+			(errcode(sqlstate),
+			 (message_primary != NULL && message_primary[0] != '\0') ?
+			 errmsg_internal("%s", message_primary) :
+			 errmsg("could not obtain message string for remote error"),
+			 message_detail ? errdetail_internal("%s", message_detail) : 0,
+			 message_hint ? errhint("%s", message_hint) : 0,
+			 message_context ? errcontext("%s", message_context) : 0,
+			 sql ? errcontext("remote SQL command: %s", sql) : 0));
+	PQclear(res);
 }
 
 /*
@@ -1542,7 +1557,7 @@ pgfdw_exec_cleanup_query_begin(PGconn *conn, const char *query)
 	 */
 	if (!PQsendQuery(conn, query))
 	{
-		pgfdw_report_error(WARNING, NULL, conn, false, query);
+		pgfdw_report(WARNING, NULL, conn, query);
 		return false;
 	}
 
@@ -1567,7 +1582,7 @@ pgfdw_exec_cleanup_query_end(PGconn *conn, const char *query,
 	 */
 	if (consume_input && !PQconsumeInput(conn))
 	{
-		pgfdw_report_error(WARNING, NULL, conn, false, query);
+		pgfdw_report(WARNING, NULL, conn, query);
 		return false;
 	}
 
@@ -1579,7 +1594,7 @@ pgfdw_exec_cleanup_query_end(PGconn *conn, const char *query,
 					(errmsg("could not get query result due to timeout"),
 					 errcontext("remote SQL command: %s", query)));
 		else
-			pgfdw_report_error(WARNING, NULL, conn, false, query);
+			pgfdw_report(WARNING, NULL, conn, query);
 
 		return false;
 	}
@@ -1587,7 +1602,7 @@ pgfdw_exec_cleanup_query_end(PGconn *conn, const char *query,
 	/* Issue a warning if not successful. */
 	if (PQresultStatus(result) != PGRES_COMMAND_OK)
 	{
-		pgfdw_report_error(WARNING, result, conn, true, query);
+		pgfdw_report(WARNING, result, conn, query);
 		return ignore_errors;
 	}
 	PQclear(result);
@@ -1615,103 +1630,90 @@ pgfdw_get_cleanup_result(PGconn *conn, TimestampTz endtime,
 						 PGresult **result,
 						 bool *timed_out)
 {
-	volatile bool failed = false;
-	PGresult   *volatile last_res = NULL;
+	bool		failed = false;
+	PGresult   *last_res = NULL;
+	int			canceldelta = RETRY_CANCEL_TIMEOUT * 2;
 
 	*result = NULL;
 	*timed_out = false;
-
-	/* In what follows, do not leak any PGresults on an error. */
-	PG_TRY();
+	for (;;)
 	{
-		int			canceldelta = RETRY_CANCEL_TIMEOUT * 2;
+		PGresult   *res;
 
-		for (;;)
+		while (PQisBusy(conn))
 		{
-			PGresult   *res;
+			int			wc;
+			TimestampTz now = GetCurrentTimestamp();
+			long		cur_timeout;
 
-			while (PQisBusy(conn))
+			/* If timeout has expired, give up. */
+			if (now >= endtime)
 			{
-				int			wc;
-				TimestampTz now = GetCurrentTimestamp();
-				long		cur_timeout;
-
-				/* If timeout has expired, give up. */
-				if (now >= endtime)
-				{
-					*timed_out = true;
-					failed = true;
-					goto exit;
-				}
+				*timed_out = true;
+				failed = true;
+				goto exit;
+			}
 
-				/* If we need to re-issue the cancel request, do that. */
-				if (now >= retrycanceltime)
-				{
-					/* We ignore failure to issue the repeated request. */
-					(void) libpqsrv_cancel(conn, endtime);
+			/* If we need to re-issue the cancel request, do that. */
+			if (now >= retrycanceltime)
+			{
+				/* We ignore failure to issue the repeated request. */
+				(void) libpqsrv_cancel(conn, endtime);
 
-					/* Recompute "now" in case that took measurable time. */
-					now = GetCurrentTimestamp();
+				/* Recompute "now" in case that took measurable time. */
+				now = GetCurrentTimestamp();
 
-					/* Adjust re-cancel timeout in increasing steps. */
-					retrycanceltime = TimestampTzPlusMilliseconds(now,
-																  canceldelta);
-					canceldelta += canceldelta;
-				}
+				/* Adjust re-cancel timeout in increasing steps. */
+				retrycanceltime = TimestampTzPlusMilliseconds(now,
+															  canceldelta);
+				canceldelta += canceldelta;
+			}
 
-				/* If timeout has expired, give up, else get sleep time. */
-				cur_timeout = TimestampDifferenceMilliseconds(now,
-															  Min(endtime,
-																  retrycanceltime));
-				if (cur_timeout <= 0)
-				{
-					*timed_out = true;
-					failed = true;
-					goto exit;
-				}
+			/* If timeout has expired, give up, else get sleep time. */
+			cur_timeout = TimestampDifferenceMilliseconds(now,
+														  Min(endtime,
+															  retrycanceltime));
+			if (cur_timeout <= 0)
+			{
+				*timed_out = true;
+				failed = true;
+				goto exit;
+			}
 
-				/* first time, allocate or get the custom wait event */
-				if (pgfdw_we_cleanup_result == 0)
-					pgfdw_we_cleanup_result = WaitEventExtensionNew("PostgresFdwCleanupResult");
+			/* first time, allocate or get the custom wait event */
+			if (pgfdw_we_cleanup_result == 0)
+				pgfdw_we_cleanup_result = WaitEventExtensionNew("PostgresFdwCleanupResult");
 
-				/* Sleep until there's something to do */
-				wc = WaitLatchOrSocket(MyLatch,
-									   WL_LATCH_SET | WL_SOCKET_READABLE |
-									   WL_TIMEOUT | WL_EXIT_ON_PM_DEATH,
-									   PQsocket(conn),
-									   cur_timeout, pgfdw_we_cleanup_result);
-				ResetLatch(MyLatch);
+			/* Sleep until there's something to do */
+			wc = WaitLatchOrSocket(MyLatch,
+								   WL_LATCH_SET | WL_SOCKET_READABLE |
+								   WL_TIMEOUT | WL_EXIT_ON_PM_DEATH,
+								   PQsocket(conn),
+								   cur_timeout, pgfdw_we_cleanup_result);
+			ResetLatch(MyLatch);
 
-				CHECK_FOR_INTERRUPTS();
+			CHECK_FOR_INTERRUPTS();
 
-				/* Data available in socket? */
-				if (wc & WL_SOCKET_READABLE)
+			/* Data available in socket? */
+			if (wc & WL_SOCKET_READABLE)
+			{
+				if (!PQconsumeInput(conn))
 				{
-					if (!PQconsumeInput(conn))
-					{
-						/* connection trouble */
-						failed = true;
-						goto exit;
-					}
+					/* connection trouble */
+					failed = true;
+					goto exit;
 				}
 			}
+		}
 
-			res = PQgetResult(conn);
-			if (res == NULL)
-				break;			/* query is complete */
+		res = PQgetResult(conn);
+		if (res == NULL)
+			break;				/* query is complete */
 
-			PQclear(last_res);
-			last_res = res;
-		}
-exit:	;
-	}
-	PG_CATCH();
-	{
 		PQclear(last_res);
-		PG_RE_THROW();
+		last_res = res;
 	}
-	PG_END_TRY();
-
+exit:
 	if (failed)
 		PQclear(last_res);
 	else
diff --git a/contrib/postgres_fdw/deparse.c b/contrib/postgres_fdw/deparse.c
index d9970dd675336..e5b5e1a5f51a5 100644
--- a/contrib/postgres_fdw/deparse.c
+++ b/contrib/postgres_fdw/deparse.c
@@ -39,6 +39,7 @@
 #include "catalog/pg_aggregate.h"
 #include "catalog/pg_authid.h"
 #include "catalog/pg_collation.h"
+#include "catalog/pg_database.h"
 #include "catalog/pg_namespace.h"
 #include "catalog/pg_operator.h"
 #include "catalog/pg_opfamily.h"
@@ -160,6 +161,7 @@ static void deparseDistinctExpr(DistinctExpr *node, deparse_expr_cxt *context);
 static void deparseScalarArrayOpExpr(ScalarArrayOpExpr *node,
 									 deparse_expr_cxt *context);
 static void deparseRelabelType(RelabelType *node, deparse_expr_cxt *context);
+static void deparseArrayCoerceExpr(ArrayCoerceExpr *node, deparse_expr_cxt *context);
 static void deparseBoolExpr(BoolExpr *node, deparse_expr_cxt *context);
 static void deparseNullTest(NullTest *node, deparse_expr_cxt *context);
 static void deparseCaseExpr(CaseExpr *node, deparse_expr_cxt *context);
@@ -455,6 +457,11 @@ foreign_expr_walker(Node *node,
 											  AuthIdRelationId, fpinfo))
 								return false;
 							break;
+						case REGDATABASEOID:
+							if (!is_shippable(DatumGetObjectId(c->constvalue),
+											  DatabaseRelationId, fpinfo))
+								return false;
+							break;
 					}
 				}
 
@@ -696,6 +703,34 @@ foreign_expr_walker(Node *node,
 					state = FDW_COLLATE_UNSAFE;
 			}
 			break;
+		case T_ArrayCoerceExpr:
+			{
+				ArrayCoerceExpr *e = (ArrayCoerceExpr *) node;
+
+				/*
+				 * Recurse to input subexpression.
+				 */
+				if (!foreign_expr_walker((Node *) e->arg,
+										 glob_cxt, &inner_cxt, case_arg_cxt))
+					return false;
+
+				/*
+				 * T_ArrayCoerceExpr must not introduce a collation not
+				 * derived from an input foreign Var (same logic as for a
+				 * function).
+				 */
+				collation = e->resultcollid;
+				if (collation == InvalidOid)
+					state = FDW_COLLATE_NONE;
+				else if (inner_cxt.state == FDW_COLLATE_SAFE &&
+						 collation == inner_cxt.collation)
+					state = FDW_COLLATE_SAFE;
+				else if (collation == DEFAULT_COLLATION_OID)
+					state = FDW_COLLATE_NONE;
+				else
+					state = FDW_COLLATE_UNSAFE;
+			}
+			break;
 		case T_BoolExpr:
 			{
 				BoolExpr   *b = (BoolExpr *) node;
@@ -2913,6 +2948,9 @@ deparseExpr(Expr *node, deparse_expr_cxt *context)
 		case T_RelabelType:
 			deparseRelabelType((RelabelType *) node, context);
 			break;
+		case T_ArrayCoerceExpr:
+			deparseArrayCoerceExpr((ArrayCoerceExpr *) node, context);
+			break;
 		case T_BoolExpr:
 			deparseBoolExpr((BoolExpr *) node, context);
 			break;
@@ -3501,6 +3539,24 @@ deparseRelabelType(RelabelType *node, deparse_expr_cxt *context)
 										   node->resulttypmod));
 }
 
+/*
+ * Deparse an ArrayCoerceExpr (array-type conversion) node.
+ */
+static void
+deparseArrayCoerceExpr(ArrayCoerceExpr *node, deparse_expr_cxt *context)
+{
+	deparseExpr(node->arg, context);
+
+	/*
+	 * No difference how to deparse explicit cast, but if we omit implicit
+	 * cast in the query, it'll be more user-friendly
+	 */
+	if (node->coerceformat != COERCE_IMPLICIT_CAST)
+		appendStringInfo(context->buf, "::%s",
+						 deparse_type_name(node->resulttype,
+										   node->resulttypmod));
+}
+
 /*
  * Deparse a BoolExpr node.
  */
diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out
index 2185b42bb4f79..4b6e49a5d950d 100644
--- a/contrib/postgres_fdw/expected/postgres_fdw.out
+++ b/contrib/postgres_fdw/expected/postgres_fdw.out
@@ -710,12 +710,12 @@ EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE c1 = -c1;          -- Op
    Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE (("C 1" = (- "C 1")))
 (3 rows)
 
-EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE (c1 IS NOT NULL) IS DISTINCT FROM (c1 IS NOT NULL); -- DistinctExpr
-                                                                 QUERY PLAN                                                                 
---------------------------------------------------------------------------------------------------------------------------------------------
+EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE (c3 IS NOT NULL) IS DISTINCT FROM (c3 IS NOT NULL); -- DistinctExpr
+                                                              QUERY PLAN                                                              
+--------------------------------------------------------------------------------------------------------------------------------------
  Foreign Scan on public.ft1 t1
    Output: c1, c2, c3, c4, c5, c6, c7, c8
-   Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE ((("C 1" IS NOT NULL) IS DISTINCT FROM ("C 1" IS NOT NULL)))
+   Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE (((c3 IS NOT NULL) IS DISTINCT FROM (c3 IS NOT NULL)))
 (3 rows)
 
 EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE c1 = ANY(ARRAY[c2, 1, c1 + 0]); -- ScalarArrayOpExpr
@@ -1180,6 +1180,27 @@ SELECT * FROM ft1 WHERE CASE c3 COLLATE "C" WHEN c6 THEN true ELSE c3 < 'bar' EN
    Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1"
 (4 rows)
 
+-- Test array type conversion pushdown
+SET plan_cache_mode = force_generic_plan;
+PREPARE s(varchar[]) AS SELECT count(*) FROM ft2 WHERE c6 = ANY ($1);
+EXPLAIN (VERBOSE, COSTS OFF)
+EXECUTE s(ARRAY['1','2']);
+                                         QUERY PLAN                                          
+---------------------------------------------------------------------------------------------
+ Foreign Scan
+   Output: (count(*))
+   Relations: Aggregate on (public.ft2)
+   Remote SQL: SELECT count(*) FROM "S 1"."T 1" WHERE ((c6 = ANY ($1::character varying[])))
+(4 rows)
+
+EXECUTE s(ARRAY['1','2']);
+ count 
+-------
+   200
+(1 row)
+
+DEALLOCATE s;
+RESET plan_cache_mode;
 -- a regconfig constant referring to this text search configuration
 -- is initially unshippable
 CREATE TEXT SEARCH CONFIGURATION public.custom_search
diff --git a/contrib/postgres_fdw/meson.build b/contrib/postgres_fdw/meson.build
index 8b29be24deeb7..5c11bc6496fa8 100644
--- a/contrib/postgres_fdw/meson.build
+++ b/contrib/postgres_fdw/meson.build
@@ -39,7 +39,7 @@ tests += {
       'postgres_fdw',
       'query_cancel',
     ],
-    'regress_args': ['--dlpath', meson.build_root() / 'src/test/regress'],
+    'regress_args': ['--dlpath', meson.project_build_root() / 'src/test/regress'],
   },
   'tap': {
     'tests': [
diff --git a/contrib/postgres_fdw/option.c b/contrib/postgres_fdw/option.c
index c2f936640bca8..d6fa89bad9399 100644
--- a/contrib/postgres_fdw/option.c
+++ b/contrib/postgres_fdw/option.c
@@ -21,6 +21,7 @@
 #include "libpq/libpq-be.h"
 #include "postgres_fdw.h"
 #include "utils/guc.h"
+#include "utils/memutils.h"
 #include "utils/varlena.h"
 
 /*
@@ -39,12 +40,6 @@ typedef struct PgFdwOption
  */
 static PgFdwOption *postgres_fdw_options;
 
-/*
- * Valid options for libpq.
- * Allocated and filled in InitPgFdwOptions.
- */
-static PQconninfoOption *libpq_options;
-
 /*
  * GUC parameters
  */
@@ -239,6 +234,7 @@ static void
 InitPgFdwOptions(void)
 {
 	int			num_libpq_opts;
+	PQconninfoOption *libpq_options;
 	PQconninfoOption *lopt;
 	PgFdwOption *popt;
 
@@ -307,8 +303,8 @@ InitPgFdwOptions(void)
 	 * Get list of valid libpq options.
 	 *
 	 * To avoid unnecessary work, we get the list once and use it throughout
-	 * the lifetime of this backend process.  We don't need to care about
-	 * memory context issues, because PQconndefaults allocates with malloc.
+	 * the lifetime of this backend process.  Hence, we'll allocate it in
+	 * TopMemoryContext.
 	 */
 	libpq_options = PQconndefaults();
 	if (!libpq_options)			/* assume reason for failure is OOM */
@@ -325,19 +321,11 @@ InitPgFdwOptions(void)
 	/*
 	 * Construct an array which consists of all valid options for
 	 * postgres_fdw, by appending FDW-specific options to libpq options.
-	 *
-	 * We use plain malloc here to allocate postgres_fdw_options because it
-	 * lives as long as the backend process does.  Besides, keeping
-	 * libpq_options in memory allows us to avoid copying every keyword
-	 * string.
 	 */
 	postgres_fdw_options = (PgFdwOption *)
-		malloc(sizeof(PgFdwOption) * num_libpq_opts +
-			   sizeof(non_libpq_options));
-	if (postgres_fdw_options == NULL)
-		ereport(ERROR,
-				(errcode(ERRCODE_FDW_OUT_OF_MEMORY),
-				 errmsg("out of memory")));
+		MemoryContextAlloc(TopMemoryContext,
+						   sizeof(PgFdwOption) * num_libpq_opts +
+						   sizeof(non_libpq_options));
 
 	popt = postgres_fdw_options;
 	for (lopt = libpq_options; lopt->keyword; lopt++)
@@ -355,8 +343,8 @@ InitPgFdwOptions(void)
 		if (strncmp(lopt->keyword, "oauth_", strlen("oauth_")) == 0)
 			continue;
 
-		/* We don't have to copy keyword string, as described above. */
-		popt->keyword = lopt->keyword;
+		popt->keyword = MemoryContextStrdup(TopMemoryContext,
+											lopt->keyword);
 
 		/*
 		 * "user" and any secret options are allowed only on user mappings.
@@ -371,6 +359,9 @@ InitPgFdwOptions(void)
 		popt++;
 	}
 
+	/* Done with libpq's output structure. */
+	PQconninfoFree(libpq_options);
+
 	/* Append FDW-specific options and dummy terminator. */
 	memcpy(popt, non_libpq_options, sizeof(non_libpq_options));
 }
diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c
index 4283ce9f96252..456b267f70b5b 100644
--- a/contrib/postgres_fdw/postgres_fdw.c
+++ b/contrib/postgres_fdw/postgres_fdw.c
@@ -240,7 +240,6 @@ typedef struct PgFdwDirectModifyState
 	PGresult   *result;			/* result for query */
 	int			num_tuples;		/* # of result tuples */
 	int			next_tuple;		/* index of next one to return */
-	MemoryContextCallback result_cb;	/* ensures result will get freed */
 	Relation	resultRel;		/* relcache entry for the target relation */
 	AttrNumber *attnoMap;		/* array of attnums of input user columns */
 	AttrNumber	ctidAttno;		/* attnum of input ctid column */
@@ -1703,13 +1702,9 @@ postgresReScanForeignScan(ForeignScanState *node)
 		return;
 	}
 
-	/*
-	 * We don't use a PG_TRY block here, so be careful not to throw error
-	 * without releasing the PGresult.
-	 */
 	res = pgfdw_exec_query(fsstate->conn, sql, fsstate->conn_state);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-		pgfdw_report_error(ERROR, res, fsstate->conn, true, sql);
+		pgfdw_report_error(res, fsstate->conn, sql);
 	PQclear(res);
 
 	/* Now force a fresh FETCH. */
@@ -2671,17 +2666,6 @@ postgresBeginDirectModify(ForeignScanState *node, int eflags)
 	dmstate = (PgFdwDirectModifyState *) palloc0(sizeof(PgFdwDirectModifyState));
 	node->fdw_state = dmstate;
 
-	/*
-	 * We use a memory context callback to ensure that the dmstate's PGresult
-	 * (if any) will be released, even if the query fails somewhere that's
-	 * outside our control.  The callback is always armed for the duration of
-	 * the query; this relies on PQclear(NULL) being a no-op.
-	 */
-	dmstate->result_cb.func = (MemoryContextCallbackFunction) PQclear;
-	dmstate->result_cb.arg = NULL;
-	MemoryContextRegisterResetCallback(CurrentMemoryContext,
-									   &dmstate->result_cb);
-
 	/*
 	 * Identify which user to do the remote access as.  This should match what
 	 * ExecCheckPermissions() does.
@@ -2829,13 +2813,7 @@ postgresEndDirectModify(ForeignScanState *node)
 		return;
 
 	/* Release PGresult */
-	if (dmstate->result)
-	{
-		PQclear(dmstate->result);
-		dmstate->result = NULL;
-		/* ... and don't forget to disable the callback */
-		dmstate->result_cb.arg = NULL;
-	}
+	PQclear(dmstate->result);
 
 	/* Release remote connection */
 	ReleaseConnection(dmstate->conn);
@@ -3507,6 +3485,13 @@ estimate_path_cost_size(PlannerInfo *root,
 			{
 				Assert(foreignrel->reloptkind == RELOPT_UPPER_REL &&
 					   fpinfo->stage == UPPERREL_GROUP_AGG);
+
+				/*
+				 * We can only get here when this function is called from
+				 * add_foreign_ordered_paths() or add_foreign_final_paths();
+				 * in which cases, the passed-in fpextra should not be NULL.
+				 */
+				Assert(fpextra);
 				adjust_foreign_grouping_path_cost(root, pathkeys,
 												  retrieved_rows, width,
 												  fpextra->limit_tuples,
@@ -3619,41 +3604,32 @@ get_remote_estimate(const char *sql, PGconn *conn,
 					double *rows, int *width,
 					Cost *startup_cost, Cost *total_cost)
 {
-	PGresult   *volatile res = NULL;
-
-	/* PGresult must be released before leaving this function. */
-	PG_TRY();
-	{
-		char	   *line;
-		char	   *p;
-		int			n;
+	PGresult   *res;
+	char	   *line;
+	char	   *p;
+	int			n;
 
-		/*
-		 * Execute EXPLAIN remotely.
-		 */
-		res = pgfdw_exec_query(conn, sql, NULL);
-		if (PQresultStatus(res) != PGRES_TUPLES_OK)
-			pgfdw_report_error(ERROR, res, conn, false, sql);
+	/*
+	 * Execute EXPLAIN remotely.
+	 */
+	res = pgfdw_exec_query(conn, sql, NULL);
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+		pgfdw_report_error(res, conn, sql);
 
-		/*
-		 * Extract cost numbers for topmost plan node.  Note we search for a
-		 * left paren from the end of the line to avoid being confused by
-		 * other uses of parentheses.
-		 */
-		line = PQgetvalue(res, 0, 0);
-		p = strrchr(line, '(');
-		if (p == NULL)
-			elog(ERROR, "could not interpret EXPLAIN output: \"%s\"", line);
-		n = sscanf(p, "(cost=%lf..%lf rows=%lf width=%d)",
-				   startup_cost, total_cost, rows, width);
-		if (n != 4)
-			elog(ERROR, "could not interpret EXPLAIN output: \"%s\"", line);
-	}
-	PG_FINALLY();
-	{
-		PQclear(res);
-	}
-	PG_END_TRY();
+	/*
+	 * Extract cost numbers for topmost plan node.  Note we search for a left
+	 * paren from the end of the line to avoid being confused by other uses of
+	 * parentheses.
+	 */
+	line = PQgetvalue(res, 0, 0);
+	p = strrchr(line, '(');
+	if (p == NULL)
+		elog(ERROR, "could not interpret EXPLAIN output: \"%s\"", line);
+	n = sscanf(p, "(cost=%lf..%lf rows=%lf width=%d)",
+			   startup_cost, total_cost, rows, width);
+	if (n != 4)
+		elog(ERROR, "could not interpret EXPLAIN output: \"%s\"", line);
+	PQclear(res);
 }
 
 /*
@@ -3793,17 +3769,14 @@ create_cursor(ForeignScanState *node)
 	 */
 	if (!PQsendQueryParams(conn, buf.data, numParams,
 						   NULL, values, NULL, NULL, 0))
-		pgfdw_report_error(ERROR, NULL, conn, false, buf.data);
+		pgfdw_report_error(NULL, conn, buf.data);
 
 	/*
 	 * Get the result, and check for success.
-	 *
-	 * We don't use a PG_TRY block here, so be careful not to throw error
-	 * without releasing the PGresult.
 	 */
 	res = pgfdw_get_result(conn);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-		pgfdw_report_error(ERROR, res, conn, true, fsstate->query);
+		pgfdw_report_error(res, conn, fsstate->query);
 	PQclear(res);
 
 	/* Mark the cursor as created, and show no tuples have been retrieved */
@@ -3825,7 +3798,10 @@ static void
 fetch_more_data(ForeignScanState *node)
 {
 	PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state;
-	PGresult   *volatile res = NULL;
+	PGconn	   *conn = fsstate->conn;
+	PGresult   *res;
+	int			numrows;
+	int			i;
 	MemoryContext oldcontext;
 
 	/*
@@ -3836,74 +3812,63 @@ fetch_more_data(ForeignScanState *node)
 	MemoryContextReset(fsstate->batch_cxt);
 	oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt);
 
-	/* PGresult must be released before leaving this function. */
-	PG_TRY();
+	if (fsstate->async_capable)
 	{
-		PGconn	   *conn = fsstate->conn;
-		int			numrows;
-		int			i;
+		Assert(fsstate->conn_state->pendingAreq);
 
-		if (fsstate->async_capable)
-		{
-			Assert(fsstate->conn_state->pendingAreq);
+		/*
+		 * The query was already sent by an earlier call to
+		 * fetch_more_data_begin.  So now we just fetch the result.
+		 */
+		res = pgfdw_get_result(conn);
+		/* On error, report the original query, not the FETCH. */
+		if (PQresultStatus(res) != PGRES_TUPLES_OK)
+			pgfdw_report_error(res, conn, fsstate->query);
 
-			/*
-			 * The query was already sent by an earlier call to
-			 * fetch_more_data_begin.  So now we just fetch the result.
-			 */
-			res = pgfdw_get_result(conn);
-			/* On error, report the original query, not the FETCH. */
-			if (PQresultStatus(res) != PGRES_TUPLES_OK)
-				pgfdw_report_error(ERROR, res, conn, false, fsstate->query);
+		/* Reset per-connection state */
+		fsstate->conn_state->pendingAreq = NULL;
+	}
+	else
+	{
+		char		sql[64];
 
-			/* Reset per-connection state */
-			fsstate->conn_state->pendingAreq = NULL;
-		}
-		else
-		{
-			char		sql[64];
+		/* This is a regular synchronous fetch. */
+		snprintf(sql, sizeof(sql), "FETCH %d FROM c%u",
+				 fsstate->fetch_size, fsstate->cursor_number);
 
-			/* This is a regular synchronous fetch. */
-			snprintf(sql, sizeof(sql), "FETCH %d FROM c%u",
-					 fsstate->fetch_size, fsstate->cursor_number);
+		res = pgfdw_exec_query(conn, sql, fsstate->conn_state);
+		/* On error, report the original query, not the FETCH. */
+		if (PQresultStatus(res) != PGRES_TUPLES_OK)
+			pgfdw_report_error(res, conn, fsstate->query);
+	}
 
-			res = pgfdw_exec_query(conn, sql, fsstate->conn_state);
-			/* On error, report the original query, not the FETCH. */
-			if (PQresultStatus(res) != PGRES_TUPLES_OK)
-				pgfdw_report_error(ERROR, res, conn, false, fsstate->query);
-		}
+	/* Convert the data into HeapTuples */
+	numrows = PQntuples(res);
+	fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple));
+	fsstate->num_tuples = numrows;
+	fsstate->next_tuple = 0;
 
-		/* Convert the data into HeapTuples */
-		numrows = PQntuples(res);
-		fsstate->tuples = (HeapTuple *) palloc0(numrows * sizeof(HeapTuple));
-		fsstate->num_tuples = numrows;
-		fsstate->next_tuple = 0;
+	for (i = 0; i < numrows; i++)
+	{
+		Assert(IsA(node->ss.ps.plan, ForeignScan));
 
-		for (i = 0; i < numrows; i++)
-		{
-			Assert(IsA(node->ss.ps.plan, ForeignScan));
-
-			fsstate->tuples[i] =
-				make_tuple_from_result_row(res, i,
-										   fsstate->rel,
-										   fsstate->attinmeta,
-										   fsstate->retrieved_attrs,
-										   node,
-										   fsstate->temp_cxt);
-		}
+		fsstate->tuples[i] =
+			make_tuple_from_result_row(res, i,
+									   fsstate->rel,
+									   fsstate->attinmeta,
+									   fsstate->retrieved_attrs,
+									   node,
+									   fsstate->temp_cxt);
+	}
 
-		/* Update fetch_ct_2 */
-		if (fsstate->fetch_ct_2 < 2)
-			fsstate->fetch_ct_2++;
+	/* Update fetch_ct_2 */
+	if (fsstate->fetch_ct_2 < 2)
+		fsstate->fetch_ct_2++;
 
-		/* Must be EOF if we didn't get as many tuples as we asked for. */
-		fsstate->eof_reached = (numrows < fsstate->fetch_size);
-	}
-	PG_FINALLY();
-	{
-		PQclear(res);
-	}
-	PG_END_TRY();
+	/* Must be EOF if we didn't get as many tuples as we asked for. */
+	fsstate->eof_reached = (numrows < fsstate->fetch_size);
+
+	PQclear(res);
 
 	MemoryContextSwitchTo(oldcontext);
 }
@@ -3977,14 +3942,9 @@ close_cursor(PGconn *conn, unsigned int cursor_number,
 	PGresult   *res;
 
 	snprintf(sql, sizeof(sql), "CLOSE c%u", cursor_number);
-
-	/*
-	 * We don't use a PG_TRY block here, so be careful not to throw error
-	 * without releasing the PGresult.
-	 */
 	res = pgfdw_exec_query(conn, sql, conn_state);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-		pgfdw_report_error(ERROR, res, conn, true, sql);
+		pgfdw_report_error(res, conn, sql);
 	PQclear(res);
 }
 
@@ -4192,18 +4152,15 @@ execute_foreign_modify(EState *estate,
 							 NULL,
 							 NULL,
 							 0))
-		pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query);
+		pgfdw_report_error(NULL, fmstate->conn, fmstate->query);
 
 	/*
 	 * Get the result, and check for success.
-	 *
-	 * We don't use a PG_TRY block here, so be careful not to throw error
-	 * without releasing the PGresult.
 	 */
 	res = pgfdw_get_result(fmstate->conn);
 	if (PQresultStatus(res) !=
 		(fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK))
-		pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query);
+		pgfdw_report_error(res, fmstate->conn, fmstate->query);
 
 	/* Check number of rows affected, and fetch RETURNING tuple if any */
 	if (fmstate->has_returning)
@@ -4262,17 +4219,14 @@ prepare_foreign_modify(PgFdwModifyState *fmstate)
 					   fmstate->query,
 					   0,
 					   NULL))
-		pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query);
+		pgfdw_report_error(NULL, fmstate->conn, fmstate->query);
 
 	/*
 	 * Get the result, and check for success.
-	 *
-	 * We don't use a PG_TRY block here, so be careful not to throw error
-	 * without releasing the PGresult.
 	 */
 	res = pgfdw_get_result(fmstate->conn);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-		pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query);
+		pgfdw_report_error(res, fmstate->conn, fmstate->query);
 	PQclear(res);
 
 	/* This action shows that the prepare has been done. */
@@ -4363,37 +4317,25 @@ convert_prep_stmt_params(PgFdwModifyState *fmstate,
 /*
  * store_returning_result
  *		Store the result of a RETURNING clause
- *
- * On error, be sure to release the PGresult on the way out.  Callers do not
- * have PG_TRY blocks to ensure this happens.
  */
 static void
 store_returning_result(PgFdwModifyState *fmstate,
 					   TupleTableSlot *slot, PGresult *res)
 {
-	PG_TRY();
-	{
-		HeapTuple	newtup;
+	HeapTuple	newtup;
 
-		newtup = make_tuple_from_result_row(res, 0,
-											fmstate->rel,
-											fmstate->attinmeta,
-											fmstate->retrieved_attrs,
-											NULL,
-											fmstate->temp_cxt);
+	newtup = make_tuple_from_result_row(res, 0,
+										fmstate->rel,
+										fmstate->attinmeta,
+										fmstate->retrieved_attrs,
+										NULL,
+										fmstate->temp_cxt);
 
-		/*
-		 * The returning slot will not necessarily be suitable to store
-		 * heaptuples directly, so allow for conversion.
-		 */
-		ExecForceStoreHeapTuple(newtup, slot, true);
-	}
-	PG_CATCH();
-	{
-		PQclear(res);
-		PG_RE_THROW();
-	}
-	PG_END_TRY();
+	/*
+	 * The returning slot will not necessarily be suitable to store heaptuples
+	 * directly, so allow for conversion.
+	 */
+	ExecForceStoreHeapTuple(newtup, slot, true);
 }
 
 /*
@@ -4429,14 +4371,9 @@ deallocate_query(PgFdwModifyState *fmstate)
 		return;
 
 	snprintf(sql, sizeof(sql), "DEALLOCATE %s", fmstate->p_name);
-
-	/*
-	 * We don't use a PG_TRY block here, so be careful not to throw error
-	 * without releasing the PGresult.
-	 */
 	res = pgfdw_exec_query(fmstate->conn, sql, fmstate->conn_state);
 	if (PQresultStatus(res) != PGRES_COMMAND_OK)
-		pgfdw_report_error(ERROR, res, fmstate->conn, true, sql);
+		pgfdw_report_error(res, fmstate->conn, sql);
 	PQclear(res);
 	pfree(fmstate->p_name);
 	fmstate->p_name = NULL;
@@ -4604,24 +4541,24 @@ execute_dml_stmt(ForeignScanState *node)
 	 */
 	if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams,
 						   NULL, values, NULL, NULL, 0))
-		pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query);
+		pgfdw_report_error(NULL, dmstate->conn, dmstate->query);
 
 	/*
 	 * Get the result, and check for success.
-	 *
-	 * We use a memory context callback to ensure that the PGresult will be
-	 * released, even if the query fails somewhere that's outside our control.
-	 * The callback is already registered, just need to fill in its arg.
 	 */
-	Assert(dmstate->result == NULL);
 	dmstate->result = pgfdw_get_result(dmstate->conn);
-	dmstate->result_cb.arg = dmstate->result;
-
 	if (PQresultStatus(dmstate->result) !=
 		(dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK))
-		pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, false,
+		pgfdw_report_error(dmstate->result, dmstate->conn,
 						   dmstate->query);
 
+	/*
+	 * The result potentially needs to survive across multiple executor row
+	 * cycles, so move it to the context where the dmstate is.
+	 */
+	dmstate->result = libpqsrv_PGresultSetParent(dmstate->result,
+												 GetMemoryChunkContext(dmstate));
+
 	/* Get the number of rows affected. */
 	if (dmstate->has_returning)
 		dmstate->num_tuples = PQntuples(dmstate->result);
@@ -4958,7 +4895,7 @@ postgresAnalyzeForeignTable(Relation relation,
 	UserMapping *user;
 	PGconn	   *conn;
 	StringInfoData sql;
-	PGresult   *volatile res = NULL;
+	PGresult   *res;
 
 	/* Return the row-analysis function pointer */
 	*func = postgresAcquireSampleRowsFunc;
@@ -4984,22 +4921,14 @@ postgresAnalyzeForeignTable(Relation relation,
 	initStringInfo(&sql);
 	deparseAnalyzeSizeSql(&sql, relation);
 
-	/* In what follows, do not risk leaking any PGresults. */
-	PG_TRY();
-	{
-		res = pgfdw_exec_query(conn, sql.data, NULL);
-		if (PQresultStatus(res) != PGRES_TUPLES_OK)
-			pgfdw_report_error(ERROR, res, conn, false, sql.data);
+	res = pgfdw_exec_query(conn, sql.data, NULL);
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+		pgfdw_report_error(res, conn, sql.data);
 
-		if (PQntuples(res) != 1 || PQnfields(res) != 1)
-			elog(ERROR, "unexpected result from deparseAnalyzeSizeSql query");
-		*totalpages = strtoul(PQgetvalue(res, 0, 0), NULL, 10);
-	}
-	PG_FINALLY();
-	{
-		PQclear(res);
-	}
-	PG_END_TRY();
+	if (PQntuples(res) != 1 || PQnfields(res) != 1)
+		elog(ERROR, "unexpected result from deparseAnalyzeSizeSql query");
+	*totalpages = strtoul(PQgetvalue(res, 0, 0), NULL, 10);
+	PQclear(res);
 
 	ReleaseConnection(conn);
 
@@ -5020,9 +4949,9 @@ postgresGetAnalyzeInfoForForeignTable(Relation relation, bool *can_tablesample)
 	UserMapping *user;
 	PGconn	   *conn;
 	StringInfoData sql;
-	PGresult   *volatile res = NULL;
-	volatile double reltuples = -1;
-	volatile char relkind = 0;
+	PGresult   *res;
+	double		reltuples;
+	char		relkind;
 
 	/* assume the remote relation does not support TABLESAMPLE */
 	*can_tablesample = false;
@@ -5041,24 +4970,15 @@ postgresGetAnalyzeInfoForForeignTable(Relation relation, bool *can_tablesample)
 	initStringInfo(&sql);
 	deparseAnalyzeInfoSql(&sql, relation);
 
-	/* In what follows, do not risk leaking any PGresults. */
-	PG_TRY();
-	{
-		res = pgfdw_exec_query(conn, sql.data, NULL);
-		if (PQresultStatus(res) != PGRES_TUPLES_OK)
-			pgfdw_report_error(ERROR, res, conn, false, sql.data);
+	res = pgfdw_exec_query(conn, sql.data, NULL);
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+		pgfdw_report_error(res, conn, sql.data);
 
-		if (PQntuples(res) != 1 || PQnfields(res) != 2)
-			elog(ERROR, "unexpected result from deparseAnalyzeInfoSql query");
-		reltuples = strtod(PQgetvalue(res, 0, 0), NULL);
-		relkind = *(PQgetvalue(res, 0, 1));
-	}
-	PG_FINALLY();
-	{
-		if (res)
-			PQclear(res);
-	}
-	PG_END_TRY();
+	if (PQntuples(res) != 1 || PQnfields(res) != 2)
+		elog(ERROR, "unexpected result from deparseAnalyzeInfoSql query");
+	reltuples = strtod(PQgetvalue(res, 0, 0), NULL);
+	relkind = *(PQgetvalue(res, 0, 1));
+	PQclear(res);
 
 	ReleaseConnection(conn);
 
@@ -5098,10 +5018,12 @@ postgresAcquireSampleRowsFunc(Relation relation, int elevel,
 	int			server_version_num;
 	PgFdwSamplingMethod method = ANALYZE_SAMPLE_AUTO;	/* auto is default */
 	double		sample_frac = -1.0;
-	double		reltuples;
+	double		reltuples = -1.0;
 	unsigned int cursor_number;
 	StringInfoData sql;
-	PGresult   *volatile res = NULL;
+	PGresult   *res;
+	char		fetch_sql[64];
+	int			fetch_size;
 	ListCell   *lc;
 
 	/* Initialize workspace state */
@@ -5278,91 +5200,76 @@ postgresAcquireSampleRowsFunc(Relation relation, int elevel,
 
 	deparseAnalyzeSql(&sql, relation, method, sample_frac, &astate.retrieved_attrs);
 
-	/* In what follows, do not risk leaking any PGresults. */
-	PG_TRY();
-	{
-		char		fetch_sql[64];
-		int			fetch_size;
-
-		res = pgfdw_exec_query(conn, sql.data, NULL);
-		if (PQresultStatus(res) != PGRES_COMMAND_OK)
-			pgfdw_report_error(ERROR, res, conn, false, sql.data);
-		PQclear(res);
-		res = NULL;
+	res = pgfdw_exec_query(conn, sql.data, NULL);
+	if (PQresultStatus(res) != PGRES_COMMAND_OK)
+		pgfdw_report_error(res, conn, sql.data);
+	PQclear(res);
 
-		/*
-		 * Determine the fetch size.  The default is arbitrary, but shouldn't
-		 * be enormous.
-		 */
-		fetch_size = 100;
-		foreach(lc, server->options)
-		{
-			DefElem    *def = (DefElem *) lfirst(lc);
+	/*
+	 * Determine the fetch size.  The default is arbitrary, but shouldn't be
+	 * enormous.
+	 */
+	fetch_size = 100;
+	foreach(lc, server->options)
+	{
+		DefElem    *def = (DefElem *) lfirst(lc);
 
-			if (strcmp(def->defname, "fetch_size") == 0)
-			{
-				(void) parse_int(defGetString(def), &fetch_size, 0, NULL);
-				break;
-			}
-		}
-		foreach(lc, table->options)
+		if (strcmp(def->defname, "fetch_size") == 0)
 		{
-			DefElem    *def = (DefElem *) lfirst(lc);
-
-			if (strcmp(def->defname, "fetch_size") == 0)
-			{
-				(void) parse_int(defGetString(def), &fetch_size, 0, NULL);
-				break;
-			}
+			(void) parse_int(defGetString(def), &fetch_size, 0, NULL);
+			break;
 		}
+	}
+	foreach(lc, table->options)
+	{
+		DefElem    *def = (DefElem *) lfirst(lc);
 
-		/* Construct command to fetch rows from remote. */
-		snprintf(fetch_sql, sizeof(fetch_sql), "FETCH %d FROM c%u",
-				 fetch_size, cursor_number);
-
-		/* Retrieve and process rows a batch at a time. */
-		for (;;)
+		if (strcmp(def->defname, "fetch_size") == 0)
 		{
-			int			numrows;
-			int			i;
+			(void) parse_int(defGetString(def), &fetch_size, 0, NULL);
+			break;
+		}
+	}
 
-			/* Allow users to cancel long query */
-			CHECK_FOR_INTERRUPTS();
+	/* Construct command to fetch rows from remote. */
+	snprintf(fetch_sql, sizeof(fetch_sql), "FETCH %d FROM c%u",
+			 fetch_size, cursor_number);
 
-			/*
-			 * XXX possible future improvement: if rowstoskip is large, we
-			 * could issue a MOVE rather than physically fetching the rows,
-			 * then just adjust rowstoskip and samplerows appropriately.
-			 */
+	/* Retrieve and process rows a batch at a time. */
+	for (;;)
+	{
+		int			numrows;
+		int			i;
 
-			/* Fetch some rows */
-			res = pgfdw_exec_query(conn, fetch_sql, NULL);
-			/* On error, report the original query, not the FETCH. */
-			if (PQresultStatus(res) != PGRES_TUPLES_OK)
-				pgfdw_report_error(ERROR, res, conn, false, sql.data);
+		/* Allow users to cancel long query */
+		CHECK_FOR_INTERRUPTS();
 
-			/* Process whatever we got. */
-			numrows = PQntuples(res);
-			for (i = 0; i < numrows; i++)
-				analyze_row_processor(res, i, &astate);
+		/*
+		 * XXX possible future improvement: if rowstoskip is large, we could
+		 * issue a MOVE rather than physically fetching the rows, then just
+		 * adjust rowstoskip and samplerows appropriately.
+		 */
 
-			PQclear(res);
-			res = NULL;
+		/* Fetch some rows */
+		res = pgfdw_exec_query(conn, fetch_sql, NULL);
+		/* On error, report the original query, not the FETCH. */
+		if (PQresultStatus(res) != PGRES_TUPLES_OK)
+			pgfdw_report_error(res, conn, sql.data);
 
-			/* Must be EOF if we didn't get all the rows requested. */
-			if (numrows < fetch_size)
-				break;
-		}
+		/* Process whatever we got. */
+		numrows = PQntuples(res);
+		for (i = 0; i < numrows; i++)
+			analyze_row_processor(res, i, &astate);
 
-		/* Close the cursor, just to be tidy. */
-		close_cursor(conn, cursor_number, NULL);
-	}
-	PG_CATCH();
-	{
 		PQclear(res);
-		PG_RE_THROW();
+
+		/* Must be EOF if we didn't get all the rows requested. */
+		if (numrows < fetch_size)
+			break;
 	}
-	PG_END_TRY();
+
+	/* Close the cursor, just to be tidy. */
+	close_cursor(conn, cursor_number, NULL);
 
 	ReleaseConnection(conn);
 
@@ -5474,7 +5381,7 @@ postgresImportForeignSchema(ImportForeignSchemaStmt *stmt, Oid serverOid)
 	UserMapping *mapping;
 	PGconn	   *conn;
 	StringInfoData buf;
-	PGresult   *volatile res = NULL;
+	PGresult   *res;
 	int			numrows,
 				i;
 	ListCell   *lc;
@@ -5513,243 +5420,231 @@ postgresImportForeignSchema(ImportForeignSchemaStmt *stmt, Oid serverOid)
 	/* Create workspace for strings */
 	initStringInfo(&buf);
 
-	/* In what follows, do not risk leaking any PGresults. */
-	PG_TRY();
-	{
-		/* Check that the schema really exists */
-		appendStringInfoString(&buf, "SELECT 1 FROM pg_catalog.pg_namespace WHERE nspname = ");
-		deparseStringLiteral(&buf, stmt->remote_schema);
+	/* Check that the schema really exists */
+	appendStringInfoString(&buf, "SELECT 1 FROM pg_catalog.pg_namespace WHERE nspname = ");
+	deparseStringLiteral(&buf, stmt->remote_schema);
 
-		res = pgfdw_exec_query(conn, buf.data, NULL);
-		if (PQresultStatus(res) != PGRES_TUPLES_OK)
-			pgfdw_report_error(ERROR, res, conn, false, buf.data);
+	res = pgfdw_exec_query(conn, buf.data, NULL);
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+		pgfdw_report_error(res, conn, buf.data);
 
-		if (PQntuples(res) != 1)
-			ereport(ERROR,
-					(errcode(ERRCODE_FDW_SCHEMA_NOT_FOUND),
-					 errmsg("schema \"%s\" is not present on foreign server \"%s\"",
-							stmt->remote_schema, server->servername)));
+	if (PQntuples(res) != 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_FDW_SCHEMA_NOT_FOUND),
+				 errmsg("schema \"%s\" is not present on foreign server \"%s\"",
+						stmt->remote_schema, server->servername)));
 
-		PQclear(res);
-		res = NULL;
-		resetStringInfo(&buf);
+	PQclear(res);
+	resetStringInfo(&buf);
 
-		/*
-		 * Fetch all table data from this schema, possibly restricted by
-		 * EXCEPT or LIMIT TO.  (We don't actually need to pay any attention
-		 * to EXCEPT/LIMIT TO here, because the core code will filter the
-		 * statements we return according to those lists anyway.  But it
-		 * should save a few cycles to not process excluded tables in the
-		 * first place.)
-		 *
-		 * Import table data for partitions only when they are explicitly
-		 * specified in LIMIT TO clause. Otherwise ignore them and only
-		 * include the definitions of the root partitioned tables to allow
-		 * access to the complete remote data set locally in the schema
-		 * imported.
-		 *
-		 * Note: because we run the connection with search_path restricted to
-		 * pg_catalog, the format_type() and pg_get_expr() outputs will always
-		 * include a schema name for types/functions in other schemas, which
-		 * is what we want.
-		 */
+	/*
+	 * Fetch all table data from this schema, possibly restricted by EXCEPT or
+	 * LIMIT TO.  (We don't actually need to pay any attention to EXCEPT/LIMIT
+	 * TO here, because the core code will filter the statements we return
+	 * according to those lists anyway.  But it should save a few cycles to
+	 * not process excluded tables in the first place.)
+	 *
+	 * Import table data for partitions only when they are explicitly
+	 * specified in LIMIT TO clause. Otherwise ignore them and only include
+	 * the definitions of the root partitioned tables to allow access to the
+	 * complete remote data set locally in the schema imported.
+	 *
+	 * Note: because we run the connection with search_path restricted to
+	 * pg_catalog, the format_type() and pg_get_expr() outputs will always
+	 * include a schema name for types/functions in other schemas, which is
+	 * what we want.
+	 */
+	appendStringInfoString(&buf,
+						   "SELECT relname, "
+						   "  attname, "
+						   "  format_type(atttypid, atttypmod), "
+						   "  attnotnull, "
+						   "  pg_get_expr(adbin, adrelid), ");
+
+	/* Generated columns are supported since Postgres 12 */
+	if (PQserverVersion(conn) >= 120000)
 		appendStringInfoString(&buf,
-							   "SELECT relname, "
-							   "  attname, "
-							   "  format_type(atttypid, atttypmod), "
-							   "  attnotnull, "
-							   "  pg_get_expr(adbin, adrelid), ");
-
-		/* Generated columns are supported since Postgres 12 */
-		if (PQserverVersion(conn) >= 120000)
-			appendStringInfoString(&buf,
-								   "  attgenerated, ");
-		else
-			appendStringInfoString(&buf,
-								   "  NULL, ");
-
-		if (import_collate)
-			appendStringInfoString(&buf,
-								   "  collname, "
-								   "  collnsp.nspname ");
-		else
-			appendStringInfoString(&buf,
-								   "  NULL, NULL ");
-
+							   "  attgenerated, ");
+	else
 		appendStringInfoString(&buf,
-							   "FROM pg_class c "
-							   "  JOIN pg_namespace n ON "
-							   "    relnamespace = n.oid "
-							   "  LEFT JOIN pg_attribute a ON "
-							   "    attrelid = c.oid AND attnum > 0 "
-							   "      AND NOT attisdropped "
-							   "  LEFT JOIN pg_attrdef ad ON "
-							   "    adrelid = c.oid AND adnum = attnum ");
-
-		if (import_collate)
-			appendStringInfoString(&buf,
-								   "  LEFT JOIN pg_collation coll ON "
-								   "    coll.oid = attcollation "
-								   "  LEFT JOIN pg_namespace collnsp ON "
-								   "    collnsp.oid = collnamespace ");
+							   "  NULL, ");
 
+	if (import_collate)
 		appendStringInfoString(&buf,
-							   "WHERE c.relkind IN ("
-							   CppAsString2(RELKIND_RELATION) ","
-							   CppAsString2(RELKIND_VIEW) ","
-							   CppAsString2(RELKIND_FOREIGN_TABLE) ","
-							   CppAsString2(RELKIND_MATVIEW) ","
-							   CppAsString2(RELKIND_PARTITIONED_TABLE) ") "
-							   "  AND n.nspname = ");
-		deparseStringLiteral(&buf, stmt->remote_schema);
-
-		/* Partitions are supported since Postgres 10 */
-		if (PQserverVersion(conn) >= 100000 &&
-			stmt->list_type != FDW_IMPORT_SCHEMA_LIMIT_TO)
-			appendStringInfoString(&buf, " AND NOT c.relispartition ");
-
-		/* Apply restrictions for LIMIT TO and EXCEPT */
-		if (stmt->list_type == FDW_IMPORT_SCHEMA_LIMIT_TO ||
-			stmt->list_type == FDW_IMPORT_SCHEMA_EXCEPT)
+							   "  collname, "
+							   "  collnsp.nspname ");
+	else
+		appendStringInfoString(&buf,
+							   "  NULL, NULL ");
+
+	appendStringInfoString(&buf,
+						   "FROM pg_class c "
+						   "  JOIN pg_namespace n ON "
+						   "    relnamespace = n.oid "
+						   "  LEFT JOIN pg_attribute a ON "
+						   "    attrelid = c.oid AND attnum > 0 "
+						   "      AND NOT attisdropped "
+						   "  LEFT JOIN pg_attrdef ad ON "
+						   "    adrelid = c.oid AND adnum = attnum ");
+
+	if (import_collate)
+		appendStringInfoString(&buf,
+							   "  LEFT JOIN pg_collation coll ON "
+							   "    coll.oid = attcollation "
+							   "  LEFT JOIN pg_namespace collnsp ON "
+							   "    collnsp.oid = collnamespace ");
+
+	appendStringInfoString(&buf,
+						   "WHERE c.relkind IN ("
+						   CppAsString2(RELKIND_RELATION) ","
+						   CppAsString2(RELKIND_VIEW) ","
+						   CppAsString2(RELKIND_FOREIGN_TABLE) ","
+						   CppAsString2(RELKIND_MATVIEW) ","
+						   CppAsString2(RELKIND_PARTITIONED_TABLE) ") "
+						   "  AND n.nspname = ");
+	deparseStringLiteral(&buf, stmt->remote_schema);
+
+	/* Partitions are supported since Postgres 10 */
+	if (PQserverVersion(conn) >= 100000 &&
+		stmt->list_type != FDW_IMPORT_SCHEMA_LIMIT_TO)
+		appendStringInfoString(&buf, " AND NOT c.relispartition ");
+
+	/* Apply restrictions for LIMIT TO and EXCEPT */
+	if (stmt->list_type == FDW_IMPORT_SCHEMA_LIMIT_TO ||
+		stmt->list_type == FDW_IMPORT_SCHEMA_EXCEPT)
+	{
+		bool		first_item = true;
+
+		appendStringInfoString(&buf, " AND c.relname ");
+		if (stmt->list_type == FDW_IMPORT_SCHEMA_EXCEPT)
+			appendStringInfoString(&buf, "NOT ");
+		appendStringInfoString(&buf, "IN (");
+
+		/* Append list of table names within IN clause */
+		foreach(lc, stmt->table_list)
 		{
-			bool		first_item = true;
+			RangeVar   *rv = (RangeVar *) lfirst(lc);
 
-			appendStringInfoString(&buf, " AND c.relname ");
-			if (stmt->list_type == FDW_IMPORT_SCHEMA_EXCEPT)
-				appendStringInfoString(&buf, "NOT ");
-			appendStringInfoString(&buf, "IN (");
+			if (first_item)
+				first_item = false;
+			else
+				appendStringInfoString(&buf, ", ");
+			deparseStringLiteral(&buf, rv->relname);
+		}
+		appendStringInfoChar(&buf, ')');
+	}
 
-			/* Append list of table names within IN clause */
-			foreach(lc, stmt->table_list)
-			{
-				RangeVar   *rv = (RangeVar *) lfirst(lc);
+	/* Append ORDER BY at the end of query to ensure output ordering */
+	appendStringInfoString(&buf, " ORDER BY c.relname, a.attnum");
 
-				if (first_item)
-					first_item = false;
-				else
-					appendStringInfoString(&buf, ", ");
-				deparseStringLiteral(&buf, rv->relname);
-			}
-			appendStringInfoChar(&buf, ')');
-		}
+	/* Fetch the data */
+	res = pgfdw_exec_query(conn, buf.data, NULL);
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+		pgfdw_report_error(res, conn, buf.data);
 
-		/* Append ORDER BY at the end of query to ensure output ordering */
-		appendStringInfoString(&buf, " ORDER BY c.relname, a.attnum");
+	/* Process results */
+	numrows = PQntuples(res);
+	/* note: incrementation of i happens in inner loop's while() test */
+	for (i = 0; i < numrows;)
+	{
+		char	   *tablename = PQgetvalue(res, i, 0);
+		bool		first_item = true;
 
-		/* Fetch the data */
-		res = pgfdw_exec_query(conn, buf.data, NULL);
-		if (PQresultStatus(res) != PGRES_TUPLES_OK)
-			pgfdw_report_error(ERROR, res, conn, false, buf.data);
+		resetStringInfo(&buf);
+		appendStringInfo(&buf, "CREATE FOREIGN TABLE %s (\n",
+						 quote_identifier(tablename));
 
-		/* Process results */
-		numrows = PQntuples(res);
-		/* note: incrementation of i happens in inner loop's while() test */
-		for (i = 0; i < numrows;)
+		/* Scan all rows for this table */
+		do
 		{
-			char	   *tablename = PQgetvalue(res, i, 0);
-			bool		first_item = true;
+			char	   *attname;
+			char	   *typename;
+			char	   *attnotnull;
+			char	   *attgenerated;
+			char	   *attdefault;
+			char	   *collname;
+			char	   *collnamespace;
+
+			/* If table has no columns, we'll see nulls here */
+			if (PQgetisnull(res, i, 1))
+				continue;
 
-			resetStringInfo(&buf);
-			appendStringInfo(&buf, "CREATE FOREIGN TABLE %s (\n",
-							 quote_identifier(tablename));
+			attname = PQgetvalue(res, i, 1);
+			typename = PQgetvalue(res, i, 2);
+			attnotnull = PQgetvalue(res, i, 3);
+			attdefault = PQgetisnull(res, i, 4) ? NULL :
+				PQgetvalue(res, i, 4);
+			attgenerated = PQgetisnull(res, i, 5) ? NULL :
+				PQgetvalue(res, i, 5);
+			collname = PQgetisnull(res, i, 6) ? NULL :
+				PQgetvalue(res, i, 6);
+			collnamespace = PQgetisnull(res, i, 7) ? NULL :
+				PQgetvalue(res, i, 7);
+
+			if (first_item)
+				first_item = false;
+			else
+				appendStringInfoString(&buf, ",\n");
 
-			/* Scan all rows for this table */
-			do
-			{
-				char	   *attname;
-				char	   *typename;
-				char	   *attnotnull;
-				char	   *attgenerated;
-				char	   *attdefault;
-				char	   *collname;
-				char	   *collnamespace;
-
-				/* If table has no columns, we'll see nulls here */
-				if (PQgetisnull(res, i, 1))
-					continue;
+			/* Print column name and type */
+			appendStringInfo(&buf, "  %s %s",
+							 quote_identifier(attname),
+							 typename);
 
-				attname = PQgetvalue(res, i, 1);
-				typename = PQgetvalue(res, i, 2);
-				attnotnull = PQgetvalue(res, i, 3);
-				attdefault = PQgetisnull(res, i, 4) ? NULL :
-					PQgetvalue(res, i, 4);
-				attgenerated = PQgetisnull(res, i, 5) ? NULL :
-					PQgetvalue(res, i, 5);
-				collname = PQgetisnull(res, i, 6) ? NULL :
-					PQgetvalue(res, i, 6);
-				collnamespace = PQgetisnull(res, i, 7) ? NULL :
-					PQgetvalue(res, i, 7);
-
-				if (first_item)
-					first_item = false;
-				else
-					appendStringInfoString(&buf, ",\n");
+			/*
+			 * Add column_name option so that renaming the foreign table's
+			 * column doesn't break the association to the underlying column.
+			 */
+			appendStringInfoString(&buf, " OPTIONS (column_name ");
+			deparseStringLiteral(&buf, attname);
+			appendStringInfoChar(&buf, ')');
 
-				/* Print column name and type */
-				appendStringInfo(&buf, "  %s %s",
-								 quote_identifier(attname),
-								 typename);
+			/* Add COLLATE if needed */
+			if (import_collate && collname != NULL && collnamespace != NULL)
+				appendStringInfo(&buf, " COLLATE %s.%s",
+								 quote_identifier(collnamespace),
+								 quote_identifier(collname));
 
-				/*
-				 * Add column_name option so that renaming the foreign table's
-				 * column doesn't break the association to the underlying
-				 * column.
-				 */
-				appendStringInfoString(&buf, " OPTIONS (column_name ");
-				deparseStringLiteral(&buf, attname);
-				appendStringInfoChar(&buf, ')');
-
-				/* Add COLLATE if needed */
-				if (import_collate && collname != NULL && collnamespace != NULL)
-					appendStringInfo(&buf, " COLLATE %s.%s",
-									 quote_identifier(collnamespace),
-									 quote_identifier(collname));
-
-				/* Add DEFAULT if needed */
-				if (import_default && attdefault != NULL &&
-					(!attgenerated || !attgenerated[0]))
-					appendStringInfo(&buf, " DEFAULT %s", attdefault);
-
-				/* Add GENERATED if needed */
-				if (import_generated && attgenerated != NULL &&
-					attgenerated[0] == ATTRIBUTE_GENERATED_STORED)
-				{
-					Assert(attdefault != NULL);
-					appendStringInfo(&buf,
-									 " GENERATED ALWAYS AS (%s) STORED",
-									 attdefault);
-				}
+			/* Add DEFAULT if needed */
+			if (import_default && attdefault != NULL &&
+				(!attgenerated || !attgenerated[0]))
+				appendStringInfo(&buf, " DEFAULT %s", attdefault);
 
-				/* Add NOT NULL if needed */
-				if (import_not_null && attnotnull[0] == 't')
-					appendStringInfoString(&buf, " NOT NULL");
+			/* Add GENERATED if needed */
+			if (import_generated && attgenerated != NULL &&
+				attgenerated[0] == ATTRIBUTE_GENERATED_STORED)
+			{
+				Assert(attdefault != NULL);
+				appendStringInfo(&buf,
+								 " GENERATED ALWAYS AS (%s) STORED",
+								 attdefault);
 			}
-			while (++i < numrows &&
-				   strcmp(PQgetvalue(res, i, 0), tablename) == 0);
 
-			/*
-			 * Add server name and table-level options.  We specify remote
-			 * schema and table name as options (the latter to ensure that
-			 * renaming the foreign table doesn't break the association).
-			 */
-			appendStringInfo(&buf, "\n) SERVER %s\nOPTIONS (",
-							 quote_identifier(server->servername));
+			/* Add NOT NULL if needed */
+			if (import_not_null && attnotnull[0] == 't')
+				appendStringInfoString(&buf, " NOT NULL");
+		}
+		while (++i < numrows &&
+			   strcmp(PQgetvalue(res, i, 0), tablename) == 0);
 
-			appendStringInfoString(&buf, "schema_name ");
-			deparseStringLiteral(&buf, stmt->remote_schema);
-			appendStringInfoString(&buf, ", table_name ");
-			deparseStringLiteral(&buf, tablename);
+		/*
+		 * Add server name and table-level options.  We specify remote schema
+		 * and table name as options (the latter to ensure that renaming the
+		 * foreign table doesn't break the association).
+		 */
+		appendStringInfo(&buf, "\n) SERVER %s\nOPTIONS (",
+						 quote_identifier(server->servername));
 
-			appendStringInfoString(&buf, ");");
+		appendStringInfoString(&buf, "schema_name ");
+		deparseStringLiteral(&buf, stmt->remote_schema);
+		appendStringInfoString(&buf, ", table_name ");
+		deparseStringLiteral(&buf, tablename);
 
-			commands = lappend(commands, pstrdup(buf.data));
-		}
-	}
-	PG_FINALLY();
-	{
-		PQclear(res);
+		appendStringInfoString(&buf, ");");
+
+		commands = lappend(commands, pstrdup(buf.data));
 	}
-	PG_END_TRY();
+	PQclear(res);
 
 	ReleaseConnection(conn);
 
@@ -7417,7 +7312,7 @@ postgresForeignAsyncNotify(AsyncRequest *areq)
 
 	/* On error, report the original query, not the FETCH. */
 	if (!PQconsumeInput(fsstate->conn))
-		pgfdw_report_error(ERROR, NULL, fsstate->conn, false, fsstate->query);
+		pgfdw_report_error(NULL, fsstate->conn, fsstate->query);
 
 	fetch_more_data(node);
 
@@ -7516,7 +7411,7 @@ fetch_more_data_begin(AsyncRequest *areq)
 			 fsstate->fetch_size, fsstate->cursor_number);
 
 	if (!PQsendQuery(fsstate->conn, sql))
-		pgfdw_report_error(ERROR, NULL, fsstate->conn, false, fsstate->query);
+		pgfdw_report_error(NULL, fsstate->conn, fsstate->query);
 
 	/* Remember that the request is in process */
 	fsstate->conn_state->pendingAreq = areq;
diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h
index 81358f3bde7df..e69735298d78f 100644
--- a/contrib/postgres_fdw/postgres_fdw.h
+++ b/contrib/postgres_fdw/postgres_fdw.h
@@ -15,7 +15,7 @@
 
 #include "foreign/foreign.h"
 #include "lib/stringinfo.h"
-#include "libpq-fe.h"
+#include "libpq/libpq-be-fe.h"
 #include "nodes/execnodes.h"
 #include "nodes/pathnodes.h"
 #include "utils/relcache.h"
@@ -166,8 +166,10 @@ extern void do_sql_command(PGconn *conn, const char *sql);
 extern PGresult *pgfdw_get_result(PGconn *conn);
 extern PGresult *pgfdw_exec_query(PGconn *conn, const char *query,
 								  PgFdwConnState *state);
-extern void pgfdw_report_error(int elevel, PGresult *res, PGconn *conn,
-							   bool clear, const char *sql);
+pg_noreturn extern void pgfdw_report_error(PGresult *res, PGconn *conn,
+										   const char *sql);
+extern void pgfdw_report(int elevel, PGresult *res, PGconn *conn,
+						 const char *sql);
 
 /* in option.c */
 extern int	ExtractConnectionOptions(List *defelems,
diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql
index e534b40de3c76..31b6c685b551b 100644
--- a/contrib/postgres_fdw/sql/postgres_fdw.sql
+++ b/contrib/postgres_fdw/sql/postgres_fdw.sql
@@ -352,7 +352,7 @@ EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE c3 IS NULL;        -- Nu
 EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE c3 IS NOT NULL;    -- NullTest
 EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE round(abs(c1), 0) = 1; -- FuncExpr
 EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE c1 = -c1;          -- OpExpr(l)
-EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE (c1 IS NOT NULL) IS DISTINCT FROM (c1 IS NOT NULL); -- DistinctExpr
+EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE (c3 IS NOT NULL) IS DISTINCT FROM (c3 IS NOT NULL); -- DistinctExpr
 EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE c1 = ANY(ARRAY[c2, 1, c1 + 0]); -- ScalarArrayOpExpr
 EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE c1 = (ARRAY[c1,c2,3])[1]; -- SubscriptingRef
 EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE c6 = E'foo''s\\bar';  -- check special chars
@@ -458,6 +458,15 @@ SELECT * FROM ft1 WHERE CASE c3 WHEN c6 THEN true ELSE c3 < 'bar' END;
 EXPLAIN (VERBOSE, COSTS OFF)
 SELECT * FROM ft1 WHERE CASE c3 COLLATE "C" WHEN c6 THEN true ELSE c3 < 'bar' END;
 
+-- Test array type conversion pushdown
+SET plan_cache_mode = force_generic_plan;
+PREPARE s(varchar[]) AS SELECT count(*) FROM ft2 WHERE c6 = ANY ($1);
+EXPLAIN (VERBOSE, COSTS OFF)
+EXECUTE s(ARRAY['1','2']);
+EXECUTE s(ARRAY['1','2']);
+DEALLOCATE s;
+RESET plan_cache_mode;
+
 -- a regconfig constant referring to this text search configuration
 -- is initially unshippable
 CREATE TEXT SEARCH CONFIGURATION public.custom_search
diff --git a/contrib/sepgsql/uavc.c b/contrib/sepgsql/uavc.c
index 65ea8e7946a6e..d9ccbc38bc538 100644
--- a/contrib/sepgsql/uavc.c
+++ b/contrib/sepgsql/uavc.c
@@ -66,8 +66,8 @@ static char *avc_unlabeled;		/* system 'unlabeled' label */
 static uint32
 sepgsql_avc_hash(const char *scontext, const char *tcontext, uint16 tclass)
 {
-	return hash_any((const unsigned char *) scontext, strlen(scontext))
-		^ hash_any((const unsigned char *) tcontext, strlen(tcontext))
+	return hash_bytes((const unsigned char *) scontext, strlen(scontext))
+		^ hash_bytes((const unsigned char *) tcontext, strlen(tcontext))
 		^ tclass;
 }
 
diff --git a/contrib/spi/refint.c b/contrib/spi/refint.c
index d5e25e07ae9e2..89898cad7b0d7 100644
--- a/contrib/spi/refint.c
+++ b/contrib/spi/refint.c
@@ -321,7 +321,7 @@ check_foreign_key(PG_FUNCTION_ARGS)
 	if (nrefs < 1)
 		/* internal error */
 		elog(ERROR, "check_foreign_key: %d (< 1) number of references specified", nrefs);
-	action = tolower((unsigned char) *(args[1]));
+	action = pg_ascii_tolower((unsigned char) *(args[1]));
 	if (action != 'r' && action != 'c' && action != 's')
 		/* internal error */
 		elog(ERROR, "check_foreign_key: invalid action %s", args[1]);
diff --git a/contrib/test_decoding/test_decoding.c b/contrib/test_decoding/test_decoding.c
index bb495563200c3..f671a7d4b3125 100644
--- a/contrib/test_decoding/test_decoding.c
+++ b/contrib/test_decoding/test_decoding.c
@@ -581,7 +581,7 @@ tuple_to_stringinfo(StringInfo s, TupleDesc tupdesc, HeapTuple tuple, bool skip_
 		/* print data */
 		if (isnull)
 			appendStringInfoString(s, "null");
-		else if (typisvarlena && VARATT_IS_EXTERNAL_ONDISK(origval))
+		else if (typisvarlena && VARATT_IS_EXTERNAL_ONDISK(DatumGetPointer(origval)))
 			appendStringInfoString(s, "unchanged-toast-datum");
 		else if (!typisvarlena)
 			print_literal(s, typid,
diff --git a/contrib/xml2/xpath.c b/contrib/xml2/xpath.c
index 23d3f332dbaa7..4ac291c8251f7 100644
--- a/contrib/xml2/xpath.c
+++ b/contrib/xml2/xpath.c
@@ -51,8 +51,8 @@ static text *pgxml_result_to_text(xmlXPathObjectPtr res, xmlChar *toptag,
 
 static xmlChar *pgxml_texttoxmlchar(text *textstring);
 
-static xmlXPathObjectPtr pgxml_xpath(text *document, xmlChar *xpath,
-									 xpath_workspace *workspace);
+static xpath_workspace *pgxml_xpath(text *document, xmlChar *xpath,
+									PgXmlErrorContext *xmlerrcxt);
 
 static void cleanup_workspace(xpath_workspace *workspace);
 
@@ -88,19 +88,41 @@ Datum
 xml_encode_special_chars(PG_FUNCTION_ARGS)
 {
 	text	   *tin = PG_GETARG_TEXT_PP(0);
-	text	   *tout;
-	xmlChar    *ts,
-			   *tt;
+	text	   *volatile tout = NULL;
+	xmlChar    *volatile tt = NULL;
+	PgXmlErrorContext *xmlerrcxt;
+
+	xmlerrcxt = pg_xml_init(PG_XML_STRICTNESS_ALL);
+
+	PG_TRY();
+	{
+		xmlChar    *ts;
 
-	ts = pgxml_texttoxmlchar(tin);
+		ts = pgxml_texttoxmlchar(tin);
+
+		tt = xmlEncodeSpecialChars(NULL, ts);
+		if (tt == NULL || pg_xml_error_occurred(xmlerrcxt))
+			xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY,
+						"could not allocate xmlChar");
+		pfree(ts);
+
+		tout = cstring_to_text((char *) tt);
+	}
+	PG_CATCH();
+	{
+		if (tt != NULL)
+			xmlFree(tt);
 
-	tt = xmlEncodeSpecialChars(NULL, ts);
+		pg_xml_done(xmlerrcxt, true);
 
-	pfree(ts);
+		PG_RE_THROW();
+	}
+	PG_END_TRY();
 
-	tout = cstring_to_text((char *) tt);
+	if (tt != NULL)
+		xmlFree(tt);
 
-	xmlFree(tt);
+	pg_xml_done(xmlerrcxt, false);
 
 	PG_RETURN_TEXT_P(tout);
 }
@@ -122,62 +144,89 @@ pgxmlNodeSetToText(xmlNodeSetPtr nodeset,
 				   xmlChar *septagname,
 				   xmlChar *plainsep)
 {
-	xmlBufferPtr buf;
-	xmlChar    *result;
-	int			i;
+	volatile xmlBufferPtr buf = NULL;
+	xmlChar    *volatile result = NULL;
+	PgXmlErrorContext *xmlerrcxt;
 
-	buf = xmlBufferCreate();
+	/* spin up some error handling */
+	xmlerrcxt = pg_xml_init(PG_XML_STRICTNESS_ALL);
 
-	if ((toptagname != NULL) && (xmlStrlen(toptagname) > 0))
-	{
-		xmlBufferWriteChar(buf, "<");
-		xmlBufferWriteCHAR(buf, toptagname);
-		xmlBufferWriteChar(buf, ">");
-	}
-	if (nodeset != NULL)
+	PG_TRY();
 	{
-		for (i = 0; i < nodeset->nodeNr; i++)
-		{
-			if (plainsep != NULL)
-			{
-				xmlBufferWriteCHAR(buf,
-								   xmlXPathCastNodeToString(nodeset->nodeTab[i]));
+		buf = xmlBufferCreate();
 
-				/* If this isn't the last entry, write the plain sep. */
-				if (i < (nodeset->nodeNr) - 1)
-					xmlBufferWriteChar(buf, (char *) plainsep);
-			}
-			else
+		if (buf == NULL || pg_xml_error_occurred(xmlerrcxt))
+			xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY,
+						"could not allocate xmlBuffer");
+
+		if ((toptagname != NULL) && (xmlStrlen(toptagname) > 0))
+		{
+			xmlBufferWriteChar(buf, "<");
+			xmlBufferWriteCHAR(buf, toptagname);
+			xmlBufferWriteChar(buf, ">");
+		}
+		if (nodeset != NULL)
+		{
+			for (int i = 0; i < nodeset->nodeNr; i++)
 			{
-				if ((septagname != NULL) && (xmlStrlen(septagname) > 0))
+				if (plainsep != NULL)
 				{
-					xmlBufferWriteChar(buf, "<");
-					xmlBufferWriteCHAR(buf, septagname);
-					xmlBufferWriteChar(buf, ">");
-				}
-				xmlNodeDump(buf,
-							nodeset->nodeTab[i]->doc,
-							nodeset->nodeTab[i],
-							1, 0);
+					xmlBufferWriteCHAR(buf,
+									   xmlXPathCastNodeToString(nodeset->nodeTab[i]));
 
-				if ((septagname != NULL) && (xmlStrlen(septagname) > 0))
+					/* If this isn't the last entry, write the plain sep. */
+					if (i < (nodeset->nodeNr) - 1)
+						xmlBufferWriteChar(buf, (char *) plainsep);
+				}
+				else
 				{
-					xmlBufferWriteChar(buf, "</");
-					xmlBufferWriteCHAR(buf, septagname);
-					xmlBufferWriteChar(buf, ">");
+					if ((septagname != NULL) && (xmlStrlen(septagname) > 0))
+					{
+						xmlBufferWriteChar(buf, "<");
+						xmlBufferWriteCHAR(buf, septagname);
+						xmlBufferWriteChar(buf, ">");
+					}
+					xmlNodeDump(buf,
+								nodeset->nodeTab[i]->doc,
+								nodeset->nodeTab[i],
+								1, 0);
+
+					if ((septagname != NULL) && (xmlStrlen(septagname) > 0))
+					{
+						xmlBufferWriteChar(buf, "</");
+						xmlBufferWriteCHAR(buf, septagname);
+						xmlBufferWriteChar(buf, ">");
+					}
 				}
 			}
 		}
-	}
 
-	if ((toptagname != NULL) && (xmlStrlen(toptagname) > 0))
+		if ((toptagname != NULL) && (xmlStrlen(toptagname) > 0))
+		{
+			xmlBufferWriteChar(buf, "</");
+			xmlBufferWriteCHAR(buf, toptagname);
+			xmlBufferWriteChar(buf, ">");
+		}
+
+		result = xmlStrdup(xmlBufferContent(buf));
+		if (result == NULL || pg_xml_error_occurred(xmlerrcxt))
+			xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY,
+						"could not allocate result");
+	}
+	PG_CATCH();
 	{
-		xmlBufferWriteChar(buf, "</");
-		xmlBufferWriteCHAR(buf, toptagname);
-		xmlBufferWriteChar(buf, ">");
+		if (buf)
+			xmlBufferFree(buf);
+
+		pg_xml_done(xmlerrcxt, true);
+
+		PG_RE_THROW();
 	}
-	result = xmlStrdup(buf->content);
+	PG_END_TRY();
+
 	xmlBufferFree(buf);
+	pg_xml_done(xmlerrcxt, false);
+
 	return result;
 }
 
@@ -207,17 +256,30 @@ xpath_nodeset(PG_FUNCTION_ARGS)
 	xmlChar    *toptag = pgxml_texttoxmlchar(PG_GETARG_TEXT_PP(2));
 	xmlChar    *septag = pgxml_texttoxmlchar(PG_GETARG_TEXT_PP(3));
 	xmlChar    *xpath;
-	text	   *xpres;
-	xmlXPathObjectPtr res;
-	xpath_workspace workspace;
+	text	   *volatile xpres = NULL;
+	xpath_workspace *volatile workspace = NULL;
+	PgXmlErrorContext *xmlerrcxt;
 
 	xpath = pgxml_texttoxmlchar(xpathsupp);
+	xmlerrcxt = pgxml_parser_init(PG_XML_STRICTNESS_LEGACY);
 
-	res = pgxml_xpath(document, xpath, &workspace);
+	PG_TRY();
+	{
+		workspace = pgxml_xpath(document, xpath, xmlerrcxt);
+		xpres = pgxml_result_to_text(workspace->res, toptag, septag, NULL);
+	}
+	PG_CATCH();
+	{
+		if (workspace)
+			cleanup_workspace(workspace);
 
-	xpres = pgxml_result_to_text(res, toptag, septag, NULL);
+		pg_xml_done(xmlerrcxt, true);
+		PG_RE_THROW();
+	}
+	PG_END_TRY();
 
-	cleanup_workspace(&workspace);
+	cleanup_workspace(workspace);
+	pg_xml_done(xmlerrcxt, false);
 
 	pfree(xpath);
 
@@ -239,17 +301,30 @@ xpath_list(PG_FUNCTION_ARGS)
 	text	   *xpathsupp = PG_GETARG_TEXT_PP(1);	/* XPath expression */
 	xmlChar    *plainsep = pgxml_texttoxmlchar(PG_GETARG_TEXT_PP(2));
 	xmlChar    *xpath;
-	text	   *xpres;
-	xmlXPathObjectPtr res;
-	xpath_workspace workspace;
+	text	   *volatile xpres = NULL;
+	xpath_workspace *volatile workspace = NULL;
+	PgXmlErrorContext *xmlerrcxt;
 
 	xpath = pgxml_texttoxmlchar(xpathsupp);
+	xmlerrcxt = pgxml_parser_init(PG_XML_STRICTNESS_LEGACY);
 
-	res = pgxml_xpath(document, xpath, &workspace);
+	PG_TRY();
+	{
+		workspace = pgxml_xpath(document, xpath, xmlerrcxt);
+		xpres = pgxml_result_to_text(workspace->res, NULL, NULL, plainsep);
+	}
+	PG_CATCH();
+	{
+		if (workspace)
+			cleanup_workspace(workspace);
 
-	xpres = pgxml_result_to_text(res, NULL, NULL, plainsep);
+		pg_xml_done(xmlerrcxt, true);
+		PG_RE_THROW();
+	}
+	PG_END_TRY();
 
-	cleanup_workspace(&workspace);
+	cleanup_workspace(workspace);
+	pg_xml_done(xmlerrcxt, false);
 
 	pfree(xpath);
 
@@ -268,9 +343,9 @@ xpath_string(PG_FUNCTION_ARGS)
 	text	   *xpathsupp = PG_GETARG_TEXT_PP(1);	/* XPath expression */
 	xmlChar    *xpath;
 	int32		pathsize;
-	text	   *xpres;
-	xmlXPathObjectPtr res;
-	xpath_workspace workspace;
+	text	   *volatile xpres = NULL;
+	xpath_workspace *volatile workspace = NULL;
+	PgXmlErrorContext *xmlerrcxt;
 
 	pathsize = VARSIZE_ANY_EXHDR(xpathsupp);
 
@@ -286,11 +361,25 @@ xpath_string(PG_FUNCTION_ARGS)
 	xpath[pathsize + 7] = ')';
 	xpath[pathsize + 8] = '\0';
 
-	res = pgxml_xpath(document, xpath, &workspace);
+	xmlerrcxt = pgxml_parser_init(PG_XML_STRICTNESS_LEGACY);
+
+	PG_TRY();
+	{
+		workspace = pgxml_xpath(document, xpath, xmlerrcxt);
+		xpres = pgxml_result_to_text(workspace->res, NULL, NULL, NULL);
+	}
+	PG_CATCH();
+	{
+		if (workspace)
+			cleanup_workspace(workspace);
 
-	xpres = pgxml_result_to_text(res, NULL, NULL, NULL);
+		pg_xml_done(xmlerrcxt, true);
+		PG_RE_THROW();
+	}
+	PG_END_TRY();
 
-	cleanup_workspace(&workspace);
+	cleanup_workspace(workspace);
+	pg_xml_done(xmlerrcxt, false);
 
 	pfree(xpath);
 
@@ -308,24 +397,38 @@ xpath_number(PG_FUNCTION_ARGS)
 	text	   *document = PG_GETARG_TEXT_PP(0);
 	text	   *xpathsupp = PG_GETARG_TEXT_PP(1);	/* XPath expression */
 	xmlChar    *xpath;
-	float4		fRes;
-	xmlXPathObjectPtr res;
-	xpath_workspace workspace;
+	volatile float4 fRes = 0.0;
+	volatile bool isNull = false;
+	xpath_workspace *volatile workspace = NULL;
+	PgXmlErrorContext *xmlerrcxt;
 
 	xpath = pgxml_texttoxmlchar(xpathsupp);
+	xmlerrcxt = pgxml_parser_init(PG_XML_STRICTNESS_LEGACY);
 
-	res = pgxml_xpath(document, xpath, &workspace);
-
-	pfree(xpath);
+	PG_TRY();
+	{
+		workspace = pgxml_xpath(document, xpath, xmlerrcxt);
+		pfree(xpath);
 
-	if (res == NULL)
-		PG_RETURN_NULL();
+		if (workspace->res == NULL)
+			isNull = true;
+		else
+			fRes = xmlXPathCastToNumber(workspace->res);
+	}
+	PG_CATCH();
+	{
+		if (workspace)
+			cleanup_workspace(workspace);
 
-	fRes = xmlXPathCastToNumber(res);
+		pg_xml_done(xmlerrcxt, true);
+		PG_RE_THROW();
+	}
+	PG_END_TRY();
 
-	cleanup_workspace(&workspace);
+	cleanup_workspace(workspace);
+	pg_xml_done(xmlerrcxt, false);
 
-	if (xmlXPathIsNaN(fRes))
+	if (isNull || xmlXPathIsNaN(fRes))
 		PG_RETURN_NULL();
 
 	PG_RETURN_FLOAT4(fRes);
@@ -340,22 +443,35 @@ xpath_bool(PG_FUNCTION_ARGS)
 	text	   *document = PG_GETARG_TEXT_PP(0);
 	text	   *xpathsupp = PG_GETARG_TEXT_PP(1);	/* XPath expression */
 	xmlChar    *xpath;
-	int			bRes;
-	xmlXPathObjectPtr res;
-	xpath_workspace workspace;
+	volatile int bRes = 0;
+	xpath_workspace *volatile workspace = NULL;
+	PgXmlErrorContext *xmlerrcxt;
 
 	xpath = pgxml_texttoxmlchar(xpathsupp);
+	xmlerrcxt = pgxml_parser_init(PG_XML_STRICTNESS_LEGACY);
 
-	res = pgxml_xpath(document, xpath, &workspace);
-
-	pfree(xpath);
+	PG_TRY();
+	{
+		workspace = pgxml_xpath(document, xpath, xmlerrcxt);
+		pfree(xpath);
 
-	if (res == NULL)
-		PG_RETURN_BOOL(false);
+		if (workspace->res == NULL)
+			bRes = 0;
+		else
+			bRes = xmlXPathCastToBoolean(workspace->res);
+	}
+	PG_CATCH();
+	{
+		if (workspace)
+			cleanup_workspace(workspace);
 
-	bRes = xmlXPathCastToBoolean(res);
+		pg_xml_done(xmlerrcxt, true);
+		PG_RE_THROW();
+	}
+	PG_END_TRY();
 
-	cleanup_workspace(&workspace);
+	cleanup_workspace(workspace);
+	pg_xml_done(xmlerrcxt, false);
 
 	PG_RETURN_BOOL(bRes);
 }
@@ -364,57 +480,39 @@ xpath_bool(PG_FUNCTION_ARGS)
 
 /* Core function to evaluate XPath query */
 
-static xmlXPathObjectPtr
-pgxml_xpath(text *document, xmlChar *xpath, xpath_workspace *workspace)
+static xpath_workspace *
+pgxml_xpath(text *document, xmlChar *xpath, PgXmlErrorContext *xmlerrcxt)
 {
 	int32		docsize = VARSIZE_ANY_EXHDR(document);
-	PgXmlErrorContext *xmlerrcxt;
 	xmlXPathCompExprPtr comppath;
+	xpath_workspace *workspace = (xpath_workspace *)
+		palloc0(sizeof(xpath_workspace));
 
 	workspace->doctree = NULL;
 	workspace->ctxt = NULL;
 	workspace->res = NULL;
 
-	xmlerrcxt = pgxml_parser_init(PG_XML_STRICTNESS_LEGACY);
-
-	PG_TRY();
+	workspace->doctree = xmlReadMemory((char *) VARDATA_ANY(document),
+									   docsize, NULL, NULL,
+									   XML_PARSE_NOENT);
+	if (workspace->doctree != NULL)
 	{
-		workspace->doctree = xmlReadMemory((char *) VARDATA_ANY(document),
-										   docsize, NULL, NULL,
-										   XML_PARSE_NOENT);
-		if (workspace->doctree != NULL)
-		{
-			workspace->ctxt = xmlXPathNewContext(workspace->doctree);
-			workspace->ctxt->node = xmlDocGetRootElement(workspace->doctree);
-
-			/* compile the path */
-			comppath = xmlXPathCtxtCompile(workspace->ctxt, xpath);
-			if (comppath == NULL)
-				xml_ereport(xmlerrcxt, ERROR, ERRCODE_INVALID_ARGUMENT_FOR_XQUERY,
-							"XPath Syntax Error");
+		workspace->ctxt = xmlXPathNewContext(workspace->doctree);
+		workspace->ctxt->node = xmlDocGetRootElement(workspace->doctree);
 
-			/* Now evaluate the path expression. */
-			workspace->res = xmlXPathCompiledEval(comppath, workspace->ctxt);
+		/* compile the path */
+		comppath = xmlXPathCtxtCompile(workspace->ctxt, xpath);
+		if (comppath == NULL || pg_xml_error_occurred(xmlerrcxt))
+			xml_ereport(xmlerrcxt, ERROR, ERRCODE_INVALID_ARGUMENT_FOR_XQUERY,
+						"XPath Syntax Error");
 
-			xmlXPathFreeCompExpr(comppath);
-		}
-	}
-	PG_CATCH();
-	{
-		cleanup_workspace(workspace);
-
-		pg_xml_done(xmlerrcxt, true);
+		/* Now evaluate the path expression. */
+		workspace->res = xmlXPathCompiledEval(comppath, workspace->ctxt);
 
-		PG_RE_THROW();
+		xmlXPathFreeCompExpr(comppath);
 	}
-	PG_END_TRY();
 
-	if (workspace->res == NULL)
-		cleanup_workspace(workspace);
-
-	pg_xml_done(xmlerrcxt, false);
-
-	return workspace->res;
+	return workspace;
 }
 
 /* Clean up after processing the result of pgxml_xpath() */
@@ -438,35 +536,60 @@ pgxml_result_to_text(xmlXPathObjectPtr res,
 					 xmlChar *septag,
 					 xmlChar *plainsep)
 {
-	xmlChar    *xpresstr;
-	text	   *xpres;
+	xmlChar    *volatile xpresstr = NULL;
+	text	   *volatile xpres = NULL;
+	PgXmlErrorContext *xmlerrcxt;
 
 	if (res == NULL)
 		return NULL;
 
-	switch (res->type)
-	{
-		case XPATH_NODESET:
-			xpresstr = pgxmlNodeSetToText(res->nodesetval,
-										  toptag,
-										  septag, plainsep);
-			break;
+	/* spin some error handling */
+	xmlerrcxt = pg_xml_init(PG_XML_STRICTNESS_ALL);
 
-		case XPATH_STRING:
-			xpresstr = xmlStrdup(res->stringval);
-			break;
+	PG_TRY();
+	{
+		switch (res->type)
+		{
+			case XPATH_NODESET:
+				xpresstr = pgxmlNodeSetToText(res->nodesetval,
+											  toptag,
+											  septag, plainsep);
+				break;
+
+			case XPATH_STRING:
+				xpresstr = xmlStrdup(res->stringval);
+				if (xpresstr == NULL || pg_xml_error_occurred(xmlerrcxt))
+					xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY,
+								"could not allocate result");
+				break;
+
+			default:
+				elog(NOTICE, "unsupported XQuery result: %d", res->type);
+				xpresstr = xmlStrdup((const xmlChar *) "<unsupported/>");
+				if (xpresstr == NULL || pg_xml_error_occurred(xmlerrcxt))
+					xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY,
+								"could not allocate result");
+		}
 
-		default:
-			elog(NOTICE, "unsupported XQuery result: %d", res->type);
-			xpresstr = xmlStrdup((const xmlChar *) "<unsupported/>");
+		/* Now convert this result back to text */
+		xpres = cstring_to_text((char *) xpresstr);
 	}
+	PG_CATCH();
+	{
+		if (xpresstr != NULL)
+			xmlFree(xpresstr);
 
-	/* Now convert this result back to text */
-	xpres = cstring_to_text((char *) xpresstr);
+		pg_xml_done(xmlerrcxt, true);
+
+		PG_RE_THROW();
+	}
+	PG_END_TRY();
 
 	/* Free various storage */
 	xmlFree(xpresstr);
 
+	pg_xml_done(xmlerrcxt, false);
+
 	return xpres;
 }
 
@@ -648,11 +771,16 @@ xpath_table(PG_FUNCTION_ARGS)
 					for (j = 0; j < numpaths; j++)
 					{
 						ctxt = xmlXPathNewContext(doctree);
+						if (ctxt == NULL || pg_xml_error_occurred(xmlerrcxt))
+							xml_ereport(xmlerrcxt,
+										ERROR, ERRCODE_OUT_OF_MEMORY,
+										"could not allocate XPath context");
+
 						ctxt->node = xmlDocGetRootElement(doctree);
 
 						/* compile the path */
 						comppath = xmlXPathCtxtCompile(ctxt, xpaths[j]);
-						if (comppath == NULL)
+						if (comppath == NULL || pg_xml_error_occurred(xmlerrcxt))
 							xml_ereport(xmlerrcxt, ERROR,
 										ERRCODE_INVALID_ARGUMENT_FOR_XQUERY,
 										"XPath Syntax Error");
@@ -671,6 +799,10 @@ xpath_table(PG_FUNCTION_ARGS)
 										rownr < res->nodesetval->nodeNr)
 									{
 										resstr = xmlXPathCastNodeToString(res->nodesetval->nodeTab[rownr]);
+										if (resstr == NULL || pg_xml_error_occurred(xmlerrcxt))
+											xml_ereport(xmlerrcxt,
+														ERROR, ERRCODE_OUT_OF_MEMORY,
+														"could not allocate result");
 										had_values = true;
 									}
 									else
@@ -680,11 +812,19 @@ xpath_table(PG_FUNCTION_ARGS)
 
 								case XPATH_STRING:
 									resstr = xmlStrdup(res->stringval);
+									if (resstr == NULL || pg_xml_error_occurred(xmlerrcxt))
+										xml_ereport(xmlerrcxt,
+													ERROR, ERRCODE_OUT_OF_MEMORY,
+													"could not allocate result");
 									break;
 
 								default:
 									elog(NOTICE, "unsupported XQuery result: %d", res->type);
 									resstr = xmlStrdup((const xmlChar *) "<unsupported/>");
+									if (resstr == NULL || pg_xml_error_occurred(xmlerrcxt))
+										xml_ereport(xmlerrcxt,
+													ERROR, ERRCODE_OUT_OF_MEMORY,
+													"could not allocate result");
 							}
 
 							/*
diff --git a/contrib/xml2/xslt_proc.c b/contrib/xml2/xslt_proc.c
index b720d89f754ae..53550c7dc2406 100644
--- a/contrib/xml2/xslt_proc.c
+++ b/contrib/xml2/xslt_proc.c
@@ -48,7 +48,7 @@ xslt_process(PG_FUNCTION_ARGS)
 
 	text	   *doct = PG_GETARG_TEXT_PP(0);
 	text	   *ssheet = PG_GETARG_TEXT_PP(1);
-	text	   *result;
+	text	   *volatile result = NULL;
 	text	   *paramstr;
 	const char **params;
 	PgXmlErrorContext *xmlerrcxt;
@@ -58,8 +58,7 @@ xslt_process(PG_FUNCTION_ARGS)
 	volatile xsltSecurityPrefsPtr xslt_sec_prefs = NULL;
 	volatile xsltTransformContextPtr xslt_ctxt = NULL;
 	volatile int resstat = -1;
-	xmlChar    *resstr = NULL;
-	int			reslen = 0;
+	xmlChar    *volatile resstr = NULL;
 
 	if (fcinfo->nargs == 3)
 	{
@@ -80,13 +79,14 @@ xslt_process(PG_FUNCTION_ARGS)
 	{
 		xmlDocPtr	ssdoc;
 		bool		xslt_sec_prefs_error;
+		int			reslen = 0;
 
 		/* Parse document */
 		doctree = xmlReadMemory((char *) VARDATA_ANY(doct),
 								VARSIZE_ANY_EXHDR(doct), NULL, NULL,
 								XML_PARSE_NOENT);
 
-		if (doctree == NULL)
+		if (doctree == NULL || pg_xml_error_occurred(xmlerrcxt))
 			xml_ereport(xmlerrcxt, ERROR, ERRCODE_INVALID_XML_DOCUMENT,
 						"error parsing XML document");
 
@@ -95,14 +95,14 @@ xslt_process(PG_FUNCTION_ARGS)
 							  VARSIZE_ANY_EXHDR(ssheet), NULL, NULL,
 							  XML_PARSE_NOENT);
 
-		if (ssdoc == NULL)
+		if (ssdoc == NULL || pg_xml_error_occurred(xmlerrcxt))
 			xml_ereport(xmlerrcxt, ERROR, ERRCODE_INVALID_XML_DOCUMENT,
 						"error parsing stylesheet as XML document");
 
 		/* After this call we need not free ssdoc separately */
 		stylesheet = xsltParseStylesheetDoc(ssdoc);
 
-		if (stylesheet == NULL)
+		if (stylesheet == NULL || pg_xml_error_occurred(xmlerrcxt))
 			xml_ereport(xmlerrcxt, ERROR, ERRCODE_INVALID_ARGUMENT_FOR_XQUERY,
 						"failed to parse stylesheet");
 
@@ -137,11 +137,15 @@ xslt_process(PG_FUNCTION_ARGS)
 		restree = xsltApplyStylesheetUser(stylesheet, doctree, params,
 										  NULL, NULL, xslt_ctxt);
 
-		if (restree == NULL)
+		if (restree == NULL || pg_xml_error_occurred(xmlerrcxt))
 			xml_ereport(xmlerrcxt, ERROR, ERRCODE_INVALID_ARGUMENT_FOR_XQUERY,
 						"failed to apply stylesheet");
 
-		resstat = xsltSaveResultToString(&resstr, &reslen, restree, stylesheet);
+		resstat = xsltSaveResultToString((xmlChar **) &resstr, &reslen,
+										 restree, stylesheet);
+
+		if (resstat >= 0)
+			result = cstring_to_text_with_len((char *) resstr, reslen);
 	}
 	PG_CATCH();
 	{
@@ -155,6 +159,8 @@ xslt_process(PG_FUNCTION_ARGS)
 			xsltFreeStylesheet(stylesheet);
 		if (doctree != NULL)
 			xmlFreeDoc(doctree);
+		if (resstr != NULL)
+			xmlFree(resstr);
 		xsltCleanupGlobals();
 
 		pg_xml_done(xmlerrcxt, true);
@@ -170,17 +176,15 @@ xslt_process(PG_FUNCTION_ARGS)
 	xmlFreeDoc(doctree);
 	xsltCleanupGlobals();
 
+	if (resstr)
+		xmlFree(resstr);
+
 	pg_xml_done(xmlerrcxt, false);
 
 	/* XXX this is pretty dubious, really ought to throw error instead */
 	if (resstat < 0)
 		PG_RETURN_NULL();
 
-	result = cstring_to_text_with_len((char *) resstr, reslen);
-
-	if (resstr)
-		xmlFree(resstr);
-
 	PG_RETURN_TEXT_P(result);
 #else							/* !USE_LIBXSLT */
 
diff --git a/doc/src/sgml/amcheck.sgml b/doc/src/sgml/amcheck.sgml
index 211a0ae1945bb..0aff0a6c8c6fc 100644
--- a/doc/src/sgml/amcheck.sgml
+++ b/doc/src/sgml/amcheck.sgml
@@ -278,8 +278,8 @@ SET client_min_messages = DEBUG1;
          TOAST table.
         </para>
         <para>
-         This option is known to be slow.  Also, if the toast table or its
-         index is corrupt, checking it against toast values could conceivably
+         This option is known to be slow.  Also, if the TOAST table or its
+         index is corrupt, checking it against TOAST values could conceivably
          crash the server, although in many cases this would just produce an
          error.
         </para>
diff --git a/doc/src/sgml/backup.sgml b/doc/src/sgml/backup.sgml
index 25b8904baf7cd..5f7489afbd165 100644
--- a/doc/src/sgml/backup.sgml
+++ b/doc/src/sgml/backup.sgml
@@ -991,7 +991,7 @@ SELECT pg_backup_start(label => 'label', fast => false);
      usually preferable as it minimizes the impact on the running system.  If you
      want to start the backup as soon as possible, pass <literal>true</literal> as
      the second parameter to <function>pg_backup_start</function> and it will
-     request an immediate checkpoint, which will finish as fast as possible using
+     request a fast checkpoint, which will finish as fast as possible using
      as much I/O as possible.
     </para>
 
diff --git a/doc/src/sgml/bki.sgml b/doc/src/sgml/bki.sgml
index 3cd5bee7ffaf4..53a982bf60d29 100644
--- a/doc/src/sgml/bki.sgml
+++ b/doc/src/sgml/bki.sgml
@@ -1042,7 +1042,7 @@ $ perl  rewrite_dat_with_prokind.pl  pg_proc.dat
     </listitem>
     <listitem>
      <para>
-      Define indexes and toast tables.
+      Define indexes and TOAST tables.
      </para>
     </listitem>
     <listitem>
diff --git a/doc/src/sgml/catalogs.sgml b/doc/src/sgml/catalogs.sgml
index fa86c569dc497..da8a78825809f 100644
--- a/doc/src/sgml/catalogs.sgml
+++ b/doc/src/sgml/catalogs.sgml
@@ -1951,7 +1951,7 @@ SCRAM-SHA-256$<replaceable>&lt;iteration count&gt;</replaceable>:<replaceable>&l
       </para>
       <para>
        The OID of the data type that corresponds to this table's row type,
-       if any; zero for indexes, sequences, and toast tables, which have
+       if any; zero for indexes, sequences, and TOAST tables, which have
        no <structname>pg_type</structname> entry
       </para></entry>
      </row>
@@ -3158,7 +3158,7 @@ SCRAM-SHA-256$<replaceable>&lt;iteration count&gt;</replaceable>:<replaceable>&l
        <structfield>datcollate</structfield> <type>text</type>
       </para>
       <para>
-       LC_COLLATE for this database
+       LC_COLLATE for this database (ignored unless <structfield>datlocprovider</structfield> is <literal>c</literal>)
       </para></entry>
      </row>
 
@@ -7971,7 +7971,7 @@ SCRAM-SHA-256$<replaceable>&lt;iteration count&gt;</replaceable>:<replaceable>&l
       </para>
       <para>
        Finish LSN of the transaction whose changes are to be skipped, if a valid
-       LSN; otherwise <literal>0/0</literal>.
+       LSN; otherwise <literal>0/0000000</literal>.
       </para></entry>
      </row>
 
@@ -8082,6 +8082,18 @@ SCRAM-SHA-256$<replaceable>&lt;iteration count&gt;</replaceable>:<replaceable>&l
       </para></entry>
      </row>
 
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>subretaindeadtuples</structfield> <type>bool</type>
+      </para>
+      <para>
+       If true, the detection of <xref linkend="conflict-update-deleted"/> is
+       enabled and the information (e.g., dead tuples, commit timestamps, and
+       origins) on the subscriber that is useful for conflict detection is
+       retained.
+      </para></entry>
+     </row>
+
      <row>
       <entry role="catalog_table_entry"><para role="column_definition">
        <structfield>subconninfo</structfield> <type>text</type>
diff --git a/doc/src/sgml/charset.sgml b/doc/src/sgml/charset.sgml
index 5a0e97f6f3158..59b27c3c370e2 100644
--- a/doc/src/sgml/charset.sgml
+++ b/doc/src/sgml/charset.sgml
@@ -100,7 +100,7 @@ initdb --locale=sv_SE
       <tbody>
        <row>
         <entry><envar>LC_COLLATE</envar></entry>
-        <entry>String sort order</entry>
+        <entry>String sort order (ignored unless the provider is <literal>libc</literal>)</entry>
        </row>
        <row>
         <entry><envar>LC_CTYPE</envar></entry>
diff --git a/doc/src/sgml/client-auth.sgml b/doc/src/sgml/client-auth.sgml
index 832b616a7bbff..51b95ed04f399 100644
--- a/doc/src/sgml/client-auth.sgml
+++ b/doc/src/sgml/client-auth.sgml
@@ -1003,8 +1003,9 @@ local   db1,db2,@demodbs  all                                   md5
    the remainder of the field is treated as a regular expression.
    (See <xref linkend="posix-syntax-details"/> for details of
    <productname>PostgreSQL</productname>'s regular expression syntax.)  The regular
-   expression can include a single capture, or parenthesized subexpression,
-   which can then be referenced in the <replaceable>database-username</replaceable>
+   expression can include a single capture, or parenthesized subexpression.
+   The portion of the system user name that matched the capture can then
+   be referenced in the <replaceable>database-username</replaceable>
    field as <literal>\1</literal> (backslash-one).  This allows the mapping of
    multiple user names in a single line, which is particularly useful for
    simple syntax substitutions.  For example, these entries
@@ -1022,12 +1023,11 @@ mymap   /^(.*)@otherdomain\.com$   guest
   <para>
    If the <replaceable>database-username</replaceable> field starts with
    a slash (<literal>/</literal>), the remainder of the field is treated
-   as a regular expression (see <xref linkend="posix-syntax-details"/>
-   for details of <productname>PostgreSQL</productname>'s regular
-   expression syntax). It is not possible to use <literal>\1</literal>
-   to use a capture from regular expression on
-   <replaceable>system-username</replaceable> for a regular expression
-   on <replaceable>database-username</replaceable>.
+   as a regular expression.
+   When the <replaceable>database-username</replaceable> field is a regular
+   expression, it is not possible to use <literal>\1</literal> within it to
+   refer to a capture from the <replaceable>system-username</replaceable>
+   field.
   </para>
 
   <tip>
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 59a0874528a3a..20ccb2d6b5447 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -4618,10 +4618,12 @@ restore_command = 'copy "C:\\server\\archivedir\\%f" "%p"'  # Windows
       </term>
       <listitem>
        <para>
-        Invalidate replication slots that have remained idle longer than this
-        duration. If this value is specified without units, it is taken as
-        minutes. A value of zero (the default) disables the idle timeout
-        invalidation mechanism. This parameter can only be set in the
+        Invalidate replication slots that have remained inactive (not used by
+        a <link linkend="protocol-replication">replication connection</link>)
+        for longer than this duration.
+        If this value is specified without units, it is taken as seconds.
+        A value of zero (the default) disables the idle timeout
+        invalidation mechanism.  This parameter can only be set in the
         <filename>postgresql.conf</filename> file or on the server command
         line.
        </para>
@@ -4963,6 +4965,8 @@ ANY <replaceable class="parameter">num_sync</replaceable> ( <replaceable class="
           new setting.
           This setting has no effect if <varname>primary_conninfo</varname> is not
           set or the server is not in standby mode.
+          The name cannot be <literal>pg_conflict_detection</literal> as it is
+          reserved for the conflict detection slot.
          </para>
         </listitem>
        </varlistentry>
diff --git a/doc/src/sgml/datatype.sgml b/doc/src/sgml/datatype.sgml
index 09309ba0390b7..0994e08931155 100644
--- a/doc/src/sgml/datatype.sgml
+++ b/doc/src/sgml/datatype.sgml
@@ -4737,6 +4737,10 @@ INSERT INTO mytable VALUES(-1);  -- fails
     <primary>regconfig</primary>
    </indexterm>
 
+   <indexterm zone="datatype-oid">
+    <primary>regdatabase</primary>
+   </indexterm>
+
    <indexterm zone="datatype-oid">
     <primary>regdictionary</primary>
    </indexterm>
@@ -4878,6 +4882,13 @@ SELECT * FROM pg_attribute
         <entry><literal>english</literal></entry>
        </row>
 
+       <row>
+        <entry><type>regdatabase</type></entry>
+        <entry><structname>pg_database</structname></entry>
+        <entry>database name</entry>
+        <entry><literal>template1</literal></entry>
+       </row>
+
        <row>
         <entry><type>regdictionary</type></entry>
         <entry><structname>pg_ts_dict</structname></entry>
@@ -5049,8 +5060,8 @@ WHERE ...
     be dropped without first removing the default expression.  The
     alternative of <literal>nextval('my_seq'::text)</literal> does not
     create a dependency.
-    (<type>regrole</type> is an exception to this property. Constants of this
-    type are not allowed in stored expressions.)
+    (<type>regdatabase</type> and <type>regrole</type> are exceptions to this
+    property.  Constants of these types are not allowed in stored expressions.)
    </para>
 
    <para>
@@ -5110,7 +5121,7 @@ WHERE ...
     <literal>+(pg_lsn,numeric)</literal> and
     <literal>-(pg_lsn,numeric)</literal> operators, respectively. Note that
     the calculated LSN should be in the range of <type>pg_lsn</type> type,
-    i.e., between <literal>0/0</literal> and
+    i.e., between <literal>0/00000000</literal> and
     <literal>FFFFFFFF/FFFFFFFF</literal>.
    </para>
   </sect1>
diff --git a/doc/src/sgml/filelist.sgml b/doc/src/sgml/filelist.sgml
index bcde3cfd0374a..ac66fcbdb5727 100644
--- a/doc/src/sgml/filelist.sgml
+++ b/doc/src/sgml/filelist.sgml
@@ -17,7 +17,10 @@
 <!ENTITY datatype   SYSTEM "datatype.sgml">
 <!ENTITY ddl        SYSTEM "ddl.sgml">
 <!ENTITY dml        SYSTEM "dml.sgml">
-<!ENTITY func       SYSTEM "func.sgml">
+
+<!ENTITY % allfiles_func   SYSTEM "func/allfiles.sgml">
+%allfiles_func;
+
 <!ENTITY indices    SYSTEM "indices.sgml">
 <!ENTITY json       SYSTEM "json.sgml">
 <!ENTITY mvcc       SYSTEM "mvcc.sgml">
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
deleted file mode 100644
index 224d4fe5a9f95..0000000000000
--- a/doc/src/sgml/func.sgml
+++ /dev/null
@@ -1,32021 +0,0 @@
-<!-- doc/src/sgml/func.sgml -->
-
- <chapter id="functions">
-  <title>Functions and Operators</title>
-
-  <indexterm zone="functions">
-   <primary>function</primary>
-  </indexterm>
-
-  <indexterm zone="functions">
-   <primary>operator</primary>
-  </indexterm>
-
-  <para>
-   <productname>PostgreSQL</productname> provides a large number of
-   functions and operators for the built-in data types.  This chapter
-   describes most of them, although additional special-purpose functions
-   appear in relevant sections of the manual.  Users can also
-   define their own functions and operators, as described in
-   <xref linkend="server-programming"/>.  The
-   <application>psql</application> commands <command>\df</command> and
-   <command>\do</command> can be used to list all
-   available functions and operators, respectively.
-  </para>
-
-  <para>
-   The notation used throughout this chapter to describe the argument and
-   result data types of a function or operator is like this:
-<synopsis>
-<function>repeat</function> ( <type>text</type>, <type>integer</type> ) <returnvalue>text</returnvalue>
-</synopsis>
-   which says that the function <function>repeat</function> takes one text and
-   one integer argument and returns a result of type text.  The right arrow
-   is also used to indicate the result of an example, thus:
-<programlisting>
-repeat('Pg', 4) <returnvalue>PgPgPgPg</returnvalue>
-</programlisting>
-  </para>
-
-  <para>
-   If you are concerned about portability then note that most of
-   the functions and operators described in this chapter, with the
-   exception of the most trivial arithmetic and comparison operators
-   and some explicitly marked functions, are not specified by the
-   <acronym>SQL</acronym> standard. Some of this extended functionality
-   is present in other <acronym>SQL</acronym> database management
-   systems, and in many cases this functionality is compatible and
-   consistent between the various implementations.
-  </para>
-
-
-  <sect1 id="functions-logical">
-   <title>Logical Operators</title>
-
-   <indexterm zone="functions-logical">
-    <primary>operator</primary>
-    <secondary>logical</secondary>
-   </indexterm>
-
-   <indexterm>
-    <primary>Boolean</primary>
-    <secondary>operators</secondary>
-    <see>operators, logical</see>
-   </indexterm>
-
-   <para>
-    The usual logical operators are available:
-
-    <indexterm>
-     <primary>AND (operator)</primary>
-    </indexterm>
-
-    <indexterm>
-     <primary>OR (operator)</primary>
-    </indexterm>
-
-    <indexterm>
-     <primary>NOT (operator)</primary>
-    </indexterm>
-
-    <indexterm>
-     <primary>conjunction</primary>
-    </indexterm>
-
-    <indexterm>
-     <primary>disjunction</primary>
-    </indexterm>
-
-    <indexterm>
-     <primary>negation</primary>
-    </indexterm>
-
-<synopsis>
-<type>boolean</type> <literal>AND</literal> <type>boolean</type> <returnvalue>boolean</returnvalue>
-<type>boolean</type> <literal>OR</literal> <type>boolean</type> <returnvalue>boolean</returnvalue>
-<literal>NOT</literal> <type>boolean</type> <returnvalue>boolean</returnvalue>
-</synopsis>
-
-    <acronym>SQL</acronym> uses a three-valued logic system with true,
-    false, and <literal>null</literal>, which represents <quote>unknown</quote>.
-    Observe the following truth tables:
-
-    <informaltable>
-     <tgroup cols="4">
-      <thead>
-       <row>
-        <entry><replaceable>a</replaceable></entry>
-        <entry><replaceable>b</replaceable></entry>
-        <entry><replaceable>a</replaceable> AND <replaceable>b</replaceable></entry>
-        <entry><replaceable>a</replaceable> OR <replaceable>b</replaceable></entry>
-       </row>
-      </thead>
-
-      <tbody>
-       <row>
-        <entry>TRUE</entry>
-        <entry>TRUE</entry>
-        <entry>TRUE</entry>
-        <entry>TRUE</entry>
-       </row>
-
-       <row>
-        <entry>TRUE</entry>
-        <entry>FALSE</entry>
-        <entry>FALSE</entry>
-        <entry>TRUE</entry>
-       </row>
-
-       <row>
-        <entry>TRUE</entry>
-        <entry>NULL</entry>
-        <entry>NULL</entry>
-        <entry>TRUE</entry>
-       </row>
-
-       <row>
-        <entry>FALSE</entry>
-        <entry>FALSE</entry>
-        <entry>FALSE</entry>
-        <entry>FALSE</entry>
-       </row>
-
-       <row>
-        <entry>FALSE</entry>
-        <entry>NULL</entry>
-        <entry>FALSE</entry>
-        <entry>NULL</entry>
-       </row>
-
-       <row>
-        <entry>NULL</entry>
-        <entry>NULL</entry>
-        <entry>NULL</entry>
-        <entry>NULL</entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </informaltable>
-
-    <informaltable>
-     <tgroup cols="2">
-      <thead>
-       <row>
-        <entry><replaceable>a</replaceable></entry>
-        <entry>NOT <replaceable>a</replaceable></entry>
-       </row>
-      </thead>
-
-      <tbody>
-       <row>
-        <entry>TRUE</entry>
-        <entry>FALSE</entry>
-       </row>
-
-       <row>
-        <entry>FALSE</entry>
-        <entry>TRUE</entry>
-       </row>
-
-       <row>
-        <entry>NULL</entry>
-        <entry>NULL</entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </informaltable>
-   </para>
-
-   <para>
-    The operators <literal>AND</literal> and <literal>OR</literal> are
-    commutative, that is, you can switch the left and right operands
-    without affecting the result.  (However, it is not guaranteed that
-    the left operand is evaluated before the right operand.  See <xref
-    linkend="syntax-express-eval"/> for more information about the
-    order of evaluation of subexpressions.)
-   </para>
-  </sect1>
-
-  <sect1 id="functions-comparison">
-   <title>Comparison Functions and Operators</title>
-
-   <indexterm zone="functions-comparison">
-    <primary>comparison</primary>
-    <secondary>operators</secondary>
-   </indexterm>
-
-   <para>
-    The usual comparison operators are available, as shown in <xref
-    linkend="functions-comparison-op-table"/>.
-   </para>
-
-   <table id="functions-comparison-op-table">
-    <title>Comparison Operators</title>
-    <tgroup cols="2">
-     <thead>
-      <row>
-       <entry>Operator</entry>
-       <entry>Description</entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry>
-        <replaceable>datatype</replaceable> <literal>&lt;</literal> <replaceable>datatype</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </entry>
-       <entry>Less than</entry>
-      </row>
-
-      <row>
-       <entry>
-        <replaceable>datatype</replaceable> <literal>&gt;</literal> <replaceable>datatype</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </entry>
-       <entry>Greater than</entry>
-      </row>
-
-      <row>
-       <entry>
-        <replaceable>datatype</replaceable> <literal>&lt;=</literal> <replaceable>datatype</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </entry>
-       <entry>Less than or equal to</entry>
-      </row>
-
-      <row>
-       <entry>
-        <replaceable>datatype</replaceable> <literal>&gt;=</literal> <replaceable>datatype</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </entry>
-       <entry>Greater than or equal to</entry>
-      </row>
-
-      <row>
-       <entry>
-        <replaceable>datatype</replaceable> <literal>=</literal> <replaceable>datatype</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </entry>
-       <entry>Equal</entry>
-      </row>
-
-      <row>
-       <entry>
-        <replaceable>datatype</replaceable> <literal>&lt;&gt;</literal> <replaceable>datatype</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </entry>
-       <entry>Not equal</entry>
-      </row>
-
-      <row>
-       <entry>
-        <replaceable>datatype</replaceable> <literal>!=</literal> <replaceable>datatype</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </entry>
-       <entry>Not equal</entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <note>
-    <para>
-     <literal>&lt;&gt;</literal> is the standard SQL notation for <quote>not
-     equal</quote>.  <literal>!=</literal> is an alias, which is converted
-     to <literal>&lt;&gt;</literal> at a very early stage of parsing.
-     Hence, it is not possible to implement <literal>!=</literal>
-     and <literal>&lt;&gt;</literal> operators that do different things.
-    </para>
-   </note>
-
-   <para>
-    These comparison operators are available for all built-in data types
-    that have a natural ordering, including numeric, string, and date/time
-    types.  In addition, arrays, composite types, and ranges can be compared
-    if their component data types are comparable.
-   </para>
-
-   <para>
-    It is usually possible to compare values of related data
-    types as well; for example <type>integer</type> <literal>&gt;</literal>
-    <type>bigint</type> will work.  Some cases of this sort are implemented
-    directly by <quote>cross-type</quote> comparison operators, but if no
-    such operator is available, the parser will coerce the less-general type
-    to the more-general type and apply the latter's comparison operator.
-   </para>
-
-   <para>
-    As shown above, all comparison operators are binary operators that
-    return values of type <type>boolean</type>.  Thus, expressions like
-    <literal>1 &lt; 2 &lt; 3</literal> are not valid (because there is
-    no <literal>&lt;</literal> operator to compare a Boolean value with
-    <literal>3</literal>).  Use the <literal>BETWEEN</literal> predicates
-    shown below to perform range tests.
-   </para>
-
-   <para>
-    There are also some comparison predicates, as shown in <xref
-    linkend="functions-comparison-pred-table"/>.  These behave much like
-    operators, but have special syntax mandated by the SQL standard.
-   </para>
-
-   <table id="functions-comparison-pred-table">
-    <title>Comparison Predicates</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Predicate
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>datatype</replaceable> <literal>BETWEEN</literal> <replaceable>datatype</replaceable> <literal>AND</literal> <replaceable>datatype</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Between (inclusive of the range endpoints).
-       </para>
-       <para>
-        <literal>2 BETWEEN 1 AND 3</literal>
-        <returnvalue>t</returnvalue>
-       </para>
-       <para>
-        <literal>2 BETWEEN 3 AND 1</literal>
-        <returnvalue>f</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>datatype</replaceable> <literal>NOT BETWEEN</literal> <replaceable>datatype</replaceable> <literal>AND</literal> <replaceable>datatype</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Not between (the negation of <literal>BETWEEN</literal>).
-       </para>
-       <para>
-        <literal>2 NOT BETWEEN 1 AND 3</literal>
-        <returnvalue>f</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>datatype</replaceable> <literal>BETWEEN SYMMETRIC</literal> <replaceable>datatype</replaceable> <literal>AND</literal> <replaceable>datatype</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Between, after sorting the two endpoint values.
-       </para>
-       <para>
-        <literal>2 BETWEEN SYMMETRIC 3 AND 1</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>datatype</replaceable> <literal>NOT BETWEEN SYMMETRIC</literal> <replaceable>datatype</replaceable> <literal>AND</literal> <replaceable>datatype</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Not between, after sorting the two endpoint values.
-       </para>
-       <para>
-        <literal>2 NOT BETWEEN SYMMETRIC 3 AND 1</literal>
-        <returnvalue>f</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>datatype</replaceable> <literal>IS DISTINCT FROM</literal> <replaceable>datatype</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Not equal, treating null as a comparable value.
-       </para>
-       <para>
-        <literal>1 IS DISTINCT FROM NULL</literal>
-        <returnvalue>t</returnvalue> (rather than <literal>NULL</literal>)
-       </para>
-       <para>
-        <literal>NULL IS DISTINCT FROM NULL</literal>
-        <returnvalue>f</returnvalue> (rather than <literal>NULL</literal>)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>datatype</replaceable> <literal>IS NOT DISTINCT FROM</literal> <replaceable>datatype</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Equal, treating null as a comparable value.
-       </para>
-       <para>
-        <literal>1 IS NOT DISTINCT FROM NULL</literal>
-        <returnvalue>f</returnvalue> (rather than <literal>NULL</literal>)
-       </para>
-       <para>
-        <literal>NULL IS NOT DISTINCT FROM NULL</literal>
-        <returnvalue>t</returnvalue> (rather than <literal>NULL</literal>)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>datatype</replaceable> <literal>IS NULL</literal>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Test whether value is null.
-       </para>
-       <para>
-        <literal>1.5 IS NULL</literal>
-        <returnvalue>f</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>datatype</replaceable> <literal>IS NOT NULL</literal>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Test whether value is not null.
-       </para>
-       <para>
-        <literal>'null' IS NOT NULL</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>datatype</replaceable> <literal>ISNULL</literal>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Test whether value is null (nonstandard syntax).
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>datatype</replaceable> <literal>NOTNULL</literal>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Test whether value is not null (nonstandard syntax).
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>boolean</type> <literal>IS TRUE</literal>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Test whether boolean expression yields true.
-       </para>
-       <para>
-        <literal>true IS TRUE</literal>
-        <returnvalue>t</returnvalue>
-       </para>
-       <para>
-        <literal>NULL::boolean IS TRUE</literal>
-        <returnvalue>f</returnvalue> (rather than <literal>NULL</literal>)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>boolean</type> <literal>IS NOT TRUE</literal>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Test whether boolean expression yields false or unknown.
-       </para>
-       <para>
-        <literal>true IS NOT TRUE</literal>
-        <returnvalue>f</returnvalue>
-       </para>
-       <para>
-        <literal>NULL::boolean IS NOT TRUE</literal>
-        <returnvalue>t</returnvalue> (rather than <literal>NULL</literal>)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>boolean</type> <literal>IS FALSE</literal>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Test whether boolean expression yields false.
-       </para>
-       <para>
-        <literal>true IS FALSE</literal>
-        <returnvalue>f</returnvalue>
-       </para>
-       <para>
-        <literal>NULL::boolean IS FALSE</literal>
-        <returnvalue>f</returnvalue> (rather than <literal>NULL</literal>)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>boolean</type> <literal>IS NOT FALSE</literal>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Test whether boolean expression yields true or unknown.
-       </para>
-       <para>
-        <literal>true IS NOT FALSE</literal>
-        <returnvalue>t</returnvalue>
-       </para>
-       <para>
-        <literal>NULL::boolean IS NOT FALSE</literal>
-        <returnvalue>t</returnvalue> (rather than <literal>NULL</literal>)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>boolean</type> <literal>IS UNKNOWN</literal>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Test whether boolean expression yields unknown.
-       </para>
-       <para>
-        <literal>true IS UNKNOWN</literal>
-        <returnvalue>f</returnvalue>
-       </para>
-       <para>
-        <literal>NULL::boolean IS UNKNOWN</literal>
-        <returnvalue>t</returnvalue> (rather than <literal>NULL</literal>)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>boolean</type> <literal>IS NOT UNKNOWN</literal>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Test whether boolean expression yields true or false.
-       </para>
-       <para>
-        <literal>true IS NOT UNKNOWN</literal>
-        <returnvalue>t</returnvalue>
-       </para>
-       <para>
-        <literal>NULL::boolean IS NOT UNKNOWN</literal>
-        <returnvalue>f</returnvalue> (rather than <literal>NULL</literal>)
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    <indexterm>
-     <primary>BETWEEN</primary>
-    </indexterm>
-    <indexterm>
-     <primary>BETWEEN SYMMETRIC</primary>
-    </indexterm>
-    The <token>BETWEEN</token> predicate simplifies range tests:
-<synopsis>
-<replaceable>a</replaceable> BETWEEN <replaceable>x</replaceable> AND <replaceable>y</replaceable>
-</synopsis>
-    is equivalent to
-<synopsis>
-<replaceable>a</replaceable> &gt;= <replaceable>x</replaceable> AND <replaceable>a</replaceable> &lt;= <replaceable>y</replaceable>
-</synopsis>
-    Notice that <token>BETWEEN</token> treats the endpoint values as included
-    in the range.
-    <literal>BETWEEN SYMMETRIC</literal> is like <literal>BETWEEN</literal>
-    except there is no requirement that the argument to the left of
-    <literal>AND</literal> be less than or equal to the argument on the right.
-    If it is not, those two arguments are automatically swapped, so that
-    a nonempty range is always implied.
-   </para>
-
-   <para>
-    The various variants of <literal>BETWEEN</literal> are implemented in
-    terms of the ordinary comparison operators, and therefore will work for
-    any data type(s) that can be compared.
-   </para>
-
-   <note>
-    <para>
-     The use of <literal>AND</literal> in the <literal>BETWEEN</literal>
-     syntax creates an ambiguity with the use of <literal>AND</literal> as a
-     logical operator.  To resolve this, only a limited set of expression
-     types are allowed as the second argument of a <literal>BETWEEN</literal>
-     clause.  If you need to write a more complex sub-expression
-     in <literal>BETWEEN</literal>, write parentheses around the
-     sub-expression.
-    </para>
-   </note>
-
-   <para>
-    <indexterm>
-     <primary>IS DISTINCT FROM</primary>
-    </indexterm>
-    <indexterm>
-     <primary>IS NOT DISTINCT FROM</primary>
-    </indexterm>
-    Ordinary comparison operators yield null (signifying <quote>unknown</quote>),
-    not true or false, when either input is null.  For example,
-    <literal>7 = NULL</literal> yields null, as does <literal>7 &lt;&gt; NULL</literal>.  When
-    this behavior is not suitable, use the
-    <literal>IS <optional> NOT </optional> DISTINCT FROM</literal> predicates:
-<synopsis>
-<replaceable>a</replaceable> IS DISTINCT FROM <replaceable>b</replaceable>
-<replaceable>a</replaceable> IS NOT DISTINCT FROM <replaceable>b</replaceable>
-</synopsis>
-    For non-null inputs, <literal>IS DISTINCT FROM</literal> is
-    the same as the <literal>&lt;&gt;</literal> operator.  However, if both
-    inputs are null it returns false, and if only one input is
-    null it returns true.  Similarly, <literal>IS NOT DISTINCT
-    FROM</literal> is identical to <literal>=</literal> for non-null
-    inputs, but it returns true when both inputs are null, and false when only
-    one input is null. Thus, these predicates effectively act as though null
-    were a normal data value, rather than <quote>unknown</quote>.
-   </para>
-
-   <para>
-    <indexterm>
-     <primary>IS NULL</primary>
-    </indexterm>
-    <indexterm>
-     <primary>IS NOT NULL</primary>
-    </indexterm>
-    <indexterm>
-     <primary>ISNULL</primary>
-    </indexterm>
-    <indexterm>
-     <primary>NOTNULL</primary>
-    </indexterm>
-    To check whether a value is or is not null, use the predicates:
-<synopsis>
-<replaceable>expression</replaceable> IS NULL
-<replaceable>expression</replaceable> IS NOT NULL
-</synopsis>
-    or the equivalent, but nonstandard, predicates:
-<synopsis>
-<replaceable>expression</replaceable> ISNULL
-<replaceable>expression</replaceable> NOTNULL
-</synopsis>
-    <indexterm><primary>null value</primary><secondary>comparing</secondary></indexterm>
-   </para>
-
-   <para>
-    Do <emphasis>not</emphasis> write
-    <literal><replaceable>expression</replaceable> = NULL</literal>
-    because <literal>NULL</literal> is not <quote>equal to</quote>
-    <literal>NULL</literal>.  (The null value represents an unknown value,
-    and it is not known whether two unknown values are equal.)
-   </para>
-
-  <tip>
-   <para>
-    Some applications might expect that
-    <literal><replaceable>expression</replaceable> = NULL</literal>
-    returns true if <replaceable>expression</replaceable> evaluates to
-    the null value.  It is highly recommended that these applications
-    be modified to comply with the SQL standard. However, if that
-    cannot be done the <xref linkend="guc-transform-null-equals"/>
-    configuration variable is available. If it is enabled,
-    <productname>PostgreSQL</productname> will convert <literal>x =
-    NULL</literal> clauses to <literal>x IS NULL</literal>.
-   </para>
-  </tip>
-
-   <para>
-    If the <replaceable>expression</replaceable> is row-valued, then
-    <literal>IS NULL</literal> is true when the row expression itself is null
-    or when all the row's fields are null, while
-    <literal>IS NOT NULL</literal> is true when the row expression itself is non-null
-    and all the row's fields are non-null.  Because of this behavior,
-    <literal>IS NULL</literal> and <literal>IS NOT NULL</literal> do not always return
-    inverse results for row-valued expressions; in particular, a row-valued
-    expression that contains both null and non-null fields will return false
-    for both tests.  For example:
-
-<programlisting>
-SELECT ROW(1,2.5,'this is a test') = ROW(1, 3, 'not the same');
-
-SELECT ROW(table.*) IS NULL FROM table;  -- detect all-null rows
-
-SELECT ROW(table.*) IS NOT NULL FROM table;  -- detect all-non-null rows
-
-SELECT NOT(ROW(table.*) IS NOT NULL) FROM TABLE; -- detect at least one null in rows
-</programlisting>
-
-    In some cases, it may be preferable to
-    write <replaceable>row</replaceable> <literal>IS DISTINCT FROM NULL</literal>
-    or <replaceable>row</replaceable> <literal>IS NOT DISTINCT FROM NULL</literal>,
-    which will simply check whether the overall row value is null without any
-    additional tests on the row fields.
-   </para>
-
-   <para>
-    <indexterm>
-     <primary>IS TRUE</primary>
-    </indexterm>
-    <indexterm>
-     <primary>IS NOT TRUE</primary>
-    </indexterm>
-    <indexterm>
-     <primary>IS FALSE</primary>
-    </indexterm>
-    <indexterm>
-     <primary>IS NOT FALSE</primary>
-    </indexterm>
-    <indexterm>
-     <primary>IS UNKNOWN</primary>
-    </indexterm>
-    <indexterm>
-     <primary>IS NOT UNKNOWN</primary>
-    </indexterm>
-    Boolean values can also be tested using the predicates
-<synopsis>
-<replaceable>boolean_expression</replaceable> IS TRUE
-<replaceable>boolean_expression</replaceable> IS NOT TRUE
-<replaceable>boolean_expression</replaceable> IS FALSE
-<replaceable>boolean_expression</replaceable> IS NOT FALSE
-<replaceable>boolean_expression</replaceable> IS UNKNOWN
-<replaceable>boolean_expression</replaceable> IS NOT UNKNOWN
-</synopsis>
-    These will always return true or false, never a null value, even when the
-    operand is null.
-    A null input is treated as the logical value <quote>unknown</quote>.
-    Notice that <literal>IS UNKNOWN</literal> and <literal>IS NOT UNKNOWN</literal> are
-    effectively the same as <literal>IS NULL</literal> and
-    <literal>IS NOT NULL</literal>, respectively, except that the input
-    expression must be of Boolean type.
-   </para>
-
-   <para>
-    Some comparison-related functions are also available, as shown in <xref
-    linkend="functions-comparison-func-table"/>.
-   </para>
-
-  <table id="functions-comparison-func-table">
-    <title>Comparison Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>num_nonnulls</primary>
-        </indexterm>
-        <function>num_nonnulls</function> ( <literal>VARIADIC</literal> <type>"any"</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the number of non-null arguments.
-       </para>
-       <para>
-        <literal>num_nonnulls(1, NULL, 2)</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>num_nulls</primary>
-        </indexterm>
-        <function>num_nulls</function> ( <literal>VARIADIC</literal> <type>"any"</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the number of null arguments.
-       </para>
-       <para>
-        <literal>num_nulls(1, NULL, 2)</literal>
-        <returnvalue>1</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  </sect1>
-
-  <sect1 id="functions-math">
-   <title>Mathematical Functions and Operators</title>
-
-   <para>
-    Mathematical operators are provided for many
-    <productname>PostgreSQL</productname> types. For types without
-    standard mathematical conventions
-    (e.g., date/time types) we
-    describe the actual behavior in subsequent sections.
-   </para>
-
-   <para>
-    <xref linkend="functions-math-op-table"/> shows the mathematical
-    operators that are available for the standard numeric types.
-    Unless otherwise noted, operators shown as
-    accepting <replaceable>numeric_type</replaceable> are available for all
-    the types <type>smallint</type>, <type>integer</type>,
-    <type>bigint</type>, <type>numeric</type>, <type>real</type>,
-    and <type>double precision</type>.
-    Operators shown as accepting <replaceable>integral_type</replaceable>
-    are available for the types <type>smallint</type>, <type>integer</type>,
-    and <type>bigint</type>.
-    Except where noted, each form of an operator returns the same data type
-    as its argument(s).  Calls involving multiple argument data types, such
-    as <type>integer</type> <literal>+</literal> <type>numeric</type>,
-    are resolved by using the type appearing later in these lists.
-   </para>
-
-   <table id="functions-math-op-table">
-    <title>Mathematical Operators</title>
-
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Operator
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>numeric_type</replaceable> <literal>+</literal> <replaceable>numeric_type</replaceable>
-        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Addition
-       </para>
-       <para>
-        <literal>2 + 3</literal>
-        <returnvalue>5</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>+</literal> <replaceable>numeric_type</replaceable>
-        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Unary plus (no operation)
-       </para>
-       <para>
-        <literal>+ 3.5</literal>
-        <returnvalue>3.5</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>numeric_type</replaceable> <literal>-</literal> <replaceable>numeric_type</replaceable>
-        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Subtraction
-       </para>
-       <para>
-        <literal>2 - 3</literal>
-        <returnvalue>-1</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>-</literal> <replaceable>numeric_type</replaceable>
-        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Negation
-       </para>
-       <para>
-        <literal>- (-4)</literal>
-        <returnvalue>4</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>numeric_type</replaceable> <literal>*</literal> <replaceable>numeric_type</replaceable>
-        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Multiplication
-       </para>
-       <para>
-        <literal>2 * 3</literal>
-        <returnvalue>6</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>numeric_type</replaceable> <literal>/</literal> <replaceable>numeric_type</replaceable>
-        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Division (for integral types, division truncates the result towards
-        zero)
-       </para>
-       <para>
-        <literal>5.0 / 2</literal>
-        <returnvalue>2.5000000000000000</returnvalue>
-       </para>
-       <para>
-        <literal>5 / 2</literal>
-        <returnvalue>2</returnvalue>
-       </para>
-       <para>
-        <literal>(-5) / 2</literal>
-        <returnvalue>-2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>numeric_type</replaceable> <literal>%</literal> <replaceable>numeric_type</replaceable>
-        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Modulo (remainder); available for <type>smallint</type>,
-        <type>integer</type>, <type>bigint</type>, and <type>numeric</type>
-       </para>
-       <para>
-        <literal>5 % 4</literal>
-        <returnvalue>1</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>numeric</type> <literal>^</literal> <type>numeric</type>
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <type>double precision</type> <literal>^</literal> <type>double precision</type>
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Exponentiation
-       </para>
-       <para>
-        <literal>2 ^ 3</literal>
-        <returnvalue>8</returnvalue>
-       </para>
-       <para>
-        Unlike typical mathematical practice, multiple uses of
-        <literal>^</literal> will associate left to right by default:
-       </para>
-       <para>
-        <literal>2 ^ 3 ^ 3</literal>
-        <returnvalue>512</returnvalue>
-       </para>
-       <para>
-        <literal>2 ^ (3 ^ 3)</literal>
-        <returnvalue>134217728</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>|/</literal> <type>double precision</type>
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Square root
-       </para>
-       <para>
-        <literal>|/ 25.0</literal>
-        <returnvalue>5</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>||/</literal> <type>double precision</type>
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Cube root
-       </para>
-       <para>
-        <literal>||/ 64.0</literal>
-        <returnvalue>4</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>@</literal> <replaceable>numeric_type</replaceable>
-        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Absolute value
-       </para>
-       <para>
-        <literal>@ -5.0</literal>
-        <returnvalue>5.0</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>integral_type</replaceable> <literal>&amp;</literal> <replaceable>integral_type</replaceable>
-        <returnvalue><replaceable>integral_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Bitwise AND
-       </para>
-       <para>
-        <literal>91 &amp; 15</literal>
-        <returnvalue>11</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>integral_type</replaceable> <literal>|</literal> <replaceable>integral_type</replaceable>
-        <returnvalue><replaceable>integral_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Bitwise OR
-       </para>
-       <para>
-        <literal>32 | 3</literal>
-        <returnvalue>35</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>integral_type</replaceable> <literal>#</literal> <replaceable>integral_type</replaceable>
-        <returnvalue><replaceable>integral_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Bitwise exclusive OR
-       </para>
-       <para>
-        <literal>17 # 5</literal>
-        <returnvalue>20</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>~</literal> <replaceable>integral_type</replaceable>
-        <returnvalue><replaceable>integral_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Bitwise NOT
-       </para>
-       <para>
-        <literal>~1</literal>
-        <returnvalue>-2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>integral_type</replaceable> <literal>&lt;&lt;</literal> <type>integer</type>
-        <returnvalue><replaceable>integral_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Bitwise shift left
-       </para>
-       <para>
-        <literal>1 &lt;&lt; 4</literal>
-        <returnvalue>16</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>integral_type</replaceable> <literal>&gt;&gt;</literal> <type>integer</type>
-        <returnvalue><replaceable>integral_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Bitwise shift right
-       </para>
-       <para>
-        <literal>8 &gt;&gt; 2</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-
-     </tbody>
-    </tgroup>
-   </table>
-
-  <para>
-   <xref linkend="functions-math-func-table"/> shows the available
-   mathematical functions.
-   Many of these functions are provided in multiple forms with different
-   argument types.
-   Except where noted, any given form of a function returns the same
-   data type as its argument(s); cross-type cases are resolved in the
-   same way as explained above for operators.
-   The functions working with <type>double precision</type> data are mostly
-   implemented on top of the host system's C library; accuracy and behavior in
-   boundary cases can therefore vary depending on the host system.
-  </para>
-
-   <table id="functions-math-func-table">
-    <title>Mathematical Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>abs</primary>
-        </indexterm>
-        <function>abs</function> ( <replaceable>numeric_type</replaceable> )
-        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Absolute value
-       </para>
-       <para>
-        <literal>abs(-17.4)</literal>
-        <returnvalue>17.4</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>cbrt</primary>
-        </indexterm>
-        <function>cbrt</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Cube root
-       </para>
-       <para>
-        <literal>cbrt(64.0)</literal>
-        <returnvalue>4</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>ceil</primary>
-        </indexterm>
-        <function>ceil</function> ( <type>numeric</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>ceil</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Nearest integer greater than or equal to argument
-       </para>
-       <para>
-        <literal>ceil(42.2)</literal>
-        <returnvalue>43</returnvalue>
-       </para>
-       <para>
-        <literal>ceil(-42.8)</literal>
-        <returnvalue>-42</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>ceiling</primary>
-        </indexterm>
-        <function>ceiling</function> ( <type>numeric</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>ceiling</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Nearest integer greater than or equal to argument (same
-        as <function>ceil</function>)
-       </para>
-       <para>
-        <literal>ceiling(95.3)</literal>
-        <returnvalue>96</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>degrees</primary>
-        </indexterm>
-        <function>degrees</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Converts radians to degrees
-       </para>
-       <para>
-        <literal>degrees(0.5)</literal>
-        <returnvalue>28.64788975654116</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>div</primary>
-        </indexterm>
-        <function>div</function> ( <parameter>y</parameter> <type>numeric</type>,
-        <parameter>x</parameter> <type>numeric</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para>
-        Integer quotient of <parameter>y</parameter>/<parameter>x</parameter>
-        (truncates towards zero)
-       </para>
-       <para>
-        <literal>div(9, 4)</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>erf</primary>
-        </indexterm>
-        <function>erf</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Error function
-       </para>
-       <para>
-        <literal>erf(1.0)</literal>
-        <returnvalue>0.8427007929497149</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>erfc</primary>
-        </indexterm>
-        <function>erfc</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Complementary error function (<literal>1 - erf(x)</literal>, without
-        loss of precision for large inputs)
-       </para>
-       <para>
-        <literal>erfc(1.0)</literal>
-        <returnvalue>0.15729920705028513</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>exp</primary>
-        </indexterm>
-        <function>exp</function> ( <type>numeric</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>exp</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Exponential (<literal>e</literal> raised to the given power)
-       </para>
-       <para>
-        <literal>exp(1.0)</literal>
-        <returnvalue>2.7182818284590452</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm id="function-factorial">
-         <primary>factorial</primary>
-        </indexterm>
-        <function>factorial</function> ( <type>bigint</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para>
-        Factorial
-       </para>
-       <para>
-        <literal>factorial(5)</literal>
-        <returnvalue>120</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>floor</primary>
-        </indexterm>
-        <function>floor</function> ( <type>numeric</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>floor</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Nearest integer less than or equal to argument
-       </para>
-       <para>
-        <literal>floor(42.8)</literal>
-        <returnvalue>42</returnvalue>
-       </para>
-       <para>
-        <literal>floor(-42.8)</literal>
-        <returnvalue>-43</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>gamma</primary>
-        </indexterm>
-        <function>gamma</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Gamma function
-       </para>
-       <para>
-        <literal>gamma(0.5)</literal>
-        <returnvalue>1.772453850905516</returnvalue>
-       </para>
-       <para>
-        <literal>gamma(6)</literal>
-        <returnvalue>120</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>gcd</primary>
-        </indexterm>
-        <function>gcd</function> ( <replaceable>numeric_type</replaceable>, <replaceable>numeric_type</replaceable> )
-        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Greatest common divisor (the largest positive number that divides both
-        inputs with no remainder); returns <literal>0</literal> if both inputs
-        are zero; available for <type>integer</type>, <type>bigint</type>,
-        and <type>numeric</type>
-       </para>
-       <para>
-        <literal>gcd(1071, 462)</literal>
-        <returnvalue>21</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>lcm</primary>
-        </indexterm>
-        <function>lcm</function> ( <replaceable>numeric_type</replaceable>, <replaceable>numeric_type</replaceable> )
-        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Least common multiple (the smallest strictly positive number that is
-        an integral multiple of both inputs); returns <literal>0</literal> if
-        either input is zero; available for <type>integer</type>,
-        <type>bigint</type>, and <type>numeric</type>
-       </para>
-       <para>
-        <literal>lcm(1071, 462)</literal>
-        <returnvalue>23562</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>lgamma</primary>
-        </indexterm>
-        <function>lgamma</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Natural logarithm of the absolute value of the gamma function
-       </para>
-       <para>
-        <literal>lgamma(1000)</literal>
-        <returnvalue>5905.220423209181</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>ln</primary>
-        </indexterm>
-        <function>ln</function> ( <type>numeric</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>ln</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Natural logarithm
-       </para>
-       <para>
-        <literal>ln(2.0)</literal>
-        <returnvalue>0.6931471805599453</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>log</primary>
-        </indexterm>
-        <function>log</function> ( <type>numeric</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>log</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Base 10 logarithm
-       </para>
-       <para>
-        <literal>log(100)</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>log10</primary>
-        </indexterm>
-        <function>log10</function> ( <type>numeric</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>log10</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Base 10 logarithm (same as <function>log</function>)
-       </para>
-       <para>
-        <literal>log10(1000)</literal>
-        <returnvalue>3</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>log</function> ( <parameter>b</parameter> <type>numeric</type>,
-        <parameter>x</parameter> <type>numeric</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para>
-        Logarithm of <parameter>x</parameter> to base <parameter>b</parameter>
-       </para>
-       <para>
-       <literal>log(2.0, 64.0)</literal>
-       <returnvalue>6.0000000000000000</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>min_scale</primary>
-        </indexterm>
-        <function>min_scale</function> ( <type>numeric</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Minimum scale (number of fractional decimal digits) needed
-        to represent the supplied value precisely
-       </para>
-       <para>
-        <literal>min_scale(8.4100)</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>mod</primary>
-        </indexterm>
-        <function>mod</function> ( <parameter>y</parameter> <replaceable>numeric_type</replaceable>,
-        <parameter>x</parameter> <replaceable>numeric_type</replaceable> )
-        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Remainder of <parameter>y</parameter>/<parameter>x</parameter>;
-        available for <type>smallint</type>, <type>integer</type>,
-        <type>bigint</type>, and <type>numeric</type>
-       </para>
-       <para>
-        <literal>mod(9, 4)</literal>
-        <returnvalue>1</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pi</primary>
-        </indexterm>
-        <function>pi</function> (  )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Approximate value of <phrase role="symbol_font">&pi;</phrase>
-       </para>
-       <para>
-        <literal>pi()</literal>
-        <returnvalue>3.141592653589793</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>power</primary>
-        </indexterm>
-        <function>power</function> ( <parameter>a</parameter> <type>numeric</type>,
-        <parameter>b</parameter> <type>numeric</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>power</function> ( <parameter>a</parameter> <type>double precision</type>,
-        <parameter>b</parameter> <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        <parameter>a</parameter> raised to the power of <parameter>b</parameter>
-       </para>
-       <para>
-        <literal>power(9, 3)</literal>
-        <returnvalue>729</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>radians</primary>
-        </indexterm>
-        <function>radians</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Converts degrees to radians
-       </para>
-       <para>
-        <literal>radians(45.0)</literal>
-        <returnvalue>0.7853981633974483</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>round</primary>
-        </indexterm>
-        <function>round</function> ( <type>numeric</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>round</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Rounds to nearest integer.  For <type>numeric</type>, ties are
-        broken by rounding away from zero.  For <type>double precision</type>,
-        the tie-breaking behavior is platform dependent, but
-        <quote>round to nearest even</quote> is the most common rule.
-       </para>
-       <para>
-        <literal>round(42.4)</literal>
-        <returnvalue>42</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>round</function> ( <parameter>v</parameter> <type>numeric</type>, <parameter>s</parameter> <type>integer</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para>
-        Rounds <parameter>v</parameter> to <parameter>s</parameter> decimal
-        places.  Ties are broken by rounding away from zero.
-       </para>
-       <para>
-        <literal>round(42.4382, 2)</literal>
-        <returnvalue>42.44</returnvalue>
-       </para>
-       <para>
-        <literal>round(1234.56, -1)</literal>
-        <returnvalue>1230</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>scale</primary>
-        </indexterm>
-        <function>scale</function> ( <type>numeric</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Scale of the argument (the number of decimal digits in the fractional part)
-       </para>
-       <para>
-        <literal>scale(8.4100)</literal>
-        <returnvalue>4</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>sign</primary>
-        </indexterm>
-        <function>sign</function> ( <type>numeric</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>sign</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Sign of the argument (-1, 0, or +1)
-       </para>
-       <para>
-        <literal>sign(-8.4)</literal>
-        <returnvalue>-1</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>sqrt</primary>
-        </indexterm>
-         <function>sqrt</function> ( <type>numeric</type> )
-         <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-         <function>sqrt</function> ( <type>double precision</type> )
-         <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Square root
-       </para>
-       <para>
-        <literal>sqrt(2)</literal>
-        <returnvalue>1.4142135623730951</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>trim_scale</primary>
-        </indexterm>
-        <function>trim_scale</function> ( <type>numeric</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para>
-        Reduces the value's scale (number of fractional decimal digits) by
-        removing trailing zeroes
-       </para>
-       <para>
-        <literal>trim_scale(8.4100)</literal>
-        <returnvalue>8.41</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>trunc</primary>
-        </indexterm>
-        <function>trunc</function> ( <type>numeric</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>trunc</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Truncates to integer (towards zero)
-       </para>
-       <para>
-        <literal>trunc(42.8)</literal>
-        <returnvalue>42</returnvalue>
-       </para>
-       <para>
-        <literal>trunc(-42.8)</literal>
-        <returnvalue>-42</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>trunc</function> ( <parameter>v</parameter> <type>numeric</type>, <parameter>s</parameter> <type>integer</type> )
-       <returnvalue>numeric</returnvalue>
-       </para>
-       <para>
-        Truncates <parameter>v</parameter> to <parameter>s</parameter>
-        decimal places
-       </para>
-       <para>
-        <literal>trunc(42.4382, 2)</literal>
-        <returnvalue>42.43</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>width_bucket</primary>
-        </indexterm>
-        <function>width_bucket</function> ( <parameter>operand</parameter> <type>numeric</type>, <parameter>low</parameter> <type>numeric</type>, <parameter>high</parameter> <type>numeric</type>, <parameter>count</parameter> <type>integer</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>width_bucket</function> ( <parameter>operand</parameter> <type>double precision</type>, <parameter>low</parameter> <type>double precision</type>, <parameter>high</parameter> <type>double precision</type>, <parameter>count</parameter> <type>integer</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the number of the bucket in
-        which <parameter>operand</parameter> falls in a histogram
-        having <parameter>count</parameter> equal-width buckets spanning the
-        range <parameter>low</parameter> to <parameter>high</parameter>.
-        The buckets have inclusive lower bounds and exclusive upper bounds.
-        Returns <literal>0</literal> for an input less
-        than <parameter>low</parameter>,
-        or <literal><parameter>count</parameter>+1</literal> for an input
-        greater than or equal to <parameter>high</parameter>.
-        If <parameter>low</parameter> &gt; <parameter>high</parameter>,
-        the behavior is mirror-reversed, with bucket <literal>1</literal>
-        now being the one just below <parameter>low</parameter>, and the
-        inclusive bounds now being on the upper side.
-       </para>
-       <para>
-        <literal>width_bucket(5.35, 0.024, 10.06, 5)</literal>
-        <returnvalue>3</returnvalue>
-       </para>
-       <para>
-        <literal>width_bucket(9, 10, 0, 10)</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>width_bucket</function> ( <parameter>operand</parameter> <type>anycompatible</type>, <parameter>thresholds</parameter> <type>anycompatiblearray</type> )
-       <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the number of the bucket in
-        which <parameter>operand</parameter> falls given an array listing the
-        inclusive lower bounds of the buckets.
-        Returns <literal>0</literal> for an input less than the first lower
-        bound.  <parameter>operand</parameter> and the array elements can be
-        of any type having standard comparison operators.
-        The <parameter>thresholds</parameter> array <emphasis>must be
-        sorted</emphasis>, smallest first, or unexpected results will be
-        obtained.
-       </para>
-       <para>
-        <literal>width_bucket(now(), array['yesterday', 'today', 'tomorrow']::timestamptz[])</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <para>
-    <xref linkend="functions-math-random-table"/> shows functions for
-    generating random numbers.
-  </para>
-
-   <table id="functions-math-random-table">
-    <title>Random Functions</title>
-
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>random</primary>
-        </indexterm>
-        <function>random</function> ( )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Returns a random value in the range 0.0 &lt;= x &lt; 1.0
-       </para>
-       <para>
-        <literal>random()</literal>
-        <returnvalue>0.897124072839091</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>random</primary>
-        </indexterm>
-        <function>random</function> ( <parameter>min</parameter> <type>integer</type>, <parameter>max</parameter> <type>integer</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>random</function> ( <parameter>min</parameter> <type>bigint</type>, <parameter>max</parameter> <type>bigint</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>random</function> ( <parameter>min</parameter> <type>numeric</type>, <parameter>max</parameter> <type>numeric</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para>
-        Returns a random value in the range
-        <parameter>min</parameter> &lt;= x &lt;= <parameter>max</parameter>.
-        For type <type>numeric</type>, the result will have the same number of
-        fractional decimal digits as <parameter>min</parameter> or
-        <parameter>max</parameter>, whichever has more.
-       </para>
-       <para>
-        <literal>random(1, 10)</literal>
-        <returnvalue>7</returnvalue>
-       </para>
-       <para>
-        <literal>random(-0.499, 0.499)</literal>
-        <returnvalue>0.347</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>random_normal</primary>
-        </indexterm>
-
-         <function>random_normal</function> (
-         <optional> <parameter>mean</parameter> <type>double precision</type>
-         <optional>, <parameter>stddev</parameter> <type>double precision</type> </optional></optional> )
-         <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Returns a random value from the normal distribution with the given
-        parameters; <parameter>mean</parameter> defaults to 0.0
-        and <parameter>stddev</parameter> defaults to 1.0
-       </para>
-       <para>
-        <literal>random_normal(0.0, 1.0)</literal>
-        <returnvalue>0.051285419</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>setseed</primary>
-        </indexterm>
-        <function>setseed</function> ( <type>double precision</type> )
-        <returnvalue>void</returnvalue>
-       </para>
-       <para>
-        Sets the seed for subsequent <literal>random()</literal> and
-        <literal>random_normal()</literal> calls;
-        argument must be between -1.0 and 1.0, inclusive
-       </para>
-       <para>
-        <literal>setseed(0.12345)</literal>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <para>
-   The <function>random()</function> and <function>random_normal()</function>
-   functions listed in <xref linkend="functions-math-random-table"/> use a
-   deterministic pseudo-random number generator.
-   It is fast but not suitable for cryptographic
-   applications; see the <xref linkend="pgcrypto"/> module for a more
-   secure alternative.
-   If <function>setseed()</function> is called, the series of results of
-   subsequent calls to these functions in the current session
-   can be repeated by re-issuing <function>setseed()</function> with the same
-   argument.
-   Without any prior <function>setseed()</function> call in the same
-   session, the first call to any of these functions obtains a seed
-   from a platform-dependent source of random bits.
-  </para>
-
-  <para>
-   <xref linkend="functions-math-trig-table"/> shows the
-   available trigonometric functions.  Each of these functions comes in
-   two variants, one that measures angles in radians and one that
-   measures angles in degrees.
-  </para>
-
-   <table id="functions-math-trig-table">
-    <title>Trigonometric Functions</title>
-
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>acos</primary>
-        </indexterm>
-        <function>acos</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Inverse cosine, result in radians
-       </para>
-       <para>
-        <literal>acos(1)</literal>
-        <returnvalue>0</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>acosd</primary>
-        </indexterm>
-        <function>acosd</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Inverse cosine, result in degrees
-       </para>
-       <para>
-        <literal>acosd(0.5)</literal>
-        <returnvalue>60</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>asin</primary>
-        </indexterm>
-        <function>asin</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Inverse sine, result in radians
-       </para>
-       <para>
-        <literal>asin(1)</literal>
-        <returnvalue>1.5707963267948966</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>asind</primary>
-        </indexterm>
-        <function>asind</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Inverse sine, result in degrees
-       </para>
-       <para>
-        <literal>asind(0.5)</literal>
-        <returnvalue>30</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>atan</primary>
-        </indexterm>
-        <function>atan</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Inverse tangent, result in radians
-       </para>
-       <para>
-        <literal>atan(1)</literal>
-        <returnvalue>0.7853981633974483</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>atand</primary>
-        </indexterm>
-        <function>atand</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Inverse tangent, result in degrees
-       </para>
-       <para>
-        <literal>atand(1)</literal>
-        <returnvalue>45</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>atan2</primary>
-        </indexterm>
-        <function>atan2</function> ( <parameter>y</parameter> <type>double precision</type>,
-        <parameter>x</parameter> <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Inverse tangent of
-        <parameter>y</parameter>/<parameter>x</parameter>,
-        result in radians
-       </para>
-       <para>
-        <literal>atan2(1, 0)</literal>
-        <returnvalue>1.5707963267948966</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>atan2d</primary>
-        </indexterm>
-        <function>atan2d</function> ( <parameter>y</parameter> <type>double precision</type>,
-        <parameter>x</parameter> <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Inverse tangent of
-        <parameter>y</parameter>/<parameter>x</parameter>,
-        result in degrees
-       </para>
-       <para>
-        <literal>atan2d(1, 0)</literal>
-        <returnvalue>90</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>cos</primary>
-        </indexterm>
-        <function>cos</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Cosine, argument in radians
-       </para>
-       <para>
-        <literal>cos(0)</literal>
-        <returnvalue>1</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>cosd</primary>
-        </indexterm>
-        <function>cosd</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Cosine, argument in degrees
-       </para>
-       <para>
-        <literal>cosd(60)</literal>
-        <returnvalue>0.5</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>cot</primary>
-        </indexterm>
-        <function>cot</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Cotangent, argument in radians
-       </para>
-       <para>
-        <literal>cot(0.5)</literal>
-        <returnvalue>1.830487721712452</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>cotd</primary>
-        </indexterm>
-        <function>cotd</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Cotangent, argument in degrees
-       </para>
-       <para>
-        <literal>cotd(45)</literal>
-        <returnvalue>1</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>sin</primary>
-        </indexterm>
-        <function>sin</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Sine, argument in radians
-       </para>
-       <para>
-        <literal>sin(1)</literal>
-        <returnvalue>0.8414709848078965</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>sind</primary>
-        </indexterm>
-        <function>sind</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Sine, argument in degrees
-       </para>
-       <para>
-        <literal>sind(30)</literal>
-        <returnvalue>0.5</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>tan</primary>
-        </indexterm>
-        <function>tan</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Tangent, argument in radians
-       </para>
-       <para>
-        <literal>tan(1)</literal>
-        <returnvalue>1.5574077246549023</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>tand</primary>
-        </indexterm>
-        <function>tand</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Tangent, argument in degrees
-       </para>
-       <para>
-        <literal>tand(45)</literal>
-        <returnvalue>1</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <note>
-   <para>
-    Another way to work with angles measured in degrees is to use the unit
-    transformation functions <literal><function>radians()</function></literal>
-    and <literal><function>degrees()</function></literal> shown earlier.
-    However, using the degree-based trigonometric functions is preferred,
-    as that way avoids round-off error for special cases such
-    as <literal>sind(30)</literal>.
-   </para>
-  </note>
-
-  <para>
-   <xref linkend="functions-math-hyp-table"/> shows the
-   available hyperbolic functions.
-  </para>
-
-  <table id="functions-math-hyp-table">
-    <title>Hyperbolic Functions</title>
-
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>sinh</primary>
-        </indexterm>
-        <function>sinh</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Hyperbolic sine
-       </para>
-       <para>
-        <literal>sinh(1)</literal>
-        <returnvalue>1.1752011936438014</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>cosh</primary>
-        </indexterm>
-        <function>cosh</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Hyperbolic cosine
-       </para>
-       <para>
-        <literal>cosh(0)</literal>
-        <returnvalue>1</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>tanh</primary>
-        </indexterm>
-        <function>tanh</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Hyperbolic tangent
-       </para>
-       <para>
-        <literal>tanh(1)</literal>
-        <returnvalue>0.7615941559557649</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>asinh</primary>
-        </indexterm>
-        <function>asinh</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Inverse hyperbolic sine
-       </para>
-       <para>
-        <literal>asinh(1)</literal>
-        <returnvalue>0.881373587019543</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>acosh</primary>
-        </indexterm>
-        <function>acosh</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Inverse hyperbolic cosine
-       </para>
-       <para>
-        <literal>acosh(1)</literal>
-        <returnvalue>0</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>atanh</primary>
-        </indexterm>
-        <function>atanh</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Inverse hyperbolic tangent
-       </para>
-       <para>
-        <literal>atanh(0.5)</literal>
-        <returnvalue>0.5493061443340548</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  </sect1>
-
-
-  <sect1 id="functions-string">
-   <title>String Functions and Operators</title>
-
-   <para>
-    This section describes functions and operators for examining and
-    manipulating string values.  Strings in this context include values
-    of the types <type>character</type>, <type>character varying</type>,
-    and <type>text</type>.  Except where noted, these functions and operators
-    are declared to accept and return type <type>text</type>.  They will
-    interchangeably accept <type>character varying</type> arguments.
-    Values of type <type>character</type> will be converted
-    to <type>text</type> before the function or operator is applied, resulting
-    in stripping any trailing spaces in the <type>character</type> value.
-   </para>
-
-   <para>
-    <acronym>SQL</acronym> defines some string functions that use
-    key words, rather than commas, to separate
-    arguments.  Details are in
-    <xref linkend="functions-string-sql"/>.
-    <productname>PostgreSQL</productname> also provides versions of these functions
-    that use the regular function invocation syntax
-    (see <xref linkend="functions-string-other"/>).
-   </para>
-
-   <note>
-    <para>
-     The string concatenation operator (<literal>||</literal>) will accept
-     non-string input, so long as at least one input is of string type, as shown
-     in <xref linkend="functions-string-sql"/>.  For other cases, inserting an
-     explicit coercion to <type>text</type> can be used to have non-string input
-     accepted.
-    </para>
-   </note>
-
-   <table id="functions-string-sql">
-    <title><acronym>SQL</acronym> String Functions and Operators</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function/Operator
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>character string</primary>
-         <secondary>concatenation</secondary>
-        </indexterm>
-        <type>text</type> <literal>||</literal> <type>text</type>
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Concatenates the two strings.
-       </para>
-       <para>
-        <literal>'Post' || 'greSQL'</literal>
-        <returnvalue>PostgreSQL</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>text</type> <literal>||</literal> <type>anynonarray</type>
-        <returnvalue>text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <type>anynonarray</type> <literal>||</literal> <type>text</type>
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts the non-string input to text, then concatenates the two
-        strings.  (The non-string input cannot be of an array type, because
-        that would create ambiguity with the array <literal>||</literal>
-        operators.  If you want to concatenate an array's text equivalent,
-        cast it to <type>text</type> explicitly.)
-       </para>
-       <para>
-        <literal>'Value: ' || 42</literal>
-        <returnvalue>Value: 42</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>btrim</primary>
-        </indexterm>
-        <function>btrim</function> ( <parameter>string</parameter> <type>text</type>
-        <optional>, <parameter>characters</parameter> <type>text</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Removes the longest string containing only characters
-        in <parameter>characters</parameter> (a space by default)
-        from the start and end of <parameter>string</parameter>.
-       </para>
-       <para>
-        <literal>btrim('xyxtrimyyx', 'xyz')</literal>
-        <returnvalue>trim</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>normalized</primary>
-        </indexterm>
-        <indexterm>
-         <primary>Unicode normalization</primary>
-        </indexterm>
-         <type>text</type> <literal>IS</literal> <optional><literal>NOT</literal></optional> <optional><parameter>form</parameter></optional> <literal>NORMALIZED</literal>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Checks whether the string is in the specified Unicode normalization
-        form.  The optional <parameter>form</parameter> key word specifies the
-        form: <literal>NFC</literal> (the default), <literal>NFD</literal>,
-        <literal>NFKC</literal>, or <literal>NFKD</literal>.  This expression can
-        only be used when the server encoding is <literal>UTF8</literal>.  Note
-        that checking for normalization using this expression is often faster
-        than normalizing possibly already normalized strings.
-       </para>
-       <para>
-        <literal>U&amp;'\0061\0308bc' IS NFD NORMALIZED</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>bit_length</primary>
-        </indexterm>
-        <function>bit_length</function> ( <type>text</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns number of bits in the string (8
-        times the <function>octet_length</function>).
-       </para>
-       <para>
-        <literal>bit_length('jose')</literal>
-        <returnvalue>32</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>char_length</primary>
-        </indexterm>
-        <indexterm>
-         <primary>character string</primary>
-         <secondary>length</secondary>
-        </indexterm>
-        <indexterm>
-         <primary>length</primary>
-         <secondary sortas="character string">of a character string</secondary>
-         <see>character string, length</see>
-        </indexterm>
-        <function>char_length</function> ( <type>text</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>character_length</primary>
-        </indexterm>
-        <function>character_length</function> ( <type>text</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns number of characters in the string.
-       </para>
-       <para>
-        <literal>char_length('jos&eacute;')</literal>
-        <returnvalue>4</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm id="function-lower">
-         <primary>lower</primary>
-        </indexterm>
-        <function>lower</function> ( <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts the string to all lower case, according to the rules of the
-        database's locale.
-       </para>
-       <para>
-        <literal>lower('TOM')</literal>
-        <returnvalue>tom</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>lpad</primary>
-        </indexterm>
-        <function>lpad</function> ( <parameter>string</parameter> <type>text</type>,
-        <parameter>length</parameter> <type>integer</type>
-        <optional>, <parameter>fill</parameter> <type>text</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Extends the <parameter>string</parameter> to length
-        <parameter>length</parameter> by prepending the characters
-        <parameter>fill</parameter> (a space by default).  If the
-        <parameter>string</parameter> is already longer than
-        <parameter>length</parameter> then it is truncated (on the right).
-       </para>
-       <para>
-        <literal>lpad('hi', 5, 'xy')</literal>
-        <returnvalue>xyxhi</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>ltrim</primary>
-        </indexterm>
-        <function>ltrim</function> ( <parameter>string</parameter> <type>text</type>
-        <optional>, <parameter>characters</parameter> <type>text</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Removes the longest string containing only characters in
-        <parameter>characters</parameter> (a space by default) from the start of
-        <parameter>string</parameter>.
-       </para>
-       <para>
-        <literal>ltrim('zzzytest', 'xyz')</literal>
-        <returnvalue>test</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm id="function-normalize">
-         <primary>normalize</primary>
-        </indexterm>
-        <indexterm>
-         <primary>Unicode normalization</primary>
-        </indexterm>
-        <function>normalize</function> ( <type>text</type>
-        <optional>, <parameter>form</parameter> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts the string to the specified Unicode
-        normalization form.  The optional <parameter>form</parameter> key word
-        specifies the form: <literal>NFC</literal> (the default),
-        <literal>NFD</literal>, <literal>NFKC</literal>, or
-        <literal>NFKD</literal>.  This function can only be used when the
-        server encoding is <literal>UTF8</literal>.
-       </para>
-       <para>
-        <literal>normalize(U&amp;'\0061\0308bc', NFC)</literal>
-        <returnvalue>U&amp;'\00E4bc'</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>octet_length</primary>
-        </indexterm>
-        <function>octet_length</function> ( <type>text</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns number of bytes in the string.
-       </para>
-       <para>
-        <literal>octet_length('jos&eacute;')</literal>
-        <returnvalue>5</returnvalue> (if server encoding is UTF8)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>octet_length</primary>
-        </indexterm>
-        <function>octet_length</function> ( <type>character</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns number of bytes in the string.  Since this version of the
-        function accepts type <type>character</type> directly, it will not
-        strip trailing spaces.
-       </para>
-       <para>
-        <literal>octet_length('abc '::character(4))</literal>
-        <returnvalue>4</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>overlay</primary>
-        </indexterm>
-        <function>overlay</function> ( <parameter>string</parameter> <type>text</type> <literal>PLACING</literal> <parameter>newsubstring</parameter> <type>text</type> <literal>FROM</literal> <parameter>start</parameter> <type>integer</type> <optional> <literal>FOR</literal> <parameter>count</parameter> <type>integer</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Replaces the substring of <parameter>string</parameter> that starts at
-        the <parameter>start</parameter>'th character and extends
-        for <parameter>count</parameter> characters
-        with <parameter>newsubstring</parameter>.
-        If <parameter>count</parameter> is omitted, it defaults to the length
-        of <parameter>newsubstring</parameter>.
-       </para>
-       <para>
-        <literal>overlay('Txxxxas' placing 'hom' from 2 for 4)</literal>
-        <returnvalue>Thomas</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>position</primary>
-        </indexterm>
-        <function>position</function> ( <parameter>substring</parameter> <type>text</type> <literal>IN</literal> <parameter>string</parameter> <type>text</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns first starting index of the specified
-        <parameter>substring</parameter> within
-        <parameter>string</parameter>, or zero if it's not present.
-       </para>
-       <para>
-        <literal>position('om' in 'Thomas')</literal>
-        <returnvalue>3</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>rpad</primary>
-        </indexterm>
-        <function>rpad</function> ( <parameter>string</parameter> <type>text</type>,
-        <parameter>length</parameter> <type>integer</type>
-        <optional>, <parameter>fill</parameter> <type>text</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Extends the <parameter>string</parameter> to length
-        <parameter>length</parameter> by appending the characters
-        <parameter>fill</parameter> (a space by default).  If the
-        <parameter>string</parameter> is already longer than
-        <parameter>length</parameter> then it is truncated.
-       </para>
-       <para>
-        <literal>rpad('hi', 5, 'xy')</literal>
-        <returnvalue>hixyx</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>rtrim</primary>
-        </indexterm>
-        <function>rtrim</function> ( <parameter>string</parameter> <type>text</type>
-         <optional>, <parameter>characters</parameter> <type>text</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Removes the longest string containing only characters in
-        <parameter>characters</parameter> (a space by default) from the end of
-        <parameter>string</parameter>.
-       </para>
-       <para>
-        <literal>rtrim('testxxzx', 'xyz')</literal>
-        <returnvalue>test</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>substring</primary>
-        </indexterm>
-        <function>substring</function> ( <parameter>string</parameter> <type>text</type> <optional> <literal>FROM</literal> <parameter>start</parameter> <type>integer</type> </optional> <optional> <literal>FOR</literal> <parameter>count</parameter> <type>integer</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Extracts the substring of <parameter>string</parameter> starting at
-        the <parameter>start</parameter>'th character if that is specified,
-        and stopping after <parameter>count</parameter> characters if that is
-        specified.  Provide at least one of <parameter>start</parameter>
-        and <parameter>count</parameter>.
-       </para>
-       <para>
-        <literal>substring('Thomas' from 2 for 3)</literal>
-        <returnvalue>hom</returnvalue>
-       </para>
-       <para>
-        <literal>substring('Thomas' from 3)</literal>
-        <returnvalue>omas</returnvalue>
-       </para>
-       <para>
-        <literal>substring('Thomas' for 2)</literal>
-        <returnvalue>Th</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>substring</function> ( <parameter>string</parameter> <type>text</type> <literal>FROM</literal> <parameter>pattern</parameter> <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Extracts the first substring matching POSIX regular expression; see
-        <xref linkend="functions-posix-regexp"/>.
-       </para>
-       <para>
-        <literal>substring('Thomas' from '...$')</literal>
-        <returnvalue>mas</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>substring</function> ( <parameter>string</parameter> <type>text</type> <literal>SIMILAR</literal> <parameter>pattern</parameter> <type>text</type> <literal>ESCAPE</literal> <parameter>escape</parameter> <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>substring</function> ( <parameter>string</parameter> <type>text</type> <literal>FROM</literal> <parameter>pattern</parameter> <type>text</type> <literal>FOR</literal> <parameter>escape</parameter> <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Extracts the first substring matching <acronym>SQL</acronym> regular expression;
-        see <xref linkend="functions-similarto-regexp"/>.  The first form has
-        been specified since SQL:2003; the second form was only in SQL:1999
-        and should be considered obsolete.
-       </para>
-       <para>
-        <literal>substring('Thomas' similar '%#"o_a#"_' escape '#')</literal>
-        <returnvalue>oma</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>trim</primary>
-        </indexterm>
-        <function>trim</function> ( <optional> <literal>LEADING</literal> | <literal>TRAILING</literal> | <literal>BOTH</literal> </optional>
-        <optional> <parameter>characters</parameter> <type>text</type> </optional> <literal>FROM</literal>
-        <parameter>string</parameter> <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Removes the longest string containing only characters in
-        <parameter>characters</parameter> (a space by default) from the
-        start, end, or both ends (<literal>BOTH</literal> is the default)
-        of <parameter>string</parameter>.
-       </para>
-       <para>
-        <literal>trim(both 'xyz' from 'yxTomxx')</literal>
-        <returnvalue>Tom</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>trim</function> ( <optional> <literal>LEADING</literal> | <literal>TRAILING</literal> | <literal>BOTH</literal> </optional> <optional> <literal>FROM</literal> </optional>
-        <parameter>string</parameter> <type>text</type> <optional>,
-        <parameter>characters</parameter> <type>text</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        This is a non-standard syntax for <function>trim()</function>.
-       </para>
-       <para>
-        <literal>trim(both from 'yxTomxx', 'xyz')</literal>
-        <returnvalue>Tom</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>unicode_assigned</primary>
-        </indexterm>
-        <function>unicode_assigned</function> ( <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Returns <literal>true</literal> if all characters in the string are
-        assigned Unicode codepoints; <literal>false</literal> otherwise. This
-        function can only be used when the server encoding is
-        <literal>UTF8</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>upper</primary>
-        </indexterm>
-        <function>upper</function> ( <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts the string to all upper case, according to the rules of the
-        database's locale.
-       </para>
-       <para>
-        <literal>upper('tom')</literal>
-        <returnvalue>TOM</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    Additional string manipulation functions and operators are available
-    and are listed in <xref linkend="functions-string-other"/>.  (Some of
-    these are used internally to implement
-    the <acronym>SQL</acronym>-standard string functions listed in
-    <xref linkend="functions-string-sql"/>.)
-    There are also pattern-matching operators, which are described in
-    <xref linkend="functions-matching"/>, and operators for full-text
-    search, which are described in <xref linkend="textsearch"/>.
-   </para>
-
-   <table id="functions-string-other">
-    <title>Other String Functions and Operators</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function/Operator
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>character string</primary>
-         <secondary>prefix test</secondary>
-        </indexterm>
-        <type>text</type> <literal>^@</literal> <type>text</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Returns true if the first string starts with the second string
-        (equivalent to the <function>starts_with()</function> function).
-       </para>
-       <para>
-        <literal>'alphabet' ^@ 'alph'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>ascii</primary>
-        </indexterm>
-        <function>ascii</function> ( <type>text</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the numeric code of the first character of the argument.
-        In <acronym>UTF8</acronym> encoding, returns the Unicode code point
-        of the character.  In other multibyte encodings, the argument must
-        be an <acronym>ASCII</acronym> character.
-       </para>
-       <para>
-        <literal>ascii('x')</literal>
-        <returnvalue>120</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>chr</primary>
-        </indexterm>
-        <function>chr</function> ( <type>integer</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the character with the given code. In <acronym>UTF8</acronym>
-        encoding the argument is treated as a Unicode code point. In other
-        multibyte encodings the argument must designate
-        an <acronym>ASCII</acronym> character.  <literal>chr(0)</literal> is
-        disallowed because text data types cannot store that character.
-      </para>
-      <para>
-        <literal>chr(65)</literal>
-        <returnvalue>A</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>concat</primary>
-        </indexterm>
-        <function>concat</function> ( <parameter>val1</parameter> <type>"any"</type>
-         <optional>, <parameter>val2</parameter> <type>"any"</type> <optional>, ...</optional> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Concatenates the text representations of all the arguments.
-        NULL arguments are ignored.
-       </para>
-       <para>
-        <literal>concat('abcde', 2, NULL, 22)</literal>
-        <returnvalue>abcde222</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>concat_ws</primary>
-        </indexterm>
-        <function>concat_ws</function> ( <parameter>sep</parameter> <type>text</type>,
-        <parameter>val1</parameter> <type>"any"</type>
-        <optional>, <parameter>val2</parameter> <type>"any"</type> <optional>, ...</optional> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Concatenates all but the first argument, with separators. The first
-        argument is used as the separator string, and should not be NULL.
-        Other NULL arguments are ignored.
-       </para>
-       <para>
-        <literal>concat_ws(',', 'abcde', 2, NULL, 22)</literal>
-        <returnvalue>abcde,2,22</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>format</primary>
-        </indexterm>
-        <function>format</function> ( <parameter>formatstr</parameter> <type>text</type>
-        <optional>, <parameter>formatarg</parameter> <type>"any"</type> <optional>, ...</optional> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-         Formats arguments according to a format string;
-         see <xref linkend="functions-string-format"/>.
-         This function is similar to the C function <function>sprintf</function>.
-       </para>
-       <para>
-        <literal>format('Hello %s, %1$s', 'World')</literal>
-        <returnvalue>Hello World, World</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>initcap</primary>
-        </indexterm>
-        <function>initcap</function> ( <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts the first letter of each word to upper case and the
-        rest to lower case. Words are sequences of alphanumeric
-        characters separated by non-alphanumeric characters.
-       </para>
-       <para>
-        <literal>initcap('hi THOMAS')</literal>
-        <returnvalue>Hi Thomas</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>casefold</primary>
-        </indexterm>
-        <function>casefold</function> ( <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Performs case folding of the input string according to the collation.
-        Case folding is similar to case conversion, but the purpose of case
-        folding is to facilitate case-insensitive matching of strings,
-        whereas the purpose of case conversion is to convert to a particular
-        cased form.  This function can only be used when the server encoding
-        is <literal>UTF8</literal>.
-       </para>
-       <para>
-        Ordinarily, case folding simply converts to lowercase, but there may
-        be exceptions depending on the collation.  For instance, some
-        characters have more than two lowercase variants, or fold to uppercase.
-       </para>
-       <para>
-        Case folding may change the length of the string.  For instance, in
-        the <literal>PG_UNICODE_FAST</literal> collation, <literal>ß</literal>
-        (U+00DF) folds to <literal>ss</literal>.
-       </para>
-       <para>
-        <function>casefold</function> can be used for Unicode Default Caseless
-        Matching.  It does not always preserve the normalized form of the
-        input string (see <xref linkend="function-normalize"/>).
-       </para>
-       <para>
-        The <literal>libc</literal> provider doesn't support case folding, so
-        <function>casefold</function> is identical to <xref
-        linkend="function-lower"/>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>left</primary>
-        </indexterm>
-        <function>left</function> ( <parameter>string</parameter> <type>text</type>,
-        <parameter>n</parameter> <type>integer</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns first <parameter>n</parameter> characters in the
-        string, or when <parameter>n</parameter> is negative, returns
-        all but last |<parameter>n</parameter>| characters.
-       </para>
-       <para>
-        <literal>left('abcde', 2)</literal>
-        <returnvalue>ab</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>length</primary>
-        </indexterm>
-        <function>length</function> ( <type>text</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the number of characters in the string.
-       </para>
-       <para>
-        <literal>length('jose')</literal>
-        <returnvalue>4</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>md5</primary>
-        </indexterm>
-        <function>md5</function> ( <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Computes the MD5 <link linkend="functions-hash-note">hash</link> of
-        the argument, with the result written in hexadecimal.
-       </para>
-       <para>
-        <literal>md5('abc')</literal>
-        <returnvalue>900150983cd24fb0&zwsp;d6963f7d28e17f72</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>parse_ident</primary>
-        </indexterm>
-        <function>parse_ident</function> ( <parameter>qualified_identifier</parameter> <type>text</type>
-        <optional>, <parameter>strict_mode</parameter> <type>boolean</type> <literal>DEFAULT</literal> <literal>true</literal> </optional> )
-        <returnvalue>text[]</returnvalue>
-       </para>
-       <para>
-        Splits <parameter>qualified_identifier</parameter> into an array of
-        identifiers, removing any quoting of individual identifiers.  By
-        default, extra characters after the last identifier are considered an
-        error; but if the second parameter is <literal>false</literal>, then such
-        extra characters are ignored. (This behavior is useful for parsing
-        names for objects like functions.) Note that this function does not
-        truncate over-length identifiers. If you want truncation you can cast
-        the result to <type>name[]</type>.
-       </para>
-       <para>
-        <literal>parse_ident('"SomeSchema".someTable')</literal>
-        <returnvalue>{SomeSchema,sometable}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_client_encoding</primary>
-        </indexterm>
-        <function>pg_client_encoding</function> ( )
-        <returnvalue>name</returnvalue>
-       </para>
-       <para>
-        Returns current client encoding name.
-       </para>
-       <para>
-        <literal>pg_client_encoding()</literal>
-        <returnvalue>UTF8</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>quote_ident</primary>
-        </indexterm>
-        <function>quote_ident</function> ( <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the given string suitably quoted to be used as an identifier
-        in an <acronym>SQL</acronym> statement string.
-        Quotes are added only if necessary (i.e., if the string contains
-        non-identifier characters or would be case-folded).
-        Embedded quotes are properly doubled.
-        See also <xref linkend="plpgsql-quote-literal-example"/>.
-       </para>
-       <para>
-        <literal>quote_ident('Foo bar')</literal>
-        <returnvalue>"Foo bar"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>quote_literal</primary>
-        </indexterm>
-        <function>quote_literal</function> ( <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the given string suitably quoted to be used as a string literal
-        in an <acronym>SQL</acronym> statement string.
-        Embedded single-quotes and backslashes are properly doubled.
-        Note that <function>quote_literal</function> returns null on null
-        input; if the argument might be null,
-        <function>quote_nullable</function> is often more suitable.
-        See also <xref linkend="plpgsql-quote-literal-example"/>.
-       </para>
-       <para>
-        <literal>quote_literal(E'O\'Reilly')</literal>
-        <returnvalue>'O''Reilly'</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>quote_literal</function> ( <type>anyelement</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts the given value to text and then quotes it as a literal.
-        Embedded single-quotes and backslashes are properly doubled.
-       </para>
-       <para>
-        <literal>quote_literal(42.5)</literal>
-        <returnvalue>'42.5'</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>quote_nullable</primary>
-        </indexterm>
-        <function>quote_nullable</function> ( <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the given string suitably quoted to be used as a string literal
-        in an <acronym>SQL</acronym> statement string; or, if the argument
-        is null, returns <literal>NULL</literal>.
-        Embedded single-quotes and backslashes are properly doubled.
-        See also <xref linkend="plpgsql-quote-literal-example"/>.
-       </para>
-       <para>
-        <literal>quote_nullable(NULL)</literal>
-        <returnvalue>NULL</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>quote_nullable</function> ( <type>anyelement</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts the given value to text and then quotes it as a literal;
-        or, if the argument is null, returns <literal>NULL</literal>.
-        Embedded single-quotes and backslashes are properly doubled.
-       </para>
-       <para>
-        <literal>quote_nullable(42.5)</literal>
-        <returnvalue>'42.5'</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regexp_count</primary>
-        </indexterm>
-        <function>regexp_count</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type>
-         <optional>, <parameter>start</parameter> <type>integer</type>
-         <optional>, <parameter>flags</parameter> <type>text</type> </optional> </optional> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the number of times the POSIX regular
-        expression <parameter>pattern</parameter> matches in
-        the <parameter>string</parameter>; see
-        <xref linkend="functions-posix-regexp"/>.
-       </para>
-       <para>
-        <literal>regexp_count('123456789012', '\d\d\d', 2)</literal>
-        <returnvalue>3</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regexp_instr</primary>
-        </indexterm>
-        <function>regexp_instr</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type>
-         <optional>, <parameter>start</parameter> <type>integer</type>
-         <optional>, <parameter>N</parameter> <type>integer</type>
-         <optional>, <parameter>endoption</parameter> <type>integer</type>
-         <optional>, <parameter>flags</parameter> <type>text</type>
-         <optional>, <parameter>subexpr</parameter> <type>integer</type> </optional> </optional> </optional> </optional> </optional> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the position within <parameter>string</parameter> where
-        the <parameter>N</parameter>'th match of the POSIX regular
-        expression <parameter>pattern</parameter> occurs, or zero if there is
-        no such match; see <xref linkend="functions-posix-regexp"/>.
-       </para>
-       <para>
-        <literal>regexp_instr('ABCDEF', 'c(.)(..)', 1, 1, 0, 'i')</literal>
-        <returnvalue>3</returnvalue>
-       </para>
-       <para>
-        <literal>regexp_instr('ABCDEF', 'c(.)(..)', 1, 1, 0, 'i', 2)</literal>
-        <returnvalue>5</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regexp_like</primary>
-        </indexterm>
-        <function>regexp_like</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type>
-         <optional>, <parameter>flags</parameter> <type>text</type> </optional> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Checks whether a match of the POSIX regular
-        expression <parameter>pattern</parameter> occurs
-        within <parameter>string</parameter>; see
-        <xref linkend="functions-posix-regexp"/>.
-       </para>
-       <para>
-        <literal>regexp_like('Hello World', 'world$', 'i')</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regexp_match</primary>
-        </indexterm>
-        <function>regexp_match</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type> <optional>, <parameter>flags</parameter> <type>text</type> </optional> )
-        <returnvalue>text[]</returnvalue>
-       </para>
-       <para>
-        Returns substrings within the first match of the POSIX regular
-        expression <parameter>pattern</parameter> to
-        the <parameter>string</parameter>; see
-        <xref linkend="functions-posix-regexp"/>.
-       </para>
-       <para>
-        <literal>regexp_match('foobarbequebaz', '(bar)(beque)')</literal>
-        <returnvalue>{bar,beque}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regexp_matches</primary>
-        </indexterm>
-        <function>regexp_matches</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type> <optional>, <parameter>flags</parameter> <type>text</type> </optional> )
-        <returnvalue>setof text[]</returnvalue>
-       </para>
-       <para>
-        Returns substrings within the first match of the POSIX regular
-        expression <parameter>pattern</parameter> to
-        the <parameter>string</parameter>, or substrings within all
-        such matches if the <literal>g</literal> flag is used;
-        see <xref linkend="functions-posix-regexp"/>.
-       </para>
-       <para>
-        <literal>regexp_matches('foobarbequebaz', 'ba.', 'g')</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- {bar}
- {baz}
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regexp_replace</primary>
-        </indexterm>
-        <function>regexp_replace</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type>, <parameter>replacement</parameter> <type>text</type>
-         <optional>, <parameter>flags</parameter> <type>text</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Replaces the substring that is the first match to the POSIX
-        regular expression <parameter>pattern</parameter>, or all such
-        matches if the <literal>g</literal> flag is used; see
-        <xref linkend="functions-posix-regexp"/>.
-       </para>
-       <para>
-        <literal>regexp_replace('Thomas', '.[mN]a.', 'M')</literal>
-        <returnvalue>ThM</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>regexp_replace</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type>, <parameter>replacement</parameter> <type>text</type>,
-         <parameter>start</parameter> <type>integer</type>
-         <optional>, <parameter>N</parameter> <type>integer</type>
-         <optional>, <parameter>flags</parameter> <type>text</type> </optional> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Replaces the substring that is the <parameter>N</parameter>'th
-        match to the POSIX regular expression <parameter>pattern</parameter>,
-        or all such matches if <parameter>N</parameter> is zero, with the
-        search beginning at the <parameter>start</parameter>'th character
-        of <parameter>string</parameter>.  If <parameter>N</parameter> is
-        omitted, it defaults to 1.  See
-        <xref linkend="functions-posix-regexp"/>.
-       </para>
-       <para>
-        <literal>regexp_replace('Thomas', '.', 'X', 3, 2)</literal>
-        <returnvalue>ThoXas</returnvalue>
-       </para>
-       <para>
-        <literal>regexp_replace(string=>'hello world', pattern=>'l', replacement=>'XX', start=>1, "N"=>2)</literal>
-        <returnvalue>helXXo world</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regexp_split_to_array</primary>
-        </indexterm>
-        <function>regexp_split_to_array</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type> <optional>, <parameter>flags</parameter> <type>text</type> </optional> )
-        <returnvalue>text[]</returnvalue>
-       </para>
-       <para>
-        Splits <parameter>string</parameter> using a POSIX regular
-        expression as the delimiter, producing an array of results; see
-        <xref linkend="functions-posix-regexp"/>.
-       </para>
-       <para>
-        <literal>regexp_split_to_array('hello world', '\s+')</literal>
-        <returnvalue>{hello,world}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regexp_split_to_table</primary>
-        </indexterm>
-        <function>regexp_split_to_table</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type> <optional>, <parameter>flags</parameter> <type>text</type> </optional> )
-        <returnvalue>setof text</returnvalue>
-       </para>
-       <para>
-        Splits <parameter>string</parameter> using a POSIX regular
-        expression as the delimiter, producing a set of results; see
-        <xref linkend="functions-posix-regexp"/>.
-       </para>
-       <para>
-        <literal>regexp_split_to_table('hello world', '\s+')</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- hello
- world
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regexp_substr</primary>
-        </indexterm>
-        <function>regexp_substr</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type>
-         <optional>, <parameter>start</parameter> <type>integer</type>
-         <optional>, <parameter>N</parameter> <type>integer</type>
-         <optional>, <parameter>flags</parameter> <type>text</type>
-         <optional>, <parameter>subexpr</parameter> <type>integer</type> </optional> </optional> </optional> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the substring within <parameter>string</parameter> that
-        matches the <parameter>N</parameter>'th occurrence of the POSIX
-        regular expression <parameter>pattern</parameter>,
-        or <literal>NULL</literal> if there is no such match; see
-        <xref linkend="functions-posix-regexp"/>.
-       </para>
-       <para>
-        <literal>regexp_substr('ABCDEF', 'c(.)(..)', 1, 1, 'i')</literal>
-        <returnvalue>CDEF</returnvalue>
-       </para>
-       <para>
-        <literal>regexp_substr('ABCDEF', 'c(.)(..)', 1, 1, 'i', 2)</literal>
-        <returnvalue>EF</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>repeat</primary>
-        </indexterm>
-        <function>repeat</function> ( <parameter>string</parameter> <type>text</type>, <parameter>number</parameter> <type>integer</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Repeats <parameter>string</parameter> the specified
-        <parameter>number</parameter> of times.
-       </para>
-       <para>
-        <literal>repeat('Pg', 4)</literal>
-        <returnvalue>PgPgPgPg</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>replace</primary>
-        </indexterm>
-        <function>replace</function> ( <parameter>string</parameter> <type>text</type>,
-        <parameter>from</parameter> <type>text</type>,
-        <parameter>to</parameter> <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Replaces all occurrences in <parameter>string</parameter> of
-        substring <parameter>from</parameter> with
-        substring <parameter>to</parameter>.
-       </para>
-       <para>
-        <literal>replace('abcdefabcdef', 'cd', 'XX')</literal>
-        <returnvalue>abXXefabXXef</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>reverse</primary>
-        </indexterm>
-        <function>reverse</function> ( <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Reverses the order of the characters in the string.
-       </para>
-       <para>
-        <literal>reverse('abcde')</literal>
-        <returnvalue>edcba</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>right</primary>
-        </indexterm>
-        <function>right</function> ( <parameter>string</parameter> <type>text</type>,
-         <parameter>n</parameter> <type>integer</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns last <parameter>n</parameter> characters in the string,
-        or when <parameter>n</parameter> is negative, returns all but
-        first |<parameter>n</parameter>| characters.
-       </para>
-       <para>
-        <literal>right('abcde', 2)</literal>
-        <returnvalue>de</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>split_part</primary>
-        </indexterm>
-        <function>split_part</function> ( <parameter>string</parameter> <type>text</type>,
-        <parameter>delimiter</parameter> <type>text</type>,
-        <parameter>n</parameter> <type>integer</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Splits <parameter>string</parameter> at occurrences
-        of <parameter>delimiter</parameter> and returns
-        the <parameter>n</parameter>'th field (counting from one),
-        or when <parameter>n</parameter> is negative, returns
-        the |<parameter>n</parameter>|'th-from-last field.
-       </para>
-       <para>
-        <literal>split_part('abc~@~def~@~ghi', '~@~', 2)</literal>
-        <returnvalue>def</returnvalue>
-       </para>
-       <para>
-        <literal>split_part('abc,def,ghi,jkl', ',', -2)</literal>
-        <returnvalue>ghi</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>starts_with</primary>
-        </indexterm>
-        <function>starts_with</function> ( <parameter>string</parameter> <type>text</type>, <parameter>prefix</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Returns true if <parameter>string</parameter> starts
-        with <parameter>prefix</parameter>.
-       </para>
-       <para>
-        <literal>starts_with('alphabet', 'alph')</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm id="function-string-to-array">
-         <primary>string_to_array</primary>
-        </indexterm>
-        <function>string_to_array</function> ( <parameter>string</parameter> <type>text</type>, <parameter>delimiter</parameter> <type>text</type> <optional>, <parameter>null_string</parameter> <type>text</type> </optional> )
-        <returnvalue>text[]</returnvalue>
-       </para>
-       <para>
-        Splits the <parameter>string</parameter> at occurrences
-        of <parameter>delimiter</parameter> and forms the resulting fields
-        into a <type>text</type> array.
-        If <parameter>delimiter</parameter> is <literal>NULL</literal>,
-        each character in the <parameter>string</parameter> will become a
-        separate element in the array.
-        If <parameter>delimiter</parameter> is an empty string, then
-        the <parameter>string</parameter> is treated as a single field.
-        If <parameter>null_string</parameter> is supplied and is
-        not <literal>NULL</literal>, fields matching that string are
-        replaced by <literal>NULL</literal>.
-        See also <link linkend="function-array-to-string"><function>array_to_string</function></link>.
-       </para>
-       <para>
-        <literal>string_to_array('xx~~yy~~zz', '~~', 'yy')</literal>
-        <returnvalue>{xx,NULL,zz}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>string_to_table</primary>
-        </indexterm>
-        <function>string_to_table</function> ( <parameter>string</parameter> <type>text</type>, <parameter>delimiter</parameter> <type>text</type> <optional>, <parameter>null_string</parameter> <type>text</type> </optional> )
-        <returnvalue>setof text</returnvalue>
-       </para>
-       <para>
-        Splits the <parameter>string</parameter> at occurrences
-        of <parameter>delimiter</parameter> and returns the resulting fields
-        as a set of <type>text</type> rows.
-        If <parameter>delimiter</parameter> is <literal>NULL</literal>,
-        each character in the <parameter>string</parameter> will become a
-        separate row of the result.
-        If <parameter>delimiter</parameter> is an empty string, then
-        the <parameter>string</parameter> is treated as a single field.
-        If <parameter>null_string</parameter> is supplied and is
-        not <literal>NULL</literal>, fields matching that string are
-        replaced by <literal>NULL</literal>.
-       </para>
-       <para>
-        <literal>string_to_table('xx~^~yy~^~zz', '~^~', 'yy')</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- xx
- NULL
- zz
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>strpos</primary>
-        </indexterm>
-        <function>strpos</function> ( <parameter>string</parameter> <type>text</type>, <parameter>substring</parameter> <type>text</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns first starting index of the specified <parameter>substring</parameter>
-        within <parameter>string</parameter>, or zero if it's not present.
-        (Same as <literal>position(<parameter>substring</parameter> in
-        <parameter>string</parameter>)</literal>, but note the reversed
-        argument order.)
-       </para>
-       <para>
-        <literal>strpos('high', 'ig')</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>substr</primary>
-        </indexterm>
-        <function>substr</function> ( <parameter>string</parameter> <type>text</type>, <parameter>start</parameter> <type>integer</type> <optional>, <parameter>count</parameter> <type>integer</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Extracts the substring of <parameter>string</parameter> starting at
-        the <parameter>start</parameter>'th character,
-        and extending for <parameter>count</parameter> characters if that is
-        specified.  (Same
-        as <literal>substring(<parameter>string</parameter>
-        from <parameter>start</parameter>
-        for <parameter>count</parameter>)</literal>.)
-       </para>
-       <para>
-        <literal>substr('alphabet', 3)</literal>
-        <returnvalue>phabet</returnvalue>
-       </para>
-       <para>
-        <literal>substr('alphabet', 3, 2)</literal>
-        <returnvalue>ph</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_ascii</primary>
-        </indexterm>
-        <function>to_ascii</function> ( <parameter>string</parameter> <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>to_ascii</function> ( <parameter>string</parameter> <type>text</type>,
-        <parameter>encoding</parameter> <type>name</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>to_ascii</function> ( <parameter>string</parameter> <type>text</type>,
-        <parameter>encoding</parameter> <type>integer</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts <parameter>string</parameter> to <acronym>ASCII</acronym>
-        from another encoding, which may be identified by name or number.
-        If <parameter>encoding</parameter> is omitted the database encoding
-        is assumed (which in practice is the only useful case).
-        The conversion consists primarily of dropping accents.
-        Conversion is only supported
-        from <literal>LATIN1</literal>, <literal>LATIN2</literal>,
-        <literal>LATIN9</literal>, and <literal>WIN1250</literal> encodings.
-        (See the <xref linkend="unaccent"/> module for another, more flexible
-        solution.)
-       </para>
-       <para>
-        <literal>to_ascii('Kar&eacute;l')</literal>
-        <returnvalue>Karel</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_bin</primary>
-        </indexterm>
-        <function>to_bin</function> ( <type>integer</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>to_bin</function> ( <type>bigint</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts the number to its equivalent two's complement binary
-        representation.
-       </para>
-       <para>
-        <literal>to_bin(2147483647)</literal>
-        <returnvalue>1111111111111111111111111111111</returnvalue>
-       </para>
-       <para>
-        <literal>to_bin(-1234)</literal>
-        <returnvalue>11111111111111111111101100101110</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_hex</primary>
-        </indexterm>
-        <function>to_hex</function> ( <type>integer</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>to_hex</function> ( <type>bigint</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts the number to its equivalent two's complement hexadecimal
-        representation.
-       </para>
-       <para>
-        <literal>to_hex(2147483647)</literal>
-        <returnvalue>7fffffff</returnvalue>
-       </para>
-       <para>
-        <literal>to_hex(-1234)</literal>
-        <returnvalue>fffffb2e</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_oct</primary>
-        </indexterm>
-        <function>to_oct</function> ( <type>integer</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>to_oct</function> ( <type>bigint</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts the number to its equivalent two's complement octal
-        representation.
-       </para>
-       <para>
-        <literal>to_oct(2147483647)</literal>
-        <returnvalue>17777777777</returnvalue>
-       </para>
-       <para>
-        <literal>to_oct(-1234)</literal>
-        <returnvalue>37777775456</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>translate</primary>
-        </indexterm>
-        <function>translate</function> ( <parameter>string</parameter> <type>text</type>,
-        <parameter>from</parameter> <type>text</type>,
-        <parameter>to</parameter> <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Replaces each character in <parameter>string</parameter> that
-        matches a character in the <parameter>from</parameter> set with the
-        corresponding character in the <parameter>to</parameter>
-        set. If <parameter>from</parameter> is longer than
-        <parameter>to</parameter>, occurrences of the extra characters in
-        <parameter>from</parameter> are deleted.
-       </para>
-       <para>
-        <literal>translate('12345', '143', 'ax')</literal>
-        <returnvalue>a2x5</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>unistr</primary>
-        </indexterm>
-        <function>unistr</function> ( <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Evaluate escaped Unicode characters in the argument.  Unicode characters
-        can be specified as
-        <literal>\<replaceable>XXXX</replaceable></literal> (4 hexadecimal
-        digits), <literal>\+<replaceable>XXXXXX</replaceable></literal> (6
-        hexadecimal digits),
-        <literal>\u<replaceable>XXXX</replaceable></literal> (4 hexadecimal
-        digits), or <literal>\U<replaceable>XXXXXXXX</replaceable></literal>
-        (8 hexadecimal digits).  To specify a backslash, write two
-        backslashes.  All other characters are taken literally.
-       </para>
-
-       <para>
-        If the server encoding is not UTF-8, the Unicode code point identified
-        by one of these escape sequences is converted to the actual server
-        encoding; an error is reported if that's not possible.
-       </para>
-
-       <para>
-        This function provides a (non-standard) alternative to string
-        constants with Unicode escapes (see <xref
-        linkend="sql-syntax-strings-uescape"/>).
-       </para>
-
-       <para>
-        <literal>unistr('d\0061t\+000061')</literal>
-        <returnvalue>data</returnvalue>
-       </para>
-       <para>
-        <literal>unistr('d\u0061t\U00000061')</literal>
-        <returnvalue>data</returnvalue>
-       </para></entry>
-      </row>
-
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    The <function>concat</function>, <function>concat_ws</function> and
-    <function>format</function> functions are variadic, so it is possible to
-    pass the values to be concatenated or formatted as an array marked with
-    the <literal>VARIADIC</literal> keyword (see <xref
-    linkend="xfunc-sql-variadic-functions"/>).  The array's elements are
-    treated as if they were separate ordinary arguments to the function.
-    If the variadic array argument is NULL, <function>concat</function>
-    and <function>concat_ws</function> return NULL, but
-    <function>format</function> treats a NULL as a zero-element array.
-   </para>
-
-   <para>
-    See also the aggregate function <function>string_agg</function> in
-    <xref linkend="functions-aggregate"/>, and the functions for
-    converting between strings and the <type>bytea</type> type in
-    <xref linkend="functions-binarystring-conversions"/>.
-   </para>
-
-   <sect2 id="functions-string-format">
-    <title><function>format</function></title>
-
-    <indexterm>
-     <primary>format</primary>
-    </indexterm>
-
-    <para>
-     The function <function>format</function> produces output formatted according to
-     a format string, in a style similar to the C function
-     <function>sprintf</function>.
-    </para>
-
-    <para>
-<synopsis>
-<function>format</function>(<parameter>formatstr</parameter> <type>text</type> <optional>, <parameter>formatarg</parameter> <type>"any"</type> <optional>, ...</optional> </optional>)
-</synopsis>
-     <parameter>formatstr</parameter> is a format string that specifies how the
-     result should be formatted.  Text in the format string is copied
-     directly to the result, except where <firstterm>format specifiers</firstterm> are
-     used.  Format specifiers act as placeholders in the string, defining how
-     subsequent function arguments should be formatted and inserted into the
-     result.  Each <parameter>formatarg</parameter> argument is converted to text
-     according to the usual output rules for its data type, and then formatted
-     and inserted into the result string according to the format specifier(s).
-    </para>
-
-    <para>
-     Format specifiers are introduced by a <literal>%</literal> character and have
-     the form
-<synopsis>
-%[<parameter>position</parameter>][<parameter>flags</parameter>][<parameter>width</parameter>]<parameter>type</parameter>
-</synopsis>
-     where the component fields are:
-
-     <variablelist>
-      <varlistentry>
-       <term><parameter>position</parameter> (optional)</term>
-       <listitem>
-        <para>
-         A string of the form <literal><parameter>n</parameter>$</literal> where
-         <parameter>n</parameter> is the index of the argument to print.
-         Index 1 means the first argument after
-         <parameter>formatstr</parameter>.  If the <parameter>position</parameter> is
-         omitted, the default is to use the next argument in sequence.
-        </para>
-       </listitem>
-      </varlistentry>
-
-      <varlistentry>
-       <term><parameter>flags</parameter> (optional)</term>
-       <listitem>
-        <para>
-         Additional options controlling how the format specifier's output is
-         formatted.  Currently the only supported flag is a minus sign
-         (<literal>-</literal>) which will cause the format specifier's output to be
-         left-justified.  This has no effect unless the <parameter>width</parameter>
-         field is also specified.
-        </para>
-       </listitem>
-      </varlistentry>
-
-      <varlistentry>
-       <term><parameter>width</parameter> (optional)</term>
-       <listitem>
-        <para>
-         Specifies the <emphasis>minimum</emphasis> number of characters to use to
-         display the format specifier's output.  The output is padded on the
-         left or right (depending on the <literal>-</literal> flag) with spaces as
-         needed to fill the width.  A too-small width does not cause
-         truncation of the output, but is simply ignored.  The width may be
-         specified using any of the following: a positive integer; an
-         asterisk (<literal>*</literal>) to use the next function argument as the
-         width; or a string of the form <literal>*<parameter>n</parameter>$</literal> to
-         use the <parameter>n</parameter>th function argument as the width.
-        </para>
-
-        <para>
-         If the width comes from a function argument, that argument is
-         consumed before the argument that is used for the format specifier's
-         value.  If the width argument is negative, the result is left
-         aligned (as if the <literal>-</literal> flag had been specified) within a
-         field of length <function>abs</function>(<parameter>width</parameter>).
-        </para>
-       </listitem>
-      </varlistentry>
-
-      <varlistentry>
-       <term><parameter>type</parameter> (required)</term>
-       <listitem>
-        <para>
-         The type of format conversion to use to produce the format
-         specifier's output.  The following types are supported:
-         <itemizedlist>
-          <listitem>
-           <para>
-            <literal>s</literal> formats the argument value as a simple
-            string.  A null value is treated as an empty string.
-           </para>
-          </listitem>
-          <listitem>
-           <para>
-            <literal>I</literal> treats the argument value as an SQL
-            identifier, double-quoting it if necessary.
-            It is an error for the value to be null (equivalent to
-            <function>quote_ident</function>).
-           </para>
-          </listitem>
-          <listitem>
-           <para>
-            <literal>L</literal> quotes the argument value as an SQL literal.
-            A null value is displayed as the string <literal>NULL</literal>, without
-            quotes (equivalent to <function>quote_nullable</function>).
-           </para>
-          </listitem>
-         </itemizedlist>
-        </para>
-       </listitem>
-      </varlistentry>
-     </variablelist>
-    </para>
-
-    <para>
-     In addition to the format specifiers described above, the special sequence
-     <literal>%%</literal> may be used to output a literal <literal>%</literal> character.
-    </para>
-
-    <para>
-     Here are some examples of the basic format conversions:
-
-<screen>
-SELECT format('Hello %s', 'World');
-<lineannotation>Result: </lineannotation><computeroutput>Hello World</computeroutput>
-
-SELECT format('Testing %s, %s, %s, %%', 'one', 'two', 'three');
-<lineannotation>Result: </lineannotation><computeroutput>Testing one, two, three, %</computeroutput>
-
-SELECT format('INSERT INTO %I VALUES(%L)', 'Foo bar', E'O\'Reilly');
-<lineannotation>Result: </lineannotation><computeroutput>INSERT INTO "Foo bar" VALUES('O''Reilly')</computeroutput>
-
-SELECT format('INSERT INTO %I VALUES(%L)', 'locations', 'C:\Program Files');
-<lineannotation>Result: </lineannotation><computeroutput>INSERT INTO locations VALUES('C:\Program Files')</computeroutput>
-</screen>
-    </para>
-
-    <para>
-     Here are examples using <parameter>width</parameter> fields
-     and the <literal>-</literal> flag:
-
-<screen>
-SELECT format('|%10s|', 'foo');
-<lineannotation>Result: </lineannotation><computeroutput>|       foo|</computeroutput>
-
-SELECT format('|%-10s|', 'foo');
-<lineannotation>Result: </lineannotation><computeroutput>|foo       |</computeroutput>
-
-SELECT format('|%*s|', 10, 'foo');
-<lineannotation>Result: </lineannotation><computeroutput>|       foo|</computeroutput>
-
-SELECT format('|%*s|', -10, 'foo');
-<lineannotation>Result: </lineannotation><computeroutput>|foo       |</computeroutput>
-
-SELECT format('|%-*s|', 10, 'foo');
-<lineannotation>Result: </lineannotation><computeroutput>|foo       |</computeroutput>
-
-SELECT format('|%-*s|', -10, 'foo');
-<lineannotation>Result: </lineannotation><computeroutput>|foo       |</computeroutput>
-</screen>
-    </para>
-
-    <para>
-     These examples show use of <parameter>position</parameter> fields:
-
-<screen>
-SELECT format('Testing %3$s, %2$s, %1$s', 'one', 'two', 'three');
-<lineannotation>Result: </lineannotation><computeroutput>Testing three, two, one</computeroutput>
-
-SELECT format('|%*2$s|', 'foo', 10, 'bar');
-<lineannotation>Result: </lineannotation><computeroutput>|       bar|</computeroutput>
-
-SELECT format('|%1$*2$s|', 'foo', 10, 'bar');
-<lineannotation>Result: </lineannotation><computeroutput>|       foo|</computeroutput>
-</screen>
-    </para>
-
-    <para>
-     Unlike the standard C function <function>sprintf</function>,
-     <productname>PostgreSQL</productname>'s <function>format</function> function allows format
-     specifiers with and without <parameter>position</parameter> fields to be mixed
-     in the same format string.  A format specifier without a
-     <parameter>position</parameter> field always uses the next argument after the
-     last argument consumed.
-     In addition, the <function>format</function> function does not require all
-     function arguments to be used in the format string.
-     For example:
-
-<screen>
-SELECT format('Testing %3$s, %2$s, %s', 'one', 'two', 'three');
-<lineannotation>Result: </lineannotation><computeroutput>Testing three, two, three</computeroutput>
-</screen>
-    </para>
-
-    <para>
-     The <literal>%I</literal> and <literal>%L</literal> format specifiers are particularly
-     useful for safely constructing dynamic SQL statements.  See
-     <xref linkend="plpgsql-quote-literal-example"/>.
-    </para>
-   </sect2>
-
-  </sect1>
-
-
-  <sect1 id="functions-binarystring">
-   <title>Binary String Functions and Operators</title>
-
-   <indexterm zone="functions-binarystring">
-    <primary>binary data</primary>
-    <secondary>functions</secondary>
-   </indexterm>
-
-   <para>
-    This section describes functions and operators for examining and
-    manipulating binary strings, that is values of type <type>bytea</type>.
-    Many of these are equivalent, in purpose and syntax, to the
-    text-string functions described in the previous section.
-   </para>
-
-   <para>
-    <acronym>SQL</acronym> defines some string functions that use
-    key words, rather than commas, to separate
-    arguments.  Details are in
-    <xref linkend="functions-binarystring-sql"/>.
-    <productname>PostgreSQL</productname> also provides versions of these functions
-    that use the regular function invocation syntax
-    (see <xref linkend="functions-binarystring-other"/>).
-   </para>
-
-   <table id="functions-binarystring-sql">
-    <title><acronym>SQL</acronym> Binary String Functions and Operators</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function/Operator
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>binary string</primary>
-         <secondary>concatenation</secondary>
-        </indexterm>
-        <type>bytea</type> <literal>||</literal> <type>bytea</type>
-        <returnvalue>bytea</returnvalue>
-       </para>
-       <para>
-        Concatenates the two binary strings.
-       </para>
-       <para>
-        <literal>'\x123456'::bytea || '\x789a00bcde'::bytea</literal>
-        <returnvalue>\x123456789a00bcde</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>bit_length</primary>
-        </indexterm>
-        <function>bit_length</function> ( <type>bytea</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns number of bits in the binary string (8
-        times the <function>octet_length</function>).
-       </para>
-       <para>
-        <literal>bit_length('\x123456'::bytea)</literal>
-        <returnvalue>24</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>btrim</primary>
-        </indexterm>
-        <function>btrim</function> ( <parameter>bytes</parameter> <type>bytea</type>,
-        <parameter>bytesremoved</parameter> <type>bytea</type> )
-        <returnvalue>bytea</returnvalue>
-       </para>
-       <para>
-        Removes the longest string containing only bytes appearing in
-        <parameter>bytesremoved</parameter> from the start and end of
-        <parameter>bytes</parameter>.
-       </para>
-       <para>
-        <literal>btrim('\x1234567890'::bytea, '\x9012'::bytea)</literal>
-        <returnvalue>\x345678</returnvalue>
-       </para></entry>
-      </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>ltrim</primary>
-         </indexterm>
-         <function>ltrim</function> ( <parameter>bytes</parameter> <type>bytea</type>,
-         <parameter>bytesremoved</parameter> <type>bytea</type> )
-         <returnvalue>bytea</returnvalue>
-        </para>
-        <para>
-         Removes the longest string containing only bytes appearing in
-         <parameter>bytesremoved</parameter> from the start of
-         <parameter>bytes</parameter>.
-        </para>
-        <para>
-         <literal>ltrim('\x1234567890'::bytea, '\x9012'::bytea)</literal>
-         <returnvalue>\x34567890</returnvalue>
-        </para></entry>
-       </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>octet_length</primary>
-        </indexterm>
-        <function>octet_length</function> ( <type>bytea</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns number of bytes in the binary string.
-       </para>
-       <para>
-        <literal>octet_length('\x123456'::bytea)</literal>
-        <returnvalue>3</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>overlay</primary>
-        </indexterm>
-        <function>overlay</function> ( <parameter>bytes</parameter> <type>bytea</type> <literal>PLACING</literal> <parameter>newsubstring</parameter> <type>bytea</type> <literal>FROM</literal> <parameter>start</parameter> <type>integer</type> <optional> <literal>FOR</literal> <parameter>count</parameter> <type>integer</type> </optional> )
-        <returnvalue>bytea</returnvalue>
-       </para>
-       <para>
-        Replaces the substring of <parameter>bytes</parameter> that starts at
-        the <parameter>start</parameter>'th byte and extends
-        for <parameter>count</parameter> bytes
-        with <parameter>newsubstring</parameter>.
-        If <parameter>count</parameter> is omitted, it defaults to the length
-        of <parameter>newsubstring</parameter>.
-       </para>
-       <para>
-        <literal>overlay('\x1234567890'::bytea placing '\002\003'::bytea from 2 for 3)</literal>
-        <returnvalue>\x12020390</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>position</primary>
-        </indexterm>
-        <function>position</function> ( <parameter>substring</parameter> <type>bytea</type> <literal>IN</literal> <parameter>bytes</parameter> <type>bytea</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns first starting index of the specified
-        <parameter>substring</parameter> within
-        <parameter>bytes</parameter>, or zero if it's not present.
-       </para>
-       <para>
-        <literal>position('\x5678'::bytea in '\x1234567890'::bytea)</literal>
-        <returnvalue>3</returnvalue>
-       </para></entry>
-      </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>rtrim</primary>
-         </indexterm>
-         <function>rtrim</function> ( <parameter>bytes</parameter> <type>bytea</type>,
-         <parameter>bytesremoved</parameter> <type>bytea</type> )
-         <returnvalue>bytea</returnvalue>
-        </para>
-        <para>
-         Removes the longest string containing only bytes appearing in
-         <parameter>bytesremoved</parameter> from the end of
-         <parameter>bytes</parameter>.
-        </para>
-        <para>
-         <literal>rtrim('\x1234567890'::bytea, '\x9012'::bytea)</literal>
-         <returnvalue>\x12345678</returnvalue>
-        </para></entry>
-       </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>substring</primary>
-        </indexterm>
-        <function>substring</function> ( <parameter>bytes</parameter> <type>bytea</type> <optional> <literal>FROM</literal> <parameter>start</parameter> <type>integer</type> </optional> <optional> <literal>FOR</literal> <parameter>count</parameter> <type>integer</type> </optional> )
-        <returnvalue>bytea</returnvalue>
-       </para>
-       <para>
-        Extracts the substring of <parameter>bytes</parameter> starting at
-        the <parameter>start</parameter>'th byte if that is specified,
-        and stopping after <parameter>count</parameter> bytes if that is
-        specified.  Provide at least one of <parameter>start</parameter>
-        and <parameter>count</parameter>.
-       </para>
-       <para>
-        <literal>substring('\x1234567890'::bytea from 3 for 2)</literal>
-        <returnvalue>\x5678</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>trim</primary>
-        </indexterm>
-        <function>trim</function> ( <optional> <literal>LEADING</literal> | <literal>TRAILING</literal> | <literal>BOTH</literal> </optional>
-        <parameter>bytesremoved</parameter> <type>bytea</type> <literal>FROM</literal>
-        <parameter>bytes</parameter> <type>bytea</type> )
-        <returnvalue>bytea</returnvalue>
-       </para>
-       <para>
-        Removes the longest string containing only bytes appearing in
-        <parameter>bytesremoved</parameter> from the start,
-        end, or both ends (<literal>BOTH</literal> is the default)
-        of <parameter>bytes</parameter>.
-       </para>
-       <para>
-        <literal>trim('\x9012'::bytea from '\x1234567890'::bytea)</literal>
-        <returnvalue>\x345678</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>trim</function> ( <optional> <literal>LEADING</literal> | <literal>TRAILING</literal> | <literal>BOTH</literal> </optional> <optional> <literal>FROM</literal> </optional>
-        <parameter>bytes</parameter> <type>bytea</type>,
-        <parameter>bytesremoved</parameter> <type>bytea</type> )
-        <returnvalue>bytea</returnvalue>
-       </para>
-       <para>
-        This is a non-standard syntax for <function>trim()</function>.
-       </para>
-       <para>
-        <literal>trim(both from '\x1234567890'::bytea, '\x9012'::bytea)</literal>
-        <returnvalue>\x345678</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    Additional binary string manipulation functions are available and
-    are listed in <xref linkend="functions-binarystring-other"/>.  Some
-    of them are used internally to implement the
-    <acronym>SQL</acronym>-standard string functions listed in <xref
-    linkend="functions-binarystring-sql"/>.
-   </para>
-
-   <table id="functions-binarystring-other">
-    <title>Other Binary String Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>bit_count</primary>
-        </indexterm>
-        <indexterm>
-         <primary>popcount</primary>
-         <see>bit_count</see>
-        </indexterm>
-        <function>bit_count</function> ( <parameter>bytes</parameter> <type>bytea</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Returns the number of bits set in the binary string (also known as
-        <quote>popcount</quote>).
-       </para>
-       <para>
-        <literal>bit_count('\x1234567890'::bytea)</literal>
-        <returnvalue>15</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>crc32</primary>
-        </indexterm>
-        <function>crc32</function> ( <type>bytea</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Computes the CRC-32 value of the binary string.
-       </para>
-       <para>
-        <literal>crc32('abc'::bytea)</literal>
-        <returnvalue>891568578</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>crc32c</primary>
-        </indexterm>
-        <function>crc32c</function> ( <type>bytea</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Computes the CRC-32C value of the binary string.
-       </para>
-       <para>
-        <literal>crc32c('abc'::bytea)</literal>
-        <returnvalue>910901175</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>get_bit</primary>
-        </indexterm>
-        <function>get_bit</function> ( <parameter>bytes</parameter> <type>bytea</type>,
-        <parameter>n</parameter> <type>bigint</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Extracts <link linkend="functions-zerobased-note">n'th</link> bit
-        from binary string.
-       </para>
-       <para>
-        <literal>get_bit('\x1234567890'::bytea, 30)</literal>
-        <returnvalue>1</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>get_byte</primary>
-        </indexterm>
-        <function>get_byte</function> ( <parameter>bytes</parameter> <type>bytea</type>,
-        <parameter>n</parameter> <type>integer</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Extracts <link linkend="functions-zerobased-note">n'th</link> byte
-        from binary string.
-       </para>
-       <para>
-        <literal>get_byte('\x1234567890'::bytea, 4)</literal>
-        <returnvalue>144</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>length</primary>
-        </indexterm>
-        <indexterm>
-         <primary>binary string</primary>
-         <secondary>length</secondary>
-        </indexterm>
-        <indexterm>
-         <primary>length</primary>
-         <secondary sortas="binary string">of a binary string</secondary>
-         <see>binary strings, length</see>
-        </indexterm>
-        <function>length</function> ( <type>bytea</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the number of bytes in the binary string.
-       </para>
-       <para>
-        <literal>length('\x1234567890'::bytea)</literal>
-        <returnvalue>5</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>length</function> ( <parameter>bytes</parameter> <type>bytea</type>,
-        <parameter>encoding</parameter> <type>name</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the number of characters in the binary string, assuming
-        that it is text in the given <parameter>encoding</parameter>.
-       </para>
-       <para>
-        <literal>length('jose'::bytea, 'UTF8')</literal>
-        <returnvalue>4</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>md5</primary>
-        </indexterm>
-        <function>md5</function> ( <type>bytea</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Computes the MD5 <link linkend="functions-hash-note">hash</link> of
-        the binary string, with the result written in hexadecimal.
-       </para>
-       <para>
-        <literal>md5('Th\000omas'::bytea)</literal>
-        <returnvalue>8ab2d3c9689aaf18&zwsp;b4958c334c82d8b1</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>reverse</primary>
-        </indexterm>
-        <function>reverse</function> ( <type>bytea</type> )
-        <returnvalue>bytea</returnvalue>
-       </para>
-       <para>
-        Reverses the order of the bytes in the binary string.
-       </para>
-       <para>
-        <literal>reverse('\xabcd'::bytea)</literal>
-        <returnvalue>\xcdab</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>set_bit</primary>
-        </indexterm>
-        <function>set_bit</function> ( <parameter>bytes</parameter> <type>bytea</type>,
-        <parameter>n</parameter> <type>bigint</type>,
-        <parameter>newvalue</parameter> <type>integer</type> )
-        <returnvalue>bytea</returnvalue>
-       </para>
-       <para>
-        Sets <link linkend="functions-zerobased-note">n'th</link> bit in
-        binary string to <parameter>newvalue</parameter>.
-       </para>
-       <para>
-        <literal>set_bit('\x1234567890'::bytea, 30, 0)</literal>
-        <returnvalue>\x1234563890</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>set_byte</primary>
-        </indexterm>
-        <function>set_byte</function> ( <parameter>bytes</parameter> <type>bytea</type>,
-        <parameter>n</parameter> <type>integer</type>,
-        <parameter>newvalue</parameter> <type>integer</type> )
-        <returnvalue>bytea</returnvalue>
-       </para>
-       <para>
-        Sets <link linkend="functions-zerobased-note">n'th</link> byte in
-        binary string to <parameter>newvalue</parameter>.
-       </para>
-       <para>
-        <literal>set_byte('\x1234567890'::bytea, 4, 64)</literal>
-        <returnvalue>\x1234567840</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>sha224</primary>
-        </indexterm>
-        <function>sha224</function> ( <type>bytea</type> )
-        <returnvalue>bytea</returnvalue>
-       </para>
-       <para>
-        Computes the SHA-224 <link linkend="functions-hash-note">hash</link>
-        of the binary string.
-       </para>
-       <para>
-        <literal>sha224('abc'::bytea)</literal>
-        <returnvalue>\x23097d223405d8228642a477bda2&zwsp;55b32aadbce4bda0b3f7e36c9da7</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>sha256</primary>
-        </indexterm>
-        <function>sha256</function> ( <type>bytea</type> )
-        <returnvalue>bytea</returnvalue>
-       </para>
-       <para>
-        Computes the SHA-256 <link linkend="functions-hash-note">hash</link>
-        of the binary string.
-       </para>
-       <para>
-        <literal>sha256('abc'::bytea)</literal>
-        <returnvalue>\xba7816bf8f01cfea414140de5dae2223&zwsp;b00361a396177a9cb410ff61f20015ad</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>sha384</primary>
-        </indexterm>
-        <function>sha384</function> ( <type>bytea</type> )
-        <returnvalue>bytea</returnvalue>
-       </para>
-       <para>
-        Computes the SHA-384 <link linkend="functions-hash-note">hash</link>
-        of the binary string.
-       </para>
-       <para>
-        <literal>sha384('abc'::bytea)</literal>
-        <returnvalue>\xcb00753f45a35e8bb5a03d699ac65007&zwsp;272c32ab0eded1631a8b605a43ff5bed&zwsp;8086072ba1e7cc2358baeca134c825a7</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>sha512</primary>
-        </indexterm>
-        <function>sha512</function> ( <type>bytea</type> )
-        <returnvalue>bytea</returnvalue>
-       </para>
-       <para>
-        Computes the SHA-512 <link linkend="functions-hash-note">hash</link>
-        of the binary string.
-       </para>
-       <para>
-        <literal>sha512('abc'::bytea)</literal>
-        <returnvalue>\xddaf35a193617abacc417349ae204131&zwsp;12e6fa4e89a97ea20a9eeee64b55d39a&zwsp;2192992a274fc1a836ba3c23a3feebbd&zwsp;454d4423643ce80e2a9ac94fa54ca49f</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>substr</primary>
-        </indexterm>
-        <function>substr</function> ( <parameter>bytes</parameter> <type>bytea</type>, <parameter>start</parameter> <type>integer</type> <optional>, <parameter>count</parameter> <type>integer</type> </optional> )
-        <returnvalue>bytea</returnvalue>
-       </para>
-       <para>
-        Extracts the substring of <parameter>bytes</parameter> starting at
-        the <parameter>start</parameter>'th byte,
-        and extending for <parameter>count</parameter> bytes if that is
-        specified.  (Same
-        as <literal>substring(<parameter>bytes</parameter>
-        from <parameter>start</parameter>
-        for <parameter>count</parameter>)</literal>.)
-       </para>
-       <para>
-        <literal>substr('\x1234567890'::bytea, 3, 2)</literal>
-        <returnvalue>\x5678</returnvalue>
-       </para></entry>
-      </row>
-    </tbody>
-   </tgroup>
-  </table>
-
-  <para id="functions-zerobased-note">
-   Functions <function>get_byte</function> and <function>set_byte</function>
-   number the first byte of a binary string as byte 0.
-   Functions <function>get_bit</function> and <function>set_bit</function>
-   number bits from the right within each byte; for example bit 0 is the least
-   significant bit of the first byte, and bit 15 is the most significant bit
-   of the second byte.
-  </para>
-
-  <para id="functions-hash-note">
-   For historical reasons, the function <function>md5</function>
-   returns a hex-encoded value of type <type>text</type> whereas the SHA-2
-   functions return type <type>bytea</type>.  Use the functions
-   <link linkend="function-encode"><function>encode</function></link>
-   and <link linkend="function-decode"><function>decode</function></link> to
-   convert between the two.  For example write <literal>encode(sha256('abc'),
-   'hex')</literal> to get a hex-encoded text representation,
-   or <literal>decode(md5('abc'), 'hex')</literal> to get
-   a <type>bytea</type> value.
-  </para>
-
-  <para>
-   <indexterm>
-    <primary>character string</primary>
-    <secondary>converting to binary string</secondary>
-   </indexterm>
-   <indexterm>
-    <primary>binary string</primary>
-    <secondary>converting to character string</secondary>
-   </indexterm>
-   Functions for converting strings between different character sets
-   (encodings), and for representing arbitrary binary data in textual
-   form, are shown in
-   <xref linkend="functions-binarystring-conversions"/>.  For these
-   functions, an argument or result of type <type>text</type> is expressed
-   in the database's default encoding, while arguments or results of
-   type <type>bytea</type> are in an encoding named by another argument.
-  </para>
-
-  <table id="functions-binarystring-conversions">
-   <title>Text/Binary String Conversion Functions</title>
-   <tgroup cols="1">
-    <thead>
-     <row>
-      <entry role="func_table_entry"><para role="func_signature">
-       Function
-      </para>
-      <para>
-       Description
-      </para>
-      <para>
-       Example(s)
-      </para></entry>
-     </row>
-    </thead>
-
-    <tbody>
-     <row>
-      <entry role="func_table_entry"><para role="func_signature">
-       <indexterm>
-        <primary>convert</primary>
-       </indexterm>
-       <function>convert</function> ( <parameter>bytes</parameter> <type>bytea</type>,
-       <parameter>src_encoding</parameter> <type>name</type>,
-       <parameter>dest_encoding</parameter> <type>name</type> )
-       <returnvalue>bytea</returnvalue>
-      </para>
-      <para>
-       Converts a binary string representing text in
-       encoding <parameter>src_encoding</parameter>
-       to a binary string in encoding <parameter>dest_encoding</parameter>
-       (see <xref linkend="multibyte-conversions-supported"/> for
-       available conversions).
-      </para>
-      <para>
-       <literal>convert('text_in_utf8', 'UTF8', 'LATIN1')</literal>
-       <returnvalue>\x746578745f696e5f75746638</returnvalue>
-      </para></entry>
-     </row>
-
-     <row>
-      <entry role="func_table_entry"><para role="func_signature">
-       <indexterm>
-        <primary>convert_from</primary>
-       </indexterm>
-       <function>convert_from</function> ( <parameter>bytes</parameter> <type>bytea</type>,
-       <parameter>src_encoding</parameter> <type>name</type> )
-       <returnvalue>text</returnvalue>
-      </para>
-      <para>
-       Converts a binary string representing text in
-       encoding <parameter>src_encoding</parameter>
-       to <type>text</type> in the database encoding
-       (see <xref linkend="multibyte-conversions-supported"/> for
-       available conversions).
-      </para>
-      <para>
-       <literal>convert_from('text_in_utf8', 'UTF8')</literal>
-       <returnvalue>text_in_utf8</returnvalue>
-      </para></entry>
-     </row>
-
-     <row>
-      <entry role="func_table_entry"><para role="func_signature">
-       <indexterm>
-        <primary>convert_to</primary>
-       </indexterm>
-       <function>convert_to</function> ( <parameter>string</parameter> <type>text</type>,
-       <parameter>dest_encoding</parameter> <type>name</type> )
-       <returnvalue>bytea</returnvalue>
-      </para>
-      <para>
-       Converts a <type>text</type> string (in the database encoding) to a
-       binary string encoded in encoding <parameter>dest_encoding</parameter>
-       (see <xref linkend="multibyte-conversions-supported"/> for
-       available conversions).
-      </para>
-      <para>
-       <literal>convert_to('some_text', 'UTF8')</literal>
-       <returnvalue>\x736f6d655f74657874</returnvalue>
-      </para></entry>
-     </row>
-
-     <row>
-      <entry role="func_table_entry"><para role="func_signature">
-       <indexterm id="function-encode">
-        <primary>encode</primary>
-       </indexterm>
-       <function>encode</function> ( <parameter>bytes</parameter> <type>bytea</type>,
-       <parameter>format</parameter> <type>text</type> )
-       <returnvalue>text</returnvalue>
-      </para>
-      <para>
-       Encodes binary data into a textual representation; supported
-       <parameter>format</parameter> values are:
-       <link linkend="encode-format-base64"><literal>base64</literal></link>,
-       <link linkend="encode-format-escape"><literal>escape</literal></link>,
-       <link linkend="encode-format-hex"><literal>hex</literal></link>.
-      </para>
-      <para>
-       <literal>encode('123\000\001', 'base64')</literal>
-       <returnvalue>MTIzAAE=</returnvalue>
-      </para></entry>
-     </row>
-
-     <row>
-      <entry role="func_table_entry"><para role="func_signature">
-       <indexterm id="function-decode">
-        <primary>decode</primary>
-       </indexterm>
-       <function>decode</function> ( <parameter>string</parameter> <type>text</type>,
-       <parameter>format</parameter> <type>text</type> )
-       <returnvalue>bytea</returnvalue>
-      </para>
-      <para>
-       Decodes binary data from a textual representation; supported
-       <parameter>format</parameter> values are the same as
-       for <function>encode</function>.
-      </para>
-      <para>
-       <literal>decode('MTIzAAE=', 'base64')</literal>
-       <returnvalue>\x3132330001</returnvalue>
-      </para></entry>
-     </row>
-    </tbody>
-   </tgroup>
-  </table>
-
-  <para>
-   The <function>encode</function> and <function>decode</function>
-   functions support the following textual formats:
-
-   <variablelist>
-    <varlistentry id="encode-format-base64">
-     <term>base64
-     <indexterm>
-      <primary>base64 format</primary>
-     </indexterm></term>
-     <listitem>
-      <para>
-       The <literal>base64</literal> format is that
-       of <ulink url="https://datatracker.ietf.org/doc/html/rfc2045#section-6.8">RFC
-       2045 Section 6.8</ulink>.  As per the <acronym>RFC</acronym>, encoded lines are
-       broken at 76 characters.  However instead of the MIME CRLF
-       end-of-line marker, only a newline is used for end-of-line.
-       The <function>decode</function> function ignores carriage-return,
-       newline, space, and tab characters.  Otherwise, an error is
-       raised when <function>decode</function> is supplied invalid
-       base64 data &mdash; including when trailing padding is incorrect.
-      </para>
-     </listitem>
-    </varlistentry>
-
-    <varlistentry id="encode-format-escape">
-     <term>escape
-     <indexterm>
-      <primary>escape format</primary>
-     </indexterm></term>
-     <listitem>
-      <para>
-       The <literal>escape</literal> format converts zero bytes and
-       bytes with the high bit set into octal escape sequences
-       (<literal>\</literal><replaceable>nnn</replaceable>), and it doubles
-       backslashes.  Other byte values are represented literally.
-       The <function>decode</function> function will raise an error if a
-       backslash is not followed by either a second backslash or three
-       octal digits; it accepts other byte values unchanged.
-      </para>
-     </listitem>
-    </varlistentry>
-
-    <varlistentry id="encode-format-hex">
-     <term>hex
-     <indexterm>
-      <primary>hex format</primary>
-     </indexterm></term>
-     <listitem>
-      <para>
-       The <literal>hex</literal> format represents each 4 bits of
-       data as one hexadecimal digit, <literal>0</literal>
-       through <literal>f</literal>, writing the higher-order digit of
-       each byte first.  The <function>encode</function> function outputs
-       the <literal>a</literal>-<literal>f</literal> hex digits in lower
-       case.  Because the smallest unit of data is 8 bits, there are
-       always an even number of characters returned
-       by <function>encode</function>.
-       The <function>decode</function> function
-       accepts the <literal>a</literal>-<literal>f</literal> characters in
-       either upper or lower case.  An error is raised
-       when <function>decode</function> is given invalid hex data
-       &mdash; including when given an odd number of characters.
-      </para>
-     </listitem>
-    </varlistentry>
-   </variablelist>
-  </para>
-
-  <para>
-   In addition, it is possible to cast integral values to and from type
-   <type>bytea</type>. Casting an integer to <type>bytea</type> produces
-   2, 4, or 8 bytes, depending on the width of the integer type. The result
-   is the two's complement representation of the integer, with the most
-   significant byte first. Some examples:
-<programlisting>
-1234::smallint::bytea          <lineannotation>\x04d2</lineannotation>
-cast(1234 as bytea)            <lineannotation>\x000004d2</lineannotation>
-cast(-1234 as bytea)           <lineannotation>\xfffffb2e</lineannotation>
-'\x8000'::bytea::smallint      <lineannotation>-32768</lineannotation>
-'\x8000'::bytea::integer       <lineannotation>32768</lineannotation>
-</programlisting>
-   Casting a <type>bytea</type> to an integer will raise an error if the
-   length of the <type>bytea</type> exceeds the width of the integer type.
-  </para>
-
-  <para>
-   See also the aggregate function <function>string_agg</function> in
-   <xref linkend="functions-aggregate"/> and the large object functions
-   in <xref linkend="lo-funcs"/>.
-  </para>
- </sect1>
-
-
-  <sect1 id="functions-bitstring">
-   <title>Bit String Functions and Operators</title>
-
-   <indexterm zone="functions-bitstring">
-    <primary>bit strings</primary>
-    <secondary>functions</secondary>
-   </indexterm>
-
-   <para>
-    This section describes functions and operators for examining and
-    manipulating bit strings, that is values of the types
-    <type>bit</type> and <type>bit varying</type>.  (While only
-    type <type>bit</type> is mentioned in these tables, values of
-    type <type>bit varying</type> can be used interchangeably.)
-    Bit strings support the usual comparison operators shown in
-    <xref linkend="functions-comparison-op-table"/>, as well as the
-    operators shown in <xref linkend="functions-bit-string-op-table"/>.
-   </para>
-
-   <table id="functions-bit-string-op-table">
-    <title>Bit String Operators</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Operator
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>bit</type> <literal>||</literal> <type>bit</type>
-        <returnvalue>bit</returnvalue>
-       </para>
-       <para>
-        Concatenation
-       </para>
-       <para>
-        <literal>B'10001' || B'011'</literal>
-        <returnvalue>10001011</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>bit</type> <literal>&amp;</literal> <type>bit</type>
-        <returnvalue>bit</returnvalue>
-       </para>
-       <para>
-        Bitwise AND (inputs must be of equal length)
-       </para>
-       <para>
-        <literal>B'10001' &amp; B'01101'</literal>
-        <returnvalue>00001</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>bit</type> <literal>|</literal> <type>bit</type>
-        <returnvalue>bit</returnvalue>
-       </para>
-       <para>
-        Bitwise OR (inputs must be of equal length)
-       </para>
-       <para>
-        <literal>B'10001' | B'01101'</literal>
-        <returnvalue>11101</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>bit</type> <literal>#</literal> <type>bit</type>
-        <returnvalue>bit</returnvalue>
-       </para>
-       <para>
-        Bitwise exclusive OR (inputs must be of equal length)
-       </para>
-       <para>
-        <literal>B'10001' # B'01101'</literal>
-        <returnvalue>11100</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>~</literal> <type>bit</type>
-        <returnvalue>bit</returnvalue>
-       </para>
-       <para>
-        Bitwise NOT
-       </para>
-       <para>
-        <literal>~ B'10001'</literal>
-        <returnvalue>01110</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>bit</type> <literal>&lt;&lt;</literal> <type>integer</type>
-        <returnvalue>bit</returnvalue>
-       </para>
-       <para>
-        Bitwise shift left
-        (string length is preserved)
-       </para>
-       <para>
-        <literal>B'10001' &lt;&lt; 3</literal>
-        <returnvalue>01000</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>bit</type> <literal>&gt;&gt;</literal> <type>integer</type>
-        <returnvalue>bit</returnvalue>
-       </para>
-       <para>
-        Bitwise shift right
-        (string length is preserved)
-       </para>
-       <para>
-        <literal>B'10001' &gt;&gt; 2</literal>
-        <returnvalue>00100</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    Some of the functions available for binary strings are also available
-    for bit strings, as shown in <xref linkend="functions-bit-string-table"/>.
-   </para>
-
-   <table id="functions-bit-string-table">
-    <title>Bit String Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>bit_count</primary>
-        </indexterm>
-        <function>bit_count</function> ( <type>bit</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Returns the number of bits set in the bit string (also known as
-        <quote>popcount</quote>).
-       </para>
-       <para>
-        <literal>bit_count(B'10111')</literal>
-        <returnvalue>4</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>bit_length</primary>
-        </indexterm>
-        <function>bit_length</function> ( <type>bit</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns number of bits in the bit string.
-       </para>
-       <para>
-        <literal>bit_length(B'10111')</literal>
-        <returnvalue>5</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>length</primary>
-        </indexterm>
-        <indexterm>
-         <primary>bit string</primary>
-         <secondary>length</secondary>
-        </indexterm>
-        <function>length</function> ( <type>bit</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns number of bits in the bit string.
-       </para>
-       <para>
-        <literal>length(B'10111')</literal>
-        <returnvalue>5</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>octet_length</primary>
-        </indexterm>
-        <function>octet_length</function> ( <type>bit</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns number of bytes in the bit string.
-       </para>
-       <para>
-        <literal>octet_length(B'1011111011')</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>overlay</primary>
-        </indexterm>
-        <function>overlay</function> ( <parameter>bits</parameter> <type>bit</type> <literal>PLACING</literal> <parameter>newsubstring</parameter> <type>bit</type> <literal>FROM</literal> <parameter>start</parameter> <type>integer</type> <optional> <literal>FOR</literal> <parameter>count</parameter> <type>integer</type> </optional> )
-        <returnvalue>bit</returnvalue>
-       </para>
-       <para>
-        Replaces the substring of <parameter>bits</parameter> that starts at
-        the <parameter>start</parameter>'th bit and extends
-        for <parameter>count</parameter> bits
-        with <parameter>newsubstring</parameter>.
-        If <parameter>count</parameter> is omitted, it defaults to the length
-        of <parameter>newsubstring</parameter>.
-       </para>
-       <para>
-        <literal>overlay(B'01010101010101010' placing B'11111' from 2 for 3)</literal>
-        <returnvalue>0111110101010101010</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>position</primary>
-        </indexterm>
-        <function>position</function> ( <parameter>substring</parameter> <type>bit</type> <literal>IN</literal> <parameter>bits</parameter> <type>bit</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns first starting index of the specified <parameter>substring</parameter>
-        within <parameter>bits</parameter>, or zero if it's not present.
-       </para>
-       <para>
-        <literal>position(B'010' in B'000001101011')</literal>
-        <returnvalue>8</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>substring</primary>
-        </indexterm>
-        <function>substring</function> ( <parameter>bits</parameter> <type>bit</type> <optional> <literal>FROM</literal> <parameter>start</parameter> <type>integer</type> </optional> <optional> <literal>FOR</literal> <parameter>count</parameter> <type>integer</type> </optional> )
-        <returnvalue>bit</returnvalue>
-       </para>
-       <para>
-        Extracts the substring of <parameter>bits</parameter> starting at
-        the <parameter>start</parameter>'th bit if that is specified,
-        and stopping after <parameter>count</parameter> bits if that is
-        specified.  Provide at least one of <parameter>start</parameter>
-        and <parameter>count</parameter>.
-       </para>
-       <para>
-        <literal>substring(B'110010111111' from 3 for 2)</literal>
-        <returnvalue>00</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>get_bit</primary>
-        </indexterm>
-        <function>get_bit</function> ( <parameter>bits</parameter> <type>bit</type>,
-        <parameter>n</parameter> <type>integer</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Extracts <parameter>n</parameter>'th bit
-        from bit string; the first (leftmost) bit is bit 0.
-       </para>
-       <para>
-        <literal>get_bit(B'101010101010101010', 6)</literal>
-        <returnvalue>1</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>set_bit</primary>
-        </indexterm>
-        <function>set_bit</function> ( <parameter>bits</parameter> <type>bit</type>,
-        <parameter>n</parameter> <type>integer</type>,
-        <parameter>newvalue</parameter> <type>integer</type> )
-        <returnvalue>bit</returnvalue>
-       </para>
-       <para>
-        Sets <parameter>n</parameter>'th bit in
-        bit string to <parameter>newvalue</parameter>;
-        the first (leftmost) bit is bit 0.
-       </para>
-       <para>
-        <literal>set_bit(B'101010101010101010', 6, 0)</literal>
-        <returnvalue>101010001010101010</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    In addition, it is possible to cast integral values to and from type
-    <type>bit</type>.
-    Casting an integer to <type>bit(n)</type> copies the rightmost
-    <literal>n</literal> bits.  Casting an integer to a bit string width wider
-    than the integer itself will sign-extend on the left.
-    Some examples:
-<programlisting>
-44::bit(10)                    <lineannotation>0000101100</lineannotation>
-44::bit(3)                     <lineannotation>100</lineannotation>
-cast(-44 as bit(12))           <lineannotation>111111010100</lineannotation>
-'1110'::bit(4)::integer        <lineannotation>14</lineannotation>
-</programlisting>
-    Note that casting to just <quote>bit</quote> means casting to
-    <literal>bit(1)</literal>, and so will deliver only the least significant
-    bit of the integer.
-   </para>
-  </sect1>
-
-
- <sect1 id="functions-matching">
-  <title>Pattern Matching</title>
-
-  <indexterm zone="functions-matching">
-   <primary>pattern matching</primary>
-  </indexterm>
-
-   <para>
-    There are three separate approaches to pattern matching provided
-    by <productname>PostgreSQL</productname>: the traditional
-    <acronym>SQL</acronym> <function>LIKE</function> operator, the
-    more recent <function>SIMILAR TO</function> operator (added in
-    SQL:1999), and <acronym>POSIX</acronym>-style regular
-    expressions.  Aside from the basic <quote>does this string match
-    this pattern?</quote> operators, functions are available to extract
-    or replace matching substrings and to split a string at matching
-    locations.
-   </para>
-
-   <tip>
-    <para>
-     If you have pattern matching needs that go beyond this,
-     consider writing a user-defined function in Perl or Tcl.
-    </para>
-   </tip>
-
-   <caution>
-    <para>
-     While most regular-expression searches can be executed very quickly,
-     regular expressions can be contrived that take arbitrary amounts of
-     time and memory to process.  Be wary of accepting regular-expression
-     search patterns from hostile sources.  If you must do so, it is
-     advisable to impose a statement timeout.
-    </para>
-
-    <para>
-     Searches using <function>SIMILAR TO</function> patterns have the same
-     security hazards, since <function>SIMILAR TO</function> provides many
-     of the same capabilities as <acronym>POSIX</acronym>-style regular
-     expressions.
-    </para>
-
-    <para>
-     <function>LIKE</function> searches, being much simpler than the other
-     two options, are safer to use with possibly-hostile pattern sources.
-    </para>
-   </caution>
-
-   <para>
-    <function>SIMILAR TO</function> and <acronym>POSIX</acronym>-style regular
-    expressions do not support nondeterministic collations.  If required, use
-    <function>LIKE</function> or apply a different collation to the expression
-    to work around this limitation.
-   </para>
-
-  <sect2 id="functions-like">
-   <title><function>LIKE</function></title>
-
-   <indexterm>
-    <primary>LIKE</primary>
-   </indexterm>
-
-<synopsis>
-<replaceable>string</replaceable> LIKE <replaceable>pattern</replaceable> <optional>ESCAPE <replaceable>escape-character</replaceable></optional>
-<replaceable>string</replaceable> NOT LIKE <replaceable>pattern</replaceable> <optional>ESCAPE <replaceable>escape-character</replaceable></optional>
-</synopsis>
-
-    <para>
-     The <function>LIKE</function> expression returns true if the
-     <replaceable>string</replaceable> matches the supplied
-     <replaceable>pattern</replaceable>.  (As
-     expected, the <function>NOT LIKE</function> expression returns
-     false if <function>LIKE</function> returns true, and vice versa.
-     An equivalent expression is
-     <literal>NOT (<replaceable>string</replaceable> LIKE
-      <replaceable>pattern</replaceable>)</literal>.)
-    </para>
-
-    <para>
-     If <replaceable>pattern</replaceable> does not contain percent
-     signs or underscores, then the pattern only represents the string
-     itself; in that case <function>LIKE</function> acts like the
-     equals operator.  An underscore (<literal>_</literal>) in
-     <replaceable>pattern</replaceable> stands for (matches) any single
-     character; a percent sign (<literal>%</literal>) matches any sequence
-     of zero or more characters.
-    </para>
-
-   <para>
-    Some examples:
-<programlisting>
-'abc' LIKE 'abc'    <lineannotation>true</lineannotation>
-'abc' LIKE 'a%'     <lineannotation>true</lineannotation>
-'abc' LIKE '_b_'    <lineannotation>true</lineannotation>
-'abc' LIKE 'c'      <lineannotation>false</lineannotation>
-</programlisting>
-   </para>
-
-   <para>
-    <function>LIKE</function> pattern matching supports nondeterministic
-    collations (see <xref linkend="collation-nondeterministic"/>), such as
-    case-insensitive collations or collations that, say, ignore punctuation.
-    So with a case-insensitive collation, one could have:
-<programlisting>
-'AbC' LIKE 'abc' COLLATE case_insensitive    <lineannotation>true</lineannotation>
-'AbC' LIKE 'a%' COLLATE case_insensitive     <lineannotation>true</lineannotation>
-</programlisting>
-    With collations that ignore certain characters or in general that consider
-    strings of different lengths equal, the semantics can become a bit more
-    complicated.  Consider these examples:
-<programlisting>
-'.foo.' LIKE 'foo' COLLATE ign_punct    <lineannotation>true</lineannotation>
-'.foo.' LIKE 'f_o' COLLATE ign_punct    <lineannotation>true</lineannotation>
-'.foo.' LIKE '_oo' COLLATE ign_punct    <lineannotation>false</lineannotation>
-</programlisting>
-    The way the matching works is that the pattern is partitioned into
-    sequences of wildcards and non-wildcard strings (wildcards being
-    <literal>_</literal> and <literal>%</literal>).  For example, the pattern
-    <literal>f_o</literal> is partitioned into <literal>f, _, o</literal>, the
-    pattern <literal>_oo</literal> is partitioned into <literal>_,
-    oo</literal>.  The input string matches the pattern if it can be
-    partitioned in such a way that the wildcards match one character or any
-    number of characters respectively and the non-wildcard partitions are
-    equal under the applicable collation.  So for example, <literal>'.foo.'
-    LIKE 'f_o' COLLATE ign_punct</literal> is true because one can partition
-    <literal>.foo.</literal> into <literal>.f, o, o.</literal>, and then
-    <literal>'.f' = 'f' COLLATE ign_punct</literal>, <literal>'o'</literal>
-    matches the <literal>_</literal> wildcard, and <literal>'o.' = 'o' COLLATE
-    ign_punct</literal>.  But <literal>'.foo.' LIKE '_oo' COLLATE
-    ign_punct</literal> is false because <literal>.foo.</literal> cannot be
-    partitioned in a way that the first character is any character and the
-    rest of the string compares equal to <literal>oo</literal>.  (Note that
-    the single-character wildcard always matches exactly one character,
-    independent of the collation.  So in this example, the
-    <literal>_</literal> would match <literal>.</literal>, but then the rest
-    of the input string won't match the rest of the pattern.)
-   </para>
-
-   <para>
-    <function>LIKE</function> pattern matching always covers the entire
-    string.  Therefore, if it's desired to match a sequence anywhere within
-    a string, the pattern must start and end with a percent sign.
-   </para>
-
-   <para>
-    To match a literal underscore or percent sign without matching
-    other characters, the respective character in
-    <replaceable>pattern</replaceable> must be
-    preceded by the escape character.  The default escape
-    character is the backslash but a different one can be selected by
-    using the <literal>ESCAPE</literal> clause.  To match the escape
-    character itself, write two escape characters.
-   </para>
-
-   <note>
-    <para>
-     If you have <xref linkend="guc-standard-conforming-strings"/> turned off,
-     any backslashes you write in literal string constants will need to be
-     doubled.  See <xref linkend="sql-syntax-strings"/> for more information.
-    </para>
-   </note>
-
-   <para>
-    It's also possible to select no escape character by writing
-    <literal>ESCAPE ''</literal>.  This effectively disables the
-    escape mechanism, which makes it impossible to turn off the
-    special meaning of underscore and percent signs in the pattern.
-   </para>
-
-   <para>
-    According to the SQL standard, omitting <literal>ESCAPE</literal>
-    means there is no escape character (rather than defaulting to a
-    backslash), and a zero-length <literal>ESCAPE</literal> value is
-    disallowed.  <productname>PostgreSQL</productname>'s behavior in
-    this regard is therefore slightly nonstandard.
-   </para>
-
-   <para>
-    The key word <token>ILIKE</token> can be used instead of
-    <token>LIKE</token> to make the match case-insensitive according to the
-    active locale.  (But this does not support nondeterministic collations.)
-    This is not in the <acronym>SQL</acronym> standard but is a
-    <productname>PostgreSQL</productname> extension.
-   </para>
-
-   <para>
-    The operator <literal>~~</literal> is equivalent to
-    <function>LIKE</function>, and <literal>~~*</literal> corresponds to
-    <function>ILIKE</function>.  There are also
-    <literal>!~~</literal> and <literal>!~~*</literal> operators that
-    represent <function>NOT LIKE</function> and <function>NOT
-    ILIKE</function>, respectively.  All of these operators are
-    <productname>PostgreSQL</productname>-specific.  You may see these
-    operator names in <command>EXPLAIN</command> output and similar
-    places, since the parser actually translates <function>LIKE</function>
-    et al. to these operators.
-   </para>
-
-   <para>
-    The phrases <function>LIKE</function>, <function>ILIKE</function>,
-    <function>NOT LIKE</function>, and <function>NOT ILIKE</function> are
-    generally treated as operators
-    in <productname>PostgreSQL</productname> syntax; for example they can
-    be used in <replaceable>expression</replaceable>
-    <replaceable>operator</replaceable> ANY
-    (<replaceable>subquery</replaceable>) constructs, although
-    an <literal>ESCAPE</literal> clause cannot be included there.  In some
-    obscure cases it may be necessary to use the underlying operator names
-    instead.
-   </para>
-
-   <para>
-    Also see the starts-with operator <literal>^@</literal> and the
-    corresponding <function>starts_with()</function> function, which are
-    useful in cases where simply matching the beginning of a string is
-    needed.
-   </para>
-  </sect2>
-
-
-  <sect2 id="functions-similarto-regexp">
-   <title><function>SIMILAR TO</function> Regular Expressions</title>
-
-   <indexterm>
-    <primary>regular expression</primary>
-    <!-- <seealso>pattern matching</seealso> breaks index build -->
-   </indexterm>
-
-   <indexterm>
-    <primary>SIMILAR TO</primary>
-   </indexterm>
-   <indexterm>
-    <primary>substring</primary>
-   </indexterm>
-
-<synopsis>
-<replaceable>string</replaceable> SIMILAR TO <replaceable>pattern</replaceable> <optional>ESCAPE <replaceable>escape-character</replaceable></optional>
-<replaceable>string</replaceable> NOT SIMILAR TO <replaceable>pattern</replaceable> <optional>ESCAPE <replaceable>escape-character</replaceable></optional>
-</synopsis>
-
-   <para>
-    The <function>SIMILAR TO</function> operator returns true or
-    false depending on whether its pattern matches the given string.
-    It is similar to <function>LIKE</function>, except that it
-    interprets the pattern using the SQL standard's definition of a
-    regular expression.  SQL regular expressions are a curious cross
-    between <function>LIKE</function> notation and common (POSIX) regular
-    expression notation.
-   </para>
-
-   <para>
-    Like <function>LIKE</function>, the <function>SIMILAR TO</function>
-    operator succeeds only if its pattern matches the entire string;
-    this is unlike common regular expression behavior where the pattern
-    can match any part of the string.
-    Also like
-    <function>LIKE</function>, <function>SIMILAR TO</function> uses
-    <literal>_</literal> and <literal>%</literal> as wildcard characters denoting
-    any single character and any string, respectively (these are
-    comparable to <literal>.</literal> and <literal>.*</literal> in POSIX regular
-    expressions).
-   </para>
-
-   <para>
-    In addition to these facilities borrowed from <function>LIKE</function>,
-    <function>SIMILAR TO</function> supports these pattern-matching
-    metacharacters borrowed from POSIX regular expressions:
-
-   <itemizedlist>
-    <listitem>
-     <para>
-      <literal>|</literal> denotes alternation (either of two alternatives).
-     </para>
-    </listitem>
-    <listitem>
-     <para>
-      <literal>*</literal> denotes repetition of the previous item zero
-      or more times.
-     </para>
-    </listitem>
-    <listitem>
-     <para>
-      <literal>+</literal> denotes repetition of the previous item one
-      or more times.
-     </para>
-    </listitem>
-    <listitem>
-     <para>
-      <literal>?</literal> denotes repetition of the previous item zero
-      or one time.
-     </para>
-    </listitem>
-    <listitem>
-     <para>
-      <literal>{</literal><replaceable>m</replaceable><literal>}</literal> denotes repetition
-      of the previous item exactly <replaceable>m</replaceable> times.
-     </para>
-    </listitem>
-    <listitem>
-     <para>
-      <literal>{</literal><replaceable>m</replaceable><literal>,}</literal> denotes repetition
-      of the previous item <replaceable>m</replaceable> or more times.
-     </para>
-    </listitem>
-    <listitem>
-     <para>
-      <literal>{</literal><replaceable>m</replaceable><literal>,</literal><replaceable>n</replaceable><literal>}</literal>
-      denotes repetition of the previous item at least <replaceable>m</replaceable> and
-      not more than <replaceable>n</replaceable> times.
-     </para>
-    </listitem>
-    <listitem>
-     <para>
-      Parentheses <literal>()</literal> can be used to group items into
-      a single logical item.
-     </para>
-    </listitem>
-    <listitem>
-     <para>
-      A bracket expression <literal>[...]</literal> specifies a character
-      class, just as in POSIX regular expressions.
-     </para>
-    </listitem>
-   </itemizedlist>
-
-    Notice that the period (<literal>.</literal>) is not a metacharacter
-    for <function>SIMILAR TO</function>.
-   </para>
-
-   <para>
-    As with <function>LIKE</function>, a backslash disables the special
-    meaning of any of these metacharacters.  A different escape character
-    can be specified with <literal>ESCAPE</literal>, or the escape
-    capability can be disabled by writing <literal>ESCAPE ''</literal>.
-   </para>
-
-   <para>
-    According to the SQL standard, omitting <literal>ESCAPE</literal>
-    means there is no escape character (rather than defaulting to a
-    backslash), and a zero-length <literal>ESCAPE</literal> value is
-    disallowed.  <productname>PostgreSQL</productname>'s behavior in
-    this regard is therefore slightly nonstandard.
-   </para>
-
-   <para>
-    Another nonstandard extension is that following the escape character
-    with a letter or digit provides access to the escape sequences
-    defined for POSIX regular expressions; see
-    <xref linkend="posix-character-entry-escapes-table"/>,
-    <xref linkend="posix-class-shorthand-escapes-table"/>, and
-    <xref linkend="posix-constraint-escapes-table"/> below.
-   </para>
-
-   <para>
-    Some examples:
-<programlisting>
-'abc' SIMILAR TO 'abc'          <lineannotation>true</lineannotation>
-'abc' SIMILAR TO 'a'            <lineannotation>false</lineannotation>
-'abc' SIMILAR TO '%(b|d)%'      <lineannotation>true</lineannotation>
-'abc' SIMILAR TO '(b|c)%'       <lineannotation>false</lineannotation>
-'-abc-' SIMILAR TO '%\mabc\M%'  <lineannotation>true</lineannotation>
-'xabcy' SIMILAR TO '%\mabc\M%'  <lineannotation>false</lineannotation>
-</programlisting>
-   </para>
-
-   <para>
-    The <function>substring</function> function with three parameters
-    provides extraction of a substring that matches an SQL
-    regular expression pattern.  The function can be written according
-    to standard SQL syntax:
-<synopsis>
-substring(<replaceable>string</replaceable> similar <replaceable>pattern</replaceable> escape <replaceable>escape-character</replaceable>)
-</synopsis>
-    or using the now obsolete SQL:1999 syntax:
-<synopsis>
-substring(<replaceable>string</replaceable> from <replaceable>pattern</replaceable> for <replaceable>escape-character</replaceable>)
-</synopsis>
-    or as a plain three-argument function:
-<synopsis>
-substring(<replaceable>string</replaceable>, <replaceable>pattern</replaceable>, <replaceable>escape-character</replaceable>)
-</synopsis>
-    As with <literal>SIMILAR TO</literal>, the
-    specified pattern must match the entire data string, or else the
-    function fails and returns null.  To indicate the part of the
-    pattern for which the matching data sub-string is of interest,
-    the pattern should contain
-    two occurrences of the escape character followed by a double quote
-    (<literal>"</literal>). <!-- " font-lock sanity -->
-    The text matching the portion of the pattern
-    between these separators is returned when the match is successful.
-   </para>
-
-   <para>
-    The escape-double-quote separators actually
-    divide <function>substring</function>'s pattern into three independent
-    regular expressions; for example, a vertical bar (<literal>|</literal>)
-    in any of the three sections affects only that section.  Also, the first
-    and third of these regular expressions are defined to match the smallest
-    possible amount of text, not the largest, when there is any ambiguity
-    about how much of the data string matches which pattern.  (In POSIX
-    parlance, the first and third regular expressions are forced to be
-    non-greedy.)
-   </para>
-
-   <para>
-    As an extension to the SQL standard, <productname>PostgreSQL</productname>
-    allows there to be just one escape-double-quote separator, in which case
-    the third regular expression is taken as empty; or no separators, in which
-    case the first and third regular expressions are taken as empty.
-   </para>
-
-   <para>
-    Some examples, with <literal>#&quot;</literal> delimiting the return string:
-<programlisting>
-substring('foobar' similar '%#"o_b#"%' escape '#')   <lineannotation>oob</lineannotation>
-substring('foobar' similar '#"o_b#"%' escape '#')    <lineannotation>NULL</lineannotation>
-</programlisting>
-   </para>
-  </sect2>
-
-  <sect2 id="functions-posix-regexp">
-   <title><acronym>POSIX</acronym> Regular Expressions</title>
-
-   <indexterm zone="functions-posix-regexp">
-    <primary>regular expression</primary>
-    <seealso>pattern matching</seealso>
-   </indexterm>
-   <indexterm>
-    <primary>substring</primary>
-   </indexterm>
-   <indexterm>
-    <primary>regexp_count</primary>
-   </indexterm>
-   <indexterm>
-    <primary>regexp_instr</primary>
-   </indexterm>
-   <indexterm>
-    <primary>regexp_like</primary>
-   </indexterm>
-   <indexterm>
-    <primary>regexp_match</primary>
-   </indexterm>
-   <indexterm>
-    <primary>regexp_matches</primary>
-   </indexterm>
-   <indexterm>
-    <primary>regexp_replace</primary>
-   </indexterm>
-   <indexterm>
-    <primary>regexp_split_to_table</primary>
-   </indexterm>
-   <indexterm>
-    <primary>regexp_split_to_array</primary>
-   </indexterm>
-   <indexterm>
-    <primary>regexp_substr</primary>
-   </indexterm>
-
-   <para>
-    <xref linkend="functions-posix-table"/> lists the available
-    operators for pattern matching using POSIX regular expressions.
-   </para>
-
-   <table id="functions-posix-table">
-    <title>Regular Expression Match Operators</title>
-
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Operator
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-      <tbody>
-       <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>text</type> <literal>~</literal> <type>text</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        String matches regular expression, case sensitively
-       </para>
-       <para>
-        <literal>'thomas' ~ 't.*ma'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-       </row>
-
-       <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>text</type> <literal>~*</literal> <type>text</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        String matches regular expression, case-insensitively
-       </para>
-       <para>
-        <literal>'thomas' ~* 'T.*ma'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-       </row>
-
-       <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>text</type> <literal>!~</literal> <type>text</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        String does not match regular expression, case sensitively
-       </para>
-       <para>
-        <literal>'thomas' !~ 't.*max'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-       </row>
-
-       <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>text</type> <literal>!~*</literal> <type>text</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        String does not match regular expression, case-insensitively
-       </para>
-       <para>
-        <literal>'thomas' !~* 'T.*ma'</literal>
-        <returnvalue>f</returnvalue>
-       </para></entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-    <para>
-     <acronym>POSIX</acronym> regular expressions provide a more
-     powerful means for pattern matching than the <function>LIKE</function> and
-     <function>SIMILAR TO</function> operators.
-     Many Unix tools such as <command>egrep</command>,
-     <command>sed</command>, or <command>awk</command> use a pattern
-     matching language that is similar to the one described here.
-    </para>
-
-    <para>
-     A regular expression is a character sequence that is an
-     abbreviated definition of a set of strings (a <firstterm>regular
-     set</firstterm>).  A string is said to match a regular expression
-     if it is a member of the regular set described by the regular
-     expression.  As with <function>LIKE</function>, pattern characters
-     match string characters exactly unless they are special characters
-     in the regular expression language &mdash; but regular expressions use
-     different special characters than <function>LIKE</function> does.
-     Unlike <function>LIKE</function> patterns, a
-     regular expression is allowed to match anywhere within a string, unless
-     the regular expression is explicitly anchored to the beginning or
-     end of the string.
-    </para>
-
-    <para>
-     Some examples:
-<programlisting>
-'abcd' ~ 'bc'     <lineannotation>true</lineannotation>
-'abcd' ~ 'a.c'    <lineannotation>true &mdash; dot matches any character</lineannotation>
-'abcd' ~ 'a.*d'   <lineannotation>true &mdash; <literal>*</literal> repeats the preceding pattern item</lineannotation>
-'abcd' ~ '(b|x)'  <lineannotation>true &mdash; <literal>|</literal> means OR, parentheses group</lineannotation>
-'abcd' ~ '^a'     <lineannotation>true &mdash; <literal>^</literal> anchors to start of string</lineannotation>
-'abcd' ~ '^(b|c)' <lineannotation>false &mdash; would match except for anchoring</lineannotation>
-</programlisting>
-    </para>
-
-    <para>
-     The <acronym>POSIX</acronym> pattern language is described in much
-     greater detail below.
-    </para>
-
-    <para>
-     The <function>substring</function> function with two parameters,
-     <function>substring(<replaceable>string</replaceable> from
-     <replaceable>pattern</replaceable>)</function>, provides extraction of a
-     substring
-     that matches a POSIX regular expression pattern.  It returns null if
-     there is no match, otherwise the first portion of the text that matched the
-     pattern.  But if the pattern contains any parentheses, the portion
-     of the text that matched the first parenthesized subexpression (the
-     one whose left parenthesis comes first) is
-     returned.  You can put parentheses around the whole expression
-     if you want to use parentheses within it without triggering this
-     exception.  If you need parentheses in the pattern before the
-     subexpression you want to extract, see the non-capturing parentheses
-     described below.
-    </para>
-
-   <para>
-    Some examples:
-<programlisting>
-substring('foobar' from 'o.b')     <lineannotation>oob</lineannotation>
-substring('foobar' from 'o(.)b')   <lineannotation>o</lineannotation>
-</programlisting>
-   </para>
-
-    <para>
-     The <function>regexp_count</function> function counts the number of
-     places where a POSIX regular expression pattern matches a string.
-     It has the syntax
-     <function>regexp_count</function>(<replaceable>string</replaceable>,
-     <replaceable>pattern</replaceable>
-     <optional>, <replaceable>start</replaceable>
-     <optional>, <replaceable>flags</replaceable>
-     </optional></optional>).
-     <replaceable>pattern</replaceable> is searched for
-     in <replaceable>string</replaceable>, normally from the beginning of
-     the string, but if the <replaceable>start</replaceable> parameter is
-     provided then beginning from that character index.
-     The <replaceable>flags</replaceable> parameter is an optional text
-     string containing zero or more single-letter flags that change the
-     function's behavior.  For example, including <literal>i</literal> in
-     <replaceable>flags</replaceable> specifies case-insensitive matching.
-     Supported flags are described in
-     <xref linkend="posix-embedded-options-table"/>.
-    </para>
-
-    <para>
-     Some examples:
-<programlisting>
-regexp_count('ABCABCAXYaxy', 'A.')          <lineannotation>3</lineannotation>
-regexp_count('ABCABCAXYaxy', 'A.', 1, 'i')  <lineannotation>4</lineannotation>
-</programlisting>
-    </para>
-
-    <para>
-     The <function>regexp_instr</function> function returns the starting or
-     ending position of the <replaceable>N</replaceable>'th match of a
-     POSIX regular expression pattern to a string, or zero if there is no
-     such match.  It has the syntax
-     <function>regexp_instr</function>(<replaceable>string</replaceable>,
-     <replaceable>pattern</replaceable>
-     <optional>, <replaceable>start</replaceable>
-     <optional>, <replaceable>N</replaceable>
-     <optional>, <replaceable>endoption</replaceable>
-     <optional>, <replaceable>flags</replaceable>
-     <optional>, <replaceable>subexpr</replaceable>
-     </optional></optional></optional></optional></optional>).
-     <replaceable>pattern</replaceable> is searched for
-     in <replaceable>string</replaceable>, normally from the beginning of
-     the string, but if the <replaceable>start</replaceable> parameter is
-     provided then beginning from that character index.
-     If <replaceable>N</replaceable> is specified
-     then the <replaceable>N</replaceable>'th match of the pattern
-     is located, otherwise the first match is located.
-     If the <replaceable>endoption</replaceable> parameter is omitted or
-     specified as zero, the function returns the position of the first
-     character of the match.  Otherwise, <replaceable>endoption</replaceable>
-     must be one, and the function returns the position of the character
-     following the match.
-     The <replaceable>flags</replaceable> parameter is an optional text
-     string containing zero or more single-letter flags that change the
-     function's behavior.  Supported flags are described
-     in <xref linkend="posix-embedded-options-table"/>.
-     For a pattern containing parenthesized
-     subexpressions, <replaceable>subexpr</replaceable> is an integer
-     indicating which subexpression is of interest: the result identifies
-     the position of the substring matching that subexpression.
-     Subexpressions are numbered in the order of their leading parentheses.
-     When <replaceable>subexpr</replaceable> is omitted or zero, the result
-     identifies the position of the whole match regardless of
-     parenthesized subexpressions.
-    </para>
-
-    <para>
-     Some examples:
-<programlisting>
-regexp_instr('number of your street, town zip, FR', '[^,]+', 1, 2)
-                                   <lineannotation>23</lineannotation>
-regexp_instr(string=>'ABCDEFGHI', pattern=>'(c..)(...)', start=>1, "N"=>1, endoption=>0, flags=>'i', subexpr=>2)
-                                   <lineannotation>6</lineannotation>
-</programlisting>
-    </para>
-
-    <para>
-     The <function>regexp_like</function> function checks whether a match
-     of a POSIX regular expression pattern occurs within a string,
-     returning boolean true or false.  It has the syntax
-     <function>regexp_like</function>(<replaceable>string</replaceable>,
-     <replaceable>pattern</replaceable>
-     <optional>, <replaceable>flags</replaceable> </optional>).
-     The <replaceable>flags</replaceable> parameter is an optional text
-     string containing zero or more single-letter flags that change the
-     function's behavior.  Supported flags are described
-     in <xref linkend="posix-embedded-options-table"/>.
-     This function has the same results as the <literal>~</literal>
-     operator if no flags are specified.  If only the <literal>i</literal>
-     flag is specified, it has the same results as
-     the <literal>~*</literal> operator.
-    </para>
-
-    <para>
-     Some examples:
-<programlisting>
-regexp_like('Hello World', 'world')       <lineannotation>false</lineannotation>
-regexp_like('Hello World', 'world', 'i')  <lineannotation>true</lineannotation>
-</programlisting>
-    </para>
-
-    <para>
-     The <function>regexp_match</function> function returns a text array of
-     matching substring(s) within the first match of a POSIX
-     regular expression pattern to a string.  It has the syntax
-     <function>regexp_match</function>(<replaceable>string</replaceable>,
-     <replaceable>pattern</replaceable> <optional>, <replaceable>flags</replaceable> </optional>).
-     If there is no match, the result is <literal>NULL</literal>.
-     If a match is found, and the <replaceable>pattern</replaceable> contains no
-     parenthesized subexpressions, then the result is a single-element text
-     array containing the substring matching the whole pattern.
-     If a match is found, and the <replaceable>pattern</replaceable> contains
-     parenthesized subexpressions, then the result is a text array
-     whose <replaceable>n</replaceable>'th element is the substring matching
-     the <replaceable>n</replaceable>'th parenthesized subexpression of
-     the <replaceable>pattern</replaceable> (not counting <quote>non-capturing</quote>
-     parentheses; see below for details).
-     The <replaceable>flags</replaceable> parameter is an optional text string
-     containing zero or more single-letter flags that change the function's
-     behavior.  Supported flags are described
-     in <xref linkend="posix-embedded-options-table"/>.
-    </para>
-
-   <para>
-    Some examples:
-<programlisting>
-SELECT regexp_match('foobarbequebaz', 'bar.*que');
- regexp_match
---------------
- {barbeque}
-(1 row)
-
-SELECT regexp_match('foobarbequebaz', '(bar)(beque)');
- regexp_match
---------------
- {bar,beque}
-(1 row)
-</programlisting>
-   </para>
-
-    <tip>
-     <para>
-      In the common case where you just want the whole matching substring
-      or <literal>NULL</literal> for no match, the best solution is to
-      use <function>regexp_substr()</function>.
-      However, <function>regexp_substr()</function> only exists
-      in <productname>PostgreSQL</productname> version 15 and up.  When
-      working in older versions, you can extract the first element
-      of <function>regexp_match()</function>'s result, for example:
-<programlisting>
-SELECT (regexp_match('foobarbequebaz', 'bar.*que'))[1];
- regexp_match
---------------
- barbeque
-(1 row)
-</programlisting>
-     </para>
-    </tip>
-
-    <para>
-     The <function>regexp_matches</function> function returns a set of text arrays
-     of matching substring(s) within matches of a POSIX regular
-     expression pattern to a string.  It has the same syntax as
-     <function>regexp_match</function>.
-     This function returns no rows if there is no match, one row if there is
-     a match and the <literal>g</literal> flag is not given, or <replaceable>N</replaceable>
-     rows if there are <replaceable>N</replaceable> matches and the <literal>g</literal> flag
-     is given.  Each returned row is a text array containing the whole
-     matched substring or the substrings matching parenthesized
-     subexpressions of the <replaceable>pattern</replaceable>, just as described above
-     for <function>regexp_match</function>.
-     <function>regexp_matches</function> accepts all the flags shown
-     in <xref linkend="posix-embedded-options-table"/>, plus
-     the <literal>g</literal> flag which commands it to return all matches, not
-     just the first one.
-    </para>
-
-   <para>
-    Some examples:
-<programlisting>
-SELECT regexp_matches('foo', 'not there');
- regexp_matches
-----------------
-(0 rows)
-
-SELECT regexp_matches('foobarbequebazilbarfbonk', '(b[^b]+)(b[^b]+)', 'g');
- regexp_matches
-----------------
- {bar,beque}
- {bazil,barf}
-(2 rows)
-</programlisting>
-   </para>
-
-   <tip>
-    <para>
-     In most cases <function>regexp_matches()</function> should be used with
-     the <literal>g</literal> flag, since if you only want the first match, it's
-     easier and more efficient to use <function>regexp_match()</function>.
-     However, <function>regexp_match()</function> only exists
-     in <productname>PostgreSQL</productname> version 10 and up.  When working in older
-     versions, a common trick is to place a <function>regexp_matches()</function>
-     call in a sub-select, for example:
-<programlisting>
-SELECT col1, (SELECT regexp_matches(col2, '(bar)(beque)')) FROM tab;
-</programlisting>
-     This produces a text array if there's a match, or <literal>NULL</literal> if
-     not, the same as <function>regexp_match()</function> would do.  Without the
-     sub-select, this query would produce no output at all for table rows
-     without a match, which is typically not the desired behavior.
-    </para>
-   </tip>
-
-    <para>
-     The <function>regexp_replace</function> function provides substitution of
-     new text for substrings that match POSIX regular expression patterns.
-     It has the syntax
-     <function>regexp_replace</function>(<replaceable>string</replaceable>,
-     <replaceable>pattern</replaceable>, <replaceable>replacement</replaceable>
-     <optional>, <replaceable>flags</replaceable> </optional>)
-     or
-     <function>regexp_replace</function>(<replaceable>string</replaceable>,
-     <replaceable>pattern</replaceable>, <replaceable>replacement</replaceable>,
-     <replaceable>start</replaceable>
-     <optional>, <replaceable>N</replaceable>
-     <optional>, <replaceable>flags</replaceable> </optional></optional>).
-     The source <replaceable>string</replaceable> is returned unchanged if
-     there is no match to the <replaceable>pattern</replaceable>.  If there is a
-     match, the <replaceable>string</replaceable> is returned with the
-     <replaceable>replacement</replaceable> string substituted for the matching
-     substring.  The <replaceable>replacement</replaceable> string can contain
-     <literal>\</literal><replaceable>n</replaceable>, where <replaceable>n</replaceable> is 1
-     through 9, to indicate that the source substring matching the
-     <replaceable>n</replaceable>'th parenthesized subexpression of the pattern should be
-     inserted, and it can contain <literal>\&amp;</literal> to indicate that the
-     substring matching the entire pattern should be inserted.  Write
-     <literal>\\</literal> if you need to put a literal backslash in the replacement
-     text.
-     <replaceable>pattern</replaceable> is searched for
-     in <replaceable>string</replaceable>, normally from the beginning of
-     the string, but if the <replaceable>start</replaceable> parameter is
-     provided then beginning from that character index.
-     By default, only the first match of the pattern is replaced.
-     If <replaceable>N</replaceable> is specified and is greater than zero,
-     then the <replaceable>N</replaceable>'th match of the pattern
-     is replaced.
-     If the <literal>g</literal> flag is given, or
-     if <replaceable>N</replaceable> is specified and is zero, then all
-     matches at or after the <replaceable>start</replaceable> position are
-     replaced.  (The <literal>g</literal> flag is ignored
-     when <replaceable>N</replaceable> is specified.)
-     The <replaceable>flags</replaceable> parameter is an optional text
-     string containing zero or more single-letter flags that change the
-     function's behavior.  Supported flags (though
-     not <literal>g</literal>) are
-     described in <xref linkend="posix-embedded-options-table"/>.
-    </para>
-
-   <para>
-    Some examples:
-<programlisting>
-regexp_replace('foobarbaz', 'b..', 'X')
-                                   <lineannotation>fooXbaz</lineannotation>
-regexp_replace('foobarbaz', 'b..', 'X', 'g')
-                                   <lineannotation>fooXX</lineannotation>
-regexp_replace('foobarbaz', 'b(..)', 'X\1Y', 'g')
-                                   <lineannotation>fooXarYXazY</lineannotation>
-regexp_replace('A PostgreSQL function', 'a|e|i|o|u', 'X', 1, 0, 'i')
-                                   <lineannotation>X PXstgrXSQL fXnctXXn</lineannotation>
-regexp_replace(string=>'A PostgreSQL function', pattern=>'a|e|i|o|u', replacement=>'X', start=>1, "N"=>3, flags=>'i')
-                                   <lineannotation>A PostgrXSQL function</lineannotation>
-</programlisting>
-   </para>
-
-    <para>
-     The <function>regexp_split_to_table</function> function splits a string using a POSIX
-     regular expression pattern as a delimiter.  It has the syntax
-     <function>regexp_split_to_table</function>(<replaceable>string</replaceable>, <replaceable>pattern</replaceable>
-     <optional>, <replaceable>flags</replaceable> </optional>).
-     If there is no match to the <replaceable>pattern</replaceable>, the function returns the
-     <replaceable>string</replaceable>.  If there is at least one match, for each match it returns
-     the text from the end of the last match (or the beginning of the string)
-     to the beginning of the match.  When there are no more matches, it
-     returns the text from the end of the last match to the end of the string.
-     The <replaceable>flags</replaceable> parameter is an optional text string containing
-     zero or more single-letter flags that change the function's behavior.
-     <function>regexp_split_to_table</function> supports the flags described in
-     <xref linkend="posix-embedded-options-table"/>.
-    </para>
-
-    <para>
-     The <function>regexp_split_to_array</function> function behaves the same as
-     <function>regexp_split_to_table</function>, except that <function>regexp_split_to_array</function>
-     returns its result as an array of <type>text</type>.  It has the syntax
-     <function>regexp_split_to_array</function>(<replaceable>string</replaceable>, <replaceable>pattern</replaceable>
-     <optional>, <replaceable>flags</replaceable> </optional>).
-     The parameters are the same as for <function>regexp_split_to_table</function>.
-    </para>
-
-   <para>
-    Some examples:
-<programlisting>
-SELECT foo FROM regexp_split_to_table('the quick brown fox jumps over the lazy dog', '\s+') AS foo;
-  foo
--------
- the
- quick
- brown
- fox
- jumps
- over
- the
- lazy
- dog
-(9 rows)
-
-SELECT regexp_split_to_array('the quick brown fox jumps over the lazy dog', '\s+');
-              regexp_split_to_array
------------------------------------------------
- {the,quick,brown,fox,jumps,over,the,lazy,dog}
-(1 row)
-
-SELECT foo FROM regexp_split_to_table('the quick brown fox', '\s*') AS foo;
- foo
------
- t
- h
- e
- q
- u
- i
- c
- k
- b
- r
- o
- w
- n
- f
- o
- x
-(16 rows)
-</programlisting>
-   </para>
-
-   <para>
-    As the last example demonstrates, the regexp split functions ignore
-    zero-length matches that occur at the start or end of the string
-    or immediately after a previous match.  This is contrary to the strict
-    definition of regexp matching that is implemented by
-    the other regexp functions, but is usually the most convenient behavior
-    in practice.  Other software systems such as Perl use similar definitions.
-   </para>
-
-    <para>
-     The <function>regexp_substr</function> function returns the substring
-     that matches a POSIX regular expression pattern,
-     or <literal>NULL</literal> if there is no match.  It has the syntax
-     <function>regexp_substr</function>(<replaceable>string</replaceable>,
-     <replaceable>pattern</replaceable>
-     <optional>, <replaceable>start</replaceable>
-     <optional>, <replaceable>N</replaceable>
-     <optional>, <replaceable>flags</replaceable>
-     <optional>, <replaceable>subexpr</replaceable>
-     </optional></optional></optional></optional>).
-     <replaceable>pattern</replaceable> is searched for
-     in <replaceable>string</replaceable>, normally from the beginning of
-     the string, but if the <replaceable>start</replaceable> parameter is
-     provided then beginning from that character index.
-     If <replaceable>N</replaceable> is specified
-     then the <replaceable>N</replaceable>'th match of the pattern
-     is returned, otherwise the first match is returned.
-     The <replaceable>flags</replaceable> parameter is an optional text
-     string containing zero or more single-letter flags that change the
-     function's behavior.  Supported flags are described
-     in <xref linkend="posix-embedded-options-table"/>.
-     For a pattern containing parenthesized
-     subexpressions, <replaceable>subexpr</replaceable> is an integer
-     indicating which subexpression is of interest: the result is the
-     substring matching that subexpression.
-     Subexpressions are numbered in the order of their leading parentheses.
-     When <replaceable>subexpr</replaceable> is omitted or zero, the result
-     is the whole match regardless of parenthesized subexpressions.
-    </para>
-
-    <para>
-     Some examples:
-<programlisting>
-regexp_substr('number of your street, town zip, FR', '[^,]+', 1, 2)
-                                   <lineannotation> town zip</lineannotation>
-regexp_substr('ABCDEFGHI', '(c..)(...)', 1, 1, 'i', 2)
-                                   <lineannotation>FGH</lineannotation>
-</programlisting>
-    </para>
-
-<!-- derived from the re_syntax.n man page -->
-
-   <sect3 id="posix-syntax-details">
-    <title>Regular Expression Details</title>
-
-   <para>
-    <productname>PostgreSQL</productname>'s regular expressions are implemented
-    using a software package written by Henry Spencer.  Much of
-    the description of regular expressions below is copied verbatim from his
-    manual.
-   </para>
-
-   <para>
-    Regular expressions (<acronym>RE</acronym>s), as defined in
-    <acronym>POSIX</acronym> 1003.2, come in two forms:
-    <firstterm>extended</firstterm> <acronym>RE</acronym>s or <acronym>ERE</acronym>s
-    (roughly those of <command>egrep</command>), and
-    <firstterm>basic</firstterm> <acronym>RE</acronym>s or <acronym>BRE</acronym>s
-    (roughly those of <command>ed</command>).
-    <productname>PostgreSQL</productname> supports both forms, and
-    also implements some extensions
-    that are not in the POSIX standard, but have become widely used
-    due to their availability in programming languages such as Perl and Tcl.
-    <acronym>RE</acronym>s using these non-POSIX extensions are called
-    <firstterm>advanced</firstterm> <acronym>RE</acronym>s or <acronym>ARE</acronym>s
-    in this documentation.  AREs are almost an exact superset of EREs,
-    but BREs have several notational incompatibilities (as well as being
-    much more limited).
-    We first describe the ARE and ERE forms, noting features that apply
-    only to AREs, and then describe how BREs differ.
-   </para>
-
-   <note>
-    <para>
-     <productname>PostgreSQL</productname> always initially presumes that a regular
-     expression follows the ARE rules.  However, the more limited ERE or
-     BRE rules can be chosen by prepending an <firstterm>embedded option</firstterm>
-     to the RE pattern, as described in <xref linkend="posix-metasyntax"/>.
-     This can be useful for compatibility with applications that expect
-     exactly the <acronym>POSIX</acronym> 1003.2 rules.
-    </para>
-   </note>
-
-   <para>
-    A regular expression is defined as one or more
-    <firstterm>branches</firstterm>, separated by
-    <literal>|</literal>.  It matches anything that matches one of the
-    branches.
-   </para>
-
-   <para>
-    A branch is zero or more <firstterm>quantified atoms</firstterm> or
-    <firstterm>constraints</firstterm>, concatenated.
-    It matches a match for the first, followed by a match for the second, etc.;
-    an empty branch matches the empty string.
-   </para>
-
-   <para>
-    A quantified atom is an <firstterm>atom</firstterm> possibly followed
-    by a single <firstterm>quantifier</firstterm>.
-    Without a quantifier, it matches a match for the atom.
-    With a quantifier, it can match some number of matches of the atom.
-    An <firstterm>atom</firstterm> can be any of the possibilities
-    shown in <xref linkend="posix-atoms-table"/>.
-    The possible quantifiers and their meanings are shown in
-    <xref linkend="posix-quantifiers-table"/>.
-   </para>
-
-   <para>
-    A <firstterm>constraint</firstterm> matches an empty string, but matches only when
-    specific conditions are met.  A constraint can be used where an atom
-    could be used, except it cannot be followed by a quantifier.
-    The simple constraints are shown in
-    <xref linkend="posix-constraints-table"/>;
-    some more constraints are described later.
-   </para>
-
-
-   <table id="posix-atoms-table">
-    <title>Regular Expression Atoms</title>
-
-    <tgroup cols="2">
-     <thead>
-      <row>
-       <entry>Atom</entry>
-       <entry>Description</entry>
-      </row>
-     </thead>
-
-      <tbody>
-       <row>
-       <entry> <literal>(</literal><replaceable>re</replaceable><literal>)</literal> </entry>
-       <entry> (where <replaceable>re</replaceable> is any regular expression)
-       matches a match for
-       <replaceable>re</replaceable>, with the match noted for possible reporting </entry>
-       </row>
-
-       <row>
-       <entry> <literal>(?:</literal><replaceable>re</replaceable><literal>)</literal> </entry>
-       <entry> as above, but the match is not noted for reporting
-       (a <quote>non-capturing</quote> set of parentheses)
-       (AREs only) </entry>
-       </row>
-
-       <row>
-       <entry> <literal>.</literal> </entry>
-       <entry> matches any single character </entry>
-       </row>
-
-       <row>
-       <entry> <literal>[</literal><replaceable>chars</replaceable><literal>]</literal> </entry>
-       <entry> a <firstterm>bracket expression</firstterm>,
-       matching any one of the <replaceable>chars</replaceable> (see
-       <xref linkend="posix-bracket-expressions"/> for more detail) </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\</literal><replaceable>k</replaceable> </entry>
-       <entry> (where <replaceable>k</replaceable> is a non-alphanumeric character)
-       matches that character taken as an ordinary character,
-       e.g., <literal>\\</literal> matches a backslash character </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\</literal><replaceable>c</replaceable> </entry>
-       <entry> where <replaceable>c</replaceable> is alphanumeric
-       (possibly followed by other characters)
-       is an <firstterm>escape</firstterm>, see <xref linkend="posix-escape-sequences"/>
-       (AREs only; in EREs and BREs, this matches <replaceable>c</replaceable>) </entry>
-       </row>
-
-       <row>
-       <entry> <literal>{</literal> </entry>
-       <entry> when followed by a character other than a digit,
-       matches the left-brace character <literal>{</literal>;
-       when followed by a digit, it is the beginning of a
-       <replaceable>bound</replaceable> (see below) </entry>
-       </row>
-
-       <row>
-       <entry> <replaceable>x</replaceable> </entry>
-       <entry> where <replaceable>x</replaceable> is a single character with no other
-       significance, matches that character </entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-   <para>
-    An RE cannot end with a backslash (<literal>\</literal>).
-   </para>
-
-   <note>
-    <para>
-     If you have <xref linkend="guc-standard-conforming-strings"/> turned off,
-     any backslashes you write in literal string constants will need to be
-     doubled.  See <xref linkend="sql-syntax-strings"/> for more information.
-    </para>
-   </note>
-
-   <table id="posix-quantifiers-table">
-    <title>Regular Expression Quantifiers</title>
-
-    <tgroup cols="2">
-     <thead>
-      <row>
-       <entry>Quantifier</entry>
-       <entry>Matches</entry>
-      </row>
-     </thead>
-
-      <tbody>
-       <row>
-       <entry> <literal>*</literal> </entry>
-       <entry> a sequence of 0 or more matches of the atom </entry>
-       </row>
-
-       <row>
-       <entry> <literal>+</literal> </entry>
-       <entry> a sequence of 1 or more matches of the atom </entry>
-       </row>
-
-       <row>
-       <entry> <literal>?</literal> </entry>
-       <entry> a sequence of 0 or 1 matches of the atom </entry>
-       </row>
-
-       <row>
-       <entry> <literal>{</literal><replaceable>m</replaceable><literal>}</literal> </entry>
-       <entry> a sequence of exactly <replaceable>m</replaceable> matches of the atom </entry>
-       </row>
-
-       <row>
-       <entry> <literal>{</literal><replaceable>m</replaceable><literal>,}</literal> </entry>
-       <entry> a sequence of <replaceable>m</replaceable> or more matches of the atom </entry>
-       </row>
-
-       <row>
-       <entry>
-       <literal>{</literal><replaceable>m</replaceable><literal>,</literal><replaceable>n</replaceable><literal>}</literal> </entry>
-       <entry> a sequence of <replaceable>m</replaceable> through <replaceable>n</replaceable>
-       (inclusive) matches of the atom; <replaceable>m</replaceable> cannot exceed
-       <replaceable>n</replaceable> </entry>
-       </row>
-
-       <row>
-       <entry> <literal>*?</literal> </entry>
-       <entry> non-greedy version of <literal>*</literal> </entry>
-       </row>
-
-       <row>
-       <entry> <literal>+?</literal> </entry>
-       <entry> non-greedy version of <literal>+</literal> </entry>
-       </row>
-
-       <row>
-       <entry> <literal>??</literal> </entry>
-       <entry> non-greedy version of <literal>?</literal> </entry>
-       </row>
-
-       <row>
-       <entry> <literal>{</literal><replaceable>m</replaceable><literal>}?</literal> </entry>
-       <entry> non-greedy version of <literal>{</literal><replaceable>m</replaceable><literal>}</literal> </entry>
-       </row>
-
-       <row>
-       <entry> <literal>{</literal><replaceable>m</replaceable><literal>,}?</literal> </entry>
-       <entry> non-greedy version of <literal>{</literal><replaceable>m</replaceable><literal>,}</literal> </entry>
-       </row>
-
-       <row>
-       <entry>
-       <literal>{</literal><replaceable>m</replaceable><literal>,</literal><replaceable>n</replaceable><literal>}?</literal> </entry>
-       <entry> non-greedy version of <literal>{</literal><replaceable>m</replaceable><literal>,</literal><replaceable>n</replaceable><literal>}</literal> </entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-   <para>
-    The forms using <literal>{</literal><replaceable>...</replaceable><literal>}</literal>
-    are known as <firstterm>bounds</firstterm>.
-    The numbers <replaceable>m</replaceable> and <replaceable>n</replaceable> within a bound are
-    unsigned decimal integers with permissible values from 0 to 255 inclusive.
-   </para>
-
-    <para>
-     <firstterm>Non-greedy</firstterm> quantifiers (available in AREs only) match the
-     same possibilities as their corresponding normal (<firstterm>greedy</firstterm>)
-     counterparts, but prefer the smallest number rather than the largest
-     number of matches.
-     See <xref linkend="posix-matching-rules"/> for more detail.
-   </para>
-
-   <note>
-    <para>
-     A quantifier cannot immediately follow another quantifier, e.g.,
-     <literal>**</literal> is invalid.
-     A quantifier cannot
-     begin an expression or subexpression or follow
-     <literal>^</literal> or <literal>|</literal>.
-    </para>
-   </note>
-
-   <table id="posix-constraints-table">
-    <title>Regular Expression Constraints</title>
-
-    <tgroup cols="2">
-     <thead>
-      <row>
-       <entry>Constraint</entry>
-       <entry>Description</entry>
-      </row>
-     </thead>
-
-      <tbody>
-       <row>
-       <entry> <literal>^</literal> </entry>
-       <entry> matches at the beginning of the string </entry>
-       </row>
-
-       <row>
-       <entry> <literal>$</literal> </entry>
-       <entry> matches at the end of the string </entry>
-       </row>
-
-       <row>
-       <entry> <literal>(?=</literal><replaceable>re</replaceable><literal>)</literal> </entry>
-       <entry> <firstterm>positive lookahead</firstterm> matches at any point
-       where a substring matching <replaceable>re</replaceable> begins
-       (AREs only) </entry>
-       </row>
-
-       <row>
-       <entry> <literal>(?!</literal><replaceable>re</replaceable><literal>)</literal> </entry>
-       <entry> <firstterm>negative lookahead</firstterm> matches at any point
-       where no substring matching <replaceable>re</replaceable> begins
-       (AREs only) </entry>
-       </row>
-
-       <row>
-       <entry> <literal>(?&lt;=</literal><replaceable>re</replaceable><literal>)</literal> </entry>
-       <entry> <firstterm>positive lookbehind</firstterm> matches at any point
-       where a substring matching <replaceable>re</replaceable> ends
-       (AREs only) </entry>
-       </row>
-
-       <row>
-       <entry> <literal>(?&lt;!</literal><replaceable>re</replaceable><literal>)</literal> </entry>
-       <entry> <firstterm>negative lookbehind</firstterm> matches at any point
-       where no substring matching <replaceable>re</replaceable> ends
-       (AREs only) </entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-   <para>
-    Lookahead and lookbehind constraints cannot contain <firstterm>back
-    references</firstterm> (see <xref linkend="posix-escape-sequences"/>),
-    and all parentheses within them are considered non-capturing.
-   </para>
-   </sect3>
-
-   <sect3 id="posix-bracket-expressions">
-    <title>Bracket Expressions</title>
-
-   <para>
-    A <firstterm>bracket expression</firstterm> is a list of
-    characters enclosed in <literal>[]</literal>.  It normally matches
-    any single character from the list (but see below).  If the list
-    begins with <literal>^</literal>, it matches any single character
-    <emphasis>not</emphasis> from the rest of the list.
-    If two characters
-    in the list are separated by <literal>-</literal>, this is
-    shorthand for the full range of characters between those two
-    (inclusive) in the collating sequence,
-    e.g., <literal>[0-9]</literal> in <acronym>ASCII</acronym> matches
-    any decimal digit.  It is illegal for two ranges to share an
-    endpoint, e.g.,  <literal>a-c-e</literal>.  Ranges are very
-    collating-sequence-dependent, so portable programs should avoid
-    relying on them.
-   </para>
-
-   <para>
-    To include a literal <literal>]</literal> in the list, make it the
-    first character (after <literal>^</literal>, if that is used).  To
-    include a literal <literal>-</literal>, make it the first or last
-    character, or the second endpoint of a range.  To use a literal
-    <literal>-</literal> as the first endpoint of a range, enclose it
-    in <literal>[.</literal> and <literal>.]</literal> to make it a
-    collating element (see below).  With the exception of these characters,
-    some combinations using <literal>[</literal>
-    (see next paragraphs), and escapes (AREs only), all other special
-    characters lose their special significance within a bracket expression.
-    In particular, <literal>\</literal> is not special when following
-    ERE or BRE rules, though it is special (as introducing an escape)
-    in AREs.
-   </para>
-
-   <para>
-    Within a bracket expression, a collating element (a character, a
-    multiple-character sequence that collates as if it were a single
-    character, or a collating-sequence name for either) enclosed in
-    <literal>[.</literal> and <literal>.]</literal> stands for the
-    sequence of characters of that collating element.  The sequence is
-    treated as a single element of the bracket expression's list.  This
-    allows a bracket
-    expression containing a multiple-character collating element to
-    match more than one character, e.g., if the collating sequence
-    includes a <literal>ch</literal> collating element, then the RE
-    <literal>[[.ch.]]*c</literal> matches the first five characters of
-    <literal>chchcc</literal>.
-   </para>
-
-   <note>
-    <para>
-     <productname>PostgreSQL</productname> currently does not support multi-character collating
-     elements. This information describes possible future behavior.
-    </para>
-   </note>
-
-   <para>
-    Within a bracket expression, a collating element enclosed in
-    <literal>[=</literal> and <literal>=]</literal> is an <firstterm>equivalence
-    class</firstterm>, standing for the sequences of characters of all collating
-    elements equivalent to that one, including itself.  (If there are
-    no other equivalent collating elements, the treatment is as if the
-    enclosing delimiters were <literal>[.</literal> and
-    <literal>.]</literal>.)  For example, if <literal>o</literal> and
-    <literal>^</literal> are the members of an equivalence class, then
-    <literal>[[=o=]]</literal>, <literal>[[=^=]]</literal>, and
-    <literal>[o^]</literal> are all synonymous.  An equivalence class
-    cannot be an endpoint of a range.
-   </para>
-
-   <para>
-    Within a bracket expression, the name of a character class
-    enclosed in <literal>[:</literal> and <literal>:]</literal> stands
-    for the list of all characters belonging to that class.  A character
-    class cannot be used as an endpoint of a range.
-    The <acronym>POSIX</acronym> standard defines these character class
-    names:
-    <literal>alnum</literal> (letters and numeric digits),
-    <literal>alpha</literal> (letters),
-    <literal>blank</literal> (space and tab),
-    <literal>cntrl</literal> (control characters),
-    <literal>digit</literal> (numeric digits),
-    <literal>graph</literal> (printable characters except space),
-    <literal>lower</literal> (lower-case letters),
-    <literal>print</literal> (printable characters including space),
-    <literal>punct</literal> (punctuation),
-    <literal>space</literal> (any white space),
-    <literal>upper</literal> (upper-case letters),
-    and <literal>xdigit</literal> (hexadecimal digits).
-    The behavior of these standard character classes is generally
-    consistent across platforms for characters in the 7-bit ASCII set.
-    Whether a given non-ASCII character is considered to belong to one
-    of these classes depends on the <firstterm>collation</firstterm>
-    that is used for the regular-expression function or operator
-    (see <xref linkend="collation"/>), or by default on the
-    database's <envar>LC_CTYPE</envar> locale setting (see
-    <xref linkend="locale"/>).  The classification of non-ASCII
-    characters can vary across platforms even in similarly-named
-    locales.  (But the <literal>C</literal> locale never considers any
-    non-ASCII characters to belong to any of these classes.)
-    In addition to these standard character
-    classes, <productname>PostgreSQL</productname> defines
-    the <literal>word</literal> character class, which is the same as
-    <literal>alnum</literal> plus the underscore (<literal>_</literal>)
-    character, and
-    the <literal>ascii</literal> character class, which contains exactly
-    the 7-bit ASCII set.
-   </para>
-
-   <para>
-    There are two special cases of bracket expressions:  the bracket
-    expressions <literal>[[:&lt;:]]</literal> and
-    <literal>[[:&gt;:]]</literal> are constraints,
-    matching empty strings at the beginning
-    and end of a word respectively.  A word is defined as a sequence
-    of word characters that is neither preceded nor followed by word
-    characters.  A word character is any character belonging to the
-    <literal>word</literal> character class, that is, any letter, digit,
-    or underscore.  This is an extension, compatible with but not
-    specified by <acronym>POSIX</acronym> 1003.2, and should be used with
-    caution in software intended to be portable to other systems.
-    The constraint escapes described below are usually preferable; they
-    are no more standard, but are easier to type.
-   </para>
-   </sect3>
-
-   <sect3 id="posix-escape-sequences">
-    <title>Regular Expression Escapes</title>
-
-   <para>
-    <firstterm>Escapes</firstterm> are special sequences beginning with <literal>\</literal>
-    followed by an alphanumeric character. Escapes come in several varieties:
-    character entry, class shorthands, constraint escapes, and back references.
-    A <literal>\</literal> followed by an alphanumeric character but not constituting
-    a valid escape is illegal in AREs.
-    In EREs, there are no escapes: outside a bracket expression,
-    a <literal>\</literal> followed by an alphanumeric character merely stands for
-    that character as an ordinary character, and inside a bracket expression,
-    <literal>\</literal> is an ordinary character.
-    (The latter is the one actual incompatibility between EREs and AREs.)
-   </para>
-
-   <para>
-    <firstterm>Character-entry escapes</firstterm> exist to make it easier to specify
-    non-printing and other inconvenient characters in REs.  They are
-    shown in <xref linkend="posix-character-entry-escapes-table"/>.
-   </para>
-
-   <para>
-    <firstterm>Class-shorthand escapes</firstterm> provide shorthands for certain
-    commonly-used character classes.  They are
-    shown in <xref linkend="posix-class-shorthand-escapes-table"/>.
-   </para>
-
-   <para>
-    A <firstterm>constraint escape</firstterm> is a constraint,
-    matching the empty string if specific conditions are met,
-    written as an escape.  They are
-    shown in <xref linkend="posix-constraint-escapes-table"/>.
-   </para>
-
-   <para>
-    A <firstterm>back reference</firstterm> (<literal>\</literal><replaceable>n</replaceable>) matches the
-    same string matched by the previous parenthesized subexpression specified
-    by the number <replaceable>n</replaceable>
-    (see <xref linkend="posix-constraint-backref-table"/>).  For example,
-    <literal>([bc])\1</literal> matches <literal>bb</literal> or <literal>cc</literal>
-    but not <literal>bc</literal> or <literal>cb</literal>.
-    The subexpression must entirely precede the back reference in the RE.
-    Subexpressions are numbered in the order of their leading parentheses.
-    Non-capturing parentheses do not define subexpressions.
-    The back reference considers only the string characters matched by the
-    referenced subexpression, not any constraints contained in it.  For
-    example, <literal>(^\d)\1</literal> will match <literal>22</literal>.
-   </para>
-
-   <table id="posix-character-entry-escapes-table">
-    <title>Regular Expression Character-Entry Escapes</title>
-
-    <tgroup cols="2">
-     <thead>
-      <row>
-       <entry>Escape</entry>
-       <entry>Description</entry>
-      </row>
-     </thead>
-
-      <tbody>
-       <row>
-       <entry> <literal>\a</literal> </entry>
-       <entry> alert (bell) character, as in C </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\b</literal> </entry>
-       <entry> backspace, as in C </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\B</literal> </entry>
-       <entry> synonym for backslash (<literal>\</literal>) to help reduce the need for backslash
-       doubling </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\c</literal><replaceable>X</replaceable> </entry>
-       <entry> (where <replaceable>X</replaceable> is any character) the character whose
-       low-order 5 bits are the same as those of
-       <replaceable>X</replaceable>, and whose other bits are all zero </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\e</literal> </entry>
-       <entry> the character whose collating-sequence name
-       is <literal>ESC</literal>,
-       or failing that, the character with octal value <literal>033</literal> </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\f</literal> </entry>
-       <entry> form feed, as in C </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\n</literal> </entry>
-       <entry> newline, as in C </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\r</literal> </entry>
-       <entry> carriage return, as in C </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\t</literal> </entry>
-       <entry> horizontal tab, as in C </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\u</literal><replaceable>wxyz</replaceable> </entry>
-       <entry> (where <replaceable>wxyz</replaceable> is exactly four hexadecimal digits)
-       the character whose hexadecimal value is
-       <literal>0x</literal><replaceable>wxyz</replaceable>
-       </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\U</literal><replaceable>stuvwxyz</replaceable> </entry>
-       <entry> (where <replaceable>stuvwxyz</replaceable> is exactly eight hexadecimal
-       digits)
-       the character whose hexadecimal value is
-       <literal>0x</literal><replaceable>stuvwxyz</replaceable>
-       </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\v</literal> </entry>
-       <entry> vertical tab, as in C </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\x</literal><replaceable>hhh</replaceable> </entry>
-       <entry> (where <replaceable>hhh</replaceable> is any sequence of hexadecimal
-       digits)
-       the character whose hexadecimal value is
-       <literal>0x</literal><replaceable>hhh</replaceable>
-       (a single character no matter how many hexadecimal digits are used)
-       </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\0</literal> </entry>
-       <entry> the character whose value is <literal>0</literal> (the null byte)</entry>
-       </row>
-
-       <row>
-       <entry> <literal>\</literal><replaceable>xy</replaceable> </entry>
-       <entry> (where <replaceable>xy</replaceable> is exactly two octal digits,
-       and is not a <firstterm>back reference</firstterm>)
-       the character whose octal value is
-       <literal>0</literal><replaceable>xy</replaceable> </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\</literal><replaceable>xyz</replaceable> </entry>
-       <entry> (where <replaceable>xyz</replaceable> is exactly three octal digits,
-       and is not a <firstterm>back reference</firstterm>)
-       the character whose octal value is
-       <literal>0</literal><replaceable>xyz</replaceable> </entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-   <para>
-    Hexadecimal digits are <literal>0</literal>-<literal>9</literal>,
-    <literal>a</literal>-<literal>f</literal>, and <literal>A</literal>-<literal>F</literal>.
-    Octal digits are <literal>0</literal>-<literal>7</literal>.
-   </para>
-
-   <para>
-    Numeric character-entry escapes specifying values outside the ASCII range
-    (0&ndash;127) have meanings dependent on the database encoding.  When the
-    encoding is UTF-8, escape values are equivalent to Unicode code points,
-    for example <literal>\u1234</literal> means the character <literal>U+1234</literal>.
-    For other multibyte encodings, character-entry escapes usually just
-    specify the concatenation of the byte values for the character.  If the
-    escape value does not correspond to any legal character in the database
-    encoding, no error will be raised, but it will never match any data.
-   </para>
-
-   <para>
-    The character-entry escapes are always taken as ordinary characters.
-    For example, <literal>\135</literal> is <literal>]</literal> in ASCII, but
-    <literal>\135</literal> does not terminate a bracket expression.
-   </para>
-
-   <table id="posix-class-shorthand-escapes-table">
-    <title>Regular Expression Class-Shorthand Escapes</title>
-
-    <tgroup cols="2">
-     <thead>
-      <row>
-       <entry>Escape</entry>
-       <entry>Description</entry>
-      </row>
-     </thead>
-
-      <tbody>
-       <row>
-       <entry> <literal>\d</literal> </entry>
-       <entry> matches any digit, like
-        <literal>[[:digit:]]</literal> </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\s</literal> </entry>
-       <entry> matches any whitespace character, like
-        <literal>[[:space:]]</literal> </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\w</literal> </entry>
-       <entry> matches any word character, like
-        <literal>[[:word:]]</literal> </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\D</literal> </entry>
-       <entry> matches any non-digit, like
-        <literal>[^[:digit:]]</literal> </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\S</literal> </entry>
-       <entry> matches any non-whitespace character, like
-        <literal>[^[:space:]]</literal> </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\W</literal> </entry>
-       <entry> matches any non-word character, like
-        <literal>[^[:word:]]</literal> </entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-   <para>
-    The class-shorthand escapes also work within bracket expressions,
-    although the definitions shown above are not quite syntactically
-    valid in that context.
-    For example, <literal>[a-c\d]</literal> is equivalent to
-    <literal>[a-c[:digit:]]</literal>.
-   </para>
-
-   <table id="posix-constraint-escapes-table">
-    <title>Regular Expression Constraint Escapes</title>
-
-    <tgroup cols="2">
-     <thead>
-      <row>
-       <entry>Escape</entry>
-       <entry>Description</entry>
-      </row>
-     </thead>
-
-      <tbody>
-       <row>
-       <entry> <literal>\A</literal> </entry>
-       <entry> matches only at the beginning of the string
-       (see <xref linkend="posix-matching-rules"/> for how this differs from
-       <literal>^</literal>) </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\m</literal> </entry>
-       <entry> matches only at the beginning of a word </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\M</literal> </entry>
-       <entry> matches only at the end of a word </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\y</literal> </entry>
-       <entry> matches only at the beginning or end of a word </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\Y</literal> </entry>
-       <entry> matches only at a point that is not the beginning or end of a
-       word </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\Z</literal> </entry>
-       <entry> matches only at the end of the string
-       (see <xref linkend="posix-matching-rules"/> for how this differs from
-       <literal>$</literal>) </entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-   <para>
-    A word is defined as in the specification of
-    <literal>[[:&lt;:]]</literal> and <literal>[[:&gt;:]]</literal> above.
-    Constraint escapes are illegal within bracket expressions.
-   </para>
-
-   <table id="posix-constraint-backref-table">
-    <title>Regular Expression Back References</title>
-
-    <tgroup cols="2">
-     <thead>
-      <row>
-       <entry>Escape</entry>
-       <entry>Description</entry>
-      </row>
-     </thead>
-
-      <tbody>
-       <row>
-       <entry> <literal>\</literal><replaceable>m</replaceable> </entry>
-       <entry> (where <replaceable>m</replaceable> is a nonzero digit)
-       a back reference to the <replaceable>m</replaceable>'th subexpression </entry>
-       </row>
-
-       <row>
-       <entry> <literal>\</literal><replaceable>mnn</replaceable> </entry>
-       <entry> (where <replaceable>m</replaceable> is a nonzero digit, and
-       <replaceable>nn</replaceable> is some more digits, and the decimal value
-       <replaceable>mnn</replaceable> is not greater than the number of closing capturing
-       parentheses seen so far)
-       a back reference to the <replaceable>mnn</replaceable>'th subexpression </entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-   <note>
-    <para>
-     There is an inherent ambiguity between octal character-entry
-     escapes and back references, which is resolved by the following heuristics,
-     as hinted at above.
-     A leading zero always indicates an octal escape.
-     A single non-zero digit, not followed by another digit,
-     is always taken as a back reference.
-     A multi-digit sequence not starting with a zero is taken as a back
-     reference if it comes after a suitable subexpression
-     (i.e., the number is in the legal range for a back reference),
-     and otherwise is taken as octal.
-    </para>
-   </note>
-   </sect3>
-
-   <sect3 id="posix-metasyntax">
-    <title>Regular Expression Metasyntax</title>
-
-   <para>
-    In addition to the main syntax described above, there are some special
-    forms and miscellaneous syntactic facilities available.
-   </para>
-
-   <para>
-    An RE can begin with one of two special <firstterm>director</firstterm> prefixes.
-    If an RE begins with <literal>***:</literal>,
-    the rest of the RE is taken as an ARE.  (This normally has no effect in
-    <productname>PostgreSQL</productname>, since REs are assumed to be AREs;
-    but it does have an effect if ERE or BRE mode had been specified by
-    the <replaceable>flags</replaceable> parameter to a regex function.)
-    If an RE begins with <literal>***=</literal>,
-    the rest of the RE is taken to be a literal string,
-    with all characters considered ordinary characters.
-   </para>
-
-   <para>
-    An ARE can begin with <firstterm>embedded options</firstterm>:
-    a sequence <literal>(?</literal><replaceable>xyz</replaceable><literal>)</literal>
-    (where <replaceable>xyz</replaceable> is one or more alphabetic characters)
-    specifies options affecting the rest of the RE.
-    These options override any previously determined options &mdash;
-    in particular, they can override the case-sensitivity behavior implied by
-    a regex operator, or the <replaceable>flags</replaceable> parameter to a regex
-    function.
-    The available option letters are
-    shown in <xref linkend="posix-embedded-options-table"/>.
-    Note that these same option letters are used in the <replaceable>flags</replaceable>
-    parameters of regex functions.
-   </para>
-
-   <table id="posix-embedded-options-table">
-    <title>ARE Embedded-Option Letters</title>
-
-    <tgroup cols="2">
-     <thead>
-      <row>
-       <entry>Option</entry>
-       <entry>Description</entry>
-      </row>
-     </thead>
-
-      <tbody>
-       <row>
-       <entry> <literal>b</literal> </entry>
-       <entry> rest of RE is a BRE </entry>
-       </row>
-
-       <row>
-       <entry> <literal>c</literal> </entry>
-       <entry> case-sensitive matching (overrides operator type) </entry>
-       </row>
-
-       <row>
-       <entry> <literal>e</literal> </entry>
-       <entry> rest of RE is an ERE </entry>
-       </row>
-
-       <row>
-       <entry> <literal>i</literal> </entry>
-       <entry> case-insensitive matching (see
-       <xref linkend="posix-matching-rules"/>) (overrides operator type) </entry>
-       </row>
-
-       <row>
-       <entry> <literal>m</literal> </entry>
-       <entry> historical synonym for <literal>n</literal> </entry>
-       </row>
-
-       <row>
-       <entry> <literal>n</literal> </entry>
-       <entry> newline-sensitive matching (see
-       <xref linkend="posix-matching-rules"/>) </entry>
-       </row>
-
-       <row>
-       <entry> <literal>p</literal> </entry>
-       <entry> partial newline-sensitive matching (see
-       <xref linkend="posix-matching-rules"/>) </entry>
-       </row>
-
-       <row>
-       <entry> <literal>q</literal> </entry>
-       <entry> rest of RE is a literal (<quote>quoted</quote>) string, all ordinary
-       characters </entry>
-       </row>
-
-       <row>
-       <entry> <literal>s</literal> </entry>
-       <entry> non-newline-sensitive matching (default) </entry>
-       </row>
-
-       <row>
-       <entry> <literal>t</literal> </entry>
-       <entry> tight syntax (default; see below) </entry>
-       </row>
-
-       <row>
-       <entry> <literal>w</literal> </entry>
-       <entry> inverse partial newline-sensitive (<quote>weird</quote>) matching
-       (see <xref linkend="posix-matching-rules"/>) </entry>
-       </row>
-
-       <row>
-       <entry> <literal>x</literal> </entry>
-       <entry> expanded syntax (see below) </entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-   <para>
-    Embedded options take effect at the <literal>)</literal> terminating the sequence.
-    They can appear only at the start of an ARE (after the
-    <literal>***:</literal> director if any).
-   </para>
-
-   <para>
-    In addition to the usual (<firstterm>tight</firstterm>) RE syntax, in which all
-    characters are significant, there is an <firstterm>expanded</firstterm> syntax,
-    available by specifying the embedded <literal>x</literal> option.
-    In the expanded syntax,
-    white-space characters in the RE are ignored, as are
-    all characters between a <literal>#</literal>
-    and the following newline (or the end of the RE).  This
-    permits paragraphing and commenting a complex RE.
-    There are three exceptions to that basic rule:
-
-    <itemizedlist>
-     <listitem>
-      <para>
-       a white-space character or <literal>#</literal> preceded by <literal>\</literal> is
-       retained
-      </para>
-     </listitem>
-     <listitem>
-      <para>
-       white space or <literal>#</literal> within a bracket expression is retained
-      </para>
-     </listitem>
-     <listitem>
-      <para>
-       white space and comments cannot appear within multi-character symbols,
-       such as <literal>(?:</literal>
-      </para>
-     </listitem>
-    </itemizedlist>
-
-    For this purpose, white-space characters are blank, tab, newline, and
-    any character that belongs to the <replaceable>space</replaceable> character class.
-   </para>
-
-   <para>
-    Finally, in an ARE, outside bracket expressions, the sequence
-    <literal>(?#</literal><replaceable>ttt</replaceable><literal>)</literal>
-    (where <replaceable>ttt</replaceable> is any text not containing a <literal>)</literal>)
-    is a comment, completely ignored.
-    Again, this is not allowed between the characters of
-    multi-character symbols, like <literal>(?:</literal>.
-    Such comments are more a historical artifact than a useful facility,
-    and their use is deprecated; use the expanded syntax instead.
-   </para>
-
-   <para>
-    <emphasis>None</emphasis> of these metasyntax extensions is available if
-    an initial <literal>***=</literal> director
-    has specified that the user's input be treated as a literal string
-    rather than as an RE.
-   </para>
-   </sect3>
-
-   <sect3 id="posix-matching-rules">
-    <title>Regular Expression Matching Rules</title>
-
-   <para>
-    In the event that an RE could match more than one substring of a given
-    string, the RE matches the one starting earliest in the string.
-    If the RE could match more than one substring starting at that point,
-    either the longest possible match or the shortest possible match will
-    be taken, depending on whether the RE is <firstterm>greedy</firstterm> or
-    <firstterm>non-greedy</firstterm>.
-   </para>
-
-   <para>
-    Whether an RE is greedy or not is determined by the following rules:
-    <itemizedlist>
-     <listitem>
-      <para>
-       Most atoms, and all constraints, have no greediness attribute (because
-       they cannot match variable amounts of text anyway).
-      </para>
-     </listitem>
-     <listitem>
-      <para>
-       Adding parentheses around an RE does not change its greediness.
-      </para>
-     </listitem>
-     <listitem>
-      <para>
-       A quantified atom with a fixed-repetition quantifier
-       (<literal>{</literal><replaceable>m</replaceable><literal>}</literal>
-       or
-       <literal>{</literal><replaceable>m</replaceable><literal>}?</literal>)
-       has the same greediness (possibly none) as the atom itself.
-      </para>
-     </listitem>
-     <listitem>
-      <para>
-       A quantified atom with other normal quantifiers (including
-       <literal>{</literal><replaceable>m</replaceable><literal>,</literal><replaceable>n</replaceable><literal>}</literal>
-       with <replaceable>m</replaceable> equal to <replaceable>n</replaceable>)
-       is greedy (prefers longest match).
-      </para>
-     </listitem>
-     <listitem>
-      <para>
-       A quantified atom with a non-greedy quantifier (including
-       <literal>{</literal><replaceable>m</replaceable><literal>,</literal><replaceable>n</replaceable><literal>}?</literal>
-       with <replaceable>m</replaceable> equal to <replaceable>n</replaceable>)
-       is non-greedy (prefers shortest match).
-      </para>
-     </listitem>
-     <listitem>
-      <para>
-       A branch &mdash; that is, an RE that has no top-level
-       <literal>|</literal> operator &mdash; has the same greediness as the first
-       quantified atom in it that has a greediness attribute.
-      </para>
-     </listitem>
-     <listitem>
-      <para>
-       An RE consisting of two or more branches connected by the
-       <literal>|</literal> operator is always greedy.
-      </para>
-     </listitem>
-    </itemizedlist>
-   </para>
-
-   <para>
-    The above rules associate greediness attributes not only with individual
-    quantified atoms, but with branches and entire REs that contain quantified
-    atoms.  What that means is that the matching is done in such a way that
-    the branch, or whole RE, matches the longest or shortest possible
-    substring <emphasis>as a whole</emphasis>.  Once the length of the entire match
-    is determined, the part of it that matches any particular subexpression
-    is determined on the basis of the greediness attribute of that
-    subexpression, with subexpressions starting earlier in the RE taking
-    priority over ones starting later.
-   </para>
-
-   <para>
-    An example of what this means:
-<screen>
-SELECT SUBSTRING('XY1234Z', 'Y*([0-9]{1,3})');
-<lineannotation>Result: </lineannotation><computeroutput>123</computeroutput>
-SELECT SUBSTRING('XY1234Z', 'Y*?([0-9]{1,3})');
-<lineannotation>Result: </lineannotation><computeroutput>1</computeroutput>
-</screen>
-    In the first case, the RE as a whole is greedy because <literal>Y*</literal>
-    is greedy.  It can match beginning at the <literal>Y</literal>, and it matches
-    the longest possible string starting there, i.e., <literal>Y123</literal>.
-    The output is the parenthesized part of that, or <literal>123</literal>.
-    In the second case, the RE as a whole is non-greedy because <literal>Y*?</literal>
-    is non-greedy.  It can match beginning at the <literal>Y</literal>, and it matches
-    the shortest possible string starting there, i.e., <literal>Y1</literal>.
-    The subexpression <literal>[0-9]{1,3}</literal> is greedy but it cannot change
-    the decision as to the overall match length; so it is forced to match
-    just <literal>1</literal>.
-   </para>
-
-   <para>
-    In short, when an RE contains both greedy and non-greedy subexpressions,
-    the total match length is either as long as possible or as short as
-    possible, according to the attribute assigned to the whole RE.  The
-    attributes assigned to the subexpressions only affect how much of that
-    match they are allowed to <quote>eat</quote> relative to each other.
-   </para>
-
-   <para>
-    The quantifiers <literal>{1,1}</literal> and <literal>{1,1}?</literal>
-    can be used to force greediness or non-greediness, respectively,
-    on a subexpression or a whole RE.
-    This is useful when you need the whole RE to have a greediness attribute
-    different from what's deduced from its elements.  As an example,
-    suppose that we are trying to separate a string containing some digits
-    into the digits and the parts before and after them.  We might try to
-    do that like this:
-<screen>
-SELECT regexp_match('abc01234xyz', '(.*)(\d+)(.*)');
-<lineannotation>Result: </lineannotation><computeroutput>{abc0123,4,xyz}</computeroutput>
-</screen>
-    That didn't work: the first <literal>.*</literal> is greedy so
-    it <quote>eats</quote> as much as it can, leaving the <literal>\d+</literal> to
-    match at the last possible place, the last digit.  We might try to fix
-    that by making it non-greedy:
-<screen>
-SELECT regexp_match('abc01234xyz', '(.*?)(\d+)(.*)');
-<lineannotation>Result: </lineannotation><computeroutput>{abc,0,""}</computeroutput>
-</screen>
-    That didn't work either, because now the RE as a whole is non-greedy
-    and so it ends the overall match as soon as possible.  We can get what
-    we want by forcing the RE as a whole to be greedy:
-<screen>
-SELECT regexp_match('abc01234xyz', '(?:(.*?)(\d+)(.*)){1,1}');
-<lineannotation>Result: </lineannotation><computeroutput>{abc,01234,xyz}</computeroutput>
-</screen>
-    Controlling the RE's overall greediness separately from its components'
-    greediness allows great flexibility in handling variable-length patterns.
-   </para>
-
-   <para>
-    When deciding what is a longer or shorter match,
-    match lengths are measured in characters, not collating elements.
-    An empty string is considered longer than no match at all.
-    For example:
-    <literal>bb*</literal>
-    matches the three middle characters of <literal>abbbc</literal>;
-    <literal>(week|wee)(night|knights)</literal>
-    matches all ten characters of <literal>weeknights</literal>;
-    when <literal>(.*).*</literal>
-    is matched against <literal>abc</literal> the parenthesized subexpression
-    matches all three characters; and when
-    <literal>(a*)*</literal> is matched against <literal>bc</literal>
-    both the whole RE and the parenthesized
-    subexpression match an empty string.
-   </para>
-
-   <para>
-    If case-independent matching is specified,
-    the effect is much as if all case distinctions had vanished from the
-    alphabet.
-    When an alphabetic that exists in multiple cases appears as an
-    ordinary character outside a bracket expression, it is effectively
-    transformed into a bracket expression containing both cases,
-    e.g., <literal>x</literal> becomes <literal>[xX]</literal>.
-    When it appears inside a bracket expression, all case counterparts
-    of it are added to the bracket expression, e.g.,
-    <literal>[x]</literal> becomes <literal>[xX]</literal>
-    and <literal>[^x]</literal> becomes <literal>[^xX]</literal>.
-   </para>
-
-   <para>
-    If newline-sensitive matching is specified, <literal>.</literal>
-    and bracket expressions using <literal>^</literal>
-    will never match the newline character
-    (so that matches will not cross lines unless the RE
-    explicitly includes a newline)
-    and <literal>^</literal> and <literal>$</literal>
-    will match the empty string after and before a newline
-    respectively, in addition to matching at beginning and end of string
-    respectively.
-    But the ARE escapes <literal>\A</literal> and <literal>\Z</literal>
-    continue to match beginning or end of string <emphasis>only</emphasis>.
-    Also, the character class shorthands <literal>\D</literal>
-    and <literal>\W</literal> will match a newline regardless of this mode.
-    (Before <productname>PostgreSQL</productname> 14, they did not match
-    newlines when in newline-sensitive mode.
-    Write <literal>[^[:digit:]]</literal>
-    or <literal>[^[:word:]]</literal> to get the old behavior.)
-   </para>
-
-   <para>
-    If partial newline-sensitive matching is specified,
-    this affects <literal>.</literal> and bracket expressions
-    as with newline-sensitive matching, but not <literal>^</literal>
-    and <literal>$</literal>.
-   </para>
-
-   <para>
-    If inverse partial newline-sensitive matching is specified,
-    this affects <literal>^</literal> and <literal>$</literal>
-    as with newline-sensitive matching, but not <literal>.</literal>
-    and bracket expressions.
-    This isn't very useful but is provided for symmetry.
-   </para>
-   </sect3>
-
-   <sect3 id="posix-limits-compatibility">
-    <title>Limits and Compatibility</title>
-
-   <para>
-    No particular limit is imposed on the length of REs in this
-    implementation.  However,
-    programs intended to be highly portable should not employ REs longer
-    than 256 bytes,
-    as a POSIX-compliant implementation can refuse to accept such REs.
-   </para>
-
-   <para>
-    The only feature of AREs that is actually incompatible with
-    POSIX EREs is that <literal>\</literal> does not lose its special
-    significance inside bracket expressions.
-    All other ARE features use syntax which is illegal or has
-    undefined or unspecified effects in POSIX EREs;
-    the <literal>***</literal> syntax of directors likewise is outside the POSIX
-    syntax for both BREs and EREs.
-   </para>
-
-   <para>
-    Many of the ARE extensions are borrowed from Perl, but some have
-    been changed to clean them up, and a few Perl extensions are not present.
-    Incompatibilities of note include <literal>\b</literal>, <literal>\B</literal>,
-    the lack of special treatment for a trailing newline,
-    the addition of complemented bracket expressions to the things
-    affected by newline-sensitive matching,
-    the restrictions on parentheses and back references in lookahead/lookbehind
-    constraints, and the longest/shortest-match (rather than first-match)
-    matching semantics.
-   </para>
-   </sect3>
-
-   <sect3 id="posix-basic-regexes">
-    <title>Basic Regular Expressions</title>
-
-   <para>
-    BREs differ from EREs in several respects.
-    In BREs, <literal>|</literal>, <literal>+</literal>, and <literal>?</literal>
-    are ordinary characters and there is no equivalent
-    for their functionality.
-    The delimiters for bounds are
-    <literal>\{</literal> and <literal>\}</literal>,
-    with <literal>{</literal> and <literal>}</literal>
-    by themselves ordinary characters.
-    The parentheses for nested subexpressions are
-    <literal>\(</literal> and <literal>\)</literal>,
-    with <literal>(</literal> and <literal>)</literal> by themselves ordinary characters.
-    <literal>^</literal> is an ordinary character except at the beginning of the
-    RE or the beginning of a parenthesized subexpression,
-    <literal>$</literal> is an ordinary character except at the end of the
-    RE or the end of a parenthesized subexpression,
-    and <literal>*</literal> is an ordinary character if it appears at the beginning
-    of the RE or the beginning of a parenthesized subexpression
-    (after a possible leading <literal>^</literal>).
-    Finally, single-digit back references are available, and
-    <literal>\&lt;</literal> and <literal>\&gt;</literal>
-    are synonyms for
-    <literal>[[:&lt;:]]</literal> and <literal>[[:&gt;:]]</literal>
-    respectively; no other escapes are available in BREs.
-   </para>
-   </sect3>
-
-<!-- end re_syntax.n man page -->
-
-   <sect3 id="posix-vs-xquery">
-   <title>Differences from SQL Standard and XQuery</title>
-
-   <indexterm zone="posix-vs-xquery">
-    <primary>LIKE_REGEX</primary>
-   </indexterm>
-
-   <indexterm zone="posix-vs-xquery">
-    <primary>OCCURRENCES_REGEX</primary>
-   </indexterm>
-
-   <indexterm zone="posix-vs-xquery">
-    <primary>POSITION_REGEX</primary>
-   </indexterm>
-
-   <indexterm zone="posix-vs-xquery">
-    <primary>SUBSTRING_REGEX</primary>
-   </indexterm>
-
-   <indexterm zone="posix-vs-xquery">
-    <primary>TRANSLATE_REGEX</primary>
-   </indexterm>
-
-   <indexterm zone="posix-vs-xquery">
-    <primary>XQuery regular expressions</primary>
-   </indexterm>
-
-    <para>
-     Since SQL:2008, the SQL standard includes regular expression operators
-     and functions that performs pattern
-     matching according to the XQuery regular expression
-     standard:
-     <itemizedlist>
-      <listitem><para><literal>LIKE_REGEX</literal></para></listitem>
-      <listitem><para><literal>OCCURRENCES_REGEX</literal></para></listitem>
-      <listitem><para><literal>POSITION_REGEX</literal></para></listitem>
-      <listitem><para><literal>SUBSTRING_REGEX</literal></para></listitem>
-      <listitem><para><literal>TRANSLATE_REGEX</literal></para></listitem>
-     </itemizedlist>
-     <productname>PostgreSQL</productname> does not currently implement these
-     operators and functions.  You can get approximately equivalent
-     functionality in each case as shown in <xref
-     linkend="functions-regexp-sql-table"/>.  (Various optional clauses on
-     both sides have been omitted in this table.)
-    </para>
-
-    <table id="functions-regexp-sql-table">
-     <title>Regular Expression Functions Equivalencies</title>
-
-     <tgroup cols="2">
-      <thead>
-       <row>
-        <entry>SQL standard</entry>
-        <entry><productname>PostgreSQL</productname></entry>
-       </row>
-      </thead>
-
-      <tbody>
-       <row>
-        <entry><literal><replaceable>string</replaceable> LIKE_REGEX <replaceable>pattern</replaceable></literal></entry>
-        <entry><literal>regexp_like(<replaceable>string</replaceable>, <replaceable>pattern</replaceable>)</literal> or <literal><replaceable>string</replaceable> ~ <replaceable>pattern</replaceable></literal></entry>
-       </row>
-
-       <row>
-        <entry><literal>OCCURRENCES_REGEX(<replaceable>pattern</replaceable> IN <replaceable>string</replaceable>)</literal></entry>
-        <entry><literal>regexp_count(<replaceable>string</replaceable>, <replaceable>pattern</replaceable>)</literal></entry>
-       </row>
-
-       <row>
-        <entry><literal>POSITION_REGEX(<replaceable>pattern</replaceable> IN <replaceable>string</replaceable>)</literal></entry>
-        <entry><literal>regexp_instr(<replaceable>string</replaceable>, <replaceable>pattern</replaceable>)</literal></entry>
-       </row>
-
-       <row>
-        <entry><literal>SUBSTRING_REGEX(<replaceable>pattern</replaceable> IN <replaceable>string</replaceable>)</literal></entry>
-        <entry><literal>regexp_substr(<replaceable>string</replaceable>, <replaceable>pattern</replaceable>)</literal></entry>
-       </row>
-
-       <row>
-        <entry><literal>TRANSLATE_REGEX(<replaceable>pattern</replaceable> IN <replaceable>string</replaceable> WITH <replaceable>replacement</replaceable>)</literal></entry>
-        <entry><literal>regexp_replace(<replaceable>string</replaceable>, <replaceable>pattern</replaceable>, <replaceable>replacement</replaceable>)</literal></entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-    <para>
-     Regular expression functions similar to those provided by PostgreSQL are
-     also available in a number of other SQL implementations, whereas the
-     SQL-standard functions are not as widely implemented.  Some of the
-     details of the regular expression syntax will likely differ in each
-     implementation.
-    </para>
-
-    <para>
-     The SQL-standard operators and functions use XQuery regular expressions,
-     which are quite close to the ARE syntax described above.
-     Notable differences between the existing POSIX-based
-     regular-expression feature and XQuery regular expressions include:
-
-     <itemizedlist>
-      <listitem>
-       <para>
-        XQuery character class subtraction is not supported.  An example of
-        this feature is using the following to match only English
-        consonants: <literal>[a-z-[aeiou]]</literal>.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        XQuery character class shorthands <literal>\c</literal>,
-        <literal>\C</literal>, <literal>\i</literal>,
-        and <literal>\I</literal> are not supported.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        XQuery character class elements
-        using <literal>\p{UnicodeProperty}</literal> or the
-        inverse <literal>\P{UnicodeProperty}</literal> are not supported.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        POSIX interprets character classes such as <literal>\w</literal>
-        (see <xref linkend="posix-class-shorthand-escapes-table"/>)
-        according to the prevailing locale (which you can control by
-        attaching a <literal>COLLATE</literal> clause to the operator or
-        function).  XQuery specifies these classes by reference to Unicode
-        character properties, so equivalent behavior is obtained only with
-        a locale that follows the Unicode rules.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        The SQL standard (not XQuery itself) attempts to cater for more
-        variants of <quote>newline</quote> than POSIX does.  The
-        newline-sensitive matching options described above consider only
-        ASCII NL (<literal>\n</literal>) to be a newline, but SQL would have
-        us treat CR (<literal>\r</literal>), CRLF (<literal>\r\n</literal>)
-        (a Windows-style newline), and some Unicode-only characters like
-        LINE SEPARATOR (U+2028) as newlines as well.
-        Notably, <literal>.</literal> and <literal>\s</literal> should
-        count <literal>\r\n</literal> as one character not two according to
-        SQL.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        Of the character-entry escapes described in
-        <xref linkend="posix-character-entry-escapes-table"/>,
-        XQuery supports only <literal>\n</literal>, <literal>\r</literal>,
-        and <literal>\t</literal>.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        XQuery does not support
-        the <literal>[:<replaceable>name</replaceable>:]</literal> syntax
-        for character classes within bracket expressions.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        XQuery does not have lookahead or lookbehind constraints,
-        nor any of the constraint escapes described in
-        <xref linkend="posix-constraint-escapes-table"/>.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        The metasyntax forms described in <xref linkend="posix-metasyntax"/>
-        do not exist in XQuery.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        The regular expression flag letters defined by XQuery are
-        related to but not the same as the option letters for POSIX
-        (<xref linkend="posix-embedded-options-table"/>).  While the
-        <literal>i</literal> and <literal>q</literal> options behave the
-        same, others do not:
-        <itemizedlist>
-         <listitem>
-          <para>
-           XQuery's <literal>s</literal> (allow dot to match newline)
-           and <literal>m</literal> (allow <literal>^</literal>
-           and <literal>$</literal> to match at newlines) flags provide
-           access to the same behaviors as
-           POSIX's <literal>n</literal>, <literal>p</literal>
-           and <literal>w</literal> flags, but they
-           do <emphasis>not</emphasis> match the behavior of
-           POSIX's <literal>s</literal> and <literal>m</literal> flags.
-           Note in particular that dot-matches-newline is the default
-           behavior in POSIX but not XQuery.
-          </para>
-         </listitem>
-         <listitem>
-          <para>
-           XQuery's <literal>x</literal> (ignore whitespace in pattern) flag
-           is noticeably different from POSIX's expanded-mode flag.
-           POSIX's <literal>x</literal> flag also
-           allows <literal>#</literal> to begin a comment in the pattern,
-           and POSIX will not ignore a whitespace character after a
-           backslash.
-          </para>
-         </listitem>
-        </itemizedlist>
-       </para>
-      </listitem>
-     </itemizedlist>
-    </para>
-
-   </sect3>
-  </sect2>
- </sect1>
-
-
-  <sect1 id="functions-formatting">
-   <title>Data Type Formatting Functions</title>
-
-   <indexterm>
-    <primary>formatting</primary>
-   </indexterm>
-
-   <para>
-    The <productname>PostgreSQL</productname> formatting functions
-    provide a powerful set of tools for converting various data types
-    (date/time, integer, floating point, numeric) to formatted strings
-    and for converting from formatted strings to specific data types.
-    <xref linkend="functions-formatting-table"/> lists them.
-    These functions all follow a common calling convention: the first
-    argument is the value to be formatted and the second argument is a
-    template that defines the output or input format.
-   </para>
-
-   <table id="functions-formatting-table">
-    <title>Formatting Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_char</primary>
-        </indexterm>
-        <function>to_char</function> ( <type>timestamp</type>, <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>to_char</function> ( <type>timestamp with time zone</type>, <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts time stamp to string according to the given format.
-       </para>
-       <para>
-        <literal>to_char(timestamp '2002-04-20 17:31:12.66', 'HH12:MI:SS')</literal>
-        <returnvalue>05:31:12</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>to_char</function> ( <type>interval</type>, <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts interval to string according to the given format.
-       </para>
-       <para>
-       <literal>to_char(interval '15h 2m 12s', 'HH24:MI:SS')</literal>
-       <returnvalue>15:02:12</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>to_char</function> ( <replaceable>numeric_type</replaceable>, <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts number to string according to the given format; available
-        for <type>integer</type>, <type>bigint</type>, <type>numeric</type>,
-        <type>real</type>, <type>double precision</type>.
-       </para>
-       <para>
-        <literal>to_char(125, '999')</literal>
-        <returnvalue>125</returnvalue>
-       </para>
-       <para>
-        <literal>to_char(125.8::real, '999D9')</literal>
-        <returnvalue>125.8</returnvalue>
-       </para>
-       <para>
-        <literal>to_char(-125.8, '999D99S')</literal>
-        <returnvalue>125.80-</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_date</primary>
-        </indexterm>
-        <function>to_date</function> ( <type>text</type>, <type>text</type> )
-        <returnvalue>date</returnvalue>
-       </para>
-       <para>
-        Converts string to date according to the given format.
-       </para>
-       <para>
-        <literal>to_date('05 Dec 2000', 'DD Mon YYYY')</literal>
-        <returnvalue>2000-12-05</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_number</primary>
-        </indexterm>
-        <function>to_number</function> ( <type>text</type>, <type>text</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para>
-        Converts string to numeric according to the given format.
-       </para>
-       <para>
-        <literal>to_number('12,454.8-', '99G999D9S')</literal>
-        <returnvalue>-12454.8</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_timestamp</primary>
-        </indexterm>
-        <function>to_timestamp</function> ( <type>text</type>, <type>text</type> )
-        <returnvalue>timestamp with time zone</returnvalue>
-       </para>
-       <para>
-        Converts string to time stamp according to the given format.
-        (See also <function>to_timestamp(double precision)</function> in
-        <xref linkend="functions-datetime-table"/>.)
-       </para>
-       <para>
-        <literal>to_timestamp('05 Dec 2000', 'DD Mon YYYY')</literal>
-        <returnvalue>2000-12-05 00:00:00-05</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <tip>
-    <para>
-     <function>to_timestamp</function> and <function>to_date</function>
-     exist to handle input formats that cannot be converted by
-     simple casting.  For most standard date/time formats, simply casting the
-     source string to the required data type works, and is much easier.
-     Similarly, <function>to_number</function> is unnecessary for standard numeric
-     representations.
-    </para>
-   </tip>
-
-   <para>
-    In a <function>to_char</function> output template string, there are certain
-    patterns that are recognized and replaced with appropriately-formatted
-    data based on the given value.  Any text that is not a template pattern is
-    simply copied verbatim.  Similarly, in an input template string (for the
-    other functions), template patterns identify the values to be supplied by
-    the input data string.  If there are characters in the template string
-    that are not template patterns, the corresponding characters in the input
-    data string are simply skipped over (whether or not they are equal to the
-    template string characters).
-   </para>
-
-  <para>
-   <xref linkend="functions-formatting-datetime-table"/> shows the
-   template patterns available for formatting date and time values.
-  </para>
-
-    <table id="functions-formatting-datetime-table">
-     <title>Template Patterns for Date/Time Formatting</title>
-     <tgroup cols="2">
-      <thead>
-       <row>
-        <entry>Pattern</entry>
-        <entry>Description</entry>
-       </row>
-      </thead>
-      <tbody>
-       <row>
-        <entry><literal>HH</literal></entry>
-        <entry>hour of day (01&ndash;12)</entry>
-       </row>
-       <row>
-        <entry><literal>HH12</literal></entry>
-        <entry>hour of day (01&ndash;12)</entry>
-       </row>
-       <row>
-        <entry><literal>HH24</literal></entry>
-        <entry>hour of day (00&ndash;23)</entry>
-       </row>
-       <row>
-        <entry><literal>MI</literal></entry>
-        <entry>minute (00&ndash;59)</entry>
-       </row>
-       <row>
-        <entry><literal>SS</literal></entry>
-        <entry>second (00&ndash;59)</entry>
-       </row>
-       <row>
-        <entry><literal>MS</literal></entry>
-        <entry>millisecond (000&ndash;999)</entry>
-       </row>
-       <row>
-        <entry><literal>US</literal></entry>
-        <entry>microsecond (000000&ndash;999999)</entry>
-       </row>
-       <row>
-        <entry><literal>FF1</literal></entry>
-        <entry>tenth of second (0&ndash;9)</entry>
-       </row>
-       <row>
-        <entry><literal>FF2</literal></entry>
-        <entry>hundredth of second (00&ndash;99)</entry>
-       </row>
-       <row>
-        <entry><literal>FF3</literal></entry>
-        <entry>millisecond (000&ndash;999)</entry>
-       </row>
-       <row>
-        <entry><literal>FF4</literal></entry>
-        <entry>tenth of a millisecond (0000&ndash;9999)</entry>
-       </row>
-       <row>
-        <entry><literal>FF5</literal></entry>
-        <entry>hundredth of a millisecond (00000&ndash;99999)</entry>
-       </row>
-       <row>
-        <entry><literal>FF6</literal></entry>
-        <entry>microsecond (000000&ndash;999999)</entry>
-       </row>
-       <row>
-        <entry><literal>SSSS</literal>, <literal>SSSSS</literal></entry>
-        <entry>seconds past midnight (0&ndash;86399)</entry>
-       </row>
-       <row>
-        <entry><literal>AM</literal>, <literal>am</literal>,
-        <literal>PM</literal> or <literal>pm</literal></entry>
-        <entry>meridiem indicator (without periods)</entry>
-       </row>
-       <row>
-        <entry><literal>A.M.</literal>, <literal>a.m.</literal>,
-        <literal>P.M.</literal> or <literal>p.m.</literal></entry>
-        <entry>meridiem indicator (with periods)</entry>
-       </row>
-       <row>
-        <entry><literal>Y,YYY</literal></entry>
-        <entry>year (4 or more digits) with comma</entry>
-       </row>
-       <row>
-        <entry><literal>YYYY</literal></entry>
-        <entry>year (4 or more digits)</entry>
-       </row>
-       <row>
-        <entry><literal>YYY</literal></entry>
-        <entry>last 3 digits of year</entry>
-       </row>
-       <row>
-        <entry><literal>YY</literal></entry>
-        <entry>last 2 digits of year</entry>
-       </row>
-       <row>
-        <entry><literal>Y</literal></entry>
-        <entry>last digit of year</entry>
-       </row>
-       <row>
-        <entry><literal>IYYY</literal></entry>
-        <entry>ISO 8601 week-numbering year (4 or more digits)</entry>
-       </row>
-       <row>
-        <entry><literal>IYY</literal></entry>
-        <entry>last 3 digits of ISO 8601 week-numbering year</entry>
-       </row>
-       <row>
-        <entry><literal>IY</literal></entry>
-        <entry>last 2 digits of ISO 8601 week-numbering year</entry>
-       </row>
-       <row>
-        <entry><literal>I</literal></entry>
-        <entry>last digit of ISO 8601 week-numbering year</entry>
-       </row>
-       <row>
-        <entry><literal>BC</literal>, <literal>bc</literal>,
-        <literal>AD</literal> or <literal>ad</literal></entry>
-        <entry>era indicator (without periods)</entry>
-       </row>
-       <row>
-        <entry><literal>B.C.</literal>, <literal>b.c.</literal>,
-        <literal>A.D.</literal> or <literal>a.d.</literal></entry>
-        <entry>era indicator (with periods)</entry>
-       </row>
-       <row>
-        <entry><literal>MONTH</literal></entry>
-        <entry>full upper case month name (blank-padded to 9 chars)</entry>
-       </row>
-       <row>
-        <entry><literal>Month</literal></entry>
-        <entry>full capitalized month name (blank-padded to 9 chars)</entry>
-       </row>
-       <row>
-        <entry><literal>month</literal></entry>
-        <entry>full lower case month name (blank-padded to 9 chars)</entry>
-       </row>
-       <row>
-        <entry><literal>MON</literal></entry>
-        <entry>abbreviated upper case month name (3 chars in English, localized lengths vary)</entry>
-       </row>
-       <row>
-        <entry><literal>Mon</literal></entry>
-        <entry>abbreviated capitalized month name (3 chars in English, localized lengths vary)</entry>
-       </row>
-       <row>
-        <entry><literal>mon</literal></entry>
-        <entry>abbreviated lower case month name (3 chars in English, localized lengths vary)</entry>
-       </row>
-       <row>
-        <entry><literal>MM</literal></entry>
-        <entry>month number (01&ndash;12)</entry>
-       </row>
-       <row>
-        <entry><literal>DAY</literal></entry>
-        <entry>full upper case day name (blank-padded to 9 chars)</entry>
-       </row>
-       <row>
-        <entry><literal>Day</literal></entry>
-        <entry>full capitalized day name (blank-padded to 9 chars)</entry>
-       </row>
-       <row>
-        <entry><literal>day</literal></entry>
-        <entry>full lower case day name (blank-padded to 9 chars)</entry>
-       </row>
-       <row>
-        <entry><literal>DY</literal></entry>
-        <entry>abbreviated upper case day name (3 chars in English, localized lengths vary)</entry>
-       </row>
-       <row>
-        <entry><literal>Dy</literal></entry>
-        <entry>abbreviated capitalized day name (3 chars in English, localized lengths vary)</entry>
-       </row>
-       <row>
-        <entry><literal>dy</literal></entry>
-        <entry>abbreviated lower case day name (3 chars in English, localized lengths vary)</entry>
-       </row>
-       <row>
-        <entry><literal>DDD</literal></entry>
-        <entry>day of year (001&ndash;366)</entry>
-       </row>
-       <row>
-        <entry><literal>IDDD</literal></entry>
-        <entry>day of ISO 8601 week-numbering year (001&ndash;371; day 1 of the year is Monday of the first ISO week)</entry>
-       </row>
-       <row>
-        <entry><literal>DD</literal></entry>
-        <entry>day of month (01&ndash;31)</entry>
-       </row>
-       <row>
-        <entry><literal>D</literal></entry>
-        <entry>day of the week, Sunday (<literal>1</literal>) to Saturday (<literal>7</literal>)</entry>
-       </row>
-       <row>
-        <entry><literal>ID</literal></entry>
-        <entry>ISO 8601 day of the week, Monday (<literal>1</literal>) to Sunday (<literal>7</literal>)</entry>
-       </row>
-       <row>
-        <entry><literal>W</literal></entry>
-        <entry>week of month (1&ndash;5) (the first week starts on the first day of the month)</entry>
-       </row>
-       <row>
-        <entry><literal>WW</literal></entry>
-        <entry>week number of year (1&ndash;53) (the first week starts on the first day of the year)</entry>
-       </row>
-       <row>
-        <entry><literal>IW</literal></entry>
-        <entry>week number of ISO 8601 week-numbering year (01&ndash;53; the first Thursday of the year is in week 1)</entry>
-       </row>
-       <row>
-        <entry><literal>CC</literal></entry>
-        <entry>century (2 digits) (the twenty-first century starts on 2001-01-01)</entry>
-       </row>
-       <row>
-        <entry><literal>J</literal></entry>
-        <entry>Julian Date (integer days since November 24, 4714 BC at local
-        midnight; see <xref linkend="datetime-julian-dates"/>)</entry>
-       </row>
-       <row>
-        <entry><literal>Q</literal></entry>
-        <entry>quarter</entry>
-       </row>
-       <row>
-        <entry><literal>RM</literal></entry>
-        <entry>month in upper case Roman numerals (I&ndash;XII; I=January)</entry>
-       </row>
-       <row>
-        <entry><literal>rm</literal></entry>
-        <entry>month in lower case Roman numerals (i&ndash;xii; i=January)</entry>
-       </row>
-       <row>
-        <entry><literal>TZ</literal></entry>
-        <entry>upper case time-zone abbreviation</entry>
-       </row>
-       <row>
-        <entry><literal>tz</literal></entry>
-        <entry>lower case time-zone abbreviation</entry>
-       </row>
-       <row>
-       <entry><literal>TZH</literal></entry>
-        <entry>time-zone hours</entry>
-       </row>
-       <row>
-       <entry><literal>TZM</literal></entry>
-        <entry>time-zone minutes</entry>
-       </row>
-       <row>
-        <entry><literal>OF</literal></entry>
-        <entry>time-zone offset from UTC (<replaceable>HH</replaceable>
-         or <replaceable>HH</replaceable><literal>:</literal><replaceable>MM</replaceable>)</entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-   <para>
-    Modifiers can be applied to any template pattern to alter its
-    behavior.  For example, <literal>FMMonth</literal>
-    is the <literal>Month</literal> pattern with the
-    <literal>FM</literal> modifier.
-    <xref linkend="functions-formatting-datetimemod-table"/> shows the
-    modifier patterns for date/time formatting.
-   </para>
-
-    <table id="functions-formatting-datetimemod-table">
-     <title>Template Pattern Modifiers for Date/Time Formatting</title>
-     <tgroup cols="3">
-      <thead>
-       <row>
-        <entry>Modifier</entry>
-        <entry>Description</entry>
-        <entry>Example</entry>
-       </row>
-      </thead>
-      <tbody>
-       <row>
-        <entry><literal>FM</literal> prefix</entry>
-        <entry>fill mode (suppress leading zeroes and padding blanks)</entry>
-        <entry><literal>FMMonth</literal></entry>
-       </row>
-       <row>
-        <entry><literal>TH</literal> suffix</entry>
-        <entry>upper case ordinal number suffix</entry>
-        <entry><literal>DDTH</literal>, e.g., <literal>12TH</literal></entry>
-       </row>
-       <row>
-        <entry><literal>th</literal> suffix</entry>
-        <entry>lower case ordinal number suffix</entry>
-        <entry><literal>DDth</literal>, e.g., <literal>12th</literal></entry>
-       </row>
-       <row>
-        <entry><literal>FX</literal> prefix</entry>
-        <entry>fixed format global option (see usage notes)</entry>
-        <entry><literal>FX&nbsp;Month&nbsp;DD&nbsp;Day</literal></entry>
-       </row>
-       <row>
-        <entry><literal>TM</literal> prefix</entry>
-        <entry>translation mode (use localized day and month names based on
-         <xref linkend="guc-lc-time"/>)</entry>
-        <entry><literal>TMMonth</literal></entry>
-       </row>
-       <row>
-        <entry><literal>SP</literal> suffix</entry>
-        <entry>spell mode (not implemented)</entry>
-        <entry><literal>DDSP</literal></entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-   <para>
-    Usage notes for date/time formatting:
-
-    <itemizedlist>
-     <listitem>
-      <para>
-       <literal>FM</literal> suppresses leading zeroes and trailing blanks
-       that would otherwise be added to make the output of a pattern be
-       fixed-width.  In <productname>PostgreSQL</productname>,
-       <literal>FM</literal> modifies only the next specification, while in
-       Oracle <literal>FM</literal> affects all subsequent
-       specifications, and repeated <literal>FM</literal> modifiers
-       toggle fill mode on and off.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       <literal>TM</literal> suppresses trailing blanks whether or
-       not <literal>FM</literal> is specified.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       <function>to_timestamp</function> and <function>to_date</function>
-       ignore letter case in the input; so for
-       example <literal>MON</literal>, <literal>Mon</literal>,
-       and <literal>mon</literal> all accept the same strings.  When using
-       the <literal>TM</literal> modifier, case-folding is done according to
-       the rules of the function's input collation (see
-       <xref linkend="collation"/>).
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       <function>to_timestamp</function> and <function>to_date</function>
-       skip multiple blank spaces at the beginning of the input string and
-       around date and time values unless the <literal>FX</literal> option is used.  For example,
-       <literal>to_timestamp('&nbsp;2000&nbsp;&nbsp;&nbsp;&nbsp;JUN', 'YYYY MON')</literal> and
-       <literal>to_timestamp('2000 - JUN', 'YYYY-MON')</literal> work, but
-       <literal>to_timestamp('2000&nbsp;&nbsp;&nbsp;&nbsp;JUN', 'FXYYYY MON')</literal> returns an error
-       because <function>to_timestamp</function> expects only a single space.
-       <literal>FX</literal> must be specified as the first item in
-       the template.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       A separator (a space or non-letter/non-digit character) in the template string of
-       <function>to_timestamp</function> and <function>to_date</function>
-       matches any single separator in the input string or is skipped,
-       unless the <literal>FX</literal> option is used.
-       For example, <literal>to_timestamp('2000JUN', 'YYYY///MON')</literal> and
-       <literal>to_timestamp('2000/JUN', 'YYYY MON')</literal> work, but
-       <literal>to_timestamp('2000//JUN', 'YYYY/MON')</literal>
-       returns an error because the number of separators in the input string
-       exceeds the number of separators in the template.
-      </para>
-      <para>
-       If <literal>FX</literal> is specified, a separator in the template string
-       matches exactly one character in the input string.  But note that the
-       input string character is not required to be the same as the separator from the template string.
-       For example, <literal>to_timestamp('2000/JUN', 'FXYYYY MON')</literal>
-       works, but <literal>to_timestamp('2000/JUN', 'FXYYYY&nbsp;&nbsp;MON')</literal>
-       returns an error because the second space in the template string consumes
-       the letter <literal>J</literal> from the input string.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       A <literal>TZH</literal> template pattern can match a signed number.
-       Without the <literal>FX</literal> option, minus signs may be ambiguous,
-       and could be interpreted as a separator.
-       This ambiguity is resolved as follows:  If the number of separators before
-       <literal>TZH</literal> in the template string is less than the number of
-       separators before the minus sign in the input string, the minus sign
-       is interpreted as part of <literal>TZH</literal>.
-       Otherwise, the minus sign is considered to be a separator between values.
-       For example, <literal>to_timestamp('2000 -10', 'YYYY TZH')</literal> matches
-       <literal>-10</literal> to <literal>TZH</literal>, but
-       <literal>to_timestamp('2000 -10', 'YYYY&nbsp;&nbsp;TZH')</literal>
-       matches <literal>10</literal> to <literal>TZH</literal>.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       Ordinary text is allowed in <function>to_char</function>
-       templates and will be output literally.  You can put a substring
-       in double quotes to force it to be interpreted as literal text
-       even if it contains template patterns.  For example, in
-       <literal>'"Hello Year "YYYY'</literal>, the <literal>YYYY</literal>
-       will be replaced by the year data, but the single <literal>Y</literal> in <literal>Year</literal>
-       will not be.
-       In <function>to_date</function>, <function>to_number</function>,
-       and <function>to_timestamp</function>, literal text and double-quoted
-       strings result in skipping the number of characters contained in the
-       string; for example <literal>"XX"</literal> skips two input characters
-       (whether or not they are <literal>XX</literal>).
-      </para>
-      <tip>
-        <para>
-          Prior to <productname>PostgreSQL</productname> 12, it was possible to
-          skip arbitrary text in the input string using non-letter or non-digit
-          characters. For example,
-          <literal>to_timestamp('2000y6m1d', 'yyyy-MM-DD')</literal> used to
-          work.  Now you can only use letter characters for this purpose.  For example,
-          <literal>to_timestamp('2000y6m1d', 'yyyytMMtDDt')</literal> and
-          <literal>to_timestamp('2000y6m1d', 'yyyy"y"MM"m"DD"d"')</literal>
-          skip <literal>y</literal>, <literal>m</literal>, and
-          <literal>d</literal>.
-        </para>
-      </tip>
-     </listitem>
-
-     <listitem>
-      <para>
-       If you want to have a double quote in the output you must
-       precede it with a backslash, for example <literal>'\"YYYY
-       Month\"'</literal>. <!-- "" font-lock sanity :-) -->
-       Backslashes are not otherwise special outside of double-quoted
-       strings.  Within a double-quoted string, a backslash causes the
-       next character to be taken literally, whatever it is (but this
-       has no special effect unless the next character is a double quote
-       or another backslash).
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       In <function>to_timestamp</function> and <function>to_date</function>,
-       if the year format specification is less than four digits, e.g.,
-       <literal>YYY</literal>, and the supplied year is less than four digits,
-       the year will be adjusted to be nearest to the year 2020, e.g.,
-       <literal>95</literal> becomes 1995.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       In <function>to_timestamp</function> and <function>to_date</function>,
-       negative years are treated as signifying BC.  If you write both a
-       negative year and an explicit <literal>BC</literal> field, you get AD
-       again.  An input of year zero is treated as 1 BC.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       In <function>to_timestamp</function> and <function>to_date</function>,
-       the <literal>YYYY</literal> conversion has a restriction when
-       processing years with more than 4 digits. You must
-       use some non-digit character or template after <literal>YYYY</literal>,
-       otherwise the year is always interpreted as 4 digits. For example
-       (with the year 20000):
-       <literal>to_date('200001130', 'YYYYMMDD')</literal> will be
-       interpreted as a 4-digit year; instead use a non-digit
-       separator after the year, like
-       <literal>to_date('20000-1130', 'YYYY-MMDD')</literal> or
-       <literal>to_date('20000Nov30', 'YYYYMonDD')</literal>.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       In <function>to_timestamp</function> and <function>to_date</function>,
-       the <literal>CC</literal> (century) field is accepted but ignored
-       if there is a <literal>YYY</literal>, <literal>YYYY</literal> or
-       <literal>Y,YYY</literal> field. If <literal>CC</literal> is used with
-       <literal>YY</literal> or <literal>Y</literal> then the result is
-       computed as that year in the specified century.  If the century is
-       specified but the year is not, the first year of the century
-       is assumed.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       In <function>to_timestamp</function> and <function>to_date</function>,
-       weekday names or numbers (<literal>DAY</literal>, <literal>D</literal>,
-       and related field types) are accepted but are ignored for purposes of
-       computing the result.  The same is true for quarter
-       (<literal>Q</literal>) fields.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       In <function>to_timestamp</function> and <function>to_date</function>,
-       an ISO 8601 week-numbering date (as distinct from a Gregorian date)
-       can be specified in one of two ways:
-       <itemizedlist>
-        <listitem>
-         <para>
-          Year, week number, and weekday:  for
-          example <literal>to_date('2006-42-4', 'IYYY-IW-ID')</literal>
-          returns the date <literal>2006-10-19</literal>.
-          If you omit the weekday it is assumed to be 1 (Monday).
-         </para>
-        </listitem>
-        <listitem>
-         <para>
-          Year and day of year:  for example <literal>to_date('2006-291',
-          'IYYY-IDDD')</literal> also returns <literal>2006-10-19</literal>.
-         </para>
-        </listitem>
-       </itemizedlist>
-      </para>
-      <para>
-       Attempting to enter a date using a mixture of ISO 8601 week-numbering
-       fields and Gregorian date fields is nonsensical, and will cause an
-       error.  In the context of an ISO 8601 week-numbering year, the
-       concept of a <quote>month</quote> or <quote>day of month</quote> has no
-       meaning.  In the context of a Gregorian year, the ISO week has no
-       meaning.
-      </para>
-      <caution>
-       <para>
-        While <function>to_date</function> will reject a mixture of
-        Gregorian and ISO week-numbering date
-        fields, <function>to_char</function> will not, since output format
-        specifications like <literal>YYYY-MM-DD (IYYY-IDDD)</literal> can be
-        useful.  But avoid writing something like <literal>IYYY-MM-DD</literal>;
-        that would yield surprising results near the start of the year.
-        (See <xref linkend="functions-datetime-extract"/> for more
-        information.)
-       </para>
-      </caution>
-     </listitem>
-
-     <listitem>
-      <para>
-       In <function>to_timestamp</function>, millisecond
-       (<literal>MS</literal>) or microsecond (<literal>US</literal>)
-       fields are used as the
-       seconds digits after the decimal point. For example
-       <literal>to_timestamp('12.3', 'SS.MS')</literal> is not 3 milliseconds,
-       but 300, because the conversion treats it as 12 + 0.3 seconds.
-       So, for the format <literal>SS.MS</literal>, the input values
-       <literal>12.3</literal>, <literal>12.30</literal>,
-       and <literal>12.300</literal> specify the
-       same number of milliseconds. To get three milliseconds, one must write
-       <literal>12.003</literal>, which the conversion treats as
-       12 + 0.003 = 12.003 seconds.
-      </para>
-
-      <para>
-       Here is a more
-       complex example:
-       <literal>to_timestamp('15:12:02.020.001230', 'HH24:MI:SS.MS.US')</literal>
-       is 15 hours, 12 minutes, and 2 seconds + 20 milliseconds +
-       1230 microseconds = 2.021230 seconds.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-        <function>to_char(..., 'ID')</function>'s day of the week numbering
-        matches the <function>extract(isodow from ...)</function> function, but
-        <function>to_char(..., 'D')</function>'s does not match
-        <function>extract(dow from ...)</function>'s day numbering.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-        <function>to_char(interval)</function> formats <literal>HH</literal> and
-        <literal>HH12</literal> as shown on a 12-hour clock, for example zero hours
-        and 36 hours both output as <literal>12</literal>, while <literal>HH24</literal>
-        outputs the full hour value, which can exceed 23 in
-        an <type>interval</type> value.
-      </para>
-     </listitem>
-
-    </itemizedlist>
-   </para>
-
-  <para>
-   <xref linkend="functions-formatting-numeric-table"/> shows the
-   template patterns available for formatting numeric values.
-  </para>
-
-    <table id="functions-formatting-numeric-table">
-     <title>Template Patterns for Numeric Formatting</title>
-     <tgroup cols="2">
-      <thead>
-       <row>
-        <entry>Pattern</entry>
-        <entry>Description</entry>
-       </row>
-      </thead>
-      <tbody>
-       <row>
-        <entry><literal>9</literal></entry>
-        <entry>digit position (can be dropped if insignificant)</entry>
-       </row>
-       <row>
-        <entry><literal>0</literal></entry>
-        <entry>digit position (will not be dropped, even if insignificant)</entry>
-       </row>
-       <row>
-        <entry><literal>.</literal> (period)</entry>
-        <entry>decimal point</entry>
-       </row>
-       <row>
-        <entry><literal>,</literal> (comma)</entry>
-        <entry>group (thousands) separator</entry>
-       </row>
-       <row>
-        <entry><literal>PR</literal></entry>
-        <entry>negative value in angle brackets</entry>
-       </row>
-       <row>
-        <entry><literal>S</literal></entry>
-        <entry>sign anchored to number (uses locale)</entry>
-       </row>
-       <row>
-        <entry><literal>L</literal></entry>
-        <entry>currency symbol (uses locale)</entry>
-       </row>
-       <row>
-        <entry><literal>D</literal></entry>
-        <entry>decimal point (uses locale)</entry>
-       </row>
-       <row>
-        <entry><literal>G</literal></entry>
-        <entry>group separator (uses locale)</entry>
-       </row>
-       <row>
-        <entry><literal>MI</literal></entry>
-        <entry>minus sign in specified position (if number &lt; 0)</entry>
-       </row>
-       <row>
-        <entry><literal>PL</literal></entry>
-        <entry>plus sign in specified position (if number &gt; 0)</entry>
-       </row>
-       <row>
-        <entry><literal>SG</literal></entry>
-        <entry>plus/minus sign in specified position</entry>
-       </row>
-       <row>
-        <entry><literal>RN</literal> or <literal>rn</literal></entry>
-        <entry>Roman numeral (values between 1 and 3999)</entry>
-       </row>
-       <row>
-        <entry><literal>TH</literal> or <literal>th</literal></entry>
-        <entry>ordinal number suffix</entry>
-       </row>
-       <row>
-        <entry><literal>V</literal></entry>
-        <entry>shift specified number of digits (see notes)</entry>
-       </row>
-       <row>
-        <entry><literal>EEEE</literal></entry>
-        <entry>exponent for scientific notation</entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-   <para>
-    Usage notes for numeric formatting:
-
-    <itemizedlist>
-     <listitem>
-      <para>
-       <literal>0</literal> specifies a digit position that will always be printed,
-       even if it contains a leading/trailing zero.  <literal>9</literal> also
-       specifies a digit position, but if it is a leading zero then it will
-       be replaced by a space, while if it is a trailing zero and fill mode
-       is specified then it will be deleted.  (For <function>to_number()</function>,
-       these two pattern characters are equivalent.)
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       If the format provides fewer fractional digits than the number being
-       formatted, <function>to_char()</function> will round the number to
-       the specified number of fractional digits.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       The pattern characters <literal>S</literal>, <literal>L</literal>, <literal>D</literal>,
-       and <literal>G</literal> represent the sign, currency symbol, decimal point,
-       and thousands separator characters defined by the current locale
-       (see <xref linkend="guc-lc-monetary"/>
-       and <xref linkend="guc-lc-numeric"/>).  The pattern characters period
-       and comma represent those exact characters, with the meanings of
-       decimal point and thousands separator, regardless of locale.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       If no explicit provision is made for a sign
-       in <function>to_char()</function>'s pattern, one column will be reserved for
-       the sign, and it will be anchored to (appear just left of) the
-       number.  If <literal>S</literal> appears just left of some <literal>9</literal>'s,
-       it will likewise be anchored to the number.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       A sign formatted using <literal>SG</literal>, <literal>PL</literal>, or
-       <literal>MI</literal> is not anchored to
-       the number; for example,
-       <literal>to_char(-12, 'MI9999')</literal> produces <literal>'-&nbsp;&nbsp;12'</literal>
-       but <literal>to_char(-12, 'S9999')</literal> produces <literal>'&nbsp;&nbsp;-12'</literal>.
-       (The Oracle implementation does not allow the use of
-       <literal>MI</literal> before <literal>9</literal>, but rather
-       requires that <literal>9</literal> precede
-       <literal>MI</literal>.)
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       <literal>TH</literal> does not convert values less than zero
-       and does not convert fractional numbers.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       <literal>PL</literal>, <literal>SG</literal>, and
-       <literal>TH</literal> are <productname>PostgreSQL</productname>
-       extensions.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       In <function>to_number</function>, if non-data template patterns such
-       as <literal>L</literal> or <literal>TH</literal> are used, the
-       corresponding number of input characters are skipped, whether or not
-       they match the template pattern, unless they are data characters
-       (that is, digits, sign, decimal point, or comma).  For
-       example, <literal>TH</literal> would skip two non-data characters.
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       <literal>V</literal> with <function>to_char</function>
-       multiplies the input values by
-       <literal>10^<replaceable>n</replaceable></literal>, where
-       <replaceable>n</replaceable> is the number of digits following
-       <literal>V</literal>.  <literal>V</literal> with
-       <function>to_number</function> divides in a similar manner.
-       The <literal>V</literal> can be thought of as marking the position
-       of an implicit decimal point in the input or output string.
-       <function>to_char</function> and <function>to_number</function>
-       do not support the use of
-       <literal>V</literal> combined with a decimal point
-       (e.g., <literal>99.9V99</literal> is not allowed).
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       <literal>EEEE</literal> (scientific notation) cannot be used in
-       combination with any of the other formatting patterns or
-       modifiers other than digit and decimal point patterns, and must be at the end of the format string
-       (e.g., <literal>9.99EEEE</literal> is a valid pattern).
-      </para>
-     </listitem>
-
-     <listitem>
-      <para>
-       In <function>to_number()</function>, the <literal>RN</literal>
-       pattern converts Roman numerals (in standard form) to numbers.
-       Input is case-insensitive, so <literal>RN</literal>
-       and <literal>rn</literal> are equivalent.  <literal>RN</literal>
-       cannot be used in combination with any other formatting patterns or
-       modifiers except <literal>FM</literal>, which is applicable only
-       in <function>to_char()</function> and is ignored
-       in <function>to_number()</function>.
-      </para>
-     </listitem>
-    </itemizedlist>
-   </para>
-
-   <para>
-    Certain modifiers can be applied to any template pattern to alter its
-    behavior.  For example, <literal>FM99.99</literal>
-    is the <literal>99.99</literal> pattern with the
-    <literal>FM</literal> modifier.
-    <xref linkend="functions-formatting-numericmod-table"/> shows the
-    modifier patterns for numeric formatting.
-   </para>
-
-    <table id="functions-formatting-numericmod-table">
-     <title>Template Pattern Modifiers for Numeric Formatting</title>
-     <tgroup cols="3">
-      <thead>
-       <row>
-        <entry>Modifier</entry>
-        <entry>Description</entry>
-        <entry>Example</entry>
-       </row>
-      </thead>
-      <tbody>
-       <row>
-        <entry><literal>FM</literal> prefix</entry>
-        <entry>fill mode (suppress trailing zeroes and padding blanks)</entry>
-        <entry><literal>FM99.99</literal></entry>
-       </row>
-       <row>
-        <entry><literal>TH</literal> suffix</entry>
-        <entry>upper case ordinal number suffix</entry>
-        <entry><literal>999TH</literal></entry>
-       </row>
-       <row>
-        <entry><literal>th</literal> suffix</entry>
-        <entry>lower case ordinal number suffix</entry>
-        <entry><literal>999th</literal></entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-  <para>
-   <xref linkend="functions-formatting-examples-table"/> shows some
-   examples of the use of the <function>to_char</function> function.
-  </para>
-
-    <table id="functions-formatting-examples-table">
-     <title><function>to_char</function> Examples</title>
-     <tgroup cols="2">
-      <thead>
-       <row>
-        <entry>Expression</entry>
-        <entry>Result</entry>
-       </row>
-      </thead>
-      <tbody>
-       <row>
-        <entry><literal>to_char(current_timestamp, 'Day,&nbsp;DD&nbsp;&nbsp;HH12:MI:SS')</literal></entry>
-        <entry><literal>'Tuesday&nbsp;&nbsp;,&nbsp;06&nbsp;&nbsp;05:39:18'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(current_timestamp, 'FMDay,&nbsp;FMDD&nbsp;&nbsp;HH12:MI:SS')</literal></entry>
-        <entry><literal>'Tuesday,&nbsp;6&nbsp;&nbsp;05:39:18'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(current_timestamp AT TIME ZONE
-        'UTC', 'YYYY-MM-DD"T"HH24:MI:SS"Z"')</literal></entry>
-        <entry><literal>'2022-12-06T05:39:18Z'</literal>,
-        <acronym>ISO</acronym> 8601 extended format</entry>
-       </row>
-       <row>
-        <entry><literal>to_char(-0.1, '99.99')</literal></entry>
-        <entry><literal>'&nbsp;&nbsp;-.10'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(-0.1, 'FM9.99')</literal></entry>
-        <entry><literal>'-.1'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(-0.1, 'FM90.99')</literal></entry>
-        <entry><literal>'-0.1'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(0.1, '0.9')</literal></entry>
-        <entry><literal>'&nbsp;0.1'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(12, '9990999.9')</literal></entry>
-        <entry><literal>'&nbsp;&nbsp;&nbsp;&nbsp;0012.0'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(12, 'FM9990999.9')</literal></entry>
-        <entry><literal>'0012.'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(485, '999')</literal></entry>
-        <entry><literal>'&nbsp;485'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(-485, '999')</literal></entry>
-        <entry><literal>'-485'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(485, '9&nbsp;9&nbsp;9')</literal></entry>
-        <entry><literal>'&nbsp;4&nbsp;8&nbsp;5'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(1485, '9,999')</literal></entry>
-        <entry><literal>'&nbsp;1,485'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(1485, '9G999')</literal></entry>
-        <entry><literal>'&nbsp;1&nbsp;485'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(148.5, '999.999')</literal></entry>
-        <entry><literal>'&nbsp;148.500'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(148.5, 'FM999.999')</literal></entry>
-        <entry><literal>'148.5'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(148.5, 'FM999.990')</literal></entry>
-        <entry><literal>'148.500'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(148.5, '999D999')</literal></entry>
-        <entry><literal>'&nbsp;148,500'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(3148.5, '9G999D999')</literal></entry>
-        <entry><literal>'&nbsp;3&nbsp;148,500'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(-485, '999S')</literal></entry>
-        <entry><literal>'485-'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(-485, '999MI')</literal></entry>
-        <entry><literal>'485-'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(485, '999MI')</literal></entry>
-        <entry><literal>'485&nbsp;'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(485, 'FM999MI')</literal></entry>
-        <entry><literal>'485'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(485, 'PL999')</literal></entry>
-        <entry><literal>'+485'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(485, 'SG999')</literal></entry>
-        <entry><literal>'+485'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(-485, 'SG999')</literal></entry>
-        <entry><literal>'-485'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(-485, '9SG99')</literal></entry>
-        <entry><literal>'4-85'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(-485, '999PR')</literal></entry>
-        <entry><literal>'&lt;485&gt;'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(485, 'L999')</literal></entry>
-        <entry><literal>'DM&nbsp;485'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(485, 'RN')</literal></entry>
-        <entry><literal>'&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;CDLXXXV'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(485, 'FMRN')</literal></entry>
-        <entry><literal>'CDLXXXV'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(5.2, 'FMRN')</literal></entry>
-        <entry><literal>'V'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(482, '999th')</literal></entry>
-        <entry><literal>'&nbsp;482nd'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(485, '"Good&nbsp;number:"999')</literal></entry>
-        <entry><literal>'Good&nbsp;number:&nbsp;485'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(485.8, '"Pre:"999"&nbsp;Post:"&nbsp;.999')</literal></entry>
-        <entry><literal>'Pre:&nbsp;485&nbsp;Post:&nbsp;.800'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(12, '99V999')</literal></entry>
-        <entry><literal>'&nbsp;12000'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(12.4, '99V999')</literal></entry>
-        <entry><literal>'&nbsp;12400'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(12.45, '99V9')</literal></entry>
-        <entry><literal>'&nbsp;125'</literal></entry>
-       </row>
-       <row>
-        <entry><literal>to_char(0.0004859, '9.99EEEE')</literal></entry>
-        <entry><literal>' 4.86e-04'</literal></entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-  </sect1>
-
-
-  <sect1 id="functions-datetime">
-   <title>Date/Time Functions and Operators</title>
-
-  <para>
-   <xref linkend="functions-datetime-table"/> shows the available
-   functions for date/time value processing, with details appearing in
-   the following subsections.  <xref
-   linkend="operators-datetime-table"/> illustrates the behaviors of
-   the basic arithmetic operators (<literal>+</literal>,
-   <literal>*</literal>, etc.).  For formatting functions, refer to
-   <xref linkend="functions-formatting"/>.  You should be familiar with
-   the background information on date/time data types from <xref
-   linkend="datatype-datetime"/>.
-  </para>
-
-  <para>
-   In addition, the usual comparison operators shown in
-   <xref linkend="functions-comparison-op-table"/> are available for the
-   date/time types.  Dates and timestamps (with or without time zone) are
-   all comparable, while times (with or without time zone) and intervals
-   can only be compared to other values of the same data type.  When
-   comparing a timestamp without time zone to a timestamp with time zone,
-   the former value is assumed to be given in the time zone specified by
-   the <xref linkend="guc-timezone"/> configuration parameter, and is
-   rotated to UTC for comparison to the latter value (which is already
-   in UTC internally).  Similarly, a date value is assumed to represent
-   midnight in the <varname>TimeZone</varname> zone when comparing it
-   to a timestamp.
-  </para>
-
-  <para>
-   All the functions and operators described below that take <type>time</type> or <type>timestamp</type>
-   inputs actually come in two variants: one that takes <type>time with time zone</type> or <type>timestamp
-   with time zone</type>, and one that takes <type>time without time zone</type> or <type>timestamp without time zone</type>.
-   For brevity, these variants are not shown separately.  Also, the
-   <literal>+</literal> and <literal>*</literal> operators come in commutative pairs (for
-   example both <type>date</type> <literal>+</literal> <type>integer</type>
-   and <type>integer</type> <literal>+</literal> <type>date</type>); we show
-   only one of each such pair.
-  </para>
-
-    <table id="operators-datetime-table">
-     <title>Date/Time Operators</title>
-
-     <tgroup cols="1">
-      <thead>
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         Operator
-        </para>
-        <para>
-         Description
-        </para>
-        <para>
-         Example(s)
-        </para></entry>
-       </row>
-      </thead>
-
-      <tbody>
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>date</type> <literal>+</literal> <type>integer</type>
-         <returnvalue>date</returnvalue>
-        </para>
-        <para>
-         Add a number of days to a date
-        </para>
-        <para>
-         <literal>date '2001-09-28' + 7</literal>
-         <returnvalue>2001-10-05</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>date</type> <literal>+</literal> <type>interval</type>
-         <returnvalue>timestamp</returnvalue>
-        </para>
-        <para>
-         Add an interval to a date
-        </para>
-        <para>
-         <literal>date '2001-09-28' + interval '1 hour'</literal>
-         <returnvalue>2001-09-28 01:00:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>date</type> <literal>+</literal> <type>time</type>
-         <returnvalue>timestamp</returnvalue>
-        </para>
-        <para>
-         Add a time-of-day to a date
-        </para>
-        <para>
-         <literal>date '2001-09-28' + time '03:00'</literal>
-         <returnvalue>2001-09-28 03:00:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>interval</type> <literal>+</literal> <type>interval</type>
-         <returnvalue>interval</returnvalue>
-        </para>
-        <para>
-         Add intervals
-        </para>
-        <para>
-         <literal>interval '1 day' + interval '1 hour'</literal>
-         <returnvalue>1 day 01:00:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>timestamp</type> <literal>+</literal> <type>interval</type>
-         <returnvalue>timestamp</returnvalue>
-        </para>
-        <para>
-         Add an interval to a timestamp
-        </para>
-        <para>
-         <literal>timestamp '2001-09-28 01:00' + interval '23 hours'</literal>
-         <returnvalue>2001-09-29 00:00:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>time</type> <literal>+</literal> <type>interval</type>
-         <returnvalue>time</returnvalue>
-        </para>
-        <para>
-         Add an interval to a time
-        </para>
-        <para>
-         <literal>time '01:00' + interval '3 hours'</literal>
-         <returnvalue>04:00:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <literal>-</literal> <type>interval</type>
-         <returnvalue>interval</returnvalue>
-        </para>
-        <para>
-         Negate an interval
-        </para>
-        <para>
-         <literal>- interval '23 hours'</literal>
-         <returnvalue>-23:00:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>date</type> <literal>-</literal> <type>date</type>
-         <returnvalue>integer</returnvalue>
-        </para>
-        <para>
-         Subtract dates, producing the number of days elapsed
-        </para>
-        <para>
-         <literal>date '2001-10-01' - date '2001-09-28'</literal>
-         <returnvalue>3</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>date</type> <literal>-</literal> <type>integer</type>
-         <returnvalue>date</returnvalue>
-        </para>
-        <para>
-         Subtract a number of days from a date
-        </para>
-        <para>
-         <literal>date '2001-10-01' - 7</literal>
-         <returnvalue>2001-09-24</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>date</type> <literal>-</literal> <type>interval</type>
-         <returnvalue>timestamp</returnvalue>
-        </para>
-        <para>
-         Subtract an interval from a date
-        </para>
-        <para>
-         <literal>date '2001-09-28' - interval '1 hour'</literal>
-         <returnvalue>2001-09-27 23:00:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>time</type> <literal>-</literal> <type>time</type>
-         <returnvalue>interval</returnvalue>
-        </para>
-        <para>
-         Subtract times
-        </para>
-        <para>
-         <literal>time '05:00' - time '03:00'</literal>
-         <returnvalue>02:00:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>time</type> <literal>-</literal> <type>interval</type>
-         <returnvalue>time</returnvalue>
-        </para>
-        <para>
-         Subtract an interval from a time
-        </para>
-        <para>
-         <literal>time '05:00' - interval '2 hours'</literal>
-         <returnvalue>03:00:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>timestamp</type> <literal>-</literal> <type>interval</type>
-         <returnvalue>timestamp</returnvalue>
-        </para>
-        <para>
-         Subtract an interval from a timestamp
-        </para>
-        <para>
-         <literal>timestamp '2001-09-28 23:00' - interval '23 hours'</literal>
-         <returnvalue>2001-09-28 00:00:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>interval</type> <literal>-</literal> <type>interval</type>
-         <returnvalue>interval</returnvalue>
-        </para>
-        <para>
-         Subtract intervals
-        </para>
-        <para>
-         <literal>interval '1 day' - interval '1 hour'</literal>
-         <returnvalue>1 day -01:00:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>timestamp</type> <literal>-</literal> <type>timestamp</type>
-         <returnvalue>interval</returnvalue>
-        </para>
-        <para>
-         Subtract timestamps (converting 24-hour intervals into days,
-         similarly to <link
-         linkend="function-justify-hours"><function>justify_hours()</function></link>)
-        </para>
-        <para>
-         <literal>timestamp '2001-09-29 03:00' - timestamp '2001-07-27 12:00'</literal>
-         <returnvalue>63 days 15:00:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>interval</type> <literal>*</literal> <type>double precision</type>
-         <returnvalue>interval</returnvalue>
-        </para>
-        <para>
-         Multiply an interval by a scalar
-        </para>
-        <para>
-         <literal>interval '1 second' * 900</literal>
-         <returnvalue>00:15:00</returnvalue>
-        </para>
-        <para>
-         <literal>interval '1 day' * 21</literal>
-         <returnvalue>21 days</returnvalue>
-        </para>
-        <para>
-         <literal>interval '1 hour' * 3.5</literal>
-         <returnvalue>03:30:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>interval</type> <literal>/</literal> <type>double precision</type>
-         <returnvalue>interval</returnvalue>
-        </para>
-        <para>
-         Divide an interval by a scalar
-        </para>
-        <para>
-         <literal>interval '1 hour' / 1.5</literal>
-         <returnvalue>00:40:00</returnvalue>
-        </para></entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-    <table id="functions-datetime-table">
-     <title>Date/Time Functions</title>
-     <tgroup cols="1">
-      <thead>
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         Function
-        </para>
-        <para>
-         Description
-        </para>
-        <para>
-         Example(s)
-        </para></entry>
-       </row>
-      </thead>
-
-      <tbody>
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>age</primary>
-         </indexterm>
-         <function>age</function> ( <type>timestamp</type>, <type>timestamp</type> )
-         <returnvalue>interval</returnvalue>
-        </para>
-        <para>
-         Subtract arguments, producing a <quote>symbolic</quote> result that
-         uses years and months, rather than just days
-        </para>
-        <para>
-         <literal>age(timestamp '2001-04-10', timestamp '1957-06-13')</literal>
-         <returnvalue>43 years 9 mons 27 days</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <function>age</function> ( <type>timestamp</type> )
-         <returnvalue>interval</returnvalue>
-        </para>
-        <para>
-         Subtract argument from <function>current_date</function> (at midnight)
-        </para>
-        <para>
-         <literal>age(timestamp '1957-06-13')</literal>
-         <returnvalue>62 years 6 mons 10 days</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>clock_timestamp</primary>
-         </indexterm>
-         <function>clock_timestamp</function> ( )
-         <returnvalue>timestamp with time zone</returnvalue>
-        </para>
-        <para>
-         Current date and time (changes during statement execution);
-         see <xref linkend="functions-datetime-current"/>
-        </para>
-        <para>
-         <literal>clock_timestamp()</literal>
-         <returnvalue>2019-12-23 14:39:53.662522-05</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>current_date</primary>
-         </indexterm>
-         <function>current_date</function>
-         <returnvalue>date</returnvalue>
-        </para>
-        <para>
-         Current date; see <xref linkend="functions-datetime-current"/>
-        </para>
-        <para>
-         <literal>current_date</literal>
-         <returnvalue>2019-12-23</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>current_time</primary>
-         </indexterm>
-         <function>current_time</function>
-         <returnvalue>time with time zone</returnvalue>
-        </para>
-        <para>
-         Current time of day; see <xref linkend="functions-datetime-current"/>
-        </para>
-        <para>
-         <literal>current_time</literal>
-         <returnvalue>14:39:53.662522-05</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <function>current_time</function> ( <type>integer</type> )
-         <returnvalue>time with time zone</returnvalue>
-        </para>
-        <para>
-         Current time of day, with limited precision;
-         see <xref linkend="functions-datetime-current"/>
-        </para>
-        <para>
-         <literal>current_time(2)</literal>
-         <returnvalue>14:39:53.66-05</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>current_timestamp</primary>
-         </indexterm>
-         <function>current_timestamp</function>
-         <returnvalue>timestamp with time zone</returnvalue>
-        </para>
-        <para>
-         Current date and time (start of current transaction);
-         see <xref linkend="functions-datetime-current"/>
-        </para>
-        <para>
-         <literal>current_timestamp</literal>
-         <returnvalue>2019-12-23 14:39:53.662522-05</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <function>current_timestamp</function> ( <type>integer</type> )
-         <returnvalue>timestamp with time zone</returnvalue>
-        </para>
-        <para>
-         Current date and time (start of current transaction), with limited precision;
-         see <xref linkend="functions-datetime-current"/>
-        </para>
-        <para>
-         <literal>current_timestamp(0)</literal>
-         <returnvalue>2019-12-23 14:39:53-05</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>date_add</primary>
-         </indexterm>
-         <function>date_add</function> ( <type>timestamp with time zone</type>, <type>interval</type> <optional>, <type>text</type> </optional> )
-         <returnvalue>timestamp with time zone</returnvalue>
-        </para>
-        <para>
-         Add an <type>interval</type> to a <type>timestamp with time
-         zone</type>, computing times of day and daylight-savings adjustments
-         according to the time zone named by the third argument, or the
-         current <xref linkend="guc-timezone"/> setting if that is omitted.
-         The form with two arguments is equivalent to the <type>timestamp with
-         time zone</type> <literal>+</literal> <type>interval</type> operator.
-        </para>
-        <para>
-         <literal>date_add('2021-10-31 00:00:00+02'::timestamptz, '1 day'::interval, 'Europe/Warsaw')</literal>
-         <returnvalue>2021-10-31 23:00:00+00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <function>date_bin</function> ( <type>interval</type>, <type>timestamp</type>, <type>timestamp</type> )
-         <returnvalue>timestamp</returnvalue>
-        </para>
-        <para>
-         Bin input into specified interval aligned with specified origin; see <xref linkend="functions-datetime-bin"/>
-        </para>
-        <para>
-         <literal>date_bin('15 minutes', timestamp '2001-02-16 20:38:40', timestamp '2001-02-16 20:05:00')</literal>
-         <returnvalue>2001-02-16 20:35:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>date_part</primary>
-         </indexterm>
-         <function>date_part</function> ( <type>text</type>, <type>timestamp</type> )
-         <returnvalue>double precision</returnvalue>
-        </para>
-        <para>
-         Get timestamp subfield (equivalent to <function>extract</function>);
-         see <xref linkend="functions-datetime-extract"/>
-        </para>
-        <para>
-         <literal>date_part('hour', timestamp '2001-02-16 20:38:40')</literal>
-         <returnvalue>20</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <function>date_part</function> ( <type>text</type>, <type>interval</type> )
-         <returnvalue>double precision</returnvalue>
-        </para>
-        <para>
-         Get interval subfield (equivalent to <function>extract</function>);
-         see <xref linkend="functions-datetime-extract"/>
-        </para>
-        <para>
-         <literal>date_part('month', interval '2 years 3 months')</literal>
-         <returnvalue>3</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>date_subtract</primary>
-         </indexterm>
-         <function>date_subtract</function> ( <type>timestamp with time zone</type>, <type>interval</type> <optional>, <type>text</type> </optional> )
-         <returnvalue>timestamp with time zone</returnvalue>
-        </para>
-        <para>
-         Subtract an <type>interval</type> from a <type>timestamp with time
-         zone</type>, computing times of day and daylight-savings adjustments
-         according to the time zone named by the third argument, or the
-         current <xref linkend="guc-timezone"/> setting if that is omitted.
-         The form with two arguments is equivalent to the <type>timestamp with
-         time zone</type> <literal>-</literal> <type>interval</type> operator.
-        </para>
-        <para>
-         <literal>date_subtract('2021-11-01 00:00:00+01'::timestamptz, '1 day'::interval, 'Europe/Warsaw')</literal>
-         <returnvalue>2021-10-30 22:00:00+00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>date_trunc</primary>
-         </indexterm>
-         <function>date_trunc</function> ( <type>text</type>, <type>timestamp</type> )
-         <returnvalue>timestamp</returnvalue>
-        </para>
-        <para>
-         Truncate to specified precision; see <xref linkend="functions-datetime-trunc"/>
-        </para>
-        <para>
-         <literal>date_trunc('hour', timestamp '2001-02-16 20:38:40')</literal>
-         <returnvalue>2001-02-16 20:00:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <function>date_trunc</function> ( <type>text</type>, <type>timestamp with time zone</type>, <type>text</type> )
-         <returnvalue>timestamp with time zone</returnvalue>
-        </para>
-        <para>
-         Truncate to specified precision in the specified time zone; see
-         <xref linkend="functions-datetime-trunc"/>
-        </para>
-        <para>
-         <literal>date_trunc('day', timestamptz '2001-02-16 20:38:40+00', 'Australia/Sydney')</literal>
-         <returnvalue>2001-02-16 13:00:00+00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <function>date_trunc</function> ( <type>text</type>, <type>interval</type> )
-         <returnvalue>interval</returnvalue>
-        </para>
-        <para>
-         Truncate to specified precision; see
-         <xref linkend="functions-datetime-trunc"/>
-        </para>
-        <para>
-         <literal>date_trunc('hour', interval '2 days 3 hours 40 minutes')</literal>
-         <returnvalue>2 days 03:00:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>extract</primary>
-         </indexterm>
-         <function>extract</function> ( <parameter>field</parameter> <literal>from</literal> <type>timestamp</type> )
-         <returnvalue>numeric</returnvalue>
-        </para>
-        <para>
-         Get timestamp subfield; see <xref linkend="functions-datetime-extract"/>
-        </para>
-        <para>
-         <literal>extract(hour from timestamp '2001-02-16 20:38:40')</literal>
-         <returnvalue>20</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <function>extract</function> ( <parameter>field</parameter> <literal>from</literal> <type>interval</type> )
-         <returnvalue>numeric</returnvalue>
-        </para>
-        <para>
-         Get interval subfield; see <xref linkend="functions-datetime-extract"/>
-        </para>
-        <para>
-         <literal>extract(month from interval '2 years 3 months')</literal>
-         <returnvalue>3</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>isfinite</primary>
-         </indexterm>
-         <function>isfinite</function> ( <type>date</type> )
-         <returnvalue>boolean</returnvalue>
-        </para>
-        <para>
-         Test for finite date (not +/-infinity)
-        </para>
-        <para>
-         <literal>isfinite(date '2001-02-16')</literal>
-         <returnvalue>true</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <function>isfinite</function> ( <type>timestamp</type> )
-         <returnvalue>boolean</returnvalue>
-        </para>
-        <para>
-         Test for finite timestamp (not +/-infinity)
-        </para>
-        <para>
-         <literal>isfinite(timestamp 'infinity')</literal>
-         <returnvalue>false</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <function>isfinite</function> ( <type>interval</type> )
-         <returnvalue>boolean</returnvalue>
-        </para>
-        <para>
-         Test for finite interval (not +/-infinity)
-        </para>
-        <para>
-         <literal>isfinite(interval '4 hours')</literal>
-         <returnvalue>true</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm id="function-justify-days">
-          <primary>justify_days</primary>
-         </indexterm>
-         <function>justify_days</function> ( <type>interval</type> )
-         <returnvalue>interval</returnvalue>
-        </para>
-        <para>
-         Adjust interval, converting 30-day time periods to months
-        </para>
-        <para>
-         <literal>justify_days(interval '1 year 65 days')</literal>
-         <returnvalue>1 year 2 mons 5 days</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm id="function-justify-hours">
-          <primary>justify_hours</primary>
-         </indexterm>
-         <function>justify_hours</function> ( <type>interval</type> )
-         <returnvalue>interval</returnvalue>
-        </para>
-        <para>
-         Adjust interval, converting 24-hour time periods to days
-        </para>
-        <para>
-         <literal>justify_hours(interval '50 hours 10 minutes')</literal>
-         <returnvalue>2 days 02:10:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>justify_interval</primary>
-         </indexterm>
-         <function>justify_interval</function> ( <type>interval</type> )
-         <returnvalue>interval</returnvalue>
-        </para>
-        <para>
-         Adjust interval using <function>justify_days</function>
-         and <function>justify_hours</function>, with additional sign
-         adjustments
-        </para>
-        <para>
-         <literal>justify_interval(interval '1 mon -1 hour')</literal>
-         <returnvalue>29 days 23:00:00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>localtime</primary>
-         </indexterm>
-         <function>localtime</function>
-         <returnvalue>time</returnvalue>
-        </para>
-        <para>
-         Current time of day;
-         see <xref linkend="functions-datetime-current"/>
-        </para>
-        <para>
-         <literal>localtime</literal>
-         <returnvalue>14:39:53.662522</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <function>localtime</function> ( <type>integer</type> )
-         <returnvalue>time</returnvalue>
-        </para>
-        <para>
-         Current time of day, with limited precision;
-         see <xref linkend="functions-datetime-current"/>
-        </para>
-        <para>
-         <literal>localtime(0)</literal>
-         <returnvalue>14:39:53</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>localtimestamp</primary>
-         </indexterm>
-         <function>localtimestamp</function>
-         <returnvalue>timestamp</returnvalue>
-        </para>
-        <para>
-         Current date and time (start of current transaction);
-         see <xref linkend="functions-datetime-current"/>
-        </para>
-        <para>
-         <literal>localtimestamp</literal>
-         <returnvalue>2019-12-23 14:39:53.662522</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <function>localtimestamp</function> ( <type>integer</type> )
-         <returnvalue>timestamp</returnvalue>
-        </para>
-        <para>
-         Current date and time (start of current
-         transaction), with limited precision;
-         see <xref linkend="functions-datetime-current"/>
-        </para>
-        <para>
-         <literal>localtimestamp(2)</literal>
-         <returnvalue>2019-12-23 14:39:53.66</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>make_date</primary>
-         </indexterm>
-         <function>make_date</function> ( <parameter>year</parameter> <type>int</type>,
-         <parameter>month</parameter> <type>int</type>,
-         <parameter>day</parameter> <type>int</type> )
-         <returnvalue>date</returnvalue>
-        </para>
-        <para>
-         Create date from year, month and day fields
-         (negative years signify BC)
-        </para>
-        <para>
-         <literal>make_date(2013, 7, 15)</literal>
-         <returnvalue>2013-07-15</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature"><indexterm>
-          <primary>make_interval</primary>
-         </indexterm>
-         <function>make_interval</function> ( <optional> <parameter>years</parameter> <type>int</type>
-         <optional>, <parameter>months</parameter> <type>int</type>
-         <optional>, <parameter>weeks</parameter> <type>int</type>
-         <optional>, <parameter>days</parameter> <type>int</type>
-         <optional>, <parameter>hours</parameter> <type>int</type>
-         <optional>, <parameter>mins</parameter> <type>int</type>
-         <optional>, <parameter>secs</parameter> <type>double precision</type>
-         </optional></optional></optional></optional></optional></optional></optional> )
-         <returnvalue>interval</returnvalue>
-        </para>
-        <para>
-         Create interval from years, months, weeks, days, hours, minutes and
-         seconds fields, each of which can default to zero
-        </para>
-        <para>
-         <literal>make_interval(days =&gt; 10)</literal>
-         <returnvalue>10 days</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>make_time</primary>
-         </indexterm>
-         <function>make_time</function> ( <parameter>hour</parameter> <type>int</type>,
-         <parameter>min</parameter> <type>int</type>,
-         <parameter>sec</parameter> <type>double precision</type> )
-         <returnvalue>time</returnvalue>
-        </para>
-        <para>
-         Create time from hour, minute and seconds fields
-        </para>
-        <para>
-         <literal>make_time(8, 15, 23.5)</literal>
-         <returnvalue>08:15:23.5</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>make_timestamp</primary>
-         </indexterm>
-         <function>make_timestamp</function> ( <parameter>year</parameter> <type>int</type>,
-         <parameter>month</parameter> <type>int</type>,
-         <parameter>day</parameter> <type>int</type>,
-         <parameter>hour</parameter> <type>int</type>,
-         <parameter>min</parameter> <type>int</type>,
-         <parameter>sec</parameter> <type>double precision</type> )
-         <returnvalue>timestamp</returnvalue>
-        </para>
-        <para>
-         Create timestamp from year, month, day, hour, minute and seconds fields
-         (negative years signify BC)
-        </para>
-        <para>
-         <literal>make_timestamp(2013, 7, 15, 8, 15, 23.5)</literal>
-         <returnvalue>2013-07-15 08:15:23.5</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>make_timestamptz</primary>
-         </indexterm>
-         <function>make_timestamptz</function> ( <parameter>year</parameter> <type>int</type>,
-         <parameter>month</parameter> <type>int</type>,
-         <parameter>day</parameter> <type>int</type>,
-         <parameter>hour</parameter> <type>int</type>,
-         <parameter>min</parameter> <type>int</type>,
-         <parameter>sec</parameter> <type>double precision</type>
-         <optional>, <parameter>timezone</parameter> <type>text</type> </optional> )
-         <returnvalue>timestamp with time zone</returnvalue>
-        </para>
-        <para>
-         Create timestamp with time zone from year, month, day, hour, minute
-         and seconds fields (negative years signify BC).
-         If <parameter>timezone</parameter> is not
-         specified, the current time zone is used; the examples assume the
-         session time zone is <literal>Europe/London</literal>
-        </para>
-        <para>
-         <literal>make_timestamptz(2013, 7, 15, 8, 15, 23.5)</literal>
-         <returnvalue>2013-07-15 08:15:23.5+01</returnvalue>
-        </para>
-        <para>
-         <literal>make_timestamptz(2013, 7, 15, 8, 15, 23.5, 'America/New_York')</literal>
-         <returnvalue>2013-07-15 13:15:23.5+01</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>now</primary>
-         </indexterm>
-         <function>now</function> ( )
-         <returnvalue>timestamp with time zone</returnvalue>
-        </para>
-        <para>
-         Current date and time (start of current transaction);
-         see <xref linkend="functions-datetime-current"/>
-        </para>
-        <para>
-         <literal>now()</literal>
-         <returnvalue>2019-12-23 14:39:53.662522-05</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>statement_timestamp</primary>
-         </indexterm>
-         <function>statement_timestamp</function> ( )
-         <returnvalue>timestamp with time zone</returnvalue>
-        </para>
-        <para>
-         Current date and time (start of current statement);
-         see <xref linkend="functions-datetime-current"/>
-        </para>
-        <para>
-         <literal>statement_timestamp()</literal>
-         <returnvalue>2019-12-23 14:39:53.662522-05</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>timeofday</primary>
-         </indexterm>
-         <function>timeofday</function> ( )
-         <returnvalue>text</returnvalue>
-        </para>
-        <para>
-         Current date and time
-         (like <function>clock_timestamp</function>, but as a <type>text</type> string);
-         see <xref linkend="functions-datetime-current"/>
-        </para>
-        <para>
-         <literal>timeofday()</literal>
-         <returnvalue>Mon Dec 23 14:39:53.662522 2019 EST</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>transaction_timestamp</primary>
-         </indexterm>
-         <function>transaction_timestamp</function> ( )
-         <returnvalue>timestamp with time zone</returnvalue>
-        </para>
-        <para>
-         Current date and time (start of current transaction);
-         see <xref linkend="functions-datetime-current"/>
-        </para>
-        <para>
-         <literal>transaction_timestamp()</literal>
-         <returnvalue>2019-12-23 14:39:53.662522-05</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>to_timestamp</primary>
-         </indexterm>
-         <function>to_timestamp</function> ( <type>double precision</type> )
-         <returnvalue>timestamp with time zone</returnvalue>
-        </para>
-        <para>
-         Convert Unix epoch (seconds since 1970-01-01 00:00:00+00) to
-         timestamp with time zone
-        </para>
-        <para>
-         <literal>to_timestamp(1284352323)</literal>
-         <returnvalue>2010-09-13 04:32:03+00</returnvalue>
-        </para></entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-   <para>
-    <indexterm>
-      <primary>OVERLAPS</primary>
-    </indexterm>
-    In addition to these functions, the SQL <literal>OVERLAPS</literal> operator is
-    supported:
-<synopsis>
-(<replaceable>start1</replaceable>, <replaceable>end1</replaceable>) OVERLAPS (<replaceable>start2</replaceable>, <replaceable>end2</replaceable>)
-(<replaceable>start1</replaceable>, <replaceable>length1</replaceable>) OVERLAPS (<replaceable>start2</replaceable>, <replaceable>length2</replaceable>)
-</synopsis>
-    This expression yields true when two time periods (defined by their
-    endpoints) overlap, false when they do not overlap.  The endpoints
-    can be specified as pairs of dates, times, or time stamps; or as
-    a date, time, or time stamp followed by an interval.  When a pair
-    of values is provided, either the start or the end can be written
-    first; <literal>OVERLAPS</literal> automatically takes the earlier value
-    of the pair as the start.  Each time period is considered to
-    represent the half-open interval <replaceable>start</replaceable> <literal>&lt;=</literal>
-    <replaceable>time</replaceable> <literal>&lt;</literal> <replaceable>end</replaceable>, unless
-    <replaceable>start</replaceable> and <replaceable>end</replaceable> are equal in which case it
-    represents that single time instant.  This means for instance that two
-    time periods with only an endpoint in common do not overlap.
-   </para>
-
-<screen>
-SELECT (DATE '2001-02-16', DATE '2001-12-21') OVERLAPS
-       (DATE '2001-10-30', DATE '2002-10-30');
-<lineannotation>Result: </lineannotation><computeroutput>true</computeroutput>
-SELECT (DATE '2001-02-16', INTERVAL '100 days') OVERLAPS
-       (DATE '2001-10-30', DATE '2002-10-30');
-<lineannotation>Result: </lineannotation><computeroutput>false</computeroutput>
-SELECT (DATE '2001-10-29', DATE '2001-10-30') OVERLAPS
-       (DATE '2001-10-30', DATE '2001-10-31');
-<lineannotation>Result: </lineannotation><computeroutput>false</computeroutput>
-SELECT (DATE '2001-10-30', DATE '2001-10-30') OVERLAPS
-       (DATE '2001-10-30', DATE '2001-10-31');
-<lineannotation>Result: </lineannotation><computeroutput>true</computeroutput>
-</screen>
-
-  <para>
-   When adding an <type>interval</type> value to (or subtracting an
-   <type>interval</type> value from) a <type>timestamp</type>
-   or <type>timestamp with time zone</type> value, the months, days, and
-   microseconds fields of the <type>interval</type> value are handled in turn.
-   First, a nonzero months field advances or decrements the date of the
-   timestamp by the indicated number of months, keeping the day of month the
-   same unless it would be past the end of the new month, in which case the
-   last day of that month is used.  (For example, March 31 plus 1 month
-   becomes April 30, but March 31 plus 2 months becomes May 31.)
-   Then the days field advances or decrements the date of the timestamp by
-   the indicated number of days.  In both these steps the local time of day
-   is kept the same.  Finally, if there is a nonzero microseconds field, it
-   is added or subtracted literally.
-   When doing arithmetic on a <type>timestamp with time zone</type> value in
-   a time zone that recognizes DST, this means that adding or subtracting
-   (say) <literal>interval '1 day'</literal> does not necessarily have the
-   same result as adding or subtracting <literal>interval '24
-   hours'</literal>.
-   For example, with the session time zone set
-   to <literal>America/Denver</literal>:
-<screen>
-SELECT timestamp with time zone '2005-04-02 12:00:00-07' + interval '1 day';
-<lineannotation>Result: </lineannotation><computeroutput>2005-04-03 12:00:00-06</computeroutput>
-SELECT timestamp with time zone '2005-04-02 12:00:00-07' + interval '24 hours';
-<lineannotation>Result: </lineannotation><computeroutput>2005-04-03 13:00:00-06</computeroutput>
-</screen>
-   This happens because an hour was skipped due to a change in daylight saving
-   time at <literal>2005-04-03 02:00:00</literal> in time zone
-   <literal>America/Denver</literal>.
-  </para>
-
-  <para>
-   Note there can be ambiguity in the <literal>months</literal> field returned by
-   <function>age</function> because different months have different numbers of
-   days.  <productname>PostgreSQL</productname>'s approach uses the month from the
-   earlier of the two dates when calculating partial months.  For example,
-   <literal>age('2004-06-01', '2004-04-30')</literal> uses April to yield
-   <literal>1 mon 1 day</literal>, while using May would yield <literal>1 mon 2
-   days</literal> because May has 31 days, while April has only 30.
-  </para>
-
-  <para>
-   Subtraction of dates and timestamps can also be complex.  One conceptually
-   simple way to perform subtraction is to convert each value to a number
-   of seconds using <literal>EXTRACT(EPOCH FROM ...)</literal>, then subtract the
-   results; this produces the
-   number of <emphasis>seconds</emphasis> between the two values.  This will adjust
-   for the number of days in each month, timezone changes, and daylight
-   saving time adjustments.  Subtraction of date or timestamp
-   values with the <quote><literal>-</literal></quote> operator
-   returns the number of days (24-hours) and hours/minutes/seconds
-   between the values, making the same adjustments.  The <function>age</function>
-   function returns years, months, days, and hours/minutes/seconds,
-   performing field-by-field subtraction and then adjusting for negative
-   field values.  The following queries illustrate the differences in these
-   approaches.  The sample results were produced with <literal>timezone
-   = 'US/Eastern'</literal>; there is a daylight saving time change between the
-   two dates used:
-  </para>
-
-<screen>
-SELECT EXTRACT(EPOCH FROM timestamptz '2013-07-01 12:00:00') -
-       EXTRACT(EPOCH FROM timestamptz '2013-03-01 12:00:00');
-<lineannotation>Result: </lineannotation><computeroutput>10537200.000000</computeroutput>
-SELECT (EXTRACT(EPOCH FROM timestamptz '2013-07-01 12:00:00') -
-        EXTRACT(EPOCH FROM timestamptz '2013-03-01 12:00:00'))
-        / 60 / 60 / 24;
-<lineannotation>Result: </lineannotation><computeroutput>121.9583333333333333</computeroutput>
-SELECT timestamptz '2013-07-01 12:00:00' - timestamptz '2013-03-01 12:00:00';
-<lineannotation>Result: </lineannotation><computeroutput>121 days 23:00:00</computeroutput>
-SELECT age(timestamptz '2013-07-01 12:00:00', timestamptz '2013-03-01 12:00:00');
-<lineannotation>Result: </lineannotation><computeroutput>4 mons</computeroutput>
-</screen>
-
-  <sect2 id="functions-datetime-extract">
-   <title><function>EXTRACT</function>, <function>date_part</function></title>
-
-   <indexterm>
-    <primary>date_part</primary>
-   </indexterm>
-   <indexterm>
-    <primary>extract</primary>
-   </indexterm>
-
-<synopsis>
-EXTRACT(<replaceable>field</replaceable> FROM <replaceable>source</replaceable>)
-</synopsis>
-
-   <para>
-    The <function>extract</function> function retrieves subfields
-    such as year or hour from date/time values.
-    <replaceable>source</replaceable> must be a value expression of
-    type <type>timestamp</type>, <type>date</type>, <type>time</type>,
-    or <type>interval</type>.  (Timestamps and times can be with or
-    without time zone.)
-    <replaceable>field</replaceable> is an identifier or
-    string that selects what field to extract from the source value.
-    Not all fields are valid for every input data type; for example, fields
-    smaller than a day cannot be extracted from a <type>date</type>, while
-    fields of a day or more cannot be extracted from a <type>time</type>.
-    The <function>extract</function> function returns values of type
-    <type>numeric</type>.
-   </para>
-
-   <para>
-    The following are valid field names:
-
-    <!-- alphabetical -->
-    <variablelist>
-     <varlistentry>
-      <term><literal>century</literal></term>
-      <listitem>
-       <para>
-        The century; for <type>interval</type> values, the year field
-        divided by 100
-       </para>
-
-<screen>
-SELECT EXTRACT(CENTURY FROM TIMESTAMP '2000-12-16 12:21:13');
-<lineannotation>Result: </lineannotation><computeroutput>20</computeroutput>
-SELECT EXTRACT(CENTURY FROM TIMESTAMP '2001-02-16 20:38:40');
-<lineannotation>Result: </lineannotation><computeroutput>21</computeroutput>
-SELECT EXTRACT(CENTURY FROM DATE '0001-01-01 AD');
-<lineannotation>Result: </lineannotation><computeroutput>1</computeroutput>
-SELECT EXTRACT(CENTURY FROM DATE '0001-12-31 BC');
-<lineannotation>Result: </lineannotation><computeroutput>-1</computeroutput>
-SELECT EXTRACT(CENTURY FROM INTERVAL '2001 years');
-<lineannotation>Result: </lineannotation><computeroutput>20</computeroutput>
-</screen>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>day</literal></term>
-      <listitem>
-       <para>
-        The day of the month (1&ndash;31); for <type>interval</type>
-        values, the number of days
-       </para>
-
-<screen>
-SELECT EXTRACT(DAY FROM TIMESTAMP '2001-02-16 20:38:40');
-<lineannotation>Result: </lineannotation><computeroutput>16</computeroutput>
-SELECT EXTRACT(DAY FROM INTERVAL '40 days 1 minute');
-<lineannotation>Result: </lineannotation><computeroutput>40</computeroutput>
-</screen>
-
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>decade</literal></term>
-      <listitem>
-       <para>
-        The year field divided by 10
-       </para>
-
-<screen>
-SELECT EXTRACT(DECADE FROM TIMESTAMP '2001-02-16 20:38:40');
-<lineannotation>Result: </lineannotation><computeroutput>200</computeroutput>
-</screen>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>dow</literal></term>
-      <listitem>
-       <para>
-        The day of the week as Sunday (<literal>0</literal>) to
-        Saturday (<literal>6</literal>)
-       </para>
-
-<screen>
-SELECT EXTRACT(DOW FROM TIMESTAMP '2001-02-16 20:38:40');
-<lineannotation>Result: </lineannotation><computeroutput>5</computeroutput>
-</screen>
-       <para>
-        Note that <function>extract</function>'s day of the week numbering
-        differs from that of the <function>to_char(...,
-        'D')</function> function.
-       </para>
-
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>doy</literal></term>
-      <listitem>
-       <para>
-        The day of the year (1&ndash;365/366)
-       </para>
-
-<screen>
-SELECT EXTRACT(DOY FROM TIMESTAMP '2001-02-16 20:38:40');
-<lineannotation>Result: </lineannotation><computeroutput>47</computeroutput>
-</screen>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>epoch</literal></term>
-      <listitem>
-       <para>
-        For <type>timestamp with time zone</type> values, the
-        number of seconds since 1970-01-01 00:00:00 UTC (negative for
-        timestamps before that);
-        for <type>date</type> and <type>timestamp</type> values, the
-        nominal number of seconds since 1970-01-01 00:00:00,
-        without regard to timezone or daylight-savings rules;
-        for <type>interval</type> values, the total number
-        of seconds in the interval
-       </para>
-
-<screen>
-SELECT EXTRACT(EPOCH FROM TIMESTAMP WITH TIME ZONE '2001-02-16 20:38:40.12-08');
-<lineannotation>Result: </lineannotation><computeroutput>982384720.120000</computeroutput>
-SELECT EXTRACT(EPOCH FROM TIMESTAMP '2001-02-16 20:38:40.12');
-<lineannotation>Result: </lineannotation><computeroutput>982355920.120000</computeroutput>
-SELECT EXTRACT(EPOCH FROM INTERVAL '5 days 3 hours');
-<lineannotation>Result: </lineannotation><computeroutput>442800.000000</computeroutput>
-</screen>
-
-       <para>
-        You can convert an epoch value back to a <type>timestamp with time zone</type>
-        with <function>to_timestamp</function>:
-       </para>
-<screen>
-SELECT to_timestamp(982384720.12);
-<lineannotation>Result: </lineannotation><computeroutput>2001-02-17 04:38:40.12+00</computeroutput>
-</screen>
-
-       <para>
-        Beware that applying <function>to_timestamp</function> to an epoch
-        extracted from a <type>date</type> or <type>timestamp</type> value
-        could produce a misleading result: the result will effectively
-        assume that the original value had been given in UTC, which might
-        not be the case.
-       </para>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>hour</literal></term>
-      <listitem>
-       <para>
-        The hour field (0&ndash;23 in timestamps, unrestricted in
-        intervals)
-       </para>
-
-<screen>
-SELECT EXTRACT(HOUR FROM TIMESTAMP '2001-02-16 20:38:40');
-<lineannotation>Result: </lineannotation><computeroutput>20</computeroutput>
-</screen>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>isodow</literal></term>
-      <listitem>
-       <para>
-        The day of the week as Monday (<literal>1</literal>) to
-        Sunday (<literal>7</literal>)
-       </para>
-
-<screen>
-SELECT EXTRACT(ISODOW FROM TIMESTAMP '2001-02-18 20:38:40');
-<lineannotation>Result: </lineannotation><computeroutput>7</computeroutput>
-</screen>
-       <para>
-        This is identical to <literal>dow</literal> except for Sunday.  This
-        matches the <acronym>ISO</acronym> 8601 day of the week numbering.
-       </para>
-
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>isoyear</literal></term>
-      <listitem>
-       <para>
-        The <acronym>ISO</acronym> 8601 week-numbering year that the date
-        falls in
-       </para>
-
-<screen>
-SELECT EXTRACT(ISOYEAR FROM DATE '2006-01-01');
-<lineannotation>Result: </lineannotation><computeroutput>2005</computeroutput>
-SELECT EXTRACT(ISOYEAR FROM DATE '2006-01-02');
-<lineannotation>Result: </lineannotation><computeroutput>2006</computeroutput>
-</screen>
-
-       <para>
-        Each <acronym>ISO</acronym> 8601 week-numbering year begins with the
-        Monday of the week containing the 4th of January, so in early
-        January or late December the <acronym>ISO</acronym> year may be
-        different from the Gregorian year.  See the <literal>week</literal>
-        field for more information.
-       </para>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>julian</literal></term>
-      <listitem>
-       <para>
-        The <firstterm>Julian Date</firstterm> corresponding to the
-        date or timestamp.  Timestamps
-        that are not local midnight result in a fractional value.  See
-        <xref linkend="datetime-julian-dates"/> for more information.
-       </para>
-
-<screen>
-SELECT EXTRACT(JULIAN FROM DATE '2006-01-01');
-<lineannotation>Result: </lineannotation><computeroutput>2453737</computeroutput>
-SELECT EXTRACT(JULIAN FROM TIMESTAMP '2006-01-01 12:00');
-<lineannotation>Result: </lineannotation><computeroutput>2453737.50000000000000000000</computeroutput>
-</screen>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>microseconds</literal></term>
-      <listitem>
-       <para>
-        The seconds field, including fractional parts, multiplied by 1
-        000 000;  note that this includes full seconds
-       </para>
-
-<screen>
-SELECT EXTRACT(MICROSECONDS FROM TIME '17:12:28.5');
-<lineannotation>Result: </lineannotation><computeroutput>28500000</computeroutput>
-</screen>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>millennium</literal></term>
-      <listitem>
-       <para>
-        The millennium; for <type>interval</type> values, the year field
-        divided by 1000
-       </para>
-
-<screen>
-SELECT EXTRACT(MILLENNIUM FROM TIMESTAMP '2001-02-16 20:38:40');
-<lineannotation>Result: </lineannotation><computeroutput>3</computeroutput>
-SELECT EXTRACT(MILLENNIUM FROM INTERVAL '2001 years');
-<lineannotation>Result: </lineannotation><computeroutput>2</computeroutput>
-</screen>
-
-       <para>
-        Years in the 1900s are in the second millennium.
-        The third millennium started January 1, 2001.
-       </para>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>milliseconds</literal></term>
-      <listitem>
-       <para>
-        The seconds field, including fractional parts, multiplied by
-        1000.  Note that this includes full seconds.
-       </para>
-
-<screen>
-SELECT EXTRACT(MILLISECONDS FROM TIME '17:12:28.5');
-<lineannotation>Result: </lineannotation><computeroutput>28500.000</computeroutput>
-</screen>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>minute</literal></term>
-      <listitem>
-       <para>
-        The minutes field (0&ndash;59)
-       </para>
-
-<screen>
-SELECT EXTRACT(MINUTE FROM TIMESTAMP '2001-02-16 20:38:40');
-<lineannotation>Result: </lineannotation><computeroutput>38</computeroutput>
-</screen>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>month</literal></term>
-      <listitem>
-       <para>
-        The number of the month within the year (1&ndash;12);
-        for <type>interval</type> values, the number of months modulo 12
-        (0&ndash;11)
-       </para>
-
-<screen>
-SELECT EXTRACT(MONTH FROM TIMESTAMP '2001-02-16 20:38:40');
-<lineannotation>Result: </lineannotation><computeroutput>2</computeroutput>
-SELECT EXTRACT(MONTH FROM INTERVAL '2 years 3 months');
-<lineannotation>Result: </lineannotation><computeroutput>3</computeroutput>
-SELECT EXTRACT(MONTH FROM INTERVAL '2 years 13 months');
-<lineannotation>Result: </lineannotation><computeroutput>1</computeroutput>
-</screen>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>quarter</literal></term>
-      <listitem>
-       <para>
-        The quarter of the year (1&ndash;4) that the date is in;
-        for <type>interval</type> values, the month field divided by 3
-        plus 1
-       </para>
-
-<screen>
-SELECT EXTRACT(QUARTER FROM TIMESTAMP '2001-02-16 20:38:40');
-<lineannotation>Result: </lineannotation><computeroutput>1</computeroutput>
-SELECT EXTRACT(QUARTER FROM INTERVAL '1 year 6 months');
-<lineannotation>Result: </lineannotation><computeroutput>3</computeroutput>
-</screen>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>second</literal></term>
-      <listitem>
-       <para>
-        The seconds field, including any fractional seconds
-       </para>
-
-<screen>
-SELECT EXTRACT(SECOND FROM TIMESTAMP '2001-02-16 20:38:40');
-<lineannotation>Result: </lineannotation><computeroutput>40.000000</computeroutput>
-SELECT EXTRACT(SECOND FROM TIME '17:12:28.5');
-<lineannotation>Result: </lineannotation><computeroutput>28.500000</computeroutput>
-</screen>
-      </listitem>
-     </varlistentry>
-     <varlistentry>
-      <term><literal>timezone</literal></term>
-      <listitem>
-       <para>
-        The time zone offset from UTC, measured in seconds.  Positive values
-        correspond to time zones east of UTC, negative values to
-        zones west of UTC.  (Technically,
-        <productname>PostgreSQL</productname> does not use UTC because
-        leap seconds are not handled.)
-       </para>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>timezone_hour</literal></term>
-      <listitem>
-       <para>
-        The hour component of the time zone offset
-       </para>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>timezone_minute</literal></term>
-      <listitem>
-       <para>
-        The minute component of the time zone offset
-       </para>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>week</literal></term>
-      <listitem>
-       <para>
-        The number of the <acronym>ISO</acronym> 8601 week-numbering week of
-        the year.  By definition, ISO weeks start on Mondays and the first
-        week of a year contains January 4 of that year.  In other words, the
-        first Thursday of a year is in week 1 of that year.
-       </para>
-       <para>
-        In the ISO week-numbering system, it is possible for early-January
-        dates to be part of the 52nd or 53rd week of the previous year, and for
-        late-December dates to be part of the first week of the next year.
-        For example, <literal>2005-01-01</literal> is part of the 53rd week of year
-        2004, and <literal>2006-01-01</literal> is part of the 52nd week of year
-        2005, while <literal>2012-12-31</literal> is part of the first week of 2013.
-        It's recommended to use the <literal>isoyear</literal> field together with
-        <literal>week</literal> to get consistent results.
-       </para>
-
-       <para>
-        For <type>interval</type> values, the week field is simply the number
-        of integral days divided by 7.
-       </para>
-
-<screen>
-SELECT EXTRACT(WEEK FROM TIMESTAMP '2001-02-16 20:38:40');
-<lineannotation>Result: </lineannotation><computeroutput>7</computeroutput>
-SELECT EXTRACT(WEEK FROM INTERVAL '13 days 24 hours');
-<lineannotation>Result: </lineannotation><computeroutput>1</computeroutput>
-</screen>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><literal>year</literal></term>
-      <listitem>
-       <para>
-        The year field.  Keep in mind there is no <literal>0 AD</literal>, so subtracting
-        <literal>BC</literal> years from <literal>AD</literal> years should be done with care.
-       </para>
-
-<screen>
-SELECT EXTRACT(YEAR FROM TIMESTAMP '2001-02-16 20:38:40');
-<lineannotation>Result: </lineannotation><computeroutput>2001</computeroutput>
-</screen>
-      </listitem>
-     </varlistentry>
-
-    </variablelist>
-   </para>
-
-   <para>
-    When processing an <type>interval</type> value,
-    the <function>extract</function> function produces field values that
-    match the interpretation used by the interval output function.  This
-    can produce surprising results if one starts with a non-normalized
-    interval representation, for example:
-<screen>
-SELECT INTERVAL '80 minutes';
-<lineannotation>Result: </lineannotation><computeroutput>01:20:00</computeroutput>
-SELECT EXTRACT(MINUTES FROM INTERVAL '80 minutes');
-<lineannotation>Result: </lineannotation><computeroutput>20</computeroutput>
-</screen>
-   </para>
-
-   <note>
-    <para>
-     When the input value is +/-Infinity, <function>extract</function> returns
-     +/-Infinity for monotonically-increasing fields (<literal>epoch</literal>,
-     <literal>julian</literal>, <literal>year</literal>, <literal>isoyear</literal>,
-     <literal>decade</literal>, <literal>century</literal>, and <literal>millennium</literal>
-     for <type>timestamp</type> inputs; <literal>epoch</literal>, <literal>hour</literal>,
-     <literal>day</literal>, <literal>year</literal>, <literal>decade</literal>,
-     <literal>century</literal>, and <literal>millennium</literal> for
-     <type>interval</type> inputs).
-     For other fields, NULL is returned.  <productname>PostgreSQL</productname>
-     versions before 9.6 returned zero for all cases of infinite input.
-    </para>
-   </note>
-
-   <para>
-    The <function>extract</function> function is primarily intended
-    for computational processing.  For formatting date/time values for
-    display, see <xref linkend="functions-formatting"/>.
-   </para>
-
-   <para>
-    The <function>date_part</function> function is modeled on the traditional
-    <productname>Ingres</productname> equivalent to the
-    <acronym>SQL</acronym>-standard function <function>extract</function>:
-<synopsis>
-date_part('<replaceable>field</replaceable>', <replaceable>source</replaceable>)
-</synopsis>
-    Note that here the <replaceable>field</replaceable> parameter needs to
-    be a string value, not a name.  The valid field names for
-    <function>date_part</function> are the same as for
-    <function>extract</function>.
-    For historical reasons, the <function>date_part</function> function
-    returns values of type <type>double precision</type>.  This can result in
-    a loss of precision in certain uses.  Using <function>extract</function>
-    is recommended instead.
-   </para>
-
-<screen>
-SELECT date_part('day', TIMESTAMP '2001-02-16 20:38:40');
-<lineannotation>Result: </lineannotation><computeroutput>16</computeroutput>
-SELECT date_part('hour', INTERVAL '4 hours 3 minutes');
-<lineannotation>Result: </lineannotation><computeroutput>4</computeroutput>
-</screen>
-
-  </sect2>
-
-  <sect2 id="functions-datetime-trunc">
-   <title><function>date_trunc</function></title>
-
-   <indexterm>
-    <primary>date_trunc</primary>
-   </indexterm>
-
-   <para>
-    The function <function>date_trunc</function> is conceptually
-    similar to the <function>trunc</function> function for numbers.
-   </para>
-
-   <para>
-<synopsis>
-date_trunc(<replaceable>field</replaceable>, <replaceable>source</replaceable> <optional>, <replaceable>time_zone</replaceable> </optional>)
-</synopsis>
-    <replaceable>source</replaceable> is a value expression of type
-    <type>timestamp</type>, <type>timestamp with time zone</type>,
-    or <type>interval</type>.
-    (Values of type <type>date</type> and
-    <type>time</type> are cast automatically to <type>timestamp</type> or
-    <type>interval</type>, respectively.)
-    <replaceable>field</replaceable> selects to which precision to
-    truncate the input value.  The return value is likewise of type
-    <type>timestamp</type>, <type>timestamp with time zone</type>,
-    or <type>interval</type>,
-    and it has all fields that are less significant than the
-    selected one set to zero (or one, for day and month).
-   </para>
-
-   <para>
-    Valid values for <replaceable>field</replaceable> are:
-    <simplelist>
-     <member><literal>microseconds</literal></member>
-     <member><literal>milliseconds</literal></member>
-     <member><literal>second</literal></member>
-     <member><literal>minute</literal></member>
-     <member><literal>hour</literal></member>
-     <member><literal>day</literal></member>
-     <member><literal>week</literal></member>
-     <member><literal>month</literal></member>
-     <member><literal>quarter</literal></member>
-     <member><literal>year</literal></member>
-     <member><literal>decade</literal></member>
-     <member><literal>century</literal></member>
-     <member><literal>millennium</literal></member>
-    </simplelist>
-   </para>
-
-   <para>
-    When the input value is of type <type>timestamp with time zone</type>,
-    the truncation is performed with respect to a particular time zone;
-    for example, truncation to <literal>day</literal> produces a value that
-    is midnight in that zone.  By default, truncation is done with respect
-    to the current <xref linkend="guc-timezone"/> setting, but the
-    optional <replaceable>time_zone</replaceable> argument can be provided
-    to specify a different time zone.  The time zone name can be specified
-    in any of the ways described in <xref linkend="datatype-timezones"/>.
-   </para>
-
-   <para>
-    A time zone cannot be specified when processing <type>timestamp without
-    time zone</type> or <type>interval</type> inputs.  These are always
-    taken at face value.
-   </para>
-
-   <para>
-    Examples (assuming the local time zone is <literal>America/New_York</literal>):
-<screen>
-SELECT date_trunc('hour', TIMESTAMP '2001-02-16 20:38:40');
-<lineannotation>Result: </lineannotation><computeroutput>2001-02-16 20:00:00</computeroutput>
-SELECT date_trunc('year', TIMESTAMP '2001-02-16 20:38:40');
-<lineannotation>Result: </lineannotation><computeroutput>2001-01-01 00:00:00</computeroutput>
-SELECT date_trunc('day', TIMESTAMP WITH TIME ZONE '2001-02-16 20:38:40+00');
-<lineannotation>Result: </lineannotation><computeroutput>2001-02-16 00:00:00-05</computeroutput>
-SELECT date_trunc('day', TIMESTAMP WITH TIME ZONE '2001-02-16 20:38:40+00', 'Australia/Sydney');
-<lineannotation>Result: </lineannotation><computeroutput>2001-02-16 08:00:00-05</computeroutput>
-SELECT date_trunc('hour', INTERVAL '3 days 02:47:33');
-<lineannotation>Result: </lineannotation><computeroutput>3 days 02:00:00</computeroutput>
-</screen>
-   </para>
-  </sect2>
-
-  <sect2 id="functions-datetime-bin">
-   <title><function>date_bin</function></title>
-
-   <indexterm>
-    <primary>date_bin</primary>
-   </indexterm>
-
-   <para>
-    The function <function>date_bin</function> <quote>bins</quote> the input
-    timestamp into the specified interval (the <firstterm>stride</firstterm>)
-    aligned with a specified origin.
-   </para>
-
-   <para>
-<synopsis>
-date_bin(<replaceable>stride</replaceable>, <replaceable>source</replaceable>, <replaceable>origin</replaceable>)
-</synopsis>
-    <replaceable>source</replaceable> is a value expression of type
-    <type>timestamp</type> or <type>timestamp with time zone</type>.  (Values
-    of type <type>date</type> are cast automatically to
-    <type>timestamp</type>.)  <replaceable>stride</replaceable> is a value
-    expression of type <type>interval</type>.  The return value is likewise
-    of type <type>timestamp</type> or <type>timestamp with time zone</type>,
-    and it marks the beginning of the bin into which the
-    <replaceable>source</replaceable> is placed.
-   </para>
-
-   <para>
-    Examples:
-<screen>
-SELECT date_bin('15 minutes', TIMESTAMP '2020-02-11 15:44:17', TIMESTAMP '2001-01-01');
-<lineannotation>Result: </lineannotation><computeroutput>2020-02-11 15:30:00</computeroutput>
-SELECT date_bin('15 minutes', TIMESTAMP '2020-02-11 15:44:17', TIMESTAMP '2001-01-01 00:02:30');
-<lineannotation>Result: </lineannotation><computeroutput>2020-02-11 15:32:30</computeroutput>
-</screen>
-   </para>
-
-   <para>
-    In the case of full units (1 minute, 1 hour, etc.), it gives the same result as
-    the analogous <function>date_trunc</function> call, but the difference is
-    that <function>date_bin</function> can truncate to an arbitrary interval.
-   </para>
-
-   <para>
-    The <parameter>stride</parameter> interval must be greater than zero and
-    cannot contain units of month or larger.
-   </para>
-  </sect2>
-
-  <sect2 id="functions-datetime-zoneconvert">
-   <title><literal>AT TIME ZONE</literal> and <literal>AT LOCAL</literal></title>
-
-   <indexterm>
-    <primary>time zone</primary>
-    <secondary>conversion</secondary>
-   </indexterm>
-
-   <indexterm>
-    <primary>AT TIME ZONE</primary>
-   </indexterm>
-
-   <indexterm>
-    <primary>AT LOCAL</primary>
-   </indexterm>
-
-   <para>
-    The <literal>AT TIME ZONE</literal> operator converts time
-    stamp <emphasis>without</emphasis> time zone to/from
-    time stamp <emphasis>with</emphasis> time zone, and
-    <type>time with time zone</type> values to different time
-    zones. <xref linkend="functions-datetime-zoneconvert-table"/> shows its
-    variants.
-   </para>
-
-    <table id="functions-datetime-zoneconvert-table">
-     <title><literal>AT TIME ZONE</literal> and <literal>AT LOCAL</literal> Variants</title>
-     <tgroup cols="1">
-      <thead>
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         Operator
-        </para>
-        <para>
-         Description
-        </para>
-        <para>
-         Example(s)
-        </para></entry>
-       </row>
-      </thead>
-
-      <tbody>
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>timestamp without time zone</type> <literal>AT TIME ZONE</literal> <replaceable>zone</replaceable>
-         <returnvalue>timestamp with time zone</returnvalue>
-        </para>
-        <para>
-         Converts given time stamp <emphasis>without</emphasis> time zone to
-         time stamp <emphasis>with</emphasis> time zone, assuming the given
-         value is in the named time zone.
-        </para>
-        <para>
-         <literal>timestamp '2001-02-16 20:38:40' at time zone 'America/Denver'</literal>
-         <returnvalue>2001-02-17 03:38:40+00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>timestamp without time zone</type> <literal>AT LOCAL</literal>
-         <returnvalue>timestamp with time zone</returnvalue>
-        </para>
-        <para>
-         Converts given time stamp <emphasis>without</emphasis> time zone to
-         time stamp <emphasis>with</emphasis> the session's
-         <varname>TimeZone</varname> value as time zone.
-        </para>
-        <para>
-         <literal>timestamp '2001-02-16 20:38:40' at local</literal>
-         <returnvalue>2001-02-17 03:38:40+00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>timestamp with time zone</type> <literal>AT TIME ZONE</literal> <replaceable>zone</replaceable>
-         <returnvalue>timestamp without time zone</returnvalue>
-        </para>
-        <para>
-         Converts given time stamp <emphasis>with</emphasis> time zone to
-         time stamp <emphasis>without</emphasis> time zone, as the time would
-         appear in that zone.
-        </para>
-        <para>
-         <literal>timestamp with time zone '2001-02-16 20:38:40-05' at time zone 'America/Denver'</literal>
-         <returnvalue>2001-02-16 18:38:40</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>timestamp with time zone</type> <literal>AT LOCAL</literal>
-         <returnvalue>timestamp without time zone</returnvalue>
-        </para>
-        <para>
-         Converts given time stamp <emphasis>with</emphasis> time zone to
-         time stamp <emphasis>without</emphasis> time zone, as the time would
-         appear with the session's <varname>TimeZone</varname> value as time zone.
-        </para>
-        <para>
-         <literal>timestamp with time zone '2001-02-16 20:38:40-05' at local</literal>
-         <returnvalue>2001-02-16 18:38:40</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>time with time zone</type> <literal>AT TIME ZONE</literal> <replaceable>zone</replaceable>
-         <returnvalue>time with time zone</returnvalue>
-        </para>
-        <para>
-         Converts given time <emphasis>with</emphasis> time zone to a new time
-         zone.  Since no date is supplied, this uses the currently active UTC
-         offset for the named destination zone.
-        </para>
-        <para>
-         <literal>time with time zone '05:34:17-05' at time zone 'UTC'</literal>
-         <returnvalue>10:34:17+00</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>time with time zone</type> <literal>AT LOCAL</literal>
-         <returnvalue>time with time zone</returnvalue>
-        </para>
-        <para>
-         Converts given time <emphasis>with</emphasis> time zone to a new time
-         zone.  Since no date is supplied, this uses the currently active UTC
-         offset for the session's <varname>TimeZone</varname> value.
-        </para>
-        <para>
-         Assuming the session's <varname>TimeZone</varname> is set to <literal>UTC</literal>:
-        </para>
-        <para>
-         <literal>time with time zone '05:34:17-05' at local</literal>
-         <returnvalue>10:34:17+00</returnvalue>
-        </para></entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-   <para>
-    In these expressions, the desired time zone <replaceable>zone</replaceable> can be
-    specified either as a text value (e.g., <literal>'America/Los_Angeles'</literal>)
-    or as an interval (e.g., <literal>INTERVAL '-08:00'</literal>).
-    In the text case, a time zone name can be specified in any of the ways
-    described in <xref linkend="datatype-timezones"/>.
-    The interval case is only useful for zones that have fixed offsets from
-    UTC, so it is not very common in practice.
-   </para>
-
-   <para>
-    The syntax <literal>AT LOCAL</literal> may be used as shorthand for
-    <literal>AT TIME ZONE <replaceable>local</replaceable></literal>, where
-    <replaceable>local</replaceable> is the session's
-    <varname>TimeZone</varname> value.
-   </para>
-
-   <para>
-    Examples (assuming the current <xref linkend="guc-timezone"/> setting
-    is <literal>America/Los_Angeles</literal>):
-<screen>
-SELECT TIMESTAMP '2001-02-16 20:38:40' AT TIME ZONE 'America/Denver';
-<lineannotation>Result: </lineannotation><computeroutput>2001-02-16 19:38:40-08</computeroutput>
-SELECT TIMESTAMP WITH TIME ZONE '2001-02-16 20:38:40-05' AT TIME ZONE 'America/Denver';
-<lineannotation>Result: </lineannotation><computeroutput>2001-02-16 18:38:40</computeroutput>
-SELECT TIMESTAMP '2001-02-16 20:38:40' AT TIME ZONE 'Asia/Tokyo' AT TIME ZONE 'America/Chicago';
-<lineannotation>Result: </lineannotation><computeroutput>2001-02-16 05:38:40</computeroutput>
-SELECT TIMESTAMP WITH TIME ZONE '2001-02-16 20:38:40-05' AT LOCAL;
-<lineannotation>Result: </lineannotation><computeroutput>2001-02-16 17:38:40</computeroutput>
-SELECT TIMESTAMP WITH TIME ZONE '2001-02-16 20:38:40-05' AT TIME ZONE '+05';
-<lineannotation>Result: </lineannotation><computeroutput>2001-02-16 20:38:40</computeroutput>
-SELECT TIME WITH TIME ZONE '20:38:40-05' AT LOCAL;
-<lineannotation>Result: </lineannotation><computeroutput>17:38:40</computeroutput>
-</screen>
-    The first example adds a time zone to a value that lacks it, and
-    displays the value using the current <varname>TimeZone</varname>
-    setting.  The second example shifts the time stamp with time zone value
-    to the specified time zone, and returns the value without a time zone.
-    This allows storage and display of values different from the current
-    <varname>TimeZone</varname> setting.  The third example converts
-    Tokyo time to Chicago time.  The fourth example shifts the time stamp
-    with time zone value to the time zone currently specified by the
-    <varname>TimeZone</varname> setting and returns the value without a
-    time zone.  The fifth example demonstrates that the sign in a POSIX-style
-    time zone specification has the opposite meaning of the sign in an
-    ISO-8601 datetime literal, as described in <xref linkend="datatype-timezones"/>
-    and <xref linkend="datetime-appendix"/>.
-   </para>
-
-   <para>
-    The sixth example is a cautionary tale. Due to the fact that there is no
-    date associated with the input value, the conversion is made using the
-    current date of the session. Therefore, this static example may show a wrong
-    result depending on the time of the year it is viewed because
-    <literal>'America/Los_Angeles'</literal> observes Daylight Savings Time.
-   </para>
-
-   <para>
-    The function <literal><function>timezone</function>(<replaceable>zone</replaceable>,
-    <replaceable>timestamp</replaceable>)</literal> is equivalent to the SQL-conforming construct
-    <literal><replaceable>timestamp</replaceable> AT TIME ZONE
-    <replaceable>zone</replaceable></literal>.
-   </para>
-
-   <para>
-    The function <literal><function>timezone</function>(<replaceable>zone</replaceable>,
-    <replaceable>time</replaceable>)</literal> is equivalent to the SQL-conforming construct
-    <literal><replaceable>time</replaceable> AT TIME ZONE
-    <replaceable>zone</replaceable></literal>.
-   </para>
-
-   <para>
-    The function <literal><function>timezone</function>(<replaceable>timestamp</replaceable>)</literal>
-    is equivalent to the SQL-conforming construct <literal><replaceable>timestamp</replaceable>
-    AT LOCAL</literal>.
-   </para>
-
-   <para>
-    The function <literal><function>timezone</function>(<replaceable>time</replaceable>)</literal>
-    is equivalent to the SQL-conforming construct <literal><replaceable>time</replaceable>
-    AT LOCAL</literal>.
-   </para>
-  </sect2>
-
-  <sect2 id="functions-datetime-current">
-   <title>Current Date/Time</title>
-
-   <indexterm>
-    <primary>date</primary>
-    <secondary>current</secondary>
-   </indexterm>
-
-   <indexterm>
-    <primary>time</primary>
-    <secondary>current</secondary>
-   </indexterm>
-
-   <para>
-    <productname>PostgreSQL</productname> provides a number of functions
-    that return values related to the current date and time.  These
-    SQL-standard functions all return values based on the start time of
-    the current transaction:
-<synopsis>
-CURRENT_DATE
-CURRENT_TIME
-CURRENT_TIMESTAMP
-CURRENT_TIME(<replaceable>precision</replaceable>)
-CURRENT_TIMESTAMP(<replaceable>precision</replaceable>)
-LOCALTIME
-LOCALTIMESTAMP
-LOCALTIME(<replaceable>precision</replaceable>)
-LOCALTIMESTAMP(<replaceable>precision</replaceable>)
-</synopsis>
-    </para>
-
-    <para>
-     <function>CURRENT_TIME</function> and
-     <function>CURRENT_TIMESTAMP</function> deliver values with time zone;
-     <function>LOCALTIME</function> and
-     <function>LOCALTIMESTAMP</function> deliver values without time zone.
-    </para>
-
-    <para>
-     <function>CURRENT_TIME</function>,
-     <function>CURRENT_TIMESTAMP</function>,
-     <function>LOCALTIME</function>, and
-     <function>LOCALTIMESTAMP</function>
-     can optionally take
-     a precision parameter, which causes the result to be rounded
-     to that many fractional digits in the seconds field.  Without a precision parameter,
-     the result is given to the full available precision.
-    </para>
-
-   <para>
-    Some examples:
-<screen>
-SELECT CURRENT_TIME;
-<lineannotation>Result: </lineannotation><computeroutput>14:39:53.662522-05</computeroutput>
-SELECT CURRENT_DATE;
-<lineannotation>Result: </lineannotation><computeroutput>2019-12-23</computeroutput>
-SELECT CURRENT_TIMESTAMP;
-<lineannotation>Result: </lineannotation><computeroutput>2019-12-23 14:39:53.662522-05</computeroutput>
-SELECT CURRENT_TIMESTAMP(2);
-<lineannotation>Result: </lineannotation><computeroutput>2019-12-23 14:39:53.66-05</computeroutput>
-SELECT LOCALTIMESTAMP;
-<lineannotation>Result: </lineannotation><computeroutput>2019-12-23 14:39:53.662522</computeroutput>
-</screen>
-   </para>
-
-   <para>
-    Since these functions return
-    the start time of the current transaction, their values do not
-    change during the transaction. This is considered a feature:
-    the intent is to allow a single transaction to have a consistent
-    notion of the <quote>current</quote> time, so that multiple
-    modifications within the same transaction bear the same
-    time stamp.
-   </para>
-
-   <note>
-    <para>
-     Other database systems might advance these values more
-     frequently.
-    </para>
-   </note>
-
-   <para>
-    <productname>PostgreSQL</productname> also provides functions that
-    return the start time of the current statement, as well as the actual
-    current time at the instant the function is called.  The complete list
-    of non-SQL-standard time functions is:
-<synopsis>
-transaction_timestamp()
-statement_timestamp()
-clock_timestamp()
-timeofday()
-now()
-</synopsis>
-   </para>
-
-   <para>
-    <function>transaction_timestamp()</function> is equivalent to
-    <function>CURRENT_TIMESTAMP</function>, but is named to clearly reflect
-    what it returns.
-    <function>statement_timestamp()</function> returns the start time of the current
-    statement (more specifically, the time of receipt of the latest command
-    message from the client).
-    <function>statement_timestamp()</function> and <function>transaction_timestamp()</function>
-    return the same value during the first command of a transaction, but might
-    differ during subsequent commands.
-    <function>clock_timestamp()</function> returns the actual current time, and
-    therefore its value changes even within a single SQL command.
-    <function>timeofday()</function> is a historical
-    <productname>PostgreSQL</productname> function.  Like
-    <function>clock_timestamp()</function>, it returns the actual current time,
-    but as a formatted <type>text</type> string rather than a <type>timestamp
-    with time zone</type> value.
-    <function>now()</function> is a traditional <productname>PostgreSQL</productname>
-    equivalent to <function>transaction_timestamp()</function>.
-   </para>
-
-   <para>
-    All the date/time data types also accept the special literal value
-    <literal>now</literal> to specify the current date and time (again,
-    interpreted as the transaction start time).  Thus,
-    the following three all return the same result:
-<programlisting>
-SELECT CURRENT_TIMESTAMP;
-SELECT now();
-SELECT TIMESTAMP 'now';  -- but see tip below
-</programlisting>
-   </para>
-
-    <tip>
-     <para>
-      Do not use the third form when specifying a value to be evaluated later,
-      for example in a <literal>DEFAULT</literal> clause for a table column.
-      The system will convert <literal>now</literal>
-      to a <type>timestamp</type> as soon as the constant is parsed, so that when
-      the default value is needed,
-      the time of the table creation would be used!  The first two
-      forms will not be evaluated until the default value is used,
-      because they are function calls.  Thus they will give the desired
-      behavior of defaulting to the time of row insertion.
-      (See also <xref linkend="datatype-datetime-special-values"/>.)
-     </para>
-    </tip>
-  </sect2>
-
-  <sect2 id="functions-datetime-delay">
-   <title>Delaying Execution</title>
-
-   <indexterm>
-    <primary>pg_sleep</primary>
-   </indexterm>
-   <indexterm>
-    <primary>pg_sleep_for</primary>
-   </indexterm>
-   <indexterm>
-    <primary>pg_sleep_until</primary>
-   </indexterm>
-   <indexterm>
-    <primary>sleep</primary>
-   </indexterm>
-   <indexterm>
-    <primary>delay</primary>
-   </indexterm>
-
-   <para>
-    The following functions are available to delay execution of the server
-    process:
-<synopsis>
-pg_sleep ( <type>double precision</type> )
-pg_sleep_for ( <type>interval</type> )
-pg_sleep_until ( <type>timestamp with time zone</type> )
-</synopsis>
-
-    <function>pg_sleep</function> makes the current session's process
-    sleep until the given number of seconds have
-    elapsed.  Fractional-second delays can be specified.
-    <function>pg_sleep_for</function> is a convenience function to
-    allow the sleep time to be specified as an <type>interval</type>.
-    <function>pg_sleep_until</function> is a convenience function for when
-    a specific wake-up time is desired.
-    For example:
-
-<programlisting>
-SELECT pg_sleep(1.5);
-SELECT pg_sleep_for('5 minutes');
-SELECT pg_sleep_until('tomorrow 03:00');
-</programlisting>
-   </para>
-
-   <note>
-     <para>
-      The effective resolution of the sleep interval is platform-specific;
-      0.01 seconds is a common value.  The sleep delay will be at least as long
-      as specified. It might be longer depending on factors such as server load.
-      In particular, <function>pg_sleep_until</function> is not guaranteed to
-      wake up exactly at the specified time, but it will not wake up any earlier.
-     </para>
-   </note>
-
-   <warning>
-     <para>
-      Make sure that your session does not hold more locks than necessary
-      when calling <function>pg_sleep</function> or its variants.  Otherwise
-      other sessions might have to wait for your sleeping process, slowing down
-      the entire system.
-     </para>
-   </warning>
-  </sect2>
-
- </sect1>
-
-
- <sect1 id="functions-enum">
-  <title>Enum Support Functions</title>
-
-  <para>
-   For enum types (described in <xref linkend="datatype-enum"/>),
-   there are several functions that allow cleaner programming without
-   hard-coding particular values of an enum type.
-   These are listed in <xref linkend="functions-enum-table"/>. The examples
-   assume an enum type created as:
-
-<programlisting>
-CREATE TYPE rainbow AS ENUM ('red', 'orange', 'yellow', 'green', 'blue', 'purple');
-</programlisting>
-
-  </para>
-
-  <table id="functions-enum-table">
-    <title>Enum Support Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>enum_first</primary>
-        </indexterm>
-        <function>enum_first</function> ( <type>anyenum</type> )
-        <returnvalue>anyenum</returnvalue>
-       </para>
-       <para>
-        Returns the first value of the input enum type.
-       </para>
-       <para>
-        <literal>enum_first(null::rainbow)</literal>
-        <returnvalue>red</returnvalue>
-       </para></entry>
-      </row>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>enum_last</primary>
-        </indexterm>
-        <function>enum_last</function> ( <type>anyenum</type> )
-        <returnvalue>anyenum</returnvalue>
-       </para>
-       <para>
-        Returns the last value of the input enum type.
-       </para>
-       <para>
-        <literal>enum_last(null::rainbow)</literal>
-        <returnvalue>purple</returnvalue>
-       </para></entry>
-      </row>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>enum_range</primary>
-        </indexterm>
-        <function>enum_range</function> ( <type>anyenum</type> )
-        <returnvalue>anyarray</returnvalue>
-       </para>
-       <para>
-        Returns all values of the input enum type in an ordered array.
-       </para>
-       <para>
-        <literal>enum_range(null::rainbow)</literal>
-        <returnvalue>{red,orange,yellow,&zwsp;green,blue,purple}</returnvalue>
-       </para></entry>
-      </row>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>enum_range</function> ( <type>anyenum</type>, <type>anyenum</type> )
-        <returnvalue>anyarray</returnvalue>
-       </para>
-       <para>
-        Returns the range between the two given enum values, as an ordered
-        array. The values must be from the same enum type. If the first
-        parameter is null, the result will start with the first value of
-        the enum type.
-        If the second parameter is null, the result will end with the last
-        value of the enum type.
-       </para>
-       <para>
-        <literal>enum_range('orange'::rainbow, 'green'::rainbow)</literal>
-        <returnvalue>{orange,yellow,green}</returnvalue>
-       </para>
-       <para>
-        <literal>enum_range(NULL, 'green'::rainbow)</literal>
-        <returnvalue>{red,orange,&zwsp;yellow,green}</returnvalue>
-       </para>
-       <para>
-        <literal>enum_range('orange'::rainbow, NULL)</literal>
-        <returnvalue>{orange,yellow,green,&zwsp;blue,purple}</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    Notice that except for the two-argument form of <function>enum_range</function>,
-    these functions disregard the specific value passed to them; they care
-    only about its declared data type.  Either null or a specific value of
-    the type can be passed, with the same result.  It is more common to
-    apply these functions to a table column or function argument than to
-    a hardwired type name as used in the examples.
-   </para>
- </sect1>
-
- <sect1 id="functions-geometry">
-  <title>Geometric Functions and Operators</title>
-
-   <para>
-    The geometric types <type>point</type>, <type>box</type>,
-    <type>lseg</type>, <type>line</type>, <type>path</type>,
-    <type>polygon</type>, and <type>circle</type> have a large set of
-    native support functions and operators, shown in <xref
-    linkend="functions-geometry-op-table"/>, <xref
-    linkend="functions-geometry-func-table"/>, and <xref
-    linkend="functions-geometry-conv-table"/>.
-   </para>
-
-   <table id="functions-geometry-op-table">
-    <title>Geometric Operators</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Operator
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>+</literal> <type>point</type>
-        <returnvalue><replaceable>geometric_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Adds the coordinates of the second <type>point</type> to those of each
-        point of the first argument, thus performing translation.
-        Available for <type>point</type>, <type>box</type>, <type>path</type>,
-        <type>circle</type>.
-       </para>
-       <para>
-        <literal>box '(1,1),(0,0)' + point '(2,0)'</literal>
-        <returnvalue>(3,1),(2,0)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>path</type> <literal>+</literal> <type>path</type>
-        <returnvalue>path</returnvalue>
-       </para>
-       <para>
-        Concatenates two open paths (returns NULL if either path is closed).
-       </para>
-       <para>
-        <literal>path '[(0,0),(1,1)]' + path '[(2,2),(3,3),(4,4)]'</literal>
-        <returnvalue>[(0,0),(1,1),(2,2),(3,3),(4,4)]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>-</literal> <type>point</type>
-        <returnvalue><replaceable>geometric_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Subtracts the coordinates of the second <type>point</type> from those
-        of each point of the first argument, thus performing translation.
-        Available for <type>point</type>, <type>box</type>, <type>path</type>,
-        <type>circle</type>.
-       </para>
-       <para>
-        <literal>box '(1,1),(0,0)' - point '(2,0)'</literal>
-        <returnvalue>(-1,1),(-2,0)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>*</literal> <type>point</type>
-        <returnvalue><replaceable>geometric_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Multiplies each point of the first argument by the second
-        <type>point</type> (treating a point as being a complex number
-        represented by real and imaginary parts, and performing standard
-        complex multiplication).  If one interprets
-        the second <type>point</type> as a vector, this is equivalent to
-        scaling the object's size and distance from the origin by the length
-        of the vector, and rotating it counterclockwise around the origin by
-        the vector's angle from the <replaceable>x</replaceable> axis.
-        Available for <type>point</type>, <type>box</type>,<footnote
-        id="functions-geometry-rotation-fn"><para><quote>Rotating</quote> a
-        box with these operators only moves its corner points: the box is
-        still considered to have sides parallel to the axes.  Hence the box's
-        size is not preserved, as a true rotation would do.</para></footnote>
-        <type>path</type>, <type>circle</type>.
-       </para>
-       <para>
-        <literal>path '((0,0),(1,0),(1,1))' * point '(3.0,0)'</literal>
-        <returnvalue>((0,0),(3,0),(3,3))</returnvalue>
-       </para>
-       <para>
-        <literal>path '((0,0),(1,0),(1,1))' * point(cosd(45), sind(45))</literal>
-        <returnvalue>((0,0),&zwsp;(0.7071067811865475,0.7071067811865475),&zwsp;(0,1.414213562373095))</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>/</literal> <type>point</type>
-        <returnvalue><replaceable>geometric_type</replaceable></returnvalue>
-       </para>
-       <para>
-        Divides each point of the first argument by the second
-        <type>point</type> (treating a point as being a complex number
-        represented by real and imaginary parts, and performing standard
-        complex division).  If one interprets
-        the second <type>point</type> as a vector, this is equivalent to
-        scaling the object's size and distance from the origin down by the
-        length of the vector, and rotating it clockwise around the origin by
-        the vector's angle from the <replaceable>x</replaceable> axis.
-        Available for <type>point</type>, <type>box</type>,<footnoteref
-        linkend="functions-geometry-rotation-fn"/> <type>path</type>,
-        <type>circle</type>.
-       </para>
-       <para>
-        <literal>path '((0,0),(1,0),(1,1))' / point '(2.0,0)'</literal>
-        <returnvalue>((0,0),(0.5,0),(0.5,0.5))</returnvalue>
-       </para>
-       <para>
-        <literal>path '((0,0),(1,0),(1,1))' / point(cosd(45), sind(45))</literal>
-        <returnvalue>((0,0),&zwsp;(0.7071067811865476,-0.7071067811865476),&zwsp;(1.4142135623730951,0))</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>@-@</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes the total length.
-        Available for <type>lseg</type>, <type>path</type>.
-       </para>
-       <para>
-        <literal>@-@ path '[(0,0),(1,0),(1,1)]'</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>@@</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>point</returnvalue>
-       </para>
-       <para>
-        Computes the center point.
-        Available for <type>box</type>, <type>lseg</type>,
-        <type>polygon</type>, <type>circle</type>.
-       </para>
-       <para>
-        <literal>@@ box '(2,2),(0,0)'</literal>
-        <returnvalue>(1,1)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>#</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the number of points.
-        Available for <type>path</type>, <type>polygon</type>.
-       </para>
-       <para>
-        <literal># path '((1,0),(0,1),(-1,0))'</literal>
-        <returnvalue>3</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>#</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>point</returnvalue>
-       </para>
-       <para>
-        Computes the point of intersection, or NULL if there is none.
-        Available for <type>lseg</type>, <type>line</type>.
-       </para>
-       <para>
-        <literal>lseg '[(0,0),(1,1)]' # lseg '[(1,0),(0,1)]'</literal>
-        <returnvalue>(0.5,0.5)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>box</type> <literal>#</literal> <type>box</type>
-        <returnvalue>box</returnvalue>
-       </para>
-       <para>
-        Computes the intersection of two boxes, or NULL if there is none.
-       </para>
-       <para>
-        <literal>box '(2,2),(-1,-1)' # box '(1,1),(-2,-2)'</literal>
-        <returnvalue>(1,1),(-1,-1)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>##</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>point</returnvalue>
-       </para>
-       <para>
-        Computes the closest point to the first object on the second object.
-        Available for these pairs of types:
-        (<type>point</type>, <type>box</type>),
-        (<type>point</type>, <type>lseg</type>),
-        (<type>point</type>, <type>line</type>),
-        (<type>lseg</type>, <type>box</type>),
-        (<type>lseg</type>, <type>lseg</type>),
-        (<type>line</type>, <type>lseg</type>).
-       </para>
-       <para>
-        <literal>point '(0,0)' ## lseg '[(2,0),(0,2)]'</literal>
-        <returnvalue>(1,1)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>&lt;-&gt;</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes the distance between the objects.
-        Available for all seven geometric types, for all combinations
-        of <type>point</type> with another geometric type, and for
-        these additional pairs of types:
-        (<type>box</type>, <type>lseg</type>),
-        (<type>lseg</type>, <type>line</type>),
-        (<type>polygon</type>, <type>circle</type>)
-        (and the commutator cases).
-       </para>
-       <para>
-        <literal>circle '&lt;(0,0),1&gt;' &lt;-&gt; circle '&lt;(5,0),1&gt;'</literal>
-        <returnvalue>3</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>@&gt;</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does first object contain second?
-        Available for these pairs of types:
-        (<literal>box</literal>, <literal>point</literal>),
-        (<literal>box</literal>, <literal>box</literal>),
-        (<literal>path</literal>, <literal>point</literal>),
-        (<literal>polygon</literal>, <literal>point</literal>),
-        (<literal>polygon</literal>, <literal>polygon</literal>),
-        (<literal>circle</literal>, <literal>point</literal>),
-        (<literal>circle</literal>, <literal>circle</literal>).
-       </para>
-       <para>
-        <literal>circle '&lt;(0,0),2&gt;' @&gt; point '(1,1)'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>&lt;@</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is first object contained in or on second?
-        Available for these pairs of types:
-        (<literal>point</literal>, <literal>box</literal>),
-        (<literal>point</literal>, <literal>lseg</literal>),
-        (<literal>point</literal>, <literal>line</literal>),
-        (<literal>point</literal>, <literal>path</literal>),
-        (<literal>point</literal>, <literal>polygon</literal>),
-        (<literal>point</literal>, <literal>circle</literal>),
-        (<literal>box</literal>, <literal>box</literal>),
-        (<literal>lseg</literal>, <literal>box</literal>),
-        (<literal>lseg</literal>, <literal>line</literal>),
-        (<literal>polygon</literal>, <literal>polygon</literal>),
-        (<literal>circle</literal>, <literal>circle</literal>).
-       </para>
-       <para>
-        <literal>point '(1,1)' &lt;@ circle '&lt;(0,0),2&gt;'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>&amp;&amp;</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Do these objects overlap?  (One point in common makes this true.)
-        Available for <type>box</type>, <type>polygon</type>,
-        <type>circle</type>.
-       </para>
-       <para>
-        <literal>box '(1,1),(0,0)' &amp;&amp; box '(2,2),(0,0)'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>&lt;&lt;</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is first object strictly left of second?
-        Available for <type>point</type>, <type>box</type>,
-        <type>polygon</type>, <type>circle</type>.
-       </para>
-       <para>
-        <literal>circle '&lt;(0,0),1&gt;' &lt;&lt; circle '&lt;(5,0),1&gt;'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>&gt;&gt;</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is first object strictly right of second?
-        Available for <type>point</type>, <type>box</type>,
-        <type>polygon</type>, <type>circle</type>.
-       </para>
-       <para>
-        <literal>circle '&lt;(5,0),1&gt;' &gt;&gt; circle '&lt;(0,0),1&gt;'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>&amp;&lt;</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does first object not extend to the right of second?
-        Available for <type>box</type>, <type>polygon</type>,
-        <type>circle</type>.
-       </para>
-       <para>
-        <literal>box '(1,1),(0,0)' &amp;&lt; box '(2,2),(0,0)'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>&amp;&gt;</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does first object not extend to the left of second?
-        Available for <type>box</type>, <type>polygon</type>,
-        <type>circle</type>.
-       </para>
-       <para>
-        <literal>box '(3,3),(0,0)' &amp;&gt; box '(2,2),(0,0)'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>&lt;&lt;|</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is first object strictly below second?
-        Available for <type>point</type>, <type>box</type>, <type>polygon</type>,
-        <type>circle</type>.
-       </para>
-       <para>
-        <literal>box '(3,3),(0,0)' &lt;&lt;| box '(5,5),(3,4)'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>|&gt;&gt;</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is first object strictly above second?
-        Available for <type>point</type>, <type>box</type>, <type>polygon</type>,
-        <type>circle</type>.
-       </para>
-       <para>
-        <literal>box '(5,5),(3,4)' |&gt;&gt; box '(3,3),(0,0)'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>&amp;&lt;|</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does first object not extend above second?
-        Available for <type>box</type>, <type>polygon</type>,
-        <type>circle</type>.
-       </para>
-       <para>
-        <literal>box '(1,1),(0,0)' &amp;&lt;| box '(2,2),(0,0)'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>|&amp;&gt;</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does first object not extend below second?
-        Available for <type>box</type>, <type>polygon</type>,
-        <type>circle</type>.
-       </para>
-       <para>
-        <literal>box '(3,3),(0,0)' |&amp;&gt; box '(2,2),(0,0)'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>box</type> <literal>&lt;^</literal> <type>box</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is first object below second (allows edges to touch)?
-       </para>
-       <para>
-        <literal>box '((1,1),(0,0))' &lt;^ box '((2,2),(1,1))'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>box</type> <literal>&gt;^</literal> <type>box</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is first object above second (allows edges to touch)?
-       </para>
-       <para>
-        <literal>box '((2,2),(1,1))' &gt;^ box '((1,1),(0,0))'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>?#</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Do these objects intersect?
-        Available for these pairs of types:
-        (<type>box</type>, <type>box</type>),
-        (<type>lseg</type>, <type>box</type>),
-        (<type>lseg</type>, <type>lseg</type>),
-        (<type>lseg</type>, <type>line</type>),
-        (<type>line</type>, <type>box</type>),
-        (<type>line</type>, <type>line</type>),
-        (<type>path</type>, <type>path</type>).
-       </para>
-       <para>
-        <literal>lseg '[(-1,0),(1,0)]' ?# box '(2,2),(-2,-2)'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>?-</literal> <type>line</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para role="func_signature">
-        <literal>?-</literal> <type>lseg</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is line horizontal?
-       </para>
-       <para>
-        <literal>?- lseg '[(-1,0),(1,0)]'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>point</type> <literal>?-</literal> <type>point</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Are points horizontally aligned (that is, have same y coordinate)?
-       </para>
-       <para>
-        <literal>point '(1,0)' ?- point '(0,0)'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>?|</literal> <type>line</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para role="func_signature">
-        <literal>?|</literal> <type>lseg</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is line vertical?
-       </para>
-       <para>
-        <literal>?| lseg '[(-1,0),(1,0)]'</literal>
-        <returnvalue>f</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>point</type> <literal>?|</literal> <type>point</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Are points vertically aligned (that is, have same x coordinate)?
-       </para>
-       <para>
-        <literal>point '(0,1)' ?| point '(0,0)'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>line</type> <literal>?-|</literal> <type>line</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para role="func_signature">
-        <type>lseg</type> <literal>?-|</literal> <type>lseg</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Are lines perpendicular?
-       </para>
-       <para>
-        <literal>lseg '[(0,0),(0,1)]' ?-| lseg '[(0,0),(1,0)]'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>line</type> <literal>?||</literal> <type>line</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para role="func_signature">
-        <type>lseg</type> <literal>?||</literal> <type>lseg</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Are lines parallel?
-       </para>
-       <para>
-        <literal>lseg '[(-1,0),(1,0)]' ?|| lseg '[(-1,2),(1,2)]'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>geometric_type</replaceable> <literal>~=</literal> <replaceable>geometric_type</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Are these objects the same?
-        Available for <type>point</type>, <type>box</type>,
-        <type>polygon</type>, <type>circle</type>.
-       </para>
-       <para>
-        <literal>polygon '((0,0),(1,1))' ~= polygon '((1,1),(0,0))'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <caution>
-    <para>
-     Note that the <quote>same as</quote> operator, <literal>~=</literal>,
-     represents the usual notion of equality for the <type>point</type>,
-     <type>box</type>, <type>polygon</type>, and <type>circle</type> types.
-     Some of the geometric types also have an <literal>=</literal> operator, but
-     <literal>=</literal> compares for equal <emphasis>areas</emphasis> only.
-     The other scalar comparison operators (<literal>&lt;=</literal> and so
-     on), where available for these types, likewise compare areas.
-    </para>
-   </caution>
-
-   <note>
-    <para>
-     Before <productname>PostgreSQL</productname> 14, the point
-     is strictly below/above comparison operators <type>point</type>
-     <literal>&lt;&lt;|</literal> <type>point</type> and <type>point</type>
-     <literal>|&gt;&gt;</literal> <type>point</type> were respectively
-     called <literal>&lt;^</literal> and <literal>&gt;^</literal>.  These
-     names are still available, but are deprecated and will eventually be
-     removed.
-    </para>
-   </note>
-
-   <table id="functions-geometry-func-table">
-    <title>Geometric Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>area</primary>
-        </indexterm>
-        <function>area</function> ( <replaceable>geometric_type</replaceable> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes area.
-        Available for <type>box</type>, <type>path</type>, <type>circle</type>.
-        A <type>path</type> input must be closed, else NULL is returned.
-        Also, if the <type>path</type> is self-intersecting, the result may be
-        meaningless.
-       </para>
-       <para>
-        <literal>area(box '(2,2),(0,0)')</literal>
-        <returnvalue>4</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>center</primary>
-        </indexterm>
-        <function>center</function> ( <replaceable>geometric_type</replaceable> )
-        <returnvalue>point</returnvalue>
-       </para>
-       <para>
-        Computes center point.
-        Available for <type>box</type>, <type>circle</type>.
-       </para>
-       <para>
-        <literal>center(box '(1,2),(0,0)')</literal>
-        <returnvalue>(0.5,1)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>diagonal</primary>
-        </indexterm>
-        <function>diagonal</function> ( <type>box</type> )
-        <returnvalue>lseg</returnvalue>
-       </para>
-       <para>
-        Extracts box's diagonal as a line segment
-        (same as <function>lseg(box)</function>).
-       </para>
-       <para>
-        <literal>diagonal(box '(1,2),(0,0)')</literal>
-        <returnvalue>[(1,2),(0,0)]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>diameter</primary>
-        </indexterm>
-        <function>diameter</function> ( <type>circle</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes diameter of circle.
-       </para>
-       <para>
-        <literal>diameter(circle '&lt;(0,0),2&gt;')</literal>
-        <returnvalue>4</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>height</primary>
-        </indexterm>
-        <function>height</function> ( <type>box</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes vertical size of box.
-       </para>
-       <para>
-        <literal>height(box '(1,2),(0,0)')</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>isclosed</primary>
-        </indexterm>
-        <function>isclosed</function> ( <type>path</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is path closed?
-       </para>
-       <para>
-        <literal>isclosed(path '((0,0),(1,1),(2,0))')</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>isopen</primary>
-        </indexterm>
-        <function>isopen</function> ( <type>path</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is path open?
-       </para>
-       <para>
-        <literal>isopen(path '[(0,0),(1,1),(2,0)]')</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>length</primary>
-        </indexterm>
-        <function>length</function> ( <replaceable>geometric_type</replaceable> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes the total length.
-        Available for <type>lseg</type>, <type>path</type>.
-       </para>
-       <para>
-        <literal>length(path '((-1,0),(1,0))')</literal>
-        <returnvalue>4</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>npoints</primary>
-        </indexterm>
-        <function>npoints</function> ( <replaceable>geometric_type</replaceable> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the number of points.
-        Available for <type>path</type>, <type>polygon</type>.
-       </para>
-       <para>
-        <literal>npoints(path '[(0,0),(1,1),(2,0)]')</literal>
-        <returnvalue>3</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pclose</primary>
-        </indexterm>
-        <function>pclose</function> ( <type>path</type> )
-        <returnvalue>path</returnvalue>
-       </para>
-       <para>
-        Converts path to closed form.
-       </para>
-       <para>
-        <literal>pclose(path '[(0,0),(1,1),(2,0)]')</literal>
-        <returnvalue>((0,0),(1,1),(2,0))</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>popen</primary>
-        </indexterm>
-        <function>popen</function> ( <type>path</type> )
-        <returnvalue>path</returnvalue>
-       </para>
-       <para>
-        Converts path to open form.
-       </para>
-       <para>
-        <literal>popen(path '((0,0),(1,1),(2,0))')</literal>
-        <returnvalue>[(0,0),(1,1),(2,0)]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>radius</primary>
-        </indexterm>
-        <function>radius</function> ( <type>circle</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes radius of circle.
-       </para>
-       <para>
-        <literal>radius(circle '&lt;(0,0),2&gt;')</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>slope</primary>
-        </indexterm>
-        <function>slope</function> ( <type>point</type>, <type>point</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes slope of a line drawn through the two points.
-       </para>
-       <para>
-        <literal>slope(point '(0,0)', point '(2,1)')</literal>
-        <returnvalue>0.5</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>width</primary>
-        </indexterm>
-        <function>width</function> ( <type>box</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes horizontal size of box.
-       </para>
-       <para>
-        <literal>width(box '(1,2),(0,0)')</literal>
-        <returnvalue>1</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <table id="functions-geometry-conv-table">
-    <title>Geometric Type Conversion Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-     <tbody>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>box</primary>
-        </indexterm>
-        <function>box</function> ( <type>circle</type> )
-        <returnvalue>box</returnvalue>
-       </para>
-       <para>
-        Computes box inscribed within the circle.
-       </para>
-       <para>
-        <literal>box(circle '&lt;(0,0),2&gt;')</literal>
-        <returnvalue>(1.414213562373095,1.414213562373095),&zwsp;(-1.414213562373095,-1.414213562373095)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>box</function> ( <type>point</type> )
-        <returnvalue>box</returnvalue>
-       </para>
-       <para>
-        Converts point to empty box.
-       </para>
-       <para>
-        <literal>box(point '(1,0)')</literal>
-        <returnvalue>(1,0),(1,0)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>box</function> ( <type>point</type>, <type>point</type> )
-        <returnvalue>box</returnvalue>
-       </para>
-       <para>
-        Converts any two corner points to box.
-       </para>
-       <para>
-        <literal>box(point '(0,1)', point '(1,0)')</literal>
-        <returnvalue>(1,1),(0,0)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>box</function> ( <type>polygon</type> )
-        <returnvalue>box</returnvalue>
-       </para>
-       <para>
-        Computes bounding box of polygon.
-       </para>
-       <para>
-        <literal>box(polygon '((0,0),(1,1),(2,0))')</literal>
-        <returnvalue>(2,1),(0,0)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>bound_box</primary>
-        </indexterm>
-        <function>bound_box</function> ( <type>box</type>, <type>box</type> )
-        <returnvalue>box</returnvalue>
-       </para>
-       <para>
-        Computes bounding box of two boxes.
-       </para>
-       <para>
-        <literal>bound_box(box '(1,1),(0,0)', box '(4,4),(3,3)')</literal>
-        <returnvalue>(4,4),(0,0)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>circle</primary>
-        </indexterm>
-        <function>circle</function> ( <type>box</type> )
-        <returnvalue>circle</returnvalue>
-       </para>
-       <para>
-        Computes smallest circle enclosing box.
-       </para>
-       <para>
-        <literal>circle(box '(1,1),(0,0)')</literal>
-        <returnvalue>&lt;(0.5,0.5),0.7071067811865476&gt;</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>circle</function> ( <type>point</type>, <type>double precision</type> )
-        <returnvalue>circle</returnvalue>
-       </para>
-       <para>
-        Constructs circle from center and radius.
-       </para>
-       <para>
-        <literal>circle(point '(0,0)', 2.0)</literal>
-        <returnvalue>&lt;(0,0),2&gt;</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>circle</function> ( <type>polygon</type> )
-        <returnvalue>circle</returnvalue>
-       </para>
-       <para>
-        Converts polygon to circle.  The circle's center is the mean of the
-        positions of the polygon's points, and the radius is the average
-        distance of the polygon's points from that center.
-       </para>
-       <para>
-        <literal>circle(polygon '((0,0),(1,3),(2,0))')</literal>
-        <returnvalue>&lt;(1,1),1.6094757082487299&gt;</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>line</primary>
-        </indexterm>
-        <function>line</function> ( <type>point</type>, <type>point</type> )
-        <returnvalue>line</returnvalue>
-       </para>
-       <para>
-        Converts two points to the line through them.
-       </para>
-       <para>
-        <literal>line(point '(-1,0)', point '(1,0)')</literal>
-        <returnvalue>{0,-1,0}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>lseg</primary>
-        </indexterm>
-        <function>lseg</function> ( <type>box</type> )
-        <returnvalue>lseg</returnvalue>
-       </para>
-       <para>
-        Extracts box's diagonal as a line segment.
-       </para>
-       <para>
-        <literal>lseg(box '(1,0),(-1,0)')</literal>
-        <returnvalue>[(1,0),(-1,0)]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>lseg</function> ( <type>point</type>, <type>point</type> )
-        <returnvalue>lseg</returnvalue>
-       </para>
-       <para>
-        Constructs line segment from two endpoints.
-       </para>
-       <para>
-        <literal>lseg(point '(-1,0)', point '(1,0)')</literal>
-        <returnvalue>[(-1,0),(1,0)]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>path</primary>
-        </indexterm>
-        <function>path</function> ( <type>polygon</type> )
-        <returnvalue>path</returnvalue>
-       </para>
-       <para>
-        Converts polygon to a closed path with the same list of points.
-       </para>
-       <para>
-        <literal>path(polygon '((0,0),(1,1),(2,0))')</literal>
-        <returnvalue>((0,0),(1,1),(2,0))</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>point</primary>
-        </indexterm>
-        <function>point</function> ( <type>double precision</type>, <type>double precision</type> )
-        <returnvalue>point</returnvalue>
-       </para>
-       <para>
-        Constructs point from its coordinates.
-       </para>
-       <para>
-        <literal>point(23.4, -44.5)</literal>
-        <returnvalue>(23.4,-44.5)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>point</function> ( <type>box</type> )
-        <returnvalue>point</returnvalue>
-       </para>
-       <para>
-        Computes center of box.
-       </para>
-       <para>
-        <literal>point(box '(1,0),(-1,0)')</literal>
-        <returnvalue>(0,0)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>point</function> ( <type>circle</type> )
-        <returnvalue>point</returnvalue>
-       </para>
-       <para>
-        Computes center of circle.
-       </para>
-       <para>
-        <literal>point(circle '&lt;(0,0),2&gt;')</literal>
-        <returnvalue>(0,0)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>point</function> ( <type>lseg</type> )
-        <returnvalue>point</returnvalue>
-       </para>
-       <para>
-        Computes center of line segment.
-       </para>
-       <para>
-        <literal>point(lseg '[(-1,0),(1,0)]')</literal>
-        <returnvalue>(0,0)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>point</function> ( <type>polygon</type> )
-        <returnvalue>point</returnvalue>
-       </para>
-       <para>
-        Computes center of polygon (the mean of the
-        positions of the polygon's points).
-       </para>
-       <para>
-        <literal>point(polygon '((0,0),(1,1),(2,0))')</literal>
-        <returnvalue>(1,0.3333333333333333)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>polygon</primary>
-        </indexterm>
-        <function>polygon</function> ( <type>box</type> )
-        <returnvalue>polygon</returnvalue>
-       </para>
-       <para>
-        Converts box to a 4-point polygon.
-       </para>
-       <para>
-        <literal>polygon(box '(1,1),(0,0)')</literal>
-        <returnvalue>((0,0),(0,1),(1,1),(1,0))</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>polygon</function> ( <type>circle</type> )
-        <returnvalue>polygon</returnvalue>
-       </para>
-       <para>
-        Converts circle to a 12-point polygon.
-       </para>
-       <para>
-        <literal>polygon(circle '&lt;(0,0),2&gt;')</literal>
-        <returnvalue>((-2,0),&zwsp;(-1.7320508075688774,0.9999999999999999),&zwsp;(-1.0000000000000002,1.7320508075688772),&zwsp;(-1.2246063538223773e-16,2),&zwsp;(0.9999999999999996,1.7320508075688774),&zwsp;(1.732050807568877,1.0000000000000007),&zwsp;(2,2.4492127076447545e-16),&zwsp;(1.7320508075688776,-0.9999999999999994),&zwsp;(1.0000000000000009,-1.7320508075688767),&zwsp;(3.673819061467132e-16,-2),&zwsp;(-0.9999999999999987,-1.732050807568878),&zwsp;(-1.7320508075688767,-1.0000000000000009))</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>polygon</function> ( <type>integer</type>, <type>circle</type> )
-        <returnvalue>polygon</returnvalue>
-       </para>
-       <para>
-        Converts circle to an <replaceable>n</replaceable>-point polygon.
-       </para>
-       <para>
-        <literal>polygon(4, circle '&lt;(3,0),1&gt;')</literal>
-        <returnvalue>((2,0),&zwsp;(3,1),&zwsp;(4,1.2246063538223773e-16),&zwsp;(3,-1))</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>polygon</function> ( <type>path</type> )
-        <returnvalue>polygon</returnvalue>
-       </para>
-       <para>
-        Converts closed path to a polygon with the same list of points.
-       </para>
-       <para>
-        <literal>polygon(path '((0,0),(1,1),(2,0))')</literal>
-        <returnvalue>((0,0),(1,1),(2,0))</returnvalue>
-       </para></entry>
-      </row>
-
-     </tbody>
-    </tgroup>
-   </table>
-
-    <para>
-     It is possible to access the two component numbers of a <type>point</type>
-     as though the point were an array with indexes 0 and 1.  For example, if
-     <literal>t.p</literal> is a <type>point</type> column then
-     <literal>SELECT p[0] FROM t</literal> retrieves the X coordinate and
-     <literal>UPDATE t SET p[1] = ...</literal> changes the Y coordinate.
-     In the same way, a value of type <type>box</type> or <type>lseg</type> can be treated
-     as an array of two <type>point</type> values.
-    </para>
-
-  </sect1>
-
-
- <sect1 id="functions-net">
-  <title>Network Address Functions and Operators</title>
-
-  <para>
-   The IP network address types, <type>cidr</type> and <type>inet</type>,
-   support the usual comparison operators shown in
-   <xref linkend="functions-comparison-op-table"/>
-   as well as the specialized operators and functions shown in
-   <xref linkend="cidr-inet-operators-table"/> and
-   <xref linkend="cidr-inet-functions-table"/>.
-  </para>
-
-  <para>
-   Any <type>cidr</type> value can be cast to <type>inet</type> implicitly;
-   therefore, the operators and functions shown below as operating on
-   <type>inet</type> also work on <type>cidr</type> values.  (Where there are
-   separate functions for <type>inet</type> and <type>cidr</type>, it is
-   because the behavior should be different for the two cases.)
-   Also, it is permitted to cast an <type>inet</type> value
-   to <type>cidr</type>.  When this is done, any bits to the right of the
-   netmask are silently zeroed to create a valid <type>cidr</type> value.
-  </para>
-
-   <table id="cidr-inet-operators-table">
-    <title>IP Address Operators</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Operator
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>inet</type> <literal>&lt;&lt;</literal> <type>inet</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is subnet strictly contained by subnet?
-        This operator, and the next four, test for subnet inclusion.  They
-        consider only the network parts of the two addresses (ignoring any
-        bits to the right of the netmasks) and determine whether one network
-        is identical to or a subnet of the other.
-       </para>
-       <para>
-        <literal>inet '192.168.1.5' &lt;&lt; inet '192.168.1/24'</literal>
-        <returnvalue>t</returnvalue>
-       </para>
-       <para>
-        <literal>inet '192.168.0.5' &lt;&lt; inet '192.168.1/24'</literal>
-        <returnvalue>f</returnvalue>
-       </para>
-       <para>
-        <literal>inet '192.168.1/24' &lt;&lt; inet '192.168.1/24'</literal>
-        <returnvalue>f</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>inet</type> <literal>&lt;&lt;=</literal> <type>inet</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is subnet contained by or equal to subnet?
-       </para>
-       <para>
-        <literal>inet '192.168.1/24' &lt;&lt;= inet '192.168.1/24'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>inet</type> <literal>&gt;&gt;</literal> <type>inet</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does subnet strictly contain subnet?
-       </para>
-       <para>
-        <literal>inet '192.168.1/24' &gt;&gt; inet '192.168.1.5'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>inet</type> <literal>&gt;&gt;=</literal> <type>inet</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does subnet contain or equal subnet?
-       </para>
-       <para>
-        <literal>inet '192.168.1/24' &gt;&gt;= inet '192.168.1/24'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>inet</type> <literal>&amp;&amp;</literal> <type>inet</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does either subnet contain or equal the other?
-       </para>
-       <para>
-        <literal>inet '192.168.1/24' &amp;&amp; inet '192.168.1.80/28'</literal>
-        <returnvalue>t</returnvalue>
-       </para>
-       <para>
-        <literal>inet '192.168.1/24' &amp;&amp; inet '192.168.2.0/28'</literal>
-        <returnvalue>f</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>~</literal> <type>inet</type>
-        <returnvalue>inet</returnvalue>
-       </para>
-       <para>
-        Computes bitwise NOT.
-       </para>
-       <para>
-        <literal>~ inet '192.168.1.6'</literal>
-        <returnvalue>63.87.254.249</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>inet</type> <literal>&amp;</literal> <type>inet</type>
-        <returnvalue>inet</returnvalue>
-       </para>
-       <para>
-        Computes bitwise AND.
-       </para>
-       <para>
-        <literal>inet '192.168.1.6' &amp; inet '0.0.0.255'</literal>
-        <returnvalue>0.0.0.6</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>inet</type> <literal>|</literal> <type>inet</type>
-        <returnvalue>inet</returnvalue>
-       </para>
-       <para>
-        Computes bitwise OR.
-       </para>
-       <para>
-        <literal>inet '192.168.1.6' | inet '0.0.0.255'</literal>
-        <returnvalue>192.168.1.255</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>inet</type> <literal>+</literal> <type>bigint</type>
-        <returnvalue>inet</returnvalue>
-       </para>
-       <para>
-        Adds an offset to an address.
-       </para>
-       <para>
-        <literal>inet '192.168.1.6' + 25</literal>
-        <returnvalue>192.168.1.31</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>bigint</type> <literal>+</literal> <type>inet</type>
-        <returnvalue>inet</returnvalue>
-       </para>
-       <para>
-        Adds an offset to an address.
-       </para>
-       <para>
-        <literal>200 + inet '::ffff:fff0:1'</literal>
-        <returnvalue>::ffff:255.240.0.201</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>inet</type> <literal>-</literal> <type>bigint</type>
-        <returnvalue>inet</returnvalue>
-       </para>
-       <para>
-        Subtracts an offset from an address.
-       </para>
-       <para>
-        <literal>inet '192.168.1.43' - 36</literal>
-        <returnvalue>192.168.1.7</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>inet</type> <literal>-</literal> <type>inet</type>
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Computes the difference of two addresses.
-       </para>
-       <para>
-        <literal>inet '192.168.1.43' - inet '192.168.1.19'</literal>
-        <returnvalue>24</returnvalue>
-       </para>
-       <para>
-        <literal>inet '::1' - inet '::ffff:1'</literal>
-        <returnvalue>-4294901760</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <table id="cidr-inet-functions-table">
-    <title>IP Address Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>abbrev</primary>
-        </indexterm>
-        <function>abbrev</function> ( <type>inet</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Creates an abbreviated display format as text.
-        (The result is the same as the <type>inet</type> output function
-        produces; it is <quote>abbreviated</quote> only in comparison to the
-        result of an explicit cast to <type>text</type>, which for historical
-        reasons will never suppress the netmask part.)
-       </para>
-       <para>
-        <literal>abbrev(inet '10.1.0.0/32')</literal>
-        <returnvalue>10.1.0.0</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>abbrev</function> ( <type>cidr</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Creates an abbreviated display format as text.
-        (The abbreviation consists of dropping all-zero octets to the right
-        of the netmask; more examples are in
-        <xref linkend="datatype-net-cidr-table"/>.)
-       </para>
-       <para>
-        <literal>abbrev(cidr '10.1.0.0/16')</literal>
-        <returnvalue>10.1/16</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>broadcast</primary>
-        </indexterm>
-        <function>broadcast</function> ( <type>inet</type> )
-        <returnvalue>inet</returnvalue>
-       </para>
-       <para>
-        Computes the broadcast address for the address's network.
-       </para>
-       <para>
-        <literal>broadcast(inet '192.168.1.5/24')</literal>
-        <returnvalue>192.168.1.255/24</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>family</primary>
-        </indexterm>
-        <function>family</function> ( <type>inet</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the address's family: <literal>4</literal> for IPv4,
-        <literal>6</literal> for IPv6.
-       </para>
-       <para>
-        <literal>family(inet '::1')</literal>
-        <returnvalue>6</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>host</primary>
-        </indexterm>
-        <function>host</function> ( <type>inet</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the IP address as text, ignoring the netmask.
-       </para>
-       <para>
-        <literal>host(inet '192.168.1.0/24')</literal>
-        <returnvalue>192.168.1.0</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>hostmask</primary>
-        </indexterm>
-        <function>hostmask</function> ( <type>inet</type> )
-        <returnvalue>inet</returnvalue>
-       </para>
-       <para>
-        Computes the host mask for the address's network.
-       </para>
-       <para>
-        <literal>hostmask(inet '192.168.23.20/30')</literal>
-        <returnvalue>0.0.0.3</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>inet_merge</primary>
-        </indexterm>
-        <function>inet_merge</function> ( <type>inet</type>, <type>inet</type> )
-        <returnvalue>cidr</returnvalue>
-       </para>
-       <para>
-        Computes the smallest network that includes both of the given networks.
-       </para>
-       <para>
-        <literal>inet_merge(inet '192.168.1.5/24', inet '192.168.2.5/24')</literal>
-        <returnvalue>192.168.0.0/22</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>inet_same_family</primary>
-        </indexterm>
-        <function>inet_same_family</function> ( <type>inet</type>, <type>inet</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Tests whether the addresses belong to the same IP family.
-       </para>
-       <para>
-        <literal>inet_same_family(inet '192.168.1.5/24', inet '::1')</literal>
-        <returnvalue>f</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>masklen</primary>
-        </indexterm>
-        <function>masklen</function> ( <type>inet</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the netmask length in bits.
-       </para>
-       <para>
-        <literal>masklen(inet '192.168.1.5/24')</literal>
-        <returnvalue>24</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>netmask</primary>
-        </indexterm>
-        <function>netmask</function> ( <type>inet</type> )
-        <returnvalue>inet</returnvalue>
-       </para>
-       <para>
-        Computes the network mask for the address's network.
-       </para>
-       <para>
-        <literal>netmask(inet '192.168.1.5/24')</literal>
-        <returnvalue>255.255.255.0</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>network</primary>
-        </indexterm>
-        <function>network</function> ( <type>inet</type> )
-        <returnvalue>cidr</returnvalue>
-       </para>
-       <para>
-        Returns the network part of the address, zeroing out
-        whatever is to the right of the netmask.
-        (This is equivalent to casting the value to <type>cidr</type>.)
-       </para>
-       <para>
-        <literal>network(inet '192.168.1.5/24')</literal>
-        <returnvalue>192.168.1.0/24</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>set_masklen</primary>
-        </indexterm>
-        <function>set_masklen</function> ( <type>inet</type>, <type>integer</type> )
-        <returnvalue>inet</returnvalue>
-       </para>
-       <para>
-        Sets the netmask length for an <type>inet</type> value.
-        The address part does not change.
-       </para>
-       <para>
-        <literal>set_masklen(inet '192.168.1.5/24', 16)</literal>
-        <returnvalue>192.168.1.5/16</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>set_masklen</function> ( <type>cidr</type>, <type>integer</type> )
-        <returnvalue>cidr</returnvalue>
-       </para>
-       <para>
-        Sets the netmask length for a <type>cidr</type> value.
-        Address bits to the right of the new netmask are set to zero.
-       </para>
-       <para>
-        <literal>set_masklen(cidr '192.168.1.0/24', 16)</literal>
-        <returnvalue>192.168.0.0/16</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>text</primary>
-        </indexterm>
-        <function>text</function> ( <type>inet</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the unabbreviated IP address and netmask length as text.
-        (This has the same result as an explicit cast to <type>text</type>.)
-       </para>
-       <para>
-        <literal>text(inet '192.168.1.5')</literal>
-        <returnvalue>192.168.1.5/32</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <tip>
-   <para>
-    The <function>abbrev</function>, <function>host</function>,
-    and <function>text</function> functions are primarily intended to offer
-    alternative display formats for IP addresses.
-   </para>
-  </tip>
-
-  <para>
-   The MAC address types, <type>macaddr</type> and <type>macaddr8</type>,
-   support the usual comparison operators shown in
-   <xref linkend="functions-comparison-op-table"/>
-   as well as the specialized functions shown in
-   <xref linkend="macaddr-functions-table"/>.
-   In addition, they support the bitwise logical operators
-   <literal>~</literal>, <literal>&amp;</literal> and <literal>|</literal>
-   (NOT, AND and OR), just as shown above for IP addresses.
-  </para>
-
-   <table id="macaddr-functions-table">
-    <title>MAC Address Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>trunc</primary>
-        </indexterm>
-        <function>trunc</function> ( <type>macaddr</type> )
-        <returnvalue>macaddr</returnvalue>
-       </para>
-       <para>
-        Sets the last 3 bytes of the address to zero.  The remaining prefix
-        can be associated with a particular manufacturer (using data not
-        included in <productname>PostgreSQL</productname>).
-       </para>
-       <para>
-        <literal>trunc(macaddr '12:34:56:78:90:ab')</literal>
-        <returnvalue>12:34:56:00:00:00</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>trunc</function> ( <type>macaddr8</type> )
-        <returnvalue>macaddr8</returnvalue>
-       </para>
-       <para>
-        Sets the last 5 bytes of the address to zero.  The remaining prefix
-        can be associated with a particular manufacturer (using data not
-        included in <productname>PostgreSQL</productname>).
-       </para>
-       <para>
-        <literal>trunc(macaddr8 '12:34:56:78:90:ab:cd:ef')</literal>
-        <returnvalue>12:34:56:00:00:00:00:00</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>macaddr8_set7bit</primary>
-        </indexterm>
-        <function>macaddr8_set7bit</function> ( <type>macaddr8</type> )
-        <returnvalue>macaddr8</returnvalue>
-       </para>
-       <para>
-        Sets the 7th bit of the address to one, creating what is known as
-        modified EUI-64, for inclusion in an IPv6 address.
-       </para>
-       <para>
-        <literal>macaddr8_set7bit(macaddr8 '00:34:56:ab:cd:ef')</literal>
-        <returnvalue>02:34:56:ff:fe:ab:cd:ef</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  </sect1>
-
-
- <sect1 id="functions-textsearch">
-  <title>Text Search Functions and Operators</title>
-
-   <indexterm zone="datatype-textsearch">
-    <primary>full text search</primary>
-    <secondary>functions and operators</secondary>
-   </indexterm>
-
-   <indexterm zone="datatype-textsearch">
-    <primary>text search</primary>
-    <secondary>functions and operators</secondary>
-   </indexterm>
-
-  <para>
-   <xref linkend="textsearch-operators-table"/>,
-   <xref linkend="textsearch-functions-table"/> and
-   <xref linkend="textsearch-functions-debug-table"/>
-   summarize the functions and operators that are provided
-   for full text searching.  See <xref linkend="textsearch"/> for a detailed
-   explanation of <productname>PostgreSQL</productname>'s text search
-   facility.
-  </para>
-
-   <table id="textsearch-operators-table">
-    <title>Text Search Operators</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Operator
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>tsvector</type> <literal>@@</literal> <type>tsquery</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para role="func_signature">
-        <type>tsquery</type> <literal>@@</literal> <type>tsvector</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does <type>tsvector</type> match <type>tsquery</type>?
-        (The arguments can be given in either order.)
-       </para>
-       <para>
-        <literal>to_tsvector('fat cats ate rats') @@ to_tsquery('cat &amp; rat')</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>text</type> <literal>@@</literal> <type>tsquery</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does text string, after implicit invocation
-        of <function>to_tsvector()</function>, match <type>tsquery</type>?
-       </para>
-       <para>
-        <literal>'fat cats ate rats' @@ to_tsquery('cat &amp; rat')</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>tsvector</type> <literal>||</literal> <type>tsvector</type>
-        <returnvalue>tsvector</returnvalue>
-       </para>
-       <para>
-        Concatenates two <type>tsvector</type>s.  If both inputs contain
-        lexeme positions, the second input's positions are adjusted
-        accordingly.
-       </para>
-       <para>
-        <literal>'a:1 b:2'::tsvector || 'c:1 d:2 b:3'::tsvector</literal>
-        <returnvalue>'a':1 'b':2,5 'c':3 'd':4</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>tsquery</type> <literal>&amp;&amp;</literal> <type>tsquery</type>
-        <returnvalue>tsquery</returnvalue>
-       </para>
-       <para>
-        ANDs two <type>tsquery</type>s together, producing a query that
-        matches documents that match both input queries.
-       </para>
-       <para>
-        <literal>'fat | rat'::tsquery &amp;&amp; 'cat'::tsquery</literal>
-        <returnvalue>( 'fat' | 'rat' ) &amp; 'cat'</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>tsquery</type> <literal>||</literal> <type>tsquery</type>
-        <returnvalue>tsquery</returnvalue>
-       </para>
-       <para>
-        ORs two <type>tsquery</type>s together, producing a query that
-        matches documents that match either input query.
-       </para>
-       <para>
-        <literal>'fat | rat'::tsquery || 'cat'::tsquery</literal>
-        <returnvalue>'fat' | 'rat' | 'cat'</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>!!</literal> <type>tsquery</type>
-        <returnvalue>tsquery</returnvalue>
-       </para>
-       <para>
-        Negates a <type>tsquery</type>, producing a query that matches
-        documents that do not match the input query.
-       </para>
-       <para>
-        <literal>!! 'cat'::tsquery</literal>
-        <returnvalue>!'cat'</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>tsquery</type> <literal>&lt;-&gt;</literal> <type>tsquery</type>
-        <returnvalue>tsquery</returnvalue>
-       </para>
-       <para>
-        Constructs a phrase query, which matches if the two input queries
-        match at successive lexemes.
-       </para>
-       <para>
-        <literal>to_tsquery('fat') &lt;-&gt; to_tsquery('rat')</literal>
-        <returnvalue>'fat' &lt;-&gt; 'rat'</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>tsquery</type> <literal>@&gt;</literal> <type>tsquery</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does first <type>tsquery</type> contain the second?  (This considers
-        only whether all the lexemes appearing in one query appear in the
-        other, ignoring the combining operators.)
-       </para>
-       <para>
-        <literal>'cat'::tsquery @&gt; 'cat &amp; rat'::tsquery</literal>
-        <returnvalue>f</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>tsquery</type> <literal>&lt;@</literal> <type>tsquery</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is first <type>tsquery</type> contained in the second?  (This
-        considers only whether all the lexemes appearing in one query appear
-        in the other, ignoring the combining operators.)
-       </para>
-       <para>
-        <literal>'cat'::tsquery &lt;@ 'cat &amp; rat'::tsquery</literal>
-        <returnvalue>t</returnvalue>
-       </para>
-       <para>
-        <literal>'cat'::tsquery &lt;@ '!cat &amp; rat'::tsquery</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-    <para>
-     In addition to these specialized operators, the usual comparison
-     operators shown in <xref linkend="functions-comparison-op-table"/> are
-     available for types <type>tsvector</type> and <type>tsquery</type>.
-     These are not very
-     useful for text searching but allow, for example, unique indexes to be
-     built on columns of these types.
-    </para>
-
-   <table id="textsearch-functions-table">
-    <title>Text Search Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_to_tsvector</primary>
-        </indexterm>
-        <function>array_to_tsvector</function> ( <type>text[]</type> )
-        <returnvalue>tsvector</returnvalue>
-       </para>
-       <para>
-        Converts an array of text strings to a <type>tsvector</type>.
-        The given strings are used as lexemes as-is, without further
-        processing.  Array elements must not be empty strings
-        or <literal>NULL</literal>.
-       </para>
-       <para>
-        <literal>array_to_tsvector('{fat,cat,rat}'::text[])</literal>
-        <returnvalue>'cat' 'fat' 'rat'</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>get_current_ts_config</primary>
-        </indexterm>
-        <function>get_current_ts_config</function> ( )
-        <returnvalue>regconfig</returnvalue>
-       </para>
-       <para>
-        Returns the OID of the current default text search configuration
-        (as set by <xref linkend="guc-default-text-search-config"/>).
-       </para>
-       <para>
-        <literal>get_current_ts_config()</literal>
-        <returnvalue>english</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>length</primary>
-        </indexterm>
-        <function>length</function> ( <type>tsvector</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the number of lexemes in the <type>tsvector</type>.
-       </para>
-       <para>
-        <literal>length('fat:2,4 cat:3 rat:5A'::tsvector)</literal>
-        <returnvalue>3</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>numnode</primary>
-        </indexterm>
-        <function>numnode</function> ( <type>tsquery</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the number of lexemes plus operators in
-        the <type>tsquery</type>.
-       </para>
-       <para>
-        <literal>numnode('(fat &amp; rat) | cat'::tsquery)</literal>
-        <returnvalue>5</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>plainto_tsquery</primary>
-        </indexterm>
-        <function>plainto_tsquery</function> (
-        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
-        <parameter>query</parameter> <type>text</type> )
-        <returnvalue>tsquery</returnvalue>
-       </para>
-       <para>
-        Converts text to a <type>tsquery</type>, normalizing words according to
-        the specified or default configuration.  Any punctuation in the string
-        is ignored (it does not determine query operators).  The resulting
-        query matches documents containing all non-stopwords in the text.
-       </para>
-       <para>
-        <literal>plainto_tsquery('english', 'The Fat Rats')</literal>
-        <returnvalue>'fat' &amp; 'rat'</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>phraseto_tsquery</primary>
-        </indexterm>
-        <function>phraseto_tsquery</function> (
-        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
-        <parameter>query</parameter> <type>text</type> )
-        <returnvalue>tsquery</returnvalue>
-       </para>
-       <para>
-        Converts text to a <type>tsquery</type>, normalizing words according to
-        the specified or default configuration.  Any punctuation in the string
-        is ignored (it does not determine query operators).  The resulting
-        query matches phrases containing all non-stopwords in the text.
-       </para>
-       <para>
-        <literal>phraseto_tsquery('english', 'The Fat Rats')</literal>
-        <returnvalue>'fat' &lt;-&gt; 'rat'</returnvalue>
-       </para>
-       <para>
-        <literal>phraseto_tsquery('english', 'The Cat and Rats')</literal>
-        <returnvalue>'cat' &lt;2&gt; 'rat'</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>websearch_to_tsquery</primary>
-        </indexterm>
-        <function>websearch_to_tsquery</function> (
-        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
-        <parameter>query</parameter> <type>text</type> )
-        <returnvalue>tsquery</returnvalue>
-       </para>
-       <para>
-        Converts text to a <type>tsquery</type>, normalizing words according
-        to the specified or default configuration.  Quoted word sequences are
-        converted to phrase tests.  The word <quote>or</quote> is understood
-        as producing an OR operator, and a dash produces a NOT operator;
-        other punctuation is ignored.
-        This approximates the behavior of some common web search tools.
-       </para>
-       <para>
-        <literal>websearch_to_tsquery('english', '"fat rat" or cat dog')</literal>
-        <returnvalue>'fat' &lt;-&gt; 'rat' | 'cat' &amp; 'dog'</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>querytree</primary>
-        </indexterm>
-        <function>querytree</function> ( <type>tsquery</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Produces a representation of the indexable portion of
-        a <type>tsquery</type>.  A result that is empty or
-        just <literal>T</literal> indicates a non-indexable query.
-       </para>
-       <para>
-        <literal>querytree('foo &amp; ! bar'::tsquery)</literal>
-        <returnvalue>'foo'</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>setweight</primary>
-        </indexterm>
-        <function>setweight</function> ( <parameter>vector</parameter> <type>tsvector</type>, <parameter>weight</parameter> <type>"char"</type> )
-        <returnvalue>tsvector</returnvalue>
-       </para>
-       <para>
-        Assigns the specified <parameter>weight</parameter> to each element
-        of the <parameter>vector</parameter>.
-       </para>
-       <para>
-        <literal>setweight('fat:2,4 cat:3 rat:5B'::tsvector, 'A')</literal>
-        <returnvalue>'cat':3A 'fat':2A,4A 'rat':5A</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>setweight</primary>
-         <secondary>setweight for specific lexeme(s)</secondary>
-        </indexterm>
-        <function>setweight</function> ( <parameter>vector</parameter> <type>tsvector</type>, <parameter>weight</parameter> <type>"char"</type>, <parameter>lexemes</parameter> <type>text[]</type> )
-        <returnvalue>tsvector</returnvalue>
-       </para>
-       <para>
-        Assigns the specified <parameter>weight</parameter> to elements
-        of the <parameter>vector</parameter> that are listed
-        in <parameter>lexemes</parameter>.
-        The strings in <parameter>lexemes</parameter> are taken as lexemes
-        as-is, without further processing.  Strings that do not match any
-        lexeme in <parameter>vector</parameter> are ignored.
-       </para>
-       <para>
-        <literal>setweight('fat:2,4 cat:3 rat:5,6B'::tsvector, 'A', '{cat,rat}')</literal>
-        <returnvalue>'cat':3A 'fat':2,4 'rat':5A,6A</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>strip</primary>
-        </indexterm>
-        <function>strip</function> ( <type>tsvector</type> )
-        <returnvalue>tsvector</returnvalue>
-       </para>
-       <para>
-        Removes positions and weights from the <type>tsvector</type>.
-       </para>
-       <para>
-        <literal>strip('fat:2,4 cat:3 rat:5A'::tsvector)</literal>
-        <returnvalue>'cat' 'fat' 'rat'</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_tsquery</primary>
-        </indexterm>
-        <function>to_tsquery</function> (
-        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
-        <parameter>query</parameter> <type>text</type> )
-        <returnvalue>tsquery</returnvalue>
-       </para>
-       <para>
-        Converts text to a <type>tsquery</type>, normalizing words according to
-        the specified or default configuration.  The words must be combined
-        by valid <type>tsquery</type> operators.
-       </para>
-       <para>
-        <literal>to_tsquery('english', 'The &amp; Fat &amp; Rats')</literal>
-        <returnvalue>'fat' &amp; 'rat'</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_tsvector</primary>
-        </indexterm>
-        <function>to_tsvector</function> (
-        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
-         <parameter>document</parameter> <type>text</type> )
-        <returnvalue>tsvector</returnvalue>
-       </para>
-       <para>
-        Converts text to a <type>tsvector</type>, normalizing words according
-        to the specified or default configuration.  Position information is
-        included in the result.
-       </para>
-       <para>
-        <literal>to_tsvector('english', 'The Fat Rats')</literal>
-        <returnvalue>'fat':2 'rat':3</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>to_tsvector</function> (
-        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
-        <parameter>document</parameter> <type>json</type> )
-        <returnvalue>tsvector</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>to_tsvector</function> (
-        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
-        <parameter>document</parameter> <type>jsonb</type> )
-        <returnvalue>tsvector</returnvalue>
-       </para>
-       <para>
-        Converts each string value in the JSON document to
-        a <type>tsvector</type>, normalizing words according to the specified
-        or default configuration.  The results are then concatenated in
-        document order to produce the output.  Position information is
-        generated as though one stopword exists between each pair of string
-        values.  (Beware that <quote>document order</quote> of the fields of a
-        JSON object is implementation-dependent when the input
-        is <type>jsonb</type>; observe the difference in the examples.)
-       </para>
-       <para>
-        <literal>to_tsvector('english', '{"aa": "The Fat Rats", "b": "dog"}'::json)</literal>
-        <returnvalue>'dog':5 'fat':2 'rat':3</returnvalue>
-       </para>
-       <para>
-        <literal>to_tsvector('english', '{"aa": "The Fat Rats", "b": "dog"}'::jsonb)</literal>
-        <returnvalue>'dog':1 'fat':4 'rat':5</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_to_tsvector</primary>
-        </indexterm>
-        <function>json_to_tsvector</function> (
-        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
-        <parameter>document</parameter> <type>json</type>,
-        <parameter>filter</parameter> <type>jsonb</type> )
-        <returnvalue>tsvector</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_to_tsvector</primary>
-        </indexterm>
-        <function>jsonb_to_tsvector</function> (
-        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
-        <parameter>document</parameter> <type>jsonb</type>,
-        <parameter>filter</parameter> <type>jsonb</type> )
-        <returnvalue>tsvector</returnvalue>
-       </para>
-       <para>
-        Selects each item in the JSON document that is requested by
-        the <parameter>filter</parameter> and converts each one to
-        a <type>tsvector</type>, normalizing words according to the specified
-        or default configuration.  The results are then concatenated in
-        document order to produce the output.  Position information is
-        generated as though one stopword exists between each pair of selected
-        items.  (Beware that <quote>document order</quote> of the fields of a
-        JSON object is implementation-dependent when the input
-        is <type>jsonb</type>.)
-        The <parameter>filter</parameter> must be a <type>jsonb</type>
-        array containing zero or more of these keywords:
-        <literal>"string"</literal> (to include all string values),
-        <literal>"numeric"</literal> (to include all numeric values),
-        <literal>"boolean"</literal> (to include all boolean values),
-        <literal>"key"</literal> (to include all keys), or
-        <literal>"all"</literal> (to include all the above).
-        As a special case, the <parameter>filter</parameter> can also be a
-        simple JSON value that is one of these keywords.
-       </para>
-       <para>
-        <literal>json_to_tsvector('english', '{"a": "The Fat Rats", "b": 123}'::json, '["string", "numeric"]')</literal>
-        <returnvalue>'123':5 'fat':2 'rat':3</returnvalue>
-       </para>
-       <para>
-        <literal>json_to_tsvector('english', '{"cat": "The Fat Rats", "dog": 123}'::json, '"all"')</literal>
-        <returnvalue>'123':9 'cat':1 'dog':7 'fat':4 'rat':5</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>ts_delete</primary>
-        </indexterm>
-        <function>ts_delete</function> ( <parameter>vector</parameter> <type>tsvector</type>, <parameter>lexeme</parameter> <type>text</type> )
-        <returnvalue>tsvector</returnvalue>
-       </para>
-       <para>
-        Removes any occurrence of the given <parameter>lexeme</parameter>
-        from the <parameter>vector</parameter>.
-        The <parameter>lexeme</parameter> string is treated as a lexeme as-is,
-        without further processing.
-       </para>
-       <para>
-        <literal>ts_delete('fat:2,4 cat:3 rat:5A'::tsvector, 'fat')</literal>
-        <returnvalue>'cat':3 'rat':5A</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>ts_delete</function> ( <parameter>vector</parameter> <type>tsvector</type>, <parameter>lexemes</parameter> <type>text[]</type> )
-        <returnvalue>tsvector</returnvalue>
-       </para>
-       <para>
-        Removes any occurrences of the lexemes
-        in <parameter>lexemes</parameter>
-        from the <parameter>vector</parameter>.
-        The strings in <parameter>lexemes</parameter> are taken as lexemes
-        as-is, without further processing.  Strings that do not match any
-        lexeme in <parameter>vector</parameter> are ignored.
-       </para>
-       <para>
-        <literal>ts_delete('fat:2,4 cat:3 rat:5A'::tsvector, ARRAY['fat','rat'])</literal>
-        <returnvalue>'cat':3</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>ts_filter</primary>
-        </indexterm>
-        <function>ts_filter</function> ( <parameter>vector</parameter> <type>tsvector</type>, <parameter>weights</parameter> <type>"char"[]</type> )
-        <returnvalue>tsvector</returnvalue>
-       </para>
-       <para>
-        Selects only elements with the given <parameter>weights</parameter>
-        from the <parameter>vector</parameter>.
-       </para>
-       <para>
-        <literal>ts_filter('fat:2,4 cat:3b,7c rat:5A'::tsvector, '{a,b}')</literal>
-        <returnvalue>'cat':3B 'rat':5A</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>ts_headline</primary>
-        </indexterm>
-        <function>ts_headline</function> (
-        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
-        <parameter>document</parameter> <type>text</type>,
-        <parameter>query</parameter> <type>tsquery</type>
-        <optional>, <parameter>options</parameter> <type>text</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Displays, in an abbreviated form, the match(es) for
-        the <parameter>query</parameter> in
-        the <parameter>document</parameter>, which must be raw text not
-        a <type>tsvector</type>.  Words in the document are normalized
-        according to the specified or default configuration before matching to
-        the query.  Use of this function is discussed in
-        <xref linkend="textsearch-headline"/>, which also describes the
-        available <parameter>options</parameter>.
-       </para>
-       <para>
-        <literal>ts_headline('The fat cat ate the rat.', 'cat')</literal>
-        <returnvalue>The fat &lt;b&gt;cat&lt;/b&gt; ate the rat.</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>ts_headline</function> (
-        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
-        <parameter>document</parameter> <type>json</type>,
-        <parameter>query</parameter> <type>tsquery</type>
-        <optional>, <parameter>options</parameter> <type>text</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>ts_headline</function> (
-        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
-        <parameter>document</parameter> <type>jsonb</type>,
-        <parameter>query</parameter> <type>tsquery</type>
-        <optional>, <parameter>options</parameter> <type>text</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Displays, in an abbreviated form, match(es) for
-        the <parameter>query</parameter> that occur in string values
-        within the JSON <parameter>document</parameter>.
-        See <xref linkend="textsearch-headline"/> for more details.
-       </para>
-       <para>
-        <literal>ts_headline('{"cat":"raining cats and dogs"}'::jsonb, 'cat')</literal>
-        <returnvalue>{"cat": "raining &lt;b&gt;cats&lt;/b&gt; and dogs"}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>ts_rank</primary>
-        </indexterm>
-        <function>ts_rank</function> (
-        <optional> <parameter>weights</parameter> <type>real[]</type>, </optional>
-        <parameter>vector</parameter> <type>tsvector</type>,
-        <parameter>query</parameter> <type>tsquery</type>
-        <optional>, <parameter>normalization</parameter> <type>integer</type> </optional> )
-        <returnvalue>real</returnvalue>
-       </para>
-       <para>
-        Computes a score showing how well
-        the <parameter>vector</parameter> matches
-        the <parameter>query</parameter>.  See
-        <xref linkend="textsearch-ranking"/> for details.
-       </para>
-       <para>
-        <literal>ts_rank(to_tsvector('raining cats and dogs'), 'cat')</literal>
-        <returnvalue>0.06079271</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>ts_rank_cd</primary>
-        </indexterm>
-        <function>ts_rank_cd</function> (
-        <optional> <parameter>weights</parameter> <type>real[]</type>, </optional>
-        <parameter>vector</parameter> <type>tsvector</type>,
-        <parameter>query</parameter> <type>tsquery</type>
-        <optional>, <parameter>normalization</parameter> <type>integer</type> </optional> )
-        <returnvalue>real</returnvalue>
-       </para>
-       <para>
-        Computes a score showing how well
-        the <parameter>vector</parameter> matches
-        the <parameter>query</parameter>, using a cover density
-        algorithm.  See <xref linkend="textsearch-ranking"/> for details.
-       </para>
-       <para>
-        <literal>ts_rank_cd(to_tsvector('raining cats and dogs'), 'cat')</literal>
-        <returnvalue>0.1</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>ts_rewrite</primary>
-        </indexterm>
-        <function>ts_rewrite</function> ( <parameter>query</parameter> <type>tsquery</type>,
-        <parameter>target</parameter> <type>tsquery</type>,
-        <parameter>substitute</parameter> <type>tsquery</type> )
-        <returnvalue>tsquery</returnvalue>
-       </para>
-       <para>
-        Replaces occurrences of <parameter>target</parameter>
-        with <parameter>substitute</parameter>
-        within the <parameter>query</parameter>.
-        See <xref linkend="textsearch-query-rewriting"/> for details.
-       </para>
-       <para>
-        <literal>ts_rewrite('a &amp; b'::tsquery, 'a'::tsquery, 'foo|bar'::tsquery)</literal>
-        <returnvalue>'b' &amp; ( 'foo' | 'bar' )</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>ts_rewrite</function> ( <parameter>query</parameter> <type>tsquery</type>,
-        <parameter>select</parameter> <type>text</type> )
-        <returnvalue>tsquery</returnvalue>
-       </para>
-       <para>
-        Replaces portions of the <parameter>query</parameter> according to
-        target(s) and substitute(s) obtained by executing
-        a <command>SELECT</command> command.
-        See <xref linkend="textsearch-query-rewriting"/> for details.
-       </para>
-       <para>
-        <literal>SELECT ts_rewrite('a &amp; b'::tsquery, 'SELECT t,s FROM aliases')</literal>
-        <returnvalue>'b' &amp; ( 'foo' | 'bar' )</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>tsquery_phrase</primary>
-        </indexterm>
-        <function>tsquery_phrase</function> ( <parameter>query1</parameter> <type>tsquery</type>, <parameter>query2</parameter> <type>tsquery</type> )
-        <returnvalue>tsquery</returnvalue>
-       </para>
-       <para>
-        Constructs a phrase query that searches
-        for matches of <parameter>query1</parameter>
-        and <parameter>query2</parameter> at successive lexemes (same
-        as <literal>&lt;-&gt;</literal> operator).
-       </para>
-       <para>
-        <literal>tsquery_phrase(to_tsquery('fat'), to_tsquery('cat'))</literal>
-        <returnvalue>'fat' &lt;-&gt; 'cat'</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>tsquery_phrase</function> ( <parameter>query1</parameter> <type>tsquery</type>, <parameter>query2</parameter> <type>tsquery</type>, <parameter>distance</parameter> <type>integer</type> )
-        <returnvalue>tsquery</returnvalue>
-       </para>
-       <para>
-        Constructs a phrase query that searches
-        for matches of <parameter>query1</parameter> and
-        <parameter>query2</parameter> that occur exactly
-        <parameter>distance</parameter> lexemes apart.
-       </para>
-       <para>
-        <literal>tsquery_phrase(to_tsquery('fat'), to_tsquery('cat'), 10)</literal>
-        <returnvalue>'fat' &lt;10&gt; 'cat'</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>tsvector_to_array</primary>
-        </indexterm>
-        <function>tsvector_to_array</function> ( <type>tsvector</type> )
-        <returnvalue>text[]</returnvalue>
-       </para>
-       <para>
-        Converts a <type>tsvector</type> to an array of lexemes.
-       </para>
-       <para>
-        <literal>tsvector_to_array('fat:2,4 cat:3 rat:5A'::tsvector)</literal>
-        <returnvalue>{cat,fat,rat}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>unnest</primary>
-         <secondary>for tsvector</secondary>
-        </indexterm>
-        <function>unnest</function> ( <type>tsvector</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>lexeme</parameter> <type>text</type>,
-        <parameter>positions</parameter> <type>smallint[]</type>,
-        <parameter>weights</parameter> <type>text</type> )
-       </para>
-       <para>
-        Expands a <type>tsvector</type> into a set of rows, one per lexeme.
-       </para>
-       <para>
-        <literal>select * from unnest('cat:3 fat:2,4 rat:5A'::tsvector)</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- lexeme | positions | weights
---------+-----------+---------
- cat    | {3}       | {D}
- fat    | {2,4}     | {D,D}
- rat    | {5}       | {A}
-</programlisting>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <note>
-   <para>
-    All the text search functions that accept an optional <type>regconfig</type>
-    argument will use the configuration specified by
-    <xref linkend="guc-default-text-search-config"/>
-    when that argument is omitted.
-   </para>
-  </note>
-
-  <para>
-   The functions in
-   <xref linkend="textsearch-functions-debug-table"/>
-   are listed separately because they are not usually used in everyday text
-   searching operations.  They are primarily helpful for development and
-   debugging of new text search configurations.
-  </para>
-
-   <table id="textsearch-functions-debug-table">
-    <title>Text Search Debugging Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>ts_debug</primary>
-        </indexterm>
-        <function>ts_debug</function> (
-        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
-        <parameter>document</parameter> <type>text</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>alias</parameter> <type>text</type>,
-        <parameter>description</parameter> <type>text</type>,
-        <parameter>token</parameter> <type>text</type>,
-        <parameter>dictionaries</parameter> <type>regdictionary[]</type>,
-        <parameter>dictionary</parameter> <type>regdictionary</type>,
-        <parameter>lexemes</parameter> <type>text[]</type> )
-       </para>
-       <para>
-        Extracts and normalizes tokens from
-        the <parameter>document</parameter> according to the specified or
-        default text search configuration, and returns information about how
-        each token was processed.
-        See <xref linkend="textsearch-configuration-testing"/> for details.
-       </para>
-       <para>
-        <literal>ts_debug('english', 'The Brightest supernovaes')</literal>
-        <returnvalue>(asciiword,"Word, all ASCII",The,{english_stem},english_stem,{}) ...</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>ts_lexize</primary>
-        </indexterm>
-        <function>ts_lexize</function> ( <parameter>dict</parameter> <type>regdictionary</type>, <parameter>token</parameter> <type>text</type> )
-        <returnvalue>text[]</returnvalue>
-       </para>
-       <para>
-        Returns an array of replacement lexemes if the input token is known to
-        the dictionary, or an empty array if the token is known to the
-        dictionary but it is a stop word, or NULL if it is not a known word.
-        See <xref linkend="textsearch-dictionary-testing"/> for details.
-       </para>
-       <para>
-        <literal>ts_lexize('english_stem', 'stars')</literal>
-        <returnvalue>{star}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>ts_parse</primary>
-        </indexterm>
-        <function>ts_parse</function> ( <parameter>parser_name</parameter> <type>text</type>,
-        <parameter>document</parameter> <type>text</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>tokid</parameter> <type>integer</type>,
-        <parameter>token</parameter> <type>text</type> )
-       </para>
-       <para>
-        Extracts tokens from the <parameter>document</parameter> using the
-        named parser.
-        See <xref linkend="textsearch-parser-testing"/> for details.
-       </para>
-       <para>
-        <literal>ts_parse('default', 'foo - bar')</literal>
-        <returnvalue>(1,foo) ...</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>ts_parse</function> ( <parameter>parser_oid</parameter> <type>oid</type>,
-        <parameter>document</parameter> <type>text</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>tokid</parameter> <type>integer</type>,
-        <parameter>token</parameter> <type>text</type> )
-       </para>
-       <para>
-        Extracts tokens from the <parameter>document</parameter> using a
-        parser specified by OID.
-        See <xref linkend="textsearch-parser-testing"/> for details.
-       </para>
-       <para>
-        <literal>ts_parse(3722, 'foo - bar')</literal>
-        <returnvalue>(1,foo) ...</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>ts_token_type</primary>
-        </indexterm>
-        <function>ts_token_type</function> ( <parameter>parser_name</parameter> <type>text</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>tokid</parameter> <type>integer</type>,
-        <parameter>alias</parameter> <type>text</type>,
-        <parameter>description</parameter> <type>text</type> )
-       </para>
-       <para>
-        Returns a table that describes each type of token the named parser can
-        recognize.
-        See <xref linkend="textsearch-parser-testing"/> for details.
-       </para>
-       <para>
-        <literal>ts_token_type('default')</literal>
-        <returnvalue>(1,asciiword,"Word, all ASCII") ...</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>ts_token_type</function> ( <parameter>parser_oid</parameter> <type>oid</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>tokid</parameter> <type>integer</type>,
-        <parameter>alias</parameter> <type>text</type>,
-        <parameter>description</parameter> <type>text</type> )
-       </para>
-       <para>
-        Returns a table that describes each type of token a parser specified
-        by OID can recognize.
-        See <xref linkend="textsearch-parser-testing"/> for details.
-       </para>
-       <para>
-        <literal>ts_token_type(3722)</literal>
-        <returnvalue>(1,asciiword,"Word, all ASCII") ...</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>ts_stat</primary>
-        </indexterm>
-        <function>ts_stat</function> ( <parameter>sqlquery</parameter> <type>text</type>
-        <optional>, <parameter>weights</parameter> <type>text</type> </optional> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>word</parameter> <type>text</type>,
-        <parameter>ndoc</parameter> <type>integer</type>,
-        <parameter>nentry</parameter> <type>integer</type> )
-       </para>
-       <para>
-        Executes the <parameter>sqlquery</parameter>, which must return a
-        single <type>tsvector</type> column, and returns statistics about each
-        distinct lexeme contained in the data.
-        See <xref linkend="textsearch-statistics"/> for details.
-       </para>
-       <para>
-        <literal>ts_stat('SELECT vector FROM apod')</literal>
-        <returnvalue>(foo,10,15) ...</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
- </sect1>
-
- <sect1 id="functions-uuid">
-  <title>UUID Functions</title>
-
-  <indexterm zone="functions-uuid">
-   <primary>UUID</primary>
-   <secondary>generating</secondary>
-  </indexterm>
-
-  <indexterm>
-   <primary>gen_random_uuid</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>uuidv4</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>uuidv7</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>uuid_extract_timestamp</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>uuid_extract_version</primary>
-  </indexterm>
-
-  <para>
-   <xref linkend="func_uuid_gen_table"/> shows the <productname>PostgreSQL</productname>
-   functions that can be used to generate UUIDs.
-  </para>
-
-  <table id="func_uuid_gen_table">
-   <title><acronym>UUID</acronym> Generation Functions</title>
-   <tgroup cols="1">
-    <thead>
-     <row>
-      <entry role="func_table_entry">
-       <para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-        </para>
-       <para>
-        Example(s)
-       </para>
-       </entry>
-     </row>
-    </thead>
-
-    <tbody>
-     <row>
-      <entry role="func_table_entry">
-       <para role="func_signature">
-        <type>gen_random_uuid</type>
-        <returnvalue>uuid</returnvalue>
-       </para>
-       <para role="func_signature">
-        <type>uuidv4</type>
-        <returnvalue>uuid</returnvalue>
-       </para>
-       <para>
-         Generate a version 4 (random) UUID.
-       </para>
-       <para>
-        <literal>gen_random_uuid()</literal>
-        <returnvalue>5b30857f-0bfa-48b5-ac0b-5c64e28078d1</returnvalue>
-       </para>
-       <para>
-        <literal>uuidv4()</literal>
-        <returnvalue>b42410ee-132f-42ee-9e4f-09a6485c95b8</returnvalue>
-       </para>
-      </entry>
-     </row>
-     <row>
-      <entry role="func_table_entry">
-       <para role="func_signature">
-        <type>uuidv7</type>
-        ( <optional> <parameter>shift</parameter> <type>interval</type> </optional> )
-        <returnvalue>uuid</returnvalue>
-       </para>
-       <para>
-        Generate a version 7 (time-ordered) UUID. The timestamp is computed using UNIX timestamp
-        with millisecond precision + sub-millisecond timestamp + random. The optional parameter
-        <parameter>shift</parameter> will shift the computed timestamp by the given <type>interval</type>.
-       </para>
-       <para>
-        <literal>uuidv7()</literal>
-        <returnvalue>019535d9-3df7-79fb-b466-fa907fa17f9e</returnvalue>
-       </para>
-      </entry>
-     </row>
-    </tbody>
-   </tgroup>
-  </table>
-
-  <note>
-   <para>
-    The <xref linkend="uuid-ossp"/> module provides additional functions that
-    implement other standard algorithms for generating UUIDs.
-   </para>
-  </note>
-
-  <para>
-   <xref linkend="func_uuid_extract_table"/> shows the <productname>PostgreSQL</productname>
-   functions that can be used to extract information from UUIDs.
-  </para>
-
-  <table id="func_uuid_extract_table">
-   <title><acronym>UUID</acronym> Extraction Functions</title>
-   <tgroup cols="1">
-    <thead>
-     <row>
-      <entry role="func_table_entry">
-       <para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para>
-      </entry>
-     </row>
-    </thead>
-
-    <tbody>
-     <row>
-      <entry role="func_table_entry">
-       <para role="func_signature">
-        <type>uuid_extract_timestamp</type>
-        ( <type>uuid</type> )
-        <returnvalue>timestamp with time zone</returnvalue>
-       </para>
-       <para>
-        Extracts a <type>timestamp with time zone</type> from UUID
-        version 1 and 7.  For other versions, this function returns null.  Note that
-        the extracted timestamp is not necessarily exactly equal to the time the
-        UUID was generated; this depends on the implementation that generated the
-        UUID.
-       </para>
-       <para>
-        <literal>uuid_extract_timestamp('019535d9-3df7-79fb-b466-&zwsp;fa907fa17f9e'::uuid)</literal>
-         <returnvalue>2025-02-23 21:46:24.503-05</returnvalue>
-       </para>
-      </entry>
-     </row>
-     <row>
-      <entry role="func_table_entry">
-       <para role="func_signature">
-        <type>uuid_extract_version</type>
-        ( <type>uuid</type> )
-        <returnvalue>smallint</returnvalue>
-       </para>
-       <para>
-        Extracts the version from a UUID of the variant described by
-        <ulink url="https://datatracker.ietf.org/doc/html/rfc9562">RFC 9562</ulink>.  For
-        other variants, this function returns null.  For example, for a UUID
-        generated by <function>gen_random_uuid</function>, this function will
-        return 4.
-       </para>
-       <para>
-        <literal>uuid_extract_version('41db1265-8bc1-4ab3-992f-&zwsp;885799a4af1d'::uuid)</literal>
-        <returnvalue>4</returnvalue>
-       </para>
-       <para>
-        <literal>uuid_extract_version('019535d9-3df7-79fb-b466-&zwsp;fa907fa17f9e'::uuid)</literal>
-        <returnvalue>7</returnvalue>
-       </para>
-      </entry>
-     </row>
-    </tbody>
-   </tgroup>
-  </table>
-
-  <para>
-   <productname>PostgreSQL</productname> also provides the usual comparison
-   operators shown in <xref linkend="functions-comparison-op-table"/> for
-   UUIDs.
-  </para>
-  <para>
-   See <xref linkend="datatype-uuid"/> for details on the data type
-   <type>uuid</type> in <productname>PostgreSQL</productname>.
-  </para>
- </sect1>
-
- <sect1 id="functions-xml">
-
-  <title>XML Functions</title>
-
-  <indexterm>
-   <primary>XML Functions</primary>
-  </indexterm>
-
-  <para>
-   The functions and function-like expressions described in this
-   section operate on values of type <type>xml</type>.  See <xref
-   linkend="datatype-xml"/> for information about the <type>xml</type>
-   type.  The function-like expressions <function>xmlparse</function>
-   and <function>xmlserialize</function> for converting to and from
-   type <type>xml</type> are documented there, not in this section.
-  </para>
-
-  <para>
-   Use of most of these functions
-   requires <productname>PostgreSQL</productname> to have been built
-   with <command>configure --with-libxml</command>.
-  </para>
-
-  <sect2 id="functions-producing-xml">
-   <title>Producing XML Content</title>
-
-   <para>
-    A set of functions and function-like expressions is available for
-    producing XML content from SQL data.  As such, they are
-    particularly suitable for formatting query results into XML
-    documents for processing in client applications.
-   </para>
-
-  <sect3 id="functions-producing-xml-xmltext">
-    <title><literal>xmltext</literal></title>
-
-    <indexterm>
-     <primary>xmltext</primary>
-    </indexterm>
-
-<synopsis>
-<function>xmltext</function> ( <type>text</type> ) <returnvalue>xml</returnvalue>
-</synopsis>
-
-    <para>
-     The function <function>xmltext</function> returns an XML value with a single
-     text node containing the input argument as its content. Predefined entities
-     like ampersand (<literal><![CDATA[&]]></literal>), left and right angle brackets
-     (<literal><![CDATA[< >]]></literal>), and quotation marks (<literal><![CDATA[""]]></literal>)
-     are escaped.
-    </para>
-
-    <para>
-     Example:
-<screen><![CDATA[
-SELECT xmltext('< foo & bar >');
-         xmltext
--------------------------
- &lt; foo &amp; bar &gt;
-]]></screen>
-    </para>
-   </sect3>
-
-   <sect3 id="functions-producing-xml-xmlcomment">
-    <title><literal>xmlcomment</literal></title>
-
-    <indexterm>
-     <primary>xmlcomment</primary>
-    </indexterm>
-
-<synopsis>
-<function>xmlcomment</function> ( <type>text</type> ) <returnvalue>xml</returnvalue>
-</synopsis>
-
-    <para>
-     The function <function>xmlcomment</function> creates an XML value
-     containing an XML comment with the specified text as content.
-     The text cannot contain <quote><literal>--</literal></quote> or end with a
-     <quote><literal>-</literal></quote>, otherwise the resulting construct
-     would not be a valid XML comment.
-     If the argument is null, the result is null.
-    </para>
-
-    <para>
-     Example:
-<screen><![CDATA[
-SELECT xmlcomment('hello');
-
-  xmlcomment
---------------
- <!--hello-->
-]]></screen>
-    </para>
-   </sect3>
-
-   <sect3 id="functions-producing-xml-xmlconcat">
-    <title><literal>xmlconcat</literal></title>
-
-    <indexterm>
-     <primary>xmlconcat</primary>
-    </indexterm>
-
-<synopsis>
-<function>xmlconcat</function> ( <type>xml</type> <optional>, ...</optional> ) <returnvalue>xml</returnvalue>
-</synopsis>
-
-    <para>
-     The function <function>xmlconcat</function> concatenates a list
-     of individual XML values to create a single value containing an
-     XML content fragment.  Null values are omitted; the result is
-     only null if there are no nonnull arguments.
-    </para>
-
-    <para>
-     Example:
-<screen><![CDATA[
-SELECT xmlconcat('<abc/>', '<bar>foo</bar>');
-
-      xmlconcat
-----------------------
- <abc/><bar>foo</bar>
-]]></screen>
-    </para>
-
-    <para>
-     XML declarations, if present, are combined as follows.  If all
-     argument values have the same XML version declaration, that
-     version is used in the result, else no version is used.  If all
-     argument values have the standalone declaration value
-     <quote>yes</quote>, then that value is used in the result.  If
-     all argument values have a standalone declaration value and at
-     least one is <quote>no</quote>, then that is used in the result.
-     Else the result will have no standalone declaration.  If the
-     result is determined to require a standalone declaration but no
-     version declaration, a version declaration with version 1.0 will
-     be used because XML requires an XML declaration to contain a
-     version declaration.  Encoding declarations are ignored and
-     removed in all cases.
-    </para>
-
-    <para>
-     Example:
-<screen><![CDATA[
-SELECT xmlconcat('<?xml version="1.1"?><foo/>', '<?xml version="1.1" standalone="no"?><bar/>');
-
-             xmlconcat
------------------------------------
- <?xml version="1.1"?><foo/><bar/>
-]]></screen>
-    </para>
-   </sect3>
-
-   <sect3 id="functions-producing-xml-xmlelement">
-    <title><literal>xmlelement</literal></title>
-
-   <indexterm>
-    <primary>xmlelement</primary>
-   </indexterm>
-
-<synopsis>
-<function>xmlelement</function> ( <literal>NAME</literal> <replaceable>name</replaceable> <optional>, <literal>XMLATTRIBUTES</literal> ( <replaceable>attvalue</replaceable> <optional> <literal>AS</literal> <replaceable>attname</replaceable> </optional> <optional>, ...</optional> ) </optional> <optional>, <replaceable>content</replaceable> <optional>, ...</optional></optional> ) <returnvalue>xml</returnvalue>
-</synopsis>
-
-    <para>
-     The <function>xmlelement</function> expression produces an XML
-     element with the given name, attributes, and content.
-     The <replaceable>name</replaceable>
-     and <replaceable>attname</replaceable> items shown in the syntax are
-     simple identifiers, not values.  The <replaceable>attvalue</replaceable>
-     and <replaceable>content</replaceable> items are expressions, which can
-     yield any <productname>PostgreSQL</productname> data type.  The
-     argument(s) within <literal>XMLATTRIBUTES</literal> generate attributes
-     of the XML element; the <replaceable>content</replaceable> value(s) are
-     concatenated to form its content.
-    </para>
-
-    <para>
-     Examples:
-<screen><![CDATA[
-SELECT xmlelement(name foo);
-
- xmlelement
-------------
- <foo/>
-
-SELECT xmlelement(name foo, xmlattributes('xyz' as bar));
-
-    xmlelement
-------------------
- <foo bar="xyz"/>
-
-SELECT xmlelement(name foo, xmlattributes(current_date as bar), 'cont', 'ent');
-
-             xmlelement
--------------------------------------
- <foo bar="2007-01-26">content</foo>
-]]></screen>
-    </para>
-
-    <para>
-     Element and attribute names that are not valid XML names are
-     escaped by replacing the offending characters by the sequence
-     <literal>_x<replaceable>HHHH</replaceable>_</literal>, where
-     <replaceable>HHHH</replaceable> is the character's Unicode
-     codepoint in hexadecimal notation.  For example:
-<screen><![CDATA[
-SELECT xmlelement(name "foo$bar", xmlattributes('xyz' as "a&b"));
-
-            xmlelement
-----------------------------------
- <foo_x0024_bar a_x0026_b="xyz"/>
-]]></screen>
-    </para>
-
-    <para>
-     An explicit attribute name need not be specified if the attribute
-     value is a column reference, in which case the column's name will
-     be used as the attribute name by default.  In other cases, the
-     attribute must be given an explicit name.  So this example is
-     valid:
-<screen>
-CREATE TABLE test (a xml, b xml);
-SELECT xmlelement(name test, xmlattributes(a, b)) FROM test;
-</screen>
-     But these are not:
-<screen>
-SELECT xmlelement(name test, xmlattributes('constant'), a, b) FROM test;
-SELECT xmlelement(name test, xmlattributes(func(a, b))) FROM test;
-</screen>
-    </para>
-
-    <para>
-     Element content, if specified, will be formatted according to
-     its data type.  If the content is itself of type <type>xml</type>,
-     complex XML documents can be constructed.  For example:
-<screen><![CDATA[
-SELECT xmlelement(name foo, xmlattributes('xyz' as bar),
-                            xmlelement(name abc),
-                            xmlcomment('test'),
-                            xmlelement(name xyz));
-
-                  xmlelement
-----------------------------------------------
- <foo bar="xyz"><abc/><!--test--><xyz/></foo>
-]]></screen>
-
-     Content of other types will be formatted into valid XML character
-     data.  This means in particular that the characters &lt;, &gt;,
-     and &amp; will be converted to entities.  Binary data (data type
-     <type>bytea</type>) will be represented in base64 or hex
-     encoding, depending on the setting of the configuration parameter
-     <xref linkend="guc-xmlbinary"/>.  The particular behavior for
-     individual data types is expected to evolve in order to align the
-     PostgreSQL mappings with those specified in SQL:2006 and later,
-     as discussed in <xref linkend="functions-xml-limits-casts"/>.
-    </para>
-   </sect3>
-
-   <sect3 id="functions-producing-xml-xmlforest">
-    <title><literal>xmlforest</literal></title>
-
-   <indexterm>
-    <primary>xmlforest</primary>
-   </indexterm>
-
-<synopsis>
-<function>xmlforest</function> ( <replaceable>content</replaceable> <optional> <literal>AS</literal> <replaceable>name</replaceable> </optional> <optional>, ...</optional> ) <returnvalue>xml</returnvalue>
-</synopsis>
-
-    <para>
-     The <function>xmlforest</function> expression produces an XML
-     forest (sequence) of elements using the given names and content.
-     As for <function>xmlelement</function>,
-     each <replaceable>name</replaceable> must be a simple identifier, while
-     the <replaceable>content</replaceable> expressions can have any data
-     type.
-    </para>
-
-    <para>
-     Examples:
-<screen>
-SELECT xmlforest('abc' AS foo, 123 AS bar);
-
-          xmlforest
-------------------------------
- &lt;foo&gt;abc&lt;/foo&gt;&lt;bar&gt;123&lt;/bar&gt;
-
-
-SELECT xmlforest(table_name, column_name)
-FROM information_schema.columns
-WHERE table_schema = 'pg_catalog';
-
-                                xmlforest
-------------------------------------&zwsp;-----------------------------------
- &lt;table_name&gt;pg_authid&lt;/table_name&gt;&zwsp;&lt;column_name&gt;rolname&lt;/column_name&gt;
- &lt;table_name&gt;pg_authid&lt;/table_name&gt;&zwsp;&lt;column_name&gt;rolsuper&lt;/column_name&gt;
- ...
-</screen>
-
-     As seen in the second example, the element name can be omitted if
-     the content value is a column reference, in which case the column
-     name is used by default.  Otherwise, a name must be specified.
-    </para>
-
-    <para>
-     Element names that are not valid XML names are escaped as shown
-     for <function>xmlelement</function> above.  Similarly, content
-     data is escaped to make valid XML content, unless it is already
-     of type <type>xml</type>.
-    </para>
-
-    <para>
-     Note that XML forests are not valid XML documents if they consist
-     of more than one element, so it might be useful to wrap
-     <function>xmlforest</function> expressions in
-     <function>xmlelement</function>.
-    </para>
-   </sect3>
-
-   <sect3 id="functions-producing-xml-xmlpi">
-    <title><literal>xmlpi</literal></title>
-
-   <indexterm>
-    <primary>xmlpi</primary>
-   </indexterm>
-
-<synopsis>
-<function>xmlpi</function> ( <literal>NAME</literal> <replaceable>name</replaceable> <optional>, <replaceable>content</replaceable> </optional> ) <returnvalue>xml</returnvalue>
-</synopsis>
-
-    <para>
-     The <function>xmlpi</function> expression creates an XML
-     processing instruction.
-     As for <function>xmlelement</function>,
-     the <replaceable>name</replaceable> must be a simple identifier, while
-     the <replaceable>content</replaceable> expression can have any data type.
-     The <replaceable>content</replaceable>, if present, must not contain the
-     character sequence <literal>?&gt;</literal>.
-    </para>
-
-    <para>
-     Example:
-<screen><![CDATA[
-SELECT xmlpi(name php, 'echo "hello world";');
-
-            xmlpi
------------------------------
- <?php echo "hello world";?>
-]]></screen>
-    </para>
-   </sect3>
-
-   <sect3 id="functions-producing-xml-xmlroot">
-    <title><literal>xmlroot</literal></title>
-
-   <indexterm>
-    <primary>xmlroot</primary>
-   </indexterm>
-
-<synopsis>
-<function>xmlroot</function> ( <type>xml</type>, <literal>VERSION</literal> {<type>text</type>|<literal>NO VALUE</literal>} <optional>, <literal>STANDALONE</literal> {<literal>YES</literal>|<literal>NO</literal>|<literal>NO VALUE</literal>} </optional> ) <returnvalue>xml</returnvalue>
-</synopsis>
-
-    <para>
-     The <function>xmlroot</function> expression alters the properties
-     of the root node of an XML value.  If a version is specified,
-     it replaces the value in the root node's version declaration; if a
-     standalone setting is specified, it replaces the value in the
-     root node's standalone declaration.
-    </para>
-
-    <para>
-<screen><![CDATA[
-SELECT xmlroot(xmlparse(document '<?xml version="1.1"?><content>abc</content>'),
-               version '1.0', standalone yes);
-
-                xmlroot
-----------------------------------------
- <?xml version="1.0" standalone="yes"?>
- <content>abc</content>
-]]></screen>
-    </para>
-   </sect3>
-
-   <sect3 id="functions-xml-xmlagg">
-    <title><literal>xmlagg</literal></title>
-
-    <indexterm>
-     <primary>xmlagg</primary>
-    </indexterm>
-
-<synopsis>
-<function>xmlagg</function> ( <type>xml</type> ) <returnvalue>xml</returnvalue>
-</synopsis>
-
-    <para>
-     The function <function>xmlagg</function> is, unlike the other
-     functions described here, an aggregate function.  It concatenates the
-     input values to the aggregate function call,
-     much like <function>xmlconcat</function> does, except that concatenation
-     occurs across rows rather than across expressions in a single row.
-     See <xref linkend="functions-aggregate"/> for additional information
-     about aggregate functions.
-    </para>
-
-    <para>
-     Example:
-<screen><![CDATA[
-CREATE TABLE test (y int, x xml);
-INSERT INTO test VALUES (1, '<foo>abc</foo>');
-INSERT INTO test VALUES (2, '<bar/>');
-SELECT xmlagg(x) FROM test;
-        xmlagg
-----------------------
- <foo>abc</foo><bar/>
-]]></screen>
-    </para>
-
-    <para>
-     To determine the order of the concatenation, an <literal>ORDER BY</literal>
-     clause may be added to the aggregate call as described in
-     <xref linkend="syntax-aggregates"/>. For example:
-
-<screen><![CDATA[
-SELECT xmlagg(x ORDER BY y DESC) FROM test;
-        xmlagg
-----------------------
- <bar/><foo>abc</foo>
-]]></screen>
-    </para>
-
-    <para>
-     The following non-standard approach used to be recommended
-     in previous versions, and may still be useful in specific
-     cases:
-
-<screen><![CDATA[
-SELECT xmlagg(x) FROM (SELECT * FROM test ORDER BY y DESC) AS tab;
-        xmlagg
-----------------------
- <bar/><foo>abc</foo>
-]]></screen>
-    </para>
-   </sect3>
-   </sect2>
-
-   <sect2 id="functions-xml-predicates">
-    <title>XML Predicates</title>
-
-    <para>
-     The expressions described in this section check properties
-     of <type>xml</type> values.
-    </para>
-
-   <sect3 id="functions-producing-xml-is-document">
-    <title><literal>IS DOCUMENT</literal></title>
-
-    <indexterm>
-     <primary>IS DOCUMENT</primary>
-    </indexterm>
-
-<synopsis>
-<type>xml</type> <literal>IS DOCUMENT</literal> <returnvalue>boolean</returnvalue>
-</synopsis>
-
-    <para>
-     The expression <literal>IS DOCUMENT</literal> returns true if the
-     argument XML value is a proper XML document, false if it is not
-     (that is, it is a content fragment), or null if the argument is
-     null.  See <xref linkend="datatype-xml"/> about the difference
-     between documents and content fragments.
-    </para>
-   </sect3>
-
-   <sect3 id="functions-producing-xml-is-not-document">
-    <title><literal>IS NOT DOCUMENT</literal></title>
-
-    <indexterm>
-     <primary>IS NOT DOCUMENT</primary>
-    </indexterm>
-
-<synopsis>
-<type>xml</type> <literal>IS NOT DOCUMENT</literal> <returnvalue>boolean</returnvalue>
-</synopsis>
-
-    <para>
-     The expression <literal>IS NOT DOCUMENT</literal> returns false if the
-     argument XML value is a proper XML document, true if it is not (that is,
-     it is a content fragment), or null if the argument is null.
-    </para>
-   </sect3>
-
-   <sect3 id="xml-exists">
-    <title><literal>XMLEXISTS</literal></title>
-
-    <indexterm>
-     <primary>XMLEXISTS</primary>
-    </indexterm>
-
-<synopsis>
-<function>XMLEXISTS</function> ( <type>text</type> <literal>PASSING</literal> <optional><literal>BY</literal> {<literal>REF</literal>|<literal>VALUE</literal>}</optional> <type>xml</type> <optional><literal>BY</literal> {<literal>REF</literal>|<literal>VALUE</literal>}</optional> ) <returnvalue>boolean</returnvalue>
-</synopsis>
-
-    <para>
-     The function <function>xmlexists</function> evaluates an XPath 1.0
-     expression (the first argument), with the passed XML value as its context
-     item.  The function returns false if the result of that evaluation
-     yields an empty node-set, true if it yields any other value.  The
-     function returns null if any argument is null.  A nonnull value
-     passed as the context item must be an XML document, not a content
-     fragment or any non-XML value.
-    </para>
-
-    <para>
-     Example:
-     <screen><![CDATA[
-SELECT xmlexists('//town[text() = ''Toronto'']' PASSING BY VALUE '<towns><town>Toronto</town><town>Ottawa</town></towns>');
-
- xmlexists
-------------
- t
-(1 row)
-]]></screen>
-    </para>
-
-    <para>
-     The <literal>BY REF</literal> and <literal>BY VALUE</literal> clauses
-     are accepted in <productname>PostgreSQL</productname>, but are ignored,
-     as discussed in <xref linkend="functions-xml-limits-postgresql"/>.
-    </para>
-
-    <para>
-     In the SQL standard, the <function>xmlexists</function> function
-     evaluates an expression in the XML Query language,
-     but <productname>PostgreSQL</productname> allows only an XPath 1.0
-     expression, as discussed in
-     <xref linkend="functions-xml-limits-xpath1"/>.
-    </para>
-   </sect3>
-
-   <sect3 id="xml-is-well-formed">
-    <title><literal>xml_is_well_formed</literal></title>
-
-    <indexterm>
-     <primary>xml_is_well_formed</primary>
-    </indexterm>
-
-    <indexterm>
-     <primary>xml_is_well_formed_document</primary>
-    </indexterm>
-
-    <indexterm>
-     <primary>xml_is_well_formed_content</primary>
-    </indexterm>
-
-<synopsis>
-<function>xml_is_well_formed</function> ( <type>text</type> ) <returnvalue>boolean</returnvalue>
-<function>xml_is_well_formed_document</function> ( <type>text</type> ) <returnvalue>boolean</returnvalue>
-<function>xml_is_well_formed_content</function> ( <type>text</type> ) <returnvalue>boolean</returnvalue>
-</synopsis>
-
-    <para>
-     These functions check whether a <type>text</type> string represents
-     well-formed XML, returning a Boolean result.
-     <function>xml_is_well_formed_document</function> checks for a well-formed
-     document, while <function>xml_is_well_formed_content</function> checks
-     for well-formed content.  <function>xml_is_well_formed</function> does
-     the former if the <xref linkend="guc-xmloption"/> configuration
-     parameter is set to <literal>DOCUMENT</literal>, or the latter if it is set to
-     <literal>CONTENT</literal>.  This means that
-     <function>xml_is_well_formed</function> is useful for seeing whether
-     a simple cast to type <type>xml</type> will succeed, whereas the other two
-     functions are useful for seeing whether the corresponding variants of
-     <function>XMLPARSE</function> will succeed.
-    </para>
-
-    <para>
-     Examples:
-
-<screen><![CDATA[
-SET xmloption TO DOCUMENT;
-SELECT xml_is_well_formed('<>');
- xml_is_well_formed
---------------------
- f
-(1 row)
-
-SELECT xml_is_well_formed('<abc/>');
- xml_is_well_formed
---------------------
- t
-(1 row)
-
-SET xmloption TO CONTENT;
-SELECT xml_is_well_formed('abc');
- xml_is_well_formed
---------------------
- t
-(1 row)
-
-SELECT xml_is_well_formed_document('<pg:foo xmlns:pg="http://postgresql.org/stuff">bar</pg:foo>');
- xml_is_well_formed_document
------------------------------
- t
-(1 row)
-
-SELECT xml_is_well_formed_document('<pg:foo xmlns:pg="http://postgresql.org/stuff">bar</my:foo>');
- xml_is_well_formed_document
------------------------------
- f
-(1 row)
-]]></screen>
-
-     The last example shows that the checks include whether
-     namespaces are correctly matched.
-    </para>
-   </sect3>
-  </sect2>
-
-  <sect2 id="functions-xml-processing">
-   <title>Processing XML</title>
-
-   <para>
-    To process values of data type <type>xml</type>, PostgreSQL offers
-    the functions <function>xpath</function> and
-    <function>xpath_exists</function>, which evaluate XPath 1.0
-    expressions, and the <function>XMLTABLE</function>
-    table function.
-   </para>
-
-   <sect3 id="functions-xml-processing-xpath">
-    <title><literal>xpath</literal></title>
-
-    <indexterm>
-     <primary>XPath</primary>
-    </indexterm>
-
-<synopsis>
-<function>xpath</function> ( <parameter>xpath</parameter> <type>text</type>, <parameter>xml</parameter> <type>xml</type> <optional>, <parameter>nsarray</parameter> <type>text[]</type> </optional> ) <returnvalue>xml[]</returnvalue>
-</synopsis>
-
-    <para>
-     The function <function>xpath</function> evaluates the XPath 1.0
-     expression <parameter>xpath</parameter> (given as text)
-     against the XML value
-     <parameter>xml</parameter>.  It returns an array of XML values
-     corresponding to the node-set produced by the XPath expression.
-     If the XPath expression returns a scalar value rather than a node-set,
-     a single-element array is returned.
-    </para>
-
-    <para>
-     The second argument must be a well formed XML document. In particular,
-     it must have a single root node element.
-    </para>
-
-    <para>
-     The optional third argument of the function is an array of namespace
-     mappings.  This array should be a two-dimensional <type>text</type> array with
-     the length of the second axis being equal to 2 (i.e., it should be an
-     array of arrays, each of which consists of exactly 2 elements).
-     The first element of each array entry is the namespace name (alias), the
-     second the namespace URI. It is not required that aliases provided in
-     this array be the same as those being used in the XML document itself (in
-     other words, both in the XML document and in the <function>xpath</function>
-     function context, aliases are <emphasis>local</emphasis>).
-    </para>
-
-    <para>
-     Example:
-<screen><![CDATA[
-SELECT xpath('/my:a/text()', '<my:a xmlns:my="http://example.com">test</my:a>',
-             ARRAY[ARRAY['my', 'http://example.com']]);
-
- xpath
---------
- {test}
-(1 row)
-]]></screen>
-    </para>
-
-    <para>
-     To deal with default (anonymous) namespaces, do something like this:
-<screen><![CDATA[
-SELECT xpath('//mydefns:b/text()', '<a xmlns="http://example.com"><b>test</b></a>',
-             ARRAY[ARRAY['mydefns', 'http://example.com']]);
-
- xpath
---------
- {test}
-(1 row)
-]]></screen>
-    </para>
-   </sect3>
-
-   <sect3 id="functions-xml-processing-xpath-exists">
-    <title><literal>xpath_exists</literal></title>
-
-    <indexterm>
-     <primary>xpath_exists</primary>
-    </indexterm>
-
-<synopsis>
-<function>xpath_exists</function> ( <parameter>xpath</parameter> <type>text</type>, <parameter>xml</parameter> <type>xml</type> <optional>, <parameter>nsarray</parameter> <type>text[]</type> </optional> ) <returnvalue>boolean</returnvalue>
-</synopsis>
-
-    <para>
-     The function <function>xpath_exists</function> is a specialized form
-     of the <function>xpath</function> function.  Instead of returning the
-     individual XML values that satisfy the XPath 1.0 expression, this function
-     returns a Boolean indicating whether the query was satisfied or not
-     (specifically, whether it produced any value other than an empty node-set).
-     This function is equivalent to the <literal>XMLEXISTS</literal> predicate,
-     except that it also offers support for a namespace mapping argument.
-    </para>
-
-    <para>
-     Example:
-<screen><![CDATA[
-SELECT xpath_exists('/my:a/text()', '<my:a xmlns:my="http://example.com">test</my:a>',
-                     ARRAY[ARRAY['my', 'http://example.com']]);
-
- xpath_exists
---------------
- t
-(1 row)
-]]></screen>
-    </para>
-   </sect3>
-
-   <sect3 id="functions-xml-processing-xmltable">
-    <title><literal>xmltable</literal></title>
-
-    <indexterm>
-     <primary>xmltable</primary>
-    </indexterm>
-
-    <indexterm zone="functions-xml-processing-xmltable">
-     <primary>table function</primary>
-     <secondary>XMLTABLE</secondary>
-    </indexterm>
-
-<synopsis>
-<function>XMLTABLE</function> (
-    <optional> <literal>XMLNAMESPACES</literal> ( <replaceable>namespace_uri</replaceable> <literal>AS</literal> <replaceable>namespace_name</replaceable> <optional>, ...</optional> ), </optional>
-    <replaceable>row_expression</replaceable> <literal>PASSING</literal> <optional><literal>BY</literal> {<literal>REF</literal>|<literal>VALUE</literal>}</optional> <replaceable>document_expression</replaceable> <optional><literal>BY</literal> {<literal>REF</literal>|<literal>VALUE</literal>}</optional>
-    <literal>COLUMNS</literal> <replaceable>name</replaceable> { <replaceable>type</replaceable> <optional><literal>PATH</literal> <replaceable>column_expression</replaceable></optional> <optional><literal>DEFAULT</literal> <replaceable>default_expression</replaceable></optional> <optional><literal>NOT NULL</literal> | <literal>NULL</literal></optional>
-                  | <literal>FOR ORDINALITY</literal> }
-            <optional>, ...</optional>
-) <returnvalue>setof record</returnvalue>
-</synopsis>
-
-    <para>
-     The <function>xmltable</function> expression produces a table based
-     on an XML value, an XPath filter to extract rows, and a
-     set of column definitions.
-     Although it syntactically resembles a function, it can only appear
-     as a table in a query's <literal>FROM</literal> clause.
-    </para>
-
-    <para>
-     The optional <literal>XMLNAMESPACES</literal> clause gives a
-     comma-separated list of namespace definitions, where
-     each <replaceable>namespace_uri</replaceable> is a <type>text</type>
-     expression and each <replaceable>namespace_name</replaceable> is a simple
-     identifier.  It specifies the XML namespaces used in the document and
-     their aliases. A default namespace specification is not currently
-     supported.
-    </para>
-
-    <para>
-     The required <replaceable>row_expression</replaceable> argument is an
-     XPath 1.0 expression (given as <type>text</type>) that is evaluated,
-     passing the XML value <replaceable>document_expression</replaceable> as
-     its context item, to obtain a set of XML nodes. These nodes are what
-     <function>xmltable</function> transforms into output rows. No rows
-     will be produced if the <replaceable>document_expression</replaceable>
-     is null, nor if the <replaceable>row_expression</replaceable> produces
-     an empty node-set or any value other than a node-set.
-    </para>
-
-    <para>
-     <replaceable>document_expression</replaceable> provides the context
-     item for the <replaceable>row_expression</replaceable>. It must be a
-     well-formed XML document; fragments/forests are not accepted.
-     The <literal>BY REF</literal> and <literal>BY VALUE</literal> clauses
-     are accepted but ignored, as discussed in
-     <xref linkend="functions-xml-limits-postgresql"/>.
-    </para>
-
-    <para>
-     In the SQL standard, the <function>xmltable</function> function
-     evaluates expressions in the XML Query language,
-     but <productname>PostgreSQL</productname> allows only XPath 1.0
-     expressions, as discussed in
-     <xref linkend="functions-xml-limits-xpath1"/>.
-    </para>
-
-    <para>
-     The required <literal>COLUMNS</literal> clause specifies the
-     column(s) that will be produced in the output table.
-     See the syntax summary above for the format.
-     A name is required for each column, as is a data type
-     (unless <literal>FOR ORDINALITY</literal> is specified, in which case
-     type <type>integer</type> is implicit).  The path, default and
-     nullability clauses are optional.
-    </para>
-
-    <para>
-     A column marked <literal>FOR ORDINALITY</literal> will be populated
-     with row numbers, starting with 1, in the order of nodes retrieved from
-     the <replaceable>row_expression</replaceable>'s result node-set.
-     At most one column may be marked <literal>FOR ORDINALITY</literal>.
-    </para>
-
-    <note>
-     <para>
-      XPath 1.0 does not specify an order for nodes in a node-set, so code
-      that relies on a particular order of the results will be
-      implementation-dependent.  Details can be found in
-      <xref linkend="xml-xpath-1-specifics"/>.
-     </para>
-    </note>
-
-    <para>
-     The <replaceable>column_expression</replaceable> for a column is an
-     XPath 1.0 expression that is evaluated for each row, with the current
-     node from the <replaceable>row_expression</replaceable> result as its
-     context item, to find the value of the column.  If
-     no <replaceable>column_expression</replaceable> is given, then the
-     column name is used as an implicit path.
-    </para>
-
-    <para>
-     If a column's XPath expression returns a non-XML value (which is limited
-     to string, boolean, or double in XPath 1.0) and the column has a
-     PostgreSQL type other than <type>xml</type>, the column will be set
-     as if by assigning the value's string representation to the PostgreSQL
-     type.  (If the value is a boolean, its string representation is taken
-     to be <literal>1</literal> or <literal>0</literal> if the output
-     column's type category is numeric, otherwise <literal>true</literal> or
-     <literal>false</literal>.)
-    </para>
-
-    <para>
-     If a column's XPath expression returns a non-empty set of XML nodes
-     and the column's PostgreSQL type is <type>xml</type>, the column will
-     be assigned the expression result exactly, if it is of document or
-     content form.
-     <footnote>
-      <para>
-       A result containing more than one element node at the top level, or
-       non-whitespace text outside of an element, is an example of content form.
-       An XPath result can be of neither form, for example if it returns an
-       attribute node selected from the element that contains it. Such a result
-       will be put into content form with each such disallowed node replaced by
-       its string value, as defined for the XPath 1.0
-       <function>string</function> function.
-      </para>
-     </footnote>
-    </para>
-
-    <para>
-     A non-XML result assigned to an <type>xml</type> output column produces
-     content, a single text node with the string value of the result.
-     An XML result assigned to a column of any other type may not have more than
-     one node, or an error is raised. If there is exactly one node, the column
-     will be set as if by assigning the node's string
-     value (as defined for the XPath 1.0 <function>string</function> function)
-     to the PostgreSQL type.
-    </para>
-
-    <para>
-     The string value of an XML element is the concatenation, in document order,
-     of all text nodes contained in that element and its descendants. The string
-     value of an element with no descendant text nodes is an
-     empty string (not <literal>NULL</literal>).
-     Any <literal>xsi:nil</literal> attributes are ignored.
-     Note that the whitespace-only <literal>text()</literal> node between two non-text
-     elements is preserved, and that leading whitespace on a <literal>text()</literal>
-     node is not flattened.
-     The XPath 1.0 <function>string</function> function may be consulted for the
-     rules defining the string value of other XML node types and non-XML values.
-    </para>
-
-    <para>
-     The conversion rules presented here are not exactly those of the SQL
-     standard, as discussed in <xref linkend="functions-xml-limits-casts"/>.
-    </para>
-
-    <para>
-     If the path expression returns an empty node-set
-     (typically, when it does not match)
-     for a given row, the column will be set to <literal>NULL</literal>, unless
-     a <replaceable>default_expression</replaceable> is specified; then the
-     value resulting from evaluating that expression is used.
-    </para>
-
-    <para>
-     A <replaceable>default_expression</replaceable>, rather than being
-     evaluated immediately when <function>xmltable</function> is called,
-     is evaluated each time a default is needed for the column.
-     If the expression qualifies as stable or immutable, the repeat
-     evaluation may be skipped.
-     This means that you can usefully use volatile functions like
-     <function>nextval</function> in
-     <replaceable>default_expression</replaceable>.
-    </para>
-
-    <para>
-     Columns may be marked <literal>NOT NULL</literal>. If the
-     <replaceable>column_expression</replaceable> for a <literal>NOT
-     NULL</literal> column does not match anything and there is
-     no <literal>DEFAULT</literal> or
-     the <replaceable>default_expression</replaceable> also evaluates to null,
-     an error is reported.
-    </para>
-
-    <para>
-     Examples:
-  <screen><![CDATA[
-CREATE TABLE xmldata AS SELECT
-xml $$
-<ROWS>
-  <ROW id="1">
-    <COUNTRY_ID>AU</COUNTRY_ID>
-    <COUNTRY_NAME>Australia</COUNTRY_NAME>
-  </ROW>
-  <ROW id="5">
-    <COUNTRY_ID>JP</COUNTRY_ID>
-    <COUNTRY_NAME>Japan</COUNTRY_NAME>
-    <PREMIER_NAME>Shinzo Abe</PREMIER_NAME>
-    <SIZE unit="sq_mi">145935</SIZE>
-  </ROW>
-  <ROW id="6">
-    <COUNTRY_ID>SG</COUNTRY_ID>
-    <COUNTRY_NAME>Singapore</COUNTRY_NAME>
-    <SIZE unit="sq_km">697</SIZE>
-  </ROW>
-</ROWS>
-$$ AS data;
-
-SELECT xmltable.*
-  FROM xmldata,
-       XMLTABLE('//ROWS/ROW'
-                PASSING data
-                COLUMNS id int PATH '@id',
-                        ordinality FOR ORDINALITY,
-                        "COUNTRY_NAME" text,
-                        country_id text PATH 'COUNTRY_ID',
-                        size_sq_km float PATH 'SIZE[@unit = "sq_km"]',
-                        size_other text PATH
-                             'concat(SIZE[@unit!="sq_km"], " ", SIZE[@unit!="sq_km"]/@unit)',
-                        premier_name text PATH 'PREMIER_NAME' DEFAULT 'not specified');
-
- id | ordinality | COUNTRY_NAME | country_id | size_sq_km |  size_other  | premier_name
-----+------------+--------------+------------+------------+--------------+---------------
-  1 |          1 | Australia    | AU         |            |              | not specified
-  5 |          2 | Japan        | JP         |            | 145935 sq_mi | Shinzo Abe
-  6 |          3 | Singapore    | SG         |        697 |              | not specified
-]]></screen>
-
-     The following example shows concatenation of multiple text() nodes,
-     usage of the column name as XPath filter, and the treatment of whitespace,
-     XML comments and processing instructions:
-
-  <screen><![CDATA[
-CREATE TABLE xmlelements AS SELECT
-xml $$
-  <root>
-   <element>  Hello<!-- xyxxz -->2a2<?aaaaa?> <!--x-->  bbb<x>xxx</x>CC  </element>
-  </root>
-$$ AS data;
-
-SELECT xmltable.*
-  FROM xmlelements, XMLTABLE('/root' PASSING data COLUMNS element text);
-         element
--------------------------
-   Hello2a2   bbbxxxCC
-]]></screen>
-    </para>
-
-    <para>
-     The following example illustrates how
-     the <literal>XMLNAMESPACES</literal> clause can be used to specify
-     a list of namespaces
-     used in the XML document as well as in the XPath expressions:
-
-  <screen><![CDATA[
-WITH xmldata(data) AS (VALUES ('
-<example xmlns="http://example.com/myns" xmlns:B="http://example.com/b">
- <item foo="1" B:bar="2"/>
- <item foo="3" B:bar="4"/>
- <item foo="4" B:bar="5"/>
-</example>'::xml)
-)
-SELECT xmltable.*
-  FROM XMLTABLE(XMLNAMESPACES('http://example.com/myns' AS x,
-                              'http://example.com/b' AS "B"),
-             '/x:example/x:item'
-                PASSING (SELECT data FROM xmldata)
-                COLUMNS foo int PATH '@foo',
-                  bar int PATH '@B:bar');
- foo | bar
------+-----
-   1 |   2
-   3 |   4
-   4 |   5
-(3 rows)
-]]></screen>
-    </para>
-   </sect3>
-  </sect2>
-
-  <sect2 id="functions-xml-mapping">
-   <title>Mapping Tables to XML</title>
-
-   <indexterm zone="functions-xml-mapping">
-    <primary>XML export</primary>
-   </indexterm>
-
-   <para>
-    The following functions map the contents of relational tables to
-    XML values.  They can be thought of as XML export functionality:
-<synopsis>
-<function>table_to_xml</function> ( <parameter>table</parameter> <type>regclass</type>, <parameter>nulls</parameter> <type>boolean</type>,
-               <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
-<function>query_to_xml</function> ( <parameter>query</parameter> <type>text</type>, <parameter>nulls</parameter> <type>boolean</type>,
-               <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
-<function>cursor_to_xml</function> ( <parameter>cursor</parameter> <type>refcursor</type>, <parameter>count</parameter> <type>integer</type>, <parameter>nulls</parameter> <type>boolean</type>,
-                <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
-</synopsis>
-   </para>
-
-   <para>
-    <function>table_to_xml</function> maps the content of the named
-    table, passed as parameter <parameter>table</parameter>.  The
-    <type>regclass</type> type accepts strings identifying tables using the
-    usual notation, including optional schema qualification and
-    double quotes (see <xref linkend="datatype-oid"/> for details).
-    <function>query_to_xml</function> executes the
-    query whose text is passed as parameter
-    <parameter>query</parameter> and maps the result set.
-    <function>cursor_to_xml</function> fetches the indicated number of
-    rows from the cursor specified by the parameter
-    <parameter>cursor</parameter>.  This variant is recommended if
-    large tables have to be mapped, because the result value is built
-    up in memory by each function.
-   </para>
-
-   <para>
-    If <parameter>tableforest</parameter> is false, then the resulting
-    XML document looks like this:
-<screen><![CDATA[
-<tablename>
-  <row>
-    <columnname1>data</columnname1>
-    <columnname2>data</columnname2>
-  </row>
-
-  <row>
-    ...
-  </row>
-
-  ...
-</tablename>
-]]></screen>
-
-    If <parameter>tableforest</parameter> is true, the result is an
-    XML content fragment that looks like this:
-<screen><![CDATA[
-<tablename>
-  <columnname1>data</columnname1>
-  <columnname2>data</columnname2>
-</tablename>
-
-<tablename>
-  ...
-</tablename>
-
-...
-]]></screen>
-
-    If no table name is available, that is, when mapping a query or a
-    cursor, the string <literal>table</literal> is used in the first
-    format, <literal>row</literal> in the second format.
-   </para>
-
-   <para>
-    The choice between these formats is up to the user.  The first
-    format is a proper XML document, which will be important in many
-    applications.  The second format tends to be more useful in the
-    <function>cursor_to_xml</function> function if the result values are to be
-    reassembled into one document later on.  The functions for
-    producing XML content discussed above, in particular
-    <function>xmlelement</function>, can be used to alter the results
-    to taste.
-   </para>
-
-   <para>
-    The data values are mapped in the same way as described for the
-    function <function>xmlelement</function> above.
-   </para>
-
-   <para>
-    The parameter <parameter>nulls</parameter> determines whether null
-    values should be included in the output.  If true, null values in
-    columns are represented as:
-<screen><![CDATA[
-<columnname xsi:nil="true"/>
-]]></screen>
-    where <literal>xsi</literal> is the XML namespace prefix for XML
-    Schema Instance.  An appropriate namespace declaration will be
-    added to the result value.  If false, columns containing null
-    values are simply omitted from the output.
-   </para>
-
-   <para>
-    The parameter <parameter>targetns</parameter> specifies the
-    desired XML namespace of the result.  If no particular namespace
-    is wanted, an empty string should be passed.
-   </para>
-
-   <para>
-    The following functions return XML Schema documents describing the
-    mappings performed by the corresponding functions above:
-<synopsis>
-<function>table_to_xmlschema</function> ( <parameter>table</parameter> <type>regclass</type>, <parameter>nulls</parameter> <type>boolean</type>,
-                     <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
-<function>query_to_xmlschema</function> ( <parameter>query</parameter> <type>text</type>, <parameter>nulls</parameter> <type>boolean</type>,
-                     <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
-<function>cursor_to_xmlschema</function> ( <parameter>cursor</parameter> <type>refcursor</type>, <parameter>nulls</parameter> <type>boolean</type>,
-                      <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
-</synopsis>
-    It is essential that the same parameters are passed in order to
-    obtain matching XML data mappings and XML Schema documents.
-   </para>
-
-   <para>
-    The following functions produce XML data mappings and the
-    corresponding XML Schema in one document (or forest), linked
-    together.  They can be useful where self-contained and
-    self-describing results are wanted:
-<synopsis>
-<function>table_to_xml_and_xmlschema</function> ( <parameter>table</parameter> <type>regclass</type>, <parameter>nulls</parameter> <type>boolean</type>,
-                             <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
-<function>query_to_xml_and_xmlschema</function> ( <parameter>query</parameter> <type>text</type>, <parameter>nulls</parameter> <type>boolean</type>,
-                             <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
-</synopsis>
-   </para>
-
-   <para>
-    In addition, the following functions are available to produce
-    analogous mappings of entire schemas or the entire current
-    database:
-<synopsis>
-<function>schema_to_xml</function> ( <parameter>schema</parameter> <type>name</type>, <parameter>nulls</parameter> <type>boolean</type>,
-                <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
-<function>schema_to_xmlschema</function> ( <parameter>schema</parameter> <type>name</type>, <parameter>nulls</parameter> <type>boolean</type>,
-                      <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
-<function>schema_to_xml_and_xmlschema</function> ( <parameter>schema</parameter> <type>name</type>, <parameter>nulls</parameter> <type>boolean</type>,
-                              <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
-
-<function>database_to_xml</function> ( <parameter>nulls</parameter> <type>boolean</type>,
-                  <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
-<function>database_to_xmlschema</function> ( <parameter>nulls</parameter> <type>boolean</type>,
-                        <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
-<function>database_to_xml_and_xmlschema</function> ( <parameter>nulls</parameter> <type>boolean</type>,
-                                <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
-</synopsis>
-
-    These functions ignore tables that are not readable by the current user.
-    The database-wide functions additionally ignore schemas that the current
-    user does not have <literal>USAGE</literal> (lookup) privilege for.
-   </para>
-
-   <para>
-    Note that these potentially produce a lot of data, which needs to
-    be built up in memory.  When requesting content mappings of large
-    schemas or databases, it might be worthwhile to consider mapping the
-    tables separately instead, possibly even through a cursor.
-   </para>
-
-   <para>
-    The result of a schema content mapping looks like this:
-
-<screen><![CDATA[
-<schemaname>
-
-table1-mapping
-
-table2-mapping
-
-...
-
-</schemaname>]]></screen>
-
-    where the format of a table mapping depends on the
-    <parameter>tableforest</parameter> parameter as explained above.
-   </para>
-
-   <para>
-    The result of a database content mapping looks like this:
-
-<screen><![CDATA[
-<dbname>
-
-<schema1name>
-  ...
-</schema1name>
-
-<schema2name>
-  ...
-</schema2name>
-
-...
-
-</dbname>]]></screen>
-
-    where the schema mapping is as above.
-   </para>
-
-   <para>
-    As an example of using the output produced by these functions,
-    <xref linkend="xslt-xml-html"/> shows an XSLT stylesheet that
-    converts the output of
-    <function>table_to_xml_and_xmlschema</function> to an HTML
-    document containing a tabular rendition of the table data.  In a
-    similar manner, the results from these functions can be
-    converted into other XML-based formats.
-   </para>
-
-   <example id="xslt-xml-html">
-    <title>XSLT Stylesheet for Converting SQL/XML Output to HTML</title>
-<programlisting><![CDATA[
-<?xml version="1.0"?>
-<xsl:stylesheet version="1.0"
-    xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
-    xmlns:xsd="http://www.w3.org/2001/XMLSchema"
-    xmlns="http://www.w3.org/1999/xhtml"
->
-
-  <xsl:output method="xml"
-      doctype-system="http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"
-      doctype-public="-//W3C/DTD XHTML 1.0 Strict//EN"
-      indent="yes"/>
-
-  <xsl:template match="/*">
-    <xsl:variable name="schema" select="//xsd:schema"/>
-    <xsl:variable name="tabletypename"
-                  select="$schema/xsd:element[@name=name(current())]/@type"/>
-    <xsl:variable name="rowtypename"
-                  select="$schema/xsd:complexType[@name=$tabletypename]/xsd:sequence/xsd:element[@name='row']/@type"/>
-
-    <html>
-      <head>
-        <title><xsl:value-of select="name(current())"/></title>
-      </head>
-      <body>
-        <table>
-          <tr>
-            <xsl:for-each select="$schema/xsd:complexType[@name=$rowtypename]/xsd:sequence/xsd:element/@name">
-              <th><xsl:value-of select="."/></th>
-            </xsl:for-each>
-          </tr>
-
-          <xsl:for-each select="row">
-            <tr>
-              <xsl:for-each select="*">
-                <td><xsl:value-of select="."/></td>
-              </xsl:for-each>
-            </tr>
-          </xsl:for-each>
-        </table>
-      </body>
-    </html>
-  </xsl:template>
-
-</xsl:stylesheet>
-]]></programlisting>
-   </example>
-  </sect2>
- </sect1>
-
- <sect1 id="functions-json">
-  <title>JSON Functions and Operators</title>
-
-  <indexterm zone="functions-json">
-   <primary>JSON</primary>
-   <secondary>functions and operators</secondary>
-  </indexterm>
-   <indexterm zone="functions-json">
-    <primary>SQL/JSON</primary>
-    <secondary>functions and expressions</secondary>
-   </indexterm>
-
-  <para>
-   This section describes:
-
-   <itemizedlist>
-    <listitem>
-     <para>
-      functions and operators for processing and creating JSON data
-     </para>
-    </listitem>
-    <listitem>
-     <para>
-      the SQL/JSON path language
-     </para>
-    </listitem>
-    <listitem>
-     <para>
-      the SQL/JSON query functions
-     </para>
-    </listitem>
-   </itemizedlist>
-  </para>
-
-  <para>
-   To provide native support for JSON data types within the SQL environment,
-   <productname>PostgreSQL</productname> implements the
-   <firstterm>SQL/JSON data model</firstterm>.
-   This model comprises sequences of items. Each item can hold SQL scalar
-   values, with an additional SQL/JSON null value, and composite data structures
-   that use JSON arrays and objects. The model is a formalization of the implied
-   data model in the JSON specification
-   <ulink url="https://datatracker.ietf.org/doc/html/rfc7159">RFC 7159</ulink>.
-  </para>
-
-  <para>
-   SQL/JSON allows you to handle JSON data alongside regular SQL data,
-   with transaction support, including:
-
-  <itemizedlist>
-   <listitem>
-    <para>
-     Uploading JSON data into the database and storing it in
-     regular SQL columns as character or binary strings.
-    </para>
-   </listitem>
-   <listitem>
-    <para>
-     Generating JSON objects and arrays from relational data.
-    </para>
-   </listitem>
-   <listitem>
-    <para>
-     Querying JSON data using SQL/JSON query functions and
-     SQL/JSON path language expressions.
-    </para>
-   </listitem>
-  </itemizedlist>
-  </para>
-
-  <para>
-   To learn more about the SQL/JSON standard, see
-   <xref linkend="sqltr-19075-6"/>. For details on JSON types
-   supported in <productname>PostgreSQL</productname>,
-   see <xref linkend="datatype-json"/>.
-  </para>
-
-  <sect2 id="functions-json-processing">
-   <title>Processing and Creating JSON Data</title>
-
-  <para>
-   <xref linkend="functions-json-op-table"/> shows the operators that
-   are available for use with JSON data types (see <xref
-   linkend="datatype-json"/>).
-   In addition, the usual comparison operators shown in <xref
-   linkend="functions-comparison-op-table"/> are available for
-   <type>jsonb</type>, though not for <type>json</type>.  The comparison
-   operators follow the ordering rules for B-tree operations outlined in
-   <xref linkend="json-indexing"/>.
-   See also <xref linkend="functions-aggregate"/> for the aggregate
-   function <function>json_agg</function> which aggregates record
-   values as JSON, the aggregate function
-   <function>json_object_agg</function> which aggregates pairs of values
-   into a JSON object, and their <type>jsonb</type> equivalents,
-   <function>jsonb_agg</function> and <function>jsonb_object_agg</function>.
-  </para>
-
-  <table id="functions-json-op-table">
-    <title><type>json</type> and <type>jsonb</type> Operators</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Operator
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>json</type> <literal>-&gt;</literal> <type>integer</type>
-        <returnvalue>json</returnvalue>
-       </para>
-       <para role="func_signature">
-        <type>jsonb</type> <literal>-&gt;</literal> <type>integer</type>
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Extracts <parameter>n</parameter>'th element of JSON array
-        (array elements are indexed from zero, but negative integers count
-        from the end).
-       </para>
-       <para>
-        <literal>'[{"a":"foo"},{"b":"bar"},{"c":"baz"}]'::json -&gt; 2</literal>
-        <returnvalue>{"c":"baz"}</returnvalue>
-       </para>
-       <para>
-        <literal>'[{"a":"foo"},{"b":"bar"},{"c":"baz"}]'::json -&gt; -3</literal>
-        <returnvalue>{"a":"foo"}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>json</type> <literal>-&gt;</literal> <type>text</type>
-        <returnvalue>json</returnvalue>
-       </para>
-       <para role="func_signature">
-        <type>jsonb</type> <literal>-&gt;</literal> <type>text</type>
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Extracts JSON object field with the given key.
-       </para>
-       <para>
-        <literal>'{"a": {"b":"foo"}}'::json -&gt; 'a'</literal>
-        <returnvalue>{"b":"foo"}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>json</type> <literal>-&gt;&gt;</literal> <type>integer</type>
-        <returnvalue>text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <type>jsonb</type> <literal>-&gt;&gt;</literal> <type>integer</type>
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Extracts <parameter>n</parameter>'th element of JSON array,
-        as <type>text</type>.
-       </para>
-       <para>
-        <literal>'[1,2,3]'::json -&gt;&gt; 2</literal>
-        <returnvalue>3</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>json</type> <literal>-&gt;&gt;</literal> <type>text</type>
-        <returnvalue>text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <type>jsonb</type> <literal>-&gt;&gt;</literal> <type>text</type>
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Extracts JSON object field with the given key, as <type>text</type>.
-       </para>
-       <para>
-        <literal>'{"a":1,"b":2}'::json -&gt;&gt; 'b'</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>json</type> <literal>#&gt;</literal> <type>text[]</type>
-        <returnvalue>json</returnvalue>
-       </para>
-       <para role="func_signature">
-        <type>jsonb</type> <literal>#&gt;</literal> <type>text[]</type>
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Extracts JSON sub-object at the specified path, where path elements
-        can be either field keys or array indexes.
-       </para>
-       <para>
-        <literal>'{"a": {"b": ["foo","bar"]}}'::json #&gt; '{a,b,1}'</literal>
-        <returnvalue>"bar"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>json</type> <literal>#&gt;&gt;</literal> <type>text[]</type>
-        <returnvalue>text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <type>jsonb</type> <literal>#&gt;&gt;</literal> <type>text[]</type>
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Extracts JSON sub-object at the specified path as <type>text</type>.
-       </para>
-       <para>
-        <literal>'{"a": {"b": ["foo","bar"]}}'::json #&gt;&gt; '{a,b,1}'</literal>
-        <returnvalue>bar</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <note>
-   <para>
-    The field/element/path extraction operators return NULL, rather than
-    failing, if the JSON input does not have the right structure to match
-    the request; for example if no such key or array element exists.
-   </para>
-  </note>
-
-  <para>
-   Some further operators exist only for <type>jsonb</type>, as shown
-   in <xref linkend="functions-jsonb-op-table"/>.
-   <xref linkend="json-indexing"/>
-   describes how these operators can be used to effectively search indexed
-   <type>jsonb</type> data.
-  </para>
-
-  <table id="functions-jsonb-op-table">
-    <title>Additional <type>jsonb</type> Operators</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Operator
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>jsonb</type> <literal>@&gt;</literal> <type>jsonb</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the first JSON value contain the second?
-        (See <xref linkend="json-containment"/> for details about containment.)
-       </para>
-       <para>
-        <literal>'{"a":1, "b":2}'::jsonb &#64;&gt; '{"b":2}'::jsonb</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>jsonb</type> <literal>&lt;@</literal> <type>jsonb</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the first JSON value contained in the second?
-       </para>
-       <para>
-        <literal>'{"b":2}'::jsonb &lt;@ '{"a":1, "b":2}'::jsonb</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>jsonb</type> <literal>?</literal> <type>text</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the text string exist as a top-level key or array element within
-        the JSON value?
-       </para>
-       <para>
-        <literal>'{"a":1, "b":2}'::jsonb ? 'b'</literal>
-        <returnvalue>t</returnvalue>
-       </para>
-       <para>
-        <literal>'["a", "b", "c"]'::jsonb ? 'b'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>jsonb</type> <literal>?|</literal> <type>text[]</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Do any of the strings in the text array exist as top-level keys or
-        array elements?
-       </para>
-       <para>
-        <literal>'{"a":1, "b":2, "c":3}'::jsonb ?| array['b', 'd']</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>jsonb</type> <literal>?&amp;</literal> <type>text[]</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Do all of the strings in the text array exist as top-level keys or
-        array elements?
-       </para>
-       <para>
-        <literal>'["a", "b", "c"]'::jsonb ?&amp; array['a', 'b']</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>jsonb</type> <literal>||</literal> <type>jsonb</type>
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Concatenates two <type>jsonb</type> values.
-        Concatenating two arrays generates an array containing all the
-        elements of each input.  Concatenating two objects generates an
-        object containing the union of their
-        keys, taking the second object's value when there are duplicate keys.
-        All other cases are treated by converting a non-array input into a
-        single-element array, and then proceeding as for two arrays.
-        Does not operate recursively: only the top-level array or object
-        structure is merged.
-       </para>
-       <para>
-        <literal>'["a", "b"]'::jsonb || '["a", "d"]'::jsonb</literal>
-        <returnvalue>["a", "b", "a", "d"]</returnvalue>
-       </para>
-       <para>
-        <literal>'{"a": "b"}'::jsonb || '{"c": "d"}'::jsonb</literal>
-        <returnvalue>{"a": "b", "c": "d"}</returnvalue>
-       </para>
-       <para>
-        <literal>'[1, 2]'::jsonb || '3'::jsonb</literal>
-        <returnvalue>[1, 2, 3]</returnvalue>
-       </para>
-       <para>
-        <literal>'{"a": "b"}'::jsonb || '42'::jsonb</literal>
-        <returnvalue>[{"a": "b"}, 42]</returnvalue>
-       </para>
-       <para>
-        To append an array to another array as a single entry, wrap it
-        in an additional layer of array, for example:
-       </para>
-       <para>
-        <literal>'[1, 2]'::jsonb || jsonb_build_array('[3, 4]'::jsonb)</literal>
-        <returnvalue>[1, 2, [3, 4]]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>jsonb</type> <literal>-</literal> <type>text</type>
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Deletes a key (and its value) from a JSON object, or matching string
-        value(s) from a JSON array.
-       </para>
-       <para>
-        <literal>'{"a": "b", "c": "d"}'::jsonb - 'a'</literal>
-        <returnvalue>{"c": "d"}</returnvalue>
-       </para>
-       <para>
-        <literal>'["a", "b", "c", "b"]'::jsonb - 'b'</literal>
-        <returnvalue>["a", "c"]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>jsonb</type> <literal>-</literal> <type>text[]</type>
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Deletes all matching keys or array elements from the left operand.
-       </para>
-       <para>
-        <literal>'{"a": "b", "c": "d"}'::jsonb - '{a,c}'::text[]</literal>
-        <returnvalue>{}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>jsonb</type> <literal>-</literal> <type>integer</type>
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Deletes the array element with specified index (negative
-        integers count from the end).  Throws an error if JSON value
-        is not an array.
-       </para>
-       <para>
-        <literal>'["a", "b"]'::jsonb - 1 </literal>
-        <returnvalue>["a"]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>jsonb</type> <literal>#-</literal> <type>text[]</type>
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Deletes the field or array element at the specified path, where path
-        elements can be either field keys or array indexes.
-       </para>
-       <para>
-        <literal>'["a", {"b":1}]'::jsonb #- '{1,b}'</literal>
-        <returnvalue>["a", {}]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>jsonb</type> <literal>@?</literal> <type>jsonpath</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does JSON path return any item for the specified JSON value?
-        (This is useful only with SQL-standard JSON path expressions, not
-        <link linkend="functions-sqljson-check-expressions">predicate check
-        expressions</link>, since those always return a value.)
-       </para>
-       <para>
-        <literal>'{"a":[1,2,3,4,5]}'::jsonb @? '$.a[*] ? (@ > 2)'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>jsonb</type> <literal>@@</literal> <type>jsonpath</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Returns the result of a JSON path predicate check for the
-        specified JSON value.
-        (This is useful only
-        with <link linkend="functions-sqljson-check-expressions">predicate
-        check expressions</link>, not SQL-standard JSON path expressions,
-        since it will return <literal>NULL</literal> if the path result is
-        not a single boolean value.)
-       </para>
-       <para>
-        <literal>'{"a":[1,2,3,4,5]}'::jsonb @@ '$.a[*] > 2'</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <note>
-   <para>
-    The <type>jsonpath</type> operators <literal>@?</literal>
-    and <literal>@@</literal> suppress the following errors: missing object
-    field or array element, unexpected JSON item type, datetime and numeric
-    errors.  The <type>jsonpath</type>-related functions described below can
-    also be told to suppress these types of errors.  This behavior might be
-    helpful when searching JSON document collections of varying structure.
-   </para>
-  </note>
-
-  <para>
-   <xref linkend="functions-json-creation-table"/> shows the functions that are
-   available for constructing <type>json</type> and <type>jsonb</type> values.
-   Some functions in this table have a <literal>RETURNING</literal> clause,
-   which specifies the data type returned.  It must be one of <type>json</type>,
-   <type>jsonb</type>, <type>bytea</type>, a character string type (<type>text</type>,
-   <type>char</type>, or <type>varchar</type>), or a type
-   that can be cast to <type>json</type>.
-   By default, the <type>json</type> type is returned.
-  </para>
-
-  <table id="functions-json-creation-table">
-    <title>JSON Creation Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_json</primary>
-        </indexterm>
-        <function>to_json</function> ( <type>anyelement</type> )
-        <returnvalue>json</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>to_jsonb</primary>
-        </indexterm>
-        <function>to_jsonb</function> ( <type>anyelement</type> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Converts any SQL value to <type>json</type> or <type>jsonb</type>.
-        Arrays and composites are converted recursively to arrays and
-        objects (multidimensional arrays become arrays of arrays in JSON).
-        Otherwise, if there is a cast from the SQL data type
-        to <type>json</type>, the cast function will be used to perform the
-        conversion;<footnote>
-         <para>
-          For example, the <xref linkend="hstore"/> extension has a cast
-          from <type>hstore</type> to <type>json</type>, so that
-          <type>hstore</type> values converted via the JSON creation functions
-          will be represented as JSON objects, not as primitive string values.
-         </para>
-        </footnote>
-        otherwise, a scalar JSON value is produced.  For any scalar other than
-        a number, a Boolean, or a null value, the text representation will be
-        used, with escaping as necessary to make it a valid JSON string value.
-       </para>
-       <para>
-        <literal>to_json('Fred said "Hi."'::text)</literal>
-        <returnvalue>"Fred said \"Hi.\""</returnvalue>
-       </para>
-       <para>
-        <literal>to_jsonb(row(42, 'Fred said "Hi."'::text))</literal>
-        <returnvalue>{"f1": 42, "f2": "Fred said \"Hi.\""}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_to_json</primary>
-        </indexterm>
-        <function>array_to_json</function> ( <type>anyarray</type> <optional>, <type>boolean</type> </optional> )
-        <returnvalue>json</returnvalue>
-       </para>
-       <para>
-        Converts an SQL array to a JSON array.  The behavior is the same
-        as <function>to_json</function> except that line feeds will be added
-        between top-level array elements if the optional boolean parameter is
-        true.
-       </para>
-       <para>
-        <literal>array_to_json('{{1,5},{99,100}}'::int[])</literal>
-        <returnvalue>[[1,5],[99,100]]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <!--
-           Note that this is barely legible in the output; it looks like a
-           salad of braces and brackets.  It would be better to split it out
-           in multiple lines, but that's surprisingly hard to do in a way that
-           matches in HTML and PDF output.  Other standard SQL/JSON functions
-           have the same problem.
-         -->
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm><primary>json_array</primary></indexterm>
-         <function>json_array</function> (
-         <optional> { <replaceable>value_expression</replaceable> <optional> <literal>FORMAT JSON</literal> </optional> } <optional>, ...</optional> </optional>
-         <optional> { <literal>NULL</literal> | <literal>ABSENT</literal> } <literal>ON NULL</literal> </optional>
-         <optional> <literal>RETURNING</literal> <replaceable>data_type</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional> </optional>)
-        </para>
-        <para role="func_signature">
-         <function>json_array</function> (
-         <optional> <replaceable>query_expression</replaceable> </optional>
-         <optional> <literal>RETURNING</literal> <replaceable>data_type</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional> </optional>)
-        </para>
-        <para>
-         Constructs a JSON array from either a series of
-         <replaceable>value_expression</replaceable> parameters or from the results
-         of <replaceable>query_expression</replaceable>,
-         which must be a SELECT query returning a single column. If
-         <literal>ABSENT ON NULL</literal> is specified, NULL values are ignored.
-         This is always the case if a
-         <replaceable>query_expression</replaceable> is used.
-        </para>
-        <para>
-         <literal>json_array(1,true,json '{"a":null}')</literal>
-         <returnvalue>[1, true, {"a":null}]</returnvalue>
-        </para>
-        <para>
-         <literal>json_array(SELECT * FROM (VALUES(1),(2)) t)</literal>
-         <returnvalue>[1, 2]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>row_to_json</primary>
-        </indexterm>
-        <function>row_to_json</function> ( <type>record</type> <optional>, <type>boolean</type> </optional> )
-        <returnvalue>json</returnvalue>
-       </para>
-       <para>
-        Converts an SQL composite value to a JSON object.  The behavior is the
-        same as <function>to_json</function> except that line feeds will be
-        added between top-level elements if the optional boolean parameter is
-        true.
-       </para>
-       <para>
-        <literal>row_to_json(row(1,'foo'))</literal>
-        <returnvalue>{"f1":1,"f2":"foo"}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_build_array</primary>
-        </indexterm>
-        <function>json_build_array</function> ( <literal>VARIADIC</literal> <type>"any"</type> )
-        <returnvalue>json</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_build_array</primary>
-        </indexterm>
-        <function>jsonb_build_array</function> ( <literal>VARIADIC</literal> <type>"any"</type> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Builds a possibly-heterogeneously-typed JSON array out of a variadic
-        argument list.  Each argument is converted as
-        per <function>to_json</function> or <function>to_jsonb</function>.
-       </para>
-       <para>
-        <literal>json_build_array(1, 2, 'foo', 4, 5)</literal>
-        <returnvalue>[1, 2, "foo", 4, 5]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_build_object</primary>
-        </indexterm>
-        <function>json_build_object</function> ( <literal>VARIADIC</literal> <type>"any"</type> )
-        <returnvalue>json</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_build_object</primary>
-        </indexterm>
-        <function>jsonb_build_object</function> ( <literal>VARIADIC</literal> <type>"any"</type> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Builds a JSON object out of a variadic argument list.  By convention,
-        the argument list consists of alternating keys and values.  Key
-        arguments are coerced to text; value arguments are converted as
-        per <function>to_json</function> or <function>to_jsonb</function>.
-       </para>
-       <para>
-        <literal>json_build_object('foo', 1, 2, row(3,'bar'))</literal>
-        <returnvalue>{"foo" : 1, "2" : {"f1":3,"f2":"bar"}}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-         <indexterm><primary>json_object</primary></indexterm>
-         <function>json_object</function> (
-         <optional> { <replaceable>key_expression</replaceable> { <literal>VALUE</literal> | ':' }
-          <replaceable>value_expression</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional> }<optional>, ...</optional> </optional>
-         <optional> { <literal>NULL</literal> | <literal>ABSENT</literal> } <literal>ON NULL</literal> </optional>
-         <optional> { <literal>WITH</literal> | <literal>WITHOUT</literal> } <literal>UNIQUE</literal> <optional> <literal>KEYS</literal> </optional> </optional>
-         <optional> <literal>RETURNING</literal> <replaceable>data_type</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional> </optional>)
-        </para>
-        <para>
-         Constructs a JSON object of all the key/value pairs given,
-         or an empty object if none are given.
-         <replaceable>key_expression</replaceable> is a scalar expression
-         defining the <acronym>JSON</acronym> key, which is
-         converted to the <type>text</type> type.
-         It cannot be <literal>NULL</literal> nor can it
-         belong to a type that has a cast to the <type>json</type> type.
-         If <literal>WITH UNIQUE KEYS</literal> is specified, there must not
-         be any duplicate <replaceable>key_expression</replaceable>.
-         Any pair for which the <replaceable>value_expression</replaceable>
-         evaluates to <literal>NULL</literal> is omitted from the output
-         if <literal>ABSENT ON NULL</literal> is specified;
-         if <literal>NULL ON NULL</literal> is specified or the clause
-         omitted, the key is included with value <literal>NULL</literal>.
-        </para>
-        <para>
-         <literal>json_object('code' VALUE 'P123', 'title': 'Jaws')</literal>
-         <returnvalue>{"code" : "P123", "title" : "Jaws"}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_object</primary>
-        </indexterm>
-        <function>json_object</function> ( <type>text[]</type> )
-        <returnvalue>json</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_object</primary>
-        </indexterm>
-        <function>jsonb_object</function> ( <type>text[]</type> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Builds a JSON object out of a text array.  The array must have either
-        exactly one dimension with an even number of members, in which case
-        they are taken as alternating key/value pairs, or two dimensions
-        such that each inner array has exactly two elements, which
-        are taken as a key/value pair.  All values are converted to JSON
-        strings.
-       </para>
-       <para>
-        <literal>json_object('{a, 1, b, "def", c, 3.5}')</literal>
-        <returnvalue>{"a" : "1", "b" : "def", "c" : "3.5"}</returnvalue>
-       </para>
-        <para><literal>json_object('{{a, 1}, {b, "def"}, {c, 3.5}}')</literal>
-        <returnvalue>{"a" : "1", "b" : "def", "c" : "3.5"}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>json_object</function> ( <parameter>keys</parameter> <type>text[]</type>, <parameter>values</parameter> <type>text[]</type> )
-        <returnvalue>json</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>jsonb_object</function> ( <parameter>keys</parameter> <type>text[]</type>, <parameter>values</parameter> <type>text[]</type> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        This form of <function>json_object</function> takes keys and values
-        pairwise from separate text arrays.  Otherwise it is identical to
-        the one-argument form.
-       </para>
-       <para>
-        <literal>json_object('{a,b}', '{1,2}')</literal>
-        <returnvalue>{"a": "1", "b": "2"}</returnvalue>
-       </para></entry>
-      </row>
-      <row>
-       <entry role="func_table_entry">
-        <para role="func_signature">
-         <indexterm><primary>json constructor</primary></indexterm>
-         <function>json</function> (
-         <replaceable>expression</replaceable>
-         <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional></optional>
-         <optional> { <literal>WITH</literal> | <literal>WITHOUT</literal> } <literal>UNIQUE</literal> <optional> <literal>KEYS</literal> </optional></optional> )
-         <returnvalue>json</returnvalue>
-        </para>
-        <para>
-         Converts a given expression specified as <type>text</type> or
-         <type>bytea</type> string (in UTF8 encoding) into a JSON
-         value.  If <replaceable>expression</replaceable> is NULL, an
-         <acronym>SQL</acronym> null value is returned.
-         If <literal>WITH UNIQUE</literal> is specified, the
-         <replaceable>expression</replaceable> must not contain any duplicate
-         object keys.
-        </para>
-        <para>
-         <literal>json('{"a":123, "b":[true,"foo"], "a":"bar"}')</literal>
-         <returnvalue>{"a":123, "b":[true,"foo"], "a":"bar"}</returnvalue>
-        </para>
-       </entry>
-      </row>
-      <row>
-       <entry role="func_table_entry">
-        <para role="func_signature">
-        <indexterm><primary>json_scalar</primary></indexterm>
-        <function>json_scalar</function> ( <replaceable>expression</replaceable> )
-       </para>
-       <para>
-        Converts a given SQL scalar value into a JSON scalar value.
-        If the input is NULL, an <acronym>SQL</acronym> null is returned. If
-        the input is number or a boolean value, a corresponding JSON number
-        or boolean value is returned. For any other value, a JSON string is
-        returned.
-       </para>
-       <para>
-        <literal>json_scalar(123.45)</literal>
-        <returnvalue>123.45</returnvalue>
-       </para>
-       <para>
-        <literal>json_scalar(CURRENT_TIMESTAMP)</literal>
-        <returnvalue>"2022-05-10T10:51:04.62128-04:00"</returnvalue>
-      </para></entry>
-     </row>
-     <row>
-      <entry role="func_table_entry">
-       <para role="func_signature">
-        <function>json_serialize</function> (
-        <replaceable>expression</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional>
-        <optional> <literal>RETURNING</literal> <replaceable>data_type</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional> </optional> )
-       </para>
-       <para>
-        Converts an SQL/JSON expression into a character or binary string. The
-        <replaceable>expression</replaceable> can be of any JSON type, any
-        character string type, or <type>bytea</type> in UTF8 encoding.
-        The returned type used in <literal> RETURNING</literal> can be any
-        character string type or <type>bytea</type>. The default is
-        <type>text</type>.
-       </para>
-       <para>
-        <literal>json_serialize('{ "a" : 1 } ' RETURNING bytea)</literal>
-        <returnvalue>\x7b20226122203a2031207d20</returnvalue>
-      </para></entry>
-     </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <para>
-   <xref linkend="functions-sqljson-misc" /> details SQL/JSON
-   facilities for testing JSON.
-  </para>
-
-  <table id="functions-sqljson-misc">
-   <title>SQL/JSON Testing Functions</title>
-   <tgroup cols="1">
-    <thead>
-     <row>
-      <entry role="func_table_entry"><para role="func_signature">
-        Function signature
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-      </para></entry>
-     </row>
-    </thead>
-    <tbody>
-     <row>
-      <entry role="func_table_entry"><para role="func_signature">
-        <indexterm><primary>IS JSON</primary></indexterm>
-        <replaceable>expression</replaceable> <literal>IS</literal> <optional> <literal>NOT</literal> </optional> <literal>JSON</literal>
-        <optional> { <literal>VALUE</literal> | <literal>SCALAR</literal> | <literal>ARRAY</literal> | <literal>OBJECT</literal> } </optional>
-        <optional> { <literal>WITH</literal> | <literal>WITHOUT</literal> } <literal>UNIQUE</literal> <optional> <literal>KEYS</literal> </optional> </optional>
-       </para>
-       <para>
-        This predicate tests whether <replaceable>expression</replaceable> can be
-        parsed as JSON, possibly of a specified type.
-        If <literal>SCALAR</literal> or <literal>ARRAY</literal> or
-        <literal>OBJECT</literal> is specified, the
-        test is whether or not the JSON is of that particular type. If
-        <literal>WITH UNIQUE KEYS</literal> is specified, then any object in the
-        <replaceable>expression</replaceable> is also tested to see if it
-        has duplicate keys.
-       </para>
-       <para>
-<programlisting>
-SELECT js,
-  js IS JSON "json?",
-  js IS JSON SCALAR "scalar?",
-  js IS JSON OBJECT "object?",
-  js IS JSON ARRAY "array?"
-FROM (VALUES
-      ('123'), ('"abc"'), ('{"a": "b"}'), ('[1,2]'),('abc')) foo(js);
-     js     | json? | scalar? | object? | array?
-------------+-------+---------+---------+--------
- 123        | t     | t       | f       | f
- "abc"      | t     | t       | f       | f
- {"a": "b"} | t     | f       | t       | f
- [1,2]      | t     | f       | f       | t
- abc        | f     | f       | f       | f
-</programlisting>
-       </para>
-       <para>
-<programlisting>
-SELECT js,
-  js IS JSON OBJECT "object?",
-  js IS JSON ARRAY "array?",
-  js IS JSON ARRAY WITH UNIQUE KEYS "array w. UK?",
-  js IS JSON ARRAY WITHOUT UNIQUE KEYS "array w/o UK?"
-FROM (VALUES ('[{"a":"1"},
- {"b":"2","b":"3"}]')) foo(js);
--[ RECORD 1 ]-+--------------------
-js            | [{"a":"1"},        +
-              |  {"b":"2","b":"3"}]
-object?       | f
-array?        | t
-array w. UK?  | f
-array w/o UK? | t
-</programlisting>
-      </para></entry>
-     </row>
-    </tbody>
-   </tgroup>
-  </table>
-
-  <para>
-   <xref linkend="functions-json-processing-table"/> shows the functions that
-   are available for processing <type>json</type> and <type>jsonb</type> values.
-  </para>
-
-  <table id="functions-json-processing-table">
-    <title>JSON Processing Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_array_elements</primary>
-        </indexterm>
-        <function>json_array_elements</function> ( <type>json</type> )
-        <returnvalue>setof json</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_array_elements</primary>
-        </indexterm>
-        <function>jsonb_array_elements</function> ( <type>jsonb</type> )
-        <returnvalue>setof jsonb</returnvalue>
-       </para>
-       <para>
-        Expands the top-level JSON array into a set of JSON values.
-       </para>
-       <para>
-        <literal>select * from json_array_elements('[1,true, [2,false]]')</literal>
-        <returnvalue></returnvalue>
-<programlisting>
-   value
------------
- 1
- true
- [2,false]
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_array_elements_text</primary>
-        </indexterm>
-        <function>json_array_elements_text</function> ( <type>json</type> )
-        <returnvalue>setof text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_array_elements_text</primary>
-        </indexterm>
-        <function>jsonb_array_elements_text</function> ( <type>jsonb</type> )
-        <returnvalue>setof text</returnvalue>
-       </para>
-       <para>
-        Expands the top-level JSON array into a set of <type>text</type> values.
-       </para>
-       <para>
-        <literal>select * from json_array_elements_text('["foo", "bar"]')</literal>
-        <returnvalue></returnvalue>
-<programlisting>
-   value
------------
- foo
- bar
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_array_length</primary>
-        </indexterm>
-        <function>json_array_length</function> ( <type>json</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_array_length</primary>
-        </indexterm>
-        <function>jsonb_array_length</function> ( <type>jsonb</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the number of elements in the top-level JSON array.
-       </para>
-       <para>
-        <literal>json_array_length('[1,2,3,{"f1":1,"f2":[5,6]},4]')</literal>
-        <returnvalue>5</returnvalue>
-       </para>
-       <para>
-        <literal>jsonb_array_length('[]')</literal>
-        <returnvalue>0</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_each</primary>
-        </indexterm>
-        <function>json_each</function> ( <type>json</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>key</parameter> <type>text</type>,
-        <parameter>value</parameter> <type>json</type> )
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_each</primary>
-        </indexterm>
-        <function>jsonb_each</function> ( <type>jsonb</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>key</parameter> <type>text</type>,
-        <parameter>value</parameter> <type>jsonb</type> )
-       </para>
-       <para>
-        Expands the top-level JSON object into a set of key/value pairs.
-       </para>
-       <para>
-        <literal>select * from json_each('{"a":"foo", "b":"bar"}')</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- key | value
------+-------
- a   | "foo"
- b   | "bar"
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_each_text</primary>
-        </indexterm>
-        <function>json_each_text</function> ( <type>json</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>key</parameter> <type>text</type>,
-        <parameter>value</parameter> <type>text</type> )
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_each_text</primary>
-        </indexterm>
-        <function>jsonb_each_text</function> ( <type>jsonb</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>key</parameter> <type>text</type>,
-        <parameter>value</parameter> <type>text</type> )
-       </para>
-       <para>
-        Expands the top-level JSON object into a set of key/value pairs.
-        The returned <parameter>value</parameter>s will be of
-        type <type>text</type>.
-       </para>
-       <para>
-        <literal>select * from json_each_text('{"a":"foo", "b":"bar"}')</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- key | value
------+-------
- a   | foo
- b   | bar
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_extract_path</primary>
-        </indexterm>
-        <function>json_extract_path</function> ( <parameter>from_json</parameter> <type>json</type>, <literal>VARIADIC</literal> <parameter>path_elems</parameter> <type>text[]</type> )
-        <returnvalue>json</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_extract_path</primary>
-        </indexterm>
-        <function>jsonb_extract_path</function> ( <parameter>from_json</parameter> <type>jsonb</type>, <literal>VARIADIC</literal> <parameter>path_elems</parameter> <type>text[]</type> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Extracts JSON sub-object at the specified path.
-        (This is functionally equivalent to the <literal>#&gt;</literal>
-        operator, but writing the path out as a variadic list can be more
-        convenient in some cases.)
-       </para>
-       <para>
-        <literal>json_extract_path('{"f2":{"f3":1},"f4":{"f5":99,"f6":"foo"}}', 'f4', 'f6')</literal>
-        <returnvalue>"foo"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_extract_path_text</primary>
-        </indexterm>
-        <function>json_extract_path_text</function> ( <parameter>from_json</parameter> <type>json</type>, <literal>VARIADIC</literal> <parameter>path_elems</parameter> <type>text[]</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_extract_path_text</primary>
-        </indexterm>
-        <function>jsonb_extract_path_text</function> ( <parameter>from_json</parameter> <type>jsonb</type>, <literal>VARIADIC</literal> <parameter>path_elems</parameter> <type>text[]</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Extracts JSON sub-object at the specified path as <type>text</type>.
-        (This is functionally equivalent to the <literal>#&gt;&gt;</literal>
-        operator.)
-       </para>
-       <para>
-        <literal>json_extract_path_text('{"f2":{"f3":1},"f4":{"f5":99,"f6":"foo"}}', 'f4', 'f6')</literal>
-        <returnvalue>foo</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_object_keys</primary>
-        </indexterm>
-        <function>json_object_keys</function> ( <type>json</type> )
-        <returnvalue>setof text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_object_keys</primary>
-        </indexterm>
-        <function>jsonb_object_keys</function> ( <type>jsonb</type> )
-        <returnvalue>setof text</returnvalue>
-       </para>
-       <para>
-        Returns the set of keys in the top-level JSON object.
-       </para>
-       <para>
-        <literal>select * from json_object_keys('{"f1":"abc","f2":{"f3":"a", "f4":"b"}}')</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- json_object_keys
-------------------
- f1
- f2
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_populate_record</primary>
-        </indexterm>
-        <function>json_populate_record</function> ( <parameter>base</parameter> <type>anyelement</type>, <parameter>from_json</parameter> <type>json</type> )
-        <returnvalue>anyelement</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_populate_record</primary>
-        </indexterm>
-        <function>jsonb_populate_record</function> ( <parameter>base</parameter> <type>anyelement</type>, <parameter>from_json</parameter> <type>jsonb</type> )
-        <returnvalue>anyelement</returnvalue>
-       </para>
-       <para>
-        Expands the top-level JSON object to a row having the composite type
-        of the <parameter>base</parameter> argument.  The JSON object
-        is scanned for fields whose names match column names of the output row
-        type, and their values are inserted into those columns of the output.
-        (Fields that do not correspond to any output column name are ignored.)
-        In typical use, the value of <parameter>base</parameter> is just
-        <literal>NULL</literal>, which means that any output columns that do
-        not match any object field will be filled with nulls.  However,
-        if <parameter>base</parameter> isn't <literal>NULL</literal> then
-        the values it contains will be used for unmatched columns.
-       </para>
-       <para>
-        To convert a JSON value to the SQL type of an output column, the
-        following rules are applied in sequence:
-        <itemizedlist spacing="compact">
-         <listitem>
-          <para>
-           A JSON null value is converted to an SQL null in all cases.
-          </para>
-         </listitem>
-         <listitem>
-          <para>
-           If the output column is of type <type>json</type>
-           or <type>jsonb</type>, the JSON value is just reproduced exactly.
-          </para>
-         </listitem>
-         <listitem>
-          <para>
-           If the output column is a composite (row) type, and the JSON value
-           is a JSON object, the fields of the object are converted to columns
-           of the output row type by recursive application of these rules.
-          </para>
-         </listitem>
-         <listitem>
-          <para>
-           Likewise, if the output column is an array type and the JSON value
-           is a JSON array, the elements of the JSON array are converted to
-           elements of the output array by recursive application of these
-           rules.
-          </para>
-         </listitem>
-         <listitem>
-          <para>
-           Otherwise, if the JSON value is a string, the contents of the
-           string are fed to the input conversion function for the column's
-           data type.
-          </para>
-         </listitem>
-         <listitem>
-          <para>
-           Otherwise, the ordinary text representation of the JSON value is
-           fed to the input conversion function for the column's data type.
-          </para>
-         </listitem>
-        </itemizedlist>
-       </para>
-       <para>
-        While the example below uses a constant JSON value, typical use would
-        be to reference a <type>json</type> or <type>jsonb</type> column
-        laterally from another table in the query's <literal>FROM</literal>
-        clause.  Writing <function>json_populate_record</function> in
-        the <literal>FROM</literal> clause is good practice, since all of the
-        extracted columns are available for use without duplicate function
-        calls.
-       </para>
-       <para>
-        <literal>create type subrowtype as (d int, e text);</literal>
-        <literal>create type myrowtype as (a int, b text[], c subrowtype);</literal>
-       </para>
-       <para>
-        <literal>select * from json_populate_record(null::myrowtype,
-         '{"a": 1, "b": ["2", "a b"], "c": {"d": 4, "e": "a  b c"}, "x": "foo"}')</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- a |   b       |      c
----+-----------+-------------
- 1 | {2,"a b"} | (4,"a b c")
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>jsonb_populate_record_valid</primary>
-        </indexterm>
-        <function>jsonb_populate_record_valid</function> ( <parameter>base</parameter> <type>anyelement</type>, <parameter>from_json</parameter> <type>json</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Function for testing <function>jsonb_populate_record</function>.  Returns
-        <literal>true</literal> if the input <function>jsonb_populate_record</function>
-        would finish without an error for the given input JSON object; that is, it's
-        valid input, <literal>false</literal> otherwise.
-       </para>
-       <para>
-        <literal>create type jsb_char2 as (a char(2));</literal>
-       </para>
-       <para>
-        <literal>select jsonb_populate_record_valid(NULL::jsb_char2, '{"a": "aaa"}');</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- jsonb_populate_record_valid
------------------------------
- f
-(1 row)
-</programlisting>
-
-        <literal>select * from jsonb_populate_record(NULL::jsb_char2, '{"a": "aaa"}') q;</literal>
-        <returnvalue></returnvalue>
-<programlisting>
-ERROR:  value too long for type character(2)
-</programlisting>
-        <literal>select jsonb_populate_record_valid(NULL::jsb_char2, '{"a": "aa"}');</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- jsonb_populate_record_valid
------------------------------
- t
-(1 row)
-</programlisting>
-
-        <literal>select * from jsonb_populate_record(NULL::jsb_char2, '{"a": "aa"}') q;</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- a
-----
- aa
-(1 row)
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_populate_recordset</primary>
-        </indexterm>
-        <function>json_populate_recordset</function> ( <parameter>base</parameter> <type>anyelement</type>, <parameter>from_json</parameter> <type>json</type> )
-        <returnvalue>setof anyelement</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_populate_recordset</primary>
-        </indexterm>
-        <function>jsonb_populate_recordset</function> ( <parameter>base</parameter> <type>anyelement</type>, <parameter>from_json</parameter> <type>jsonb</type> )
-        <returnvalue>setof anyelement</returnvalue>
-       </para>
-       <para>
-        Expands the top-level JSON array of objects to a set of rows having
-        the composite type of the <parameter>base</parameter> argument.
-        Each element of the JSON array is processed as described above
-        for <function>json[b]_populate_record</function>.
-       </para>
-       <para>
-        <literal>create type twoints as (a int, b int);</literal>
-       </para>
-       <para>
-        <literal>select * from json_populate_recordset(null::twoints, '[{"a":1,"b":2}, {"a":3,"b":4}]')</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- a | b
----+---
- 1 | 2
- 3 | 4
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_to_record</primary>
-        </indexterm>
-        <function>json_to_record</function> ( <type>json</type> )
-        <returnvalue>record</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_to_record</primary>
-        </indexterm>
-        <function>jsonb_to_record</function> ( <type>jsonb</type> )
-        <returnvalue>record</returnvalue>
-       </para>
-       <para>
-        Expands the top-level JSON object to a row having the composite type
-        defined by an <literal>AS</literal> clause.  (As with all functions
-        returning <type>record</type>, the calling query must explicitly
-        define the structure of the record with an <literal>AS</literal>
-        clause.)  The output record is filled from fields of the JSON object,
-        in the same way as described above
-        for <function>json[b]_populate_record</function>.  Since there is no
-        input record value, unmatched columns are always filled with nulls.
-       </para>
-       <para>
-        <literal>create type myrowtype as (a int, b text);</literal>
-       </para>
-       <para>
-        <literal>select * from json_to_record('{"a":1,"b":[1,2,3],"c":[1,2,3],"e":"bar","r": {"a": 123, "b": "a b c"}}') as x(a int, b text, c int[], d text, r myrowtype)</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- a |    b    |    c    | d |       r
----+---------+---------+---+---------------
- 1 | [1,2,3] | {1,2,3} |   | (123,"a b c")
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_to_recordset</primary>
-        </indexterm>
-        <function>json_to_recordset</function> ( <type>json</type> )
-        <returnvalue>setof record</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_to_recordset</primary>
-        </indexterm>
-        <function>jsonb_to_recordset</function> ( <type>jsonb</type> )
-        <returnvalue>setof record</returnvalue>
-       </para>
-       <para>
-        Expands the top-level JSON array of objects to a set of rows having
-        the composite type defined by an <literal>AS</literal> clause.  (As
-        with all functions returning <type>record</type>, the calling query
-        must explicitly define the structure of the record with
-        an <literal>AS</literal> clause.)  Each element of the JSON array is
-        processed as described above
-        for <function>json[b]_populate_record</function>.
-       </para>
-       <para>
-        <literal>select * from json_to_recordset('[{"a":1,"b":"foo"}, {"a":"2","c":"bar"}]') as x(a int, b text)</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- a |  b
----+-----
- 1 | foo
- 2 |
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>jsonb_set</primary>
-        </indexterm>
-        <function>jsonb_set</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>text[]</type>, <parameter>new_value</parameter> <type>jsonb</type> <optional>, <parameter>create_if_missing</parameter> <type>boolean</type> </optional> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Returns <parameter>target</parameter>
-        with the item designated by <parameter>path</parameter>
-        replaced by <parameter>new_value</parameter>, or with
-        <parameter>new_value</parameter> added if
-        <parameter>create_if_missing</parameter> is true (which is the
-        default) and the item designated by <parameter>path</parameter>
-        does not exist.
-        All earlier steps in the path must exist, or
-        the <parameter>target</parameter> is returned unchanged.
-        As with the path oriented operators, negative integers that
-        appear in the <parameter>path</parameter> count from the end
-        of JSON arrays.
-        If the last path step is an array index that is out of range,
-        and <parameter>create_if_missing</parameter> is true, the new
-        value is added at the beginning of the array if the index is negative,
-        or at the end of the array if it is positive.
-       </para>
-       <para>
-        <literal>jsonb_set('[{"f1":1,"f2":null},2,null,3]', '{0,f1}', '[2,3,4]', false)</literal>
-        <returnvalue>[{"f1": [2, 3, 4], "f2": null}, 2, null, 3]</returnvalue>
-       </para>
-       <para>
-        <literal>jsonb_set('[{"f1":1,"f2":null},2]', '{0,f3}', '[2,3,4]')</literal>
-        <returnvalue>[{"f1": 1, "f2": null, "f3": [2, 3, 4]}, 2]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>jsonb_set_lax</primary>
-        </indexterm>
-        <function>jsonb_set_lax</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>text[]</type>, <parameter>new_value</parameter> <type>jsonb</type> <optional>, <parameter>create_if_missing</parameter> <type>boolean</type> <optional>, <parameter>null_value_treatment</parameter> <type>text</type> </optional></optional> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        If <parameter>new_value</parameter> is not <literal>NULL</literal>,
-        behaves identically to <literal>jsonb_set</literal>. Otherwise behaves
-        according to the value
-        of <parameter>null_value_treatment</parameter> which must be one
-        of <literal>'raise_exception'</literal>,
-        <literal>'use_json_null'</literal>, <literal>'delete_key'</literal>, or
-        <literal>'return_target'</literal>. The default is
-        <literal>'use_json_null'</literal>.
-       </para>
-       <para>
-        <literal>jsonb_set_lax('[{"f1":1,"f2":null},2,null,3]', '{0,f1}', null)</literal>
-        <returnvalue>[{"f1": null, "f2": null}, 2, null, 3]</returnvalue>
-       </para>
-       <para>
-        <literal>jsonb_set_lax('[{"f1":99,"f2":null},2]', '{0,f3}', null, true, 'return_target')</literal>
-        <returnvalue>[{"f1": 99, "f2": null}, 2]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>jsonb_insert</primary>
-        </indexterm>
-        <function>jsonb_insert</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>text[]</type>, <parameter>new_value</parameter> <type>jsonb</type> <optional>, <parameter>insert_after</parameter> <type>boolean</type> </optional> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Returns <parameter>target</parameter>
-        with <parameter>new_value</parameter> inserted.  If the item
-        designated by the <parameter>path</parameter> is an array
-        element, <parameter>new_value</parameter> will be inserted before
-        that item if <parameter>insert_after</parameter> is false (which
-        is the default), or after it
-        if <parameter>insert_after</parameter> is true.  If the item
-        designated by the <parameter>path</parameter> is an object
-        field, <parameter>new_value</parameter> will be inserted only if
-        the object does not already contain that key.
-        All earlier steps in the path must exist, or
-        the <parameter>target</parameter> is returned unchanged.
-        As with the path oriented operators, negative integers that
-        appear in the <parameter>path</parameter> count from the end
-        of JSON arrays.
-        If the last path step is an array index that is out of range, the new
-        value is added at the beginning of the array if the index is negative,
-        or at the end of the array if it is positive.
-       </para>
-       <para>
-        <literal>jsonb_insert('{"a": [0,1,2]}', '{a, 1}', '"new_value"')</literal>
-        <returnvalue>{"a": [0, "new_value", 1, 2]}</returnvalue>
-       </para>
-       <para>
-        <literal>jsonb_insert('{"a": [0,1,2]}', '{a, 1}', '"new_value"', true)</literal>
-        <returnvalue>{"a": [0, 1, "new_value", 2]}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_strip_nulls</primary>
-        </indexterm>
-        <function>json_strip_nulls</function> ( <parameter>target</parameter> <type>json</type> <optional>,<parameter>strip_in_arrays</parameter> <type>boolean</type> </optional> )
-        <returnvalue>json</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_strip_nulls</primary>
-        </indexterm>
-        <function>jsonb_strip_nulls</function> ( <parameter>target</parameter> <type>jsonb</type> <optional>,<parameter>strip_in_arrays</parameter> <type>boolean</type> </optional> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Deletes all object fields that have null values from the given JSON
-        value, recursively.
-        If <parameter>strip_in_arrays</parameter> is true (the default is false),
-        null array elements are also stripped.
-        Otherwise they are not stripped. Bare null values are never stripped.
-       </para>
-       <para>
-        <literal>json_strip_nulls('[{"f1":1, "f2":null}, 2, null, 3]')</literal>
-        <returnvalue>[{"f1":1},2,null,3]</returnvalue>
-       </para>
-       <para>
-        <literal>jsonb_strip_nulls('[1,2,null,3,4]', true);</literal>
-        <returnvalue>[1,2,3,4]</returnvalue>
-       </para>
-       </entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>jsonb_path_exists</primary>
-        </indexterm>
-        <function>jsonb_path_exists</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Checks whether the JSON path returns any item for the specified JSON
-        value.
-        (This is useful only with SQL-standard JSON path expressions, not
-        <link linkend="functions-sqljson-check-expressions">predicate check
-        expressions</link>, since those always return a value.)
-        If the <parameter>vars</parameter> argument is specified, it must
-        be a JSON object, and its fields provide named values to be
-        substituted into the <type>jsonpath</type> expression.
-        If the <parameter>silent</parameter> argument is specified and
-        is <literal>true</literal>, the function suppresses the same errors
-        as the <literal>@?</literal> and <literal>@@</literal> operators do.
-       </para>
-       <para>
-        <literal>jsonb_path_exists('{"a":[1,2,3,4,5]}', '$.a[*] ? (@ >= $min &amp;&amp; @ &lt;= $max)', '{"min":2, "max":4}')</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>jsonb_path_match</primary>
-        </indexterm>
-        <function>jsonb_path_match</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Returns the SQL boolean result of a JSON path predicate check
-        for the specified JSON value.
-        (This is useful only
-        with <link linkend="functions-sqljson-check-expressions">predicate
-        check expressions</link>, not SQL-standard JSON path expressions,
-        since it will either fail or return <literal>NULL</literal> if the
-        path result is not a single boolean value.)
-        The optional <parameter>vars</parameter>
-        and <parameter>silent</parameter> arguments act the same as
-        for <function>jsonb_path_exists</function>.
-       </para>
-       <para>
-        <literal>jsonb_path_match('{"a":[1,2,3,4,5]}', 'exists($.a[*] ? (@ >= $min &amp;&amp; @ &lt;= $max))', '{"min":2, "max":4}')</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>jsonb_path_query</primary>
-        </indexterm>
-        <function>jsonb_path_query</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
-        <returnvalue>setof jsonb</returnvalue>
-       </para>
-       <para>
-        Returns all JSON items returned by the JSON path for the specified
-        JSON value.
-        For SQL-standard JSON path expressions it returns the JSON
-        values selected from <parameter>target</parameter>.
-        For <link linkend="functions-sqljson-check-expressions">predicate
-        check expressions</link> it returns the result of the predicate
-        check: <literal>true</literal>, <literal>false</literal>,
-        or <literal>null</literal>.
-        The optional <parameter>vars</parameter>
-        and <parameter>silent</parameter> arguments act the same as
-        for <function>jsonb_path_exists</function>.
-       </para>
-       <para>
-        <literal>select * from jsonb_path_query('{"a":[1,2,3,4,5]}', '$.a[*] ? (@ >= $min &amp;&amp; @ &lt;= $max)', '{"min":2, "max":4}')</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- jsonb_path_query
-------------------
- 2
- 3
- 4
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>jsonb_path_query_array</primary>
-        </indexterm>
-        <function>jsonb_path_query_array</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Returns all JSON items returned by the JSON path for the specified
-        JSON value, as a JSON array.
-        The parameters are the same as
-        for <function>jsonb_path_query</function>.
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('{"a":[1,2,3,4,5]}', '$.a[*] ? (@ >= $min &amp;&amp; @ &lt;= $max)', '{"min":2, "max":4}')</literal>
-        <returnvalue>[2, 3, 4]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>jsonb_path_query_first</primary>
-        </indexterm>
-        <function>jsonb_path_query_first</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Returns the first JSON item returned by the JSON path for the
-        specified JSON value, or <literal>NULL</literal> if there are no
-        results.
-        The parameters are the same as
-        for <function>jsonb_path_query</function>.
-       </para>
-       <para>
-        <literal>jsonb_path_query_first('{"a":[1,2,3,4,5]}', '$.a[*] ? (@ >= $min &amp;&amp; @ &lt;= $max)', '{"min":2, "max":4}')</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>jsonb_path_exists_tz</primary>
-        </indexterm>
-        <function>jsonb_path_exists_tz</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_path_match_tz</primary>
-        </indexterm>
-        <function>jsonb_path_match_tz</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_path_query_tz</primary>
-        </indexterm>
-        <function>jsonb_path_query_tz</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
-        <returnvalue>setof jsonb</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_path_query_array_tz</primary>
-        </indexterm>
-        <function>jsonb_path_query_array_tz</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_path_query_first_tz</primary>
-        </indexterm>
-        <function>jsonb_path_query_first_tz</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        These functions act like their counterparts described above without
-        the <literal>_tz</literal> suffix, except that these functions support
-        comparisons of date/time values that require timezone-aware
-        conversions.  The example below requires interpretation of the
-        date-only value <literal>2015-08-02</literal> as a timestamp with time
-        zone, so the result depends on the current
-        <xref linkend="guc-timezone"/> setting.  Due to this dependency, these
-        functions are marked as stable, which means these functions cannot be
-        used in indexes.  Their counterparts are immutable, and so can be used
-        in indexes; but they will throw errors if asked to make such
-        comparisons.
-       </para>
-       <para>
-        <literal>jsonb_path_exists_tz('["2015-08-01 12:00:00-05"]', '$[*] ? (@.datetime() &lt; "2015-08-02".datetime())')</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>jsonb_pretty</primary>
-        </indexterm>
-        <function>jsonb_pretty</function> ( <type>jsonb</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts the given JSON value to pretty-printed, indented text.
-       </para>
-       <para>
-        <literal>jsonb_pretty('[{"f1":1,"f2":null}, 2]')</literal>
-        <returnvalue></returnvalue>
-<programlisting>
-[
-    {
-        "f1": 1,
-        "f2": null
-    },
-    2
-]
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_typeof</primary>
-        </indexterm>
-        <function>json_typeof</function> ( <type>json</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_typeof</primary>
-        </indexterm>
-        <function>jsonb_typeof</function> ( <type>jsonb</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the type of the top-level JSON value as a text string.
-        Possible types are
-        <literal>object</literal>, <literal>array</literal>,
-        <literal>string</literal>, <literal>number</literal>,
-        <literal>boolean</literal>, and <literal>null</literal>.
-        (The <literal>null</literal> result should not be confused
-        with an SQL NULL; see the examples.)
-       </para>
-       <para>
-        <literal>json_typeof('-123.4')</literal>
-        <returnvalue>number</returnvalue>
-       </para>
-       <para>
-        <literal>json_typeof('null'::json)</literal>
-        <returnvalue>null</returnvalue>
-       </para>
-       <para>
-        <literal>json_typeof(NULL::json) IS NULL</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
- </sect2>
-
- <sect2 id="functions-sqljson-path">
-  <title>The SQL/JSON Path Language</title>
-
-  <indexterm zone="functions-sqljson-path">
-   <primary>SQL/JSON path language</primary>
-  </indexterm>
-
-  <para>
-   SQL/JSON path expressions specify item(s) to be retrieved
-   from a JSON value, similarly to XPath expressions used
-   for access to XML content. In <productname>PostgreSQL</productname>,
-   path expressions are implemented as the <type>jsonpath</type>
-   data type and can use any elements described in
-   <xref linkend="datatype-jsonpath"/>.
-  </para>
-
-  <para>
-   JSON query functions and operators
-   pass the provided path expression to the <firstterm>path engine</firstterm>
-   for evaluation. If the expression matches the queried JSON data,
-   the corresponding JSON item, or set of items, is returned.
-   If there is no match, the result will be <literal>NULL</literal>,
-   <literal>false</literal>, or an error, depending on the function.
-   Path expressions are written in the SQL/JSON path language
-   and can include arithmetic expressions and functions.
-  </para>
-
-  <para>
-   A path expression consists of a sequence of elements allowed
-   by the <type>jsonpath</type> data type.
-   The path expression is normally evaluated from left to right, but
-   you can use parentheses to change the order of operations.
-   If the evaluation is successful, a sequence of JSON items is produced,
-   and the evaluation result is returned to the JSON query function
-   that completes the specified computation.
-  </para>
-
-  <para>
-   To refer to the JSON value being queried (the
-   <firstterm>context item</firstterm>), use the <literal>$</literal> variable
-   in the path expression. The first element of a path must always
-   be <literal>$</literal>. It can be followed by one or more
-   <link linkend="type-jsonpath-accessors">accessor operators</link>,
-   which go down the JSON structure level by level to retrieve sub-items
-   of the context item. Each accessor operator acts on the
-   result(s) of the previous evaluation step, producing zero, one, or more
-   output items from each input item.
-  </para>
-
-  <para>
-   For example, suppose you have some JSON data from a GPS tracker that you
-   would like to parse, such as:
-<programlisting>
-SELECT '{
-  "track": {
-    "segments": [
-      {
-        "location":   [ 47.763, 13.4034 ],
-        "start time": "2018-10-14 10:05:14",
-        "HR": 73
-      },
-      {
-        "location":   [ 47.706, 13.2635 ],
-        "start time": "2018-10-14 10:39:21",
-        "HR": 135
-      }
-    ]
-  }
-}' AS json \gset
-</programlisting>
-   (The above example can be copied-and-pasted
-   into <application>psql</application> to set things up for the following
-   examples.  Then <application>psql</application> will
-   expand <literal>:'json'</literal> into a suitably-quoted string
-   constant containing the JSON value.)
-  </para>
-
-  <para>
-   To retrieve the available track segments, you need to use the
-   <literal>.<replaceable>key</replaceable></literal> accessor
-   operator to descend through surrounding JSON objects, for example:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments');</userinput>
-                                                                         jsonb_path_query
------------------------------------------------------------&zwsp;-----------------------------------------------------------&zwsp;---------------------------------------------
- [{"HR": 73, "location": [47.763, 13.4034], "start time": "2018-10-14 10:05:14"}, {"HR": 135, "location": [47.706, 13.2635], "start time": "2018-10-14 10:39:21"}]
-</screen>
-  </para>
-
-  <para>
-   To retrieve the contents of an array, you typically use the
-   <literal>[*]</literal> operator.
-   The following example will return the location coordinates for all
-   the available track segments:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments[*].location');</userinput>
- jsonb_path_query
--------------------
- [47.763, 13.4034]
- [47.706, 13.2635]
-</screen>
-   Here we started with the whole JSON input value (<literal>$</literal>),
-   then the <literal>.track</literal> accessor selected the JSON object
-   associated with the <literal>"track"</literal> object key, then
-   the <literal>.segments</literal> accessor selected the JSON array
-   associated with the <literal>"segments"</literal> key within that
-   object, then the <literal>[*]</literal> accessor selected each element
-   of that array (producing a series of items), then
-   the <literal>.location</literal> accessor selected the JSON array
-   associated with the <literal>"location"</literal> key within each of
-   those objects.  In this example, each of those objects had
-   a <literal>"location"</literal> key; but if any of them did not,
-   the <literal>.location</literal> accessor would have simply produced no
-   output for that input item.
-  </para>
-
-  <para>
-   To return the coordinates of the first segment only, you can
-   specify the corresponding subscript in the <literal>[]</literal>
-   accessor operator. Recall that JSON array indexes are 0-relative:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments[0].location');</userinput>
- jsonb_path_query
--------------------
- [47.763, 13.4034]
-</screen>
-  </para>
-
-  <para>
-   The result of each path evaluation step can be processed
-   by one or more of the <type>jsonpath</type> operators and methods
-   listed in <xref linkend="functions-sqljson-path-operators"/>.
-   Each method name must be preceded by a dot. For example,
-   you can get the size of an array:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments.size()');</userinput>
- jsonb_path_query
-------------------
- 2
-</screen>
-   More examples of using <type>jsonpath</type> operators
-   and methods within path expressions appear below in
-   <xref linkend="functions-sqljson-path-operators"/>.
-  </para>
-
-  <para>
-   A path can also contain
-   <firstterm>filter expressions</firstterm> that work similarly to the
-   <literal>WHERE</literal> clause in SQL. A filter expression begins with
-   a question mark and provides a condition in parentheses:
-
-<synopsis>
-? (<replaceable>condition</replaceable>)
-</synopsis>
-  </para>
-
-  <para>
-   Filter expressions must be written just after the path evaluation step
-   to which they should apply. The result of that step is filtered to include
-   only those items that satisfy the provided condition. SQL/JSON defines
-   three-valued logic, so the condition can
-   produce <literal>true</literal>, <literal>false</literal>,
-   or <literal>unknown</literal>. The <literal>unknown</literal> value
-   plays the same role as SQL <literal>NULL</literal> and can be tested
-   for with the <literal>is unknown</literal> predicate. Further path
-   evaluation steps use only those items for which the filter expression
-   returned <literal>true</literal>.
-  </para>
-
-  <para>
-   The functions and operators that can be used in filter expressions are
-   listed in <xref linkend="functions-sqljson-filter-ex-table"/>.  Within a
-   filter expression, the <literal>@</literal> variable denotes the value
-   being considered (i.e., one result of the preceding path step).  You can
-   write accessor operators after <literal>@</literal> to retrieve component
-   items.
-  </para>
-
-  <para>
-   For example, suppose you would like to retrieve all heart rate values higher
-   than 130. You can achieve this as follows:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments[*].HR ? (@ &gt; 130)');</userinput>
- jsonb_path_query
-------------------
- 135
-</screen>
-  </para>
-
-  <para>
-   To get the start times of segments with such values, you have to
-   filter out irrelevant segments before selecting the start times, so the
-   filter expression is applied to the previous step, and the path used
-   in the condition is different:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments[*] ? (@.HR &gt; 130)."start time"');</userinput>
-   jsonb_path_query
------------------------
- "2018-10-14 10:39:21"
-</screen>
-  </para>
-
-  <para>
-   You can use several filter expressions in sequence, if required.
-   The following example selects start times of all segments that
-   contain locations with relevant coordinates and high heart rate values:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments[*] ? (@.location[1] &lt; 13.4) ? (@.HR &gt; 130)."start time"');</userinput>
-   jsonb_path_query
------------------------
- "2018-10-14 10:39:21"
-</screen>
-  </para>
-
-  <para>
-   Using filter expressions at different nesting levels is also allowed.
-   The following example first filters all segments by location, and then
-   returns high heart rate values for these segments, if available:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments[*] ? (@.location[1] &lt; 13.4).HR ? (@ &gt; 130)');</userinput>
- jsonb_path_query
-------------------
- 135
-</screen>
-  </para>
-
-  <para>
-   You can also nest filter expressions within each other.
-   This example returns the size of the track if it contains any
-   segments with high heart rate values, or an empty sequence otherwise:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track ? (exists(@.segments[*] ? (@.HR &gt; 130))).segments.size()');</userinput>
- jsonb_path_query
-------------------
- 2
-</screen>
-  </para>
-
-  <sect3 id="functions-sqljson-deviations">
-  <title>Deviations from the SQL Standard</title>
-   <para>
-    <productname>PostgreSQL</productname>'s implementation of the SQL/JSON path
-    language has the following deviations from the SQL/JSON standard.
-   </para>
-
-   <sect4 id="functions-sqljson-check-expressions">
-   <title>Boolean Predicate Check Expressions</title>
-    <para>
-     As an extension to the SQL standard,
-     a <productname>PostgreSQL</productname> path expression can be a
-     Boolean predicate, whereas the SQL standard allows predicates only within
-     filters. While SQL-standard path expressions return the relevant
-     element(s) of the queried JSON value, predicate check expressions
-     return the single three-valued <type>jsonb</type> result of the
-     predicate: <literal>true</literal>,
-     <literal>false</literal>, or <literal>null</literal>.
-     For example, we could write this SQL-standard filter expression:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments ?(@[*].HR &gt; 130)');</userinput>
-                                jsonb_path_query
------------------------------------------------------------&zwsp;----------------------
- {"HR": 135, "location": [47.706, 13.2635], "start time": "2018-10-14 10:39:21"}
-</screen>
-     The similar predicate check expression simply
-     returns <literal>true</literal>, indicating that a match exists:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments[*].HR &gt; 130');</userinput>
- jsonb_path_query
-------------------
- true
-</screen>
-     </para>
-
-     <note>
-      <para>
-       Predicate check expressions are required in the
-       <literal>@@</literal> operator (and the
-       <function>jsonb_path_match</function> function), and should not be used
-       with the <literal>@?</literal> operator (or the
-       <function>jsonb_path_exists</function> function).
-      </para>
-     </note>
-    </sect4>
-
-    <sect4 id="functions-sqljson-regular-expression-deviation">
-    <title>Regular Expression Interpretation</title>
-     <para>
-      There are minor differences in the interpretation of regular
-      expression patterns used in <literal>like_regex</literal> filters, as
-      described in <xref linkend="jsonpath-regular-expressions"/>.
-     </para>
-    </sect4>
-   </sect3>
-
-   <sect3 id="functions-sqljson-strict-and-lax-modes">
-   <title>Strict and Lax Modes</title>
-    <para>
-     When you query JSON data, the path expression may not match the
-     actual JSON data structure. An attempt to access a non-existent
-     member of an object or element of an array is defined as a
-     structural error. SQL/JSON path expressions have two modes
-     of handling structural errors:
-    </para>
-
-   <itemizedlist>
-    <listitem>
-     <para>
-      lax (default) &mdash; the path engine implicitly adapts
-      the queried data to the specified path.
-      Any structural errors that cannot be fixed as described below
-      are suppressed, producing no match.
-     </para>
-    </listitem>
-    <listitem>
-     <para>
-      strict &mdash; if a structural error occurs, an error is raised.
-     </para>
-    </listitem>
-   </itemizedlist>
-
-   <para>
-    Lax mode facilitates matching of a JSON document and path
-    expression when the JSON data does not conform to the expected schema.
-    If an operand does not match the requirements of a particular operation,
-    it can be automatically wrapped as an SQL/JSON array, or unwrapped by
-    converting its elements into an SQL/JSON sequence before performing
-    the operation. Also, comparison operators automatically unwrap their
-    operands in lax mode, so you can compare SQL/JSON arrays
-    out-of-the-box. An array of size 1 is considered equal to its sole element.
-    Automatic unwrapping is not performed when:
-    <itemizedlist>
-     <listitem>
-      <para>
-       The path expression contains <literal>type()</literal> or
-       <literal>size()</literal> methods that return the type
-       and the number of elements in the array, respectively.
-      </para>
-     </listitem>
-     <listitem>
-      <para>
-       The queried JSON data contain nested arrays. In this case, only
-       the outermost array is unwrapped, while all the inner arrays
-       remain unchanged. Thus, implicit unwrapping can only go one
-       level down within each path evaluation step.
-      </para>
-     </listitem>
-    </itemizedlist>
-   </para>
-
-   <para>
-    For example, when querying the GPS data listed above, you can
-    abstract from the fact that it stores an array of segments
-    when using lax mode:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', 'lax $.track.segments.location');</userinput>
- jsonb_path_query
--------------------
- [47.763, 13.4034]
- [47.706, 13.2635]
-</screen>
-   </para>
-
-   <para>
-    In strict mode, the specified path must exactly match the structure of
-    the queried JSON document, so using this path
-    expression will cause an error:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', 'strict $.track.segments.location');</userinput>
-ERROR:  jsonpath member accessor can only be applied to an object
-</screen>
-    To get the same result as in lax mode, you have to explicitly unwrap the
-    <literal>segments</literal> array:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', 'strict $.track.segments[*].location');</userinput>
- jsonb_path_query
--------------------
- [47.763, 13.4034]
- [47.706, 13.2635]
-</screen>
-   </para>
-
-   <para>
-    The unwrapping behavior of lax mode can lead to surprising results. For
-    instance, the following query using the <literal>.**</literal> accessor
-    selects every <literal>HR</literal> value twice:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', 'lax $.**.HR');</userinput>
- jsonb_path_query
-------------------
- 73
- 135
- 73
- 135
-</screen>
-    This happens because the <literal>.**</literal> accessor selects both
-    the <literal>segments</literal> array and each of its elements, while
-    the <literal>.HR</literal> accessor automatically unwraps arrays when
-    using lax mode. To avoid surprising results, we recommend using
-    the <literal>.**</literal> accessor only in strict mode. The
-    following query selects each <literal>HR</literal> value just once:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', 'strict $.**.HR');</userinput>
- jsonb_path_query
-------------------
- 73
- 135
-</screen>
-   </para>
-
-   <para>
-    The unwrapping of arrays can also lead to unexpected results. Consider this
-    example, which selects all the <literal>location</literal> arrays:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', 'lax $.track.segments[*].location');</userinput>
- jsonb_path_query
--------------------
- [47.763, 13.4034]
- [47.706, 13.2635]
-(2 rows)
-</screen>
-    As expected it returns the full arrays. But applying a filter expression
-    causes the arrays to be unwrapped to evaluate each item, returning only the
-    items that match the expression:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', 'lax $.track.segments[*].location ?(@[*] &gt; 15)');</userinput>
- jsonb_path_query
-------------------
- 47.763
- 47.706
-(2 rows)
-</screen>
-    This despite the fact that the full arrays are selected by the path
-    expression. Use strict mode to restore selecting the arrays:
-<screen>
-<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', 'strict $.track.segments[*].location ?(@[*] &gt; 15)');</userinput>
- jsonb_path_query
--------------------
- [47.763, 13.4034]
- [47.706, 13.2635]
-(2 rows)
-</screen>
-   </para>
-   </sect3>
-
-   <sect3 id="functions-sqljson-path-operators">
-   <title>SQL/JSON Path Operators and Methods</title>
-
-   <para>
-    <xref linkend="functions-sqljson-op-table"/> shows the operators and
-    methods available in <type>jsonpath</type>.  Note that while the unary
-    operators and methods can be applied to multiple values resulting from a
-    preceding path step, the binary operators (addition etc.) can only be
-    applied to single values.  In lax mode, methods applied to an array will be
-    executed for each value in the array.  The exceptions are
-    <literal>.type()</literal> and <literal>.size()</literal>, which apply to
-    the array itself.
-   </para>
-
-   <table id="functions-sqljson-op-table">
-    <title><type>jsonpath</type> Operators and Methods</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Operator/Method
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>number</replaceable> <literal>+</literal> <replaceable>number</replaceable>
-        <returnvalue><replaceable>number</replaceable></returnvalue>
-       </para>
-       <para>
-        Addition
-       </para>
-       <para>
-        <literal>jsonb_path_query('[2]', '$[0] + 3')</literal>
-        <returnvalue>5</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>+</literal> <replaceable>number</replaceable>
-        <returnvalue><replaceable>number</replaceable></returnvalue>
-       </para>
-       <para>
-        Unary plus (no operation); unlike addition, this can iterate over
-        multiple values
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('{"x": [2,3,4]}', '+ $.x')</literal>
-        <returnvalue>[2, 3, 4]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>number</replaceable> <literal>-</literal> <replaceable>number</replaceable>
-        <returnvalue><replaceable>number</replaceable></returnvalue>
-       </para>
-       <para>
-        Subtraction
-       </para>
-       <para>
-        <literal>jsonb_path_query('[2]', '7 - $[0]')</literal>
-        <returnvalue>5</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>-</literal> <replaceable>number</replaceable>
-        <returnvalue><replaceable>number</replaceable></returnvalue>
-       </para>
-       <para>
-        Negation; unlike subtraction, this can iterate over
-        multiple values
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('{"x": [2,3,4]}', '- $.x')</literal>
-        <returnvalue>[-2, -3, -4]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>number</replaceable> <literal>*</literal> <replaceable>number</replaceable>
-        <returnvalue><replaceable>number</replaceable></returnvalue>
-       </para>
-       <para>
-        Multiplication
-       </para>
-       <para>
-        <literal>jsonb_path_query('[4]', '2 * $[0]')</literal>
-        <returnvalue>8</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>number</replaceable> <literal>/</literal> <replaceable>number</replaceable>
-        <returnvalue><replaceable>number</replaceable></returnvalue>
-       </para>
-       <para>
-        Division
-       </para>
-       <para>
-        <literal>jsonb_path_query('[8.5]', '$[0] / 2')</literal>
-        <returnvalue>4.2500000000000000</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>number</replaceable> <literal>%</literal> <replaceable>number</replaceable>
-        <returnvalue><replaceable>number</replaceable></returnvalue>
-       </para>
-       <para>
-        Modulo (remainder)
-       </para>
-       <para>
-        <literal>jsonb_path_query('[32]', '$[0] % 10')</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>value</replaceable> <literal>.</literal> <literal>type()</literal>
-        <returnvalue><replaceable>string</replaceable></returnvalue>
-       </para>
-       <para>
-        Type of the JSON item (see <function>json_typeof</function>)
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('[1, "2", {}]', '$[*].type()')</literal>
-        <returnvalue>["number", "string", "object"]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>value</replaceable> <literal>.</literal> <literal>size()</literal>
-        <returnvalue><replaceable>number</replaceable></returnvalue>
-       </para>
-       <para>
-        Size of the JSON item (number of array elements, or 1 if not an
-        array)
-       </para>
-       <para>
-        <literal>jsonb_path_query('{"m": [11, 15]}', '$.m.size()')</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>value</replaceable> <literal>.</literal> <literal>boolean()</literal>
-        <returnvalue><replaceable>boolean</replaceable></returnvalue>
-       </para>
-       <para>
-        Boolean value converted from a JSON boolean, number, or string
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('[1, "yes", false]', '$[*].boolean()')</literal>
-        <returnvalue>[true, true, false]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>value</replaceable> <literal>.</literal> <literal>string()</literal>
-        <returnvalue><replaceable>string</replaceable></returnvalue>
-       </para>
-       <para>
-        String value converted from a JSON boolean, number, string, or
-        datetime
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('[1.23, "xyz", false]', '$[*].string()')</literal>
-        <returnvalue>["1.23", "xyz", "false"]</returnvalue>
-       </para>
-       <para>
-        <literal>jsonb_path_query('"2023-08-15 12:34:56"', '$.timestamp().string()')</literal>
-        <returnvalue>"2023-08-15T12:34:56"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>value</replaceable> <literal>.</literal> <literal>double()</literal>
-        <returnvalue><replaceable>number</replaceable></returnvalue>
-       </para>
-       <para>
-        Approximate floating-point number converted from a JSON number or
-        string
-       </para>
-       <para>
-        <literal>jsonb_path_query('{"len": "1.9"}', '$.len.double() * 2')</literal>
-        <returnvalue>3.8</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>number</replaceable> <literal>.</literal> <literal>ceiling()</literal>
-        <returnvalue><replaceable>number</replaceable></returnvalue>
-       </para>
-       <para>
-        Nearest integer greater than or equal to the given number
-       </para>
-       <para>
-        <literal>jsonb_path_query('{"h": 1.3}', '$.h.ceiling()')</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>number</replaceable> <literal>.</literal> <literal>floor()</literal>
-        <returnvalue><replaceable>number</replaceable></returnvalue>
-       </para>
-       <para>
-        Nearest integer less than or equal to the given number
-       </para>
-       <para>
-        <literal>jsonb_path_query('{"h": 1.7}', '$.h.floor()')</literal>
-        <returnvalue>1</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>number</replaceable> <literal>.</literal> <literal>abs()</literal>
-        <returnvalue><replaceable>number</replaceable></returnvalue>
-       </para>
-       <para>
-        Absolute value of the given number
-       </para>
-       <para>
-        <literal>jsonb_path_query('{"z": -0.3}', '$.z.abs()')</literal>
-        <returnvalue>0.3</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>value</replaceable> <literal>.</literal> <literal>bigint()</literal>
-        <returnvalue><replaceable>bigint</replaceable></returnvalue>
-       </para>
-       <para>
-        Big integer value converted from a JSON number or string
-       </para>
-       <para>
-        <literal>jsonb_path_query('{"len": "9876543219"}', '$.len.bigint()')</literal>
-        <returnvalue>9876543219</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>value</replaceable> <literal>.</literal> <literal>decimal( [ <replaceable>precision</replaceable> [ , <replaceable>scale</replaceable> ] ] )</literal>
-        <returnvalue><replaceable>decimal</replaceable></returnvalue>
-       </para>
-       <para>
-        Rounded decimal value converted from a JSON number or string
-        (<literal>precision</literal> and <literal>scale</literal> must be
-        integer values)
-       </para>
-       <para>
-        <literal>jsonb_path_query('1234.5678', '$.decimal(6, 2)')</literal>
-        <returnvalue>1234.57</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>value</replaceable> <literal>.</literal> <literal>integer()</literal>
-        <returnvalue><replaceable>integer</replaceable></returnvalue>
-       </para>
-       <para>
-        Integer value converted from a JSON number or string
-       </para>
-       <para>
-        <literal>jsonb_path_query('{"len": "12345"}', '$.len.integer()')</literal>
-        <returnvalue>12345</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>value</replaceable> <literal>.</literal> <literal>number()</literal>
-        <returnvalue><replaceable>numeric</replaceable></returnvalue>
-       </para>
-       <para>
-        Numeric value converted from a JSON number or string
-       </para>
-       <para>
-        <literal>jsonb_path_query('{"len": "123.45"}', '$.len.number()')</literal>
-        <returnvalue>123.45</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>string</replaceable> <literal>.</literal> <literal>datetime()</literal>
-        <returnvalue><replaceable>datetime_type</replaceable></returnvalue>
-        (see note)
-       </para>
-       <para>
-        Date/time value converted from a string
-       </para>
-       <para>
-        <literal>jsonb_path_query('["2015-8-1", "2015-08-12"]', '$[*] ? (@.datetime() &lt; "2015-08-2".datetime())')</literal>
-        <returnvalue>"2015-8-1"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>string</replaceable> <literal>.</literal> <literal>datetime(<replaceable>template</replaceable>)</literal>
-        <returnvalue><replaceable>datetime_type</replaceable></returnvalue>
-        (see note)
-       </para>
-       <para>
-        Date/time value converted from a string using the
-        specified <function>to_timestamp</function> template
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('["12:30", "18:40"]', '$[*].datetime("HH24:MI")')</literal>
-        <returnvalue>["12:30:00", "18:40:00"]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>string</replaceable> <literal>.</literal> <literal>date()</literal>
-        <returnvalue><replaceable>date</replaceable></returnvalue>
-       </para>
-       <para>
-        Date value converted from a string
-       </para>
-       <para>
-        <literal>jsonb_path_query('"2023-08-15"', '$.date()')</literal>
-        <returnvalue>"2023-08-15"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>string</replaceable> <literal>.</literal> <literal>time()</literal>
-        <returnvalue><replaceable>time without time zone</replaceable></returnvalue>
-       </para>
-       <para>
-        Time without time zone value converted from a string
-       </para>
-       <para>
-        <literal>jsonb_path_query('"12:34:56"', '$.time()')</literal>
-        <returnvalue>"12:34:56"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>string</replaceable> <literal>.</literal> <literal>time(<replaceable>precision</replaceable>)</literal>
-        <returnvalue><replaceable>time without time zone</replaceable></returnvalue>
-       </para>
-       <para>
-        Time without time zone value converted from a string, with fractional
-        seconds adjusted to the given precision
-       </para>
-       <para>
-        <literal>jsonb_path_query('"12:34:56.789"', '$.time(2)')</literal>
-        <returnvalue>"12:34:56.79"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>string</replaceable> <literal>.</literal> <literal>time_tz()</literal>
-        <returnvalue><replaceable>time with time zone</replaceable></returnvalue>
-       </para>
-       <para>
-        Time with time zone value converted from a string
-       </para>
-       <para>
-        <literal>jsonb_path_query('"12:34:56 +05:30"', '$.time_tz()')</literal>
-        <returnvalue>"12:34:56+05:30"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>string</replaceable> <literal>.</literal> <literal>time_tz(<replaceable>precision</replaceable>)</literal>
-        <returnvalue><replaceable>time with time zone</replaceable></returnvalue>
-       </para>
-       <para>
-        Time with time zone value converted from a string, with fractional
-        seconds adjusted to the given precision
-       </para>
-       <para>
-        <literal>jsonb_path_query('"12:34:56.789 +05:30"', '$.time_tz(2)')</literal>
-        <returnvalue>"12:34:56.79+05:30"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>string</replaceable> <literal>.</literal> <literal>timestamp()</literal>
-        <returnvalue><replaceable>timestamp without time zone</replaceable></returnvalue>
-       </para>
-       <para>
-        Timestamp without time zone value converted from a string
-       </para>
-       <para>
-        <literal>jsonb_path_query('"2023-08-15 12:34:56"', '$.timestamp()')</literal>
-        <returnvalue>"2023-08-15T12:34:56"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>string</replaceable> <literal>.</literal> <literal>timestamp(<replaceable>precision</replaceable>)</literal>
-        <returnvalue><replaceable>timestamp without time zone</replaceable></returnvalue>
-       </para>
-       <para>
-        Timestamp without time zone value converted from a string, with
-        fractional seconds adjusted to the given precision
-       </para>
-       <para>
-        <literal>jsonb_path_query('"2023-08-15 12:34:56.789"', '$.timestamp(2)')</literal>
-        <returnvalue>"2023-08-15T12:34:56.79"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>string</replaceable> <literal>.</literal> <literal>timestamp_tz()</literal>
-        <returnvalue><replaceable>timestamp with time zone</replaceable></returnvalue>
-       </para>
-       <para>
-        Timestamp with time zone value converted from a string
-       </para>
-       <para>
-        <literal>jsonb_path_query('"2023-08-15 12:34:56 +05:30"', '$.timestamp_tz()')</literal>
-        <returnvalue>"2023-08-15T12:34:56+05:30"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>string</replaceable> <literal>.</literal> <literal>timestamp_tz(<replaceable>precision</replaceable>)</literal>
-        <returnvalue><replaceable>timestamp with time zone</replaceable></returnvalue>
-       </para>
-       <para>
-        Timestamp with time zone value converted from a string, with fractional
-        seconds adjusted to the given precision
-       </para>
-       <para>
-        <literal>jsonb_path_query('"2023-08-15 12:34:56.789 +05:30"', '$.timestamp_tz(2)')</literal>
-        <returnvalue>"2023-08-15T12:34:56.79+05:30"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>object</replaceable> <literal>.</literal> <literal>keyvalue()</literal>
-        <returnvalue><replaceable>array</replaceable></returnvalue>
-       </para>
-       <para>
-        The object's key-value pairs, represented as an array of objects
-        containing three fields: <literal>"key"</literal>,
-        <literal>"value"</literal>, and <literal>"id"</literal>;
-        <literal>"id"</literal> is a unique identifier of the object the
-        key-value pair belongs to
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('{"x": "20", "y": 32}', '$.keyvalue()')</literal>
-        <returnvalue>[{"id": 0, "key": "x", "value": "20"}, {"id": 0, "key": "y", "value": 32}]</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-    <note>
-     <para>
-      The result type of the <literal>datetime()</literal> and
-      <literal>datetime(<replaceable>template</replaceable>)</literal>
-      methods can be <type>date</type>, <type>timetz</type>, <type>time</type>,
-      <type>timestamptz</type>, or <type>timestamp</type>.
-      Both methods determine their result type dynamically.
-     </para>
-     <para>
-      The <literal>datetime()</literal> method sequentially tries to
-      match its input string to the ISO formats
-      for <type>date</type>, <type>timetz</type>, <type>time</type>,
-      <type>timestamptz</type>, and <type>timestamp</type>. It stops on
-      the first matching format and emits the corresponding data type.
-     </para>
-     <para>
-      The <literal>datetime(<replaceable>template</replaceable>)</literal>
-      method determines the result type according to the fields used in the
-      provided template string.
-     </para>
-     <para>
-      The <literal>datetime()</literal> and
-      <literal>datetime(<replaceable>template</replaceable>)</literal> methods
-      use the same parsing rules as the <literal>to_timestamp</literal> SQL
-      function does (see <xref linkend="functions-formatting"/>), with three
-      exceptions.  First, these methods don't allow unmatched template
-      patterns.  Second, only the following separators are allowed in the
-      template string: minus sign, period, solidus (slash), comma, apostrophe,
-      semicolon, colon and space.  Third, separators in the template string
-      must exactly match the input string.
-     </para>
-     <para>
-      If different date/time types need to be compared, an implicit cast is
-      applied. A <type>date</type> value can be cast to <type>timestamp</type>
-      or <type>timestamptz</type>, <type>timestamp</type> can be cast to
-      <type>timestamptz</type>, and <type>time</type> to <type>timetz</type>.
-      However, all but the first of these conversions depend on the current
-      <xref linkend="guc-timezone"/> setting, and thus can only be performed
-      within timezone-aware <type>jsonpath</type> functions.  Similarly, other
-      date/time-related methods that convert strings to date/time types
-      also do this casting, which may involve the current
-      <xref linkend="guc-timezone"/> setting. Therefore, these conversions can
-      also only be performed within timezone-aware <type>jsonpath</type>
-      functions.
-     </para>
-    </note>
-
-   <para>
-    <xref linkend="functions-sqljson-filter-ex-table"/> shows the available
-    filter expression elements.
-   </para>
-
-   <table id="functions-sqljson-filter-ex-table">
-    <title><type>jsonpath</type> Filter Expression Elements</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Predicate/Value
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>value</replaceable> <literal>==</literal> <replaceable>value</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Equality comparison (this, and the other comparison operators, work on
-        all JSON scalar values)
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('[1, "a", 1, 3]', '$[*] ? (@ == 1)')</literal>
-        <returnvalue>[1, 1]</returnvalue>
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('[1, "a", 1, 3]', '$[*] ? (@ == "a")')</literal>
-        <returnvalue>["a"]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>value</replaceable> <literal>!=</literal> <replaceable>value</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para role="func_signature">
-        <replaceable>value</replaceable> <literal>&lt;&gt;</literal> <replaceable>value</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Non-equality comparison
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('[1, 2, 1, 3]', '$[*] ? (@ != 1)')</literal>
-        <returnvalue>[2, 3]</returnvalue>
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('["a", "b", "c"]', '$[*] ? (@ &lt;&gt; "b")')</literal>
-        <returnvalue>["a", "c"]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>value</replaceable> <literal>&lt;</literal> <replaceable>value</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Less-than comparison
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('[1, 2, 3]', '$[*] ? (@ &lt; 2)')</literal>
-        <returnvalue>[1]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>value</replaceable> <literal>&lt;=</literal> <replaceable>value</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Less-than-or-equal-to comparison
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('["a", "b", "c"]', '$[*] ? (@ &lt;= "b")')</literal>
-        <returnvalue>["a", "b"]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>value</replaceable> <literal>&gt;</literal> <replaceable>value</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Greater-than comparison
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('[1, 2, 3]', '$[*] ? (@ &gt; 2)')</literal>
-        <returnvalue>[3]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>value</replaceable> <literal>&gt;=</literal> <replaceable>value</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Greater-than-or-equal-to comparison
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('[1, 2, 3]', '$[*] ? (@ &gt;= 2)')</literal>
-        <returnvalue>[2, 3]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>true</literal>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        JSON constant <literal>true</literal>
-       </para>
-       <para>
-        <literal>jsonb_path_query('[{"name": "John", "parent": false}, {"name": "Chris", "parent": true}]', '$[*] ? (@.parent == true)')</literal>
-        <returnvalue>{"name": "Chris", "parent": true}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>false</literal>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        JSON constant <literal>false</literal>
-       </para>
-       <para>
-        <literal>jsonb_path_query('[{"name": "John", "parent": false}, {"name": "Chris", "parent": true}]', '$[*] ? (@.parent == false)')</literal>
-        <returnvalue>{"name": "John", "parent": false}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>null</literal>
-        <returnvalue><replaceable>value</replaceable></returnvalue>
-       </para>
-       <para>
-        JSON constant <literal>null</literal> (note that, unlike in SQL,
-        comparison to <literal>null</literal> works normally)
-       </para>
-       <para>
-        <literal>jsonb_path_query('[{"name": "Mary", "job": null}, {"name": "Michael", "job": "driver"}]', '$[*] ? (@.job == null) .name')</literal>
-        <returnvalue>"Mary"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>boolean</replaceable> <literal>&amp;&amp;</literal> <replaceable>boolean</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Boolean AND
-       </para>
-       <para>
-        <literal>jsonb_path_query('[1, 3, 7]', '$[*] ? (@ &gt; 1 &amp;&amp; @ &lt; 5)')</literal>
-        <returnvalue>3</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>boolean</replaceable> <literal>||</literal> <replaceable>boolean</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Boolean OR
-       </para>
-       <para>
-        <literal>jsonb_path_query('[1, 3, 7]', '$[*] ? (@ &lt; 1 || @ &gt; 5)')</literal>
-        <returnvalue>7</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>!</literal> <replaceable>boolean</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Boolean NOT
-       </para>
-       <para>
-        <literal>jsonb_path_query('[1, 3, 7]', '$[*] ? (!(@ &lt; 5))')</literal>
-        <returnvalue>7</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>boolean</replaceable> <literal>is unknown</literal>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Tests whether a Boolean condition is <literal>unknown</literal>.
-       </para>
-       <para>
-        <literal>jsonb_path_query('[-1, 2, 7, "foo"]', '$[*] ? ((@ > 0) is unknown)')</literal>
-        <returnvalue>"foo"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>string</replaceable> <literal>like_regex</literal> <replaceable>string</replaceable> <optional> <literal>flag</literal> <replaceable>string</replaceable> </optional>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Tests whether the first operand matches the regular expression
-        given by the second operand, optionally with modifications
-        described by a string of <literal>flag</literal> characters (see
-        <xref linkend="jsonpath-regular-expressions"/>).
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('["abc", "abd", "aBdC", "abdacb", "babc"]', '$[*] ? (@ like_regex "^ab.*c")')</literal>
-        <returnvalue>["abc", "abdacb"]</returnvalue>
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('["abc", "abd", "aBdC", "abdacb", "babc"]', '$[*] ? (@ like_regex "^ab.*c" flag "i")')</literal>
-        <returnvalue>["abc", "aBdC", "abdacb"]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <replaceable>string</replaceable> <literal>starts with</literal> <replaceable>string</replaceable>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Tests whether the second operand is an initial substring of the first
-        operand.
-       </para>
-       <para>
-        <literal>jsonb_path_query('["John Smith", "Mary Stone", "Bob Johnson"]', '$[*] ? (@ starts with "John")')</literal>
-        <returnvalue>"John Smith"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <literal>exists</literal> <literal>(</literal> <replaceable>path_expression</replaceable> <literal>)</literal>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Tests whether a path expression matches at least one SQL/JSON item.
-        Returns <literal>unknown</literal> if the path expression would result
-        in an error; the second example uses this to avoid a no-such-key error
-        in strict mode.
-       </para>
-       <para>
-        <literal>jsonb_path_query('{"x": [1, 2], "y": [2, 4]}', 'strict $.* ? (exists (@ ? (@[*] &gt; 2)))')</literal>
-        <returnvalue>[2, 4]</returnvalue>
-       </para>
-       <para>
-        <literal>jsonb_path_query_array('{"value": 41}', 'strict $ ? (exists (@.name)) .name')</literal>
-        <returnvalue>[]</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   </sect3>
-
-   <sect3 id="jsonpath-regular-expressions">
-    <title>SQL/JSON Regular Expressions</title>
-
-    <indexterm zone="jsonpath-regular-expressions">
-     <primary><literal>LIKE_REGEX</literal></primary>
-     <secondary>in SQL/JSON</secondary>
-    </indexterm>
-
-    <para>
-     SQL/JSON path expressions allow matching text to a regular expression
-     with the <literal>like_regex</literal> filter.  For example, the
-     following SQL/JSON path query would case-insensitively match all
-     strings in an array that start with an English vowel:
-<programlisting>
-$[*] ? (@ like_regex "^[aeiou]" flag "i")
-</programlisting>
-    </para>
-
-    <para>
-     The optional <literal>flag</literal> string may include one or more of
-     the characters
-     <literal>i</literal> for case-insensitive match,
-     <literal>m</literal> to allow <literal>^</literal>
-     and <literal>$</literal> to match at newlines,
-     <literal>s</literal> to allow <literal>.</literal> to match a newline,
-     and <literal>q</literal> to quote the whole pattern (reducing the
-     behavior to a simple substring match).
-    </para>
-
-    <para>
-     The SQL/JSON standard borrows its definition for regular expressions
-     from the <literal>LIKE_REGEX</literal> operator, which in turn uses the
-     XQuery standard.  PostgreSQL does not currently support the
-     <literal>LIKE_REGEX</literal> operator.  Therefore,
-     the <literal>like_regex</literal> filter is implemented using the
-     POSIX regular expression engine described in
-     <xref linkend="functions-posix-regexp"/>.  This leads to various minor
-     discrepancies from standard SQL/JSON behavior, which are cataloged in
-     <xref linkend="posix-vs-xquery"/>.
-     Note, however, that the flag-letter incompatibilities described there
-     do not apply to SQL/JSON, as it translates the XQuery flag letters to
-     match what the POSIX engine expects.
-    </para>
-
-    <para>
-     Keep in mind that the pattern argument of <literal>like_regex</literal>
-     is a JSON path string literal, written according to the rules given in
-     <xref linkend="datatype-jsonpath"/>.  This means in particular that any
-     backslashes you want to use in the regular expression must be doubled.
-     For example, to match string values of the root document that contain
-     only digits:
-<programlisting>
-$.* ? (@ like_regex "^\\d+$")
-</programlisting>
-    </para>
-   </sect3>
-  </sect2>
-
-   <sect2 id="sqljson-query-functions">
-    <title>SQL/JSON Query Functions</title>
-  <para>
-   SQL/JSON functions <literal>JSON_EXISTS()</literal>,
-   <literal>JSON_QUERY()</literal>, and <literal>JSON_VALUE()</literal>
-   described in <xref linkend="functions-sqljson-querying"/> can be used
-   to query JSON documents.  Each of these functions apply a
-   <replaceable>path_expression</replaceable> (an SQL/JSON path query) to a
-   <replaceable>context_item</replaceable> (the document).  See
-   <xref linkend="functions-sqljson-path"/> for more details on what
-   the <replaceable>path_expression</replaceable> can contain. The
-   <replaceable>path_expression</replaceable> can also reference variables,
-   whose values are specified with their respective names in the
-   <literal>PASSING</literal> clause that is supported by each function.
-   <replaceable>context_item</replaceable> can be a <type>jsonb</type> value
-   or a character string that can be successfully cast to <type>jsonb</type>.
-  </para>
-
-  <table id="functions-sqljson-querying">
-   <title>SQL/JSON Query Functions</title>
-   <tgroup cols="1">
-    <thead>
-     <row>
-      <entry role="func_table_entry"><para role="func_signature">
-        Function signature
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-      </para></entry>
-     </row>
-    </thead>
-    <tbody>
-     <row>
-      <entry role="func_table_entry"><para role="func_signature">
-        <indexterm><primary>json_exists</primary></indexterm>
-<synopsis>
-<function>JSON_EXISTS</function> (
-<replaceable>context_item</replaceable>, <replaceable>path_expression</replaceable>
-<optional> <literal>PASSING</literal> { <replaceable>value</replaceable> <literal>AS</literal> <replaceable>varname</replaceable> } <optional>, ...</optional></optional>
-<optional>{ <literal>TRUE</literal> | <literal>FALSE</literal> |<literal> UNKNOWN</literal> | <literal>ERROR</literal> } <literal>ON ERROR</literal> </optional>) <returnvalue>boolean</returnvalue>
-</synopsis>
-       </para>
-     <itemizedlist>
-      <listitem>
-       <para>
-        Returns true if the SQL/JSON <replaceable>path_expression</replaceable>
-        applied to the <replaceable>context_item</replaceable> yields any
-        items, false otherwise.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        The <literal>ON ERROR</literal> clause specifies the behavior if
-        an error occurs during <replaceable>path_expression</replaceable>
-        evaluation.  Specifying <literal>ERROR</literal> will cause an error to
-        be thrown with the appropriate message.  Other options include
-        returning <type>boolean</type> values <literal>FALSE</literal> or
-        <literal>TRUE</literal> or the value <literal>UNKNOWN</literal> which
-        is actually an SQL NULL. The default when no <literal>ON ERROR</literal>
-        clause is specified is to return the <type>boolean</type> value
-        <literal>FALSE</literal>.
-       </para>
-      </listitem>
-      </itemizedlist>
-       <para>
-        Examples:
-       </para>
-       <para>
-        <literal>JSON_EXISTS(jsonb '{"key1": [1,2,3]}', 'strict $.key1[*] ? (@ > $x)' PASSING 2 AS x)</literal>
-        <returnvalue>t</returnvalue>
-       </para>
-       <para>
-        <literal>JSON_EXISTS(jsonb '{"a": [1,2,3]}', 'lax $.a[5]' ERROR ON ERROR)</literal>
-        <returnvalue>f</returnvalue>
-       </para>
-       <para>
-        <literal>JSON_EXISTS(jsonb '{"a": [1,2,3]}', 'strict $.a[5]' ERROR ON ERROR)</literal>
-        <returnvalue></returnvalue>
-<programlisting>
-ERROR:  jsonpath array subscript is out of bounds
-</programlisting>
-      </para></entry>
-     </row>
-     <row>
-      <entry role="func_table_entry"><para role="func_signature">
-        <indexterm><primary>json_query</primary></indexterm>
-<synopsis>
-<function>JSON_QUERY</function> (
-<replaceable>context_item</replaceable>, <replaceable>path_expression</replaceable>
-<optional> <literal>PASSING</literal> { <replaceable>value</replaceable> <literal>AS</literal> <replaceable>varname</replaceable> } <optional>, ...</optional></optional>
-<optional> <literal>RETURNING</literal> <replaceable>data_type</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional> </optional>
-<optional> { <literal>WITHOUT</literal> | <literal>WITH</literal> { <literal>CONDITIONAL</literal> | <optional><literal>UNCONDITIONAL</literal></optional> } } <optional> <literal>ARRAY</literal> </optional> <literal>WRAPPER</literal> </optional>
-<optional> { <literal>KEEP</literal> | <literal>OMIT</literal> } <literal>QUOTES</literal> <optional> <literal>ON SCALAR STRING</literal> </optional> </optional>
-<optional> { <literal>ERROR</literal> | <literal>NULL</literal> | <literal>EMPTY</literal> { <optional> <literal>ARRAY</literal> </optional> | <literal>OBJECT</literal> } | <literal>DEFAULT</literal> <replaceable>expression</replaceable> } <literal>ON EMPTY</literal> </optional>
-<optional> { <literal>ERROR</literal> | <literal>NULL</literal> | <literal>EMPTY</literal> { <optional> <literal>ARRAY</literal> </optional> | <literal>OBJECT</literal> } | <literal>DEFAULT</literal> <replaceable>expression</replaceable> } <literal>ON ERROR</literal> </optional>) <returnvalue>jsonb</returnvalue>
-</synopsis>
-      </para>
-     <itemizedlist>
-      <listitem>
-       <para>
-        Returns the result of applying the SQL/JSON
-        <replaceable>path_expression</replaceable> to the
-        <replaceable>context_item</replaceable>.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-         By default, the result is returned as a value of type <type>jsonb</type>,
-         though the <literal>RETURNING</literal> clause can be used to return
-         as some other type to which it can be successfully coerced.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        If the path expression may return multiple values, it might be necessary
-        to wrap those values using the <literal>WITH WRAPPER</literal> clause to
-        make it a valid JSON string, because the default behavior is to not wrap
-        them, as if <literal>WITHOUT WRAPPER</literal> were specified. The
-        <literal>WITH WRAPPER</literal> clause is by default taken to mean
-        <literal>WITH UNCONDITIONAL WRAPPER</literal>, which means that even a
-        single result value will be wrapped. To apply the wrapper only when
-        multiple values are present, specify <literal>WITH CONDITIONAL WRAPPER</literal>.
-        Getting multiple values in result will be treated as an error if
-        <literal>WITHOUT WRAPPER</literal> is specified.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        If the result is a scalar string, by default, the returned value will
-        be surrounded by quotes, making it a valid JSON value.  It can be made
-        explicit by specifying <literal>KEEP QUOTES</literal>.  Conversely,
-        quotes can be omitted by specifying <literal>OMIT QUOTES</literal>.
-        To ensure that the result is a valid JSON value, <literal>OMIT QUOTES</literal>
-        cannot be specified when <literal>WITH WRAPPER</literal> is also
-        specified.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        The <literal>ON EMPTY</literal> clause specifies the behavior if
-        evaluating <replaceable>path_expression</replaceable> yields an empty
-        set. The <literal>ON ERROR</literal> clause specifies the behavior
-        if an error occurs when evaluating <replaceable>path_expression</replaceable>,
-        when coercing the result value to the <literal>RETURNING</literal> type,
-        or when evaluating the <literal>ON EMPTY</literal> expression if the
-        <replaceable>path_expression</replaceable> evaluation returns an empty
-        set.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        For both <literal>ON EMPTY</literal> and <literal>ON ERROR</literal>,
-        specifying <literal>ERROR</literal> will cause an error to be thrown with
-        the appropriate message. Other options include returning an SQL NULL, an
-        empty array (<literal>EMPTY <optional>ARRAY</optional></literal>),
-        an empty object (<literal>EMPTY OBJECT</literal>), or a user-specified
-        expression (<literal>DEFAULT</literal> <replaceable>expression</replaceable>)
-        that can be coerced to jsonb or the type specified in <literal>RETURNING</literal>.
-        The default when <literal>ON EMPTY</literal> or <literal>ON ERROR</literal>
-        is not specified is to return an SQL NULL value.
-       </para>
-      </listitem>
-     </itemizedlist>
-       <para>
-        Examples:
-       </para>
-       <para>
-        <literal>JSON_QUERY(jsonb '[1,[2,3],null]', 'lax $[*][$off]' PASSING 1 AS off WITH CONDITIONAL WRAPPER)</literal>
-        <returnvalue>3</returnvalue>
-       </para>
-       <para>
-        <literal>JSON_QUERY(jsonb '{"a": "[1, 2]"}', 'lax $.a' OMIT QUOTES)</literal>
-        <returnvalue>[1, 2]</returnvalue>
-       </para>
-       <para>
-        <literal>JSON_QUERY(jsonb '{"a": "[1, 2]"}', 'lax $.a' RETURNING int[] OMIT QUOTES ERROR ON ERROR)</literal>
-        <returnvalue></returnvalue>
-<programlisting>
-ERROR:  malformed array literal: "[1, 2]"
-DETAIL:  Missing "]" after array dimensions.
-</programlisting>
-       </para>
-      </entry>
-     </row>
-     <row>
-      <entry role="func_table_entry"><para role="func_signature">
-        <indexterm><primary>json_value</primary></indexterm>
-<synopsis>
-<function>JSON_VALUE</function> (
-<replaceable>context_item</replaceable>, <replaceable>path_expression</replaceable>
-<optional> <literal>PASSING</literal> { <replaceable>value</replaceable> <literal>AS</literal> <replaceable>varname</replaceable> } <optional>, ...</optional></optional>
-<optional> <literal>RETURNING</literal> <replaceable>data_type</replaceable> </optional>
-<optional> { <literal>ERROR</literal> | <literal>NULL</literal> | <literal>DEFAULT</literal> <replaceable>expression</replaceable> } <literal>ON EMPTY</literal> </optional>
-<optional> { <literal>ERROR</literal> | <literal>NULL</literal> | <literal>DEFAULT</literal> <replaceable>expression</replaceable> } <literal>ON ERROR</literal> </optional>) <returnvalue>text</returnvalue>
-</synopsis>
-       </para>
-     <itemizedlist>
-      <listitem>
-       <para>
-        Returns the result of applying the SQL/JSON
-        <replaceable>path_expression</replaceable> to the
-        <replaceable>context_item</replaceable>.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        Only use <function>JSON_VALUE()</function> if the extracted value is
-        expected to be a single <acronym>SQL/JSON</acronym> scalar item;
-        getting multiple values will be treated as an error. If you expect that
-        extracted value might be an object or an array, use the
-        <function>JSON_QUERY</function> function instead.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        By default, the result, which must be a single scalar value, is
-        returned as a value of type <type>text</type>, though the
-        <literal>RETURNING</literal> clause can be used to return as some
-        other type to which it can be successfully coerced.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        The <literal>ON ERROR</literal> and <literal>ON EMPTY</literal>
-        clauses have similar semantics as mentioned in the description of
-        <function>JSON_QUERY</function>, except the set of values returned in
-        lieu of throwing an error is different.
-       </para>
-      </listitem>
-      <listitem>
-       <para>
-        Note that scalar strings returned by <function>JSON_VALUE</function>
-        always have their quotes removed, equivalent to specifying
-        <literal>OMIT QUOTES</literal> in <function>JSON_QUERY</function>.
-       </para>
-      </listitem>
-     </itemizedlist>
-       <para>
-        Examples:
-       </para>
-       <para>
-        <literal>JSON_VALUE(jsonb '"123.45"', '$' RETURNING float)</literal>
-        <returnvalue>123.45</returnvalue>
-       </para>
-       <para>
-        <literal>JSON_VALUE(jsonb '"03:04 2015-02-01"', '$.datetime("HH24:MI&nbsp;YYYY-MM-DD")' RETURNING date)</literal>
-        <returnvalue>2015-02-01</returnvalue>
-       </para>
-       <para>
-        <literal>JSON_VALUE(jsonb '[1,2]', 'strict $[$off]' PASSING 1 as off)</literal>
-        <returnvalue>2</returnvalue>
-       </para>
-       <para>
-        <literal>JSON_VALUE(jsonb '[1,2]', 'strict $[*]' DEFAULT 9 ON ERROR)</literal>
-        <returnvalue>9</returnvalue>
-       </para>
-      </entry>
-     </row>
-    </tbody>
-   </tgroup>
-  </table>
-  <note>
-   <para>
-    The <replaceable>context_item</replaceable> expression is converted to
-    <type>jsonb</type> by an implicit cast if the expression is not already of
-    type <type>jsonb</type>. Note, however, that any parsing errors that occur
-    during that conversion are thrown unconditionally, that is, are not
-    handled according to the (specified or implicit) <literal>ON ERROR</literal>
-    clause.
-   </para>
-  </note>
-  <note>
-   <para>
-    <function>JSON_VALUE()</function> returns an SQL NULL if
-    <replaceable>path_expression</replaceable> returns a JSON
-    <literal>null</literal>, whereas <function>JSON_QUERY()</function> returns
-    the JSON <literal>null</literal> as is.
-   </para>
-  </note>
-  </sect2>
-
- <sect2 id="functions-sqljson-table">
-  <title>JSON_TABLE</title>
-  <indexterm>
-   <primary>json_table</primary>
-  </indexterm>
-
-  <para>
-   <function>JSON_TABLE</function> is an SQL/JSON function which
-   queries <acronym>JSON</acronym> data
-   and presents the results as a relational view, which can be accessed as a
-   regular SQL table. You can use <function>JSON_TABLE</function> inside
-   the <literal>FROM</literal> clause of a <literal>SELECT</literal>,
-   <literal>UPDATE</literal>, or <literal>DELETE</literal> and as data source
-   in a <literal>MERGE</literal> statement.
-  </para>
-
-  <para>
-   Taking JSON data as input, <function>JSON_TABLE</function> uses a JSON path
-   expression to extract a part of the provided data to use as a
-   <firstterm>row pattern</firstterm> for the constructed view.  Each SQL/JSON
-   value given by the row pattern serves as source for a separate row in the
-   constructed view.
-  </para>
-
-  <para>
-   To split the row pattern into columns, <function>JSON_TABLE</function>
-   provides the <literal>COLUMNS</literal> clause that defines the
-   schema of the created view. For each column, a separate JSON path expression
-   can be specified to be evaluated against the row pattern to get an SQL/JSON
-   value that will become the value for the specified column in a given output
-   row.
-  </para>
-
-  <para>
-   JSON data stored at a nested level of the row pattern can be extracted using
-   the <literal>NESTED PATH</literal> clause.  Each
-   <literal>NESTED PATH</literal> clause can be used to generate one or more
-   columns using the data from a nested level of the row pattern.  Those
-   columns can be specified using a <literal>COLUMNS</literal> clause that
-   looks similar to the top-level COLUMNS clause.  Rows constructed from
-   NESTED COLUMNS are called <firstterm>child rows</firstterm> and are joined
-   against the row constructed from the columns specified in the parent
-   <literal>COLUMNS</literal> clause to get the row in the final view.  Child
-   columns themselves may contain a <literal>NESTED PATH</literal>
-   specification thus allowing to extract data located at arbitrary nesting
-   levels.  Columns produced by multiple <literal>NESTED PATH</literal>s at the
-   same level are considered to be <firstterm>siblings</firstterm> of each
-   other and their rows after joining with the parent row are combined using
-   UNION.
-  </para>
-
-  <para>
-   The rows produced by <function>JSON_TABLE</function> are laterally
-   joined to the row that generated them, so you do not have to explicitly join
-   the constructed view with the original table holding <acronym>JSON</acronym>
-   data.
-  </para>
-
-  <para>
-   The syntax is:
-  </para>
-
-<synopsis>
-JSON_TABLE (
-    <replaceable>context_item</replaceable>, <replaceable>path_expression</replaceable> <optional> AS <replaceable>json_path_name</replaceable> </optional> <optional> PASSING { <replaceable>value</replaceable> AS <replaceable>varname</replaceable> } <optional>, ...</optional> </optional>
-    COLUMNS ( <replaceable class="parameter">json_table_column</replaceable> <optional>, ...</optional> )
-    <optional> { <literal>ERROR</literal> | <literal>EMPTY</literal> <optional>ARRAY</optional>} <literal>ON ERROR</literal> </optional>
-)
-
-<phrase>
-where <replaceable class="parameter">json_table_column</replaceable> is:
-</phrase>
-  <replaceable>name</replaceable> FOR ORDINALITY
-  | <replaceable>name</replaceable> <replaceable>type</replaceable>
-        <optional> FORMAT JSON <optional>ENCODING <literal>UTF8</literal></optional></optional>
-        <optional> PATH <replaceable>path_expression</replaceable> </optional>
-        <optional> { WITHOUT | WITH { CONDITIONAL | <optional>UNCONDITIONAL</optional> } } <optional> ARRAY </optional> WRAPPER </optional>
-        <optional> { KEEP | OMIT } QUOTES <optional> ON SCALAR STRING </optional> </optional>
-        <optional> { ERROR | NULL | EMPTY { <optional>ARRAY</optional> | OBJECT } | DEFAULT <replaceable>expression</replaceable> } ON EMPTY </optional>
-        <optional> { ERROR | NULL | EMPTY { <optional>ARRAY</optional> | OBJECT } | DEFAULT <replaceable>expression</replaceable> } ON ERROR </optional>
-  | <replaceable>name</replaceable> <replaceable>type</replaceable> EXISTS <optional> PATH <replaceable>path_expression</replaceable> </optional>
-        <optional> { ERROR | TRUE | FALSE | UNKNOWN } ON ERROR </optional>
-  | NESTED <optional> PATH </optional> <replaceable>path_expression</replaceable> <optional> AS <replaceable>json_path_name</replaceable> </optional> COLUMNS ( <replaceable>json_table_column</replaceable> <optional>, ...</optional> )
-</synopsis>
-
-  <para>
-   Each syntax element is described below in more detail.
-  </para>
-
-  <variablelist>
-   <varlistentry>
-    <term>
-     <literal><replaceable>context_item</replaceable>, <replaceable>path_expression</replaceable> <optional> <literal>AS</literal> <replaceable>json_path_name</replaceable> </optional> <optional> <literal>PASSING</literal> { <replaceable>value</replaceable> <literal>AS</literal> <replaceable>varname</replaceable> } <optional>, ...</optional></optional></literal>
-    </term>
-    <listitem>
-    <para>
-     The <replaceable>context_item</replaceable> specifies the input document
-     to query, the <replaceable>path_expression</replaceable> is an SQL/JSON
-     path expression defining the query, and <replaceable>json_path_name</replaceable>
-     is an optional name for the <replaceable>path_expression</replaceable>.
-     The optional <literal>PASSING</literal> clause provides data values for
-     the variables mentioned in the <replaceable>path_expression</replaceable>.
-     The result of the input data evaluation using the aforementioned elements
-     is called the <firstterm>row pattern</firstterm>, which is used as the
-     source for row values in the constructed view.
-    </para>
-    </listitem>
-   </varlistentry>
-
-   <varlistentry>
-    <term>
-     <literal>COLUMNS</literal> ( <replaceable>json_table_column</replaceable> <optional>, ...</optional> )
-    </term>
-    <listitem>
-
-    <para>
-     The <literal>COLUMNS</literal> clause defining the schema of the
-     constructed view. In this clause, you can specify each column to be
-     filled with an SQL/JSON value obtained by applying a JSON path expression
-     against the row pattern.  <replaceable>json_table_column</replaceable> has
-     the following variants:
-    </para>
-
-  <variablelist>
-   <varlistentry>
-    <term>
-     <replaceable>name</replaceable> <literal>FOR ORDINALITY</literal>
-    </term>
-    <listitem>
-    <para>
-     Adds an ordinality column that provides sequential row numbering starting
-     from 1.  Each <literal>NESTED PATH</literal> (see below) gets its own
-     counter for any nested ordinality columns.
-    </para>
-    </listitem>
-   </varlistentry>
-
-   <varlistentry>
-    <term>
-     <literal><replaceable>name</replaceable> <replaceable>type</replaceable>
-          <optional><literal>FORMAT JSON</literal> <optional>ENCODING <literal>UTF8</literal></optional></optional>
-          <optional> <literal>PATH</literal> <replaceable>path_expression</replaceable> </optional></literal>
-    </term>
-    <listitem>
-    <para>
-     Inserts an SQL/JSON value obtained by applying
-     <replaceable>path_expression</replaceable> against the row pattern into
-     the view's output row after coercing it to specified
-     <replaceable>type</replaceable>.
-    </para>
-    <para>
-     Specifying <literal>FORMAT JSON</literal> makes it explicit that you
-     expect the value to be a valid <type>json</type> object.  It only
-     makes sense to specify <literal>FORMAT JSON</literal> if
-     <replaceable>type</replaceable> is one of <type>bpchar</type>,
-     <type>bytea</type>, <type>character varying</type>, <type>name</type>,
-     <type>json</type>, <type>jsonb</type>, <type>text</type>, or a domain over
-     these types.
-    </para>
-    <para>
-     Optionally, you can specify <literal>WRAPPER</literal> and
-     <literal>QUOTES</literal> clauses to format the output. Note that
-     specifying <literal>OMIT QUOTES</literal> overrides
-     <literal>FORMAT JSON</literal> if also specified, because unquoted
-     literals do not constitute valid <type>json</type> values.
-    </para>
-    <para>
-     Optionally, you can use <literal>ON EMPTY</literal> and
-     <literal>ON ERROR</literal> clauses to specify whether to throw the error
-     or return the specified value when the result of JSON path evaluation is
-     empty and when an error occurs during JSON path evaluation or when
-     coercing the SQL/JSON value to the specified type, respectively.  The
-     default for both is to return a <literal>NULL</literal> value.
-    </para>
-    <note>
-     <para>
-      This clause is internally turned into and has the same semantics as
-      <function>JSON_VALUE</function> or <function>JSON_QUERY</function>.
-      The latter if the specified type is not a scalar type or if either of
-      <literal>FORMAT JSON</literal>, <literal>WRAPPER</literal>, or
-      <literal>QUOTES</literal> clause is present.
-     </para>
-    </note>
-    </listitem>
-   </varlistentry>
-
-   <varlistentry>
-    <term>
-       <replaceable>name</replaceable> <replaceable>type</replaceable>
-       <literal>EXISTS</literal> <optional> <literal>PATH</literal> <replaceable>path_expression</replaceable> </optional>
-    </term>
-    <listitem>
-    <para>
-     Inserts a boolean value obtained by applying
-     <replaceable>path_expression</replaceable> against the row pattern
-     into the view's output row after coercing it to specified
-     <replaceable>type</replaceable>.
-    </para>
-    <para>
-     The value corresponds to whether applying the <literal>PATH</literal>
-     expression to the row pattern yields any values.
-    </para>
-    <para>
-     The specified <replaceable>type</replaceable> should have a cast from the
-     <type>boolean</type> type.
-    </para>
-    <para>
-     Optionally, you can use <literal>ON ERROR</literal> to specify whether to
-     throw the error or return the specified value when an error occurs during
-     JSON path evaluation or when coercing SQL/JSON value to the specified
-     type.  The default is to return a boolean value
-     <literal>FALSE</literal>.
-    </para>
-    <note>
-     <para>
-      This clause is internally turned into and has the same semantics as
-      <function>JSON_EXISTS</function>.
-     </para>
-    </note>
-      </listitem>
-   </varlistentry>
-
-   <varlistentry>
-    <term>
-      <literal>NESTED <optional> PATH </optional></literal> <replaceable>path_expression</replaceable> <optional> <literal>AS</literal> <replaceable>json_path_name</replaceable> </optional>
-          <literal>COLUMNS</literal> ( <replaceable>json_table_column</replaceable> <optional>, ...</optional> )
-    </term>
-    <listitem>
-
-    <para>
-     Extracts SQL/JSON values from nested levels of the row pattern,
-     generates one or more columns as defined by the <literal>COLUMNS</literal>
-     subclause, and inserts the extracted SQL/JSON values into those
-     columns.  The <replaceable>json_table_column</replaceable>
-     expression in the <literal>COLUMNS</literal> subclause uses the same
-     syntax as in the parent <literal>COLUMNS</literal> clause.
-    </para>
-
-    <para>
-     The <literal>NESTED PATH</literal> syntax is recursive,
-     so you can go down multiple nested levels by specifying several
-     <literal>NESTED PATH</literal> subclauses within each other.
-     It allows to unnest the hierarchy of JSON objects and arrays
-     in a single function invocation rather than chaining several
-     <function>JSON_TABLE</function> expressions in an SQL statement.
-    </para>
-    </listitem>
-   </varlistentry>
-  </variablelist>
-
-   <note>
-     <para>
-      In each variant of <replaceable>json_table_column</replaceable> described
-      above, if the <literal>PATH</literal> clause is omitted, path expression
-      <literal>$.<replaceable>name</replaceable></literal> is used, where
-      <replaceable>name</replaceable> is the provided column name.
-     </para>
-    </note>
-
-    </listitem>
-   </varlistentry>
-
-   <varlistentry>
-    <term>
-     <literal>AS</literal> <replaceable>json_path_name</replaceable>
-    </term>
-    <listitem>
-
-    <para>
-     The optional <replaceable>json_path_name</replaceable> serves as an
-     identifier of the provided <replaceable>path_expression</replaceable>.
-     The name must be unique and distinct from the column names.
-    </para>
-    </listitem>
-   </varlistentry>
-
-   <varlistentry>
-    <term>
-     { <literal>ERROR</literal> | <literal>EMPTY</literal> } <literal>ON ERROR</literal>
-    </term>
-    <listitem>
-
-    <para>
-     The optional <literal>ON ERROR</literal> can be used to specify how to
-     handle errors when evaluating the top-level
-     <replaceable>path_expression</replaceable>.  Use <literal>ERROR</literal>
-     if you want the errors to be thrown and <literal>EMPTY</literal> to
-     return an empty table, that is, a table containing 0 rows.  Note that
-     this clause does not affect the errors that occur when evaluating
-     columns, for which the behavior depends on whether the
-     <literal>ON ERROR</literal> clause is specified against a given column.
-    </para>
-    </listitem>
-   </varlistentry>
-  </variablelist>
-
-  <para>Examples</para>
-
-     <para>
-      In the examples that follow, the following table containing JSON data
-      will be used:
-
-<programlisting>
-CREATE TABLE my_films ( js jsonb );
-
-INSERT INTO my_films VALUES (
-'{ "favorites" : [
-   { "kind" : "comedy", "films" : [
-     { "title" : "Bananas",
-       "director" : "Woody Allen"},
-     { "title" : "The Dinner Game",
-       "director" : "Francis Veber" } ] },
-   { "kind" : "horror", "films" : [
-     { "title" : "Psycho",
-       "director" : "Alfred Hitchcock" } ] },
-   { "kind" : "thriller", "films" : [
-     { "title" : "Vertigo",
-       "director" : "Alfred Hitchcock" } ] },
-   { "kind" : "drama", "films" : [
-     { "title" : "Yojimbo",
-       "director" : "Akira Kurosawa" } ] }
-  ] }');
-</programlisting>
-
-     </para>
-     <para>
-      The following query shows how to use <function>JSON_TABLE</function> to
-      turn the JSON objects in the <structname>my_films</structname> table
-      to a view containing columns for the keys <literal>kind</literal>,
-      <literal>title</literal>, and <literal>director</literal> contained in
-      the original JSON along with an ordinality column:
-
-<programlisting>
-SELECT jt.* FROM
- my_films,
- JSON_TABLE (js, '$.favorites[*]' COLUMNS (
-   id FOR ORDINALITY,
-   kind text PATH '$.kind',
-   title text PATH '$.films[*].title' WITH WRAPPER,
-   director text PATH '$.films[*].director' WITH WRAPPER)) AS jt;
-</programlisting>
-
-<screen>
- id |   kind   |             title              |             director
-----+----------+--------------------------------+----------------------------------
-  1 | comedy   | ["Bananas", "The Dinner Game"] | ["Woody Allen", "Francis Veber"]
-  2 | horror   | ["Psycho"]                     | ["Alfred Hitchcock"]
-  3 | thriller | ["Vertigo"]                    | ["Alfred Hitchcock"]
-  4 | drama    | ["Yojimbo"]                    | ["Akira Kurosawa"]
-(4 rows)
-</screen>
-
-     </para>
-     <para>
-      The following is a modified version of the above query to show the
-      usage of <literal>PASSING</literal> arguments in the filter specified in
-      the top-level JSON path expression and the various options for the
-      individual columns:
-
-<programlisting>
-SELECT jt.* FROM
- my_films,
- JSON_TABLE (js, '$.favorites[*] ? (@.films[*].director == $filter)'
-   PASSING 'Alfred Hitchcock' AS filter
-     COLUMNS (
-     id FOR ORDINALITY,
-     kind text PATH '$.kind',
-     title text FORMAT JSON PATH '$.films[*].title' OMIT QUOTES,
-     director text PATH '$.films[*].director' KEEP QUOTES)) AS jt;
-</programlisting>
-
-<screen>
- id |   kind   |  title  |      director
-----+----------+---------+--------------------
-  1 | horror   | Psycho  | "Alfred Hitchcock"
-  2 | thriller | Vertigo | "Alfred Hitchcock"
-(2 rows)
-</screen>
-
-     </para>
-     <para>
-      The following is a modified version of the above query to show the usage
-      of <literal>NESTED PATH</literal> for populating title and director
-      columns, illustrating how they are joined to the parent columns id and
-      kind:
-
-<programlisting>
-SELECT jt.* FROM
- my_films,
- JSON_TABLE ( js, '$.favorites[*] ? (@.films[*].director == $filter)'
-   PASSING 'Alfred Hitchcock' AS filter
-   COLUMNS (
-    id FOR ORDINALITY,
-    kind text PATH '$.kind',
-    NESTED PATH '$.films[*]' COLUMNS (
-      title text FORMAT JSON PATH '$.title' OMIT QUOTES,
-      director text PATH '$.director' KEEP QUOTES))) AS jt;
-</programlisting>
-
-<screen>
- id |   kind   |  title  |      director
-----+----------+---------+--------------------
-  1 | horror   | Psycho  | "Alfred Hitchcock"
-  2 | thriller | Vertigo | "Alfred Hitchcock"
-(2 rows)
-</screen>
-
-     </para>
-
-     <para>
-      The following is the same query but without the filter in the root
-      path:
-
-<programlisting>
-SELECT jt.* FROM
- my_films,
- JSON_TABLE ( js, '$.favorites[*]'
-   COLUMNS (
-    id FOR ORDINALITY,
-    kind text PATH '$.kind',
-    NESTED PATH '$.films[*]' COLUMNS (
-      title text FORMAT JSON PATH '$.title' OMIT QUOTES,
-      director text PATH '$.director' KEEP QUOTES))) AS jt;
-</programlisting>
-
-<screen>
- id |   kind   |      title      |      director
-----+----------+-----------------+--------------------
-  1 | comedy   | Bananas         | "Woody Allen"
-  1 | comedy   | The Dinner Game | "Francis Veber"
-  2 | horror   | Psycho          | "Alfred Hitchcock"
-  3 | thriller | Vertigo         | "Alfred Hitchcock"
-  4 | drama    | Yojimbo         | "Akira Kurosawa"
-(5 rows)
-</screen>
-
-     </para>
-
-     <para>
-      The following shows another query using a different <type>JSON</type>
-      object as input.  It shows the UNION "sibling join" between
-      <literal>NESTED</literal> paths <literal>$.movies[*]</literal> and
-      <literal>$.books[*]</literal> and also the usage of
-      <literal>FOR ORDINALITY</literal> column at <literal>NESTED</literal>
-      levels (columns <literal>movie_id</literal>, <literal>book_id</literal>,
-      and <literal>author_id</literal>):
-
-<programlisting>
-SELECT * FROM JSON_TABLE (
-'{"favorites":
-    [{"movies":
-      [{"name": "One", "director": "John Doe"},
-       {"name": "Two", "director": "Don Joe"}],
-     "books":
-      [{"name": "Mystery", "authors": [{"name": "Brown Dan"}]},
-       {"name": "Wonder", "authors": [{"name": "Jun Murakami"}, {"name":"Craig Doe"}]}]
-}]}'::json, '$.favorites[*]'
-COLUMNS (
-  user_id FOR ORDINALITY,
-  NESTED '$.movies[*]'
-    COLUMNS (
-    movie_id FOR ORDINALITY,
-    mname text PATH '$.name',
-    director text),
-  NESTED '$.books[*]'
-    COLUMNS (
-      book_id FOR ORDINALITY,
-      bname text PATH '$.name',
-      NESTED '$.authors[*]'
-        COLUMNS (
-          author_id FOR ORDINALITY,
-          author_name text PATH '$.name'))));
-</programlisting>
-
-<screen>
- user_id | movie_id | mname | director | book_id |  bname  | author_id | author_name
----------+----------+-------+----------+---------+---------+-----------+--------------
-       1 |        1 | One   | John Doe |         |         |           |
-       1 |        2 | Two   | Don Joe  |         |         |           |
-       1 |          |       |          |       1 | Mystery |         1 | Brown Dan
-       1 |          |       |          |       2 | Wonder  |         1 | Jun Murakami
-       1 |          |       |          |       2 | Wonder  |         2 | Craig Doe
-(5 rows)
-</screen>
-
-     </para>
-  </sect2>
- </sect1>
-
- <sect1 id="functions-sequence">
-  <title>Sequence Manipulation Functions</title>
-
-  <indexterm>
-   <primary>sequence</primary>
-  </indexterm>
-
-  <para>
-   This section describes functions for operating on <firstterm>sequence
-   objects</firstterm>, also called sequence generators or just sequences.
-   Sequence objects are special single-row tables created with <xref
-   linkend="sql-createsequence"/>.
-   Sequence objects are commonly used to generate unique identifiers
-   for rows of a table.  The sequence functions, listed in <xref
-   linkend="functions-sequence-table"/>, provide simple, multiuser-safe
-   methods for obtaining successive sequence values from sequence
-   objects.
-  </para>
-
-   <table id="functions-sequence-table">
-    <title>Sequence Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>nextval</primary>
-        </indexterm>
-        <function>nextval</function> ( <type>regclass</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Advances the sequence object to its next value and returns that value.
-        This is done atomically: even if multiple sessions
-        execute <function>nextval</function> concurrently, each will safely
-        receive a distinct sequence value.
-        If the sequence object has been created with default parameters,
-        successive <function>nextval</function> calls will return successive
-        values beginning with 1.  Other behaviors can be obtained by using
-        appropriate parameters in the <xref linkend="sql-createsequence"/>
-        command.
-      </para>
-       <para>
-        This function requires <literal>USAGE</literal>
-        or <literal>UPDATE</literal> privilege on the sequence.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>setval</primary>
-        </indexterm>
-        <function>setval</function> ( <type>regclass</type>, <type>bigint</type> <optional>, <type>boolean</type> </optional> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Sets the sequence object's current value, and optionally
-        its <literal>is_called</literal> flag.  The two-parameter
-        form sets the sequence's <literal>last_value</literal> field to the
-        specified value and sets its <literal>is_called</literal> field to
-        <literal>true</literal>, meaning that the next
-        <function>nextval</function> will advance the sequence before
-        returning a value.  The value that will be reported
-        by <function>currval</function> is also set to the specified value.
-        In the three-parameter form, <literal>is_called</literal> can be set
-        to either <literal>true</literal>
-        or <literal>false</literal>.  <literal>true</literal> has the same
-        effect as the two-parameter form. If it is set
-        to <literal>false</literal>, the next <function>nextval</function>
-        will return exactly the specified value, and sequence advancement
-        commences with the following <function>nextval</function>.
-        Furthermore, the value reported by <function>currval</function> is not
-        changed in this case.  For example,
-<programlisting>
-SELECT setval('myseq', 42);           <lineannotation>Next <function>nextval</function> will return 43</lineannotation>
-SELECT setval('myseq', 42, true);     <lineannotation>Same as above</lineannotation>
-SELECT setval('myseq', 42, false);    <lineannotation>Next <function>nextval</function> will return 42</lineannotation>
-</programlisting>
-        The result returned by <function>setval</function> is just the value of its
-        second argument.
-       </para>
-       <para>
-        This function requires <literal>UPDATE</literal> privilege on the
-        sequence.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>currval</primary>
-        </indexterm>
-        <function>currval</function> ( <type>regclass</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Returns the value most recently obtained
-        by <function>nextval</function> for this sequence in the current
-        session.  (An error is reported if <function>nextval</function> has
-        never been called for this sequence in this session.)  Because this is
-        returning a session-local value, it gives a predictable answer whether
-        or not other sessions have executed <function>nextval</function> since
-        the current session did.
-       </para>
-       <para>
-        This function requires <literal>USAGE</literal>
-        or <literal>SELECT</literal> privilege on the sequence.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>lastval</primary>
-        </indexterm>
-        <function>lastval</function> ()
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Returns the value most recently returned by
-        <function>nextval</function> in the current session. This function is
-        identical to <function>currval</function>, except that instead
-        of taking the sequence name as an argument it refers to whichever
-        sequence <function>nextval</function> was most recently applied to
-        in the current session. It is an error to call
-        <function>lastval</function> if <function>nextval</function>
-        has not yet been called in the current session.
-       </para>
-       <para>
-        This function requires <literal>USAGE</literal>
-        or <literal>SELECT</literal> privilege on the last used sequence.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <caution>
-   <para>
-    To avoid blocking concurrent transactions that obtain numbers from
-    the same sequence, the value obtained by <function>nextval</function>
-    is not reclaimed for re-use if the calling transaction later aborts.
-    This means that transaction aborts or database crashes can result in
-    gaps in the sequence of assigned values.  That can happen without a
-    transaction abort, too.  For example an <command>INSERT</command> with
-    an <literal>ON CONFLICT</literal> clause will compute the to-be-inserted
-    tuple, including doing any required <function>nextval</function>
-    calls, before detecting any conflict that would cause it to follow
-    the <literal>ON CONFLICT</literal> rule instead.
-    Thus, <productname>PostgreSQL</productname> sequence
-    objects <emphasis>cannot be used to obtain <quote>gapless</quote>
-    sequences</emphasis>.
-   </para>
-
-   <para>
-    Likewise, sequence state changes made by <function>setval</function>
-    are immediately visible to other transactions, and are not undone if
-    the calling transaction rolls back.
-   </para>
-
-   <para>
-    If the database cluster crashes before committing a transaction
-    containing a <function>nextval</function>
-    or <function>setval</function> call, the sequence state change might
-    not have made its way to persistent storage, so that it is uncertain
-    whether the sequence will have its original or updated state after the
-    cluster restarts.  This is harmless for usage of the sequence within
-    the database, since other effects of uncommitted transactions will not
-    be visible either.  However, if you wish to use a sequence value for
-    persistent outside-the-database purposes, make sure that the
-    <function>nextval</function> call has been committed before doing so.
-   </para>
-  </caution>
-
-  <para>
-   The sequence to be operated on by a sequence function is specified by
-   a <type>regclass</type> argument, which is simply the OID of the sequence in the
-   <structname>pg_class</structname> system catalog.  You do not have to look up the
-   OID by hand, however, since the <type>regclass</type> data type's input
-   converter will do the work for you.  See <xref linkend="datatype-oid"/>
-   for details.
-  </para>
- </sect1>
-
-
- <sect1 id="functions-conditional">
-  <title>Conditional Expressions</title>
-
-  <indexterm>
-   <primary>CASE</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>conditional expression</primary>
-  </indexterm>
-
-  <para>
-   This section describes the <acronym>SQL</acronym>-compliant conditional expressions
-   available in <productname>PostgreSQL</productname>.
-  </para>
-
-  <tip>
-   <para>
-    If your needs go beyond the capabilities of these conditional
-    expressions, you might want to consider writing a server-side function
-    in a more expressive programming language.
-   </para>
-  </tip>
-
-   <note>
-    <para>
-     Although <token>COALESCE</token>, <token>GREATEST</token>, and
-     <token>LEAST</token> are syntactically similar to functions, they are
-     not ordinary functions, and thus cannot be used with explicit
-     <token>VARIADIC</token> array arguments.
-    </para>
-   </note>
-
-  <sect2 id="functions-case">
-   <title><literal>CASE</literal></title>
-
-  <para>
-   The <acronym>SQL</acronym> <token>CASE</token> expression is a
-   generic conditional expression, similar to if/else statements in
-   other programming languages:
-
-<synopsis>
-CASE WHEN <replaceable>condition</replaceable> THEN <replaceable>result</replaceable>
-     <optional>WHEN ...</optional>
-     <optional>ELSE <replaceable>result</replaceable></optional>
-END
-</synopsis>
-
-   <token>CASE</token> clauses can be used wherever
-   an expression is valid.  Each <replaceable>condition</replaceable> is an
-   expression that returns a <type>boolean</type> result.  If the condition's
-   result is true, the value of the <token>CASE</token> expression is the
-   <replaceable>result</replaceable> that follows the condition, and the
-   remainder of the <token>CASE</token> expression is not processed.  If the
-   condition's result is not true, any subsequent <token>WHEN</token> clauses
-   are examined in the same manner.  If no <token>WHEN</token>
-   <replaceable>condition</replaceable> yields true, the value of the
-   <token>CASE</token> expression is the <replaceable>result</replaceable> of the
-   <token>ELSE</token> clause.  If the <token>ELSE</token> clause is
-   omitted and no condition is true, the result is null.
-  </para>
-
-   <para>
-    An example:
-<screen>
-SELECT * FROM test;
-
- a
----
- 1
- 2
- 3
-
-
-SELECT a,
-       CASE WHEN a=1 THEN 'one'
-            WHEN a=2 THEN 'two'
-            ELSE 'other'
-       END
-    FROM test;
-
- a | case
----+-------
- 1 | one
- 2 | two
- 3 | other
-</screen>
-   </para>
-
-  <para>
-   The data types of all the <replaceable>result</replaceable>
-   expressions must be convertible to a single output type.
-   See <xref linkend="typeconv-union-case"/> for more details.
-  </para>
-
-  <para>
-   There is a <quote>simple</quote> form of <token>CASE</token> expression
-   that is a variant of the general form above:
-
-<synopsis>
-CASE <replaceable>expression</replaceable>
-    WHEN <replaceable>value</replaceable> THEN <replaceable>result</replaceable>
-    <optional>WHEN ...</optional>
-    <optional>ELSE <replaceable>result</replaceable></optional>
-END
-</synopsis>
-
-   The first
-   <replaceable>expression</replaceable> is computed, then compared to
-   each of the <replaceable>value</replaceable> expressions in the
-   <token>WHEN</token> clauses until one is found that is equal to it.  If
-   no match is found, the <replaceable>result</replaceable> of the
-   <token>ELSE</token> clause (or a null value) is returned.  This is similar
-   to the <function>switch</function> statement in C.
-  </para>
-
-   <para>
-    The example above can be written using the simple
-    <token>CASE</token> syntax:
-<screen>
-SELECT a,
-       CASE a WHEN 1 THEN 'one'
-              WHEN 2 THEN 'two'
-              ELSE 'other'
-       END
-    FROM test;
-
- a | case
----+-------
- 1 | one
- 2 | two
- 3 | other
-</screen>
-   </para>
-
-   <para>
-    A <token>CASE</token> expression does not evaluate any subexpressions
-    that are not needed to determine the result.  For example, this is a
-    possible way of avoiding a division-by-zero failure:
-<programlisting>
-SELECT ... WHERE CASE WHEN x &lt;&gt; 0 THEN y/x &gt; 1.5 ELSE false END;
-</programlisting>
-   </para>
-
-   <note>
-    <para>
-     As described in <xref linkend="syntax-express-eval"/>, there are various
-     situations in which subexpressions of an expression are evaluated at
-     different times, so that the principle that <quote><token>CASE</token>
-     evaluates only necessary subexpressions</quote> is not ironclad.  For
-     example a constant <literal>1/0</literal> subexpression will usually result in
-     a division-by-zero failure at planning time, even if it's within
-     a <token>CASE</token> arm that would never be entered at run time.
-    </para>
-   </note>
-  </sect2>
-
-  <sect2 id="functions-coalesce-nvl-ifnull">
-   <title><literal>COALESCE</literal></title>
-
-  <indexterm>
-   <primary>COALESCE</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>NVL</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>IFNULL</primary>
-  </indexterm>
-
-<synopsis>
-<function>COALESCE</function>(<replaceable>value</replaceable> <optional>, ...</optional>)
-</synopsis>
-
-  <para>
-   The <function>COALESCE</function> function returns the first of its
-   arguments that is not null.  Null is returned only if all arguments
-   are null.  It is often used to substitute a default value for
-   null values when data is retrieved for display, for example:
-<programlisting>
-SELECT COALESCE(description, short_description, '(none)') ...
-</programlisting>
-   This returns <varname>description</varname> if it is not null, otherwise
-   <varname>short_description</varname> if it is not null, otherwise <literal>(none)</literal>.
-  </para>
-
-   <para>
-    The arguments must all be convertible to a common data type, which
-    will be the type of the result (see
-    <xref linkend="typeconv-union-case"/> for details).
-   </para>
-
-   <para>
-    Like a <token>CASE</token> expression, <function>COALESCE</function> only
-    evaluates the arguments that are needed to determine the result;
-    that is, arguments to the right of the first non-null argument are
-    not evaluated.  This SQL-standard function provides capabilities similar
-    to <function>NVL</function> and <function>IFNULL</function>, which are used in some other
-    database systems.
-   </para>
-  </sect2>
-
-  <sect2 id="functions-nullif">
-   <title><literal>NULLIF</literal></title>
-
-  <indexterm>
-   <primary>NULLIF</primary>
-  </indexterm>
-
-<synopsis>
-<function>NULLIF</function>(<replaceable>value1</replaceable>, <replaceable>value2</replaceable>)
-</synopsis>
-
-  <para>
-   The <function>NULLIF</function> function returns a null value if
-   <replaceable>value1</replaceable> equals <replaceable>value2</replaceable>;
-   otherwise it returns <replaceable>value1</replaceable>.
-   This can be used to perform the inverse operation of the
-   <function>COALESCE</function> example given above:
-<programlisting>
-SELECT NULLIF(value, '(none)') ...
-</programlisting>
-   In this example, if <literal>value</literal> is <literal>(none)</literal>,
-   null is returned, otherwise the value of <literal>value</literal>
-   is returned.
-  </para>
-
-  <para>
-   The two arguments must be of comparable types.
-   To be specific, they are compared exactly as if you had
-   written <literal><replaceable>value1</replaceable>
-   = <replaceable>value2</replaceable></literal>, so there must be a
-   suitable <literal>=</literal> operator available.
-  </para>
-
-  <para>
-   The result has the same type as the first argument &mdash; but there is
-   a subtlety.  What is actually returned is the first argument of the
-   implied <literal>=</literal> operator, and in some cases that will have
-   been promoted to match the second argument's type.  For
-   example, <literal>NULLIF(1, 2.2)</literal> yields <type>numeric</type>,
-   because there is no <type>integer</type> <literal>=</literal>
-   <type>numeric</type> operator,
-   only <type>numeric</type> <literal>=</literal> <type>numeric</type>.
-  </para>
-
-  </sect2>
-
-  <sect2 id="functions-greatest-least">
-   <title><literal>GREATEST</literal> and <literal>LEAST</literal></title>
-
-  <indexterm>
-   <primary>GREATEST</primary>
-  </indexterm>
-  <indexterm>
-   <primary>LEAST</primary>
-  </indexterm>
-
-<synopsis>
-<function>GREATEST</function>(<replaceable>value</replaceable> <optional>, ...</optional>)
-</synopsis>
-<synopsis>
-<function>LEAST</function>(<replaceable>value</replaceable> <optional>, ...</optional>)
-</synopsis>
-
-   <para>
-    The <function>GREATEST</function> and <function>LEAST</function> functions select the
-    largest or smallest value from a list of any number of expressions.
-    The expressions must all be convertible to a common data type, which
-    will be the type of the result
-    (see <xref linkend="typeconv-union-case"/> for details).
-   </para>
-
-   <para>
-    NULL values in the argument list are ignored.  The result will be NULL
-    only if all the expressions evaluate to NULL.  (This is a deviation from
-    the SQL standard.  According to the standard, the return value is NULL if
-    any argument is NULL.  Some other databases behave this way.)
-   </para>
-  </sect2>
- </sect1>
-
- <sect1 id="functions-array">
-  <title>Array Functions and Operators</title>
-
-  <para>
-   <xref linkend="array-operators-table"/> shows the specialized operators
-   available for array types.
-   In addition to those, the usual comparison operators shown in <xref
-   linkend="functions-comparison-op-table"/> are available for
-   arrays.  The comparison operators compare the array contents
-   element-by-element, using the default B-tree comparison function for
-   the element data type, and sort based on the first difference.
-   In multidimensional arrays the elements are visited in row-major order
-   (last subscript varies most rapidly).
-   If the contents of two arrays are equal but the dimensionality is
-   different, the first difference in the dimensionality information
-   determines the sort order.
-  </para>
-
-   <table id="array-operators-table">
-    <title>Array Operators</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Operator
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyarray</type> <literal>@&gt;</literal> <type>anyarray</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the first array contain the second, that is, does each element
-        appearing in the second array equal some element of the first array?
-        (Duplicates are not treated specially,
-        thus <literal>ARRAY[1]</literal> and <literal>ARRAY[1,1]</literal> are
-        each considered to contain the other.)
-       </para>
-       <para>
-        <literal>ARRAY[1,4,3] @&gt; ARRAY[3,1,3]</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyarray</type> <literal>&lt;@</literal> <type>anyarray</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the first array contained by the second?
-       </para>
-       <para>
-        <literal>ARRAY[2,2,7] &lt;@ ARRAY[1,7,4,2,6]</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyarray</type> <literal>&amp;&amp;</literal> <type>anyarray</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Do the arrays overlap, that is, have any elements in common?
-       </para>
-       <para>
-        <literal>ARRAY[1,4,3] &amp;&amp; ARRAY[2,1]</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anycompatiblearray</type> <literal>||</literal> <type>anycompatiblearray</type>
-        <returnvalue>anycompatiblearray</returnvalue>
-       </para>
-       <para>
-        Concatenates the two arrays.  Concatenating a null or empty array is a
-        no-op; otherwise the arrays must have the same number of dimensions
-        (as illustrated by the first example) or differ in number of
-        dimensions by one (as illustrated by the second).
-        If the arrays are not of identical element types, they will be coerced
-        to a common type (see <xref linkend="typeconv-union-case"/>).
-       </para>
-       <para>
-        <literal>ARRAY[1,2,3] || ARRAY[4,5,6,7]</literal>
-        <returnvalue>{1,2,3,4,5,6,7}</returnvalue>
-       </para>
-       <para>
-        <literal>ARRAY[1,2,3] || ARRAY[[4,5,6],[7,8,9.9]]</literal>
-        <returnvalue>{{1,2,3},{4,5,6},{7,8,9.9}}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anycompatible</type> <literal>||</literal> <type>anycompatiblearray</type>
-        <returnvalue>anycompatiblearray</returnvalue>
-       </para>
-       <para>
-        Concatenates an element onto the front of an array (which must be
-        empty or one-dimensional).
-       </para>
-       <para>
-        <literal>3 || ARRAY[4,5,6]</literal>
-        <returnvalue>{3,4,5,6}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anycompatiblearray</type> <literal>||</literal> <type>anycompatible</type>
-        <returnvalue>anycompatiblearray</returnvalue>
-       </para>
-       <para>
-        Concatenates an element onto the end of an array (which must be
-        empty or one-dimensional).
-       </para>
-       <para>
-        <literal>ARRAY[4,5,6] || 7</literal>
-        <returnvalue>{4,5,6,7}</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <para>
-   See <xref linkend="arrays"/> for more details about array operator
-   behavior.  See <xref linkend="indexes-types"/> for more details about
-   which operators support indexed operations.
-  </para>
-
-  <para>
-   <xref linkend="array-functions-table"/> shows the functions
-   available for use with array types. See <xref linkend="arrays"/>
-   for more information  and examples of the use of these functions.
-  </para>
-
-   <table id="array-functions-table">
-    <title>Array Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_append</primary>
-        </indexterm>
-        <function>array_append</function> ( <type>anycompatiblearray</type>, <type>anycompatible</type> )
-        <returnvalue>anycompatiblearray</returnvalue>
-       </para>
-       <para>
-        Appends an element to the end of an array (same as
-        the <type>anycompatiblearray</type> <literal>||</literal> <type>anycompatible</type>
-        operator).
-       </para>
-       <para>
-        <literal>array_append(ARRAY[1,2], 3)</literal>
-        <returnvalue>{1,2,3}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_cat</primary>
-        </indexterm>
-        <function>array_cat</function> ( <type>anycompatiblearray</type>, <type>anycompatiblearray</type> )
-        <returnvalue>anycompatiblearray</returnvalue>
-       </para>
-       <para>
-        Concatenates two arrays (same as
-        the <type>anycompatiblearray</type> <literal>||</literal> <type>anycompatiblearray</type>
-        operator).
-       </para>
-       <para>
-        <literal>array_cat(ARRAY[1,2,3], ARRAY[4,5])</literal>
-        <returnvalue>{1,2,3,4,5}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_dims</primary>
-        </indexterm>
-        <function>array_dims</function> ( <type>anyarray</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns a text representation of the array's dimensions.
-       </para>
-       <para>
-        <literal>array_dims(ARRAY[[1,2,3], [4,5,6]])</literal>
-        <returnvalue>[1:2][1:3]</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_fill</primary>
-        </indexterm>
-        <function>array_fill</function> ( <type>anyelement</type>, <type>integer[]</type>
-          <optional>, <type>integer[]</type> </optional> )
-        <returnvalue>anyarray</returnvalue>
-       </para>
-       <para>
-        Returns an array filled with copies of the given value, having
-        dimensions of the lengths specified by the second argument.
-        The optional third argument supplies lower-bound values for each
-        dimension (which default to all <literal>1</literal>).
-       </para>
-       <para>
-        <literal>array_fill(11, ARRAY[2,3])</literal>
-        <returnvalue>{{11,11,11},{11,11,11}}</returnvalue>
-       </para>
-       <para>
-        <literal>array_fill(7, ARRAY[3], ARRAY[2])</literal>
-        <returnvalue>[2:4]={7,7,7}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_length</primary>
-        </indexterm>
-        <function>array_length</function> ( <type>anyarray</type>, <type>integer</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the length of the requested array dimension.
-        (Produces NULL instead of 0 for empty or missing array dimensions.)
-       </para>
-       <para>
-        <literal>array_length(array[1,2,3], 1)</literal>
-        <returnvalue>3</returnvalue>
-       </para>
-       <para>
-        <literal>array_length(array[]::int[], 1)</literal>
-        <returnvalue>NULL</returnvalue>
-       </para>
-       <para>
-        <literal>array_length(array['text'], 2)</literal>
-        <returnvalue>NULL</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_lower</primary>
-        </indexterm>
-        <function>array_lower</function> ( <type>anyarray</type>, <type>integer</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the lower bound of the requested array dimension.
-       </para>
-       <para>
-        <literal>array_lower('[0:2]={1,2,3}'::integer[], 1)</literal>
-        <returnvalue>0</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_ndims</primary>
-        </indexterm>
-        <function>array_ndims</function> ( <type>anyarray</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the number of dimensions of the array.
-       </para>
-       <para>
-        <literal>array_ndims(ARRAY[[1,2,3], [4,5,6]])</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_position</primary>
-        </indexterm>
-        <function>array_position</function> ( <type>anycompatiblearray</type>, <type>anycompatible</type> <optional>, <type>integer</type> </optional> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the subscript of the first occurrence of the second argument
-        in the array, or <literal>NULL</literal> if it's not present.
-        If the third argument is given, the search begins at that subscript.
-        The array must be one-dimensional.
-        Comparisons are done using <literal>IS NOT DISTINCT FROM</literal>
-        semantics, so it is possible to search for <literal>NULL</literal>.
-       </para>
-       <para>
-        <literal>array_position(ARRAY['sun', 'mon', 'tue', 'wed', 'thu', 'fri', 'sat'], 'mon')</literal>
-        <returnvalue>2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_positions</primary>
-        </indexterm>
-        <function>array_positions</function> ( <type>anycompatiblearray</type>, <type>anycompatible</type> )
-        <returnvalue>integer[]</returnvalue>
-       </para>
-       <para>
-        Returns an array of the subscripts of all occurrences of the second
-        argument in the array given as first argument.
-        The array must be one-dimensional.
-        Comparisons are done using <literal>IS NOT DISTINCT FROM</literal>
-        semantics, so it is possible to search for <literal>NULL</literal>.
-        <literal>NULL</literal> is returned only if the array
-        is <literal>NULL</literal>; if the value is not found in the array, an
-        empty array is returned.
-       </para>
-       <para>
-        <literal>array_positions(ARRAY['A','A','B','A'], 'A')</literal>
-        <returnvalue>{1,2,4}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_prepend</primary>
-        </indexterm>
-        <function>array_prepend</function> ( <type>anycompatible</type>, <type>anycompatiblearray</type> )
-        <returnvalue>anycompatiblearray</returnvalue>
-       </para>
-       <para>
-        Prepends an element to the beginning of an array (same as
-        the <type>anycompatible</type> <literal>||</literal> <type>anycompatiblearray</type>
-        operator).
-       </para>
-       <para>
-        <literal>array_prepend(1, ARRAY[2,3])</literal>
-        <returnvalue>{1,2,3}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_remove</primary>
-        </indexterm>
-        <function>array_remove</function> ( <type>anycompatiblearray</type>, <type>anycompatible</type> )
-        <returnvalue>anycompatiblearray</returnvalue>
-       </para>
-       <para>
-        Removes all elements equal to the given value from the array.
-        The array must be one-dimensional.
-        Comparisons are done using <literal>IS NOT DISTINCT FROM</literal>
-        semantics, so it is possible to remove <literal>NULL</literal>s.
-       </para>
-       <para>
-        <literal>array_remove(ARRAY[1,2,3,2], 2)</literal>
-        <returnvalue>{1,3}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_replace</primary>
-        </indexterm>
-        <function>array_replace</function> ( <type>anycompatiblearray</type>, <type>anycompatible</type>, <type>anycompatible</type> )
-        <returnvalue>anycompatiblearray</returnvalue>
-       </para>
-       <para>
-        Replaces each array element equal to the second argument with the
-        third argument.
-       </para>
-       <para>
-        <literal>array_replace(ARRAY[1,2,5,4], 5, 3)</literal>
-        <returnvalue>{1,2,3,4}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_reverse</primary>
-        </indexterm>
-        <function>array_reverse</function> ( <type>anyarray</type> )
-        <returnvalue>anyarray</returnvalue>
-       </para>
-       <para>
-        Reverses the first dimension of the array.
-       </para>
-       <para>
-        <literal>array_reverse(ARRAY[[1,2],[3,4],[5,6]])</literal>
-        <returnvalue>{{5,6},{3,4},{1,2}}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_sample</primary>
-        </indexterm>
-        <function>array_sample</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
-        <returnvalue>anyarray</returnvalue>
-       </para>
-       <para>
-        Returns an array of <parameter>n</parameter> items randomly selected
-        from <parameter>array</parameter>.  <parameter>n</parameter> may not
-        exceed the length of <parameter>array</parameter>'s first dimension.
-        If <parameter>array</parameter> is multi-dimensional,
-        an <quote>item</quote> is a slice having a given first subscript.
-       </para>
-       <para>
-        <literal>array_sample(ARRAY[1,2,3,4,5,6], 3)</literal>
-        <returnvalue>{2,6,1}</returnvalue>
-       </para>
-       <para>
-        <literal>array_sample(ARRAY[[1,2],[3,4],[5,6]], 2)</literal>
-        <returnvalue>{{5,6},{1,2}}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_shuffle</primary>
-        </indexterm>
-        <function>array_shuffle</function> ( <type>anyarray</type> )
-        <returnvalue>anyarray</returnvalue>
-       </para>
-       <para>
-        Randomly shuffles the first dimension of the array.
-       </para>
-       <para>
-        <literal>array_shuffle(ARRAY[[1,2],[3,4],[5,6]])</literal>
-        <returnvalue>{{5,6},{1,2},{3,4}}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_sort</primary>
-        </indexterm>
-        <function>array_sort</function> (
-          <parameter>array</parameter> <type>anyarray</type>
-          <optional>, <parameter>descending</parameter> <type>boolean</type>
-          <optional>, <parameter>nulls_first</parameter> <type>boolean</type>
-          </optional></optional> )
-        <returnvalue>anyarray</returnvalue>
-       </para>
-       <para>
-        Sorts the first dimension of the array.
-        The sort order is determined by the default sort ordering of the
-        array's element type; however, if the element type is collatable,
-        the collation to use can be specified by adding
-        a <literal>COLLATE</literal> clause to
-        the <parameter>array</parameter> argument.
-       </para>
-       <para>
-        If <parameter>descending</parameter> is true then sort in
-        descending order, otherwise ascending order.  If omitted, the
-        default is ascending order.
-        If <parameter>nulls_first</parameter> is true then nulls appear
-        before non-null values, otherwise nulls appear after non-null
-        values.
-        If omitted, <parameter>nulls_first</parameter> is taken to have
-        the same value as <parameter>descending</parameter>.
-       </para>
-       <para>
-        <literal>array_sort(ARRAY[[2,4],[2,1],[6,5]])</literal>
-        <returnvalue>{{2,1},{2,4},{6,5}}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm id="function-array-to-string">
-         <primary>array_to_string</primary>
-        </indexterm>
-        <function>array_to_string</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>delimiter</parameter> <type>text</type> <optional>, <parameter>null_string</parameter> <type>text</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts each array element to its text representation, and
-        concatenates those separated by
-        the <parameter>delimiter</parameter> string.
-        If <parameter>null_string</parameter> is given and is
-        not <literal>NULL</literal>, then <literal>NULL</literal> array
-        entries are represented by that string; otherwise, they are omitted.
-        See also <link linkend="function-string-to-array"><function>string_to_array</function></link>.
-       </para>
-       <para>
-        <literal>array_to_string(ARRAY[1, 2, 3, NULL, 5], ',', '*')</literal>
-        <returnvalue>1,2,3,*,5</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_upper</primary>
-        </indexterm>
-        <function>array_upper</function> ( <type>anyarray</type>, <type>integer</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the upper bound of the requested array dimension.
-       </para>
-       <para>
-        <literal>array_upper(ARRAY[1,8,3,7], 1)</literal>
-        <returnvalue>4</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>cardinality</primary>
-        </indexterm>
-        <function>cardinality</function> ( <type>anyarray</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the total number of elements in the array, or 0 if the array
-        is empty.
-       </para>
-       <para>
-        <literal>cardinality(ARRAY[[1,2],[3,4]])</literal>
-        <returnvalue>4</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>trim_array</primary>
-        </indexterm>
-        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
-        <returnvalue>anyarray</returnvalue>
-       </para>
-       <para>
-        Trims an array by removing the last <parameter>n</parameter> elements.
-        If the array is multidimensional, only the first dimension is trimmed.
-       </para>
-       <para>
-        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
-        <returnvalue>{1,2,3,4}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>unnest</primary>
-        </indexterm>
-        <function>unnest</function> ( <type>anyarray</type> )
-        <returnvalue>setof anyelement</returnvalue>
-       </para>
-       <para>
-        Expands an array into a set of rows.
-        The array's elements are read out in storage order.
-       </para>
-       <para>
-        <literal>unnest(ARRAY[1,2])</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- 1
- 2
-</programlisting>
-       </para>
-       <para>
-        <literal>unnest(ARRAY[['foo','bar'],['baz','quux']])</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- foo
- bar
- baz
- quux
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>unnest</function> ( <type>anyarray</type>, <type>anyarray</type> <optional>, ... </optional> )
-        <returnvalue>setof anyelement, anyelement [, ... ]</returnvalue>
-       </para>
-       <para>
-        Expands multiple arrays (possibly of different data types) into a set of
-        rows.  If the arrays are not all the same length then the shorter ones
-        are padded with <literal>NULL</literal>s.  This form is only allowed
-        in a query's FROM clause; see <xref linkend="queries-tablefunctions"/>.
-       </para>
-       <para>
-        <literal>select * from unnest(ARRAY[1,2], ARRAY['foo','bar','baz']) as x(a,b)</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- a |  b
----+-----
- 1 | foo
- 2 | bar
-   | baz
-</programlisting>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    See also <xref linkend="functions-aggregate"/> about the aggregate
-    function <function>array_agg</function> for use with arrays.
-   </para>
-  </sect1>
-
- <sect1 id="functions-range">
-  <title>Range/Multirange Functions and Operators</title>
-
-  <para>
-   See <xref linkend="rangetypes"/> for an overview of range types.
-  </para>
-
-  <para>
-   <xref linkend="range-operators-table"/> shows the specialized operators
-   available for range types.
-   <xref linkend="multirange-operators-table"/> shows the specialized operators
-   available for multirange types.
-   In addition to those, the usual comparison operators shown in
-   <xref linkend="functions-comparison-op-table"/> are available for range
-   and multirange types.  The comparison operators order first by the range lower
-   bounds, and only if those are equal do they compare the upper bounds.  The
-   multirange operators compare each range until one is unequal. This
-   does not usually result in a useful overall ordering, but the operators are
-   provided to allow unique indexes to be constructed on ranges.
-  </para>
-
-   <table id="range-operators-table">
-    <title>Range Operators</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Operator
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>@&gt;</literal> <type>anyrange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the first range contain the second?
-       </para>
-       <para>
-        <literal>int4range(2,4) @&gt; int4range(2,3)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>@&gt;</literal> <type>anyelement</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the range contain the element?
-       </para>
-       <para>
-        <literal>'[2011-01-01,2011-03-01)'::tsrange @&gt; '2011-01-10'::timestamp</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>&lt;@</literal> <type>anyrange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the first range contained by the second?
-       </para>
-       <para>
-        <literal>int4range(2,4) &lt;@ int4range(1,7)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyelement</type> <literal>&lt;@</literal> <type>anyrange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the element contained in the range?
-       </para>
-       <para>
-        <literal>42 &lt;@ int4range(1,7)</literal>
-        <returnvalue>f</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>&amp;&amp;</literal> <type>anyrange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Do the ranges overlap, that is, have any elements in common?
-       </para>
-       <para>
-        <literal>int8range(3,7) &amp;&amp; int8range(4,12)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>&lt;&lt;</literal> <type>anyrange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the first range strictly left of the second?
-       </para>
-       <para>
-        <literal>int8range(1,10) &lt;&lt; int8range(100,110)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>&gt;&gt;</literal> <type>anyrange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the first range strictly right of the second?
-       </para>
-       <para>
-        <literal>int8range(50,60) &gt;&gt; int8range(20,30)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>&amp;&lt;</literal> <type>anyrange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the first range not extend to the right of the second?
-       </para>
-       <para>
-        <literal>int8range(1,20) &amp;&lt; int8range(18,20)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>&amp;&gt;</literal> <type>anyrange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the first range not extend to the left of the second?
-       </para>
-       <para>
-        <literal>int8range(7,20) &amp;&gt; int8range(5,10)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>-|-</literal> <type>anyrange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Are the ranges adjacent?
-       </para>
-       <para>
-        <literal>numrange(1.1,2.2) -|- numrange(2.2,3.3)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>+</literal> <type>anyrange</type>
-        <returnvalue>anyrange</returnvalue>
-       </para>
-       <para>
-        Computes the union of the ranges.  The ranges must overlap or be
-        adjacent, so that the union is a single range (but
-        see <function>range_merge()</function>).
-       </para>
-       <para>
-        <literal>numrange(5,15) + numrange(10,20)</literal>
-        <returnvalue>[5,20)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>*</literal> <type>anyrange</type>
-        <returnvalue>anyrange</returnvalue>
-       </para>
-       <para>
-        Computes the intersection of the ranges.
-       </para>
-       <para>
-        <literal>int8range(5,15) * int8range(10,20)</literal>
-        <returnvalue>[10,15)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>-</literal> <type>anyrange</type>
-        <returnvalue>anyrange</returnvalue>
-       </para>
-       <para>
-        Computes the difference of the ranges.  The second range must not be
-        contained in the first in such a way that the difference would not be
-        a single range.
-       </para>
-       <para>
-        <literal>int8range(5,15) - int8range(10,20)</literal>
-        <returnvalue>[5,10)</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <table id="multirange-operators-table">
-    <title>Multirange Operators</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Operator
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>@&gt;</literal> <type>anymultirange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the first multirange contain the second?
-       </para>
-       <para>
-        <literal>'{[2,4)}'::int4multirange @&gt; '{[2,3)}'::int4multirange</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>@&gt;</literal> <type>anyrange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the multirange contain the range?
-       </para>
-       <para>
-        <literal>'{[2,4)}'::int4multirange @&gt; int4range(2,3)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>@&gt;</literal> <type>anyelement</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the multirange contain the element?
-       </para>
-       <para>
-        <literal>'{[2011-01-01,2011-03-01)}'::tsmultirange @&gt; '2011-01-10'::timestamp</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>@&gt;</literal> <type>anymultirange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the range contain the multirange?
-       </para>
-       <para>
-        <literal>'[2,4)'::int4range @&gt; '{[2,3)}'::int4multirange</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>&lt;@</literal> <type>anymultirange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the first multirange contained by the second?
-       </para>
-       <para>
-        <literal>'{[2,4)}'::int4multirange &lt;@ '{[1,7)}'::int4multirange</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>&lt;@</literal> <type>anyrange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the multirange contained by the range?
-       </para>
-       <para>
-        <literal>'{[2,4)}'::int4multirange &lt;@ int4range(1,7)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>&lt;@</literal> <type>anymultirange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the range contained by the multirange?
-       </para>
-       <para>
-        <literal>int4range(2,4) &lt;@ '{[1,7)}'::int4multirange</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyelement</type> <literal>&lt;@</literal> <type>anymultirange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the element contained by the multirange?
-       </para>
-       <para>
-        <literal>4 &lt;@ '{[1,7)}'::int4multirange</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>&amp;&amp;</literal> <type>anymultirange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Do the multiranges overlap, that is, have any elements in common?
-       </para>
-       <para>
-        <literal>'{[3,7)}'::int8multirange &amp;&amp; '{[4,12)}'::int8multirange</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>&amp;&amp;</literal> <type>anyrange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the multirange overlap the range?
-       </para>
-       <para>
-        <literal>'{[3,7)}'::int8multirange &amp;&amp; int8range(4,12)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>&amp;&amp;</literal> <type>anymultirange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the range overlap the multirange?
-       </para>
-       <para>
-        <literal>int8range(3,7) &amp;&amp; '{[4,12)}'::int8multirange</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>&lt;&lt;</literal> <type>anymultirange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the first multirange strictly left of the second?
-       </para>
-       <para>
-        <literal>'{[1,10)}'::int8multirange &lt;&lt; '{[100,110)}'::int8multirange</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>&lt;&lt;</literal> <type>anyrange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the multirange strictly left of the range?
-       </para>
-       <para>
-        <literal>'{[1,10)}'::int8multirange &lt;&lt; int8range(100,110)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>&lt;&lt;</literal> <type>anymultirange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the range strictly left of the multirange?
-       </para>
-       <para>
-        <literal>int8range(1,10) &lt;&lt; '{[100,110)}'::int8multirange</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>&gt;&gt;</literal> <type>anymultirange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the first multirange strictly right of the second?
-       </para>
-       <para>
-        <literal>'{[50,60)}'::int8multirange &gt;&gt; '{[20,30)}'::int8multirange</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>&gt;&gt;</literal> <type>anyrange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the multirange strictly right of the range?
-       </para>
-       <para>
-        <literal>'{[50,60)}'::int8multirange &gt;&gt; int8range(20,30)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>&gt;&gt;</literal> <type>anymultirange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the range strictly right of the multirange?
-       </para>
-       <para>
-        <literal>int8range(50,60) &gt;&gt; '{[20,30)}'::int8multirange</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>&amp;&lt;</literal> <type>anymultirange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the first multirange not extend to the right of the second?
-       </para>
-       <para>
-        <literal>'{[1,20)}'::int8multirange &amp;&lt; '{[18,20)}'::int8multirange</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>&amp;&lt;</literal> <type>anyrange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the multirange not extend to the right of the range?
-       </para>
-       <para>
-        <literal>'{[1,20)}'::int8multirange &amp;&lt; int8range(18,20)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>&amp;&lt;</literal> <type>anymultirange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the range not extend to the right of the multirange?
-       </para>
-       <para>
-        <literal>int8range(1,20) &amp;&lt; '{[18,20)}'::int8multirange</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>&amp;&gt;</literal> <type>anymultirange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the first multirange not extend to the left of the second?
-       </para>
-       <para>
-        <literal>'{[7,20)}'::int8multirange &amp;&gt; '{[5,10)}'::int8multirange</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>&amp;&gt;</literal> <type>anyrange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the multirange not extend to the left of the range?
-       </para>
-       <para>
-        <literal>'{[7,20)}'::int8multirange &amp;&gt; int8range(5,10)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>&amp;&gt;</literal> <type>anymultirange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the range not extend to the left of the multirange?
-       </para>
-       <para>
-        <literal>int8range(7,20) &amp;&gt; '{[5,10)}'::int8multirange</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>-|-</literal> <type>anymultirange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Are the multiranges adjacent?
-       </para>
-       <para>
-        <literal>'{[1.1,2.2)}'::nummultirange -|- '{[2.2,3.3)}'::nummultirange</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>-|-</literal> <type>anyrange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the multirange adjacent to the range?
-       </para>
-       <para>
-        <literal>'{[1.1,2.2)}'::nummultirange -|- numrange(2.2,3.3)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anyrange</type> <literal>-|-</literal> <type>anymultirange</type>
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the range adjacent to the multirange?
-       </para>
-       <para>
-        <literal>numrange(1.1,2.2) -|- '{[2.2,3.3)}'::nummultirange</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>+</literal> <type>anymultirange</type>
-        <returnvalue>anymultirange</returnvalue>
-       </para>
-       <para>
-        Computes the union of the multiranges.  The multiranges need not overlap
-        or be adjacent.
-       </para>
-       <para>
-        <literal>'{[5,10)}'::nummultirange + '{[15,20)}'::nummultirange</literal>
-        <returnvalue>{[5,10), [15,20)}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>*</literal> <type>anymultirange</type>
-        <returnvalue>anymultirange</returnvalue>
-       </para>
-       <para>
-        Computes the intersection of the multiranges.
-       </para>
-       <para>
-        <literal>'{[5,15)}'::int8multirange * '{[10,20)}'::int8multirange</literal>
-        <returnvalue>{[10,15)}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <type>anymultirange</type> <literal>-</literal> <type>anymultirange</type>
-        <returnvalue>anymultirange</returnvalue>
-       </para>
-       <para>
-        Computes the difference of the multiranges.
-       </para>
-       <para>
-        <literal>'{[5,20)}'::int8multirange - '{[10,15)}'::int8multirange</literal>
-        <returnvalue>{[5,10), [15,20)}</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <para>
-   The left-of/right-of/adjacent operators always return false when an empty
-   range or multirange is involved; that is, an empty range is not considered to
-   be either before or after any other range.
-  </para>
-
-  <para>
-   Elsewhere empty ranges and multiranges are treated as the additive identity:
-   anything unioned with an empty value is itself. Anything minus an empty
-   value is itself. An empty multirange has exactly the same points as an empty
-   range. Every range contains the empty range. Every multirange contains as many
-   empty ranges as you like.
-  </para>
-
-  <para>
-   The range union and difference operators will fail if the resulting range would
-   need to contain two disjoint sub-ranges, as such a range cannot be
-   represented. There are separate operators for union and difference that take
-   multirange parameters and return a multirange, and they do not fail even if
-   their arguments are disjoint. So if you need a union or difference operation
-   for ranges that may be disjoint, you can avoid errors by first casting your
-   ranges to multiranges.
-  </para>
-
-  <para>
-   <xref linkend="range-functions-table"/> shows the functions
-   available for use with range types.
-   <xref linkend="multirange-functions-table"/> shows the functions
-   available for use with multirange types.
-  </para>
-
-   <table id="range-functions-table">
-    <title>Range Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>lower</primary>
-        </indexterm>
-        <function>lower</function> ( <type>anyrange</type> )
-        <returnvalue>anyelement</returnvalue>
-       </para>
-       <para>
-        Extracts the lower bound of the range (<literal>NULL</literal> if the
-        range is empty or has no lower bound).
-       </para>
-       <para>
-        <literal>lower(numrange(1.1,2.2))</literal>
-        <returnvalue>1.1</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>upper</primary>
-        </indexterm>
-        <function>upper</function> ( <type>anyrange</type> )
-        <returnvalue>anyelement</returnvalue>
-       </para>
-       <para>
-        Extracts the upper bound of the range (<literal>NULL</literal> if the
-        range is empty or has no upper bound).
-       </para>
-       <para>
-        <literal>upper(numrange(1.1,2.2))</literal>
-        <returnvalue>2.2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>isempty</primary>
-        </indexterm>
-        <function>isempty</function> ( <type>anyrange</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the range empty?
-       </para>
-       <para>
-        <literal>isempty(numrange(1.1,2.2))</literal>
-        <returnvalue>f</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>lower_inc</primary>
-        </indexterm>
-        <function>lower_inc</function> ( <type>anyrange</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the range's lower bound inclusive?
-       </para>
-       <para>
-        <literal>lower_inc(numrange(1.1,2.2))</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>upper_inc</primary>
-        </indexterm>
-        <function>upper_inc</function> ( <type>anyrange</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the range's upper bound inclusive?
-       </para>
-       <para>
-        <literal>upper_inc(numrange(1.1,2.2))</literal>
-        <returnvalue>f</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>lower_inf</primary>
-        </indexterm>
-        <function>lower_inf</function> ( <type>anyrange</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the range have no lower bound?  (A lower bound of
-        <literal>-Infinity</literal> returns false.)
-       </para>
-       <para>
-        <literal>lower_inf('(,)'::daterange)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>upper_inf</primary>
-        </indexterm>
-        <function>upper_inf</function> ( <type>anyrange</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the range have no upper bound?  (An upper bound of
-        <literal>Infinity</literal> returns false.)
-       </para>
-       <para>
-        <literal>upper_inf('(,)'::daterange)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>range_merge</primary>
-        </indexterm>
-        <function>range_merge</function> ( <type>anyrange</type>, <type>anyrange</type> )
-        <returnvalue>anyrange</returnvalue>
-       </para>
-       <para>
-        Computes the smallest range that includes both of the given ranges.
-       </para>
-       <para>
-        <literal>range_merge('[1,2)'::int4range, '[3,4)'::int4range)</literal>
-        <returnvalue>[1,4)</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <table id="multirange-functions-table">
-    <title>Multirange Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>lower</primary>
-        </indexterm>
-        <function>lower</function> ( <type>anymultirange</type> )
-        <returnvalue>anyelement</returnvalue>
-       </para>
-       <para>
-        Extracts the lower bound of the multirange (<literal>NULL</literal> if the
-        multirange is empty or has no lower bound).
-       </para>
-       <para>
-        <literal>lower('{[1.1,2.2)}'::nummultirange)</literal>
-        <returnvalue>1.1</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>upper</primary>
-        </indexterm>
-        <function>upper</function> ( <type>anymultirange</type> )
-        <returnvalue>anyelement</returnvalue>
-       </para>
-       <para>
-        Extracts the upper bound of the multirange (<literal>NULL</literal> if the
-        multirange is empty or has no upper bound).
-       </para>
-       <para>
-        <literal>upper('{[1.1,2.2)}'::nummultirange)</literal>
-        <returnvalue>2.2</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>isempty</primary>
-        </indexterm>
-        <function>isempty</function> ( <type>anymultirange</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the multirange empty?
-       </para>
-       <para>
-        <literal>isempty('{[1.1,2.2)}'::nummultirange)</literal>
-        <returnvalue>f</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>lower_inc</primary>
-        </indexterm>
-        <function>lower_inc</function> ( <type>anymultirange</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the multirange's lower bound inclusive?
-       </para>
-       <para>
-        <literal>lower_inc('{[1.1,2.2)}'::nummultirange)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>upper_inc</primary>
-        </indexterm>
-        <function>upper_inc</function> ( <type>anymultirange</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the multirange's upper bound inclusive?
-       </para>
-       <para>
-        <literal>upper_inc('{[1.1,2.2)}'::nummultirange)</literal>
-        <returnvalue>f</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>lower_inf</primary>
-        </indexterm>
-        <function>lower_inf</function> ( <type>anymultirange</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the multirange have no lower bound?  (A lower bound of
-        <literal>-Infinity</literal> returns false.)
-       </para>
-       <para>
-        <literal>lower_inf('{(,)}'::datemultirange)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>upper_inf</primary>
-        </indexterm>
-        <function>upper_inf</function> ( <type>anymultirange</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does the multirange have no upper bound?  (An upper bound of
-        <literal>Infinity</literal> returns false.)
-       </para>
-       <para>
-        <literal>upper_inf('{(,)}'::datemultirange)</literal>
-        <returnvalue>t</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>range_merge</primary>
-        </indexterm>
-        <function>range_merge</function> ( <type>anymultirange</type> )
-        <returnvalue>anyrange</returnvalue>
-       </para>
-       <para>
-        Computes the smallest range that includes the entire multirange.
-       </para>
-       <para>
-        <literal>range_merge('{[1,2), [3,4)}'::int4multirange)</literal>
-        <returnvalue>[1,4)</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>multirange (function)</primary>
-        </indexterm>
-        <function>multirange</function> ( <type>anyrange</type> )
-        <returnvalue>anymultirange</returnvalue>
-       </para>
-       <para>
-        Returns a multirange containing just the given range.
-       </para>
-       <para>
-        <literal>multirange('[1,2)'::int4range)</literal>
-        <returnvalue>{[1,2)}</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>unnest</primary>
-         <secondary>for multirange</secondary>
-        </indexterm>
-        <function>unnest</function> ( <type>anymultirange</type> )
-        <returnvalue>setof anyrange</returnvalue>
-       </para>
-       <para>
-        Expands a multirange into a set of ranges in ascending order.
-       </para>
-       <para>
-        <literal>unnest('{[1,2), [3,4)}'::int4multirange)</literal>
-        <returnvalue></returnvalue>
-<programlisting>
- [1,2)
- [3,4)
-</programlisting>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <para>
-   The <function>lower_inc</function>, <function>upper_inc</function>,
-   <function>lower_inf</function>, and <function>upper_inf</function>
-   functions all return false for an empty range or multirange.
-  </para>
-  </sect1>
-
- <sect1 id="functions-aggregate">
-  <title>Aggregate Functions</title>
-
-  <indexterm zone="functions-aggregate">
-   <primary>aggregate function</primary>
-   <secondary>built-in</secondary>
-  </indexterm>
-
-  <para>
-   <firstterm>Aggregate functions</firstterm> compute a single result
-   from a set of input values.  The built-in general-purpose aggregate
-   functions are listed in <xref linkend="functions-aggregate-table"/>
-   while statistical aggregates are in <xref
-   linkend="functions-aggregate-statistics-table"/>.
-   The built-in within-group ordered-set aggregate functions
-   are listed in <xref linkend="functions-orderedset-table"/>
-   while the built-in within-group hypothetical-set ones are in <xref
-   linkend="functions-hypothetical-table"/>.  Grouping operations,
-   which are closely related to aggregate functions, are listed in
-   <xref linkend="functions-grouping-table"/>.
-   The special syntax considerations for aggregate
-   functions are explained in <xref linkend="syntax-aggregates"/>.
-   Consult <xref linkend="tutorial-agg"/> for additional introductory
-   information.
-  </para>
-
-  <para>
-   Aggregate functions that support <firstterm>Partial Mode</firstterm>
-   are eligible to participate in various optimizations, such as parallel
-   aggregation.
-  </para>
-
-  <para>
-   While all aggregates below accept an optional
-   <literal>ORDER BY</literal> clause (as outlined in <xref
-   linkend="syntax-aggregates"/>), the clause has only been added to
-   aggregates whose output is affected by ordering.
-  </para>
-
-   <table id="functions-aggregate-table">
-    <title>General-Purpose Aggregate Functions</title>
-    <tgroup cols="2">
-     <colspec colname="col1" colwidth="10*"/>
-     <colspec colname="col2" colwidth="1*"/>
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-       <entry>Partial Mode</entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>any_value</primary>
-        </indexterm>
-        <function>any_value</function> ( <type>anyelement</type> )
-        <returnvalue><replaceable>same as input type</replaceable></returnvalue>
-       </para>
-       <para>
-        Returns an arbitrary value from the non-null input values.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>array_agg</primary>
-        </indexterm>
-        <function>array_agg</function> ( <type>anynonarray</type> <literal>ORDER BY</literal> <literal>input_sort_columns</literal> )
-        <returnvalue>anyarray</returnvalue>
-       </para>
-       <para>
-        Collects all the input values, including nulls, into an array.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>array_agg</function> ( <type>anyarray</type> <literal>ORDER BY</literal> <literal>input_sort_columns</literal> )
-        <returnvalue>anyarray</returnvalue>
-       </para>
-       <para>
-        Concatenates all the input arrays into an array of one higher
-        dimension.  (The inputs must all have the same dimensionality, and
-        cannot be empty or null.)
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>average</primary>
-        </indexterm>
-        <indexterm>
-         <primary>avg</primary>
-        </indexterm>
-        <function>avg</function> ( <type>smallint</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>avg</function> ( <type>integer</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>avg</function> ( <type>bigint</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>avg</function> ( <type>numeric</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>avg</function> ( <type>real</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>avg</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>avg</function> ( <type>interval</type> )
-        <returnvalue>interval</returnvalue>
-       </para>
-       <para>
-        Computes the average (arithmetic mean) of all the non-null input
-        values.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>bit_and</primary>
-        </indexterm>
-        <function>bit_and</function> ( <type>smallint</type> )
-        <returnvalue>smallint</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>bit_and</function> ( <type>integer</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>bit_and</function> ( <type>bigint</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>bit_and</function> ( <type>bit</type> )
-        <returnvalue>bit</returnvalue>
-       </para>
-       <para>
-        Computes the bitwise AND of all non-null input values.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>bit_or</primary>
-        </indexterm>
-        <function>bit_or</function> ( <type>smallint</type> )
-        <returnvalue>smallint</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>bit_or</function> ( <type>integer</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>bit_or</function> ( <type>bigint</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>bit_or</function> ( <type>bit</type> )
-        <returnvalue>bit</returnvalue>
-       </para>
-       <para>
-        Computes the bitwise OR of all non-null input values.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>bit_xor</primary>
-        </indexterm>
-        <function>bit_xor</function> ( <type>smallint</type> )
-        <returnvalue>smallint</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>bit_xor</function> ( <type>integer</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>bit_xor</function> ( <type>bigint</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>bit_xor</function> ( <type>bit</type> )
-        <returnvalue>bit</returnvalue>
-       </para>
-       <para>
-        Computes the bitwise exclusive OR of all non-null input values.
-        Can be useful as a checksum for an unordered set of values.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>bool_and</primary>
-        </indexterm>
-        <function>bool_and</function> ( <type>boolean</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Returns true if all non-null input values are true, otherwise false.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>bool_or</primary>
-        </indexterm>
-        <function>bool_or</function> ( <type>boolean</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Returns true if any non-null input value is true, otherwise false.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>count</primary>
-        </indexterm>
-        <function>count</function> ( <literal>*</literal> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Computes the number of input rows.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>count</function> ( <type>"any"</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Computes the number of input rows in which the input value is not
-        null.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>every</primary>
-        </indexterm>
-        <function>every</function> ( <type>boolean</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        This is the SQL standard's equivalent to <function>bool_and</function>.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_agg</primary>
-        </indexterm>
-        <function>json_agg</function> ( <type>anyelement</type> <literal>ORDER BY</literal> <literal>input_sort_columns</literal> )
-        <returnvalue>json</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_agg</primary>
-        </indexterm>
-        <function>jsonb_agg</function> ( <type>anyelement</type> <literal>ORDER BY</literal> <literal>input_sort_columns</literal> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Collects all the input values, including nulls, into a JSON array.
-        Values are converted to JSON as per <function>to_json</function>
-        or <function>to_jsonb</function>.
-       </para></entry>
-       <entry>No</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_agg_strict</primary>
-        </indexterm>
-        <function>json_agg_strict</function> ( <type>anyelement</type> )
-        <returnvalue>json</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_agg_strict</primary>
-        </indexterm>
-        <function>jsonb_agg_strict</function> ( <type>anyelement</type> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Collects all the input values, skipping nulls, into a JSON array.
-        Values are converted to JSON as per <function>to_json</function>
-        or <function>to_jsonb</function>.
-       </para></entry>
-       <entry>No</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm><primary>json_arrayagg</primary></indexterm>
-        <function>json_arrayagg</function> (
-        <optional> <replaceable>value_expression</replaceable> </optional>
-        <optional> <literal>ORDER BY</literal> <replaceable>sort_expression</replaceable> </optional>
-        <optional> { <literal>NULL</literal> | <literal>ABSENT</literal> } <literal>ON NULL</literal> </optional>
-        <optional> <literal>RETURNING</literal> <replaceable>data_type</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional> </optional>)
-       </para>
-       <para>
-        Behaves in the same way as <function>json_array</function>
-        but as an aggregate function so it only takes one
-        <replaceable>value_expression</replaceable> parameter.
-        If <literal>ABSENT ON NULL</literal> is specified, any NULL
-        values are omitted.
-        If <literal>ORDER BY</literal> is specified, the elements will
-        appear in the array in that order rather than in the input order.
-       </para>
-       <para>
-        <literal>SELECT json_arrayagg(v) FROM (VALUES(2),(1)) t(v)</literal>
-        <returnvalue>[2, 1]</returnvalue>
-       </para></entry>
-       <entry>No</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-         <indexterm><primary>json_objectagg</primary></indexterm>
-         <function>json_objectagg</function> (
-         <optional> { <replaceable>key_expression</replaceable> { <literal>VALUE</literal> | ':' } <replaceable>value_expression</replaceable> } </optional>
-         <optional> { <literal>NULL</literal> | <literal>ABSENT</literal> } <literal>ON NULL</literal> </optional>
-        <optional> { <literal>WITH</literal> | <literal>WITHOUT</literal> } <literal>UNIQUE</literal> <optional> <literal>KEYS</literal> </optional> </optional>
-        <optional> <literal>RETURNING</literal> <replaceable>data_type</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional> </optional>)
-        </para>
-        <para>
-         Behaves like <function>json_object</function><!-- xref -->, but as an
-         aggregate function, so it only takes one
-         <replaceable>key_expression</replaceable> and one
-         <replaceable>value_expression</replaceable> parameter.
-        </para>
-        <para>
-         <literal>SELECT json_objectagg(k:v) FROM (VALUES ('a'::text,current_date),('b',current_date + 1)) AS t(k,v)</literal>
-         <returnvalue>{ "a" : "2022-05-10", "b" : "2022-05-11" }</returnvalue>
-       </para></entry>
-       <entry>No</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_object_agg</primary>
-        </indexterm>
-        <function>json_object_agg</function> ( <parameter>key</parameter>
-         <type>"any"</type>, <parameter>value</parameter>
-         <type>"any"</type>
-         <literal>ORDER BY</literal> <literal>input_sort_columns</literal> )
-        <returnvalue>json</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_object_agg</primary>
-        </indexterm>
-        <function>jsonb_object_agg</function> ( <parameter>key</parameter>
-         <type>"any"</type>, <parameter>value</parameter>
-         <type>"any"</type>
-         <literal>ORDER BY</literal> <literal>input_sort_columns</literal> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Collects all the key/value pairs into a JSON object.  Key arguments
-        are coerced to text; value arguments are converted as per
-        <function>to_json</function> or <function>to_jsonb</function>.
-        Values can be null, but keys cannot.
-       </para></entry>
-       <entry>No</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_object_agg_strict</primary>
-        </indexterm>
-        <function>json_object_agg_strict</function> (
-         <parameter>key</parameter> <type>"any"</type>,
-         <parameter>value</parameter> <type>"any"</type> )
-        <returnvalue>json</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_object_agg_strict</primary>
-        </indexterm>
-        <function>jsonb_object_agg_strict</function> (
-         <parameter>key</parameter> <type>"any"</type>,
-         <parameter>value</parameter> <type>"any"</type> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Collects all the key/value pairs into a JSON object.  Key arguments
-        are coerced to text; value arguments are converted as per
-        <function>to_json</function> or <function>to_jsonb</function>.
-        The <parameter>key</parameter> can not be null. If the
-        <parameter>value</parameter> is null then the entry is skipped,
-       </para></entry>
-       <entry>No</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_object_agg_unique</primary>
-        </indexterm>
-        <function>json_object_agg_unique</function> (
-         <parameter>key</parameter> <type>"any"</type>,
-         <parameter>value</parameter> <type>"any"</type> )
-        <returnvalue>json</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_object_agg_unique</primary>
-        </indexterm>
-        <function>jsonb_object_agg_unique</function> (
-         <parameter>key</parameter> <type>"any"</type>,
-         <parameter>value</parameter> <type>"any"</type> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Collects all the key/value pairs into a JSON object.  Key arguments
-        are coerced to text; value arguments are converted as per
-        <function>to_json</function> or <function>to_jsonb</function>.
-        Values can be null, but keys cannot.
-        If there is a duplicate key an error is thrown.
-       </para></entry>
-       <entry>No</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>json_object_agg_unique_strict</primary>
-        </indexterm>
-        <function>json_object_agg_unique_strict</function> (
-         <parameter>key</parameter> <type>"any"</type>,
-         <parameter>value</parameter> <type>"any"</type> )
-        <returnvalue>json</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>jsonb_object_agg_unique_strict</primary>
-        </indexterm>
-        <function>jsonb_object_agg_unique_strict</function> (
-         <parameter>key</parameter> <type>"any"</type>,
-         <parameter>value</parameter> <type>"any"</type> )
-        <returnvalue>jsonb</returnvalue>
-       </para>
-       <para>
-        Collects all the key/value pairs into a JSON object.  Key arguments
-        are coerced to text; value arguments are converted as per
-        <function>to_json</function> or <function>to_jsonb</function>.
-        The <parameter>key</parameter> can not be null. If the
-        <parameter>value</parameter> is null then the entry is skipped.
-        If there is a duplicate key an error is thrown.
-       </para></entry>
-       <entry>No</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>max</primary>
-        </indexterm>
-        <function>max</function> ( <replaceable>see text</replaceable> )
-        <returnvalue><replaceable>same as input type</replaceable></returnvalue>
-       </para>
-       <para>
-        Computes the maximum of the non-null input
-        values.  Available for any numeric, string, date/time, or enum type,
-        as well as <type>bytea</type>, <type>inet</type>, <type>interval</type>,
-        <type>money</type>, <type>oid</type>, <type>pg_lsn</type>,
-        <type>tid</type>, <type>xid8</type>,
-        and also arrays and composite types containing sortable data types.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>min</primary>
-        </indexterm>
-        <function>min</function> ( <replaceable>see text</replaceable> )
-        <returnvalue><replaceable>same as input type</replaceable></returnvalue>
-       </para>
-       <para>
-        Computes the minimum of the non-null input
-        values.  Available for any numeric, string, date/time, or enum type,
-        as well as <type>bytea</type>, <type>inet</type>, <type>interval</type>,
-        <type>money</type>, <type>oid</type>, <type>pg_lsn</type>,
-        <type>tid</type>, <type>xid8</type>,
-        and also arrays and composite types containing sortable data types.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>range_agg</primary>
-        </indexterm>
-        <function>range_agg</function> ( <parameter>value</parameter>
-         <type>anyrange</type> )
-        <returnvalue>anymultirange</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>range_agg</function> ( <parameter>value</parameter>
-         <type>anymultirange</type> )
-        <returnvalue>anymultirange</returnvalue>
-       </para>
-       <para>
-        Computes the union of the non-null input values.
-       </para></entry>
-       <entry>No</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>range_intersect_agg</primary>
-        </indexterm>
-        <function>range_intersect_agg</function> ( <parameter>value</parameter>
-         <type>anyrange</type> )
-        <returnvalue>anyrange</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>range_intersect_agg</function> ( <parameter>value</parameter>
-         <type>anymultirange</type> )
-        <returnvalue>anymultirange</returnvalue>
-       </para>
-       <para>
-        Computes the intersection of the non-null input values.
-       </para></entry>
-       <entry>No</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>string_agg</primary>
-        </indexterm>
-        <function>string_agg</function> ( <parameter>value</parameter>
-         <type>text</type>, <parameter>delimiter</parameter> <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>string_agg</function> ( <parameter>value</parameter>
-         <type>bytea</type>, <parameter>delimiter</parameter> <type>bytea</type>
-         <literal>ORDER BY</literal> <literal>input_sort_columns</literal> )
-        <returnvalue>bytea</returnvalue>
-       </para>
-       <para>
-        Concatenates the non-null input values into a string.  Each value
-        after the first is preceded by the
-        corresponding <parameter>delimiter</parameter> (if it's not null).
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>sum</primary>
-        </indexterm>
-        <function>sum</function> ( <type>smallint</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>sum</function> ( <type>integer</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>sum</function> ( <type>bigint</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>sum</function> ( <type>numeric</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>sum</function> ( <type>real</type> )
-        <returnvalue>real</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>sum</function> ( <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>sum</function> ( <type>interval</type> )
-        <returnvalue>interval</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>sum</function> ( <type>money</type> )
-        <returnvalue>money</returnvalue>
-       </para>
-       <para>
-        Computes the sum of the non-null input values.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>xmlagg</primary>
-        </indexterm>
-        <function>xmlagg</function> ( <type>xml</type> <literal>ORDER BY</literal> <literal>input_sort_columns</literal> )
-        <returnvalue>xml</returnvalue>
-       </para>
-       <para>
-        Concatenates the non-null XML input values (see
-        <xref linkend="functions-xml-xmlagg"/>).
-       </para></entry>
-       <entry>No</entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <para>
-   It should be noted that except for <function>count</function>,
-   these functions return a null value when no rows are selected.  In
-   particular, <function>sum</function> of no rows returns null, not
-   zero as one might expect, and <function>array_agg</function>
-   returns null rather than an empty array when there are no input
-   rows.  The <function>coalesce</function> function can be used to
-   substitute zero or an empty array for null when necessary.
-  </para>
-
-  <para>
-   The aggregate functions <function>array_agg</function>,
-   <function>json_agg</function>, <function>jsonb_agg</function>,
-   <function>json_agg_strict</function>, <function>jsonb_agg_strict</function>,
-   <function>json_object_agg</function>, <function>jsonb_object_agg</function>,
-   <function>json_object_agg_strict</function>, <function>jsonb_object_agg_strict</function>,
-   <function>json_object_agg_unique</function>, <function>jsonb_object_agg_unique</function>,
-   <function>json_object_agg_unique_strict</function>,
-   <function>jsonb_object_agg_unique_strict</function>,
-   <function>string_agg</function>,
-   and <function>xmlagg</function>, as well as similar user-defined
-   aggregate functions, produce meaningfully different result values
-   depending on the order of the input values.  This ordering is
-   unspecified by default, but can be controlled by writing an
-   <literal>ORDER BY</literal> clause within the aggregate call, as shown in
-   <xref linkend="syntax-aggregates"/>.
-   Alternatively, supplying the input values from a sorted subquery
-   will usually work.  For example:
-
-<screen><![CDATA[
-SELECT xmlagg(x) FROM (SELECT x FROM test ORDER BY y DESC) AS tab;
-]]></screen>
-
-   Beware that this approach can fail if the outer query level contains
-   additional processing, such as a join, because that might cause the
-   subquery's output to be reordered before the aggregate is computed.
-  </para>
-
-  <note>
-    <indexterm>
-      <primary>ANY</primary>
-    </indexterm>
-    <indexterm>
-      <primary>SOME</primary>
-    </indexterm>
-    <para>
-      The boolean aggregates <function>bool_and</function> and
-      <function>bool_or</function> correspond to the standard SQL aggregates
-      <function>every</function> and <function>any</function> or
-      <function>some</function>.
-      <productname>PostgreSQL</productname>
-      supports <function>every</function>, but not <function>any</function>
-      or <function>some</function>, because there is an ambiguity built into
-      the standard syntax:
-<programlisting>
-SELECT b1 = ANY((SELECT b2 FROM t2 ...)) FROM t1 ...;
-</programlisting>
-      Here <function>ANY</function> can be considered either as introducing
-      a subquery, or as being an aggregate function, if the subquery
-      returns one row with a Boolean value.
-      Thus the standard name cannot be given to these aggregates.
-    </para>
-  </note>
-
-  <note>
-   <para>
-    Users accustomed to working with other SQL database management
-    systems might be disappointed by the performance of the
-    <function>count</function> aggregate when it is applied to the
-    entire table. A query like:
-<programlisting>
-SELECT count(*) FROM sometable;
-</programlisting>
-    will require effort proportional to the size of the table:
-    <productname>PostgreSQL</productname> will need to scan either the
-    entire table or the entirety of an index that includes all rows in
-    the table.
-   </para>
-  </note>
-
-  <para>
-   <xref linkend="functions-aggregate-statistics-table"/> shows
-   aggregate functions typically used in statistical analysis.
-   (These are separated out merely to avoid cluttering the listing
-   of more-commonly-used aggregates.)  Functions shown as
-   accepting <replaceable>numeric_type</replaceable> are available for all
-   the types <type>smallint</type>, <type>integer</type>,
-   <type>bigint</type>, <type>numeric</type>, <type>real</type>,
-   and <type>double precision</type>.
-   Where the description mentions
-   <parameter>N</parameter>, it means the
-   number of input rows for which all the input expressions are non-null.
-   In all cases, null is returned if the computation is meaningless,
-   for example when <parameter>N</parameter> is zero.
-  </para>
-
-  <indexterm>
-   <primary>statistics</primary>
-  </indexterm>
-  <indexterm>
-   <primary>linear regression</primary>
-  </indexterm>
-
-   <table id="functions-aggregate-statistics-table">
-    <title>Aggregate Functions for Statistics</title>
-    <tgroup cols="2">
-     <colspec colname="col1" colwidth="10*"/>
-     <colspec colname="col2" colwidth="1*"/>
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-       <entry>Partial Mode</entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>correlation</primary>
-        </indexterm>
-        <indexterm>
-         <primary>corr</primary>
-        </indexterm>
-        <function>corr</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes the correlation coefficient.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>covariance</primary>
-         <secondary>population</secondary>
-        </indexterm>
-        <indexterm>
-         <primary>covar_pop</primary>
-        </indexterm>
-        <function>covar_pop</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes the population covariance.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>covariance</primary>
-         <secondary>sample</secondary>
-        </indexterm>
-        <indexterm>
-         <primary>covar_samp</primary>
-        </indexterm>
-        <function>covar_samp</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes the sample covariance.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regr_avgx</primary>
-        </indexterm>
-        <function>regr_avgx</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes the average of the independent variable,
-        <literal>sum(<parameter>X</parameter>)/<parameter>N</parameter></literal>.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regr_avgy</primary>
-        </indexterm>
-        <function>regr_avgy</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes the average of the dependent variable,
-        <literal>sum(<parameter>Y</parameter>)/<parameter>N</parameter></literal>.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regr_count</primary>
-        </indexterm>
-        <function>regr_count</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Computes the number of rows in which both inputs are non-null.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regression intercept</primary>
-        </indexterm>
-        <indexterm>
-         <primary>regr_intercept</primary>
-        </indexterm>
-        <function>regr_intercept</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes the y-intercept of the least-squares-fit linear equation
-        determined by the
-        (<parameter>X</parameter>, <parameter>Y</parameter>) pairs.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regr_r2</primary>
-        </indexterm>
-        <function>regr_r2</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes the square of the correlation coefficient.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regression slope</primary>
-        </indexterm>
-        <indexterm>
-         <primary>regr_slope</primary>
-        </indexterm>
-        <function>regr_slope</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes the slope of the least-squares-fit linear equation determined
-        by the (<parameter>X</parameter>, <parameter>Y</parameter>)
-        pairs.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regr_sxx</primary>
-        </indexterm>
-        <function>regr_sxx</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes the <quote>sum of squares</quote> of the independent
-        variable,
-        <literal>sum(<parameter>X</parameter>^2) - sum(<parameter>X</parameter>)^2/<parameter>N</parameter></literal>.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regr_sxy</primary>
-        </indexterm>
-        <function>regr_sxy</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes the <quote>sum of products</quote> of independent times
-        dependent variables,
-        <literal>sum(<parameter>X</parameter>*<parameter>Y</parameter>) - sum(<parameter>X</parameter>) * sum(<parameter>Y</parameter>)/<parameter>N</parameter></literal>.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>regr_syy</primary>
-        </indexterm>
-        <function>regr_syy</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes the <quote>sum of squares</quote> of the dependent
-        variable,
-        <literal>sum(<parameter>Y</parameter>^2) - sum(<parameter>Y</parameter>)^2/<parameter>N</parameter></literal>.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>standard deviation</primary>
-        </indexterm>
-        <indexterm>
-         <primary>stddev</primary>
-        </indexterm>
-        <function>stddev</function> ( <replaceable>numeric_type</replaceable> )
-        <returnvalue></returnvalue> <type>double precision</type>
-        for <type>real</type> or <type>double precision</type>,
-        otherwise <type>numeric</type>
-       </para>
-       <para>
-        This is a historical alias for <function>stddev_samp</function>.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>standard deviation</primary>
-         <secondary>population</secondary>
-        </indexterm>
-        <indexterm>
-         <primary>stddev_pop</primary>
-        </indexterm>
-        <function>stddev_pop</function> ( <replaceable>numeric_type</replaceable> )
-        <returnvalue></returnvalue> <type>double precision</type>
-        for <type>real</type> or <type>double precision</type>,
-        otherwise <type>numeric</type>
-       </para>
-       <para>
-        Computes the population standard deviation of the input values.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>standard deviation</primary>
-         <secondary>sample</secondary>
-        </indexterm>
-        <indexterm>
-         <primary>stddev_samp</primary>
-        </indexterm>
-        <function>stddev_samp</function> ( <replaceable>numeric_type</replaceable> )
-        <returnvalue></returnvalue> <type>double precision</type>
-        for <type>real</type> or <type>double precision</type>,
-        otherwise <type>numeric</type>
-       </para>
-       <para>
-        Computes the sample standard deviation of the input values.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>variance</primary>
-        </indexterm>
-        <function>variance</function> ( <replaceable>numeric_type</replaceable> )
-        <returnvalue></returnvalue> <type>double precision</type>
-        for <type>real</type> or <type>double precision</type>,
-        otherwise <type>numeric</type>
-       </para>
-       <para>
-        This is a historical alias for <function>var_samp</function>.
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>variance</primary>
-         <secondary>population</secondary>
-        </indexterm>
-        <indexterm>
-         <primary>var_pop</primary>
-        </indexterm>
-        <function>var_pop</function> ( <replaceable>numeric_type</replaceable> )
-        <returnvalue></returnvalue> <type>double precision</type>
-        for <type>real</type> or <type>double precision</type>,
-        otherwise <type>numeric</type>
-       </para>
-       <para>
-        Computes the population variance of the input values (square of the
-        population standard deviation).
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>variance</primary>
-         <secondary>sample</secondary>
-        </indexterm>
-        <indexterm>
-         <primary>var_samp</primary>
-        </indexterm>
-        <function>var_samp</function> ( <replaceable>numeric_type</replaceable> )
-        <returnvalue></returnvalue> <type>double precision</type>
-        for <type>real</type> or <type>double precision</type>,
-        otherwise <type>numeric</type>
-       </para>
-       <para>
-        Computes the sample variance of the input values (square of the sample
-        standard deviation).
-       </para></entry>
-       <entry>Yes</entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <para>
-   <xref linkend="functions-orderedset-table"/> shows some
-   aggregate functions that use the <firstterm>ordered-set aggregate</firstterm>
-   syntax.  These functions are sometimes referred to as <quote>inverse
-   distribution</quote> functions.  Their aggregated input is introduced by
-   <literal>ORDER BY</literal>, and they may also take a <firstterm>direct
-   argument</firstterm> that is not aggregated, but is computed only once.
-   All these functions ignore null values in their aggregated input.
-   For those that take a <parameter>fraction</parameter> parameter, the
-   fraction value must be between 0 and 1; an error is thrown if not.
-   However, a null <parameter>fraction</parameter> value simply produces a
-   null result.
-  </para>
-
-  <indexterm>
-   <primary>ordered-set aggregate</primary>
-   <secondary>built-in</secondary>
-  </indexterm>
-  <indexterm>
-   <primary>inverse distribution</primary>
-  </indexterm>
-
-   <table id="functions-orderedset-table">
-    <title>Ordered-Set Aggregate Functions</title>
-    <tgroup cols="2">
-     <colspec colname="col1" colwidth="10*"/>
-     <colspec colname="col2" colwidth="1*"/>
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-       <entry>Partial Mode</entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>mode</primary>
-         <secondary>statistical</secondary>
-        </indexterm>
-        <function>mode</function> () <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <type>anyelement</type> )
-        <returnvalue>anyelement</returnvalue>
-       </para>
-       <para>
-        Computes the <firstterm>mode</firstterm>, the most frequent
-        value of the aggregated argument (arbitrarily choosing the first one
-        if there are multiple equally-frequent values).  The aggregated
-        argument must be of a sortable type.
-       </para></entry>
-       <entry>No</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>percentile</primary>
-         <secondary>continuous</secondary>
-        </indexterm>
-        <function>percentile_cont</function> ( <parameter>fraction</parameter> <type>double precision</type> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <type>double precision</type> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>percentile_cont</function> ( <parameter>fraction</parameter> <type>double precision</type> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <type>interval</type> )
-        <returnvalue>interval</returnvalue>
-       </para>
-       <para>
-        Computes the <firstterm>continuous percentile</firstterm>, a value
-        corresponding to the specified <parameter>fraction</parameter>
-        within the ordered set of aggregated argument values.  This will
-        interpolate between adjacent input items if needed.
-       </para></entry>
-       <entry>No</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>percentile_cont</function> ( <parameter>fractions</parameter> <type>double precision[]</type> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <type>double precision</type> )
-        <returnvalue>double precision[]</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>percentile_cont</function> ( <parameter>fractions</parameter> <type>double precision[]</type> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <type>interval</type> )
-        <returnvalue>interval[]</returnvalue>
-       </para>
-       <para>
-        Computes multiple continuous percentiles.  The result is an array of
-        the same dimensions as the <parameter>fractions</parameter>
-        parameter, with each non-null element replaced by the (possibly
-        interpolated) value corresponding to that percentile.
-       </para></entry>
-       <entry>No</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>percentile</primary>
-         <secondary>discrete</secondary>
-        </indexterm>
-        <function>percentile_disc</function> ( <parameter>fraction</parameter> <type>double precision</type> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <type>anyelement</type> )
-        <returnvalue>anyelement</returnvalue>
-       </para>
-       <para>
-        Computes the <firstterm>discrete percentile</firstterm>, the first
-        value within the ordered set of aggregated argument values whose
-        position in the ordering equals or exceeds the
-        specified <parameter>fraction</parameter>.  The aggregated
-        argument must be of a sortable type.
-       </para></entry>
-       <entry>No</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>percentile_disc</function> ( <parameter>fractions</parameter> <type>double precision[]</type> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <type>anyelement</type> )
-        <returnvalue>anyarray</returnvalue>
-       </para>
-       <para>
-        Computes multiple discrete percentiles.  The result is an array of the
-        same dimensions as the <parameter>fractions</parameter> parameter,
-        with each non-null element replaced by the input value corresponding
-        to that percentile.
-        The aggregated argument must be of a sortable type.
-       </para></entry>
-       <entry>No</entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <indexterm>
-   <primary>hypothetical-set aggregate</primary>
-   <secondary>built-in</secondary>
-  </indexterm>
-
-  <para>
-   Each of the <quote>hypothetical-set</quote> aggregates listed in
-   <xref linkend="functions-hypothetical-table"/> is associated with a
-   window function of the same name defined in
-   <xref linkend="functions-window"/>.  In each case, the aggregate's result
-   is the value that the associated window function would have
-   returned for the <quote>hypothetical</quote> row constructed from
-   <replaceable>args</replaceable>, if such a row had been added to the sorted
-   group of rows represented by the <replaceable>sorted_args</replaceable>.
-   For each of these functions, the list of direct arguments
-   given in <replaceable>args</replaceable> must match the number and types of
-   the aggregated arguments given in <replaceable>sorted_args</replaceable>.
-   Unlike most built-in aggregates, these aggregates are not strict, that is
-   they do not drop input rows containing nulls.  Null values sort according
-   to the rule specified in the <literal>ORDER BY</literal> clause.
-  </para>
-
-   <table id="functions-hypothetical-table">
-    <title>Hypothetical-Set Aggregate Functions</title>
-    <tgroup cols="2">
-     <colspec colname="col1" colwidth="10*"/>
-     <colspec colname="col2" colwidth="1*"/>
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-       <entry>Partial Mode</entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>rank</primary>
-         <secondary>hypothetical</secondary>
-        </indexterm>
-        <function>rank</function> ( <replaceable>args</replaceable> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <replaceable>sorted_args</replaceable> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Computes the rank of the hypothetical row, with gaps; that is, the row
-        number of the first row in its peer group.
-       </para></entry>
-       <entry>No</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>dense_rank</primary>
-         <secondary>hypothetical</secondary>
-        </indexterm>
-        <function>dense_rank</function> ( <replaceable>args</replaceable> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <replaceable>sorted_args</replaceable> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Computes the rank of the hypothetical row, without gaps; this function
-        effectively counts peer groups.
-       </para></entry>
-       <entry>No</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>percent_rank</primary>
-         <secondary>hypothetical</secondary>
-        </indexterm>
-        <function>percent_rank</function> ( <replaceable>args</replaceable> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <replaceable>sorted_args</replaceable> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes the relative rank of the hypothetical row, that is
-        (<function>rank</function> - 1) / (total rows - 1).
-        The value thus ranges from 0 to 1 inclusive.
-       </para></entry>
-       <entry>No</entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>cume_dist</primary>
-         <secondary>hypothetical</secondary>
-        </indexterm>
-        <function>cume_dist</function> ( <replaceable>args</replaceable> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <replaceable>sorted_args</replaceable> )
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Computes the cumulative distribution, that is (number of rows
-        preceding or peers with hypothetical row) / (total rows).  The value
-        thus ranges from 1/<parameter>N</parameter> to 1.
-       </para></entry>
-       <entry>No</entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <table id="functions-grouping-table">
-   <title>Grouping Operations</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>GROUPING</primary>
-        </indexterm>
-        <function>GROUPING</function> ( <replaceable>group_by_expression(s)</replaceable> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns a bit mask indicating which <literal>GROUP BY</literal>
-        expressions are not included in the current grouping set.
-        Bits are assigned with the rightmost argument corresponding to the
-        least-significant bit; each bit is 0 if the corresponding expression
-        is included in the grouping criteria of the grouping set generating
-        the current result row, and 1 if it is not included.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    The grouping operations shown in
-    <xref linkend="functions-grouping-table"/> are used in conjunction with
-    grouping sets (see <xref linkend="queries-grouping-sets"/>) to distinguish
-    result rows.  The arguments to the <literal>GROUPING</literal> function
-    are not actually evaluated, but they must exactly match expressions given
-    in the <literal>GROUP BY</literal> clause of the associated query level.
-    For example:
-<screen>
-<prompt>=&gt;</prompt> <userinput>SELECT * FROM items_sold;</userinput>
- make  | model | sales
--------+-------+-------
- Foo   | GT    |  10
- Foo   | Tour  |  20
- Bar   | City  |  15
- Bar   | Sport |  5
-(4 rows)
-
-<prompt>=&gt;</prompt> <userinput>SELECT make, model, GROUPING(make,model), sum(sales) FROM items_sold GROUP BY ROLLUP(make,model);</userinput>
- make  | model | grouping | sum
--------+-------+----------+-----
- Foo   | GT    |        0 | 10
- Foo   | Tour  |        0 | 20
- Bar   | City  |        0 | 15
- Bar   | Sport |        0 | 5
- Foo   |       |        1 | 30
- Bar   |       |        1 | 20
-       |       |        3 | 50
-(7 rows)
-</screen>
-    Here, the <literal>grouping</literal> value <literal>0</literal> in the
-    first four rows shows that those have been grouped normally, over both the
-    grouping columns.  The value <literal>1</literal> indicates
-    that <literal>model</literal> was not grouped by in the next-to-last two
-    rows, and the value <literal>3</literal> indicates that
-    neither <literal>make</literal> nor <literal>model</literal> was grouped
-    by in the last row (which therefore is an aggregate over all the input
-    rows).
-   </para>
-
- </sect1>
-
- <sect1 id="functions-window">
-  <title>Window Functions</title>
-
-  <indexterm zone="functions-window">
-   <primary>window function</primary>
-   <secondary>built-in</secondary>
-  </indexterm>
-
-  <para>
-   <firstterm>Window functions</firstterm> provide the ability to perform
-   calculations across sets of rows that are related to the current query
-   row.  See <xref linkend="tutorial-window"/> for an introduction to this
-   feature, and <xref linkend="syntax-window-functions"/> for syntax
-   details.
-  </para>
-
-  <para>
-   The built-in window functions are listed in
-   <xref linkend="functions-window-table"/>.  Note that these functions
-   <emphasis>must</emphasis> be invoked using window function syntax, i.e., an
-   <literal>OVER</literal> clause is required.
-  </para>
-
-  <para>
-   In addition to these functions, any built-in or user-defined
-   ordinary aggregate (i.e., not ordered-set or hypothetical-set aggregates)
-   can be used as a window function; see
-   <xref linkend="functions-aggregate"/> for a list of the built-in aggregates.
-   Aggregate functions act as window functions only when an <literal>OVER</literal>
-   clause follows the call; otherwise they act as plain aggregates
-   and return a single row for the entire set.
-  </para>
-
-   <table id="functions-window-table">
-    <title>General-Purpose Window Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>row_number</primary>
-        </indexterm>
-        <function>row_number</function> ()
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Returns the number of the current row within its partition, counting
-        from 1.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>rank</primary>
-        </indexterm>
-        <function>rank</function> ()
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Returns the rank of the current row, with gaps; that is,
-        the <function>row_number</function> of the first row in its peer
-        group.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>dense_rank</primary>
-        </indexterm>
-        <function>dense_rank</function> ()
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Returns the rank of the current row, without gaps; this function
-        effectively counts peer groups.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>percent_rank</primary>
-        </indexterm>
-        <function>percent_rank</function> ()
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Returns the relative rank of the current row, that is
-        (<function>rank</function> - 1) / (total partition rows - 1).
-        The value thus ranges from 0 to 1 inclusive.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>cume_dist</primary>
-        </indexterm>
-        <function>cume_dist</function> ()
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Returns the cumulative distribution, that is (number of partition rows
-        preceding or peers with current row) / (total partition rows).
-        The value thus ranges from 1/<parameter>N</parameter> to 1.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>ntile</primary>
-        </indexterm>
-        <function>ntile</function> ( <parameter>num_buckets</parameter> <type>integer</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns an integer ranging from 1 to the argument value, dividing the
-        partition as equally as possible.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>lag</primary>
-        </indexterm>
-        <function>lag</function> ( <parameter>value</parameter> <type>anycompatible</type>
-          <optional>, <parameter>offset</parameter> <type>integer</type>
-          <optional>, <parameter>default</parameter> <type>anycompatible</type> </optional></optional> )
-        <returnvalue>anycompatible</returnvalue>
-       </para>
-       <para>
-        Returns <parameter>value</parameter> evaluated at
-        the row that is <parameter>offset</parameter>
-        rows before the current row within the partition; if there is no such
-        row, instead returns <parameter>default</parameter>
-        (which must be of a type compatible with
-        <parameter>value</parameter>).
-        Both <parameter>offset</parameter> and
-        <parameter>default</parameter> are evaluated
-        with respect to the current row.  If omitted,
-        <parameter>offset</parameter> defaults to 1 and
-        <parameter>default</parameter> to <literal>NULL</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>lead</primary>
-        </indexterm>
-        <function>lead</function> ( <parameter>value</parameter> <type>anycompatible</type>
-          <optional>, <parameter>offset</parameter> <type>integer</type>
-          <optional>, <parameter>default</parameter> <type>anycompatible</type> </optional></optional> )
-        <returnvalue>anycompatible</returnvalue>
-       </para>
-       <para>
-        Returns <parameter>value</parameter> evaluated at
-        the row that is <parameter>offset</parameter>
-        rows after the current row within the partition; if there is no such
-        row, instead returns <parameter>default</parameter>
-        (which must be of a type compatible with
-        <parameter>value</parameter>).
-        Both <parameter>offset</parameter> and
-        <parameter>default</parameter> are evaluated
-        with respect to the current row.  If omitted,
-        <parameter>offset</parameter> defaults to 1 and
-        <parameter>default</parameter> to <literal>NULL</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>first_value</primary>
-        </indexterm>
-        <function>first_value</function> ( <parameter>value</parameter> <type>anyelement</type> )
-        <returnvalue>anyelement</returnvalue>
-       </para>
-       <para>
-        Returns <parameter>value</parameter> evaluated
-        at the row that is the first row of the window frame.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>last_value</primary>
-        </indexterm>
-        <function>last_value</function> ( <parameter>value</parameter> <type>anyelement</type> )
-        <returnvalue>anyelement</returnvalue>
-       </para>
-       <para>
-        Returns <parameter>value</parameter> evaluated
-        at the row that is the last row of the window frame.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>nth_value</primary>
-        </indexterm>
-        <function>nth_value</function> ( <parameter>value</parameter> <type>anyelement</type>, <parameter>n</parameter> <type>integer</type> )
-        <returnvalue>anyelement</returnvalue>
-       </para>
-       <para>
-        Returns <parameter>value</parameter> evaluated
-        at the row that is the <parameter>n</parameter>'th
-        row of the window frame (counting from 1);
-        returns <literal>NULL</literal> if there is no such row.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <para>
-   All of the functions listed in
-   <xref linkend="functions-window-table"/> depend on the sort ordering
-   specified by the <literal>ORDER BY</literal> clause of the associated window
-   definition.  Rows that are not distinct when considering only the
-   <literal>ORDER BY</literal> columns are said to be <firstterm>peers</firstterm>.
-   The four ranking functions (including <function>cume_dist</function>) are
-   defined so that they give the same answer for all rows of a peer group.
-  </para>
-
-  <para>
-   Note that <function>first_value</function>, <function>last_value</function>, and
-   <function>nth_value</function> consider only the rows within the <quote>window
-   frame</quote>, which by default contains the rows from the start of the
-   partition through the last peer of the current row.  This is
-   likely to give unhelpful results for <function>last_value</function> and
-   sometimes also <function>nth_value</function>.  You can redefine the frame by
-   adding a suitable frame specification (<literal>RANGE</literal>,
-   <literal>ROWS</literal> or <literal>GROUPS</literal>) to
-   the <literal>OVER</literal> clause.
-   See <xref linkend="syntax-window-functions"/> for more information
-   about frame specifications.
-  </para>
-
-  <para>
-   When an aggregate function is used as a window function, it aggregates
-   over the rows within the current row's window frame.
-   An aggregate used with <literal>ORDER BY</literal> and the default window frame
-   definition produces a <quote>running sum</quote> type of behavior, which may or
-   may not be what's wanted.  To obtain
-   aggregation over the whole partition, omit <literal>ORDER BY</literal> or use
-   <literal>ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING</literal>.
-   Other frame specifications can be used to obtain other effects.
-  </para>
-
-  <note>
-   <para>
-    The SQL standard defines a <literal>RESPECT NULLS</literal> or
-    <literal>IGNORE NULLS</literal> option for <function>lead</function>, <function>lag</function>,
-    <function>first_value</function>, <function>last_value</function>, and
-    <function>nth_value</function>.  This is not implemented in
-    <productname>PostgreSQL</productname>: the behavior is always the
-    same as the standard's default, namely <literal>RESPECT NULLS</literal>.
-    Likewise, the standard's <literal>FROM FIRST</literal> or <literal>FROM LAST</literal>
-    option for <function>nth_value</function> is not implemented: only the
-    default <literal>FROM FIRST</literal> behavior is supported.  (You can achieve
-    the result of <literal>FROM LAST</literal> by reversing the <literal>ORDER BY</literal>
-    ordering.)
-   </para>
-  </note>
-
- </sect1>
-
- <sect1 id="functions-merge-support">
-  <title>Merge Support Functions</title>
-
-  <indexterm>
-   <primary>MERGE</primary>
-   <secondary>RETURNING</secondary>
-  </indexterm>
-
-  <para>
-   <productname>PostgreSQL</productname> includes one merge support function
-   that may be used in the <literal>RETURNING</literal> list of a
-   <xref linkend="sql-merge"/> command to identify the action taken for each
-   row; see <xref linkend="functions-merge-support-table"/>.
-  </para>
-
-  <table id="functions-merge-support-table">
-   <title>Merge Support Functions</title>
-
-   <tgroup cols="1">
-    <thead>
-     <row>
-      <entry role="func_table_entry"><para role="func_signature">
-       Function
-      </para>
-      <para>
-       Description
-      </para></entry>
-     </row>
-    </thead>
-
-    <tbody>
-     <row>
-      <entry id="merge-action" role="func_table_entry"><para role="func_signature">
-       <indexterm>
-        <primary>merge_action</primary>
-       </indexterm>
-       <function>merge_action</function> ( )
-       <returnvalue>text</returnvalue>
-      </para>
-      <para>
-       Returns the merge action command executed for the current row.  This
-       will be <literal>'INSERT'</literal>, <literal>'UPDATE'</literal>, or
-       <literal>'DELETE'</literal>.
-      </para></entry>
-     </row>
-    </tbody>
-   </tgroup>
-  </table>
-
-  <para>
-   Example:
-<screen><![CDATA[
-MERGE INTO products p
-  USING stock s ON p.product_id = s.product_id
-  WHEN MATCHED AND s.quantity > 0 THEN
-    UPDATE SET in_stock = true, quantity = s.quantity
-  WHEN MATCHED THEN
-    UPDATE SET in_stock = false, quantity = 0
-  WHEN NOT MATCHED THEN
-    INSERT (product_id, in_stock, quantity)
-      VALUES (s.product_id, true, s.quantity)
-  RETURNING merge_action(), p.*;
-
- merge_action | product_id | in_stock | quantity
---------------+------------+----------+----------
- UPDATE       |       1001 | t        |       50
- UPDATE       |       1002 | f        |        0
- INSERT       |       1003 | t        |       10
-]]></screen>
-  </para>
-
-  <para>
-   Note that this function can only be used in the <literal>RETURNING</literal>
-   list of a <command>MERGE</command> command.  It is an error to use it in any
-   other part of a query.
-  </para>
-
- </sect1>
-
- <sect1 id="functions-subquery">
-  <title>Subquery Expressions</title>
-
-  <indexterm>
-   <primary>EXISTS</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>IN</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>NOT IN</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>ANY</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>ALL</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>SOME</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>subquery</primary>
-  </indexterm>
-
-  <para>
-   This section describes the <acronym>SQL</acronym>-compliant subquery
-   expressions available in <productname>PostgreSQL</productname>.
-   All of the expression forms documented in this section return
-   Boolean (true/false) results.
-  </para>
-
-  <sect2 id="functions-subquery-exists">
-   <title><literal>EXISTS</literal></title>
-
-<synopsis>
-EXISTS (<replaceable>subquery</replaceable>)
-</synopsis>
-
-  <para>
-   The argument of <token>EXISTS</token> is an arbitrary <command>SELECT</command> statement,
-   or <firstterm>subquery</firstterm>.  The
-   subquery is evaluated to determine whether it returns any rows.
-   If it returns at least one row, the result of <token>EXISTS</token> is
-   <quote>true</quote>; if the subquery returns no rows, the result of <token>EXISTS</token>
-   is <quote>false</quote>.
-  </para>
-
-  <para>
-   The subquery can refer to variables from the surrounding query,
-   which will act as constants during any one evaluation of the subquery.
-  </para>
-
-  <para>
-   The subquery will generally only be executed long enough to determine
-   whether at least one row is returned, not all the way to completion.
-   It is unwise to write a subquery that has side effects (such as
-   calling sequence functions); whether the side effects occur
-   might be unpredictable.
-  </para>
-
-  <para>
-   Since the result depends only on whether any rows are returned,
-   and not on the contents of those rows, the output list of the
-   subquery is normally unimportant.  A common coding convention is
-   to write all <literal>EXISTS</literal> tests in the form
-   <literal>EXISTS(SELECT 1 WHERE ...)</literal>.  There are exceptions to
-   this rule however, such as subqueries that use <token>INTERSECT</token>.
-  </para>
-
-  <para>
-   This simple example is like an inner join on <literal>col2</literal>, but
-   it produces at most one output row for each <literal>tab1</literal> row,
-   even if there are several matching <literal>tab2</literal> rows:
-<screen>
-SELECT col1
-FROM tab1
-WHERE EXISTS (SELECT 1 FROM tab2 WHERE col2 = tab1.col2);
-</screen>
-  </para>
-  </sect2>
-
-  <sect2 id="functions-subquery-in">
-   <title><literal>IN</literal></title>
-
-<synopsis>
-<replaceable>expression</replaceable> IN (<replaceable>subquery</replaceable>)
-</synopsis>
-
-  <para>
-   The right-hand side is a parenthesized
-   subquery, which must return exactly one column.  The left-hand expression
-   is evaluated and compared to each row of the subquery result.
-   The result of <token>IN</token> is <quote>true</quote> if any equal subquery row is found.
-   The result is <quote>false</quote> if no equal row is found (including the
-   case where the subquery returns no rows).
-  </para>
-
-  <para>
-   Note that if the left-hand expression yields null, or if there are
-   no equal right-hand values and at least one right-hand row yields
-   null, the result of the <token>IN</token> construct will be null, not false.
-   This is in accordance with SQL's normal rules for Boolean combinations
-   of null values.
-  </para>
-
-  <para>
-   As with <token>EXISTS</token>, it's unwise to assume that the subquery will
-   be evaluated completely.
-  </para>
-
-<synopsis>
-<replaceable>row_constructor</replaceable> IN (<replaceable>subquery</replaceable>)
-</synopsis>
-
-  <para>
-   The left-hand side of this form of <token>IN</token> is a row constructor,
-   as described in <xref linkend="sql-syntax-row-constructors"/>.
-   The right-hand side is a parenthesized
-   subquery, which must return exactly as many columns as there are
-   expressions in the left-hand row.  The left-hand expressions are
-   evaluated and compared row-wise to each row of the subquery result.
-   The result of <token>IN</token> is <quote>true</quote> if any equal subquery row is found.
-   The result is <quote>false</quote> if no equal row is found (including the
-   case where the subquery returns no rows).
-  </para>
-
-  <para>
-   As usual, null values in the rows are combined per
-   the normal rules of SQL Boolean expressions.  Two rows are considered
-   equal if all their corresponding members are non-null and equal; the rows
-   are unequal if any corresponding members are non-null and unequal;
-   otherwise the result of that row comparison is unknown (null).
-   If all the per-row results are either unequal or null, with at least one
-   null, then the result of <token>IN</token> is null.
-  </para>
-  </sect2>
-
-  <sect2 id="functions-subquery-notin">
-   <title><literal>NOT IN</literal></title>
-
-<synopsis>
-<replaceable>expression</replaceable> NOT IN (<replaceable>subquery</replaceable>)
-</synopsis>
-
-  <para>
-   The right-hand side is a parenthesized
-   subquery, which must return exactly one column.  The left-hand expression
-   is evaluated and compared to each row of the subquery result.
-   The result of <token>NOT IN</token> is <quote>true</quote> if only unequal subquery rows
-   are found (including the case where the subquery returns no rows).
-   The result is <quote>false</quote> if any equal row is found.
-  </para>
-
-  <para>
-   Note that if the left-hand expression yields null, or if there are
-   no equal right-hand values and at least one right-hand row yields
-   null, the result of the <token>NOT IN</token> construct will be null, not true.
-   This is in accordance with SQL's normal rules for Boolean combinations
-   of null values.
-  </para>
-
-  <para>
-   As with <token>EXISTS</token>, it's unwise to assume that the subquery will
-   be evaluated completely.
-  </para>
-
-<synopsis>
-<replaceable>row_constructor</replaceable> NOT IN (<replaceable>subquery</replaceable>)
-</synopsis>
-
-  <para>
-   The left-hand side of this form of <token>NOT IN</token> is a row constructor,
-   as described in <xref linkend="sql-syntax-row-constructors"/>.
-   The right-hand side is a parenthesized
-   subquery, which must return exactly as many columns as there are
-   expressions in the left-hand row.  The left-hand expressions are
-   evaluated and compared row-wise to each row of the subquery result.
-   The result of <token>NOT IN</token> is <quote>true</quote> if only unequal subquery rows
-   are found (including the case where the subquery returns no rows).
-   The result is <quote>false</quote> if any equal row is found.
-  </para>
-
-  <para>
-   As usual, null values in the rows are combined per
-   the normal rules of SQL Boolean expressions.  Two rows are considered
-   equal if all their corresponding members are non-null and equal; the rows
-   are unequal if any corresponding members are non-null and unequal;
-   otherwise the result of that row comparison is unknown (null).
-   If all the per-row results are either unequal or null, with at least one
-   null, then the result of <token>NOT IN</token> is null.
-  </para>
-  </sect2>
-
-  <sect2 id="functions-subquery-any-some">
-   <title><literal>ANY</literal>/<literal>SOME</literal></title>
-
-<synopsis>
-<replaceable>expression</replaceable> <replaceable>operator</replaceable> ANY (<replaceable>subquery</replaceable>)
-<replaceable>expression</replaceable> <replaceable>operator</replaceable> SOME (<replaceable>subquery</replaceable>)
-</synopsis>
-
-  <para>
-   The right-hand side is a parenthesized
-   subquery, which must return exactly one column.  The left-hand expression
-   is evaluated and compared to each row of the subquery result using the
-   given <replaceable>operator</replaceable>, which must yield a Boolean
-   result.
-   The result of <token>ANY</token> is <quote>true</quote> if any true result is obtained.
-   The result is <quote>false</quote> if no true result is found (including the
-   case where the subquery returns no rows).
-  </para>
-
-  <para>
-   <token>SOME</token> is a synonym for <token>ANY</token>.
-   <token>IN</token> is equivalent to <literal>= ANY</literal>.
-  </para>
-
-  <para>
-   Note that if there are no successes and at least one right-hand row yields
-   null for the operator's result, the result of the <token>ANY</token> construct
-   will be null, not false.
-   This is in accordance with SQL's normal rules for Boolean combinations
-   of null values.
-  </para>
-
-  <para>
-   As with <token>EXISTS</token>, it's unwise to assume that the subquery will
-   be evaluated completely.
-  </para>
-
-<synopsis>
-<replaceable>row_constructor</replaceable> <replaceable>operator</replaceable> ANY (<replaceable>subquery</replaceable>)
-<replaceable>row_constructor</replaceable> <replaceable>operator</replaceable> SOME (<replaceable>subquery</replaceable>)
-</synopsis>
-
-  <para>
-   The left-hand side of this form of <token>ANY</token> is a row constructor,
-   as described in <xref linkend="sql-syntax-row-constructors"/>.
-   The right-hand side is a parenthesized
-   subquery, which must return exactly as many columns as there are
-   expressions in the left-hand row.  The left-hand expressions are
-   evaluated and compared row-wise to each row of the subquery result,
-   using the given <replaceable>operator</replaceable>.
-   The result of <token>ANY</token> is <quote>true</quote> if the comparison
-   returns true for any subquery row.
-   The result is <quote>false</quote> if the comparison returns false for every
-   subquery row (including the case where the subquery returns no
-   rows).
-   The result is NULL if no comparison with a subquery row returns true,
-   and at least one comparison returns NULL.
-  </para>
-
-  <para>
-   See <xref linkend="row-wise-comparison"/> for details about the meaning
-   of a row constructor comparison.
-  </para>
-  </sect2>
-
-  <sect2 id="functions-subquery-all">
-   <title><literal>ALL</literal></title>
-
-<synopsis>
-<replaceable>expression</replaceable> <replaceable>operator</replaceable> ALL (<replaceable>subquery</replaceable>)
-</synopsis>
-
-  <para>
-   The right-hand side is a parenthesized
-   subquery, which must return exactly one column.  The left-hand expression
-   is evaluated and compared to each row of the subquery result using the
-   given <replaceable>operator</replaceable>, which must yield a Boolean
-   result.
-   The result of <token>ALL</token> is <quote>true</quote> if all rows yield true
-   (including the case where the subquery returns no rows).
-   The result is <quote>false</quote> if any false result is found.
-   The result is NULL if no comparison with a subquery row returns false,
-   and at least one comparison returns NULL.
-  </para>
-
-  <para>
-   <token>NOT IN</token> is equivalent to <literal>&lt;&gt; ALL</literal>.
-  </para>
-
-  <para>
-   As with <token>EXISTS</token>, it's unwise to assume that the subquery will
-   be evaluated completely.
-  </para>
-
-<synopsis>
-<replaceable>row_constructor</replaceable> <replaceable>operator</replaceable> ALL (<replaceable>subquery</replaceable>)
-</synopsis>
-
-  <para>
-   The left-hand side of this form of <token>ALL</token> is a row constructor,
-   as described in <xref linkend="sql-syntax-row-constructors"/>.
-   The right-hand side is a parenthesized
-   subquery, which must return exactly as many columns as there are
-   expressions in the left-hand row.  The left-hand expressions are
-   evaluated and compared row-wise to each row of the subquery result,
-   using the given <replaceable>operator</replaceable>.
-   The result of <token>ALL</token> is <quote>true</quote> if the comparison
-   returns true for all subquery rows (including the
-   case where the subquery returns no rows).
-   The result is <quote>false</quote> if the comparison returns false for any
-   subquery row.
-   The result is NULL if no comparison with a subquery row returns false,
-   and at least one comparison returns NULL.
-  </para>
-
-  <para>
-   See <xref linkend="row-wise-comparison"/> for details about the meaning
-   of a row constructor comparison.
-  </para>
-  </sect2>
-
-  <sect2 id="functions-subquery-single-row-comp">
-   <title>Single-Row Comparison</title>
-
-   <indexterm zone="functions-subquery">
-    <primary>comparison</primary>
-    <secondary>subquery result row</secondary>
-   </indexterm>
-
-<synopsis>
-<replaceable>row_constructor</replaceable> <replaceable>operator</replaceable> (<replaceable>subquery</replaceable>)
-</synopsis>
-
-  <para>
-   The left-hand side is a row constructor,
-   as described in <xref linkend="sql-syntax-row-constructors"/>.
-   The right-hand side is a parenthesized subquery, which must return exactly
-   as many columns as there are expressions in the left-hand row. Furthermore,
-   the subquery cannot return more than one row.  (If it returns zero rows,
-   the result is taken to be null.)  The left-hand side is evaluated and
-   compared row-wise to the single subquery result row.
-  </para>
-
-  <para>
-   See <xref linkend="row-wise-comparison"/> for details about the meaning
-   of a row constructor comparison.
-  </para>
-  </sect2>
- </sect1>
-
-
- <sect1 id="functions-comparisons">
-  <title>Row and Array Comparisons</title>
-
-  <indexterm>
-   <primary>IN</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>NOT IN</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>ANY</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>ALL</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>SOME</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>composite type</primary>
-   <secondary>comparison</secondary>
-  </indexterm>
-
-  <indexterm>
-   <primary>row-wise comparison</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>comparison</primary>
-   <secondary>composite type</secondary>
-  </indexterm>
-
-  <indexterm>
-   <primary>comparison</primary>
-   <secondary>row constructor</secondary>
-  </indexterm>
-
-  <indexterm>
-   <primary>IS DISTINCT FROM</primary>
-  </indexterm>
-
-  <indexterm>
-   <primary>IS NOT DISTINCT FROM</primary>
-  </indexterm>
-
-  <para>
-   This section describes several specialized constructs for making
-   multiple comparisons between groups of values.  These forms are
-   syntactically related to the subquery forms of the previous section,
-   but do not involve subqueries.
-   The forms involving array subexpressions are
-   <productname>PostgreSQL</productname> extensions; the rest are
-   <acronym>SQL</acronym>-compliant.
-   All of the expression forms documented in this section return
-   Boolean (true/false) results.
-  </para>
-
-  <sect2 id="functions-comparisons-in-scalar">
-   <title><literal>IN</literal></title>
-
-<synopsis>
-<replaceable>expression</replaceable> IN (<replaceable>value</replaceable> <optional>, ...</optional>)
-</synopsis>
-
-  <para>
-   The right-hand side is a parenthesized list
-   of expressions.  The result is <quote>true</quote> if the left-hand expression's
-   result is equal to any of the right-hand expressions.  This is a shorthand
-   notation for
-
-<synopsis>
-<replaceable>expression</replaceable> = <replaceable>value1</replaceable>
-OR
-<replaceable>expression</replaceable> = <replaceable>value2</replaceable>
-OR
-...
-</synopsis>
-  </para>
-
-  <para>
-   Note that if the left-hand expression yields null, or if there are
-   no equal right-hand values and at least one right-hand expression yields
-   null, the result of the <token>IN</token> construct will be null, not false.
-   This is in accordance with SQL's normal rules for Boolean combinations
-   of null values.
-  </para>
-  </sect2>
-
-  <sect2 id="functions-comparisons-not-in">
-   <title><literal>NOT IN</literal></title>
-
-<synopsis>
-<replaceable>expression</replaceable> NOT IN (<replaceable>value</replaceable> <optional>, ...</optional>)
-</synopsis>
-
-  <para>
-   The right-hand side is a parenthesized list
-   of expressions.  The result is <quote>true</quote> if the left-hand expression's
-   result is unequal to all of the right-hand expressions.  This is a shorthand
-   notation for
-
-<synopsis>
-<replaceable>expression</replaceable> &lt;&gt; <replaceable>value1</replaceable>
-AND
-<replaceable>expression</replaceable> &lt;&gt; <replaceable>value2</replaceable>
-AND
-...
-</synopsis>
-  </para>
-
-  <para>
-   Note that if the left-hand expression yields null, or if there are
-   no equal right-hand values and at least one right-hand expression yields
-   null, the result of the <token>NOT IN</token> construct will be null, not true
-   as one might naively expect.
-   This is in accordance with SQL's normal rules for Boolean combinations
-   of null values.
-  </para>
-
-  <tip>
-  <para>
-   <literal>x NOT IN y</literal> is equivalent to <literal>NOT (x IN y)</literal> in all
-   cases.  However, null values are much more likely to trip up the novice when
-   working with <token>NOT IN</token> than when working with <token>IN</token>.
-   It is best to express your condition positively if possible.
-  </para>
-  </tip>
-  </sect2>
-
-  <sect2 id="functions-comparisons-any-some">
-   <title><literal>ANY</literal>/<literal>SOME</literal> (array)</title>
-
-<synopsis>
-<replaceable>expression</replaceable> <replaceable>operator</replaceable> ANY (<replaceable>array expression</replaceable>)
-<replaceable>expression</replaceable> <replaceable>operator</replaceable> SOME (<replaceable>array expression</replaceable>)
-</synopsis>
-
-  <para>
-   The right-hand side is a parenthesized expression, which must yield an
-   array value.
-   The left-hand expression
-   is evaluated and compared to each element of the array using the
-   given <replaceable>operator</replaceable>, which must yield a Boolean
-   result.
-   The result of <token>ANY</token> is <quote>true</quote> if any true result is obtained.
-   The result is <quote>false</quote> if no true result is found (including the
-   case where the array has zero elements).
-  </para>
-
-  <para>
-   If the array expression yields a null array, the result of
-   <token>ANY</token> will be null.  If the left-hand expression yields null,
-   the result of <token>ANY</token> is ordinarily null (though a non-strict
-   comparison operator could possibly yield a different result).
-   Also, if the right-hand array contains any null elements and no true
-   comparison result is obtained, the result of <token>ANY</token>
-   will be null, not false (again, assuming a strict comparison operator).
-   This is in accordance with SQL's normal rules for Boolean combinations
-   of null values.
-  </para>
-
-  <para>
-   <token>SOME</token> is a synonym for <token>ANY</token>.
-  </para>
-  </sect2>
-
-  <sect2 id="functions-comparisons-all">
-   <title><literal>ALL</literal> (array)</title>
-
-<synopsis>
-<replaceable>expression</replaceable> <replaceable>operator</replaceable> ALL (<replaceable>array expression</replaceable>)
-</synopsis>
-
-  <para>
-   The right-hand side is a parenthesized expression, which must yield an
-   array value.
-   The left-hand expression
-   is evaluated and compared to each element of the array using the
-   given <replaceable>operator</replaceable>, which must yield a Boolean
-   result.
-   The result of <token>ALL</token> is <quote>true</quote> if all comparisons yield true
-   (including the case where the array has zero elements).
-   The result is <quote>false</quote> if any false result is found.
-  </para>
-
-  <para>
-   If the array expression yields a null array, the result of
-   <token>ALL</token> will be null.  If the left-hand expression yields null,
-   the result of <token>ALL</token> is ordinarily null (though a non-strict
-   comparison operator could possibly yield a different result).
-   Also, if the right-hand array contains any null elements and no false
-   comparison result is obtained, the result of <token>ALL</token>
-   will be null, not true (again, assuming a strict comparison operator).
-   This is in accordance with SQL's normal rules for Boolean combinations
-   of null values.
-  </para>
-  </sect2>
-
-  <sect2 id="row-wise-comparison">
-   <title>Row Constructor Comparison</title>
-
-<synopsis>
-<replaceable>row_constructor</replaceable> <replaceable>operator</replaceable> <replaceable>row_constructor</replaceable>
-</synopsis>
-
-  <para>
-   Each side is a row constructor,
-   as described in <xref linkend="sql-syntax-row-constructors"/>.
-   The two row constructors must have the same number of fields.
-   The given <replaceable>operator</replaceable> is applied to each pair
-   of corresponding fields.  (Since the fields could be of different
-   types, this means that a different specific operator could be selected
-   for each pair.)
-   All the selected operators must be members of some B-tree operator
-   class, or be the negator of an <literal>=</literal> member of a B-tree
-   operator class, meaning that row constructor comparison is only
-   possible when the <replaceable>operator</replaceable> is
-   <literal>=</literal>,
-   <literal>&lt;&gt;</literal>,
-   <literal>&lt;</literal>,
-   <literal>&lt;=</literal>,
-   <literal>&gt;</literal>, or
-   <literal>&gt;=</literal>,
-   or has semantics similar to one of these.
-  </para>
-
-  <para>
-   The <literal>=</literal> and <literal>&lt;&gt;</literal> cases work slightly differently
-   from the others.  Two rows are considered
-   equal if all their corresponding members are non-null and equal; the rows
-   are unequal if any corresponding members are non-null and unequal;
-   otherwise the result of the row comparison is unknown (null).
-  </para>
-
-  <para>
-   For the <literal>&lt;</literal>, <literal>&lt;=</literal>, <literal>&gt;</literal> and
-   <literal>&gt;=</literal> cases, the row elements are compared left-to-right,
-   stopping as soon as an unequal or null pair of elements is found.
-   If either of this pair of elements is null, the result of the
-   row comparison is unknown (null); otherwise comparison of this pair
-   of elements determines the result.  For example,
-   <literal>ROW(1,2,NULL) &lt; ROW(1,3,0)</literal>
-   yields true, not null, because the third pair of elements are not
-   considered.
-  </para>
-
-<synopsis>
-<replaceable>row_constructor</replaceable> IS DISTINCT FROM <replaceable>row_constructor</replaceable>
-</synopsis>
-
-  <para>
-   This construct is similar to a <literal>&lt;&gt;</literal> row comparison,
-   but it does not yield null for null inputs.  Instead, any null value is
-   considered unequal to (distinct from) any non-null value, and any two
-   nulls are considered equal (not distinct).  Thus the result will
-   either be true or false, never null.
-  </para>
-
-<synopsis>
-<replaceable>row_constructor</replaceable> IS NOT DISTINCT FROM <replaceable>row_constructor</replaceable>
-</synopsis>
-
-  <para>
-   This construct is similar to a <literal>=</literal> row comparison,
-   but it does not yield null for null inputs.  Instead, any null value is
-   considered unequal to (distinct from) any non-null value, and any two
-   nulls are considered equal (not distinct).  Thus the result will always
-   be either true or false, never null.
-  </para>
-
-  </sect2>
-
-  <sect2 id="composite-type-comparison">
-   <title>Composite Type Comparison</title>
-
-<synopsis>
-<replaceable>record</replaceable> <replaceable>operator</replaceable> <replaceable>record</replaceable>
-</synopsis>
-
-  <para>
-   The SQL specification requires row-wise comparison to return NULL if the
-   result depends on comparing two NULL values or a NULL and a non-NULL.
-   <productname>PostgreSQL</productname> does this only when comparing the
-   results of two row constructors (as in
-   <xref linkend="row-wise-comparison"/>) or comparing a row constructor
-   to the output of a subquery (as in <xref linkend="functions-subquery"/>).
-   In other contexts where two composite-type values are compared, two
-   NULL field values are considered equal, and a NULL is considered larger
-   than a non-NULL.  This is necessary in order to have consistent sorting
-   and indexing behavior for composite types.
-  </para>
-
-  <para>
-   Each side is evaluated and they are compared row-wise.  Composite type
-   comparisons are allowed when the <replaceable>operator</replaceable> is
-   <literal>=</literal>,
-   <literal>&lt;&gt;</literal>,
-   <literal>&lt;</literal>,
-   <literal>&lt;=</literal>,
-   <literal>&gt;</literal> or
-   <literal>&gt;=</literal>,
-   or has semantics similar to one of these.  (To be specific, an operator
-   can be a row comparison operator if it is a member of a B-tree operator
-   class, or is the negator of the <literal>=</literal> member of a B-tree operator
-   class.)  The default behavior of the above operators is the same as for
-   <literal>IS [ NOT ] DISTINCT FROM</literal> for row constructors (see
-   <xref linkend="row-wise-comparison"/>).
-  </para>
-
-  <para>
-   To support matching of rows which include elements without a default
-   B-tree operator class, the following operators are defined for composite
-   type comparison:
-   <literal>*=</literal>,
-   <literal>*&lt;&gt;</literal>,
-   <literal>*&lt;</literal>,
-   <literal>*&lt;=</literal>,
-   <literal>*&gt;</literal>, and
-   <literal>*&gt;=</literal>.
-   These operators compare the internal binary representation of the two
-   rows.  Two rows might have a different binary representation even
-   though comparisons of the two rows with the equality operator is true.
-   The ordering of rows under these comparison operators is deterministic
-   but not otherwise meaningful.  These operators are used internally
-   for materialized views and might be useful for other specialized
-   purposes such as replication and B-Tree deduplication (see <xref
-   linkend="btree-deduplication"/>).  They are not intended to be
-   generally useful for writing queries, though.
-  </para>
-  </sect2>
- </sect1>
-
- <sect1 id="functions-srf">
-  <title>Set Returning Functions</title>
-
-  <indexterm zone="functions-srf">
-   <primary>set returning functions</primary>
-   <secondary>functions</secondary>
-  </indexterm>
-
-  <para>
-   This section describes functions that possibly return more than one row.
-   The most widely used functions in this class are series generating
-   functions, as detailed in <xref linkend="functions-srf-series"/> and
-   <xref linkend="functions-srf-subscripts"/>.  Other, more specialized
-   set-returning functions are described elsewhere in this manual.
-   See <xref linkend="queries-tablefunctions"/> for ways to combine multiple
-   set-returning functions.
-  </para>
-
-   <table id="functions-srf-series">
-    <title>Series Generating Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>generate_series</primary>
-        </indexterm>
-        <function>generate_series</function> ( <parameter>start</parameter> <type>integer</type>, <parameter>stop</parameter> <type>integer</type> <optional>, <parameter>step</parameter> <type>integer</type> </optional> )
-        <returnvalue>setof integer</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>generate_series</function> ( <parameter>start</parameter> <type>bigint</type>, <parameter>stop</parameter> <type>bigint</type> <optional>, <parameter>step</parameter> <type>bigint</type> </optional> )
-        <returnvalue>setof bigint</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>generate_series</function> ( <parameter>start</parameter> <type>numeric</type>, <parameter>stop</parameter> <type>numeric</type> <optional>, <parameter>step</parameter> <type>numeric</type> </optional> )
-        <returnvalue>setof numeric</returnvalue>
-       </para>
-       <para>
-        Generates a series of values from <parameter>start</parameter>
-        to <parameter>stop</parameter>, with a step size
-        of <parameter>step</parameter>.  <parameter>step</parameter>
-        defaults to 1.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>generate_series</function> ( <parameter>start</parameter> <type>timestamp</type>, <parameter>stop</parameter> <type>timestamp</type>, <parameter>step</parameter> <type>interval</type> )
-        <returnvalue>setof timestamp</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>generate_series</function> ( <parameter>start</parameter> <type>timestamp with time zone</type>, <parameter>stop</parameter> <type>timestamp with time zone</type>, <parameter>step</parameter> <type>interval</type> <optional>, <parameter>timezone</parameter> <type>text</type> </optional> )
-        <returnvalue>setof timestamp with time zone</returnvalue>
-       </para>
-       <para>
-        Generates a series of values from <parameter>start</parameter>
-        to <parameter>stop</parameter>, with a step size
-        of <parameter>step</parameter>.
-        In the timezone-aware form, times of day and daylight-savings
-        adjustments are computed according to the time zone named by
-        the <parameter>timezone</parameter> argument, or the current
-        <xref linkend="guc-timezone"/> setting if that is omitted.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <para>
-   When <parameter>step</parameter> is positive, zero rows are returned if
-   <parameter>start</parameter> is greater than <parameter>stop</parameter>.
-   Conversely, when <parameter>step</parameter> is negative, zero rows are
-   returned if <parameter>start</parameter> is less than <parameter>stop</parameter>.
-   Zero rows are also returned if any input is <literal>NULL</literal>.
-   It is an error
-   for <parameter>step</parameter> to be zero. Some examples follow:
-<programlisting>
-SELECT * FROM generate_series(2,4);
- generate_series
------------------
-               2
-               3
-               4
-(3 rows)
-
-SELECT * FROM generate_series(5,1,-2);
- generate_series
------------------
-               5
-               3
-               1
-(3 rows)
-
-SELECT * FROM generate_series(4,3);
- generate_series
------------------
-(0 rows)
-
-SELECT generate_series(1.1, 4, 1.3);
- generate_series
------------------
-             1.1
-             2.4
-             3.7
-(3 rows)
-
--- this example relies on the date-plus-integer operator:
-SELECT current_date + s.a AS dates FROM generate_series(0,14,7) AS s(a);
-   dates
-------------
- 2004-02-05
- 2004-02-12
- 2004-02-19
-(3 rows)
-
-SELECT * FROM generate_series('2008-03-01 00:00'::timestamp,
-                              '2008-03-04 12:00', '10 hours');
-   generate_series
----------------------
- 2008-03-01 00:00:00
- 2008-03-01 10:00:00
- 2008-03-01 20:00:00
- 2008-03-02 06:00:00
- 2008-03-02 16:00:00
- 2008-03-03 02:00:00
- 2008-03-03 12:00:00
- 2008-03-03 22:00:00
- 2008-03-04 08:00:00
-(9 rows)
-
--- this example assumes that TimeZone is set to UTC; note the DST transition:
-SELECT * FROM generate_series('2001-10-22 00:00 -04:00'::timestamptz,
-                              '2001-11-01 00:00 -05:00'::timestamptz,
-                              '1 day'::interval, 'America/New_York');
-    generate_series
-------------------------
- 2001-10-22 04:00:00+00
- 2001-10-23 04:00:00+00
- 2001-10-24 04:00:00+00
- 2001-10-25 04:00:00+00
- 2001-10-26 04:00:00+00
- 2001-10-27 04:00:00+00
- 2001-10-28 04:00:00+00
- 2001-10-29 05:00:00+00
- 2001-10-30 05:00:00+00
- 2001-10-31 05:00:00+00
- 2001-11-01 05:00:00+00
-(11 rows)
-</programlisting>
-  </para>
-
-   <table id="functions-srf-subscripts">
-    <title>Subscript Generating Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>generate_subscripts</primary>
-        </indexterm>
-        <function>generate_subscripts</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>dim</parameter> <type>integer</type> )
-        <returnvalue>setof integer</returnvalue>
-       </para>
-       <para>
-        Generates a series comprising the valid subscripts of
-        the <parameter>dim</parameter>'th dimension of the given array.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>generate_subscripts</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>dim</parameter> <type>integer</type>,  <parameter>reverse</parameter> <type>boolean</type> )
-        <returnvalue>setof integer</returnvalue>
-       </para>
-       <para>
-        Generates a series comprising the valid subscripts of
-        the <parameter>dim</parameter>'th dimension of the given array.
-        When <parameter>reverse</parameter> is true, returns the series in
-        reverse order.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <para>
-   <function>generate_subscripts</function> is a convenience function that generates
-   the set of valid subscripts for the specified dimension of the given
-   array.
-   Zero rows are returned for arrays that do not have the requested dimension,
-   or if any input is <literal>NULL</literal>.
-   Some examples follow:
-<programlisting>
--- basic usage:
-SELECT generate_subscripts('{NULL,1,NULL,2}'::int[], 1) AS s;
- s
----
- 1
- 2
- 3
- 4
-(4 rows)
-
--- presenting an array, the subscript and the subscripted
--- value requires a subquery:
-SELECT * FROM arrays;
-         a
---------------------
- {-1,-2}
- {100,200,300}
-(2 rows)
-
-SELECT a AS array, s AS subscript, a[s] AS value
-FROM (SELECT generate_subscripts(a, 1) AS s, a FROM arrays) foo;
-     array     | subscript | value
----------------+-----------+-------
- {-1,-2}       |         1 |    -1
- {-1,-2}       |         2 |    -2
- {100,200,300} |         1 |   100
- {100,200,300} |         2 |   200
- {100,200,300} |         3 |   300
-(5 rows)
-
--- unnest a 2D array:
-CREATE OR REPLACE FUNCTION unnest2(anyarray)
-RETURNS SETOF anyelement AS $$
-select $1[i][j]
-   from generate_subscripts($1,1) g1(i),
-        generate_subscripts($1,2) g2(j);
-$$ LANGUAGE sql IMMUTABLE;
-CREATE FUNCTION
-SELECT * FROM unnest2(ARRAY[[1,2],[3,4]]);
- unnest2
----------
-       1
-       2
-       3
-       4
-(4 rows)
-</programlisting>
-  </para>
-
-  <indexterm>
-   <primary>ordinality</primary>
-  </indexterm>
-
-  <para>
-   When a function in the <literal>FROM</literal> clause is suffixed
-   by <literal>WITH ORDINALITY</literal>, a <type>bigint</type> column is
-   appended to the function's output column(s), which starts from 1 and
-   increments by 1 for each row of the function's output.
-   This is most useful in the case of set returning
-   functions such as <function>unnest()</function>.
-
-<programlisting>
--- set returning function WITH ORDINALITY:
-SELECT * FROM pg_ls_dir('.') WITH ORDINALITY AS t(ls,n);
-       ls        | n
------------------+----
- pg_serial       |  1
- pg_twophase     |  2
- postmaster.opts |  3
- pg_notify       |  4
- postgresql.conf |  5
- pg_tblspc       |  6
- logfile         |  7
- base            |  8
- postmaster.pid  |  9
- pg_ident.conf   | 10
- global          | 11
- pg_xact         | 12
- pg_snapshots    | 13
- pg_multixact    | 14
- PG_VERSION      | 15
- pg_wal          | 16
- pg_hba.conf     | 17
- pg_stat_tmp     | 18
- pg_subtrans     | 19
-(19 rows)
-</programlisting>
-  </para>
-
- </sect1>
-
- <sect1 id="functions-info">
-  <title>System Information Functions and Operators</title>
-
-   <para>
-    The functions described in this section are used to obtain various
-    information about a <productname>PostgreSQL</productname> installation.
-   </para>
-
-  <sect2 id="functions-info-session">
-   <title>Session Information Functions</title>
-
-  <para>
-   <xref linkend="functions-info-session-table"/> shows several
-   functions that extract session and system information.
-  </para>
-
-  <para>
-   In addition to the functions listed in this section, there are a number of
-   functions related to the statistics system that also provide system
-   information. See <xref linkend="monitoring-stats-functions"/> for more
-   information.
-  </para>
-
-   <table id="functions-info-session-table">
-    <title>Session Information Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>current_catalog</primary>
-        </indexterm>
-        <function>current_catalog</function>
-        <returnvalue>name</returnvalue>
-       </para>
-       <para role="func_signature">
-        <indexterm>
-         <primary>current_database</primary>
-        </indexterm>
-        <function>current_database</function> ()
-        <returnvalue>name</returnvalue>
-       </para>
-       <para>
-        Returns the name of the current database.  (Databases are
-        called <quote>catalogs</quote> in the SQL standard,
-        so <function>current_catalog</function> is the standard's
-        spelling.)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>current_query</primary>
-        </indexterm>
-        <function>current_query</function> ()
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the text of the currently executing query, as submitted
-        by the client (which might contain more than one statement).
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>current_role</primary>
-        </indexterm>
-        <function>current_role</function>
-        <returnvalue>name</returnvalue>
-       </para>
-       <para>
-        This is equivalent to <function>current_user</function>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>current_schema</primary>
-        </indexterm>
-        <indexterm>
-         <primary>schema</primary>
-         <secondary>current</secondary>
-        </indexterm>
-        <function>current_schema</function>
-        <returnvalue>name</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>current_schema</function> ()
-        <returnvalue>name</returnvalue>
-       </para>
-       <para>
-        Returns the name of the schema that is first in the search path (or a
-        null value if the search path is empty).  This is the schema that will
-        be used for any tables or other named objects that are created without
-        specifying a target schema.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>current_schemas</primary>
-        </indexterm>
-        <indexterm>
-         <primary>search path</primary>
-         <secondary>current</secondary>
-        </indexterm>
-        <function>current_schemas</function> ( <parameter>include_implicit</parameter> <type>boolean</type> )
-        <returnvalue>name[]</returnvalue>
-       </para>
-       <para>
-        Returns an array of the names of all schemas presently in the
-        effective search path, in their priority order.  (Items in the current
-        <xref linkend="guc-search-path"/> setting that do not correspond to
-        existing, searchable schemas are omitted.)  If the Boolean argument
-        is <literal>true</literal>, then implicitly-searched system schemas
-        such as <literal>pg_catalog</literal> are included in the result.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>current_user</primary>
-        </indexterm>
-        <indexterm>
-         <primary>user</primary>
-         <secondary>current</secondary>
-        </indexterm>
-        <function>current_user</function>
-        <returnvalue>name</returnvalue>
-       </para>
-       <para>
-        Returns the user name of the current execution context.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>inet_client_addr</primary>
-        </indexterm>
-        <function>inet_client_addr</function> ()
-        <returnvalue>inet</returnvalue>
-       </para>
-       <para>
-        Returns the IP address of the current client,
-        or <literal>NULL</literal> if the current connection is via a
-        Unix-domain socket.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>inet_client_port</primary>
-        </indexterm>
-        <function>inet_client_port</function> ()
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the IP port number of the current client,
-        or <literal>NULL</literal> if the current connection is via a
-        Unix-domain socket.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>inet_server_addr</primary>
-        </indexterm>
-        <function>inet_server_addr</function> ()
-        <returnvalue>inet</returnvalue>
-       </para>
-       <para>
-        Returns the IP address on which the server accepted the current
-        connection,
-        or <literal>NULL</literal> if the current connection is via a
-        Unix-domain socket.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>inet_server_port</primary>
-        </indexterm>
-        <function>inet_server_port</function> ()
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the IP port number on which the server accepted the current
-        connection,
-        or <literal>NULL</literal> if the current connection is via a
-        Unix-domain socket.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_backend_pid</primary>
-        </indexterm>
-        <function>pg_backend_pid</function> ()
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the process ID of the server process attached to the current
-        session.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_blocking_pids</primary>
-        </indexterm>
-        <function>pg_blocking_pids</function> ( <type>integer</type> )
-        <returnvalue>integer[]</returnvalue>
-       </para>
-       <para>
-        Returns an array of the process ID(s) of the sessions that are
-        blocking the server process with the specified process ID from
-        acquiring a lock, or an empty array if there is no such server process
-        or it is not blocked.
-       </para>
-       <para>
-        One server process blocks another if it either holds a lock that
-        conflicts with the blocked process's lock request (hard block), or is
-        waiting for a lock that would conflict with the blocked process's lock
-        request and is ahead of it in the wait queue (soft block).  When using
-        parallel queries the result always lists client-visible process IDs
-        (that is, <function>pg_backend_pid</function> results) even if the
-        actual lock is held or awaited by a child worker process.  As a result
-        of that, there may be duplicated PIDs in the result.  Also note that
-        when a prepared transaction holds a conflicting lock, it will be
-        represented by a zero process ID.
-       </para>
-       <para>
-        Frequent calls to this function could have some impact on database
-        performance, because it needs exclusive access to the lock manager's
-        shared state for a short time.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_conf_load_time</primary>
-        </indexterm>
-        <function>pg_conf_load_time</function> ()
-        <returnvalue>timestamp with time zone</returnvalue>
-       </para>
-       <para>
-        Returns the time when the server configuration files were last loaded.
-        If the current session was alive at the time, this will be the time
-        when the session itself re-read the configuration files (so the
-        reading will vary a little in different sessions).  Otherwise it is
-        the time when the postmaster process re-read the configuration files.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_current_logfile</primary>
-        </indexterm>
-        <indexterm>
-         <primary>Logging</primary>
-         <secondary>pg_current_logfile function</secondary>
-        </indexterm>
-        <indexterm>
-          <primary>current_logfiles</primary>
-          <secondary>and the pg_current_logfile function</secondary>
-        </indexterm>
-        <indexterm>
-         <primary>Logging</primary>
-         <secondary>current_logfiles file and the pg_current_logfile
-         function</secondary>
-        </indexterm>
-        <function>pg_current_logfile</function> ( <optional> <type>text</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the path name of the log file currently in use by the logging
-        collector.  The path includes the <xref linkend="guc-log-directory"/>
-        directory and the individual log file name.  The result
-        is <literal>NULL</literal> if the logging collector is disabled.
-        When multiple log files exist, each in a different
-        format, <function>pg_current_logfile</function> without an argument
-        returns the path of the file having the first format found in the
-        ordered list: <literal>stderr</literal>,
-        <literal>csvlog</literal>, <literal>jsonlog</literal>.
-        <literal>NULL</literal> is returned if no log file has any of these
-        formats.
-        To request information about a specific log file format, supply
-        either <literal>csvlog</literal>, <literal>jsonlog</literal> or
-        <literal>stderr</literal> as the
-        value of the optional parameter. The result is <literal>NULL</literal>
-        if the log format requested is not configured in
-        <xref linkend="guc-log-destination"/>.
-        The result reflects the contents of
-        the <filename>current_logfiles</filename> file.
-       </para>
-       <para>
-        This function is restricted to superusers and roles with privileges of
-        the <literal>pg_monitor</literal> role by default, but other users can
-        be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_loaded_modules</primary>
-        </indexterm>
-        <function>pg_get_loaded_modules</function> ()
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>module_name</parameter> <type>text</type>,
-        <parameter>version</parameter> <type>text</type>,
-        <parameter>file_name</parameter> <type>text</type> )
-       </para>
-       <para>
-        Returns a list of the loadable modules that are loaded into the
-        current server session.  The <parameter>module_name</parameter>
-        and <parameter>version</parameter> fields are NULL unless the
-        module author supplied values for them using
-        the <literal>PG_MODULE_MAGIC_EXT</literal> macro.
-        The <parameter>file_name</parameter> field gives the file
-        name of the module (shared library).
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_my_temp_schema</primary>
-        </indexterm>
-        <function>pg_my_temp_schema</function> ()
-        <returnvalue>oid</returnvalue>
-       </para>
-       <para>
-        Returns the OID of the current session's temporary schema, or zero if
-        it has none (because it has not created any temporary tables).
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_is_other_temp_schema</primary>
-        </indexterm>
-        <function>pg_is_other_temp_schema</function> ( <type>oid</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Returns true if the given OID is the OID of another session's
-        temporary schema.  (This can be useful, for example, to exclude other
-        sessions' temporary tables from a catalog display.)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_jit_available</primary>
-        </indexterm>
-        <function>pg_jit_available</function> ()
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Returns true if a <acronym>JIT</acronym> compiler extension is
-        available (see <xref linkend="jit"/>) and the
-        <xref linkend="guc-jit"/> configuration parameter is set to
-        <literal>on</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_numa_available</primary>
-        </indexterm>
-        <function>pg_numa_available</function> ()
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Returns true if the server has been compiled with <acronym>NUMA</acronym> support.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_listening_channels</primary>
-        </indexterm>
-        <function>pg_listening_channels</function> ()
-        <returnvalue>setof text</returnvalue>
-       </para>
-       <para>
-        Returns the set of names of asynchronous notification channels that
-        the current session is listening to.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_notification_queue_usage</primary>
-        </indexterm>
-        <function>pg_notification_queue_usage</function> ()
-        <returnvalue>double precision</returnvalue>
-       </para>
-       <para>
-        Returns the fraction (0&ndash;1) of the asynchronous notification
-        queue's maximum size that is currently occupied by notifications that
-        are waiting to be processed.
-        See <xref linkend="sql-listen"/> and <xref linkend="sql-notify"/>
-        for more information.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_postmaster_start_time</primary>
-        </indexterm>
-        <function>pg_postmaster_start_time</function> ()
-        <returnvalue>timestamp with time zone</returnvalue>
-       </para>
-       <para>
-        Returns the time when the server started.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_safe_snapshot_blocking_pids</primary>
-        </indexterm>
-        <function>pg_safe_snapshot_blocking_pids</function> ( <type>integer</type> )
-        <returnvalue>integer[]</returnvalue>
-       </para>
-       <para>
-        Returns an array of the process ID(s) of the sessions that are blocking
-        the server process with the specified process ID from acquiring a safe
-        snapshot, or an empty array if there is no such server process or it
-        is not blocked.
-       </para>
-       <para>
-        A session running a <literal>SERIALIZABLE</literal> transaction blocks
-        a <literal>SERIALIZABLE READ ONLY DEFERRABLE</literal> transaction
-        from acquiring a snapshot until the latter determines that it is safe
-        to avoid taking any predicate locks.  See
-        <xref linkend="xact-serializable"/> for more information about
-        serializable and deferrable transactions.
-       </para>
-       <para>
-        Frequent calls to this function could have some impact on database
-        performance, because it needs access to the predicate lock manager's
-        shared state for a short time.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_trigger_depth</primary>
-        </indexterm>
-        <function>pg_trigger_depth</function> ()
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the current nesting level
-        of <productname>PostgreSQL</productname> triggers (0 if not called,
-        directly or indirectly, from inside a trigger).
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>session_user</primary>
-        </indexterm>
-        <function>session_user</function>
-        <returnvalue>name</returnvalue>
-       </para>
-       <para>
-        Returns the session user's name.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>system_user</primary>
-        </indexterm>
-        <function>system_user</function>
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the authentication method and the identity (if any) that the
-        user presented during the authentication cycle before they were
-        assigned a database role. It is represented as
-        <literal>auth_method:identity</literal> or
-        <literal>NULL</literal> if the user has not been authenticated (for
-        example if <link linkend="auth-trust">Trust authentication</link> has
-        been used).
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>user</primary>
-        </indexterm>
-        <function>user</function>
-        <returnvalue>name</returnvalue>
-       </para>
-       <para>
-        This is equivalent to <function>current_user</function>.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <note>
-    <para>
-     <function>current_catalog</function>,
-     <function>current_role</function>,
-     <function>current_schema</function>,
-     <function>current_user</function>,
-     <function>session_user</function>,
-     and <function>user</function> have special syntactic status
-     in <acronym>SQL</acronym>: they must be called without trailing
-     parentheses.  In PostgreSQL, parentheses can optionally be used with
-     <function>current_schema</function>, but not with the others.
-    </para>
-   </note>
-
-   <para>
-    The <function>session_user</function> is normally the user who initiated
-    the current database connection; but superusers can change this setting
-    with <xref linkend="sql-set-session-authorization"/>.
-    The <function>current_user</function> is the user identifier
-    that is applicable for permission checking. Normally it is equal
-    to the session user, but it can be changed with
-    <xref linkend="sql-set-role"/>.
-    It also changes during the execution of
-    functions with the attribute <literal>SECURITY DEFINER</literal>.
-    In Unix parlance, the session user is the <quote>real user</quote> and
-    the current user is the <quote>effective user</quote>.
-    <function>current_role</function> and <function>user</function> are
-    synonyms for <function>current_user</function>.  (The SQL standard draws
-    a distinction between <function>current_role</function>
-    and <function>current_user</function>, but <productname>PostgreSQL</productname>
-    does not, since it unifies users and roles into a single kind of entity.)
-   </para>
-
-  </sect2>
-
-  <sect2 id="functions-info-access">
-   <title>Access Privilege Inquiry Functions</title>
-
-  <indexterm>
-   <primary>privilege</primary>
-   <secondary>querying</secondary>
-  </indexterm>
-
-  <para>
-   <xref linkend="functions-info-access-table"/> lists functions that
-   allow querying object access privileges programmatically.
-   (See <xref linkend="ddl-priv"/> for more information about
-   privileges.)
-   In these functions, the user whose privileges are being inquired about
-   can be specified by name or by OID
-   (<structname>pg_authid</structname>.<structfield>oid</structfield>), or if
-   the name is given as <literal>public</literal> then the privileges of the
-   PUBLIC pseudo-role are checked.  Also, the <parameter>user</parameter>
-   argument can be omitted entirely, in which case
-   the <function>current_user</function> is assumed.
-   The object that is being inquired about can be specified either by name or
-   by OID, too.  When specifying by name, a schema name can be included if
-   relevant.
-   The access privilege of interest is specified by a text string, which must
-   evaluate to one of the appropriate privilege keywords for the object's type
-   (e.g., <literal>SELECT</literal>).  Optionally, <literal>WITH GRANT
-   OPTION</literal> can be added to a privilege type to test whether the
-   privilege is held with grant option. Also, multiple privilege types can be
-   listed separated by commas, in which case the result will be true if any of
-   the listed privileges is held. (Case of the privilege string is not
-   significant, and extra whitespace is allowed between but not within
-   privilege names.)
-   Some examples:
-<programlisting>
-SELECT has_table_privilege('myschema.mytable', 'select');
-SELECT has_table_privilege('joe', 'mytable', 'INSERT, SELECT WITH GRANT OPTION');
-</programlisting>
-  </para>
-
-   <table id="functions-info-access-table">
-    <title>Access Privilege Inquiry Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>has_any_column_privilege</primary>
-        </indexterm>
-        <function>has_any_column_privilege</function> (
-          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
-          <parameter>table</parameter> <type>text</type> or <type>oid</type>,
-          <parameter>privilege</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does user have privilege for any column of table?
-        This succeeds either if the privilege is held for the whole table, or
-        if there is a column-level grant of the privilege for at least one
-        column.
-        Allowable privilege types are
-        <literal>SELECT</literal>, <literal>INSERT</literal>,
-        <literal>UPDATE</literal>, and <literal>REFERENCES</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>has_column_privilege</primary>
-        </indexterm>
-        <function>has_column_privilege</function> (
-          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
-          <parameter>table</parameter> <type>text</type> or <type>oid</type>,
-          <parameter>column</parameter> <type>text</type> or <type>smallint</type>,
-          <parameter>privilege</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does user have privilege for the specified table column?
-        This succeeds either if the privilege is held for the whole table, or
-        if there is a column-level grant of the privilege for the column.
-        The column can be specified by name or by attribute number
-        (<structname>pg_attribute</structname>.<structfield>attnum</structfield>).
-        Allowable privilege types are
-        <literal>SELECT</literal>, <literal>INSERT</literal>,
-        <literal>UPDATE</literal>, and <literal>REFERENCES</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>has_database_privilege</primary>
-        </indexterm>
-        <function>has_database_privilege</function> (
-          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
-          <parameter>database</parameter> <type>text</type> or <type>oid</type>,
-          <parameter>privilege</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does user have privilege for database?
-        Allowable privilege types are
-        <literal>CREATE</literal>,
-        <literal>CONNECT</literal>,
-        <literal>TEMPORARY</literal>, and
-        <literal>TEMP</literal> (which is equivalent to
-        <literal>TEMPORARY</literal>).
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>has_foreign_data_wrapper_privilege</primary>
-        </indexterm>
-        <function>has_foreign_data_wrapper_privilege</function> (
-          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
-          <parameter>fdw</parameter> <type>text</type> or <type>oid</type>,
-          <parameter>privilege</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does user have privilege for foreign-data wrapper?
-        The only allowable privilege type is <literal>USAGE</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>has_function_privilege</primary>
-        </indexterm>
-        <function>has_function_privilege</function> (
-          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
-          <parameter>function</parameter> <type>text</type> or <type>oid</type>,
-          <parameter>privilege</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does user have privilege for function?
-        The only allowable privilege type is <literal>EXECUTE</literal>.
-       </para>
-       <para>
-        When specifying a function by name rather than by OID, the allowed
-        input is the same as for the <type>regprocedure</type> data type (see
-        <xref linkend="datatype-oid"/>).
-        An example is:
-<programlisting>
-SELECT has_function_privilege('joeuser', 'myfunc(int, text)', 'execute');
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>has_language_privilege</primary>
-        </indexterm>
-        <function>has_language_privilege</function> (
-          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
-          <parameter>language</parameter> <type>text</type> or <type>oid</type>,
-          <parameter>privilege</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does user have privilege for language?
-        The only allowable privilege type is <literal>USAGE</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>has_largeobject_privilege</primary>
-        </indexterm>
-        <function>has_largeobject_privilege</function> (
-          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
-          <parameter>largeobject</parameter> <type>oid</type>,
-          <parameter>privilege</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does user have privilege for large object?
-        Allowable privilege types are
-        <literal>SELECT</literal> and <literal>UPDATE</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>has_parameter_privilege</primary>
-        </indexterm>
-        <function>has_parameter_privilege</function> (
-          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
-          <parameter>parameter</parameter> <type>text</type>,
-          <parameter>privilege</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does user have privilege for configuration parameter?
-        The parameter name is case-insensitive.
-        Allowable privilege types are <literal>SET</literal>
-        and <literal>ALTER SYSTEM</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>has_schema_privilege</primary>
-        </indexterm>
-        <function>has_schema_privilege</function> (
-          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
-          <parameter>schema</parameter> <type>text</type> or <type>oid</type>,
-          <parameter>privilege</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does user have privilege for schema?
-        Allowable privilege types are
-        <literal>CREATE</literal> and
-        <literal>USAGE</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>has_sequence_privilege</primary>
-        </indexterm>
-        <function>has_sequence_privilege</function> (
-          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
-          <parameter>sequence</parameter> <type>text</type> or <type>oid</type>,
-          <parameter>privilege</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does user have privilege for sequence?
-        Allowable privilege types are
-        <literal>USAGE</literal>,
-        <literal>SELECT</literal>, and
-        <literal>UPDATE</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>has_server_privilege</primary>
-        </indexterm>
-        <function>has_server_privilege</function> (
-          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
-          <parameter>server</parameter> <type>text</type> or <type>oid</type>,
-          <parameter>privilege</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does user have privilege for foreign server?
-        The only allowable privilege type is <literal>USAGE</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>has_table_privilege</primary>
-        </indexterm>
-        <function>has_table_privilege</function> (
-          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
-          <parameter>table</parameter> <type>text</type> or <type>oid</type>,
-          <parameter>privilege</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does user have privilege for table?
-        Allowable privilege types
-        are <literal>SELECT</literal>, <literal>INSERT</literal>,
-        <literal>UPDATE</literal>, <literal>DELETE</literal>,
-        <literal>TRUNCATE</literal>, <literal>REFERENCES</literal>,
-        <literal>TRIGGER</literal>, and <literal>MAINTAIN</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>has_tablespace_privilege</primary>
-        </indexterm>
-        <function>has_tablespace_privilege</function> (
-          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
-          <parameter>tablespace</parameter> <type>text</type> or <type>oid</type>,
-          <parameter>privilege</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does user have privilege for tablespace?
-        The only allowable privilege type is <literal>CREATE</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>has_type_privilege</primary>
-        </indexterm>
-        <function>has_type_privilege</function> (
-          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
-          <parameter>type</parameter> <type>text</type> or <type>oid</type>,
-          <parameter>privilege</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does user have privilege for data type?
-        The only allowable privilege type is <literal>USAGE</literal>.
-        When specifying a type by name rather than by OID, the allowed input
-        is the same as for the <type>regtype</type> data type (see
-        <xref linkend="datatype-oid"/>).
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_has_role</primary>
-        </indexterm>
-        <function>pg_has_role</function> (
-          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
-          <parameter>role</parameter> <type>text</type> or <type>oid</type>,
-          <parameter>privilege</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Does user have privilege for role?
-        Allowable privilege types are
-        <literal>MEMBER</literal>, <literal>USAGE</literal>,
-        and <literal>SET</literal>.
-        <literal>MEMBER</literal> denotes direct or indirect membership in
-        the role without regard to what specific privileges may be conferred.
-        <literal>USAGE</literal> denotes whether the privileges of the role
-        are immediately available without doing <command>SET ROLE</command>,
-        while <literal>SET</literal> denotes whether it is possible to change
-        to the role using the <literal>SET ROLE</literal> command.
-        <literal>WITH ADMIN OPTION</literal> or <literal>WITH GRANT
-        OPTION</literal> can be added to any of these privilege types to
-        test whether the <literal>ADMIN</literal> privilege is held (all
-        six spellings test the same thing).
-        This function does not allow the special case of
-        setting <parameter>user</parameter> to <literal>public</literal>,
-        because the PUBLIC pseudo-role can never be a member of real roles.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>row_security_active</primary>
-        </indexterm>
-        <function>row_security_active</function> (
-          <parameter>table</parameter> <type>text</type> or <type>oid</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is row-level security active for the specified table in the context of
-        the current user and current environment?
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <para>
-   <xref linkend="functions-aclitem-op-table"/> shows the operators
-   available for the <type>aclitem</type> type, which is the catalog
-   representation of access privileges.  See <xref linkend="ddl-priv"/>
-   for information about how to read access privilege values.
-  </para>
-
-    <table id="functions-aclitem-op-table">
-     <title><type>aclitem</type> Operators</title>
-     <tgroup cols="1">
-      <thead>
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         Operator
-        </para>
-        <para>
-         Description
-        </para>
-        <para>
-         Example(s)
-        </para></entry>
-       </row>
-      </thead>
-
-      <tbody>
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>aclitemeq</primary>
-         </indexterm>
-         <type>aclitem</type> <literal>=</literal> <type>aclitem</type>
-         <returnvalue>boolean</returnvalue>
-        </para>
-        <para>
-         Are <type>aclitem</type>s equal?  (Notice that
-         type <type>aclitem</type> lacks the usual set of comparison
-         operators; it has only equality.  In turn, <type>aclitem</type>
-         arrays can only be compared for equality.)
-        </para>
-        <para>
-         <literal>'calvin=r*w/hobbes'::aclitem = 'calvin=r*w*/hobbes'::aclitem</literal>
-         <returnvalue>f</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <indexterm>
-          <primary>aclcontains</primary>
-         </indexterm>
-         <type>aclitem[]</type> <literal>@&gt;</literal> <type>aclitem</type>
-         <returnvalue>boolean</returnvalue>
-        </para>
-        <para>
-         Does array contain the specified privileges?  (This is true if there
-         is an array entry that matches the <type>aclitem</type>'s grantee and
-         grantor, and has at least the specified set of privileges.)
-        </para>
-        <para>
-         <literal>'{calvin=r*w/hobbes,hobbes=r*w*/postgres}'::aclitem[] @&gt; 'calvin=r*/hobbes'::aclitem</literal>
-         <returnvalue>t</returnvalue>
-        </para></entry>
-       </row>
-
-       <row>
-        <entry role="func_table_entry"><para role="func_signature">
-         <type>aclitem[]</type> <literal>~</literal> <type>aclitem</type>
-         <returnvalue>boolean</returnvalue>
-        </para>
-        <para>
-         This is a deprecated alias for <literal>@&gt;</literal>.
-        </para>
-        <para>
-         <literal>'{calvin=r*w/hobbes,hobbes=r*w*/postgres}'::aclitem[] ~ 'calvin=r*/hobbes'::aclitem</literal>
-         <returnvalue>t</returnvalue>
-        </para></entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </table>
-
-   <para>
-    <xref linkend="functions-aclitem-fn-table"/> shows some additional
-    functions to manage the <type>aclitem</type> type.
-   </para>
-
-   <table id="functions-aclitem-fn-table">
-    <title><type>aclitem</type> Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>acldefault</primary>
-        </indexterm>
-        <function>acldefault</function> (
-          <parameter>type</parameter> <type>"char"</type>,
-          <parameter>ownerId</parameter> <type>oid</type> )
-        <returnvalue>aclitem[]</returnvalue>
-       </para>
-       <para>
-        Constructs an <type>aclitem</type> array holding the default access
-        privileges for an object of type <parameter>type</parameter> belonging
-        to the role with OID <parameter>ownerId</parameter>.  This represents
-        the access privileges that will be assumed when an object's
-        <acronym>ACL</acronym> entry is null. (The default access privileges
-        are described in <xref linkend="ddl-priv"/>.)
-        The <parameter>type</parameter> parameter must be one of
-        'c' for <literal>COLUMN</literal>,
-        'r' for <literal>TABLE</literal> and table-like objects,
-        's' for <literal>SEQUENCE</literal>,
-        'd' for <literal>DATABASE</literal>,
-        'f' for <literal>FUNCTION</literal> or <literal>PROCEDURE</literal>,
-        'l' for <literal>LANGUAGE</literal>,
-        'L' for <literal>LARGE OBJECT</literal>,
-        'n' for <literal>SCHEMA</literal>,
-        'p' for <literal>PARAMETER</literal>,
-        't' for <literal>TABLESPACE</literal>,
-        'F' for <literal>FOREIGN DATA WRAPPER</literal>,
-        'S' for <literal>FOREIGN SERVER</literal>,
-        or
-        'T' for <literal>TYPE</literal> or <literal>DOMAIN</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>aclexplode</primary>
-        </indexterm>
-        <function>aclexplode</function> ( <type>aclitem[]</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>grantor</parameter> <type>oid</type>,
-        <parameter>grantee</parameter> <type>oid</type>,
-        <parameter>privilege_type</parameter> <type>text</type>,
-        <parameter>is_grantable</parameter> <type>boolean</type> )
-       </para>
-       <para>
-        Returns the <type>aclitem</type> array as a set of rows.
-        If the grantee is the pseudo-role PUBLIC, it is represented by zero in
-        the <parameter>grantee</parameter> column.  Each granted privilege is
-        represented as <literal>SELECT</literal>, <literal>INSERT</literal>,
-        etc (see <xref linkend="privilege-abbrevs-table"/> for a full list).
-        Note that each privilege is broken out as a separate row, so
-        only one keyword appears in the <parameter>privilege_type</parameter>
-        column.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>makeaclitem</primary>
-        </indexterm>
-        <function>makeaclitem</function> (
-          <parameter>grantee</parameter> <type>oid</type>,
-          <parameter>grantor</parameter> <type>oid</type>,
-          <parameter>privileges</parameter> <type>text</type>,
-          <parameter>is_grantable</parameter> <type>boolean</type> )
-        <returnvalue>aclitem</returnvalue>
-       </para>
-       <para>
-        Constructs an <type>aclitem</type> with the given properties.
-        <parameter>privileges</parameter> is a comma-separated list of
-        privilege names such as <literal>SELECT</literal>,
-        <literal>INSERT</literal>, etc, all of which are set in the
-        result.  (Case of the privilege string is not significant, and
-        extra whitespace is allowed between but not within privilege
-        names.)
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  </sect2>
-
-  <sect2 id="functions-info-schema">
-   <title>Schema Visibility Inquiry Functions</title>
-
-  <para>
-   <xref linkend="functions-info-schema-table"/> shows functions that
-   determine whether a certain object is <firstterm>visible</firstterm> in the
-   current schema search path.
-   For example, a table is said to be visible if its
-   containing schema is in the search path and no table of the same
-   name appears earlier in the search path.  This is equivalent to the
-   statement that the table can be referenced by name without explicit
-   schema qualification.  Thus, to list the names of all visible tables:
-<programlisting>
-SELECT relname FROM pg_class WHERE pg_table_is_visible(oid);
-</programlisting>
-   For functions and operators, an object in the search path is said to be
-   visible if there is no object of the same name <emphasis>and argument data
-   type(s)</emphasis> earlier in the path.  For operator classes and families,
-   both the name and the associated index access method are considered.
-  </para>
-
-   <indexterm>
-    <primary>search path</primary>
-    <secondary>object visibility</secondary>
-   </indexterm>
-
-   <table id="functions-info-schema-table">
-    <title>Schema Visibility Inquiry Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_collation_is_visible</primary>
-        </indexterm>
-        <function>pg_collation_is_visible</function> ( <parameter>collation</parameter> <type>oid</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is collation visible in search path?
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_conversion_is_visible</primary>
-        </indexterm>
-        <function>pg_conversion_is_visible</function> ( <parameter>conversion</parameter> <type>oid</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is conversion visible in search path?
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_function_is_visible</primary>
-        </indexterm>
-        <function>pg_function_is_visible</function> ( <parameter>function</parameter> <type>oid</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is function visible in search path?
-        (This also works for procedures and aggregates.)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_opclass_is_visible</primary>
-        </indexterm>
-        <function>pg_opclass_is_visible</function> ( <parameter>opclass</parameter> <type>oid</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is operator class visible in search path?
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_operator_is_visible</primary>
-        </indexterm>
-        <function>pg_operator_is_visible</function> ( <parameter>operator</parameter> <type>oid</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is operator visible in search path?
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_opfamily_is_visible</primary>
-        </indexterm>
-        <function>pg_opfamily_is_visible</function> ( <parameter>opclass</parameter> <type>oid</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is operator family visible in search path?
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_statistics_obj_is_visible</primary>
-        </indexterm>
-        <function>pg_statistics_obj_is_visible</function> ( <parameter>stat</parameter> <type>oid</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is statistics object visible in search path?
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_table_is_visible</primary>
-        </indexterm>
-        <function>pg_table_is_visible</function> ( <parameter>table</parameter> <type>oid</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is table visible in search path?
-        (This works for all types of relations, including views, materialized
-        views, indexes, sequences and foreign tables.)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_ts_config_is_visible</primary>
-        </indexterm>
-        <function>pg_ts_config_is_visible</function> ( <parameter>config</parameter> <type>oid</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is text search configuration visible in search path?
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_ts_dict_is_visible</primary>
-        </indexterm>
-        <function>pg_ts_dict_is_visible</function> ( <parameter>dict</parameter> <type>oid</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is text search dictionary visible in search path?
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_ts_parser_is_visible</primary>
-        </indexterm>
-        <function>pg_ts_parser_is_visible</function> ( <parameter>parser</parameter> <type>oid</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is text search parser visible in search path?
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_ts_template_is_visible</primary>
-        </indexterm>
-        <function>pg_ts_template_is_visible</function> ( <parameter>template</parameter> <type>oid</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is text search template visible in search path?
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_type_is_visible</primary>
-        </indexterm>
-        <function>pg_type_is_visible</function> ( <parameter>type</parameter> <type>oid</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is type (or domain) visible in search path?
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    All these functions require object OIDs to identify the object to be
-    checked.  If you want to test an object by name, it is convenient to use
-    the OID alias types (<type>regclass</type>, <type>regtype</type>,
-    <type>regprocedure</type>, <type>regoperator</type>, <type>regconfig</type>,
-    or <type>regdictionary</type>),
-    for example:
-<programlisting>
-SELECT pg_type_is_visible('myschema.widget'::regtype);
-</programlisting>
-    Note that it would not make much sense to test a non-schema-qualified
-    type name in this way &mdash; if the name can be recognized at all, it must be visible.
-   </para>
-
-  </sect2>
-
-  <sect2 id="functions-info-catalog">
-   <title>System Catalog Information Functions</title>
-
-  <para>
-   <xref linkend="functions-info-catalog-table"/> lists functions that
-   extract information from the system catalogs.
-  </para>
-
-   <table id="functions-info-catalog-table">
-    <title>System Catalog Information Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry id="format-type" xreflabel="format_type" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>format_type</primary>
-        </indexterm>
-        <function>format_type</function> ( <parameter>type</parameter> <type>oid</type>, <parameter>typemod</parameter> <type>integer</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the SQL name for a data type that is identified by its type
-        OID and possibly a type modifier.  Pass NULL for the type modifier if
-        no specific modifier is known.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_basetype</primary>
-        </indexterm>
-        <function>pg_basetype</function> ( <type>regtype</type> )
-        <returnvalue>regtype</returnvalue>
-       </para>
-       <para>
-        Returns the OID of the base type of a domain identified by its
-        type OID.  If the argument is the OID of a non-domain type,
-        returns the argument as-is.  Returns NULL if the argument is
-        not a valid type OID.  If there's a chain of domain dependencies,
-        it will recurse until finding the base type.
-       </para>
-       <para>
-        Assuming <literal>CREATE DOMAIN mytext AS text</literal>:
-       </para>
-       <para>
-        <literal>pg_basetype('mytext'::regtype)</literal>
-        <returnvalue>text</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="pg-char-to-encoding" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_char_to_encoding</primary>
-        </indexterm>
-        <function>pg_char_to_encoding</function> ( <parameter>encoding</parameter> <type>name</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Converts the supplied encoding name into an integer representing the
-        internal identifier used in some system catalog tables.
-        Returns <literal>-1</literal> if an unknown encoding name is provided.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="pg-encoding-to-char" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_encoding_to_char</primary>
-        </indexterm>
-        <function>pg_encoding_to_char</function> ( <parameter>encoding</parameter> <type>integer</type> )
-        <returnvalue>name</returnvalue>
-       </para>
-       <para>
-        Converts the integer used as the internal identifier of an encoding in some
-        system catalog tables into a human-readable string.
-        Returns an empty string if an invalid encoding number is provided.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_catalog_foreign_keys</primary>
-        </indexterm>
-        <function>pg_get_catalog_foreign_keys</function> ()
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>fktable</parameter> <type>regclass</type>,
-          <parameter>fkcols</parameter> <type>text[]</type>,
-          <parameter>pktable</parameter> <type>regclass</type>,
-          <parameter>pkcols</parameter> <type>text[]</type>,
-          <parameter>is_array</parameter> <type>boolean</type>,
-          <parameter>is_opt</parameter> <type>boolean</type> )
-       </para>
-       <para>
-        Returns a set of records describing the foreign key relationships
-        that exist within the <productname>PostgreSQL</productname> system
-        catalogs.
-        The <parameter>fktable</parameter> column contains the name of the
-        referencing catalog, and the <parameter>fkcols</parameter> column
-        contains the name(s) of the referencing column(s).  Similarly,
-        the <parameter>pktable</parameter> column contains the name of the
-        referenced catalog, and the <parameter>pkcols</parameter> column
-        contains the name(s) of the referenced column(s).
-        If <parameter>is_array</parameter> is true, the last referencing
-        column is an array, each of whose elements should match some entry
-        in the referenced catalog.
-        If <parameter>is_opt</parameter> is true, the referencing column(s)
-        are allowed to contain zeroes instead of a valid reference.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_constraintdef</primary>
-        </indexterm>
-        <function>pg_get_constraintdef</function> ( <parameter>constraint</parameter> <type>oid</type> <optional>, <parameter>pretty</parameter> <type>boolean</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Reconstructs the creating command for a constraint.
-        (This is a decompiled reconstruction, not the original text
-        of the command.)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_expr</primary>
-        </indexterm>
-        <function>pg_get_expr</function> ( <parameter>expr</parameter> <type>pg_node_tree</type>, <parameter>relation</parameter> <type>oid</type> <optional>, <parameter>pretty</parameter> <type>boolean</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Decompiles the internal form of an expression stored in the system
-        catalogs, such as the default value for a column.  If the expression
-        might contain Vars, specify the OID of the relation they refer to as
-        the second parameter; if no Vars are expected, passing zero is
-        sufficient.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_functiondef</primary>
-        </indexterm>
-        <function>pg_get_functiondef</function> ( <parameter>func</parameter> <type>oid</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Reconstructs the creating command for a function or procedure.
-        (This is a decompiled reconstruction, not the original text
-        of the command.)
-        The result is a complete <command>CREATE OR REPLACE FUNCTION</command>
-        or <command>CREATE OR REPLACE PROCEDURE</command> statement.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_function_arguments</primary>
-        </indexterm>
-        <function>pg_get_function_arguments</function> ( <parameter>func</parameter> <type>oid</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Reconstructs the argument list of a function or procedure, in the form
-        it would need to appear in within <command>CREATE FUNCTION</command>
-        (including default values).
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_function_identity_arguments</primary>
-        </indexterm>
-        <function>pg_get_function_identity_arguments</function> ( <parameter>func</parameter> <type>oid</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Reconstructs the argument list necessary to identify a function or
-        procedure, in the form it would need to appear in within commands such
-        as <command>ALTER FUNCTION</command>.  This form omits default values.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_function_result</primary>
-        </indexterm>
-        <function>pg_get_function_result</function> ( <parameter>func</parameter> <type>oid</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Reconstructs the <literal>RETURNS</literal> clause of a function, in
-        the form it would need to appear in within <command>CREATE
-        FUNCTION</command>.  Returns <literal>NULL</literal> for a procedure.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_indexdef</primary>
-        </indexterm>
-        <function>pg_get_indexdef</function> ( <parameter>index</parameter> <type>oid</type> <optional>, <parameter>column</parameter> <type>integer</type>, <parameter>pretty</parameter> <type>boolean</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Reconstructs the creating command for an index.
-        (This is a decompiled reconstruction, not the original text
-        of the command.)  If <parameter>column</parameter> is supplied and is
-        not zero, only the definition of that column is reconstructed.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_keywords</primary>
-        </indexterm>
-        <function>pg_get_keywords</function> ()
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>word</parameter> <type>text</type>,
-        <parameter>catcode</parameter> <type>"char"</type>,
-        <parameter>barelabel</parameter> <type>boolean</type>,
-        <parameter>catdesc</parameter> <type>text</type>,
-        <parameter>baredesc</parameter> <type>text</type> )
-       </para>
-       <para>
-        Returns a set of records describing the SQL keywords recognized by the
-        server.  The <parameter>word</parameter> column contains the
-        keyword.  The <parameter>catcode</parameter> column contains a
-        category code: <literal>U</literal> for an unreserved
-        keyword, <literal>C</literal> for a keyword that can be a column
-        name, <literal>T</literal> for a keyword that can be a type or
-        function name, or <literal>R</literal> for a fully reserved keyword.
-        The <parameter>barelabel</parameter> column
-        contains <literal>true</literal> if the keyword can be used as
-        a <quote>bare</quote> column label in <command>SELECT</command> lists,
-        or <literal>false</literal> if it can only be used
-        after <literal>AS</literal>.
-        The <parameter>catdesc</parameter> column contains a
-        possibly-localized string describing the keyword's category.
-        The <parameter>baredesc</parameter> column contains a
-        possibly-localized string describing the keyword's column label status.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_partkeydef</primary>
-        </indexterm>
-        <function>pg_get_partkeydef</function> ( <parameter>table</parameter> <type>oid</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Reconstructs the definition of a partitioned table's partition
-        key, in the form it would have in the <literal>PARTITION
-        BY</literal> clause of <command>CREATE TABLE</command>.
-        (This is a decompiled reconstruction, not the original text
-        of the command.)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_ruledef</primary>
-        </indexterm>
-        <function>pg_get_ruledef</function> ( <parameter>rule</parameter> <type>oid</type> <optional>, <parameter>pretty</parameter> <type>boolean</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Reconstructs the creating command for a rule.
-        (This is a decompiled reconstruction, not the original text
-        of the command.)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_serial_sequence</primary>
-        </indexterm>
-        <function>pg_get_serial_sequence</function> ( <parameter>table</parameter> <type>text</type>, <parameter>column</parameter> <type>text</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the name of the sequence associated with a column,
-        or NULL if no sequence is associated with the column.
-        If the column is an identity column, the associated sequence is the
-        sequence internally created for that column.
-        For columns created using one of the serial types
-        (<type>serial</type>, <type>smallserial</type>, <type>bigserial</type>),
-        it is the sequence created for that serial column definition.
-        In the latter case, the association can be modified or removed
-        with <command>ALTER SEQUENCE OWNED BY</command>.
-        (This function probably should have been
-        called <function>pg_get_owned_sequence</function>; its current name
-        reflects the fact that it has historically been used with serial-type
-        columns.)  The first parameter is a table name with optional
-        schema, and the second parameter is a column name.  Because the first
-        parameter potentially contains both schema and table names, it is
-        parsed per usual SQL rules, meaning it is lower-cased by default.
-        The second parameter, being just a column name, is treated literally
-        and so has its case preserved.  The result is suitably formatted
-        for passing to the sequence functions (see
-        <xref linkend="functions-sequence"/>).
-       </para>
-       <para>
-        A typical use is in reading the current value of the sequence for an
-        identity or serial column, for example:
-<programlisting>
-SELECT currval(pg_get_serial_sequence('sometable', 'id'));
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_statisticsobjdef</primary>
-        </indexterm>
-        <function>pg_get_statisticsobjdef</function> ( <parameter>statobj</parameter> <type>oid</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Reconstructs the creating command for an extended statistics object.
-        (This is a decompiled reconstruction, not the original text
-        of the command.)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_triggerdef</primary>
-        </indexterm>
-<function>pg_get_triggerdef</function> ( <parameter>trigger</parameter> <type>oid</type> <optional>, <parameter>pretty</parameter> <type>boolean</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Reconstructs the creating command for a trigger.
-        (This is a decompiled reconstruction, not the original text
-        of the command.)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_userbyid</primary>
-        </indexterm>
-        <function>pg_get_userbyid</function> ( <parameter>role</parameter> <type>oid</type> )
-        <returnvalue>name</returnvalue>
-       </para>
-       <para>
-        Returns a role's name given its OID.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_viewdef</primary>
-        </indexterm>
-        <function>pg_get_viewdef</function> ( <parameter>view</parameter> <type>oid</type> <optional>, <parameter>pretty</parameter> <type>boolean</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Reconstructs the underlying <command>SELECT</command> command for a
-        view or materialized view.  (This is a decompiled reconstruction, not
-        the original text of the command.)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>pg_get_viewdef</function> ( <parameter>view</parameter> <type>oid</type>, <parameter>wrap_column</parameter> <type>integer</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Reconstructs the underlying <command>SELECT</command> command for a
-        view or materialized view.  (This is a decompiled reconstruction, not
-        the original text of the command.)  In this form of the function,
-        pretty-printing is always enabled, and long lines are wrapped to try
-        to keep them shorter than the specified number of columns.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>pg_get_viewdef</function> ( <parameter>view</parameter> <type>text</type> <optional>, <parameter>pretty</parameter> <type>boolean</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Reconstructs the underlying <command>SELECT</command> command for a
-        view or materialized view, working from a textual name for the view
-        rather than its OID.  (This is deprecated; use the OID variant
-        instead.)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_index_column_has_property</primary>
-        </indexterm>
-        <function>pg_index_column_has_property</function> ( <parameter>index</parameter> <type>regclass</type>, <parameter>column</parameter> <type>integer</type>, <parameter>property</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Tests whether an index column has the named property.
-        Common index column properties are listed in
-        <xref linkend="functions-info-index-column-props"/>.
-        (Note that extension access methods can define additional property
-        names for their indexes.)
-        <literal>NULL</literal> is returned if the property name is not known
-        or does not apply to the particular object, or if the OID or column
-        number does not identify a valid object.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_index_has_property</primary>
-        </indexterm>
-        <function>pg_index_has_property</function> ( <parameter>index</parameter> <type>regclass</type>, <parameter>property</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Tests whether an index has the named property.
-        Common index properties are listed in
-        <xref linkend="functions-info-index-props"/>.
-        (Note that extension access methods can define additional property
-        names for their indexes.)
-        <literal>NULL</literal> is returned if the property name is not known
-        or does not apply to the particular object, or if the OID does not
-        identify a valid object.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_indexam_has_property</primary>
-        </indexterm>
-        <function>pg_indexam_has_property</function> ( <parameter>am</parameter> <type>oid</type>, <parameter>property</parameter> <type>text</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Tests whether an index access method has the named property.
-        Access method properties are listed in
-        <xref linkend="functions-info-indexam-props"/>.
-        <literal>NULL</literal> is returned if the property name is not known
-        or does not apply to the particular object, or if the OID does not
-        identify a valid object.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_options_to_table</primary>
-        </indexterm>
-        <function>pg_options_to_table</function> ( <parameter>options_array</parameter> <type>text[]</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>option_name</parameter> <type>text</type>,
-        <parameter>option_value</parameter> <type>text</type> )
-       </para>
-       <para>
-        Returns the set of storage options represented by a value from
-        <structname>pg_class</structname>.<structfield>reloptions</structfield> or
-        <structname>pg_attribute</structname>.<structfield>attoptions</structfield>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_settings_get_flags</primary>
-        </indexterm>
-        <function>pg_settings_get_flags</function> ( <parameter>guc</parameter> <type>text</type> )
-        <returnvalue>text[]</returnvalue>
-       </para>
-       <para>
-        Returns an array of the flags associated with the given GUC, or
-        <literal>NULL</literal> if it does not exist. The result is
-        an empty array if the GUC exists but there are no flags to show.
-        Only the most useful flags listed in
-        <xref linkend="functions-pg-settings-flags"/> are exposed.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_tablespace_databases</primary>
-        </indexterm>
-        <function>pg_tablespace_databases</function> ( <parameter>tablespace</parameter> <type>oid</type> )
-        <returnvalue>setof oid</returnvalue>
-       </para>
-       <para>
-        Returns the set of OIDs of databases that have objects stored in the
-        specified tablespace.  If this function returns any rows, the
-        tablespace is not empty and cannot be dropped.  To identify the specific
-        objects populating the tablespace, you will need to connect to the
-        database(s) identified by <function>pg_tablespace_databases</function>
-        and query their <structname>pg_class</structname> catalogs.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_tablespace_location</primary>
-        </indexterm>
-        <function>pg_tablespace_location</function> ( <parameter>tablespace</parameter> <type>oid</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the file system path that this tablespace is located in.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_typeof</primary>
-        </indexterm>
-        <function>pg_typeof</function> ( <type>"any"</type> )
-        <returnvalue>regtype</returnvalue>
-       </para>
-       <para>
-        Returns the OID of the data type of the value that is passed to it.
-        This can be helpful for troubleshooting or dynamically constructing
-        SQL queries.  The function is declared as
-        returning <type>regtype</type>, which is an OID alias type (see
-        <xref linkend="datatype-oid"/>); this means that it is the same as an
-        OID for comparison purposes but displays as a type name.
-       </para>
-       <para>
-        <literal>pg_typeof(33)</literal>
-        <returnvalue>integer</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>COLLATION FOR</primary>
-        </indexterm>
-        <function>COLLATION FOR</function> ( <type>"any"</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the name of the collation of the value that is passed to it.
-        The value is quoted and schema-qualified if necessary.  If no
-        collation was derived for the argument expression,
-        then <literal>NULL</literal> is returned.  If the argument is not of a
-        collatable data type, then an error is raised.
-       </para>
-       <para>
-        <literal>collation for ('foo'::text)</literal>
-        <returnvalue>"default"</returnvalue>
-       </para>
-       <para>
-        <literal>collation for ('foo' COLLATE "de_DE")</literal>
-        <returnvalue>"de_DE"</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_regclass</primary>
-        </indexterm>
-        <function>to_regclass</function> ( <type>text</type> )
-        <returnvalue>regclass</returnvalue>
-       </para>
-       <para>
-        Translates a textual relation name to its OID.  A similar result is
-        obtained by casting the string to type <type>regclass</type> (see
-        <xref linkend="datatype-oid"/>); however, this function will return
-        <literal>NULL</literal> rather than throwing an error if the name is
-        not found.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_regcollation</primary>
-        </indexterm>
-        <function>to_regcollation</function> ( <type>text</type> )
-        <returnvalue>regcollation</returnvalue>
-       </para>
-       <para>
-        Translates a textual collation name to its OID.  A similar result is
-        obtained by casting the string to type <type>regcollation</type> (see
-        <xref linkend="datatype-oid"/>); however, this function will return
-        <literal>NULL</literal> rather than throwing an error if the name is
-        not found.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_regnamespace</primary>
-        </indexterm>
-        <function>to_regnamespace</function> ( <type>text</type> )
-        <returnvalue>regnamespace</returnvalue>
-       </para>
-       <para>
-        Translates a textual schema name to its OID.  A similar result is
-        obtained by casting the string to type <type>regnamespace</type> (see
-        <xref linkend="datatype-oid"/>); however, this function will return
-        <literal>NULL</literal> rather than throwing an error if the name is
-        not found.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_regoper</primary>
-        </indexterm>
-        <function>to_regoper</function> ( <type>text</type> )
-        <returnvalue>regoper</returnvalue>
-       </para>
-       <para>
-        Translates a textual operator name to its OID.  A similar result is
-        obtained by casting the string to type <type>regoper</type> (see
-        <xref linkend="datatype-oid"/>); however, this function will return
-        <literal>NULL</literal> rather than throwing an error if the name is
-        not found or is ambiguous.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_regoperator</primary>
-        </indexterm>
-        <function>to_regoperator</function> ( <type>text</type> )
-        <returnvalue>regoperator</returnvalue>
-       </para>
-       <para>
-        Translates a textual operator name (with parameter types) to its OID.  A similar result is
-        obtained by casting the string to type <type>regoperator</type> (see
-        <xref linkend="datatype-oid"/>); however, this function will return
-        <literal>NULL</literal> rather than throwing an error if the name is
-        not found.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_regproc</primary>
-        </indexterm>
-        <function>to_regproc</function> ( <type>text</type> )
-        <returnvalue>regproc</returnvalue>
-       </para>
-       <para>
-        Translates a textual function or procedure name to its OID.  A similar result is
-        obtained by casting the string to type <type>regproc</type> (see
-        <xref linkend="datatype-oid"/>); however, this function will return
-        <literal>NULL</literal> rather than throwing an error if the name is
-        not found or is ambiguous.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_regprocedure</primary>
-        </indexterm>
-        <function>to_regprocedure</function> ( <type>text</type> )
-        <returnvalue>regprocedure</returnvalue>
-       </para>
-       <para>
-        Translates a textual function or procedure name (with argument types) to its OID.  A similar result is
-        obtained by casting the string to type <type>regprocedure</type> (see
-        <xref linkend="datatype-oid"/>); however, this function will return
-        <literal>NULL</literal> rather than throwing an error if the name is
-        not found.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_regrole</primary>
-        </indexterm>
-        <function>to_regrole</function> ( <type>text</type> )
-        <returnvalue>regrole</returnvalue>
-       </para>
-       <para>
-        Translates a textual role name to its OID.  A similar result is
-        obtained by casting the string to type <type>regrole</type> (see
-        <xref linkend="datatype-oid"/>); however, this function will return
-        <literal>NULL</literal> rather than throwing an error if the name is
-        not found.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="to-regtype" xreflabel="to_regtype" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_regtype</primary>
-        </indexterm>
-        <function>to_regtype</function> ( <type>text</type> )
-        <returnvalue>regtype</returnvalue>
-       </para>
-       <para>
-        Parses a string of text, extracts a potential type name from it,
-        and translates that name into a type OID.  A syntax error in the
-        string will result in an error; but if the string is a
-        syntactically valid type name that happens not to be found in the
-        catalogs, the result is <literal>NULL</literal>.  A similar result
-        is obtained by casting the string to type <type>regtype</type>
-        (see <xref linkend="datatype-oid"/>), except that that will throw
-        error for name not found.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>to_regtypemod</primary>
-        </indexterm>
-        <function>to_regtypemod</function> ( <type>text</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Parses a string of text, extracts a potential type name from it,
-        and translates its type modifier, if any.  A syntax error in the
-        string will result in an error; but if the string is a
-        syntactically valid type name that happens not to be found in the
-        catalogs, the result is <literal>NULL</literal>.  The result is
-        <literal>-1</literal> if no type modifier is present.
-       </para>
-       <para>
-        <function>to_regtypemod</function> can be combined with
-        <xref linkend="to-regtype"/> to produce appropriate inputs for
-        <xref linkend="format-type"/>, allowing a string representing a
-        type name to be canonicalized.
-       </para>
-       <para>
-        <literal>format_type(to_regtype('varchar(32)'), to_regtypemod('varchar(32)'))</literal>
-        <returnvalue>character varying(32)</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  <para>
-   Most of the functions that reconstruct (decompile) database objects
-   have an optional <parameter>pretty</parameter> flag, which
-   if <literal>true</literal> causes the result to
-   be <quote>pretty-printed</quote>.  Pretty-printing suppresses unnecessary
-   parentheses and adds whitespace for legibility.
-   The pretty-printed format is more readable, but the default format
-   is more likely to be interpreted the same way by future versions of
-   <productname>PostgreSQL</productname>; so avoid using pretty-printed output
-   for dump purposes.  Passing <literal>false</literal> for
-   the <parameter>pretty</parameter> parameter yields the same result as
-   omitting the parameter.
-  </para>
-
-  <table id="functions-info-index-column-props">
-   <title>Index Column Properties</title>
-   <tgroup cols="2">
-    <thead>
-     <row><entry>Name</entry><entry>Description</entry></row>
-    </thead>
-    <tbody>
-     <row>
-      <entry><literal>asc</literal></entry>
-      <entry>Does the column sort in ascending order on a forward scan?
-      </entry>
-     </row>
-     <row>
-      <entry><literal>desc</literal></entry>
-      <entry>Does the column sort in descending order on a forward scan?
-      </entry>
-     </row>
-     <row>
-      <entry><literal>nulls_first</literal></entry>
-      <entry>Does the column sort with nulls first on a forward scan?
-      </entry>
-     </row>
-     <row>
-      <entry><literal>nulls_last</literal></entry>
-      <entry>Does the column sort with nulls last on a forward scan?
-      </entry>
-     </row>
-     <row>
-      <entry><literal>orderable</literal></entry>
-      <entry>Does the column possess any defined sort ordering?
-      </entry>
-     </row>
-     <row>
-      <entry><literal>distance_orderable</literal></entry>
-      <entry>Can the column be scanned in order by a <quote>distance</quote>
-      operator, for example <literal>ORDER BY col &lt;-&gt; constant</literal> ?
-      </entry>
-     </row>
-     <row>
-      <entry><literal>returnable</literal></entry>
-      <entry>Can the column value be returned by an index-only scan?
-      </entry>
-     </row>
-     <row>
-      <entry><literal>search_array</literal></entry>
-      <entry>Does the column natively support <literal>col = ANY(array)</literal>
-      searches?
-      </entry>
-     </row>
-     <row>
-      <entry><literal>search_nulls</literal></entry>
-      <entry>Does the column support <literal>IS NULL</literal> and
-      <literal>IS NOT NULL</literal> searches?
-      </entry>
-     </row>
-    </tbody>
-   </tgroup>
-  </table>
-
-  <table id="functions-info-index-props">
-   <title>Index Properties</title>
-   <tgroup cols="2">
-    <thead>
-     <row><entry>Name</entry><entry>Description</entry></row>
-    </thead>
-    <tbody>
-     <row>
-      <entry><literal>clusterable</literal></entry>
-      <entry>Can the index be used in a <literal>CLUSTER</literal> command?
-      </entry>
-     </row>
-     <row>
-      <entry><literal>index_scan</literal></entry>
-      <entry>Does the index support plain (non-bitmap) scans?
-      </entry>
-     </row>
-     <row>
-      <entry><literal>bitmap_scan</literal></entry>
-      <entry>Does the index support bitmap scans?
-      </entry>
-     </row>
-     <row>
-      <entry><literal>backward_scan</literal></entry>
-      <entry>Can the scan direction be changed in mid-scan (to
-             support <literal>FETCH BACKWARD</literal> on a cursor without
-             needing materialization)?
-      </entry>
-     </row>
-    </tbody>
-   </tgroup>
-  </table>
-
-  <table id="functions-info-indexam-props">
-   <title>Index Access Method Properties</title>
-   <tgroup cols="2">
-    <thead>
-     <row><entry>Name</entry><entry>Description</entry></row>
-    </thead>
-    <tbody>
-     <row>
-      <entry><literal>can_order</literal></entry>
-      <entry>Does the access method support <literal>ASC</literal>,
-      <literal>DESC</literal> and related keywords in
-      <literal>CREATE INDEX</literal>?
-      </entry>
-     </row>
-     <row>
-      <entry><literal>can_unique</literal></entry>
-      <entry>Does the access method support unique indexes?
-      </entry>
-     </row>
-     <row>
-      <entry><literal>can_multi_col</literal></entry>
-      <entry>Does the access method support indexes with multiple columns?
-      </entry>
-     </row>
-     <row>
-      <entry><literal>can_exclude</literal></entry>
-      <entry>Does the access method support exclusion constraints?
-      </entry>
-     </row>
-     <row>
-      <entry><literal>can_include</literal></entry>
-      <entry>Does the access method support the <literal>INCLUDE</literal>
-        clause of <literal>CREATE INDEX</literal>?
-      </entry>
-     </row>
-    </tbody>
-   </tgroup>
-  </table>
-
-  <table id="functions-pg-settings-flags">
-   <title>GUC Flags</title>
-   <tgroup cols="2">
-    <thead>
-     <row><entry>Flag</entry><entry>Description</entry></row>
-    </thead>
-    <tbody>
-     <row>
-      <entry><literal>EXPLAIN</literal></entry>
-      <entry>Parameters with this flag are included in
-       <command>EXPLAIN (SETTINGS)</command> commands.
-      </entry>
-     </row>
-     <row>
-      <entry><literal>NO_SHOW_ALL</literal></entry>
-      <entry>Parameters with this flag are excluded from
-       <command>SHOW ALL</command> commands.
-      </entry>
-     </row>
-     <row>
-      <entry><literal>NO_RESET</literal></entry>
-      <entry>Parameters with this flag do not support
-      <command>RESET</command> commands.
-      </entry>
-     </row>
-     <row>
-      <entry><literal>NO_RESET_ALL</literal></entry>
-      <entry>Parameters with this flag are excluded from
-       <command>RESET ALL</command> commands.
-      </entry>
-     </row>
-     <row>
-      <entry><literal>NOT_IN_SAMPLE</literal></entry>
-      <entry>Parameters with this flag are not included in
-       <filename>postgresql.conf</filename> by default.
-      </entry>
-     </row>
-     <row>
-      <entry><literal>RUNTIME_COMPUTED</literal></entry>
-      <entry>Parameters with this flag are runtime-computed ones.
-      </entry>
-     </row>
-    </tbody>
-   </tgroup>
-  </table>
-
-  </sect2>
-
-  <sect2 id="functions-info-object">
-   <title>Object Information and Addressing Functions</title>
-
-  <para>
-   <xref linkend="functions-info-object-table"/> lists functions related to
-   database object identification and addressing.
-  </para>
-
-   <table id="functions-info-object-table">
-    <title>Object Information and Addressing Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_acl</primary>
-        </indexterm>
-        <function>pg_get_acl</function> ( <parameter>classid</parameter> <type>oid</type>, <parameter>objid</parameter> <type>oid</type>, <parameter>objsubid</parameter> <type>integer</type> )
-        <returnvalue>aclitem[]</returnvalue>
-       </para>
-       <para>
-        Returns the <acronym>ACL</acronym> for a database object, specified
-        by catalog OID, object OID and sub-object ID. This function returns
-        <literal>NULL</literal> values for undefined objects.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_describe_object</primary>
-        </indexterm>
-        <function>pg_describe_object</function> ( <parameter>classid</parameter> <type>oid</type>, <parameter>objid</parameter> <type>oid</type>, <parameter>objsubid</parameter> <type>integer</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns a textual description of a database object identified by
-        catalog OID, object OID, and sub-object ID (such as a column number
-        within a table; the sub-object ID is zero when referring to a whole
-        object).  This description is intended to be human-readable, and might
-        be translated, depending on server configuration.  This is especially
-        useful to determine the identity of an object referenced in the
-        <structname>pg_depend</structname> catalog. This function returns
-        <literal>NULL</literal> values for undefined objects.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_identify_object</primary>
-        </indexterm>
-        <function>pg_identify_object</function> ( <parameter>classid</parameter> <type>oid</type>, <parameter>objid</parameter> <type>oid</type>, <parameter>objsubid</parameter> <type>integer</type> )
-        <returnvalue>record</returnvalue>
-        ( <parameter>type</parameter> <type>text</type>,
-        <parameter>schema</parameter> <type>text</type>,
-        <parameter>name</parameter> <type>text</type>,
-        <parameter>identity</parameter> <type>text</type> )
-       </para>
-       <para>
-        Returns a row containing enough information to uniquely identify the
-        database object specified by catalog OID, object OID and sub-object
-        ID.
-        This information is intended to be machine-readable, and is never
-        translated.
-        <parameter>type</parameter> identifies the type of database object;
-        <parameter>schema</parameter> is the schema name that the object
-        belongs in, or <literal>NULL</literal> for object types that do not
-        belong to schemas;
-        <parameter>name</parameter> is the name of the object, quoted if
-        necessary, if the name (along with schema name, if pertinent) is
-        sufficient to uniquely identify the object,
-        otherwise <literal>NULL</literal>;
-        <parameter>identity</parameter> is the complete object identity, with
-        the precise format depending on object type, and each name within the
-        format being schema-qualified and quoted as necessary. Undefined
-        objects are identified with <literal>NULL</literal> values.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_identify_object_as_address</primary>
-        </indexterm>
-        <function>pg_identify_object_as_address</function> ( <parameter>classid</parameter> <type>oid</type>, <parameter>objid</parameter> <type>oid</type>, <parameter>objsubid</parameter> <type>integer</type> )
-        <returnvalue>record</returnvalue>
-        ( <parameter>type</parameter> <type>text</type>,
-        <parameter>object_names</parameter> <type>text[]</type>,
-        <parameter>object_args</parameter> <type>text[]</type> )
-       </para>
-       <para>
-        Returns a row containing enough information to uniquely identify the
-        database object specified by catalog OID, object OID and sub-object
-        ID.
-        The returned information is independent of the current server, that
-        is, it could be used to identify an identically named object in
-        another server.
-        <parameter>type</parameter> identifies the type of database object;
-        <parameter>object_names</parameter> and
-        <parameter>object_args</parameter>
-        are text arrays that together form a reference to the object.
-        These three values can be passed
-        to <function>pg_get_object_address</function> to obtain the internal
-        address of the object.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_object_address</primary>
-        </indexterm>
-        <function>pg_get_object_address</function> ( <parameter>type</parameter> <type>text</type>, <parameter>object_names</parameter> <type>text[]</type>, <parameter>object_args</parameter> <type>text[]</type> )
-        <returnvalue>record</returnvalue>
-        ( <parameter>classid</parameter> <type>oid</type>,
-        <parameter>objid</parameter> <type>oid</type>,
-        <parameter>objsubid</parameter> <type>integer</type> )
-       </para>
-       <para>
-        Returns a row containing enough information to uniquely identify the
-        database object specified by a type code and object name and argument
-        arrays.
-        The returned values are the ones that would be used in system catalogs
-        such as <structname>pg_depend</structname>; they can be passed to
-        other system functions such as <function>pg_describe_object</function>
-        or <function>pg_identify_object</function>.
-        <parameter>classid</parameter> is the OID of the system catalog
-        containing the object;
-        <parameter>objid</parameter> is the OID of the object itself, and
-        <parameter>objsubid</parameter> is the sub-object ID, or zero if none.
-        This function is the inverse
-        of <function>pg_identify_object_as_address</function>.
-        Undefined objects are identified with <literal>NULL</literal> values.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    <function>pg_get_acl</function> is useful for retrieving and inspecting
-    the privileges associated with database objects without looking at
-    specific catalogs. For example, to retrieve all the granted privileges
-    on objects in the current database:
-<programlisting>
-postgres=# SELECT
-    (pg_identify_object(s.classid,s.objid,s.objsubid)).*,
-    pg_catalog.pg_get_acl(s.classid,s.objid,s.objsubid) AS acl
-FROM pg_catalog.pg_shdepend AS s
-JOIN pg_catalog.pg_database AS d
-    ON d.datname = current_database() AND
-       d.oid = s.dbid
-JOIN pg_catalog.pg_authid AS a
-    ON a.oid = s.refobjid AND
-       s.refclassid = 'pg_authid'::regclass
-WHERE s.deptype = 'a';
--[ RECORD 1 ]-----------------------------------------
-type     | table
-schema   | public
-name     | testtab
-identity | public.testtab
-acl      | {postgres=arwdDxtm/postgres,foo=r/postgres}
-</programlisting>
-   </para>
-
-  </sect2>
-
-  <sect2 id="functions-info-comment">
-   <title>Comment Information Functions</title>
-
-   <indexterm>
-    <primary>comment</primary>
-    <secondary sortas="database objects">about database objects</secondary>
-   </indexterm>
-
-   <para>
-    The functions shown in <xref linkend="functions-info-comment-table"/>
-    extract comments previously stored with the <xref linkend="sql-comment"/>
-    command.  A null value is returned if no
-    comment could be found for the specified parameters.
-   </para>
-
-   <table id="functions-info-comment-table">
-    <title>Comment Information Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>col_description</primary>
-        </indexterm>
-        <function>col_description</function> ( <parameter>table</parameter> <type>oid</type>, <parameter>column</parameter> <type>integer</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the comment for a table column, which is specified by the OID
-        of its table and its column number.
-        (<function>obj_description</function> cannot be used for table
-        columns, since columns do not have OIDs of their own.)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>obj_description</primary>
-        </indexterm>
-        <function>obj_description</function> ( <parameter>object</parameter> <type>oid</type>, <parameter>catalog</parameter> <type>name</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the comment for a database object specified by its OID and the
-        name of the containing system catalog.  For
-        example, <literal>obj_description(123456, 'pg_class')</literal> would
-        retrieve the comment for the table with OID 123456.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <function>obj_description</function> ( <parameter>object</parameter> <type>oid</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the comment for a database object specified by its OID alone.
-        This is <emphasis>deprecated</emphasis> since there is no guarantee
-        that OIDs are unique across different system catalogs; therefore, the
-        wrong comment might be returned.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>shobj_description</primary>
-        </indexterm>
-        <function>shobj_description</function> ( <parameter>object</parameter> <type>oid</type>, <parameter>catalog</parameter> <type>name</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the comment for a shared database object specified by its OID
-        and the name of the containing system catalog.  This is just
-        like <function>obj_description</function> except that it is used for
-        retrieving comments on shared objects (that is, databases, roles, and
-        tablespaces).  Some system catalogs are global to all databases within
-        each cluster, and the descriptions for objects in them are stored
-        globally as well.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  </sect2>
-
-  <sect2 id="functions-info-validity">
-   <title>Data Validity Checking Functions</title>
-
-   <para>
-    The functions shown in <xref linkend="functions-info-validity-table"/>
-    can be helpful for checking validity of proposed input data.
-   </para>
-
-   <table id="functions-info-validity-table">
-    <title>Data Validity Checking Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_input_is_valid</primary>
-        </indexterm>
-        <function>pg_input_is_valid</function> (
-          <parameter>string</parameter> <type>text</type>,
-          <parameter>type</parameter> <type>text</type>
-        )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Tests whether the given <parameter>string</parameter> is valid
-        input for the specified data type, returning true or false.
-       </para>
-       <para>
-        This function will only work as desired if the data type's input
-        function has been updated to report invalid input as
-        a <quote>soft</quote> error.  Otherwise, invalid input will abort
-        the transaction, just as if the string had been cast to the type
-        directly.
-        </para>
-        <para>
-         <literal>pg_input_is_valid('42', 'integer')</literal>
-         <returnvalue>t</returnvalue>
-        </para>
-        <para>
-         <literal>pg_input_is_valid('42000000000', 'integer')</literal>
-         <returnvalue>f</returnvalue>
-        </para>
-        <para>
-         <literal>pg_input_is_valid('1234.567', 'numeric(7,4)')</literal>
-         <returnvalue>f</returnvalue>
-       </para></entry>
-      </row>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_input_error_info</primary>
-        </indexterm>
-        <function>pg_input_error_info</function> (
-          <parameter>string</parameter> <type>text</type>,
-          <parameter>type</parameter> <type>text</type>
-        )
-        <returnvalue>record</returnvalue>
-        ( <parameter>message</parameter> <type>text</type>,
-        <parameter>detail</parameter> <type>text</type>,
-        <parameter>hint</parameter> <type>text</type>,
-        <parameter>sql_error_code</parameter> <type>text</type> )
-       </para>
-       <para>
-        Tests whether the given <parameter>string</parameter> is valid
-        input for the specified data type; if not, return the details of
-        the error that would have been thrown.  If the input is valid, the
-        results are NULL.  The inputs are the same as
-        for <function>pg_input_is_valid</function>.
-       </para>
-       <para>
-        This function will only work as desired if the data type's input
-        function has been updated to report invalid input as
-        a <quote>soft</quote> error.  Otherwise, invalid input will abort
-        the transaction, just as if the string had been cast to the type
-        directly.
-       </para>
-       <para>
-        <literal>SELECT * FROM pg_input_error_info('42000000000', 'integer')</literal>
-        <returnvalue></returnvalue>
-<programlisting>
-                       message                        | detail | hint | sql_error_code
-------------------------------------------------------+--------+------+----------------
- value "42000000000" is out of range for type integer |        |      | 22003
-</programlisting>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  </sect2>
-
-  <sect2 id="functions-info-snapshot">
-   <title>Transaction ID and Snapshot Information Functions</title>
-
-   <para>
-    The functions shown in <xref linkend="functions-pg-snapshot"/>
-    provide server transaction information in an exportable form.  The main
-    use of these functions is to determine which transactions were committed
-    between two snapshots.
-   </para>
-
-   <table id="functions-pg-snapshot">
-    <title>Transaction ID and Snapshot Information Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>age</primary>
-        </indexterm>
-        <function>age</function>  ( <type>xid</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the number of transactions between the supplied
-        transaction id and the current transaction counter.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>mxid_age</primary>
-        </indexterm>
-        <function>mxid_age</function>  ( <type>xid</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns the number of multixacts IDs between the supplied
-        multixact ID and the current multixacts counter.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_current_xact_id</primary>
-        </indexterm>
-        <function>pg_current_xact_id</function> ()
-        <returnvalue>xid8</returnvalue>
-       </para>
-       <para>
-        Returns the current transaction's ID.  It will assign a new one if the
-        current transaction does not have one already (because it has not
-        performed any database updates);  see <xref
-        linkend="transaction-id"/> for details.  If executed in a
-        subtransaction, this will return the top-level transaction ID;
-        see <xref linkend="subxacts"/> for details.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_current_xact_id_if_assigned</primary>
-        </indexterm>
-        <function>pg_current_xact_id_if_assigned</function> ()
-        <returnvalue>xid8</returnvalue>
-       </para>
-       <para>
-        Returns the current transaction's ID, or <literal>NULL</literal> if no
-        ID is assigned yet.  (It's best to use this variant if the transaction
-        might otherwise be read-only, to avoid unnecessary consumption of an
-        XID.)
-        If executed in a subtransaction, this will return the top-level
-        transaction ID.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_xact_status</primary>
-        </indexterm>
-        <function>pg_xact_status</function> ( <type>xid8</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Reports the commit status of a recent transaction.
-        The result is one of <literal>in progress</literal>,
-        <literal>committed</literal>, or <literal>aborted</literal>,
-        provided that the transaction is recent enough that the system retains
-        the commit status of that transaction.
-        If it is old enough that no references to the transaction survive in
-        the system and the commit status information has been discarded, the
-        result is <literal>NULL</literal>.
-        Applications might use this function, for example, to determine
-        whether their transaction committed or aborted after the application
-        and database server become disconnected while
-        a <literal>COMMIT</literal> is in progress.
-        Note that prepared transactions are reported as <literal>in
-        progress</literal>; applications must check <link
-        linkend="view-pg-prepared-xacts"><structname>pg_prepared_xacts</structname></link>
-        if they need to determine whether a transaction ID belongs to a
-        prepared transaction.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_current_snapshot</primary>
-        </indexterm>
-        <function>pg_current_snapshot</function> ()
-        <returnvalue>pg_snapshot</returnvalue>
-       </para>
-       <para>
-        Returns a current <firstterm>snapshot</firstterm>, a data structure
-        showing which transaction IDs are now in-progress.
-        Only top-level transaction IDs are included in the snapshot;
-        subtransaction IDs are not shown;  see <xref linkend="subxacts"/>
-        for details.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_snapshot_xip</primary>
-        </indexterm>
-        <function>pg_snapshot_xip</function> ( <type>pg_snapshot</type> )
-        <returnvalue>setof xid8</returnvalue>
-       </para>
-       <para>
-        Returns the set of in-progress transaction IDs contained in a snapshot.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_snapshot_xmax</primary>
-        </indexterm>
-        <function>pg_snapshot_xmax</function> ( <type>pg_snapshot</type> )
-        <returnvalue>xid8</returnvalue>
-       </para>
-       <para>
-        Returns the <structfield>xmax</structfield> of a snapshot.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_snapshot_xmin</primary>
-        </indexterm>
-        <function>pg_snapshot_xmin</function> ( <type>pg_snapshot</type> )
-        <returnvalue>xid8</returnvalue>
-       </para>
-       <para>
-        Returns the <structfield>xmin</structfield> of a snapshot.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_visible_in_snapshot</primary>
-        </indexterm>
-        <function>pg_visible_in_snapshot</function> ( <type>xid8</type>, <type>pg_snapshot</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Is the given transaction ID <firstterm>visible</firstterm> according
-        to this snapshot (that is, was it completed before the snapshot was
-        taken)?  Note that this function will not give the correct answer for
-        a subtransaction ID (subxid);  see <xref linkend="subxacts"/> for
-        details.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    The internal transaction ID type <type>xid</type> is 32 bits wide and
-    wraps around every 4 billion transactions.  However,
-    the functions shown in <xref linkend="functions-pg-snapshot"/>, except
-    <function>age</function> and <function>mxid_age</function>, use a
-    64-bit type <type>xid8</type> that does not wrap around during the life
-    of an installation and can be converted to <type>xid</type> by casting if
-    required;  see <xref linkend="transaction-id"/> for details.
-    The data type <type>pg_snapshot</type> stores information about
-    transaction ID visibility at a particular moment in time.  Its components
-    are described in <xref linkend="functions-pg-snapshot-parts"/>.
-    <type>pg_snapshot</type>'s textual representation is
-    <literal><replaceable>xmin</replaceable>:<replaceable>xmax</replaceable>:<replaceable>xip_list</replaceable></literal>.
-    For example <literal>10:20:10,14,15</literal> means
-    <literal>xmin=10, xmax=20, xip_list=10, 14, 15</literal>.
-   </para>
-
-   <table id="functions-pg-snapshot-parts">
-    <title>Snapshot Components</title>
-    <tgroup cols="2">
-     <thead>
-      <row>
-       <entry>Name</entry>
-       <entry>Description</entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry><structfield>xmin</structfield></entry>
-       <entry>
-         Lowest transaction ID that was still active.  All transaction IDs
-         less than <structfield>xmin</structfield> are either committed and visible,
-         or rolled back and dead.
-       </entry>
-      </row>
-
-      <row>
-       <entry><structfield>xmax</structfield></entry>
-       <entry>
-         One past the highest completed transaction ID.  All transaction IDs
-         greater than or equal to <structfield>xmax</structfield> had not yet
-         completed as of the time of the snapshot, and thus are invisible.
-       </entry>
-      </row>
-
-      <row>
-       <entry><structfield>xip_list</structfield></entry>
-       <entry>
-        Transactions in progress at the time of the snapshot.  A transaction
-        ID that is <literal>xmin &lt;= <replaceable>X</replaceable> &lt;
-        xmax</literal> and not in this list was already completed at the time
-        of the snapshot, and thus is either visible or dead according to its
-        commit status.  This list does not include the transaction IDs of
-        subtransactions (subxids).
-       </entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    In releases of <productname>PostgreSQL</productname> before 13 there was
-    no <type>xid8</type> type, so variants of these functions were provided
-    that used <type>bigint</type> to represent a 64-bit XID, with a
-    correspondingly distinct snapshot data type <type>txid_snapshot</type>.
-    These older functions have <literal>txid</literal> in their names.  They
-    are still supported for backward compatibility, but may be removed from a
-    future release. See <xref linkend="functions-txid-snapshot"/>.
-   </para>
-
-   <table id="functions-txid-snapshot">
-    <title>Deprecated Transaction ID and Snapshot Information Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>txid_current</primary>
-        </indexterm>
-        <function>txid_current</function> ()
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        See <function>pg_current_xact_id()</function>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>txid_current_if_assigned</primary>
-        </indexterm>
-        <function>txid_current_if_assigned</function> ()
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        See <function>pg_current_xact_id_if_assigned()</function>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>txid_current_snapshot</primary>
-        </indexterm>
-        <function>txid_current_snapshot</function> ()
-        <returnvalue>txid_snapshot</returnvalue>
-       </para>
-       <para>
-        See <function>pg_current_snapshot()</function>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>txid_snapshot_xip</primary>
-        </indexterm>
-        <function>txid_snapshot_xip</function> ( <type>txid_snapshot</type> )
-        <returnvalue>setof bigint</returnvalue>
-       </para>
-       <para>
-        See <function>pg_snapshot_xip()</function>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>txid_snapshot_xmax</primary>
-        </indexterm>
-        <function>txid_snapshot_xmax</function> ( <type>txid_snapshot</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        See <function>pg_snapshot_xmax()</function>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>txid_snapshot_xmin</primary>
-        </indexterm>
-        <function>txid_snapshot_xmin</function> ( <type>txid_snapshot</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        See <function>pg_snapshot_xmin()</function>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>txid_visible_in_snapshot</primary>
-        </indexterm>
-        <function>txid_visible_in_snapshot</function> ( <type>bigint</type>, <type>txid_snapshot</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        See <function>pg_visible_in_snapshot()</function>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>txid_status</primary>
-        </indexterm>
-        <function>txid_status</function> ( <type>bigint</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        See <function>pg_xact_status()</function>.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  </sect2>
-
-  <sect2 id="functions-info-commit-timestamp">
-   <title>Committed Transaction Information Functions</title>
-
-   <para>
-    The functions shown in <xref linkend="functions-commit-timestamp"/>
-    provide information about when past transactions were committed.
-    They only provide useful data when the
-    <xref linkend="guc-track-commit-timestamp"/> configuration option is
-    enabled, and only for transactions that were committed after it was
-    enabled.  Commit timestamp information is routinely removed during
-    vacuum.
-   </para>
-
-   <table id="functions-commit-timestamp">
-    <title>Committed Transaction Information Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_xact_commit_timestamp</primary>
-        </indexterm>
-        <function>pg_xact_commit_timestamp</function> ( <type>xid</type> )
-        <returnvalue>timestamp with time zone</returnvalue>
-       </para>
-       <para>
-        Returns the commit timestamp of a transaction.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_xact_commit_timestamp_origin</primary>
-        </indexterm>
-        <function>pg_xact_commit_timestamp_origin</function> ( <type>xid</type> )
-        <returnvalue>record</returnvalue>
-        ( <parameter>timestamp</parameter> <type>timestamp with time zone</type>,
-         <parameter>roident</parameter> <type>oid</type>)
-       </para>
-       <para>
-         Returns the commit timestamp and replication origin of a transaction.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_last_committed_xact</primary>
-        </indexterm>
-        <function>pg_last_committed_xact</function> ()
-        <returnvalue>record</returnvalue>
-        ( <parameter>xid</parameter> <type>xid</type>,
-        <parameter>timestamp</parameter> <type>timestamp with time zone</type>,
-        <parameter>roident</parameter> <type>oid</type> )
-       </para>
-       <para>
-        Returns the transaction ID, commit timestamp and replication origin
-        of the latest committed transaction.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  </sect2>
-
-  <sect2 id="functions-info-controldata">
-   <title>Control Data Functions</title>
-
-   <para>
-    The functions shown in <xref linkend="functions-controldata"/>
-    print information initialized during <command>initdb</command>, such
-    as the catalog version. They also show information about write-ahead
-    logging and checkpoint processing. This information is cluster-wide,
-    not specific to any one database. These functions provide most of the same
-    information, from the same source, as the
-    <xref linkend="app-pgcontroldata"/> application.
-   </para>
-
-   <table id="functions-controldata">
-    <title>Control Data Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_control_checkpoint</primary>
-        </indexterm>
-        <function>pg_control_checkpoint</function> ()
-        <returnvalue>record</returnvalue>
-       </para>
-       <para>
-        Returns information about current checkpoint state, as shown in
-        <xref linkend="functions-pg-control-checkpoint"/>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_control_system</primary>
-        </indexterm>
-        <function>pg_control_system</function> ()
-        <returnvalue>record</returnvalue>
-       </para>
-       <para>
-        Returns information about current control file state, as shown in
-        <xref linkend="functions-pg-control-system"/>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_control_init</primary>
-        </indexterm>
-        <function>pg_control_init</function> ()
-        <returnvalue>record</returnvalue>
-       </para>
-       <para>
-        Returns information about cluster initialization state, as shown in
-        <xref linkend="functions-pg-control-init"/>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_control_recovery</primary>
-        </indexterm>
-        <function>pg_control_recovery</function> ()
-        <returnvalue>record</returnvalue>
-       </para>
-       <para>
-        Returns information about recovery state, as shown in
-        <xref linkend="functions-pg-control-recovery"/>.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <table id="functions-pg-control-checkpoint">
-    <title><function>pg_control_checkpoint</function> Output Columns</title>
-    <tgroup cols="2">
-     <thead>
-      <row>
-       <entry>Column Name</entry>
-       <entry>Data Type</entry>
-      </row>
-     </thead>
-
-     <tbody>
-
-      <row>
-       <entry><structfield>checkpoint_lsn</structfield></entry>
-       <entry><type>pg_lsn</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>redo_lsn</structfield></entry>
-       <entry><type>pg_lsn</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>redo_wal_file</structfield></entry>
-       <entry><type>text</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>timeline_id</structfield></entry>
-       <entry><type>integer</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>prev_timeline_id</structfield></entry>
-       <entry><type>integer</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>full_page_writes</structfield></entry>
-       <entry><type>boolean</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>next_xid</structfield></entry>
-       <entry><type>text</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>next_oid</structfield></entry>
-       <entry><type>oid</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>next_multixact_id</structfield></entry>
-       <entry><type>xid</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>next_multi_offset</structfield></entry>
-       <entry><type>xid</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>oldest_xid</structfield></entry>
-       <entry><type>xid</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>oldest_xid_dbid</structfield></entry>
-       <entry><type>oid</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>oldest_active_xid</structfield></entry>
-       <entry><type>xid</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>oldest_multi_xid</structfield></entry>
-       <entry><type>xid</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>oldest_multi_dbid</structfield></entry>
-       <entry><type>oid</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>oldest_commit_ts_xid</structfield></entry>
-       <entry><type>xid</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>newest_commit_ts_xid</structfield></entry>
-       <entry><type>xid</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>checkpoint_time</structfield></entry>
-       <entry><type>timestamp with time zone</type></entry>
-      </row>
-
-     </tbody>
-    </tgroup>
-   </table>
-
-   <table id="functions-pg-control-system">
-    <title><function>pg_control_system</function> Output Columns</title>
-    <tgroup cols="2">
-     <thead>
-      <row>
-       <entry>Column Name</entry>
-       <entry>Data Type</entry>
-      </row>
-     </thead>
-
-     <tbody>
-
-      <row>
-       <entry><structfield>pg_control_version</structfield></entry>
-       <entry><type>integer</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>catalog_version_no</structfield></entry>
-       <entry><type>integer</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>system_identifier</structfield></entry>
-       <entry><type>bigint</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>pg_control_last_modified</structfield></entry>
-       <entry><type>timestamp with time zone</type></entry>
-      </row>
-
-     </tbody>
-    </tgroup>
-   </table>
-
-   <table id="functions-pg-control-init">
-    <title><function>pg_control_init</function> Output Columns</title>
-    <tgroup cols="2">
-     <thead>
-      <row>
-       <entry>Column Name</entry>
-       <entry>Data Type</entry>
-      </row>
-     </thead>
-
-     <tbody>
-
-      <row>
-       <entry><structfield>max_data_alignment</structfield></entry>
-       <entry><type>integer</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>database_block_size</structfield></entry>
-       <entry><type>integer</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>blocks_per_segment</structfield></entry>
-       <entry><type>integer</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>wal_block_size</structfield></entry>
-       <entry><type>integer</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>bytes_per_wal_segment</structfield></entry>
-       <entry><type>integer</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>max_identifier_length</structfield></entry>
-       <entry><type>integer</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>max_index_columns</structfield></entry>
-       <entry><type>integer</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>max_toast_chunk_size</structfield></entry>
-       <entry><type>integer</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>large_object_chunk_size</structfield></entry>
-       <entry><type>integer</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>float8_pass_by_value</structfield></entry>
-       <entry><type>boolean</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>data_page_checksum_version</structfield></entry>
-       <entry><type>integer</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>default_char_signedness</structfield></entry>
-       <entry><type>boolean</type></entry>
-      </row>
-
-     </tbody>
-    </tgroup>
-   </table>
-
-   <table id="functions-pg-control-recovery">
-    <title><function>pg_control_recovery</function> Output Columns</title>
-    <tgroup cols="2">
-     <thead>
-      <row>
-       <entry>Column Name</entry>
-       <entry>Data Type</entry>
-      </row>
-     </thead>
-
-     <tbody>
-
-      <row>
-       <entry><structfield>min_recovery_end_lsn</structfield></entry>
-       <entry><type>pg_lsn</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>min_recovery_end_timeline</structfield></entry>
-       <entry><type>integer</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>backup_start_lsn</structfield></entry>
-       <entry><type>pg_lsn</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>backup_end_lsn</structfield></entry>
-       <entry><type>pg_lsn</type></entry>
-      </row>
-
-      <row>
-       <entry><structfield>end_of_backup_record_required</structfield></entry>
-       <entry><type>boolean</type></entry>
-      </row>
-
-     </tbody>
-    </tgroup>
-   </table>
-
-  </sect2>
-
-  <sect2 id="functions-info-version">
-   <title>Version Information Functions</title>
-
-   <para>
-    The functions shown in <xref linkend="functions-version"/>
-    print version information.
-   </para>
-
-   <table id="functions-version">
-    <title>Version Information Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>version</primary>
-        </indexterm>
-        <function>version</function> ()
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns a string describing the <productname>PostgreSQL</productname>
-        server's version.  You can also get this information from
-        <xref linkend="guc-server-version"/>, or for a machine-readable
-        version use <xref linkend="guc-server-version-num"/>.  Software
-        developers should use <varname>server_version_num</varname> (available
-        since 8.2) or <xref linkend="libpq-PQserverVersion"/> instead of
-        parsing the text version.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>unicode_version</primary>
-        </indexterm>
-        <function>unicode_version</function> ()
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns a string representing the version of Unicode used by
-        <productname>PostgreSQL</productname>.
-       </para></entry>
-      </row>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>icu_unicode_version</primary>
-        </indexterm>
-        <function>icu_unicode_version</function> ()
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns a string representing the version of Unicode used by ICU, if
-        the server was built with ICU support; otherwise returns
-        <literal>NULL</literal> </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  </sect2>
-
-  <sect2 id="functions-info-wal-summary">
-   <title>WAL Summarization Information Functions</title>
-
-   <para>
-    The functions shown in <xref linkend="functions-wal-summary"/>
-    print information about the status of WAL summarization.
-    See <xref linkend="guc-summarize-wal" />.
-   </para>
-
-   <table id="functions-wal-summary">
-    <title>WAL Summarization Information Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_available_wal_summaries</primary>
-        </indexterm>
-        <function>pg_available_wal_summaries</function> ()
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>tli</parameter> <type>bigint</type>,
-        <parameter>start_lsn</parameter> <type>pg_lsn</type>,
-        <parameter>end_lsn</parameter> <type>pg_lsn</type> )
-       </para>
-       <para>
-        Returns information about the WAL summary files present in the
-        data directory, under <literal>pg_wal/summaries</literal>.
-        One row will be returned per WAL summary file. Each file summarizes
-        WAL on the indicated TLI within the indicated LSN range. This function
-        might be useful to determine whether enough WAL summaries are present
-        on the server to take an incremental backup based on some prior
-        backup whose start LSN is known.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_wal_summary_contents</primary>
-        </indexterm>
-        <function>pg_wal_summary_contents</function> ( <parameter>tli</parameter> <type>bigint</type>, <parameter>start_lsn</parameter> <type>pg_lsn</type>, <parameter>end_lsn</parameter> <type>pg_lsn</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>relfilenode</parameter> <type>oid</type>,
-        <parameter>reltablespace</parameter> <type>oid</type>,
-        <parameter>reldatabase</parameter> <type>oid</type>,
-        <parameter>relforknumber</parameter> <type>smallint</type>,
-        <parameter>relblocknumber</parameter> <type>bigint</type>,
-        <parameter>is_limit_block</parameter> <type>boolean</type> )
-       </para>
-       <para>
-        Returns one information about the contents of a single WAL summary file
-        identified by TLI and starting and ending LSNs. Each row with
-        <literal>is_limit_block</literal> false indicates that the block
-        identified by the remaining output columns was modified by at least
-        one WAL record within the range of records summarized by this file.
-        Each row with <literal>is_limit_block</literal> true indicates either
-        that (a) the relation fork was truncated to the length given by
-        <literal>relblocknumber</literal> within the relevant range of WAL
-        records or (b) that the relation fork was created or dropped within
-        the relevant range of WAL records; in such cases,
-        <literal>relblocknumber</literal> will be zero.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_wal_summarizer_state</primary>
-        </indexterm>
-        <function>pg_get_wal_summarizer_state</function> ()
-        <returnvalue>record</returnvalue>
-        ( <parameter>summarized_tli</parameter> <type>bigint</type>,
-        <parameter>summarized_lsn</parameter> <type>pg_lsn</type>,
-        <parameter>pending_lsn</parameter> <type>pg_lsn</type>,
-        <parameter>summarizer_pid</parameter> <type>int</type> )
-       </para>
-       <para>
-        Returns information about the progress of the WAL summarizer. If the
-        WAL summarizer has never run since the instance was started, then
-        <literal>summarized_tli</literal> and <literal>summarized_lsn</literal>
-        will be <literal>0</literal> and <literal>0/0</literal> respectively;
-        otherwise, they will be the TLI and ending LSN of the last WAL summary
-        file written to disk. If the WAL summarizer is currently running,
-        <literal>pending_lsn</literal> will be the ending LSN of the last
-        record that it has consumed, which must always be greater than or
-        equal to <literal>summarized_lsn</literal>; if the WAL summarizer is
-        not running, it will be equal to <literal>summarized_lsn</literal>.
-        <literal>summarizer_pid</literal> is the PID of the WAL summarizer
-        process, if it is running, and otherwise NULL.
-       </para>
-       <para>
-        As a special exception, the WAL summarizer will refuse to generate
-        WAL summary files if run on WAL generated under
-        <literal>wal_level=minimal</literal>, since such summaries would be
-        unsafe to use as the basis for an incremental backup. In this case,
-        the fields above will continue to advance as if summaries were being
-        generated, but nothing will be written to disk. Once the summarizer
-        reaches WAL generated while <literal>wal_level</literal> was set
-        to <literal>replica</literal> or higher, it will resume writing
-        summaries to disk.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  </sect2>
-
-  </sect1>
-
-  <sect1 id="functions-admin">
-   <title>System Administration Functions</title>
-
-   <para>
-    The functions described in this section are used to control and
-    monitor a <productname>PostgreSQL</productname> installation.
-   </para>
-
-  <sect2 id="functions-admin-set">
-   <title>Configuration Settings Functions</title>
-
-   <indexterm>
-    <primary>SET</primary>
-   </indexterm>
-
-   <indexterm>
-    <primary>SHOW</primary>
-   </indexterm>
-
-   <indexterm>
-    <primary>configuration</primary>
-    <secondary sortas="server">of the server</secondary>
-    <tertiary>functions</tertiary>
-   </indexterm>
-
-   <para>
-    <xref linkend="functions-admin-set-table"/> shows the functions
-    available to query and alter run-time configuration parameters.
-   </para>
-
-   <table id="functions-admin-set-table">
-    <title>Configuration Settings Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example(s)
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>current_setting</primary>
-        </indexterm>
-        <function>current_setting</function> ( <parameter>setting_name</parameter> <type>text</type> <optional>, <parameter>missing_ok</parameter> <type>boolean</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the current value of the
-        setting <parameter>setting_name</parameter>.  If there is no such
-        setting, <function>current_setting</function> throws an error
-        unless <parameter>missing_ok</parameter> is supplied and
-        is <literal>true</literal> (in which case NULL is returned).
-        This function corresponds to
-        the <acronym>SQL</acronym> command <xref linkend="sql-show"/>.
-       </para>
-       <para>
-        <literal>current_setting('datestyle')</literal>
-        <returnvalue>ISO, MDY</returnvalue>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>set_config</primary>
-        </indexterm>
-        <function>set_config</function> (
-          <parameter>setting_name</parameter> <type>text</type>,
-          <parameter>new_value</parameter> <type>text</type>,
-          <parameter>is_local</parameter> <type>boolean</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Sets the parameter <parameter>setting_name</parameter>
-        to <parameter>new_value</parameter>, and returns that value.
-        If <parameter>is_local</parameter> is <literal>true</literal>, the new
-        value will only apply during the current transaction. If you want the
-        new value to apply for the rest of the current session,
-        use <literal>false</literal> instead. This function corresponds to
-        the SQL command <xref linkend="sql-set"/>.
-       </para>
-       <para>
-        <function>set_config</function> accepts the NULL value for
-        <parameter>new_value</parameter>, but as settings cannot be null, it
-        is interpreted as a request to reset the setting to its default value.
-       </para>
-       <para>
-        <literal>set_config('log_statement_stats', 'off', false)</literal>
-        <returnvalue>off</returnvalue>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  </sect2>
-
-  <sect2 id="functions-admin-signal">
-   <title>Server Signaling Functions</title>
-
-   <indexterm>
-    <primary>signal</primary>
-    <secondary sortas="backend">backend processes</secondary>
-   </indexterm>
-
-   <para>
-    The functions shown in <xref
-    linkend="functions-admin-signal-table"/> send control signals to
-    other server processes.  Use of these functions is restricted to
-    superusers by default but access may be granted to others using
-    <command>GRANT</command>, with noted exceptions.
-   </para>
-
-   <para>
-    Each of these functions returns <literal>true</literal> if
-    the signal was successfully sent and <literal>false</literal>
-    if sending the signal failed.
-   </para>
-
-   <table id="functions-admin-signal-table">
-    <title>Server Signaling Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_cancel_backend</primary>
-        </indexterm>
-        <function>pg_cancel_backend</function> ( <parameter>pid</parameter> <type>integer</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Cancels the current query of the session whose backend process has the
-        specified process ID.  This is also allowed if the
-        calling role is a member of the role whose backend is being canceled or
-        the calling role has privileges of <literal>pg_signal_backend</literal>,
-        however only superusers can cancel superuser backends.
-        As an exception, roles with privileges of
-        <literal>pg_signal_autovacuum_worker</literal> are permitted to
-        cancel autovacuum worker processes, which are otherwise considered
-        superuser backends.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_log_backend_memory_contexts</primary>
-        </indexterm>
-        <function>pg_log_backend_memory_contexts</function> ( <parameter>pid</parameter> <type>integer</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Requests to log the memory contexts of the backend with the
-        specified process ID.  This function can send the request to
-        backends and auxiliary processes except logger.  These memory contexts
-        will be logged at
-        <literal>LOG</literal> message level. They will appear in
-        the server log based on the log configuration set
-        (see <xref linkend="runtime-config-logging"/> for more information),
-        but will not be sent to the client regardless of
-        <xref linkend="guc-client-min-messages"/>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_reload_conf</primary>
-        </indexterm>
-        <function>pg_reload_conf</function> ()
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Causes all processes of the <productname>PostgreSQL</productname>
-        server to reload their configuration files.  (This is initiated by
-        sending a <systemitem>SIGHUP</systemitem> signal to the postmaster
-        process, which in turn sends <systemitem>SIGHUP</systemitem> to each
-        of its children.) You can use the
-        <link linkend="view-pg-file-settings"><structname>pg_file_settings</structname></link>,
-        <link linkend="view-pg-hba-file-rules"><structname>pg_hba_file_rules</structname></link> and
-        <link linkend="view-pg-ident-file-mappings"><structname>pg_ident_file_mappings</structname></link> views
-        to check the configuration files for possible errors, before reloading.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_rotate_logfile</primary>
-        </indexterm>
-        <function>pg_rotate_logfile</function> ()
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Signals the log-file manager to switch to a new output file
-        immediately.  This works only when the built-in log collector is
-        running, since otherwise there is no log-file manager subprocess.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_terminate_backend</primary>
-        </indexterm>
-        <function>pg_terminate_backend</function> ( <parameter>pid</parameter> <type>integer</type>, <parameter>timeout</parameter> <type>bigint</type> <literal>DEFAULT</literal> <literal>0</literal> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Terminates the session whose backend process has the
-        specified process ID.  This is also allowed if the calling role
-        is a member of the role whose backend is being terminated or the
-        calling role has privileges of <literal>pg_signal_backend</literal>,
-        however only superusers can terminate superuser backends.
-        As an exception, roles with privileges of
-        <literal>pg_signal_autovacuum_worker</literal> are permitted to
-        terminate autovacuum worker processes, which are otherwise considered
-        superuser backends.
-       </para>
-       <para>
-        If <parameter>timeout</parameter> is not specified or zero, this
-        function returns <literal>true</literal> whether the process actually
-        terminates or not, indicating only that the sending of the signal was
-        successful.  If the <parameter>timeout</parameter> is specified (in
-        milliseconds) and greater than zero, the function waits until the
-        process is actually terminated or until the given time has passed. If
-        the process is terminated, the function
-        returns <literal>true</literal>.  On timeout, a warning is emitted and
-        <literal>false</literal> is returned.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    <function>pg_cancel_backend</function> and <function>pg_terminate_backend</function>
-    send signals (<systemitem>SIGINT</systemitem> or <systemitem>SIGTERM</systemitem>
-    respectively) to backend processes identified by process ID.
-    The process ID of an active backend can be found from
-    the <structfield>pid</structfield> column of the
-    <structname>pg_stat_activity</structname> view, or by listing the
-    <command>postgres</command> processes on the server (using
-    <application>ps</application> on Unix or the <application>Task
-    Manager</application> on <productname>Windows</productname>).
-    The role of an active backend can be found from the
-    <structfield>usename</structfield> column of the
-    <structname>pg_stat_activity</structname> view.
-   </para>
-
-   <para>
-    <function>pg_log_backend_memory_contexts</function> can be used
-    to log the memory contexts of a backend process. For example:
-<programlisting>
-postgres=# SELECT pg_log_backend_memory_contexts(pg_backend_pid());
- pg_log_backend_memory_contexts
---------------------------------
- t
-(1 row)
-</programlisting>
-One message for each memory context will be logged. For example:
-<screen>
-LOG:  logging memory contexts of PID 10377
-STATEMENT:  SELECT pg_log_backend_memory_contexts(pg_backend_pid());
-LOG:  level: 1; TopMemoryContext: 80800 total in 6 blocks; 14432 free (5 chunks); 66368 used
-LOG:  level: 2; pgstat TabStatusArray lookup hash table: 8192 total in 1 blocks; 1408 free (0 chunks); 6784 used
-LOG:  level: 2; TopTransactionContext: 8192 total in 1 blocks; 7720 free (1 chunks); 472 used
-LOG:  level: 2; RowDescriptionContext: 8192 total in 1 blocks; 6880 free (0 chunks); 1312 used
-LOG:  level: 2; MessageContext: 16384 total in 2 blocks; 5152 free (0 chunks); 11232 used
-LOG:  level: 2; Operator class cache: 8192 total in 1 blocks; 512 free (0 chunks); 7680 used
-LOG:  level: 2; smgr relation table: 16384 total in 2 blocks; 4544 free (3 chunks); 11840 used
-LOG:  level: 2; TransactionAbortContext: 32768 total in 1 blocks; 32504 free (0 chunks); 264 used
-...
-LOG:  level: 2; ErrorContext: 8192 total in 1 blocks; 7928 free (3 chunks); 264 used
-LOG:  Grand total: 1651920 bytes in 201 blocks; 622360 free (88 chunks); 1029560 used
-</screen>
-    If there are more than 100 child contexts under the same parent, the first
-    100 child contexts are logged, along with a summary of the remaining contexts.
-    Note that frequent calls to this function could incur significant overhead,
-    because it may generate a large number of log messages.
-   </para>
-
-  </sect2>
-
-  <sect2 id="functions-admin-backup">
-   <title>Backup Control Functions</title>
-
-   <indexterm>
-    <primary>backup</primary>
-   </indexterm>
-
-   <para>
-    The functions shown in <xref
-    linkend="functions-admin-backup-table"/> assist in making on-line backups.
-    These functions cannot be executed during recovery (except
-    <function>pg_backup_start</function>,
-    <function>pg_backup_stop</function>,
-    and <function>pg_wal_lsn_diff</function>).
-   </para>
-
-   <para>
-    For details about proper usage of these functions, see
-    <xref linkend="continuous-archiving"/>.
-   </para>
-
-   <table id="functions-admin-backup-table">
-    <title>Backup Control Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_create_restore_point</primary>
-        </indexterm>
-        <function>pg_create_restore_point</function> ( <parameter>name</parameter> <type>text</type> )
-        <returnvalue>pg_lsn</returnvalue>
-       </para>
-       <para>
-        Creates a named marker record in the write-ahead log that can later be
-        used as a recovery target, and returns the corresponding write-ahead
-        log location.  The given name can then be used with
-        <xref linkend="guc-recovery-target-name"/> to specify the point up to
-        which recovery will proceed.  Avoid creating multiple restore points
-        with the same name, since recovery will stop at the first one whose
-        name matches the recovery target.
-       </para>
-       <para>
-        This function is restricted to superusers by default, but other users
-        can be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_current_wal_flush_lsn</primary>
-        </indexterm>
-        <function>pg_current_wal_flush_lsn</function> ()
-        <returnvalue>pg_lsn</returnvalue>
-       </para>
-       <para>
-        Returns the current write-ahead log flush location (see notes below).
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_current_wal_insert_lsn</primary>
-        </indexterm>
-        <function>pg_current_wal_insert_lsn</function> ()
-        <returnvalue>pg_lsn</returnvalue>
-       </para>
-       <para>
-        Returns the current write-ahead log insert location (see notes below).
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_current_wal_lsn</primary>
-        </indexterm>
-        <function>pg_current_wal_lsn</function> ()
-        <returnvalue>pg_lsn</returnvalue>
-       </para>
-       <para>
-        Returns the current write-ahead log write location (see notes below).
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_backup_start</primary>
-        </indexterm>
-        <function>pg_backup_start</function> (
-          <parameter>label</parameter> <type>text</type>
-          <optional>, <parameter>fast</parameter> <type>boolean</type>
-          </optional> )
-        <returnvalue>pg_lsn</returnvalue>
-       </para>
-       <para>
-        Prepares the server to begin an on-line backup.  The only required
-        parameter is an arbitrary user-defined label for the backup.
-        (Typically this would be the name under which the backup dump file
-        will be stored.)
-        If the optional second parameter is given as <literal>true</literal>,
-        it specifies executing <function>pg_backup_start</function> as quickly
-        as possible.  This forces an immediate checkpoint which will cause a
-        spike in I/O operations, slowing any concurrently executing queries.
-       </para>
-       <para>
-        This function is restricted to superusers by default, but other users
-        can be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_backup_stop</primary>
-        </indexterm>
-        <function>pg_backup_stop</function> (
-          <optional><parameter>wait_for_archive</parameter> <type>boolean</type>
-          </optional> )
-        <returnvalue>record</returnvalue>
-        ( <parameter>lsn</parameter> <type>pg_lsn</type>,
-        <parameter>labelfile</parameter> <type>text</type>,
-        <parameter>spcmapfile</parameter> <type>text</type> )
-       </para>
-       <para>
-        Finishes performing an on-line backup.  The desired contents of the
-        backup label file and the tablespace map file are returned as part of
-        the result of the function and must be written to files in the
-        backup area.  These files must not be written to the live data directory
-        (doing so will cause PostgreSQL to fail to restart in the event of a
-        crash).
-       </para>
-       <para>
-        There is an optional parameter of type <type>boolean</type>.
-        If false, the function will return immediately after the backup is
-        completed, without waiting for WAL to be archived.  This behavior is
-        only useful with backup software that independently monitors WAL
-        archiving.  Otherwise, WAL required to make the backup consistent might
-        be missing and make the backup useless.  By default or when this
-        parameter is true, <function>pg_backup_stop</function> will wait for
-        WAL to be archived when archiving is enabled.  (On a standby, this
-        means that it will wait only when <varname>archive_mode</varname> =
-        <literal>always</literal>.  If write activity on the primary is low,
-        it may be useful to run <function>pg_switch_wal</function> on the
-        primary in order to trigger an immediate segment switch.)
-       </para>
-       <para>
-        When executed on a primary, this function also creates a backup
-        history file in the write-ahead log archive area.  The history file
-        includes the label given to <function>pg_backup_start</function>, the
-        starting and ending write-ahead log locations for the backup, and the
-        starting and ending times of the backup.  After recording the ending
-        location, the current write-ahead log insertion point is automatically
-        advanced to the next write-ahead log file, so that the ending
-        write-ahead log file can be archived immediately to complete the
-        backup.
-       </para>
-       <para>
-        The result of the function is a single record.
-        The <parameter>lsn</parameter> column holds the backup's ending
-        write-ahead log location (which again can be ignored).  The second
-        column returns the contents of the backup label file, and the third
-        column returns the contents of the tablespace map file.  These must be
-        stored as part of the backup and are required as part of the restore
-        process.
-       </para>
-       <para>
-        This function is restricted to superusers by default, but other users
-        can be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_switch_wal</primary>
-        </indexterm>
-        <function>pg_switch_wal</function> ()
-        <returnvalue>pg_lsn</returnvalue>
-       </para>
-       <para>
-        Forces the server to switch to a new write-ahead log file, which
-        allows the current file to be archived (assuming you are using
-        continuous archiving).  The result is the ending write-ahead log
-        location plus 1 within the just-completed write-ahead log file.  If
-        there has been no write-ahead log activity since the last write-ahead
-        log switch, <function>pg_switch_wal</function> does nothing and
-        returns the start location of the write-ahead log file currently in
-        use.
-       </para>
-       <para>
-        This function is restricted to superusers by default, but other users
-        can be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_walfile_name</primary>
-        </indexterm>
-        <function>pg_walfile_name</function> ( <parameter>lsn</parameter> <type>pg_lsn</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts a write-ahead log location to the name of the WAL file
-        holding that location.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_walfile_name_offset</primary>
-        </indexterm>
-        <function>pg_walfile_name_offset</function> ( <parameter>lsn</parameter> <type>pg_lsn</type> )
-        <returnvalue>record</returnvalue>
-        ( <parameter>file_name</parameter> <type>text</type>,
-        <parameter>file_offset</parameter> <type>integer</type> )
-       </para>
-       <para>
-        Converts a write-ahead log location to a WAL file name and byte offset
-        within that file.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_split_walfile_name</primary>
-        </indexterm>
-        <function>pg_split_walfile_name</function> ( <parameter>file_name</parameter> <type>text</type> )
-        <returnvalue>record</returnvalue>
-        ( <parameter>segment_number</parameter> <type>numeric</type>,
-        <parameter>timeline_id</parameter> <type>bigint</type> )
-       </para>
-       <para>
-        Extracts the sequence number and timeline ID from a WAL file
-        name.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_wal_lsn_diff</primary>
-        </indexterm>
-        <function>pg_wal_lsn_diff</function> ( <parameter>lsn1</parameter> <type>pg_lsn</type>, <parameter>lsn2</parameter> <type>pg_lsn</type> )
-        <returnvalue>numeric</returnvalue>
-       </para>
-       <para>
-        Calculates the difference in bytes (<parameter>lsn1</parameter> - <parameter>lsn2</parameter>) between two write-ahead log
-        locations.  This can be used
-        with <structname>pg_stat_replication</structname> or some of the
-        functions shown in <xref linkend="functions-admin-backup-table"/> to
-        get the replication lag.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    <function>pg_current_wal_lsn</function> displays the current write-ahead
-    log write location in the same format used by the above functions.
-    Similarly, <function>pg_current_wal_insert_lsn</function> displays the
-    current write-ahead log insertion location
-    and <function>pg_current_wal_flush_lsn</function> displays the current
-    write-ahead log flush location. The insertion location is
-    the <quote>logical</quote> end of the write-ahead log at any instant,
-    while the write location is the end of what has actually been written out
-    from the server's internal buffers, and the flush location is the last
-    location known to be written to durable storage. The write location is the
-    end of what can be examined from outside the server, and is usually what
-    you want if you are interested in archiving partially-complete write-ahead
-    log files.  The insertion and flush locations are made available primarily
-    for server debugging purposes.  These are all read-only operations and do
-    not require superuser permissions.
-   </para>
-
-   <para>
-    You can use <function>pg_walfile_name_offset</function> to extract the
-    corresponding write-ahead log file name and byte offset from
-    a <type>pg_lsn</type> value.  For example:
-<programlisting>
-postgres=# SELECT * FROM pg_walfile_name_offset((pg_backup_stop()).lsn);
-        file_name         | file_offset
---------------------------+-------------
- 00000001000000000000000D |     4039624
-(1 row)
-</programlisting>
-    Similarly, <function>pg_walfile_name</function> extracts just the write-ahead log file name.
-   </para>
-
-   <para>
-    <function>pg_split_walfile_name</function> is useful to compute a
-    <acronym>LSN</acronym> from a file offset and WAL file name, for example:
-<programlisting>
-postgres=# \set file_name '000000010000000100C000AB'
-postgres=# \set offset 256
-postgres=# SELECT '0/0'::pg_lsn + pd.segment_number * ps.setting::int + :offset AS lsn
-  FROM pg_split_walfile_name(:'file_name') pd,
-       pg_show_all_settings() ps
-  WHERE ps.name = 'wal_segment_size';
-      lsn
----------------
- C001/AB000100
-(1 row)
-</programlisting>
-   </para>
-
-  </sect2>
-
-  <sect2 id="functions-recovery-control">
-   <title>Recovery Control Functions</title>
-
-   <para>
-    The functions shown in <xref
-    linkend="functions-recovery-info-table"/> provide information
-    about the current status of a standby server.
-    These functions may be executed both during recovery and in normal running.
-   </para>
-
-   <table id="functions-recovery-info-table">
-    <title>Recovery Information Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_is_in_recovery</primary>
-        </indexterm>
-        <function>pg_is_in_recovery</function> ()
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Returns true if recovery is still in progress.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_last_wal_receive_lsn</primary>
-        </indexterm>
-        <function>pg_last_wal_receive_lsn</function> ()
-        <returnvalue>pg_lsn</returnvalue>
-       </para>
-       <para>
-        Returns the last write-ahead log location that has been received and
-        synced to disk by streaming replication. While streaming replication
-        is in progress this will increase monotonically. If recovery has
-        completed then this will remain static at the location of the last WAL
-        record received and synced to disk during recovery. If streaming
-        replication is disabled, or if it has not yet started, the function
-        returns <literal>NULL</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_last_wal_replay_lsn</primary>
-        </indexterm>
-        <function>pg_last_wal_replay_lsn</function> ()
-        <returnvalue>pg_lsn</returnvalue>
-       </para>
-       <para>
-        Returns the last write-ahead log location that has been replayed
-        during recovery.  If recovery is still in progress this will increase
-        monotonically.  If recovery has completed then this will remain
-        static at the location of the last WAL record applied during recovery.
-        When the server has been started normally without recovery, the
-        function returns <literal>NULL</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_last_xact_replay_timestamp</primary>
-        </indexterm>
-        <function>pg_last_xact_replay_timestamp</function> ()
-        <returnvalue>timestamp with time zone</returnvalue>
-       </para>
-       <para>
-        Returns the time stamp of the last transaction replayed during
-        recovery.  This is the time at which the commit or abort WAL record
-        for that transaction was generated on the primary.  If no transactions
-        have been replayed during recovery, the function
-        returns <literal>NULL</literal>.  Otherwise, if recovery is still in
-        progress this will increase monotonically.  If recovery has completed
-        then this will remain static at the time of the last transaction
-        applied during recovery.  When the server has been started normally
-        without recovery, the function returns <literal>NULL</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_wal_resource_managers</primary>
-        </indexterm>
-        <function>pg_get_wal_resource_managers</function> ()
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>rm_id</parameter> <type>integer</type>,
-        <parameter>rm_name</parameter> <type>text</type>,
-        <parameter>rm_builtin</parameter> <type>boolean</type> )
-       </para>
-       <para>
-        Returns the currently-loaded WAL resource managers in the system. The
-        column <parameter>rm_builtin</parameter> indicates whether it's a
-        built-in resource manager, or a custom resource manager loaded by an
-        extension.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    The functions shown in <xref
-    linkend="functions-recovery-control-table"/> control the progress of recovery.
-    These functions may be executed only during recovery.
-   </para>
-
-   <table id="functions-recovery-control-table">
-    <title>Recovery Control Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_is_wal_replay_paused</primary>
-        </indexterm>
-        <function>pg_is_wal_replay_paused</function> ()
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Returns true if recovery pause is requested.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_get_wal_replay_pause_state</primary>
-        </indexterm>
-        <function>pg_get_wal_replay_pause_state</function> ()
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns recovery pause state.  The return values are <literal>
-        not paused</literal> if pause is not requested, <literal>
-        pause requested</literal> if pause is requested but recovery is
-        not yet paused, and <literal>paused</literal> if the recovery is
-        actually paused.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_promote</primary>
-        </indexterm>
-        <function>pg_promote</function> ( <parameter>wait</parameter> <type>boolean</type> <literal>DEFAULT</literal> <literal>true</literal>, <parameter>wait_seconds</parameter> <type>integer</type> <literal>DEFAULT</literal> <literal>60</literal> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Promotes a standby server to primary status.
-        With <parameter>wait</parameter> set to <literal>true</literal> (the
-        default), the function waits until promotion is completed
-        or <parameter>wait_seconds</parameter> seconds have passed, and
-        returns <literal>true</literal> if promotion is successful
-        and <literal>false</literal> otherwise.
-        If <parameter>wait</parameter> is set to <literal>false</literal>, the
-        function returns <literal>true</literal> immediately after sending a
-        <literal>SIGUSR1</literal> signal to the postmaster to trigger
-        promotion.
-       </para>
-       <para>
-        This function is restricted to superusers by default, but other users
-        can be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_wal_replay_pause</primary>
-        </indexterm>
-        <function>pg_wal_replay_pause</function> ()
-        <returnvalue>void</returnvalue>
-       </para>
-       <para>
-        Request to pause recovery.  A request doesn't mean that recovery stops
-        right away.  If you want a guarantee that recovery is actually paused,
-        you need to check for the recovery pause state returned by
-        <function>pg_get_wal_replay_pause_state()</function>.  Note that
-        <function>pg_is_wal_replay_paused()</function> returns whether a request
-        is made.  While recovery is paused, no further database changes are applied.
-        If hot standby is active, all new queries will see the same consistent
-        snapshot of the database, and no further query conflicts will be generated
-        until recovery is resumed.
-       </para>
-       <para>
-        This function is restricted to superusers by default, but other users
-        can be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_wal_replay_resume</primary>
-        </indexterm>
-        <function>pg_wal_replay_resume</function> ()
-        <returnvalue>void</returnvalue>
-       </para>
-       <para>
-        Restarts recovery if it was paused.
-       </para>
-       <para>
-        This function is restricted to superusers by default, but other users
-        can be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    <function>pg_wal_replay_pause</function> and
-    <function>pg_wal_replay_resume</function> cannot be executed while
-    a promotion is ongoing. If a promotion is triggered while recovery
-    is paused, the paused state ends and promotion continues.
-   </para>
-
-   <para>
-    If streaming replication is disabled, the paused state may continue
-    indefinitely without a problem. If streaming replication is in
-    progress then WAL records will continue to be received, which will
-    eventually fill available disk space, depending upon the duration of
-    the pause, the rate of WAL generation and available disk space.
-   </para>
-
-  </sect2>
-
-  <sect2 id="functions-snapshot-synchronization">
-   <title>Snapshot Synchronization Functions</title>
-
-   <para>
-    <productname>PostgreSQL</productname> allows database sessions to synchronize their
-    snapshots. A <firstterm>snapshot</firstterm> determines which data is visible to the
-    transaction that is using the snapshot. Synchronized snapshots are
-    necessary when two or more sessions need to see identical content in the
-    database. If two sessions just start their transactions independently,
-    there is always a possibility that some third transaction commits
-    between the executions of the two <command>START TRANSACTION</command> commands,
-    so that one session sees the effects of that transaction and the other
-    does not.
-   </para>
-
-   <para>
-    To solve this problem, <productname>PostgreSQL</productname> allows a transaction to
-    <firstterm>export</firstterm> the snapshot it is using.  As long as the exporting
-    transaction remains open, other transactions can <firstterm>import</firstterm> its
-    snapshot, and thereby be guaranteed that they see exactly the same view
-    of the database that the first transaction sees.  But note that any
-    database changes made by any one of these transactions remain invisible
-    to the other transactions, as is usual for changes made by uncommitted
-    transactions.  So the transactions are synchronized with respect to
-    pre-existing data, but act normally for changes they make themselves.
-   </para>
-
-   <para>
-    Snapshots are exported with the <function>pg_export_snapshot</function> function,
-    shown in <xref linkend="functions-snapshot-synchronization-table"/>, and
-    imported with the <xref linkend="sql-set-transaction"/> command.
-   </para>
-
-   <table id="functions-snapshot-synchronization-table">
-    <title>Snapshot Synchronization Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_export_snapshot</primary>
-        </indexterm>
-        <function>pg_export_snapshot</function> ()
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Saves the transaction's current snapshot and returns
-        a <type>text</type> string identifying the snapshot.  This string must
-        be passed (outside the database) to clients that want to import the
-        snapshot.  The snapshot is available for import only until the end of
-        the transaction that exported it.
-       </para>
-       <para>
-        A transaction can export more than one snapshot, if needed.  Note that
-        doing so is only useful in <literal>READ COMMITTED</literal>
-        transactions, since in <literal>REPEATABLE READ</literal> and higher
-        isolation levels, transactions use the same snapshot throughout their
-        lifetime.  Once a transaction has exported any snapshots, it cannot be
-        prepared with <xref linkend="sql-prepare-transaction"/>.
-       </para></entry>
-      </row>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_log_standby_snapshot</primary>
-        </indexterm>
-        <function>pg_log_standby_snapshot</function> ()
-        <returnvalue>pg_lsn</returnvalue>
-       </para>
-       <para>
-        Take a snapshot of running transactions and write it to WAL, without
-        having to wait for bgwriter or checkpointer to log one. This is useful
-        for logical decoding on standby, as logical slot creation has to wait
-        until such a record is replayed on the standby.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  </sect2>
-
-  <sect2 id="functions-replication">
-   <title>Replication Management Functions</title>
-
-   <para>
-    The functions shown
-    in <xref linkend="functions-replication-table"/> are for
-    controlling and interacting with replication features.
-    See <xref linkend="streaming-replication"/>,
-    <xref linkend="streaming-replication-slots"/>, and
-    <xref linkend="replication-origins"/>
-    for information about the underlying features.
-    Use of functions for replication origin is only allowed to the
-    superuser by default, but may be allowed to other users by using the
-    <literal>GRANT</literal> command.
-    Use of functions for replication slots is restricted to superusers
-    and users having <literal>REPLICATION</literal> privilege.
-   </para>
-
-   <para>
-    Many of these functions have equivalent commands in the replication
-    protocol; see <xref linkend="protocol-replication"/>.
-   </para>
-
-   <para>
-    The functions described in
-    <xref linkend="functions-admin-backup"/>,
-    <xref linkend="functions-recovery-control"/>, and
-    <xref linkend="functions-snapshot-synchronization"/>
-    are also relevant for replication.
-   </para>
-
-   <table id="functions-replication-table">
-    <title>Replication Management Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_create_physical_replication_slot</primary>
-        </indexterm>
-        <function>pg_create_physical_replication_slot</function> ( <parameter>slot_name</parameter> <type>name</type> <optional>, <parameter>immediately_reserve</parameter> <type>boolean</type>, <parameter>temporary</parameter> <type>boolean</type> </optional> )
-        <returnvalue>record</returnvalue>
-        ( <parameter>slot_name</parameter> <type>name</type>,
-        <parameter>lsn</parameter> <type>pg_lsn</type> )
-       </para>
-       <para>
-        Creates a new physical replication slot named
-        <parameter>slot_name</parameter>. The optional second parameter,
-        when <literal>true</literal>, specifies that the <acronym>LSN</acronym> for this
-        replication slot be reserved immediately; otherwise
-        the <acronym>LSN</acronym> is reserved on first connection from a streaming
-        replication client. Streaming changes from a physical slot is only
-        possible with the streaming-replication protocol &mdash;
-        see <xref linkend="protocol-replication"/>. The optional third
-        parameter, <parameter>temporary</parameter>, when set to true, specifies that
-        the slot should not be permanently stored to disk and is only meant
-        for use by the current session. Temporary slots are also
-        released upon any error. This function corresponds
-        to the replication protocol command <literal>CREATE_REPLICATION_SLOT
-        ... PHYSICAL</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_drop_replication_slot</primary>
-        </indexterm>
-        <function>pg_drop_replication_slot</function> ( <parameter>slot_name</parameter> <type>name</type> )
-        <returnvalue>void</returnvalue>
-       </para>
-       <para>
-        Drops the physical or logical replication slot
-        named <parameter>slot_name</parameter>. Same as replication protocol
-        command <literal>DROP_REPLICATION_SLOT</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="pg-create-logical-replication-slot" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_create_logical_replication_slot</primary>
-        </indexterm>
-        <function>pg_create_logical_replication_slot</function> ( <parameter>slot_name</parameter> <type>name</type>, <parameter>plugin</parameter> <type>name</type> <optional>, <parameter>temporary</parameter> <type>boolean</type>, <parameter>twophase</parameter> <type>boolean</type>, <parameter>failover</parameter> <type>boolean</type> </optional> )
-        <returnvalue>record</returnvalue>
-        ( <parameter>slot_name</parameter> <type>name</type>,
-        <parameter>lsn</parameter> <type>pg_lsn</type> )
-       </para>
-       <para>
-        Creates a new logical (decoding) replication slot named
-        <parameter>slot_name</parameter> using the output plugin
-        <parameter>plugin</parameter>. The optional third
-        parameter, <parameter>temporary</parameter>, when set to true, specifies that
-        the slot should not be permanently stored to disk and is only meant
-        for use by the current session. Temporary slots are also
-        released upon any error. The optional fourth parameter,
-        <parameter>twophase</parameter>, when set to true, specifies
-        that the decoding of prepared transactions is enabled for this
-        slot. The optional fifth parameter,
-        <parameter>failover</parameter>, when set to true,
-        specifies that this slot is enabled to be synced to the
-        standbys so that logical replication can be resumed after
-        failover. A call to this function has the same effect as
-        the replication protocol command
-        <literal>CREATE_REPLICATION_SLOT ... LOGICAL</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_copy_physical_replication_slot</primary>
-        </indexterm>
-        <function>pg_copy_physical_replication_slot</function> ( <parameter>src_slot_name</parameter> <type>name</type>, <parameter>dst_slot_name</parameter> <type>name</type> <optional>, <parameter>temporary</parameter> <type>boolean</type> </optional> )
-        <returnvalue>record</returnvalue>
-        ( <parameter>slot_name</parameter> <type>name</type>,
-        <parameter>lsn</parameter> <type>pg_lsn</type> )
-       </para>
-       <para>
-        Copies an existing physical replication slot named <parameter>src_slot_name</parameter>
-        to a physical replication slot named <parameter>dst_slot_name</parameter>.
-        The copied physical slot starts to reserve WAL from the same <acronym>LSN</acronym> as the
-        source slot.
-        <parameter>temporary</parameter> is optional. If <parameter>temporary</parameter>
-        is omitted, the same value as the source slot is used. Copy of an
-        invalidated slot is not allowed.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_copy_logical_replication_slot</primary>
-        </indexterm>
-        <function>pg_copy_logical_replication_slot</function> ( <parameter>src_slot_name</parameter> <type>name</type>, <parameter>dst_slot_name</parameter> <type>name</type> <optional>, <parameter>temporary</parameter> <type>boolean</type> <optional>, <parameter>plugin</parameter> <type>name</type> </optional></optional> )
-        <returnvalue>record</returnvalue>
-        ( <parameter>slot_name</parameter> <type>name</type>,
-        <parameter>lsn</parameter> <type>pg_lsn</type> )
-       </para>
-       <para>
-        Copies an existing logical replication slot
-        named <parameter>src_slot_name</parameter> to a logical replication
-        slot named <parameter>dst_slot_name</parameter>, optionally changing
-        the output plugin and persistence.  The copied logical slot starts
-        from the same <acronym>LSN</acronym> as the source logical slot.  Both
-        <parameter>temporary</parameter> and <parameter>plugin</parameter> are
-        optional; if they are omitted, the values of the source slot are used.
-        The <literal>failover</literal> option of the source logical slot
-        is not copied and is set to <literal>false</literal> by default. This
-        is to avoid the risk of being unable to continue logical replication
-        after failover to standby where the slot is being synchronized. Copy of
-        an invalidated slot is not allowed.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="pg-logical-slot-get-changes" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_logical_slot_get_changes</primary>
-        </indexterm>
-        <function>pg_logical_slot_get_changes</function> ( <parameter>slot_name</parameter> <type>name</type>, <parameter>upto_lsn</parameter> <type>pg_lsn</type>, <parameter>upto_nchanges</parameter> <type>integer</type>, <literal>VARIADIC</literal> <parameter>options</parameter> <type>text[]</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>lsn</parameter> <type>pg_lsn</type>,
-        <parameter>xid</parameter> <type>xid</type>,
-        <parameter>data</parameter> <type>text</type> )
-       </para>
-       <para>
-        Returns changes in the slot <parameter>slot_name</parameter>, starting
-        from the point from which changes have been consumed last.  If
-        <parameter>upto_lsn</parameter>
-        and <parameter>upto_nchanges</parameter> are NULL,
-        logical decoding will continue until end of WAL.  If
-        <parameter>upto_lsn</parameter> is non-NULL, decoding will include only
-        those transactions which commit prior to the specified LSN.  If
-        <parameter>upto_nchanges</parameter> is non-NULL, decoding will
-        stop when the number of rows produced by decoding exceeds
-        the specified value.  Note, however, that the actual number of
-        rows returned may be larger, since this limit is only checked after
-        adding the rows produced when decoding each new transaction commit.
-        If the specified slot is a logical failover slot then the function will
-        not return until all physical slots specified in
-        <link linkend="guc-synchronized-standby-slots"><varname>synchronized_standby_slots</varname></link>
-        have confirmed WAL receipt.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="pg-logical-slot-peek-changes" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_logical_slot_peek_changes</primary>
-        </indexterm>
-        <function>pg_logical_slot_peek_changes</function> ( <parameter>slot_name</parameter> <type>name</type>, <parameter>upto_lsn</parameter> <type>pg_lsn</type>, <parameter>upto_nchanges</parameter> <type>integer</type>, <literal>VARIADIC</literal> <parameter>options</parameter> <type>text[]</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>lsn</parameter> <type>pg_lsn</type>,
-        <parameter>xid</parameter> <type>xid</type>,
-         <parameter>data</parameter> <type>text</type> )
-       </para>
-       <para>
-        Behaves just like
-        the <function>pg_logical_slot_get_changes()</function> function,
-        except that changes are not consumed; that is, they will be returned
-        again on future calls.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="pg-logical-slot-get-binary-changes" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_logical_slot_get_binary_changes</primary>
-        </indexterm>
-        <function>pg_logical_slot_get_binary_changes</function> ( <parameter>slot_name</parameter> <type>name</type>, <parameter>upto_lsn</parameter> <type>pg_lsn</type>, <parameter>upto_nchanges</parameter> <type>integer</type>, <literal>VARIADIC</literal> <parameter>options</parameter> <type>text[]</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>lsn</parameter> <type>pg_lsn</type>,
-        <parameter>xid</parameter> <type>xid</type>,
-        <parameter>data</parameter> <type>bytea</type> )
-       </para>
-       <para>
-        Behaves just like
-        the <function>pg_logical_slot_get_changes()</function> function,
-        except that changes are returned as <type>bytea</type>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_logical_slot_peek_binary_changes</primary>
-        </indexterm>
-        <function>pg_logical_slot_peek_binary_changes</function> ( <parameter>slot_name</parameter> <type>name</type>, <parameter>upto_lsn</parameter> <type>pg_lsn</type>, <parameter>upto_nchanges</parameter> <type>integer</type>, <literal>VARIADIC</literal> <parameter>options</parameter> <type>text[]</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>lsn</parameter> <type>pg_lsn</type>,
-        <parameter>xid</parameter> <type>xid</type>,
-        <parameter>data</parameter> <type>bytea</type> )
-       </para>
-       <para>
-        Behaves just like
-        the <function>pg_logical_slot_peek_changes()</function> function,
-        except that changes are returned as <type>bytea</type>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="pg-replication-slot-advance" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_replication_slot_advance</primary>
-        </indexterm>
-        <function>pg_replication_slot_advance</function> ( <parameter>slot_name</parameter> <type>name</type>, <parameter>upto_lsn</parameter> <type>pg_lsn</type> )
-        <returnvalue>record</returnvalue>
-        ( <parameter>slot_name</parameter> <type>name</type>,
-        <parameter>end_lsn</parameter> <type>pg_lsn</type> )
-       </para>
-       <para>
-        Advances the current confirmed position of a replication slot named
-        <parameter>slot_name</parameter>. The slot will not be moved backwards,
-        and it will not be moved beyond the current insert location. Returns
-        the name of the slot and the actual position that it was advanced to.
-        The updated slot position information is written out at the next
-        checkpoint if any advancing is done. So in the event of a crash, the
-        slot may return to an earlier position. If the specified slot is a
-        logical failover slot then the function will not return until all
-        physical slots specified in
-        <link linkend="guc-synchronized-standby-slots"><varname>synchronized_standby_slots</varname></link>
-        have confirmed WAL receipt.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="pg-replication-origin-create" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_replication_origin_create</primary>
-        </indexterm>
-        <function>pg_replication_origin_create</function> ( <parameter>node_name</parameter> <type>text</type> )
-        <returnvalue>oid</returnvalue>
-       </para>
-       <para>
-        Creates a replication origin with the given external
-        name, and returns the internal ID assigned to it.
-        The name must be no longer than 512 bytes.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="pg-replication-origin-drop" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_replication_origin_drop</primary>
-        </indexterm>
-        <function>pg_replication_origin_drop</function> ( <parameter>node_name</parameter> <type>text</type> )
-        <returnvalue>void</returnvalue>
-       </para>
-       <para>
-        Deletes a previously-created replication origin, including any
-        associated replay progress.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_replication_origin_oid</primary>
-        </indexterm>
-        <function>pg_replication_origin_oid</function> ( <parameter>node_name</parameter> <type>text</type> )
-        <returnvalue>oid</returnvalue>
-       </para>
-       <para>
-        Looks up a replication origin by name and returns the internal ID. If
-        no such replication origin is found, <literal>NULL</literal> is
-        returned.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="pg-replication-origin-session-setup" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_replication_origin_session_setup</primary>
-        </indexterm>
-        <function>pg_replication_origin_session_setup</function> ( <parameter>node_name</parameter> <type>text</type> )
-        <returnvalue>void</returnvalue>
-       </para>
-       <para>
-        Marks the current session as replaying from the given
-        origin, allowing replay progress to be tracked.
-        Can only be used if no origin is currently selected.
-        Use <function>pg_replication_origin_session_reset</function> to undo.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_replication_origin_session_reset</primary>
-        </indexterm>
-        <function>pg_replication_origin_session_reset</function> ()
-        <returnvalue>void</returnvalue>
-       </para>
-       <para>
-        Cancels the effects
-        of <function>pg_replication_origin_session_setup()</function>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_replication_origin_session_is_setup</primary>
-        </indexterm>
-        <function>pg_replication_origin_session_is_setup</function> ()
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Returns true if a replication origin has been selected in the
-        current session.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="pg-replication-origin-session-progress" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_replication_origin_session_progress</primary>
-        </indexterm>
-        <function>pg_replication_origin_session_progress</function> ( <parameter>flush</parameter> <type>boolean</type> )
-        <returnvalue>pg_lsn</returnvalue>
-       </para>
-       <para>
-        Returns the replay location for the replication origin selected in
-        the current session. The parameter <parameter>flush</parameter>
-        determines whether the corresponding local transaction will be
-        guaranteed to have been flushed to disk or not.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="pg-replication-origin-xact-setup" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_replication_origin_xact_setup</primary>
-        </indexterm>
-        <function>pg_replication_origin_xact_setup</function> ( <parameter>origin_lsn</parameter> <type>pg_lsn</type>, <parameter>origin_timestamp</parameter> <type>timestamp with time zone</type> )
-        <returnvalue>void</returnvalue>
-       </para>
-       <para>
-        Marks the current transaction as replaying a transaction that has
-        committed at the given <acronym>LSN</acronym> and timestamp. Can
-        only be called when a replication origin has been selected
-        using <function>pg_replication_origin_session_setup</function>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="pg-replication-origin-xact-reset" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_replication_origin_xact_reset</primary>
-        </indexterm>
-        <function>pg_replication_origin_xact_reset</function> ()
-        <returnvalue>void</returnvalue>
-       </para>
-       <para>
-        Cancels the effects of
-        <function>pg_replication_origin_xact_setup()</function>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="pg-replication-origin-advance" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_replication_origin_advance</primary>
-        </indexterm>
-        <function>pg_replication_origin_advance</function> ( <parameter>node_name</parameter> <type>text</type>, <parameter>lsn</parameter> <type>pg_lsn</type> )
-        <returnvalue>void</returnvalue>
-       </para>
-       <para>
-        Sets replication progress for the given node to the given
-        location. This is primarily useful for setting up the initial
-        location, or setting a new location after configuration changes and
-        similar. Be aware that careless use of this function can lead to
-        inconsistently replicated data.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="pg-replication-origin-progress" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_replication_origin_progress</primary>
-        </indexterm>
-        <function>pg_replication_origin_progress</function> ( <parameter>node_name</parameter> <type>text</type>, <parameter>flush</parameter> <type>boolean</type> )
-        <returnvalue>pg_lsn</returnvalue>
-       </para>
-       <para>
-        Returns the replay location for the given replication origin. The
-        parameter <parameter>flush</parameter> determines whether the
-        corresponding local transaction will be guaranteed to have been
-        flushed to disk or not.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="pg-logical-emit-message" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_logical_emit_message</primary>
-        </indexterm>
-        <function>pg_logical_emit_message</function> ( <parameter>transactional</parameter> <type>boolean</type>, <parameter>prefix</parameter> <type>text</type>, <parameter>content</parameter> <type>text</type> <optional>, <parameter>flush</parameter> <type>boolean</type> <literal>DEFAULT</literal> <literal>false</literal></optional> )
-        <returnvalue>pg_lsn</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>pg_logical_emit_message</function> ( <parameter>transactional</parameter> <type>boolean</type>, <parameter>prefix</parameter> <type>text</type>, <parameter>content</parameter> <type>bytea</type> <optional>, <parameter>flush</parameter> <type>boolean</type> <literal>DEFAULT</literal> <literal>false</literal></optional> )
-        <returnvalue>pg_lsn</returnvalue>
-       </para>
-       <para>
-        Emits a logical decoding message. This can be used to pass generic
-        messages to logical decoding plugins through
-        WAL. The <parameter>transactional</parameter> parameter specifies if
-        the message should be part of the current transaction, or if it should
-        be written immediately and decoded as soon as the logical decoder
-        reads the record. The <parameter>prefix</parameter> parameter is a
-        textual prefix that can be used by logical decoding plugins to easily
-        recognize messages that are interesting for them.
-        The <parameter>content</parameter> parameter is the content of the
-        message, given either in text or binary form.
-        The <parameter>flush</parameter> parameter (default set to
-        <literal>false</literal>) controls if the message is immediately
-        flushed to WAL or not. <parameter>flush</parameter> has no effect
-        with <parameter>transactional</parameter>, as the message's WAL
-        record is flushed along with its transaction.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry id="pg-sync-replication-slots" role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_sync_replication_slots</primary>
-        </indexterm>
-        <function>pg_sync_replication_slots</function> ()
-        <returnvalue>void</returnvalue>
-       </para>
-       <para>
-        Synchronize the logical failover replication slots from the primary
-        server to the standby server. This function can only be executed on the
-        standby server. Temporary synced slots, if any, cannot be used for
-        logical decoding and must be dropped after promotion. See
-        <xref linkend="logicaldecoding-replication-slots-synchronization"/> for details.
-        Note that this function is primarily intended for testing and
-        debugging purposes and should be used with caution. Additionaly,
-        this function cannot be executed if
-        <link linkend="guc-sync-replication-slots"><varname>
-        sync_replication_slots</varname></link> is enabled and the slotsync
-        worker is already running to perform the synchronization of slots.
-       </para>
-
-       <caution>
-        <para>
-          If, after executing the function,
-          <link linkend="guc-hot-standby-feedback">
-          <varname>hot_standby_feedback</varname></link> is disabled on
-          the standby or the physical slot configured in
-          <link linkend="guc-primary-slot-name">
-          <varname>primary_slot_name</varname></link> is
-          removed, then it is possible that the necessary rows of the
-          synchronized slot will be removed by the VACUUM process on the primary
-          server, resulting in the synchronized slot becoming invalidated.
-        </para>
-       </caution>
-      </entry>
-      </row>
-
-     </tbody>
-    </tgroup>
-   </table>
-
-  </sect2>
-
-  <sect2 id="functions-admin-dbobject">
-   <title>Database Object Management Functions</title>
-
-   <para>
-    The functions shown in <xref linkend="functions-admin-dbsize"/> calculate
-    the disk space usage of database objects, or assist in presentation
-    or understanding of usage results.  <literal>bigint</literal> results
-    are measured in bytes.  If an OID that does
-    not represent an existing object is passed to one of these
-    functions, <literal>NULL</literal> is returned.
-   </para>
-
-   <table id="functions-admin-dbsize">
-    <title>Database Object Size Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_column_size</primary>
-        </indexterm>
-        <function>pg_column_size</function> ( <type>"any"</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Shows the number of bytes used to store any individual data value.  If
-        applied directly to a table column value, this reflects any
-        compression that was done.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_column_compression</primary>
-        </indexterm>
-        <function>pg_column_compression</function> ( <type>"any"</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Shows the compression algorithm that was used to compress
-        an individual variable-length value. Returns <literal>NULL</literal>
-        if the value is not compressed.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_column_toast_chunk_id</primary>
-        </indexterm>
-        <function>pg_column_toast_chunk_id</function> ( <type>"any"</type> )
-        <returnvalue>oid</returnvalue>
-       </para>
-       <para>
-        Shows the <structfield>chunk_id</structfield> of an on-disk
-        <acronym>TOAST</acronym>ed value.  Returns <literal>NULL</literal>
-        if the value is un-<acronym>TOAST</acronym>ed or not on-disk.  See
-        <xref linkend="storage-toast"/> for more information about
-        <acronym>TOAST</acronym>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_database_size</primary>
-        </indexterm>
-        <function>pg_database_size</function> ( <type>name</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>pg_database_size</function> ( <type>oid</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Computes the total disk space used by the database with the specified
-        name or OID.  To use this function, you must
-        have <literal>CONNECT</literal> privilege on the specified database
-        (which is granted by default) or have privileges of
-        the <literal>pg_read_all_stats</literal> role.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_indexes_size</primary>
-        </indexterm>
-        <function>pg_indexes_size</function> ( <type>regclass</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Computes the total disk space used by indexes attached to the
-        specified table.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_relation_size</primary>
-        </indexterm>
-        <function>pg_relation_size</function> ( <parameter>relation</parameter> <type>regclass</type> <optional>, <parameter>fork</parameter> <type>text</type> </optional> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Computes the disk space used by one <quote>fork</quote> of the
-        specified relation.  (Note that for most purposes it is more
-        convenient to use the higher-level
-        functions <function>pg_total_relation_size</function>
-        or <function>pg_table_size</function>, which sum the sizes of all
-        forks.)  With one argument, this returns the size of the main data
-        fork of the relation.  The second argument can be provided to specify
-        which fork to examine:
-        <itemizedlist spacing="compact">
-         <listitem>
-          <para>
-           <literal>main</literal> returns the size of the main
-           data fork of the relation.
-          </para>
-         </listitem>
-         <listitem>
-          <para>
-           <literal>fsm</literal> returns the size of the Free Space Map
-           (see <xref linkend="storage-fsm"/>) associated with the relation.
-          </para>
-         </listitem>
-         <listitem>
-          <para>
-           <literal>vm</literal> returns the size of the Visibility Map
-           (see <xref linkend="storage-vm"/>) associated with the relation.
-          </para>
-         </listitem>
-         <listitem>
-          <para>
-           <literal>init</literal> returns the size of the initialization
-           fork, if any, associated with the relation.
-          </para>
-         </listitem>
-        </itemizedlist>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_size_bytes</primary>
-        </indexterm>
-        <function>pg_size_bytes</function> ( <type>text</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Converts a size in human-readable format (as returned
-        by <function>pg_size_pretty</function>) into bytes.  Valid units are
-        <literal>bytes</literal>, <literal>B</literal>, <literal>kB</literal>,
-        <literal>MB</literal>, <literal>GB</literal>, <literal>TB</literal>,
-        and <literal>PB</literal>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_size_pretty</primary>
-        </indexterm>
-        <function>pg_size_pretty</function> ( <type>bigint</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>pg_size_pretty</function> ( <type>numeric</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Converts a size in bytes into a more easily human-readable format with
-        size units (bytes, kB, MB, GB, TB, or PB as appropriate).  Note that the
-        units are powers of 2 rather than powers of 10, so 1kB is 1024 bytes,
-        1MB is 1024<superscript>2</superscript> = 1048576 bytes, and so on.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_table_size</primary>
-        </indexterm>
-        <function>pg_table_size</function> ( <type>regclass</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Computes the disk space used by the specified table, excluding indexes
-        (but including its TOAST table if any, free space map, and visibility
-        map).
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_tablespace_size</primary>
-        </indexterm>
-        <function>pg_tablespace_size</function> ( <type>name</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>pg_tablespace_size</function> ( <type>oid</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Computes the total disk space used in the tablespace with the
-        specified name or OID. To use this function, you must
-        have <literal>CREATE</literal> privilege on the specified tablespace
-        or have privileges of the <literal>pg_read_all_stats</literal> role,
-        unless it is the default tablespace for the current database.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_total_relation_size</primary>
-        </indexterm>
-        <function>pg_total_relation_size</function> ( <type>regclass</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Computes the total disk space used by the specified table, including
-        all indexes and <acronym>TOAST</acronym> data.  The result is
-        equivalent to <function>pg_table_size</function>
-        <literal>+</literal> <function>pg_indexes_size</function>.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    The functions above that operate on tables or indexes accept a
-    <type>regclass</type> argument, which is simply the OID of the table or index
-    in the <structname>pg_class</structname> system catalog.  You do not have to look up
-    the OID by hand, however, since the <type>regclass</type> data type's input
-    converter will do the work for you.  See <xref linkend="datatype-oid"/>
-    for details.
-   </para>
-
-   <para>
-    The functions shown in <xref linkend="functions-admin-dblocation"/> assist
-    in identifying the specific disk files associated with database objects.
-   </para>
-
-   <table id="functions-admin-dblocation">
-    <title>Database Object Location Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_relation_filenode</primary>
-        </indexterm>
-        <function>pg_relation_filenode</function> ( <parameter>relation</parameter> <type>regclass</type> )
-        <returnvalue>oid</returnvalue>
-       </para>
-       <para>
-        Returns the <quote>filenode</quote> number currently assigned to the
-        specified relation.  The filenode is the base component of the file
-        name(s) used for the relation (see
-        <xref linkend="storage-file-layout"/> for more information).
-        For most relations the result is the same as
-        <structname>pg_class</structname>.<structfield>relfilenode</structfield>,
-        but for certain system catalogs <structfield>relfilenode</structfield>
-        is zero and this function must be used to get the correct value.  The
-        function returns NULL if passed a relation that does not have storage,
-        such as a view.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_relation_filepath</primary>
-        </indexterm>
-        <function>pg_relation_filepath</function> ( <parameter>relation</parameter> <type>regclass</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the entire file path name (relative to the database cluster's
-        data directory, <varname>PGDATA</varname>) of the relation.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_filenode_relation</primary>
-        </indexterm>
-        <function>pg_filenode_relation</function> ( <parameter>tablespace</parameter> <type>oid</type>, <parameter>filenode</parameter> <type>oid</type> )
-        <returnvalue>regclass</returnvalue>
-       </para>
-       <para>
-        Returns a relation's OID given the tablespace OID and filenode it is
-        stored under.  This is essentially the inverse mapping of
-        <function>pg_relation_filepath</function>.  For a relation in the
-        database's default tablespace, the tablespace can be specified as zero.
-        Returns <literal>NULL</literal> if no relation in the current database
-        is associated with the given values.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    <xref linkend="functions-admin-collation"/> lists functions used to manage
-    collations.
-   </para>
-
-   <table id="functions-admin-collation">
-    <title>Collation Management Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_collation_actual_version</primary>
-        </indexterm>
-        <function>pg_collation_actual_version</function> ( <type>oid</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the actual version of the collation object as it is currently
-        installed in the operating system.  If this is different from the
-        value in
-        <structname>pg_collation</structname>.<structfield>collversion</structfield>,
-        then objects depending on the collation might need to be rebuilt.  See
-        also <xref linkend="sql-altercollation"/>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_database_collation_actual_version</primary>
-        </indexterm>
-        <function>pg_database_collation_actual_version</function> ( <type>oid</type> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns the actual version of the database's collation as it is currently
-        installed in the operating system.  If this is different from the
-        value in
-        <structname>pg_database</structname>.<structfield>datcollversion</structfield>,
-        then objects depending on the collation might need to be rebuilt.  See
-        also <xref linkend="sql-alterdatabase"/>.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_import_system_collations</primary>
-        </indexterm>
-        <function>pg_import_system_collations</function> ( <parameter>schema</parameter> <type>regnamespace</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Adds collations to the system
-        catalog <structname>pg_collation</structname> based on all the locales
-        it finds in the operating system.  This is
-        what <command>initdb</command> uses; see
-        <xref linkend="collation-managing"/> for more details.  If additional
-        locales are installed into the operating system later on, this
-        function can be run again to add collations for the new locales.
-        Locales that match existing entries
-        in <structname>pg_collation</structname> will be skipped.  (But
-        collation objects based on locales that are no longer present in the
-        operating system are not removed by this function.)
-        The <parameter>schema</parameter> parameter would typically
-        be <literal>pg_catalog</literal>, but that is not a requirement; the
-        collations could be installed into some other schema as well.  The
-        function returns the number of new collation objects it created.
-        Use of this function is restricted to superusers.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    <xref linkend="functions-admin-statsmod"/> lists functions used to
-    manipulate statistics.
-    These functions cannot be executed during recovery.
-    <warning>
-     <para>
-      Changes made by these statistics manipulation functions are likely to be
-      overwritten by <link linkend="autovacuum">autovacuum</link> (or manual
-      <command>VACUUM</command> or <command>ANALYZE</command>) and should be
-      considered temporary.
-     </para>
-    </warning>
-   </para>
-
-   <table id="functions-admin-statsmod">
-    <title>Database Object Statistics Manipulation Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_restore_relation_stats</primary>
-        </indexterm>
-        <function>pg_restore_relation_stats</function> (
-        <literal>VARIADIC</literal> <parameter>kwargs</parameter> <type>"any"</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-        <para>
-         Updates table-level statistics.  Ordinarily, these statistics are
-         collected automatically or updated as a part of <xref
-         linkend="sql-vacuum"/> or <xref linkend="sql-analyze"/>, so it's not
-         necessary to call this function.  However, it is useful after a
-         restore to enable the optimizer to choose better plans if
-         <command>ANALYZE</command> has not been run yet.
-        </para>
-        <para>
-         The tracked statistics may change from version to version, so
-         arguments are passed as pairs of <replaceable>argname</replaceable>
-         and <replaceable>argvalue</replaceable> in the form:
-<programlisting>
-SELECT pg_restore_relation_stats(
-    '<replaceable>arg1name</replaceable>', '<replaceable>arg1value</replaceable>'::<replaceable>arg1type</replaceable>,
-    '<replaceable>arg2name</replaceable>', '<replaceable>arg2value</replaceable>'::<replaceable>arg2type</replaceable>,
-    '<replaceable>arg3name</replaceable>', '<replaceable>arg3value</replaceable>'::<replaceable>arg3type</replaceable>);
-</programlisting>
-        </para>
-        <para>
-         For example, to set the <structfield>relpages</structfield> and
-         <structfield>reltuples</structfield> values for the table
-         <structname>mytable</structname>:
-<programlisting>
-SELECT pg_restore_relation_stats(
-    'schemaname', 'myschema',
-    'relname',    'mytable',
-    'relpages',   173::integer,
-    'reltuples',  10000::real);
-</programlisting>
-        </para>
-        <para>
-         The arguments <literal>schemaname</literal> and
-         <literal>relname</literal> are required, and specify the table. Other
-         arguments are the names and values of statistics corresponding to
-         certain columns in <link
-         linkend="catalog-pg-class"><structname>pg_class</structname></link>.
-         The currently-supported relation statistics are
-         <literal>relpages</literal> with a value of type
-         <type>integer</type>, <literal>reltuples</literal> with a value of
-         type <type>real</type>, <literal>relallvisible</literal> with a value
-         of type <type>integer</type>, and <literal>relallfrozen</literal>
-         with a value of type <type>integer</type>.
-        </para>
-        <para>
-         Additionally, this function accepts argument name
-         <literal>version</literal> of type <type>integer</type>, which
-         specifies the server version from which the statistics originated.
-         This is anticipated to be helpful in porting statistics from older
-         versions of <productname>PostgreSQL</productname>.
-        </para>
-        <para>
-         Minor errors are reported as a <literal>WARNING</literal> and
-         ignored, and remaining statistics will still be restored. If all
-         specified statistics are successfully restored, returns
-         <literal>true</literal>, otherwise <literal>false</literal>.
-        </para>
-        <para>
-         The caller must have the <literal>MAINTAIN</literal> privilege on the
-         table or be the owner of the database.
-        </para>
-       </entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry">
-        <para role="func_signature">
-         <indexterm>
-          <primary>pg_clear_relation_stats</primary>
-         </indexterm>
-         <function>pg_clear_relation_stats</function> ( <parameter>schemaname</parameter> <type>text</type>, <parameter>relname</parameter> <type>text</type> )
-         <returnvalue>void</returnvalue>
-        </para>
-        <para>
-         Clears table-level statistics for the given relation, as though the
-         table was newly created.
-        </para>
-        <para>
-         The caller must have the <literal>MAINTAIN</literal> privilege on the
-         table or be the owner of the database.
-        </para>
-       </entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_restore_attribute_stats</primary>
-        </indexterm>
-        <function>pg_restore_attribute_stats</function> (
-        <literal>VARIADIC</literal> <parameter>kwargs</parameter> <type>"any"</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-        <para>
-         Creates or updates column-level statistics.  Ordinarily, these
-         statistics are collected automatically or updated as a part of <xref
-         linkend="sql-vacuum"/> or <xref linkend="sql-analyze"/>, so it's not
-         necessary to call this function.  However, it is useful after a
-         restore to enable the optimizer to choose better plans if
-         <command>ANALYZE</command> has not been run yet.
-        </para>
-        <para>
-         The tracked statistics may change from version to version, so
-         arguments are passed as pairs of <replaceable>argname</replaceable>
-         and <replaceable>argvalue</replaceable> in the form:
-<programlisting>
-SELECT pg_restore_attribute_stats(
-    '<replaceable>arg1name</replaceable>', '<replaceable>arg1value</replaceable>'::<replaceable>arg1type</replaceable>,
-    '<replaceable>arg2name</replaceable>', '<replaceable>arg2value</replaceable>'::<replaceable>arg2type</replaceable>,
-    '<replaceable>arg3name</replaceable>', '<replaceable>arg3value</replaceable>'::<replaceable>arg3type</replaceable>);
-</programlisting>
-        </para>
-        <para>
-         For example, to set the <structfield>avg_width</structfield> and
-         <structfield>null_frac</structfield> values for the attribute
-         <structfield>col1</structfield> of the table
-         <structname>mytable</structname>:
-<programlisting>
-SELECT pg_restore_attribute_stats(
-    'schemaname', 'myschema',
-    'relname',    'mytable',
-    'attname',    'col1',
-    'inherited',  false,
-    'avg_width',  125::integer,
-    'null_frac',  0.5::real);
-</programlisting>
-        </para>
-        <para>
-         The required arguments are <literal>schemaname</literal> and
-         <literal>relname</literal> with a value of type <type>text</type>
-         which specify the table; either <literal>attname</literal> with a
-         value of type <type>text</type> or <literal>attnum</literal> with a
-         value of type <type>smallint</type>, which specifies the column; and
-         <literal>inherited</literal>, which specifies whether the statistics
-         include values from child tables.  Other arguments are the names and
-         values of statistics corresponding to columns in <link
-         linkend="view-pg-stats"><structname>pg_stats</structname></link>.
-        </para>
-        <para>
-         Additionally, this function accepts argument name
-         <literal>version</literal> of type <type>integer</type>, which
-         specifies the server version from which the statistics originated.
-         This is anticipated to be helpful in porting statistics from older
-         versions of <productname>PostgreSQL</productname>.
-        </para>
-        <para>
-         Minor errors are reported as a <literal>WARNING</literal> and
-         ignored, and remaining statistics will still be restored. If all
-         specified statistics are successfully restored, returns
-         <literal>true</literal>, otherwise <literal>false</literal>.
-        </para>
-        <para>
-         The caller must have the <literal>MAINTAIN</literal> privilege on the
-         table or be the owner of the database.
-        </para>
-       </entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry">
-        <para role="func_signature">
-         <indexterm>
-          <primary>pg_clear_attribute_stats</primary>
-         </indexterm>
-         <function>pg_clear_attribute_stats</function> (
-         <parameter>schemaname</parameter> <type>text</type>,
-         <parameter>relname</parameter> <type>text</type>,
-         <parameter>attname</parameter> <type>text</type>,
-         <parameter>inherited</parameter> <type>boolean</type> )
-         <returnvalue>void</returnvalue>
-        </para>
-        <para>
-         Clears column-level statistics for the given relation and
-         attribute, as though the table was newly created.
-        </para>
-        <para>
-         The caller must have the <literal>MAINTAIN</literal> privilege on
-         the table or be the owner of the database.
-        </para>
-       </entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    <xref linkend="functions-info-partition"/> lists functions that provide
-    information about the structure of partitioned tables.
-   </para>
-
-   <table id="functions-info-partition">
-    <title>Partitioning Information Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_partition_tree</primary>
-        </indexterm>
-        <function>pg_partition_tree</function> ( <type>regclass</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>relid</parameter> <type>regclass</type>,
-        <parameter>parentrelid</parameter> <type>regclass</type>,
-        <parameter>isleaf</parameter> <type>boolean</type>,
-        <parameter>level</parameter> <type>integer</type> )
-       </para>
-       <para>
-        Lists the tables or indexes in the partition tree of the
-        given partitioned table or partitioned index, with one row for each
-        partition.  Information provided includes the OID of the partition,
-        the OID of its immediate parent, a boolean value telling if the
-        partition is a leaf, and an integer telling its level in the hierarchy.
-        The level value is 0 for the input table or index, 1 for its
-        immediate child partitions, 2 for their partitions, and so on.
-        Returns no rows if the relation does not exist or is not a partition
-        or partitioned table.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_partition_ancestors</primary>
-        </indexterm>
-        <function>pg_partition_ancestors</function> ( <type>regclass</type> )
-        <returnvalue>setof regclass</returnvalue>
-       </para>
-       <para>
-        Lists the ancestor relations of the given partition,
-        including the relation itself.  Returns no rows if the relation
-        does not exist or is not a partition or partitioned table.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_partition_root</primary>
-        </indexterm>
-        <function>pg_partition_root</function> ( <type>regclass</type> )
-        <returnvalue>regclass</returnvalue>
-       </para>
-       <para>
-        Returns the top-most parent of the partition tree to which the given
-        relation belongs.  Returns <literal>NULL</literal> if the relation
-        does not exist or is not a partition or partitioned table.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    For example, to check the total size of the data contained in a
-    partitioned table <structname>measurement</structname>, one could use the
-    following query:
-<programlisting>
-SELECT pg_size_pretty(sum(pg_relation_size(relid))) AS total_size
-  FROM pg_partition_tree('measurement');
-</programlisting>
-   </para>
-
-  </sect2>
-
-  <sect2 id="functions-admin-index">
-   <title>Index Maintenance Functions</title>
-
-   <para>
-    <xref linkend="functions-admin-index-table"/> shows the functions
-    available for index maintenance tasks.  (Note that these maintenance
-    tasks are normally done automatically by autovacuum; use of these
-    functions is only required in special cases.)
-    These functions cannot be executed during recovery.
-    Use of these functions is restricted to superusers and the owner
-    of the given index.
-   </para>
-
-   <table id="functions-admin-index-table">
-    <title>Index Maintenance Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>brin_summarize_new_values</primary>
-        </indexterm>
-        <function>brin_summarize_new_values</function> ( <parameter>index</parameter> <type>regclass</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Scans the specified BRIN index to find page ranges in the base table
-        that are not currently summarized by the index; for any such range it
-        creates a new summary index tuple by scanning those table pages.
-        Returns the number of new page range summaries that were inserted
-        into the index.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>brin_summarize_range</primary>
-        </indexterm>
-        <function>brin_summarize_range</function> ( <parameter>index</parameter> <type>regclass</type>, <parameter>blockNumber</parameter> <type>bigint</type> )
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Summarizes the page range covering the given block, if not already
-        summarized.  This is
-        like <function>brin_summarize_new_values</function> except that it
-        only processes the page range that covers the given table block number.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>brin_desummarize_range</primary>
-        </indexterm>
-        <function>brin_desummarize_range</function> ( <parameter>index</parameter> <type>regclass</type>, <parameter>blockNumber</parameter> <type>bigint</type> )
-        <returnvalue>void</returnvalue>
-       </para>
-       <para>
-        Removes the BRIN index tuple that summarizes the page range covering
-        the given table block, if there is one.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>gin_clean_pending_list</primary>
-        </indexterm>
-        <function>gin_clean_pending_list</function> ( <parameter>index</parameter> <type>regclass</type> )
-        <returnvalue>bigint</returnvalue>
-       </para>
-       <para>
-        Cleans up the <quote>pending</quote> list of the specified GIN index
-        by moving entries in it, in bulk, to the main GIN data structure.
-        Returns the number of pages removed from the pending list.
-        If the argument is a GIN index built with
-        the <literal>fastupdate</literal> option disabled, no cleanup happens
-        and the result is zero, because the index doesn't have a pending list.
-        See <xref linkend="gin-fast-update"/> and <xref linkend="gin-tips"/>
-        for details about the pending list and <literal>fastupdate</literal>
-        option.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  </sect2>
-
-  <sect2 id="functions-admin-genfile">
-   <title>Generic File Access Functions</title>
-
-   <para>
-    The functions shown in <xref
-    linkend="functions-admin-genfile-table"/> provide native access to
-    files on the machine hosting the server. Only files within the
-    database cluster directory and the <varname>log_directory</varname> can be
-    accessed, unless the user is a superuser or is granted the role
-    <literal>pg_read_server_files</literal>.  Use a relative path for files in
-    the cluster directory, and a path matching the <varname>log_directory</varname>
-    configuration setting for log files.
-   </para>
-
-   <para>
-    Note that granting users the EXECUTE privilege on
-    <function>pg_read_file()</function>, or related functions, allows them the
-    ability to read any file on the server that the database server process can
-    read; these functions bypass all in-database privilege checks.  This means
-    that, for example, a user with such access is able to read the contents of
-    the <structname>pg_authid</structname> table where authentication
-    information is stored, as well as read any table data in the database.
-    Therefore, granting access to these functions should be carefully
-    considered.
-   </para>
-
-   <para>
-    When granting privilege on these functions, note that the table entries
-    showing optional parameters are mostly implemented as several physical
-    functions with different parameter lists.  Privilege must be granted
-    separately on each such function, if it is to be
-    used.  <application>psql</application>'s <command>\df</command> command
-    can be useful to check what the actual function signatures are.
-   </para>
-
-   <para>
-    Some of these functions take an optional <parameter>missing_ok</parameter>
-    parameter, which specifies the behavior when the file or directory does
-    not exist.  If <literal>true</literal>, the function
-    returns <literal>NULL</literal> or an empty result set, as appropriate.
-    If <literal>false</literal>, an error is raised.  (Failure conditions
-    other than <quote>file not found</quote> are reported as errors in any
-    case.)  The default is <literal>false</literal>.
-   </para>
-
-   <table id="functions-admin-genfile-table">
-    <title>Generic File Access Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_ls_dir</primary>
-        </indexterm>
-        <function>pg_ls_dir</function> ( <parameter>dirname</parameter> <type>text</type> <optional>, <parameter>missing_ok</parameter> <type>boolean</type>, <parameter>include_dot_dirs</parameter> <type>boolean</type> </optional> )
-        <returnvalue>setof text</returnvalue>
-       </para>
-       <para>
-        Returns the names of all files (and directories and other special
-        files) in the specified
-        directory. The <parameter>include_dot_dirs</parameter> parameter
-        indicates whether <quote>.</quote> and <quote>..</quote> are to be
-        included in the result set; the default is to exclude them.  Including
-        them can be useful when <parameter>missing_ok</parameter>
-        is <literal>true</literal>, to distinguish an empty directory from a
-        non-existent directory.
-       </para>
-       <para>
-        This function is restricted to superusers by default, but other users
-        can be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_ls_logdir</primary>
-        </indexterm>
-        <function>pg_ls_logdir</function> ()
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>name</parameter> <type>text</type>,
-        <parameter>size</parameter> <type>bigint</type>,
-        <parameter>modification</parameter> <type>timestamp with time zone</type> )
-       </para>
-       <para>
-        Returns the name, size, and last modification time (mtime) of each
-        ordinary file in the server's log directory.  Filenames beginning with
-        a dot, directories, and other special files are excluded.
-       </para>
-       <para>
-        This function is restricted to superusers and roles with privileges of
-        the <literal>pg_monitor</literal> role by default, but other users can
-        be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_ls_waldir</primary>
-        </indexterm>
-        <function>pg_ls_waldir</function> ()
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>name</parameter> <type>text</type>,
-        <parameter>size</parameter> <type>bigint</type>,
-        <parameter>modification</parameter> <type>timestamp with time zone</type> )
-       </para>
-       <para>
-        Returns the name, size, and last modification time (mtime) of each
-        ordinary file in the server's write-ahead log (WAL) directory.
-        Filenames beginning with a dot, directories, and other special files
-        are excluded.
-       </para>
-       <para>
-        This function is restricted to superusers and roles with privileges of
-        the <literal>pg_monitor</literal> role by default, but other users can
-        be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_ls_logicalmapdir</primary>
-        </indexterm>
-        <function>pg_ls_logicalmapdir</function> ()
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>name</parameter> <type>text</type>,
-        <parameter>size</parameter> <type>bigint</type>,
-        <parameter>modification</parameter> <type>timestamp with time zone</type> )
-       </para>
-       <para>
-        Returns the name, size, and last modification time (mtime) of each
-        ordinary file in the server's <filename>pg_logical/mappings</filename>
-        directory. Filenames beginning with a dot, directories, and other
-        special files are excluded.
-       </para>
-       <para>
-        This function is restricted to superusers and members of
-        the <literal>pg_monitor</literal> role by default, but other users can
-        be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_ls_logicalsnapdir</primary>
-        </indexterm>
-        <function>pg_ls_logicalsnapdir</function> ()
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>name</parameter> <type>text</type>,
-        <parameter>size</parameter> <type>bigint</type>,
-        <parameter>modification</parameter> <type>timestamp with time zone</type> )
-       </para>
-       <para>
-        Returns the name, size, and last modification time (mtime) of each
-        ordinary file in the server's <filename>pg_logical/snapshots</filename>
-        directory. Filenames beginning with a dot, directories, and other
-        special files are excluded.
-       </para>
-       <para>
-        This function is restricted to superusers and members of
-        the <literal>pg_monitor</literal> role by default, but other users can
-        be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_ls_replslotdir</primary>
-        </indexterm>
-        <function>pg_ls_replslotdir</function> ( <parameter>slot_name</parameter> <type>text</type> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>name</parameter> <type>text</type>,
-        <parameter>size</parameter> <type>bigint</type>,
-        <parameter>modification</parameter> <type>timestamp with time zone</type> )
-       </para>
-       <para>
-        Returns the name, size, and last modification time (mtime) of each
-        ordinary file in the server's <filename>pg_replslot/slot_name</filename>
-        directory, where <parameter>slot_name</parameter> is the name of the
-        replication slot provided as input of the function. Filenames beginning
-        with a dot, directories, and other special files are excluded.
-       </para>
-       <para>
-        This function is restricted to superusers and members of
-        the <literal>pg_monitor</literal> role by default, but other users can
-        be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_ls_summariesdir</primary>
-        </indexterm>
-        <function>pg_ls_summariesdir</function> ()
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>name</parameter> <type>text</type>,
-        <parameter>size</parameter> <type>bigint</type>,
-        <parameter>modification</parameter> <type>timestamp with time zone</type> )
-       </para>
-       <para>
-        Returns the name, size, and last modification time (mtime) of each
-        ordinary file in the server's WAL summaries directory
-        (<filename>pg_wal/summaries</filename>).  Filenames beginning
-        with a dot, directories, and other special files are excluded.
-       </para>
-       <para>
-        This function is restricted to superusers and members of
-        the <literal>pg_monitor</literal> role by default, but other users can
-        be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_ls_archive_statusdir</primary>
-        </indexterm>
-        <function>pg_ls_archive_statusdir</function> ()
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>name</parameter> <type>text</type>,
-        <parameter>size</parameter> <type>bigint</type>,
-        <parameter>modification</parameter> <type>timestamp with time zone</type> )
-       </para>
-       <para>
-        Returns the name, size, and last modification time (mtime) of each
-        ordinary file in the server's WAL archive status directory
-        (<filename>pg_wal/archive_status</filename>).  Filenames beginning
-        with a dot, directories, and other special files are excluded.
-       </para>
-       <para>
-        This function is restricted to superusers and members of
-        the <literal>pg_monitor</literal> role by default, but other users can
-        be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-
-        <indexterm>
-         <primary>pg_ls_tmpdir</primary>
-        </indexterm>
-        <function>pg_ls_tmpdir</function> ( <optional> <parameter>tablespace</parameter> <type>oid</type> </optional> )
-        <returnvalue>setof record</returnvalue>
-        ( <parameter>name</parameter> <type>text</type>,
-        <parameter>size</parameter> <type>bigint</type>,
-        <parameter>modification</parameter> <type>timestamp with time zone</type> )
-       </para>
-       <para>
-        Returns the name, size, and last modification time (mtime) of each
-        ordinary file in the temporary file directory for the
-        specified <parameter>tablespace</parameter>.
-        If <parameter>tablespace</parameter> is not provided,
-        the <literal>pg_default</literal> tablespace is examined.  Filenames
-        beginning with a dot, directories, and other special files are
-        excluded.
-       </para>
-       <para>
-        This function is restricted to superusers and members of
-        the <literal>pg_monitor</literal> role by default, but other users can
-        be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_read_file</primary>
-        </indexterm>
-        <function>pg_read_file</function> ( <parameter>filename</parameter> <type>text</type> <optional>, <parameter>offset</parameter> <type>bigint</type>, <parameter>length</parameter> <type>bigint</type> </optional> <optional>, <parameter>missing_ok</parameter> <type>boolean</type> </optional> )
-        <returnvalue>text</returnvalue>
-       </para>
-       <para>
-        Returns all or part of a text file, starting at the
-        given byte <parameter>offset</parameter>, returning at
-        most <parameter>length</parameter> bytes (less if the end of file is
-        reached first).  If <parameter>offset</parameter> is negative, it is
-        relative to the end of the file.  If <parameter>offset</parameter>
-        and <parameter>length</parameter> are omitted, the entire file is
-        returned.  The bytes read from the file are interpreted as a string in
-        the database's encoding; an error is thrown if they are not valid in
-        that encoding.
-       </para>
-       <para>
-        This function is restricted to superusers by default, but other users
-        can be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_read_binary_file</primary>
-        </indexterm>
-        <function>pg_read_binary_file</function> ( <parameter>filename</parameter> <type>text</type> <optional>, <parameter>offset</parameter> <type>bigint</type>, <parameter>length</parameter> <type>bigint</type> </optional> <optional>, <parameter>missing_ok</parameter> <type>boolean</type> </optional> )
-        <returnvalue>bytea</returnvalue>
-       </para>
-       <para>
-        Returns all or part of a file.  This function is identical to
-        <function>pg_read_file</function> except that it can read arbitrary
-        binary data, returning the result as <type>bytea</type>
-        not <type>text</type>; accordingly, no encoding checks are performed.
-       </para>
-       <para>
-        This function is restricted to superusers by default, but other users
-        can be granted EXECUTE to run the function.
-       </para>
-       <para>
-        In combination with the <function>convert_from</function> function,
-        this function can be used to read a text file in a specified encoding
-        and convert to the database's encoding:
-<programlisting>
-SELECT convert_from(pg_read_binary_file('file_in_utf8.txt'), 'UTF8');
-</programlisting>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_stat_file</primary>
-        </indexterm>
-        <function>pg_stat_file</function> ( <parameter>filename</parameter> <type>text</type> <optional>, <parameter>missing_ok</parameter> <type>boolean</type> </optional> )
-        <returnvalue>record</returnvalue>
-        ( <parameter>size</parameter> <type>bigint</type>,
-        <parameter>access</parameter> <type>timestamp with time zone</type>,
-        <parameter>modification</parameter> <type>timestamp with time zone</type>,
-        <parameter>change</parameter> <type>timestamp with time zone</type>,
-        <parameter>creation</parameter> <type>timestamp with time zone</type>,
-        <parameter>isdir</parameter> <type>boolean</type> )
-       </para>
-       <para>
-        Returns a record containing the file's size, last access time stamp,
-        last modification time stamp, last file status change time stamp (Unix
-        platforms only), file creation time stamp (Windows only), and a flag
-        indicating if it is a directory.
-       </para>
-       <para>
-        This function is restricted to superusers by default, but other users
-        can be granted EXECUTE to run the function.
-       </para></entry>
-      </row>
-
-     </tbody>
-    </tgroup>
-   </table>
-
-  </sect2>
-
-  <sect2 id="functions-advisory-locks">
-   <title>Advisory Lock Functions</title>
-
-   <para>
-    The functions shown in <xref linkend="functions-advisory-locks-table"/>
-    manage advisory locks.  For details about proper use of these functions,
-    see <xref linkend="advisory-locks"/>.
-   </para>
-
-   <para>
-    All these functions are intended to be used to lock application-defined
-    resources, which can be identified either by a single 64-bit key value or
-    two 32-bit key values (note that these two key spaces do not overlap).
-    If another session already holds a conflicting lock on the same resource
-    identifier, the functions will either wait until the resource becomes
-    available, or return a <literal>false</literal> result, as appropriate for
-    the function.
-    Locks can be either shared or exclusive: a shared lock does not conflict
-    with other shared locks on the same resource, only with exclusive locks.
-    Locks can be taken at session level (so that they are held until released
-    or the session ends) or at transaction level (so that they are held until
-    the current transaction ends; there is no provision for manual release).
-    Multiple session-level lock requests stack, so that if the same resource
-    identifier is locked three times there must then be three unlock requests
-    to release the resource in advance of session end.
-   </para>
-
-   <table id="functions-advisory-locks-table">
-    <title>Advisory Lock Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_advisory_lock</primary>
-        </indexterm>
-        <function>pg_advisory_lock</function> ( <parameter>key</parameter> <type>bigint</type> )
-        <returnvalue>void</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>pg_advisory_lock</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
-        <returnvalue>void</returnvalue>
-       </para>
-       <para>
-        Obtains an exclusive session-level advisory lock, waiting if necessary.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_advisory_lock_shared</primary>
-        </indexterm>
-        <function>pg_advisory_lock_shared</function> ( <parameter>key</parameter> <type>bigint</type> )
-        <returnvalue>void</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>pg_advisory_lock_shared</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
-        <returnvalue>void</returnvalue>
-       </para>
-       <para>
-        Obtains a shared session-level advisory lock, waiting if necessary.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_advisory_unlock</primary>
-        </indexterm>
-        <function>pg_advisory_unlock</function> ( <parameter>key</parameter> <type>bigint</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>pg_advisory_unlock</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Releases a previously-acquired exclusive session-level advisory lock.
-        Returns <literal>true</literal> if the lock is successfully released.
-        If the lock was not held, <literal>false</literal> is returned, and in
-        addition, an SQL warning will be reported by the server.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_advisory_unlock_all</primary>
-        </indexterm>
-        <function>pg_advisory_unlock_all</function> ()
-        <returnvalue>void</returnvalue>
-       </para>
-       <para>
-        Releases all session-level advisory locks held by the current session.
-        (This function is implicitly invoked at session end, even if the
-        client disconnects ungracefully.)
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_advisory_unlock_shared</primary>
-        </indexterm>
-        <function>pg_advisory_unlock_shared</function> ( <parameter>key</parameter> <type>bigint</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>pg_advisory_unlock_shared</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Releases a previously-acquired shared session-level advisory lock.
-        Returns <literal>true</literal> if the lock is successfully released.
-        If the lock was not held, <literal>false</literal> is returned, and in
-        addition, an SQL warning will be reported by the server.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_advisory_xact_lock</primary>
-        </indexterm>
-        <function>pg_advisory_xact_lock</function> ( <parameter>key</parameter> <type>bigint</type> )
-        <returnvalue>void</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>pg_advisory_xact_lock</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
-        <returnvalue>void</returnvalue>
-       </para>
-       <para>
-        Obtains an exclusive transaction-level advisory lock, waiting if
-        necessary.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_advisory_xact_lock_shared</primary>
-        </indexterm>
-        <function>pg_advisory_xact_lock_shared</function> ( <parameter>key</parameter> <type>bigint</type> )
-        <returnvalue>void</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>pg_advisory_xact_lock_shared</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
-        <returnvalue>void</returnvalue>
-       </para>
-       <para>
-        Obtains a shared transaction-level advisory lock, waiting if
-        necessary.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_try_advisory_lock</primary>
-        </indexterm>
-        <function>pg_try_advisory_lock</function> ( <parameter>key</parameter> <type>bigint</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>pg_try_advisory_lock</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Obtains an exclusive session-level advisory lock if available.
-        This will either obtain the lock immediately and
-        return <literal>true</literal>, or return <literal>false</literal>
-        without waiting if the lock cannot be acquired immediately.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_try_advisory_lock_shared</primary>
-        </indexterm>
-        <function>pg_try_advisory_lock_shared</function> ( <parameter>key</parameter> <type>bigint</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>pg_try_advisory_lock_shared</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Obtains a shared session-level advisory lock if available.
-        This will either obtain the lock immediately and
-        return <literal>true</literal>, or return <literal>false</literal>
-        without waiting if the lock cannot be acquired immediately.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_try_advisory_xact_lock</primary>
-        </indexterm>
-        <function>pg_try_advisory_xact_lock</function> ( <parameter>key</parameter> <type>bigint</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>pg_try_advisory_xact_lock</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Obtains an exclusive transaction-level advisory lock if available.
-        This will either obtain the lock immediately and
-        return <literal>true</literal>, or return <literal>false</literal>
-        without waiting if the lock cannot be acquired immediately.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_try_advisory_xact_lock_shared</primary>
-        </indexterm>
-        <function>pg_try_advisory_xact_lock_shared</function> ( <parameter>key</parameter> <type>bigint</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para role="func_signature">
-        <function>pg_try_advisory_xact_lock_shared</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
-        <returnvalue>boolean</returnvalue>
-       </para>
-       <para>
-        Obtains a shared transaction-level advisory lock if available.
-        This will either obtain the lock immediately and
-        return <literal>true</literal>, or return <literal>false</literal>
-        without waiting if the lock cannot be acquired immediately.
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-  </sect2>
-
-  </sect1>
-
-  <sect1 id="functions-trigger">
-   <title>Trigger Functions</title>
-
-  <para>
-   While many uses of triggers involve user-written trigger functions,
-   <productname>PostgreSQL</productname> provides a few built-in trigger
-   functions that can be used directly in user-defined triggers.  These
-   are summarized in <xref linkend="builtin-triggers-table"/>.
-   (Additional built-in trigger functions exist, which implement foreign
-   key constraints and deferred index constraints.  Those are not documented
-   here since users need not use them directly.)
-  </para>
-
-  <para>
-   For more information about creating triggers, see
-   <xref linkend="sql-createtrigger"/>.
-  </para>
-
-   <table id="builtin-triggers-table">
-    <title>Built-In Trigger Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para>
-       <para>
-        Example Usage
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-       <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>suppress_redundant_updates_trigger</primary>
-        </indexterm>
-        <function>suppress_redundant_updates_trigger</function> ( )
-        <returnvalue>trigger</returnvalue>
-       </para>
-       <para>
-        Suppresses do-nothing update operations.  See below for details.
-       </para>
-       <para>
-        <literal>CREATE TRIGGER ... suppress_redundant_updates_trigger()</literal>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>tsvector_update_trigger</primary>
-        </indexterm>
-        <function>tsvector_update_trigger</function> ( )
-        <returnvalue>trigger</returnvalue>
-       </para>
-       <para>
-        Automatically updates a <type>tsvector</type> column from associated
-        plain-text document column(s).  The text search configuration to use
-        is specified by name as a trigger argument.  See
-        <xref linkend="textsearch-update-triggers"/> for details.
-       </para>
-       <para>
-        <literal>CREATE TRIGGER ... tsvector_update_trigger(tsvcol, 'pg_catalog.swedish', title, body)</literal>
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>tsvector_update_trigger_column</primary>
-        </indexterm>
-        <function>tsvector_update_trigger_column</function> ( )
-        <returnvalue>trigger</returnvalue>
-       </para>
-       <para>
-        Automatically updates a <type>tsvector</type> column from associated
-        plain-text document column(s).  The text search configuration to use
-        is taken from a <type>regconfig</type> column of the table.  See
-        <xref linkend="textsearch-update-triggers"/> for details.
-       </para>
-       <para>
-        <literal>CREATE TRIGGER ... tsvector_update_trigger_column(tsvcol, tsconfigcol, title, body)</literal>
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-      The <function>suppress_redundant_updates_trigger</function> function,
-      when applied as a row-level <literal>BEFORE UPDATE</literal> trigger,
-      will prevent any update that does not actually change the data in the
-      row from taking place.  This overrides the normal behavior which always
-      performs a physical row update
-      regardless of whether or not the data has changed. (This normal behavior
-      makes updates run faster, since no checking is required, and is also
-      useful in certain cases.)
-    </para>
-
-    <para>
-      Ideally, you should avoid running updates that don't actually
-      change the data in the record. Redundant updates can cost considerable
-      unnecessary time, especially if there are lots of indexes to alter,
-      and space in dead rows that will eventually have to be vacuumed.
-      However, detecting such situations in client code is not
-      always easy, or even possible, and writing expressions to detect
-      them can be error-prone. An alternative is to use
-      <function>suppress_redundant_updates_trigger</function>, which will skip
-      updates that don't change the data. You should use this with care,
-      however. The trigger takes a small but non-trivial time for each record,
-      so if most of the records affected by updates do actually change,
-      use of this trigger will make updates run slower on average.
-    </para>
-
-    <para>
-      The <function>suppress_redundant_updates_trigger</function> function can be
-      added to a table like this:
-<programlisting>
-CREATE TRIGGER z_min_update
-BEFORE UPDATE ON tablename
-FOR EACH ROW EXECUTE FUNCTION suppress_redundant_updates_trigger();
-</programlisting>
-      In most cases, you need to fire this trigger last for each row, so that
-      it does not override other triggers that might wish to alter the row.
-      Bearing in mind that triggers fire in name order, you would therefore
-      choose a trigger name that comes after the name of any other trigger
-      you might have on the table.  (Hence the <quote>z</quote> prefix in the
-      example.)
-    </para>
-  </sect1>
-
-  <sect1 id="functions-event-triggers">
-   <title>Event Trigger Functions</title>
-
-   <para>
-    <productname>PostgreSQL</productname> provides these helper functions
-    to retrieve information from event triggers.
-   </para>
-
-   <para>
-    For more information about event triggers,
-    see <xref linkend="event-triggers"/>.
-   </para>
-
-  <sect2 id="pg-event-trigger-ddl-command-end-functions">
-   <title>Capturing Changes at Command End</title>
-
-   <indexterm>
-    <primary>pg_event_trigger_ddl_commands</primary>
-   </indexterm>
-
-<synopsis>
-<function>pg_event_trigger_ddl_commands</function> () <returnvalue>setof record</returnvalue>
-</synopsis>
-
-   <para>
-    <function>pg_event_trigger_ddl_commands</function> returns a list of
-    <acronym>DDL</acronym> commands executed by each user action,
-    when invoked in a function attached to a
-    <literal>ddl_command_end</literal> event trigger.  If called in any other
-    context, an error is raised.
-    <function>pg_event_trigger_ddl_commands</function> returns one row for each
-    base command executed; some commands that are a single SQL sentence
-    may return more than one row.  This function returns the following
-    columns:
-
-    <informaltable>
-     <tgroup cols="3">
-      <thead>
-       <row>
-        <entry>Name</entry>
-        <entry>Type</entry>
-        <entry>Description</entry>
-       </row>
-      </thead>
-
-      <tbody>
-       <row>
-        <entry><literal>classid</literal></entry>
-        <entry><type>oid</type></entry>
-        <entry>OID of catalog the object belongs in</entry>
-       </row>
-       <row>
-        <entry><literal>objid</literal></entry>
-        <entry><type>oid</type></entry>
-        <entry>OID of the object itself</entry>
-       </row>
-       <row>
-        <entry><literal>objsubid</literal></entry>
-        <entry><type>integer</type></entry>
-        <entry>Sub-object ID (e.g., attribute number for a column)</entry>
-       </row>
-       <row>
-        <entry><literal>command_tag</literal></entry>
-        <entry><type>text</type></entry>
-        <entry>Command tag</entry>
-       </row>
-       <row>
-        <entry><literal>object_type</literal></entry>
-        <entry><type>text</type></entry>
-        <entry>Type of the object</entry>
-       </row>
-       <row>
-        <entry><literal>schema_name</literal></entry>
-        <entry><type>text</type></entry>
-        <entry>
-         Name of the schema the object belongs in, if any; otherwise <literal>NULL</literal>.
-         No quoting is applied.
-        </entry>
-       </row>
-       <row>
-        <entry><literal>object_identity</literal></entry>
-        <entry><type>text</type></entry>
-        <entry>
-         Text rendering of the object identity, schema-qualified. Each
-         identifier included in the identity is quoted if necessary.
-        </entry>
-       </row>
-       <row>
-        <entry><literal>in_extension</literal></entry>
-        <entry><type>boolean</type></entry>
-        <entry>True if the command is part of an extension script</entry>
-       </row>
-       <row>
-        <entry><literal>command</literal></entry>
-        <entry><type>pg_ddl_command</type></entry>
-        <entry>
-         A complete representation of the command, in internal format.
-         This cannot be output directly, but it can be passed to other
-         functions to obtain different pieces of information about the
-         command.
-        </entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </informaltable>
-   </para>
-  </sect2>
-
-  <sect2 id="pg-event-trigger-sql-drop-functions">
-   <title>Processing Objects Dropped by a DDL Command</title>
-
-   <indexterm>
-     <primary>pg_event_trigger_dropped_objects</primary>
-   </indexterm>
-
-<synopsis>
-<function>pg_event_trigger_dropped_objects</function> () <returnvalue>setof record</returnvalue>
-</synopsis>
-
-   <para>
-    <function>pg_event_trigger_dropped_objects</function> returns a list of all objects
-    dropped by the command in whose <literal>sql_drop</literal> event it is called.
-    If called in any other context, an error is raised.
-    This function returns the following columns:
-
-    <informaltable>
-     <tgroup cols="3">
-      <thead>
-       <row>
-        <entry>Name</entry>
-        <entry>Type</entry>
-        <entry>Description</entry>
-       </row>
-      </thead>
-
-      <tbody>
-       <row>
-        <entry><literal>classid</literal></entry>
-        <entry><type>oid</type></entry>
-        <entry>OID of catalog the object belonged in</entry>
-       </row>
-       <row>
-        <entry><literal>objid</literal></entry>
-        <entry><type>oid</type></entry>
-        <entry>OID of the object itself</entry>
-       </row>
-       <row>
-        <entry><literal>objsubid</literal></entry>
-        <entry><type>integer</type></entry>
-        <entry>Sub-object ID (e.g., attribute number for a column)</entry>
-       </row>
-       <row>
-        <entry><literal>original</literal></entry>
-        <entry><type>boolean</type></entry>
-        <entry>True if this was one of the root object(s) of the deletion</entry>
-       </row>
-       <row>
-        <entry><literal>normal</literal></entry>
-        <entry><type>boolean</type></entry>
-        <entry>
-         True if there was a normal dependency relationship
-         in the dependency graph leading to this object
-        </entry>
-       </row>
-       <row>
-        <entry><literal>is_temporary</literal></entry>
-        <entry><type>boolean</type></entry>
-        <entry>
-         True if this was a temporary object
-        </entry>
-       </row>
-       <row>
-        <entry><literal>object_type</literal></entry>
-        <entry><type>text</type></entry>
-        <entry>Type of the object</entry>
-       </row>
-       <row>
-        <entry><literal>schema_name</literal></entry>
-        <entry><type>text</type></entry>
-        <entry>
-         Name of the schema the object belonged in, if any; otherwise <literal>NULL</literal>.
-         No quoting is applied.
-        </entry>
-       </row>
-       <row>
-        <entry><literal>object_name</literal></entry>
-        <entry><type>text</type></entry>
-        <entry>
-         Name of the object, if the combination of schema and name can be
-         used as a unique identifier for the object; otherwise <literal>NULL</literal>.
-         No quoting is applied, and name is never schema-qualified.
-        </entry>
-       </row>
-       <row>
-        <entry><literal>object_identity</literal></entry>
-        <entry><type>text</type></entry>
-        <entry>
-         Text rendering of the object identity, schema-qualified. Each
-         identifier included in the identity is quoted if necessary.
-        </entry>
-       </row>
-       <row>
-        <entry><literal>address_names</literal></entry>
-        <entry><type>text[]</type></entry>
-        <entry>
-         An array that, together with <literal>object_type</literal> and
-         <literal>address_args</literal>, can be used by
-         the <function>pg_get_object_address</function> function to
-         recreate the object address in a remote server containing an
-         identically named object of the same kind.
-        </entry>
-       </row>
-       <row>
-        <entry><literal>address_args</literal></entry>
-        <entry><type>text[]</type></entry>
-        <entry>
-         Complement for <literal>address_names</literal>
-        </entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </informaltable>
-   </para>
-
-   <para>
-    The <function>pg_event_trigger_dropped_objects</function> function can be used
-    in an event trigger like this:
-<programlisting>
-CREATE FUNCTION test_event_trigger_for_drops()
-        RETURNS event_trigger LANGUAGE plpgsql AS $$
-DECLARE
-    obj record;
-BEGIN
-    FOR obj IN SELECT * FROM pg_event_trigger_dropped_objects()
-    LOOP
-        RAISE NOTICE '% dropped object: % %.% %',
-                     tg_tag,
-                     obj.object_type,
-                     obj.schema_name,
-                     obj.object_name,
-                     obj.object_identity;
-    END LOOP;
-END;
-$$;
-CREATE EVENT TRIGGER test_event_trigger_for_drops
-   ON sql_drop
-   EXECUTE FUNCTION test_event_trigger_for_drops();
-</programlisting>
-    </para>
-  </sect2>
-
-  <sect2 id="pg-event-trigger-table-rewrite-functions">
-   <title>Handling a Table Rewrite Event</title>
-
-   <para>
-    The functions shown in
-    <xref linkend="functions-event-trigger-table-rewrite"/>
-    provide information about a table for which a
-    <literal>table_rewrite</literal> event has just been called.
-    If called in any other context, an error is raised.
-   </para>
-
-   <table id="functions-event-trigger-table-rewrite">
-    <title>Table Rewrite Information Functions</title>
-    <tgroup cols="1">
-     <thead>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        Function
-       </para>
-       <para>
-        Description
-       </para></entry>
-      </row>
-     </thead>
-
-     <tbody>
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_event_trigger_table_rewrite_oid</primary>
-        </indexterm>
-        <function>pg_event_trigger_table_rewrite_oid</function> ()
-        <returnvalue>oid</returnvalue>
-       </para>
-       <para>
-        Returns the OID of the table about to be rewritten.
-       </para></entry>
-      </row>
-
-      <row>
-       <entry role="func_table_entry"><para role="func_signature">
-        <indexterm>
-         <primary>pg_event_trigger_table_rewrite_reason</primary>
-        </indexterm>
-        <function>pg_event_trigger_table_rewrite_reason</function> ()
-        <returnvalue>integer</returnvalue>
-       </para>
-       <para>
-        Returns a code explaining the reason(s) for rewriting. The value is
-        a bitmap built from the following values: <literal>1</literal>
-        (the table has changed its persistence), <literal>2</literal>
-        (default value of a column has changed), <literal>4</literal>
-        (a column has a new data type) and <literal>8</literal>
-        (the table access method has changed).
-       </para></entry>
-      </row>
-     </tbody>
-    </tgroup>
-   </table>
-
-   <para>
-    These functions can be used in an event trigger like this:
-<programlisting>
-CREATE FUNCTION test_event_trigger_table_rewrite_oid()
- RETURNS event_trigger
- LANGUAGE plpgsql AS
-$$
-BEGIN
-  RAISE NOTICE 'rewriting table % for reason %',
-                pg_event_trigger_table_rewrite_oid()::regclass,
-                pg_event_trigger_table_rewrite_reason();
-END;
-$$;
-
-CREATE EVENT TRIGGER test_table_rewrite_oid
-                  ON table_rewrite
-   EXECUTE FUNCTION test_event_trigger_table_rewrite_oid();
-</programlisting>
-    </para>
-  </sect2>
-  </sect1>
-
-  <sect1 id="functions-statistics">
-   <title>Statistics Information Functions</title>
-
-   <indexterm zone="functions-statistics">
-    <primary>function</primary>
-    <secondary>statistics</secondary>
-   </indexterm>
-
-   <para>
-    <productname>PostgreSQL</productname> provides a function to inspect complex
-    statistics defined using the <command>CREATE STATISTICS</command> command.
-   </para>
-
-  <sect2 id="functions-statistics-mcv">
-   <title>Inspecting MCV Lists</title>
-
-   <indexterm>
-    <primary>pg_mcv_list_items</primary>
-   </indexterm>
-
-<synopsis>
-<function>pg_mcv_list_items</function> ( <type>pg_mcv_list</type> ) <returnvalue>setof record</returnvalue>
-</synopsis>
-
-   <para>
-    <function>pg_mcv_list_items</function> returns a set of records describing
-    all items stored in a multi-column <acronym>MCV</acronym> list.  It
-    returns the following columns:
-
-    <informaltable>
-     <tgroup cols="3">
-      <thead>
-       <row>
-        <entry>Name</entry>
-        <entry>Type</entry>
-        <entry>Description</entry>
-       </row>
-      </thead>
-
-      <tbody>
-       <row>
-        <entry><literal>index</literal></entry>
-        <entry><type>integer</type></entry>
-        <entry>index of the item in the <acronym>MCV</acronym> list</entry>
-       </row>
-       <row>
-        <entry><literal>values</literal></entry>
-        <entry><type>text[]</type></entry>
-        <entry>values stored in the MCV item</entry>
-       </row>
-       <row>
-        <entry><literal>nulls</literal></entry>
-        <entry><type>boolean[]</type></entry>
-        <entry>flags identifying <literal>NULL</literal> values</entry>
-       </row>
-       <row>
-        <entry><literal>frequency</literal></entry>
-        <entry><type>double precision</type></entry>
-        <entry>frequency of this <acronym>MCV</acronym> item</entry>
-       </row>
-       <row>
-        <entry><literal>base_frequency</literal></entry>
-        <entry><type>double precision</type></entry>
-        <entry>base frequency of this <acronym>MCV</acronym> item</entry>
-       </row>
-      </tbody>
-     </tgroup>
-    </informaltable>
-   </para>
-
-   <para>
-    The <function>pg_mcv_list_items</function> function can be used like this:
-
-<programlisting>
-SELECT m.* FROM pg_statistic_ext join pg_statistic_ext_data on (oid = stxoid),
-                pg_mcv_list_items(stxdmcv) m WHERE stxname = 'stts';
-</programlisting>
-
-    Values of the <type>pg_mcv_list</type> type can be obtained only from the
-    <structname>pg_statistic_ext_data</structname>.<structfield>stxdmcv</structfield>
-    column.
-   </para>
-  </sect2>
-
-  </sect1>
-
-</chapter>
diff --git a/doc/src/sgml/func/allfiles.sgml b/doc/src/sgml/func/allfiles.sgml
new file mode 100644
index 0000000000000..ce11ef1d5d8ed
--- /dev/null
+++ b/doc/src/sgml/func/allfiles.sgml
@@ -0,0 +1,40 @@
+<!--
+doc/src/sgml/func/allfiles.sgml
+PostgreSQL documentation
+Complete list of usable sgml source files in this directory.
+-->
+
+<!-- function references -->
+
+<!ENTITY func                       SYSTEM "func.sgml">
+<!ENTITY func-logical               SYSTEM "func-logical.sgml">
+<!ENTITY func-comparison            SYSTEM "func-comparison.sgml">
+<!ENTITY func-math                  SYSTEM "func-math.sgml">
+<!ENTITY func-string                SYSTEM "func-string.sgml">
+<!ENTITY func-binarystring          SYSTEM "func-binarystring.sgml">
+<!ENTITY func-bitstring             SYSTEM "func-bitstring.sgml">
+<!ENTITY func-matching              SYSTEM "func-matching.sgml">
+<!ENTITY func-formatting            SYSTEM "func-formatting.sgml">
+<!ENTITY func-datetime              SYSTEM "func-datetime.sgml">
+<!ENTITY func-enum                  SYSTEM "func-enum.sgml">
+<!ENTITY func-geometry              SYSTEM "func-geometry.sgml">
+<!ENTITY func-net                   SYSTEM "func-net.sgml">
+<!ENTITY func-textsearch            SYSTEM "func-textsearch.sgml">
+<!ENTITY func-uuid                  SYSTEM "func-uuid.sgml">
+<!ENTITY func-xml                   SYSTEM "func-xml.sgml">
+<!ENTITY func-json                  SYSTEM "func-json.sgml">
+<!ENTITY func-sequence              SYSTEM "func-sequence.sgml">
+<!ENTITY func-conditional           SYSTEM "func-conditional.sgml">
+<!ENTITY func-array                 SYSTEM "func-array.sgml">
+<!ENTITY func-range                 SYSTEM "func-range.sgml">
+<!ENTITY func-aggregate             SYSTEM "func-aggregate.sgml">
+<!ENTITY func-window                SYSTEM "func-window.sgml">
+<!ENTITY func-merge-support         SYSTEM "func-merge-support.sgml">
+<!ENTITY func-subquery              SYSTEM "func-subquery.sgml">
+<!ENTITY func-comparisons           SYSTEM "func-comparisons.sgml">
+<!ENTITY func-srf                   SYSTEM "func-srf.sgml">
+<!ENTITY func-info                  SYSTEM "func-info.sgml">
+<!ENTITY func-admin                 SYSTEM "func-admin.sgml">
+<!ENTITY func-trigger               SYSTEM "func-trigger.sgml">
+<!ENTITY func-event-triggers        SYSTEM "func-event-triggers.sgml">
+<!ENTITY func-statistics            SYSTEM "func-statistics.sgml">
diff --git a/doc/src/sgml/func/func-admin.sgml b/doc/src/sgml/func/func-admin.sgml
new file mode 100644
index 0000000000000..446fdfe56f4f9
--- /dev/null
+++ b/doc/src/sgml/func/func-admin.sgml
@@ -0,0 +1,2962 @@
+  <sect1 id="functions-admin">
+   <title>System Administration Functions</title>
+
+   <para>
+    The functions described in this section are used to control and
+    monitor a <productname>PostgreSQL</productname> installation.
+   </para>
+
+  <sect2 id="functions-admin-set">
+   <title>Configuration Settings Functions</title>
+
+   <indexterm>
+    <primary>SET</primary>
+   </indexterm>
+
+   <indexterm>
+    <primary>SHOW</primary>
+   </indexterm>
+
+   <indexterm>
+    <primary>configuration</primary>
+    <secondary sortas="server">of the server</secondary>
+    <tertiary>functions</tertiary>
+   </indexterm>
+
+   <para>
+    <xref linkend="functions-admin-set-table"/> shows the functions
+    available to query and alter run-time configuration parameters.
+   </para>
+
+   <table id="functions-admin-set-table">
+    <title>Configuration Settings Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>current_setting</primary>
+        </indexterm>
+        <function>current_setting</function> ( <parameter>setting_name</parameter> <type>text</type> <optional>, <parameter>missing_ok</parameter> <type>boolean</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the current value of the
+        setting <parameter>setting_name</parameter>.  If there is no such
+        setting, <function>current_setting</function> throws an error
+        unless <parameter>missing_ok</parameter> is supplied and
+        is <literal>true</literal> (in which case NULL is returned).
+        This function corresponds to
+        the <acronym>SQL</acronym> command <xref linkend="sql-show"/>.
+       </para>
+       <para>
+        <literal>current_setting('datestyle')</literal>
+        <returnvalue>ISO, MDY</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>set_config</primary>
+        </indexterm>
+        <function>set_config</function> (
+          <parameter>setting_name</parameter> <type>text</type>,
+          <parameter>new_value</parameter> <type>text</type>,
+          <parameter>is_local</parameter> <type>boolean</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Sets the parameter <parameter>setting_name</parameter>
+        to <parameter>new_value</parameter>, and returns that value.
+        If <parameter>is_local</parameter> is <literal>true</literal>, the new
+        value will only apply during the current transaction. If you want the
+        new value to apply for the rest of the current session,
+        use <literal>false</literal> instead. This function corresponds to
+        the SQL command <xref linkend="sql-set"/>.
+       </para>
+       <para>
+        <function>set_config</function> accepts the NULL value for
+        <parameter>new_value</parameter>, but as settings cannot be null, it
+        is interpreted as a request to reset the setting to its default value.
+       </para>
+       <para>
+        <literal>set_config('log_statement_stats', 'off', false)</literal>
+        <returnvalue>off</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  </sect2>
+
+  <sect2 id="functions-admin-signal">
+   <title>Server Signaling Functions</title>
+
+   <indexterm>
+    <primary>signal</primary>
+    <secondary sortas="backend">backend processes</secondary>
+   </indexterm>
+
+   <para>
+    The functions shown in <xref
+    linkend="functions-admin-signal-table"/> send control signals to
+    other server processes.  Use of these functions is restricted to
+    superusers by default but access may be granted to others using
+    <command>GRANT</command>, with noted exceptions.
+   </para>
+
+   <para>
+    Each of these functions returns <literal>true</literal> if
+    the signal was successfully sent and <literal>false</literal>
+    if sending the signal failed.
+   </para>
+
+   <table id="functions-admin-signal-table">
+    <title>Server Signaling Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_cancel_backend</primary>
+        </indexterm>
+        <function>pg_cancel_backend</function> ( <parameter>pid</parameter> <type>integer</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Cancels the current query of the session whose backend process has the
+        specified process ID.  This is also allowed if the
+        calling role is a member of the role whose backend is being canceled or
+        the calling role has privileges of <literal>pg_signal_backend</literal>,
+        however only superusers can cancel superuser backends.
+        As an exception, roles with privileges of
+        <literal>pg_signal_autovacuum_worker</literal> are permitted to
+        cancel autovacuum worker processes, which are otherwise considered
+        superuser backends.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_log_backend_memory_contexts</primary>
+        </indexterm>
+        <function>pg_log_backend_memory_contexts</function> ( <parameter>pid</parameter> <type>integer</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Requests to log the memory contexts of the backend with the
+        specified process ID.  This function can send the request to
+        backends and auxiliary processes except logger.  These memory contexts
+        will be logged at
+        <literal>LOG</literal> message level. They will appear in
+        the server log based on the log configuration set
+        (see <xref linkend="runtime-config-logging"/> for more information),
+        but will not be sent to the client regardless of
+        <xref linkend="guc-client-min-messages"/>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_reload_conf</primary>
+        </indexterm>
+        <function>pg_reload_conf</function> ()
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Causes all processes of the <productname>PostgreSQL</productname>
+        server to reload their configuration files.  (This is initiated by
+        sending a <systemitem>SIGHUP</systemitem> signal to the postmaster
+        process, which in turn sends <systemitem>SIGHUP</systemitem> to each
+        of its children.) You can use the
+        <link linkend="view-pg-file-settings"><structname>pg_file_settings</structname></link>,
+        <link linkend="view-pg-hba-file-rules"><structname>pg_hba_file_rules</structname></link> and
+        <link linkend="view-pg-ident-file-mappings"><structname>pg_ident_file_mappings</structname></link> views
+        to check the configuration files for possible errors, before reloading.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_rotate_logfile</primary>
+        </indexterm>
+        <function>pg_rotate_logfile</function> ()
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Signals the log-file manager to switch to a new output file
+        immediately.  This works only when the built-in log collector is
+        running, since otherwise there is no log-file manager subprocess.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_terminate_backend</primary>
+        </indexterm>
+        <function>pg_terminate_backend</function> ( <parameter>pid</parameter> <type>integer</type>, <parameter>timeout</parameter> <type>bigint</type> <literal>DEFAULT</literal> <literal>0</literal> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Terminates the session whose backend process has the
+        specified process ID.  This is also allowed if the calling role
+        is a member of the role whose backend is being terminated or the
+        calling role has privileges of <literal>pg_signal_backend</literal>,
+        however only superusers can terminate superuser backends.
+        As an exception, roles with privileges of
+        <literal>pg_signal_autovacuum_worker</literal> are permitted to
+        terminate autovacuum worker processes, which are otherwise considered
+        superuser backends.
+       </para>
+       <para>
+        If <parameter>timeout</parameter> is not specified or zero, this
+        function returns <literal>true</literal> whether the process actually
+        terminates or not, indicating only that the sending of the signal was
+        successful.  If the <parameter>timeout</parameter> is specified (in
+        milliseconds) and greater than zero, the function waits until the
+        process is actually terminated or until the given time has passed. If
+        the process is terminated, the function
+        returns <literal>true</literal>.  On timeout, a warning is emitted and
+        <literal>false</literal> is returned.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    <function>pg_cancel_backend</function> and <function>pg_terminate_backend</function>
+    send signals (<systemitem>SIGINT</systemitem> or <systemitem>SIGTERM</systemitem>
+    respectively) to backend processes identified by process ID.
+    The process ID of an active backend can be found from
+    the <structfield>pid</structfield> column of the
+    <structname>pg_stat_activity</structname> view, or by listing the
+    <command>postgres</command> processes on the server (using
+    <application>ps</application> on Unix or the <application>Task
+    Manager</application> on <productname>Windows</productname>).
+    The role of an active backend can be found from the
+    <structfield>usename</structfield> column of the
+    <structname>pg_stat_activity</structname> view.
+   </para>
+
+   <para>
+    <function>pg_log_backend_memory_contexts</function> can be used
+    to log the memory contexts of a backend process. For example:
+<programlisting>
+postgres=# SELECT pg_log_backend_memory_contexts(pg_backend_pid());
+ pg_log_backend_memory_contexts
+--------------------------------
+ t
+(1 row)
+</programlisting>
+One message for each memory context will be logged. For example:
+<screen>
+LOG:  logging memory contexts of PID 10377
+STATEMENT:  SELECT pg_log_backend_memory_contexts(pg_backend_pid());
+LOG:  level: 1; TopMemoryContext: 80800 total in 6 blocks; 14432 free (5 chunks); 66368 used
+LOG:  level: 2; pgstat TabStatusArray lookup hash table: 8192 total in 1 blocks; 1408 free (0 chunks); 6784 used
+LOG:  level: 2; TopTransactionContext: 8192 total in 1 blocks; 7720 free (1 chunks); 472 used
+LOG:  level: 2; RowDescriptionContext: 8192 total in 1 blocks; 6880 free (0 chunks); 1312 used
+LOG:  level: 2; MessageContext: 16384 total in 2 blocks; 5152 free (0 chunks); 11232 used
+LOG:  level: 2; Operator class cache: 8192 total in 1 blocks; 512 free (0 chunks); 7680 used
+LOG:  level: 2; smgr relation table: 16384 total in 2 blocks; 4544 free (3 chunks); 11840 used
+LOG:  level: 2; TransactionAbortContext: 32768 total in 1 blocks; 32504 free (0 chunks); 264 used
+...
+LOG:  level: 2; ErrorContext: 8192 total in 1 blocks; 7928 free (3 chunks); 264 used
+LOG:  Grand total: 1651920 bytes in 201 blocks; 622360 free (88 chunks); 1029560 used
+</screen>
+    If there are more than 100 child contexts under the same parent, the first
+    100 child contexts are logged, along with a summary of the remaining contexts.
+    Note that frequent calls to this function could incur significant overhead,
+    because it may generate a large number of log messages.
+   </para>
+
+  </sect2>
+
+  <sect2 id="functions-admin-backup">
+   <title>Backup Control Functions</title>
+
+   <indexterm>
+    <primary>backup</primary>
+   </indexterm>
+
+   <para>
+    The functions shown in <xref
+    linkend="functions-admin-backup-table"/> assist in making on-line backups.
+    These functions cannot be executed during recovery (except
+    <function>pg_backup_start</function>,
+    <function>pg_backup_stop</function>,
+    and <function>pg_wal_lsn_diff</function>).
+   </para>
+
+   <para>
+    For details about proper usage of these functions, see
+    <xref linkend="continuous-archiving"/>.
+   </para>
+
+   <table id="functions-admin-backup-table">
+    <title>Backup Control Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_create_restore_point</primary>
+        </indexterm>
+        <function>pg_create_restore_point</function> ( <parameter>name</parameter> <type>text</type> )
+        <returnvalue>pg_lsn</returnvalue>
+       </para>
+       <para>
+        Creates a named marker record in the write-ahead log that can later be
+        used as a recovery target, and returns the corresponding write-ahead
+        log location.  The given name can then be used with
+        <xref linkend="guc-recovery-target-name"/> to specify the point up to
+        which recovery will proceed.  Avoid creating multiple restore points
+        with the same name, since recovery will stop at the first one whose
+        name matches the recovery target.
+       </para>
+       <para>
+        This function is restricted to superusers by default, but other users
+        can be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_current_wal_flush_lsn</primary>
+        </indexterm>
+        <function>pg_current_wal_flush_lsn</function> ()
+        <returnvalue>pg_lsn</returnvalue>
+       </para>
+       <para>
+        Returns the current write-ahead log flush location (see notes below).
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_current_wal_insert_lsn</primary>
+        </indexterm>
+        <function>pg_current_wal_insert_lsn</function> ()
+        <returnvalue>pg_lsn</returnvalue>
+       </para>
+       <para>
+        Returns the current write-ahead log insert location (see notes below).
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_current_wal_lsn</primary>
+        </indexterm>
+        <function>pg_current_wal_lsn</function> ()
+        <returnvalue>pg_lsn</returnvalue>
+       </para>
+       <para>
+        Returns the current write-ahead log write location (see notes below).
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_backup_start</primary>
+        </indexterm>
+        <function>pg_backup_start</function> (
+          <parameter>label</parameter> <type>text</type>
+          <optional>, <parameter>fast</parameter> <type>boolean</type>
+          </optional> )
+        <returnvalue>pg_lsn</returnvalue>
+       </para>
+       <para>
+        Prepares the server to begin an on-line backup.  The only required
+        parameter is an arbitrary user-defined label for the backup.
+        (Typically this would be the name under which the backup dump file
+        will be stored.)
+        If the optional second parameter is given as <literal>true</literal>,
+        it specifies executing <function>pg_backup_start</function> as quickly
+        as possible.  This forces a fast checkpoint which will cause a
+        spike in I/O operations, slowing any concurrently executing queries.
+       </para>
+       <para>
+        This function is restricted to superusers by default, but other users
+        can be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_backup_stop</primary>
+        </indexterm>
+        <function>pg_backup_stop</function> (
+          <optional><parameter>wait_for_archive</parameter> <type>boolean</type>
+          </optional> )
+        <returnvalue>record</returnvalue>
+        ( <parameter>lsn</parameter> <type>pg_lsn</type>,
+        <parameter>labelfile</parameter> <type>text</type>,
+        <parameter>spcmapfile</parameter> <type>text</type> )
+       </para>
+       <para>
+        Finishes performing an on-line backup.  The desired contents of the
+        backup label file and the tablespace map file are returned as part of
+        the result of the function and must be written to files in the
+        backup area.  These files must not be written to the live data directory
+        (doing so will cause PostgreSQL to fail to restart in the event of a
+        crash).
+       </para>
+       <para>
+        There is an optional parameter of type <type>boolean</type>.
+        If false, the function will return immediately after the backup is
+        completed, without waiting for WAL to be archived.  This behavior is
+        only useful with backup software that independently monitors WAL
+        archiving.  Otherwise, WAL required to make the backup consistent might
+        be missing and make the backup useless.  By default or when this
+        parameter is true, <function>pg_backup_stop</function> will wait for
+        WAL to be archived when archiving is enabled.  (On a standby, this
+        means that it will wait only when <varname>archive_mode</varname> =
+        <literal>always</literal>.  If write activity on the primary is low,
+        it may be useful to run <function>pg_switch_wal</function> on the
+        primary in order to trigger an immediate segment switch.)
+       </para>
+       <para>
+        When executed on a primary, this function also creates a backup
+        history file in the write-ahead log archive area.  The history file
+        includes the label given to <function>pg_backup_start</function>, the
+        starting and ending write-ahead log locations for the backup, and the
+        starting and ending times of the backup.  After recording the ending
+        location, the current write-ahead log insertion point is automatically
+        advanced to the next write-ahead log file, so that the ending
+        write-ahead log file can be archived immediately to complete the
+        backup.
+       </para>
+       <para>
+        The result of the function is a single record.
+        The <parameter>lsn</parameter> column holds the backup's ending
+        write-ahead log location (which again can be ignored).  The second
+        column returns the contents of the backup label file, and the third
+        column returns the contents of the tablespace map file.  These must be
+        stored as part of the backup and are required as part of the restore
+        process.
+       </para>
+       <para>
+        This function is restricted to superusers by default, but other users
+        can be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_switch_wal</primary>
+        </indexterm>
+        <function>pg_switch_wal</function> ()
+        <returnvalue>pg_lsn</returnvalue>
+       </para>
+       <para>
+        Forces the server to switch to a new write-ahead log file, which
+        allows the current file to be archived (assuming you are using
+        continuous archiving).  The result is the ending write-ahead log
+        location plus 1 within the just-completed write-ahead log file.  If
+        there has been no write-ahead log activity since the last write-ahead
+        log switch, <function>pg_switch_wal</function> does nothing and
+        returns the start location of the write-ahead log file currently in
+        use.
+       </para>
+       <para>
+        This function is restricted to superusers by default, but other users
+        can be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_walfile_name</primary>
+        </indexterm>
+        <function>pg_walfile_name</function> ( <parameter>lsn</parameter> <type>pg_lsn</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts a write-ahead log location to the name of the WAL file
+        holding that location.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_walfile_name_offset</primary>
+        </indexterm>
+        <function>pg_walfile_name_offset</function> ( <parameter>lsn</parameter> <type>pg_lsn</type> )
+        <returnvalue>record</returnvalue>
+        ( <parameter>file_name</parameter> <type>text</type>,
+        <parameter>file_offset</parameter> <type>integer</type> )
+       </para>
+       <para>
+        Converts a write-ahead log location to a WAL file name and byte offset
+        within that file.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_split_walfile_name</primary>
+        </indexterm>
+        <function>pg_split_walfile_name</function> ( <parameter>file_name</parameter> <type>text</type> )
+        <returnvalue>record</returnvalue>
+        ( <parameter>segment_number</parameter> <type>numeric</type>,
+        <parameter>timeline_id</parameter> <type>bigint</type> )
+       </para>
+       <para>
+        Extracts the sequence number and timeline ID from a WAL file
+        name.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_wal_lsn_diff</primary>
+        </indexterm>
+        <function>pg_wal_lsn_diff</function> ( <parameter>lsn1</parameter> <type>pg_lsn</type>, <parameter>lsn2</parameter> <type>pg_lsn</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para>
+        Calculates the difference in bytes (<parameter>lsn1</parameter> - <parameter>lsn2</parameter>) between two write-ahead log
+        locations.  This can be used
+        with <structname>pg_stat_replication</structname> or some of the
+        functions shown in <xref linkend="functions-admin-backup-table"/> to
+        get the replication lag.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    <function>pg_current_wal_lsn</function> displays the current write-ahead
+    log write location in the same format used by the above functions.
+    Similarly, <function>pg_current_wal_insert_lsn</function> displays the
+    current write-ahead log insertion location
+    and <function>pg_current_wal_flush_lsn</function> displays the current
+    write-ahead log flush location. The insertion location is
+    the <quote>logical</quote> end of the write-ahead log at any instant,
+    while the write location is the end of what has actually been written out
+    from the server's internal buffers, and the flush location is the last
+    location known to be written to durable storage. The write location is the
+    end of what can be examined from outside the server, and is usually what
+    you want if you are interested in archiving partially-complete write-ahead
+    log files.  The insertion and flush locations are made available primarily
+    for server debugging purposes.  These are all read-only operations and do
+    not require superuser permissions.
+   </para>
+
+   <para>
+    You can use <function>pg_walfile_name_offset</function> to extract the
+    corresponding write-ahead log file name and byte offset from
+    a <type>pg_lsn</type> value.  For example:
+<programlisting>
+postgres=# SELECT * FROM pg_walfile_name_offset((pg_backup_stop()).lsn);
+        file_name         | file_offset
+--------------------------+-------------
+ 00000001000000000000000D |     4039624
+(1 row)
+</programlisting>
+    Similarly, <function>pg_walfile_name</function> extracts just the write-ahead log file name.
+   </para>
+
+   <para>
+    <function>pg_split_walfile_name</function> is useful to compute a
+    <acronym>LSN</acronym> from a file offset and WAL file name, for example:
+<programlisting>
+postgres=# \set file_name '000000010000000100C000AB'
+postgres=# \set offset 256
+postgres=# SELECT '0/0'::pg_lsn + pd.segment_number * ps.setting::int + :offset AS lsn
+  FROM pg_split_walfile_name(:'file_name') pd,
+       pg_show_all_settings() ps
+  WHERE ps.name = 'wal_segment_size';
+      lsn
+---------------
+ C001/AB000100
+(1 row)
+</programlisting>
+   </para>
+
+  </sect2>
+
+  <sect2 id="functions-recovery-control">
+   <title>Recovery Control Functions</title>
+
+   <para>
+    The functions shown in <xref
+    linkend="functions-recovery-info-table"/> provide information
+    about the current status of a standby server.
+    These functions may be executed both during recovery and in normal running.
+   </para>
+
+   <table id="functions-recovery-info-table">
+    <title>Recovery Information Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_is_in_recovery</primary>
+        </indexterm>
+        <function>pg_is_in_recovery</function> ()
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Returns true if recovery is still in progress.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_last_wal_receive_lsn</primary>
+        </indexterm>
+        <function>pg_last_wal_receive_lsn</function> ()
+        <returnvalue>pg_lsn</returnvalue>
+       </para>
+       <para>
+        Returns the last write-ahead log location that has been received and
+        synced to disk by streaming replication. While streaming replication
+        is in progress this will increase monotonically. If recovery has
+        completed then this will remain static at the location of the last WAL
+        record received and synced to disk during recovery. If streaming
+        replication is disabled, or if it has not yet started, the function
+        returns <literal>NULL</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_last_wal_replay_lsn</primary>
+        </indexterm>
+        <function>pg_last_wal_replay_lsn</function> ()
+        <returnvalue>pg_lsn</returnvalue>
+       </para>
+       <para>
+        Returns the last write-ahead log location that has been replayed
+        during recovery.  If recovery is still in progress this will increase
+        monotonically.  If recovery has completed then this will remain
+        static at the location of the last WAL record applied during recovery.
+        When the server has been started normally without recovery, the
+        function returns <literal>NULL</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_last_xact_replay_timestamp</primary>
+        </indexterm>
+        <function>pg_last_xact_replay_timestamp</function> ()
+        <returnvalue>timestamp with time zone</returnvalue>
+       </para>
+       <para>
+        Returns the time stamp of the last transaction replayed during
+        recovery.  This is the time at which the commit or abort WAL record
+        for that transaction was generated on the primary.  If no transactions
+        have been replayed during recovery, the function
+        returns <literal>NULL</literal>.  Otherwise, if recovery is still in
+        progress this will increase monotonically.  If recovery has completed
+        then this will remain static at the time of the last transaction
+        applied during recovery.  When the server has been started normally
+        without recovery, the function returns <literal>NULL</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_wal_resource_managers</primary>
+        </indexterm>
+        <function>pg_get_wal_resource_managers</function> ()
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>rm_id</parameter> <type>integer</type>,
+        <parameter>rm_name</parameter> <type>text</type>,
+        <parameter>rm_builtin</parameter> <type>boolean</type> )
+       </para>
+       <para>
+        Returns the currently-loaded WAL resource managers in the system. The
+        column <parameter>rm_builtin</parameter> indicates whether it's a
+        built-in resource manager, or a custom resource manager loaded by an
+        extension.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    The functions shown in <xref
+    linkend="functions-recovery-control-table"/> control the progress of recovery.
+    These functions may be executed only during recovery.
+   </para>
+
+   <table id="functions-recovery-control-table">
+    <title>Recovery Control Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_is_wal_replay_paused</primary>
+        </indexterm>
+        <function>pg_is_wal_replay_paused</function> ()
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Returns true if recovery pause is requested.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_wal_replay_pause_state</primary>
+        </indexterm>
+        <function>pg_get_wal_replay_pause_state</function> ()
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns recovery pause state.  The return values are <literal>
+        not paused</literal> if pause is not requested, <literal>
+        pause requested</literal> if pause is requested but recovery is
+        not yet paused, and <literal>paused</literal> if the recovery is
+        actually paused.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_promote</primary>
+        </indexterm>
+        <function>pg_promote</function> ( <parameter>wait</parameter> <type>boolean</type> <literal>DEFAULT</literal> <literal>true</literal>, <parameter>wait_seconds</parameter> <type>integer</type> <literal>DEFAULT</literal> <literal>60</literal> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Promotes a standby server to primary status.
+        With <parameter>wait</parameter> set to <literal>true</literal> (the
+        default), the function waits until promotion is completed
+        or <parameter>wait_seconds</parameter> seconds have passed, and
+        returns <literal>true</literal> if promotion is successful
+        and <literal>false</literal> otherwise.
+        If <parameter>wait</parameter> is set to <literal>false</literal>, the
+        function returns <literal>true</literal> immediately after sending a
+        <literal>SIGUSR1</literal> signal to the postmaster to trigger
+        promotion.
+       </para>
+       <para>
+        This function is restricted to superusers by default, but other users
+        can be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_wal_replay_pause</primary>
+        </indexterm>
+        <function>pg_wal_replay_pause</function> ()
+        <returnvalue>void</returnvalue>
+       </para>
+       <para>
+        Request to pause recovery.  A request doesn't mean that recovery stops
+        right away.  If you want a guarantee that recovery is actually paused,
+        you need to check for the recovery pause state returned by
+        <function>pg_get_wal_replay_pause_state()</function>.  Note that
+        <function>pg_is_wal_replay_paused()</function> returns whether a request
+        is made.  While recovery is paused, no further database changes are applied.
+        If hot standby is active, all new queries will see the same consistent
+        snapshot of the database, and no further query conflicts will be generated
+        until recovery is resumed.
+       </para>
+       <para>
+        This function is restricted to superusers by default, but other users
+        can be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_wal_replay_resume</primary>
+        </indexterm>
+        <function>pg_wal_replay_resume</function> ()
+        <returnvalue>void</returnvalue>
+       </para>
+       <para>
+        Restarts recovery if it was paused.
+       </para>
+       <para>
+        This function is restricted to superusers by default, but other users
+        can be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    <function>pg_wal_replay_pause</function> and
+    <function>pg_wal_replay_resume</function> cannot be executed while
+    a promotion is ongoing. If a promotion is triggered while recovery
+    is paused, the paused state ends and promotion continues.
+   </para>
+
+   <para>
+    If streaming replication is disabled, the paused state may continue
+    indefinitely without a problem. If streaming replication is in
+    progress then WAL records will continue to be received, which will
+    eventually fill available disk space, depending upon the duration of
+    the pause, the rate of WAL generation and available disk space.
+   </para>
+
+  </sect2>
+
+  <sect2 id="functions-snapshot-synchronization">
+   <title>Snapshot Synchronization Functions</title>
+
+   <para>
+    <productname>PostgreSQL</productname> allows database sessions to synchronize their
+    snapshots. A <firstterm>snapshot</firstterm> determines which data is visible to the
+    transaction that is using the snapshot. Synchronized snapshots are
+    necessary when two or more sessions need to see identical content in the
+    database. If two sessions just start their transactions independently,
+    there is always a possibility that some third transaction commits
+    between the executions of the two <command>START TRANSACTION</command> commands,
+    so that one session sees the effects of that transaction and the other
+    does not.
+   </para>
+
+   <para>
+    To solve this problem, <productname>PostgreSQL</productname> allows a transaction to
+    <firstterm>export</firstterm> the snapshot it is using.  As long as the exporting
+    transaction remains open, other transactions can <firstterm>import</firstterm> its
+    snapshot, and thereby be guaranteed that they see exactly the same view
+    of the database that the first transaction sees.  But note that any
+    database changes made by any one of these transactions remain invisible
+    to the other transactions, as is usual for changes made by uncommitted
+    transactions.  So the transactions are synchronized with respect to
+    pre-existing data, but act normally for changes they make themselves.
+   </para>
+
+   <para>
+    Snapshots are exported with the <function>pg_export_snapshot</function> function,
+    shown in <xref linkend="functions-snapshot-synchronization-table"/>, and
+    imported with the <xref linkend="sql-set-transaction"/> command.
+   </para>
+
+   <table id="functions-snapshot-synchronization-table">
+    <title>Snapshot Synchronization Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_export_snapshot</primary>
+        </indexterm>
+        <function>pg_export_snapshot</function> ()
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Saves the transaction's current snapshot and returns
+        a <type>text</type> string identifying the snapshot.  This string must
+        be passed (outside the database) to clients that want to import the
+        snapshot.  The snapshot is available for import only until the end of
+        the transaction that exported it.
+       </para>
+       <para>
+        A transaction can export more than one snapshot, if needed.  Note that
+        doing so is only useful in <literal>READ COMMITTED</literal>
+        transactions, since in <literal>REPEATABLE READ</literal> and higher
+        isolation levels, transactions use the same snapshot throughout their
+        lifetime.  Once a transaction has exported any snapshots, it cannot be
+        prepared with <xref linkend="sql-prepare-transaction"/>.
+       </para></entry>
+      </row>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_log_standby_snapshot</primary>
+        </indexterm>
+        <function>pg_log_standby_snapshot</function> ()
+        <returnvalue>pg_lsn</returnvalue>
+       </para>
+       <para>
+        Take a snapshot of running transactions and write it to WAL, without
+        having to wait for bgwriter or checkpointer to log one. This is useful
+        for logical decoding on standby, as logical slot creation has to wait
+        until such a record is replayed on the standby.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  </sect2>
+
+  <sect2 id="functions-replication">
+   <title>Replication Management Functions</title>
+
+   <para>
+    The functions shown
+    in <xref linkend="functions-replication-table"/> are for
+    controlling and interacting with replication features.
+    See <xref linkend="streaming-replication"/>,
+    <xref linkend="streaming-replication-slots"/>, and
+    <xref linkend="replication-origins"/>
+    for information about the underlying features.
+    Use of functions for replication origin is only allowed to the
+    superuser by default, but may be allowed to other users by using the
+    <literal>GRANT</literal> command.
+    Use of functions for replication slots is restricted to superusers
+    and users having <literal>REPLICATION</literal> privilege.
+   </para>
+
+   <para>
+    Many of these functions have equivalent commands in the replication
+    protocol; see <xref linkend="protocol-replication"/>.
+   </para>
+
+   <para>
+    The functions described in
+    <xref linkend="functions-admin-backup"/>,
+    <xref linkend="functions-recovery-control"/>, and
+    <xref linkend="functions-snapshot-synchronization"/>
+    are also relevant for replication.
+   </para>
+
+   <table id="functions-replication-table">
+    <title>Replication Management Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_create_physical_replication_slot</primary>
+        </indexterm>
+        <function>pg_create_physical_replication_slot</function> ( <parameter>slot_name</parameter> <type>name</type> <optional>, <parameter>immediately_reserve</parameter> <type>boolean</type>, <parameter>temporary</parameter> <type>boolean</type> </optional> )
+        <returnvalue>record</returnvalue>
+        ( <parameter>slot_name</parameter> <type>name</type>,
+        <parameter>lsn</parameter> <type>pg_lsn</type> )
+       </para>
+       <para>
+        Creates a new physical replication slot named
+        <parameter>slot_name</parameter>. The name cannot be
+        <literal>pg_conflict_detection</literal> as it is reserved for the
+        conflict detection slot. The optional second parameter,
+        when <literal>true</literal>, specifies that the <acronym>LSN</acronym> for this
+        replication slot be reserved immediately; otherwise
+        the <acronym>LSN</acronym> is reserved on first connection from a streaming
+        replication client. Streaming changes from a physical slot is only
+        possible with the streaming-replication protocol &mdash;
+        see <xref linkend="protocol-replication"/>. The optional third
+        parameter, <parameter>temporary</parameter>, when set to true, specifies that
+        the slot should not be permanently stored to disk and is only meant
+        for use by the current session. Temporary slots are also
+        released upon any error. This function corresponds
+        to the replication protocol command <literal>CREATE_REPLICATION_SLOT
+        ... PHYSICAL</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_drop_replication_slot</primary>
+        </indexterm>
+        <function>pg_drop_replication_slot</function> ( <parameter>slot_name</parameter> <type>name</type> )
+        <returnvalue>void</returnvalue>
+       </para>
+       <para>
+        Drops the physical or logical replication slot
+        named <parameter>slot_name</parameter>. Same as replication protocol
+        command <literal>DROP_REPLICATION_SLOT</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="pg-create-logical-replication-slot" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_create_logical_replication_slot</primary>
+        </indexterm>
+        <function>pg_create_logical_replication_slot</function> ( <parameter>slot_name</parameter> <type>name</type>, <parameter>plugin</parameter> <type>name</type> <optional>, <parameter>temporary</parameter> <type>boolean</type>, <parameter>twophase</parameter> <type>boolean</type>, <parameter>failover</parameter> <type>boolean</type> </optional> )
+        <returnvalue>record</returnvalue>
+        ( <parameter>slot_name</parameter> <type>name</type>,
+        <parameter>lsn</parameter> <type>pg_lsn</type> )
+       </para>
+       <para>
+        Creates a new logical (decoding) replication slot named
+        <parameter>slot_name</parameter> using the output plugin
+        <parameter>plugin</parameter>. The name cannot be
+        <literal>pg_conflict_detection</literal> as it is reserved for
+        the conflict detection slot. The optional third
+        parameter, <parameter>temporary</parameter>, when set to true, specifies that
+        the slot should not be permanently stored to disk and is only meant
+        for use by the current session. Temporary slots are also
+        released upon any error. The optional fourth parameter,
+        <parameter>twophase</parameter>, when set to true, specifies
+        that the decoding of prepared transactions is enabled for this
+        slot. The optional fifth parameter,
+        <parameter>failover</parameter>, when set to true,
+        specifies that this slot is enabled to be synced to the
+        standbys so that logical replication can be resumed after
+        failover. A call to this function has the same effect as
+        the replication protocol command
+        <literal>CREATE_REPLICATION_SLOT ... LOGICAL</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_copy_physical_replication_slot</primary>
+        </indexterm>
+        <function>pg_copy_physical_replication_slot</function> ( <parameter>src_slot_name</parameter> <type>name</type>, <parameter>dst_slot_name</parameter> <type>name</type> <optional>, <parameter>temporary</parameter> <type>boolean</type> </optional> )
+        <returnvalue>record</returnvalue>
+        ( <parameter>slot_name</parameter> <type>name</type>,
+        <parameter>lsn</parameter> <type>pg_lsn</type> )
+       </para>
+       <para>
+        Copies an existing physical replication slot named <parameter>src_slot_name</parameter>
+        to a physical replication slot named <parameter>dst_slot_name</parameter>.
+        The new slot name cannot be <literal>pg_conflict_detection</literal>,
+        as it is reserved for the conflict detection.
+        The copied physical slot starts to reserve WAL from the same <acronym>LSN</acronym> as the
+        source slot.
+        <parameter>temporary</parameter> is optional. If <parameter>temporary</parameter>
+        is omitted, the same value as the source slot is used. Copy of an
+        invalidated slot is not allowed.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_copy_logical_replication_slot</primary>
+        </indexterm>
+        <function>pg_copy_logical_replication_slot</function> ( <parameter>src_slot_name</parameter> <type>name</type>, <parameter>dst_slot_name</parameter> <type>name</type> <optional>, <parameter>temporary</parameter> <type>boolean</type> <optional>, <parameter>plugin</parameter> <type>name</type> </optional></optional> )
+        <returnvalue>record</returnvalue>
+        ( <parameter>slot_name</parameter> <type>name</type>,
+        <parameter>lsn</parameter> <type>pg_lsn</type> )
+       </para>
+       <para>
+        Copies an existing logical replication slot
+        named <parameter>src_slot_name</parameter> to a logical replication
+        slot named <parameter>dst_slot_name</parameter>, optionally changing
+        the output plugin and persistence.  The new slot name cannot be
+        <literal>pg_conflict_detection</literal> as it is reserved for
+        the conflict detection.  The copied logical slot starts from the same
+        <acronym>LSN</acronym> as the source logical slot.  Both
+        <parameter>temporary</parameter> and <parameter>plugin</parameter> are
+        optional; if they are omitted, the values of the source slot are used.
+        The <literal>failover</literal> option of the source logical slot
+        is not copied and is set to <literal>false</literal> by default. This
+        is to avoid the risk of being unable to continue logical replication
+        after failover to standby where the slot is being synchronized. Copy of
+        an invalidated slot is not allowed.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="pg-logical-slot-get-changes" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_logical_slot_get_changes</primary>
+        </indexterm>
+        <function>pg_logical_slot_get_changes</function> ( <parameter>slot_name</parameter> <type>name</type>, <parameter>upto_lsn</parameter> <type>pg_lsn</type>, <parameter>upto_nchanges</parameter> <type>integer</type>, <literal>VARIADIC</literal> <parameter>options</parameter> <type>text[]</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>lsn</parameter> <type>pg_lsn</type>,
+        <parameter>xid</parameter> <type>xid</type>,
+        <parameter>data</parameter> <type>text</type> )
+       </para>
+       <para>
+        Returns changes in the slot <parameter>slot_name</parameter>, starting
+        from the point from which changes have been consumed last.  If
+        <parameter>upto_lsn</parameter>
+        and <parameter>upto_nchanges</parameter> are NULL,
+        logical decoding will continue until end of WAL.  If
+        <parameter>upto_lsn</parameter> is non-NULL, decoding will include only
+        those transactions which commit prior to the specified LSN.  If
+        <parameter>upto_nchanges</parameter> is non-NULL, decoding will
+        stop when the number of rows produced by decoding exceeds
+        the specified value.  Note, however, that the actual number of
+        rows returned may be larger, since this limit is only checked after
+        adding the rows produced when decoding each new transaction commit.
+        If the specified slot is a logical failover slot then the function will
+        not return until all physical slots specified in
+        <link linkend="guc-synchronized-standby-slots"><varname>synchronized_standby_slots</varname></link>
+        have confirmed WAL receipt.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="pg-logical-slot-peek-changes" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_logical_slot_peek_changes</primary>
+        </indexterm>
+        <function>pg_logical_slot_peek_changes</function> ( <parameter>slot_name</parameter> <type>name</type>, <parameter>upto_lsn</parameter> <type>pg_lsn</type>, <parameter>upto_nchanges</parameter> <type>integer</type>, <literal>VARIADIC</literal> <parameter>options</parameter> <type>text[]</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>lsn</parameter> <type>pg_lsn</type>,
+        <parameter>xid</parameter> <type>xid</type>,
+         <parameter>data</parameter> <type>text</type> )
+       </para>
+       <para>
+        Behaves just like
+        the <function>pg_logical_slot_get_changes()</function> function,
+        except that changes are not consumed; that is, they will be returned
+        again on future calls.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="pg-logical-slot-get-binary-changes" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_logical_slot_get_binary_changes</primary>
+        </indexterm>
+        <function>pg_logical_slot_get_binary_changes</function> ( <parameter>slot_name</parameter> <type>name</type>, <parameter>upto_lsn</parameter> <type>pg_lsn</type>, <parameter>upto_nchanges</parameter> <type>integer</type>, <literal>VARIADIC</literal> <parameter>options</parameter> <type>text[]</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>lsn</parameter> <type>pg_lsn</type>,
+        <parameter>xid</parameter> <type>xid</type>,
+        <parameter>data</parameter> <type>bytea</type> )
+       </para>
+       <para>
+        Behaves just like
+        the <function>pg_logical_slot_get_changes()</function> function,
+        except that changes are returned as <type>bytea</type>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_logical_slot_peek_binary_changes</primary>
+        </indexterm>
+        <function>pg_logical_slot_peek_binary_changes</function> ( <parameter>slot_name</parameter> <type>name</type>, <parameter>upto_lsn</parameter> <type>pg_lsn</type>, <parameter>upto_nchanges</parameter> <type>integer</type>, <literal>VARIADIC</literal> <parameter>options</parameter> <type>text[]</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>lsn</parameter> <type>pg_lsn</type>,
+        <parameter>xid</parameter> <type>xid</type>,
+        <parameter>data</parameter> <type>bytea</type> )
+       </para>
+       <para>
+        Behaves just like
+        the <function>pg_logical_slot_peek_changes()</function> function,
+        except that changes are returned as <type>bytea</type>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="pg-replication-slot-advance" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_replication_slot_advance</primary>
+        </indexterm>
+        <function>pg_replication_slot_advance</function> ( <parameter>slot_name</parameter> <type>name</type>, <parameter>upto_lsn</parameter> <type>pg_lsn</type> )
+        <returnvalue>record</returnvalue>
+        ( <parameter>slot_name</parameter> <type>name</type>,
+        <parameter>end_lsn</parameter> <type>pg_lsn</type> )
+       </para>
+       <para>
+        Advances the current confirmed position of a replication slot named
+        <parameter>slot_name</parameter>. The slot will not be moved backwards,
+        and it will not be moved beyond the current insert location. Returns
+        the name of the slot and the actual position that it was advanced to.
+        The updated slot position information is written out at the next
+        checkpoint if any advancing is done. So in the event of a crash, the
+        slot may return to an earlier position. If the specified slot is a
+        logical failover slot then the function will not return until all
+        physical slots specified in
+        <link linkend="guc-synchronized-standby-slots"><varname>synchronized_standby_slots</varname></link>
+        have confirmed WAL receipt.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="pg-replication-origin-create" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_replication_origin_create</primary>
+        </indexterm>
+        <function>pg_replication_origin_create</function> ( <parameter>node_name</parameter> <type>text</type> )
+        <returnvalue>oid</returnvalue>
+       </para>
+       <para>
+        Creates a replication origin with the given external
+        name, and returns the internal ID assigned to it.
+        The name must be no longer than 512 bytes.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="pg-replication-origin-drop" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_replication_origin_drop</primary>
+        </indexterm>
+        <function>pg_replication_origin_drop</function> ( <parameter>node_name</parameter> <type>text</type> )
+        <returnvalue>void</returnvalue>
+       </para>
+       <para>
+        Deletes a previously-created replication origin, including any
+        associated replay progress.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_replication_origin_oid</primary>
+        </indexterm>
+        <function>pg_replication_origin_oid</function> ( <parameter>node_name</parameter> <type>text</type> )
+        <returnvalue>oid</returnvalue>
+       </para>
+       <para>
+        Looks up a replication origin by name and returns the internal ID. If
+        no such replication origin is found, <literal>NULL</literal> is
+        returned.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="pg-replication-origin-session-setup" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_replication_origin_session_setup</primary>
+        </indexterm>
+        <function>pg_replication_origin_session_setup</function> ( <parameter>node_name</parameter> <type>text</type> )
+        <returnvalue>void</returnvalue>
+       </para>
+       <para>
+        Marks the current session as replaying from the given
+        origin, allowing replay progress to be tracked.
+        Can only be used if no origin is currently selected.
+        Use <function>pg_replication_origin_session_reset</function> to undo.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_replication_origin_session_reset</primary>
+        </indexterm>
+        <function>pg_replication_origin_session_reset</function> ()
+        <returnvalue>void</returnvalue>
+       </para>
+       <para>
+        Cancels the effects
+        of <function>pg_replication_origin_session_setup()</function>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_replication_origin_session_is_setup</primary>
+        </indexterm>
+        <function>pg_replication_origin_session_is_setup</function> ()
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Returns true if a replication origin has been selected in the
+        current session.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="pg-replication-origin-session-progress" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_replication_origin_session_progress</primary>
+        </indexterm>
+        <function>pg_replication_origin_session_progress</function> ( <parameter>flush</parameter> <type>boolean</type> )
+        <returnvalue>pg_lsn</returnvalue>
+       </para>
+       <para>
+        Returns the replay location for the replication origin selected in
+        the current session. The parameter <parameter>flush</parameter>
+        determines whether the corresponding local transaction will be
+        guaranteed to have been flushed to disk or not.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="pg-replication-origin-xact-setup" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_replication_origin_xact_setup</primary>
+        </indexterm>
+        <function>pg_replication_origin_xact_setup</function> ( <parameter>origin_lsn</parameter> <type>pg_lsn</type>, <parameter>origin_timestamp</parameter> <type>timestamp with time zone</type> )
+        <returnvalue>void</returnvalue>
+       </para>
+       <para>
+        Marks the current transaction as replaying a transaction that has
+        committed at the given <acronym>LSN</acronym> and timestamp. Can
+        only be called when a replication origin has been selected
+        using <function>pg_replication_origin_session_setup</function>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="pg-replication-origin-xact-reset" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_replication_origin_xact_reset</primary>
+        </indexterm>
+        <function>pg_replication_origin_xact_reset</function> ()
+        <returnvalue>void</returnvalue>
+       </para>
+       <para>
+        Cancels the effects of
+        <function>pg_replication_origin_xact_setup()</function>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="pg-replication-origin-advance" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_replication_origin_advance</primary>
+        </indexterm>
+        <function>pg_replication_origin_advance</function> ( <parameter>node_name</parameter> <type>text</type>, <parameter>lsn</parameter> <type>pg_lsn</type> )
+        <returnvalue>void</returnvalue>
+       </para>
+       <para>
+        Sets replication progress for the given node to the given
+        location. This is primarily useful for setting up the initial
+        location, or setting a new location after configuration changes and
+        similar. Be aware that careless use of this function can lead to
+        inconsistently replicated data.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="pg-replication-origin-progress" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_replication_origin_progress</primary>
+        </indexterm>
+        <function>pg_replication_origin_progress</function> ( <parameter>node_name</parameter> <type>text</type>, <parameter>flush</parameter> <type>boolean</type> )
+        <returnvalue>pg_lsn</returnvalue>
+       </para>
+       <para>
+        Returns the replay location for the given replication origin. The
+        parameter <parameter>flush</parameter> determines whether the
+        corresponding local transaction will be guaranteed to have been
+        flushed to disk or not.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="pg-logical-emit-message" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_logical_emit_message</primary>
+        </indexterm>
+        <function>pg_logical_emit_message</function> ( <parameter>transactional</parameter> <type>boolean</type>, <parameter>prefix</parameter> <type>text</type>, <parameter>content</parameter> <type>text</type> <optional>, <parameter>flush</parameter> <type>boolean</type> <literal>DEFAULT</literal> <literal>false</literal></optional> )
+        <returnvalue>pg_lsn</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>pg_logical_emit_message</function> ( <parameter>transactional</parameter> <type>boolean</type>, <parameter>prefix</parameter> <type>text</type>, <parameter>content</parameter> <type>bytea</type> <optional>, <parameter>flush</parameter> <type>boolean</type> <literal>DEFAULT</literal> <literal>false</literal></optional> )
+        <returnvalue>pg_lsn</returnvalue>
+       </para>
+       <para>
+        Emits a logical decoding message. This can be used to pass generic
+        messages to logical decoding plugins through
+        WAL. The <parameter>transactional</parameter> parameter specifies if
+        the message should be part of the current transaction, or if it should
+        be written immediately and decoded as soon as the logical decoder
+        reads the record. The <parameter>prefix</parameter> parameter is a
+        textual prefix that can be used by logical decoding plugins to easily
+        recognize messages that are interesting for them.
+        The <parameter>content</parameter> parameter is the content of the
+        message, given either in text or binary form.
+        The <parameter>flush</parameter> parameter (default set to
+        <literal>false</literal>) controls if the message is immediately
+        flushed to WAL or not. <parameter>flush</parameter> has no effect
+        with <parameter>transactional</parameter>, as the message's WAL
+        record is flushed along with its transaction.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="pg-sync-replication-slots" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_sync_replication_slots</primary>
+        </indexterm>
+        <function>pg_sync_replication_slots</function> ()
+        <returnvalue>void</returnvalue>
+       </para>
+       <para>
+        Synchronize the logical failover replication slots from the primary
+        server to the standby server. This function can only be executed on the
+        standby server. Temporary synced slots, if any, cannot be used for
+        logical decoding and must be dropped after promotion. See
+        <xref linkend="logicaldecoding-replication-slots-synchronization"/> for details.
+        Note that this function is primarily intended for testing and
+        debugging purposes and should be used with caution. Additionally,
+        this function cannot be executed if
+        <link linkend="guc-sync-replication-slots"><varname>
+        sync_replication_slots</varname></link> is enabled and the slotsync
+        worker is already running to perform the synchronization of slots.
+       </para>
+
+       <caution>
+        <para>
+          If, after executing the function,
+          <link linkend="guc-hot-standby-feedback">
+          <varname>hot_standby_feedback</varname></link> is disabled on
+          the standby or the physical slot configured in
+          <link linkend="guc-primary-slot-name">
+          <varname>primary_slot_name</varname></link> is
+          removed, then it is possible that the necessary rows of the
+          synchronized slot will be removed by the VACUUM process on the primary
+          server, resulting in the synchronized slot becoming invalidated.
+        </para>
+       </caution>
+      </entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
+  </sect2>
+
+  <sect2 id="functions-admin-dbobject">
+   <title>Database Object Management Functions</title>
+
+   <para>
+    The functions shown in <xref linkend="functions-admin-dbsize"/> calculate
+    the disk space usage of database objects, or assist in presentation
+    or understanding of usage results.  <literal>bigint</literal> results
+    are measured in bytes.  If an OID that does
+    not represent an existing object is passed to one of these
+    functions, <literal>NULL</literal> is returned.
+   </para>
+
+   <table id="functions-admin-dbsize">
+    <title>Database Object Size Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_column_size</primary>
+        </indexterm>
+        <function>pg_column_size</function> ( <type>"any"</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Shows the number of bytes used to store any individual data value.  If
+        applied directly to a table column value, this reflects any
+        compression that was done.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_column_compression</primary>
+        </indexterm>
+        <function>pg_column_compression</function> ( <type>"any"</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Shows the compression algorithm that was used to compress
+        an individual variable-length value. Returns <literal>NULL</literal>
+        if the value is not compressed.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_column_toast_chunk_id</primary>
+        </indexterm>
+        <function>pg_column_toast_chunk_id</function> ( <type>"any"</type> )
+        <returnvalue>oid</returnvalue>
+       </para>
+       <para>
+        Shows the <structfield>chunk_id</structfield> of an on-disk
+        <acronym>TOAST</acronym>ed value.  Returns <literal>NULL</literal>
+        if the value is un-<acronym>TOAST</acronym>ed or not on-disk.  See
+        <xref linkend="storage-toast"/> for more information about
+        <acronym>TOAST</acronym>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_database_size</primary>
+        </indexterm>
+        <function>pg_database_size</function> ( <type>name</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>pg_database_size</function> ( <type>oid</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Computes the total disk space used by the database with the specified
+        name or OID.  To use this function, you must
+        have <literal>CONNECT</literal> privilege on the specified database
+        (which is granted by default) or have privileges of
+        the <literal>pg_read_all_stats</literal> role.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_indexes_size</primary>
+        </indexterm>
+        <function>pg_indexes_size</function> ( <type>regclass</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Computes the total disk space used by indexes attached to the
+        specified table.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_relation_size</primary>
+        </indexterm>
+        <function>pg_relation_size</function> ( <parameter>relation</parameter> <type>regclass</type> <optional>, <parameter>fork</parameter> <type>text</type> </optional> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Computes the disk space used by one <quote>fork</quote> of the
+        specified relation.  (Note that for most purposes it is more
+        convenient to use the higher-level
+        functions <function>pg_total_relation_size</function>
+        or <function>pg_table_size</function>, which sum the sizes of all
+        forks.)  With one argument, this returns the size of the main data
+        fork of the relation.  The second argument can be provided to specify
+        which fork to examine:
+        <itemizedlist spacing="compact">
+         <listitem>
+          <para>
+           <literal>main</literal> returns the size of the main
+           data fork of the relation.
+          </para>
+         </listitem>
+         <listitem>
+          <para>
+           <literal>fsm</literal> returns the size of the Free Space Map
+           (see <xref linkend="storage-fsm"/>) associated with the relation.
+          </para>
+         </listitem>
+         <listitem>
+          <para>
+           <literal>vm</literal> returns the size of the Visibility Map
+           (see <xref linkend="storage-vm"/>) associated with the relation.
+          </para>
+         </listitem>
+         <listitem>
+          <para>
+           <literal>init</literal> returns the size of the initialization
+           fork, if any, associated with the relation.
+          </para>
+         </listitem>
+        </itemizedlist>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_size_bytes</primary>
+        </indexterm>
+        <function>pg_size_bytes</function> ( <type>text</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Converts a size in human-readable format (as returned
+        by <function>pg_size_pretty</function>) into bytes.  Valid units are
+        <literal>bytes</literal>, <literal>B</literal>, <literal>kB</literal>,
+        <literal>MB</literal>, <literal>GB</literal>, <literal>TB</literal>,
+        and <literal>PB</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_size_pretty</primary>
+        </indexterm>
+        <function>pg_size_pretty</function> ( <type>bigint</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>pg_size_pretty</function> ( <type>numeric</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts a size in bytes into a more easily human-readable format with
+        size units (bytes, kB, MB, GB, TB, or PB as appropriate).  Note that the
+        units are powers of 2 rather than powers of 10, so 1kB is 1024 bytes,
+        1MB is 1024<superscript>2</superscript> = 1048576 bytes, and so on.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_table_size</primary>
+        </indexterm>
+        <function>pg_table_size</function> ( <type>regclass</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Computes the disk space used by the specified table, excluding indexes
+        (but including its TOAST table if any, free space map, and visibility
+        map).
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_tablespace_size</primary>
+        </indexterm>
+        <function>pg_tablespace_size</function> ( <type>name</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>pg_tablespace_size</function> ( <type>oid</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Computes the total disk space used in the tablespace with the
+        specified name or OID. To use this function, you must
+        have <literal>CREATE</literal> privilege on the specified tablespace
+        or have privileges of the <literal>pg_read_all_stats</literal> role,
+        unless it is the default tablespace for the current database.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_total_relation_size</primary>
+        </indexterm>
+        <function>pg_total_relation_size</function> ( <type>regclass</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Computes the total disk space used by the specified table, including
+        all indexes and <acronym>TOAST</acronym> data.  The result is
+        equivalent to <function>pg_table_size</function>
+        <literal>+</literal> <function>pg_indexes_size</function>.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    The functions above that operate on tables or indexes accept a
+    <type>regclass</type> argument, which is simply the OID of the table or index
+    in the <structname>pg_class</structname> system catalog.  You do not have to look up
+    the OID by hand, however, since the <type>regclass</type> data type's input
+    converter will do the work for you.  See <xref linkend="datatype-oid"/>
+    for details.
+   </para>
+
+   <para>
+    The functions shown in <xref linkend="functions-admin-dblocation"/> assist
+    in identifying the specific disk files associated with database objects.
+   </para>
+
+   <table id="functions-admin-dblocation">
+    <title>Database Object Location Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_relation_filenode</primary>
+        </indexterm>
+        <function>pg_relation_filenode</function> ( <parameter>relation</parameter> <type>regclass</type> )
+        <returnvalue>oid</returnvalue>
+       </para>
+       <para>
+        Returns the <quote>filenode</quote> number currently assigned to the
+        specified relation.  The filenode is the base component of the file
+        name(s) used for the relation (see
+        <xref linkend="storage-file-layout"/> for more information).
+        For most relations the result is the same as
+        <structname>pg_class</structname>.<structfield>relfilenode</structfield>,
+        but for certain system catalogs <structfield>relfilenode</structfield>
+        is zero and this function must be used to get the correct value.  The
+        function returns NULL if passed a relation that does not have storage,
+        such as a view.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_relation_filepath</primary>
+        </indexterm>
+        <function>pg_relation_filepath</function> ( <parameter>relation</parameter> <type>regclass</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the entire file path name (relative to the database cluster's
+        data directory, <varname>PGDATA</varname>) of the relation.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_filenode_relation</primary>
+        </indexterm>
+        <function>pg_filenode_relation</function> ( <parameter>tablespace</parameter> <type>oid</type>, <parameter>filenode</parameter> <type>oid</type> )
+        <returnvalue>regclass</returnvalue>
+       </para>
+       <para>
+        Returns a relation's OID given the tablespace OID and filenode it is
+        stored under.  This is essentially the inverse mapping of
+        <function>pg_relation_filepath</function>.  For a relation in the
+        database's default tablespace, the tablespace can be specified as zero.
+        Returns <literal>NULL</literal> if no relation in the current database
+        is associated with the given values.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    <xref linkend="functions-admin-collation"/> lists functions used to manage
+    collations.
+   </para>
+
+   <table id="functions-admin-collation">
+    <title>Collation Management Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_collation_actual_version</primary>
+        </indexterm>
+        <function>pg_collation_actual_version</function> ( <type>oid</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the actual version of the collation object as it is currently
+        installed in the operating system.  If this is different from the
+        value in
+        <structname>pg_collation</structname>.<structfield>collversion</structfield>,
+        then objects depending on the collation might need to be rebuilt.  See
+        also <xref linkend="sql-altercollation"/>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_database_collation_actual_version</primary>
+        </indexterm>
+        <function>pg_database_collation_actual_version</function> ( <type>oid</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the actual version of the database's collation as it is currently
+        installed in the operating system.  If this is different from the
+        value in
+        <structname>pg_database</structname>.<structfield>datcollversion</structfield>,
+        then objects depending on the collation might need to be rebuilt.  See
+        also <xref linkend="sql-alterdatabase"/>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_import_system_collations</primary>
+        </indexterm>
+        <function>pg_import_system_collations</function> ( <parameter>schema</parameter> <type>regnamespace</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Adds collations to the system
+        catalog <structname>pg_collation</structname> based on all the locales
+        it finds in the operating system.  This is
+        what <command>initdb</command> uses; see
+        <xref linkend="collation-managing"/> for more details.  If additional
+        locales are installed into the operating system later on, this
+        function can be run again to add collations for the new locales.
+        Locales that match existing entries
+        in <structname>pg_collation</structname> will be skipped.  (But
+        collation objects based on locales that are no longer present in the
+        operating system are not removed by this function.)
+        The <parameter>schema</parameter> parameter would typically
+        be <literal>pg_catalog</literal>, but that is not a requirement; the
+        collations could be installed into some other schema as well.  The
+        function returns the number of new collation objects it created.
+        Use of this function is restricted to superusers.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    <xref linkend="functions-admin-statsmod"/> lists functions used to
+    manipulate statistics.
+    These functions cannot be executed during recovery.
+    <warning>
+     <para>
+      Changes made by these statistics manipulation functions are likely to be
+      overwritten by <link linkend="autovacuum">autovacuum</link> (or manual
+      <command>VACUUM</command> or <command>ANALYZE</command>) and should be
+      considered temporary.
+     </para>
+    </warning>
+   </para>
+
+   <table id="functions-admin-statsmod">
+    <title>Database Object Statistics Manipulation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_restore_relation_stats</primary>
+        </indexterm>
+        <function>pg_restore_relation_stats</function> (
+        <literal>VARIADIC</literal> <parameter>kwargs</parameter> <type>"any"</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+        <para>
+         Updates table-level statistics.  Ordinarily, these statistics are
+         collected automatically or updated as a part of <xref
+         linkend="sql-vacuum"/> or <xref linkend="sql-analyze"/>, so it's not
+         necessary to call this function.  However, it is useful after a
+         restore to enable the optimizer to choose better plans if
+         <command>ANALYZE</command> has not been run yet.
+        </para>
+        <para>
+         The tracked statistics may change from version to version, so
+         arguments are passed as pairs of <replaceable>argname</replaceable>
+         and <replaceable>argvalue</replaceable> in the form:
+<programlisting>
+SELECT pg_restore_relation_stats(
+    '<replaceable>arg1name</replaceable>', '<replaceable>arg1value</replaceable>'::<replaceable>arg1type</replaceable>,
+    '<replaceable>arg2name</replaceable>', '<replaceable>arg2value</replaceable>'::<replaceable>arg2type</replaceable>,
+    '<replaceable>arg3name</replaceable>', '<replaceable>arg3value</replaceable>'::<replaceable>arg3type</replaceable>);
+</programlisting>
+        </para>
+        <para>
+         For example, to set the <structfield>relpages</structfield> and
+         <structfield>reltuples</structfield> values for the table
+         <structname>mytable</structname>:
+<programlisting>
+SELECT pg_restore_relation_stats(
+    'schemaname', 'myschema',
+    'relname',    'mytable',
+    'relpages',   173::integer,
+    'reltuples',  10000::real);
+</programlisting>
+        </para>
+        <para>
+         The arguments <literal>schemaname</literal> and
+         <literal>relname</literal> are required, and specify the table. Other
+         arguments are the names and values of statistics corresponding to
+         certain columns in <link
+         linkend="catalog-pg-class"><structname>pg_class</structname></link>.
+         The currently-supported relation statistics are
+         <literal>relpages</literal> with a value of type
+         <type>integer</type>, <literal>reltuples</literal> with a value of
+         type <type>real</type>, <literal>relallvisible</literal> with a value
+         of type <type>integer</type>, and <literal>relallfrozen</literal>
+         with a value of type <type>integer</type>.
+        </para>
+        <para>
+         Additionally, this function accepts argument name
+         <literal>version</literal> of type <type>integer</type>, which
+         specifies the server version from which the statistics originated.
+         This is anticipated to be helpful in porting statistics from older
+         versions of <productname>PostgreSQL</productname>.
+        </para>
+        <para>
+         Minor errors are reported as a <literal>WARNING</literal> and
+         ignored, and remaining statistics will still be restored. If all
+         specified statistics are successfully restored, returns
+         <literal>true</literal>, otherwise <literal>false</literal>.
+        </para>
+        <para>
+         The caller must have the <literal>MAINTAIN</literal> privilege on the
+         table or be the owner of the database.
+        </para>
+       </entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry">
+        <para role="func_signature">
+         <indexterm>
+          <primary>pg_clear_relation_stats</primary>
+         </indexterm>
+         <function>pg_clear_relation_stats</function> ( <parameter>schemaname</parameter> <type>text</type>, <parameter>relname</parameter> <type>text</type> )
+         <returnvalue>void</returnvalue>
+        </para>
+        <para>
+         Clears table-level statistics for the given relation, as though the
+         table was newly created.
+        </para>
+        <para>
+         The caller must have the <literal>MAINTAIN</literal> privilege on the
+         table or be the owner of the database.
+        </para>
+       </entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_restore_attribute_stats</primary>
+        </indexterm>
+        <function>pg_restore_attribute_stats</function> (
+        <literal>VARIADIC</literal> <parameter>kwargs</parameter> <type>"any"</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+        <para>
+         Creates or updates column-level statistics.  Ordinarily, these
+         statistics are collected automatically or updated as a part of <xref
+         linkend="sql-vacuum"/> or <xref linkend="sql-analyze"/>, so it's not
+         necessary to call this function.  However, it is useful after a
+         restore to enable the optimizer to choose better plans if
+         <command>ANALYZE</command> has not been run yet.
+        </para>
+        <para>
+         The tracked statistics may change from version to version, so
+         arguments are passed as pairs of <replaceable>argname</replaceable>
+         and <replaceable>argvalue</replaceable> in the form:
+<programlisting>
+SELECT pg_restore_attribute_stats(
+    '<replaceable>arg1name</replaceable>', '<replaceable>arg1value</replaceable>'::<replaceable>arg1type</replaceable>,
+    '<replaceable>arg2name</replaceable>', '<replaceable>arg2value</replaceable>'::<replaceable>arg2type</replaceable>,
+    '<replaceable>arg3name</replaceable>', '<replaceable>arg3value</replaceable>'::<replaceable>arg3type</replaceable>);
+</programlisting>
+        </para>
+        <para>
+         For example, to set the <structfield>avg_width</structfield> and
+         <structfield>null_frac</structfield> values for the attribute
+         <structfield>col1</structfield> of the table
+         <structname>mytable</structname>:
+<programlisting>
+SELECT pg_restore_attribute_stats(
+    'schemaname', 'myschema',
+    'relname',    'mytable',
+    'attname',    'col1',
+    'inherited',  false,
+    'avg_width',  125::integer,
+    'null_frac',  0.5::real);
+</programlisting>
+        </para>
+        <para>
+         The required arguments are <literal>schemaname</literal> and
+         <literal>relname</literal> with a value of type <type>text</type>
+         which specify the table; either <literal>attname</literal> with a
+         value of type <type>text</type> or <literal>attnum</literal> with a
+         value of type <type>smallint</type>, which specifies the column; and
+         <literal>inherited</literal>, which specifies whether the statistics
+         include values from child tables.  Other arguments are the names and
+         values of statistics corresponding to columns in <link
+         linkend="view-pg-stats"><structname>pg_stats</structname></link>.
+        </para>
+        <para>
+         Additionally, this function accepts argument name
+         <literal>version</literal> of type <type>integer</type>, which
+         specifies the server version from which the statistics originated.
+         This is anticipated to be helpful in porting statistics from older
+         versions of <productname>PostgreSQL</productname>.
+        </para>
+        <para>
+         Minor errors are reported as a <literal>WARNING</literal> and
+         ignored, and remaining statistics will still be restored. If all
+         specified statistics are successfully restored, returns
+         <literal>true</literal>, otherwise <literal>false</literal>.
+        </para>
+        <para>
+         The caller must have the <literal>MAINTAIN</literal> privilege on the
+         table or be the owner of the database.
+        </para>
+       </entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry">
+        <para role="func_signature">
+         <indexterm>
+          <primary>pg_clear_attribute_stats</primary>
+         </indexterm>
+         <function>pg_clear_attribute_stats</function> (
+         <parameter>schemaname</parameter> <type>text</type>,
+         <parameter>relname</parameter> <type>text</type>,
+         <parameter>attname</parameter> <type>text</type>,
+         <parameter>inherited</parameter> <type>boolean</type> )
+         <returnvalue>void</returnvalue>
+        </para>
+        <para>
+         Clears column-level statistics for the given relation and
+         attribute, as though the table was newly created.
+        </para>
+        <para>
+         The caller must have the <literal>MAINTAIN</literal> privilege on
+         the table or be the owner of the database.
+        </para>
+       </entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    <xref linkend="functions-info-partition"/> lists functions that provide
+    information about the structure of partitioned tables.
+   </para>
+
+   <table id="functions-info-partition">
+    <title>Partitioning Information Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_partition_tree</primary>
+        </indexterm>
+        <function>pg_partition_tree</function> ( <type>regclass</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>relid</parameter> <type>regclass</type>,
+        <parameter>parentrelid</parameter> <type>regclass</type>,
+        <parameter>isleaf</parameter> <type>boolean</type>,
+        <parameter>level</parameter> <type>integer</type> )
+       </para>
+       <para>
+        Lists the tables or indexes in the partition tree of the
+        given partitioned table or partitioned index, with one row for each
+        partition.  Information provided includes the OID of the partition,
+        the OID of its immediate parent, a boolean value telling if the
+        partition is a leaf, and an integer telling its level in the hierarchy.
+        The level value is 0 for the input table or index, 1 for its
+        immediate child partitions, 2 for their partitions, and so on.
+        Returns no rows if the relation does not exist or is not a partition
+        or partitioned table.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_partition_ancestors</primary>
+        </indexterm>
+        <function>pg_partition_ancestors</function> ( <type>regclass</type> )
+        <returnvalue>setof regclass</returnvalue>
+       </para>
+       <para>
+        Lists the ancestor relations of the given partition,
+        including the relation itself.  Returns no rows if the relation
+        does not exist or is not a partition or partitioned table.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_partition_root</primary>
+        </indexterm>
+        <function>pg_partition_root</function> ( <type>regclass</type> )
+        <returnvalue>regclass</returnvalue>
+       </para>
+       <para>
+        Returns the top-most parent of the partition tree to which the given
+        relation belongs.  Returns <literal>NULL</literal> if the relation
+        does not exist or is not a partition or partitioned table.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    For example, to check the total size of the data contained in a
+    partitioned table <structname>measurement</structname>, one could use the
+    following query:
+<programlisting>
+SELECT pg_size_pretty(sum(pg_relation_size(relid))) AS total_size
+  FROM pg_partition_tree('measurement');
+</programlisting>
+   </para>
+
+  </sect2>
+
+  <sect2 id="functions-admin-index">
+   <title>Index Maintenance Functions</title>
+
+   <para>
+    <xref linkend="functions-admin-index-table"/> shows the functions
+    available for index maintenance tasks.  (Note that these maintenance
+    tasks are normally done automatically by autovacuum; use of these
+    functions is only required in special cases.)
+    These functions cannot be executed during recovery.
+    Use of these functions is restricted to superusers and the owner
+    of the given index.
+   </para>
+
+   <table id="functions-admin-index-table">
+    <title>Index Maintenance Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>brin_summarize_new_values</primary>
+        </indexterm>
+        <function>brin_summarize_new_values</function> ( <parameter>index</parameter> <type>regclass</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Scans the specified BRIN index to find page ranges in the base table
+        that are not currently summarized by the index; for any such range it
+        creates a new summary index tuple by scanning those table pages.
+        Returns the number of new page range summaries that were inserted
+        into the index.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>brin_summarize_range</primary>
+        </indexterm>
+        <function>brin_summarize_range</function> ( <parameter>index</parameter> <type>regclass</type>, <parameter>blockNumber</parameter> <type>bigint</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Summarizes the page range covering the given block, if not already
+        summarized.  This is
+        like <function>brin_summarize_new_values</function> except that it
+        only processes the page range that covers the given table block number.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>brin_desummarize_range</primary>
+        </indexterm>
+        <function>brin_desummarize_range</function> ( <parameter>index</parameter> <type>regclass</type>, <parameter>blockNumber</parameter> <type>bigint</type> )
+        <returnvalue>void</returnvalue>
+       </para>
+       <para>
+        Removes the BRIN index tuple that summarizes the page range covering
+        the given table block, if there is one.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>gin_clean_pending_list</primary>
+        </indexterm>
+        <function>gin_clean_pending_list</function> ( <parameter>index</parameter> <type>regclass</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Cleans up the <quote>pending</quote> list of the specified GIN index
+        by moving entries in it, in bulk, to the main GIN data structure.
+        Returns the number of pages removed from the pending list.
+        If the argument is a GIN index built with
+        the <literal>fastupdate</literal> option disabled, no cleanup happens
+        and the result is zero, because the index doesn't have a pending list.
+        See <xref linkend="gin-fast-update"/> and <xref linkend="gin-tips"/>
+        for details about the pending list and <literal>fastupdate</literal>
+        option.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  </sect2>
+
+  <sect2 id="functions-admin-genfile">
+   <title>Generic File Access Functions</title>
+
+   <para>
+    The functions shown in <xref
+    linkend="functions-admin-genfile-table"/> provide native access to
+    files on the machine hosting the server. Only files within the
+    database cluster directory and the <varname>log_directory</varname> can be
+    accessed, unless the user is a superuser or is granted the role
+    <literal>pg_read_server_files</literal>.  Use a relative path for files in
+    the cluster directory, and a path matching the <varname>log_directory</varname>
+    configuration setting for log files.
+   </para>
+
+   <para>
+    Note that granting users the EXECUTE privilege on
+    <function>pg_read_file()</function>, or related functions, allows them the
+    ability to read any file on the server that the database server process can
+    read; these functions bypass all in-database privilege checks.  This means
+    that, for example, a user with such access is able to read the contents of
+    the <structname>pg_authid</structname> table where authentication
+    information is stored, as well as read any table data in the database.
+    Therefore, granting access to these functions should be carefully
+    considered.
+   </para>
+
+   <para>
+    When granting privilege on these functions, note that the table entries
+    showing optional parameters are mostly implemented as several physical
+    functions with different parameter lists.  Privilege must be granted
+    separately on each such function, if it is to be
+    used.  <application>psql</application>'s <command>\df</command> command
+    can be useful to check what the actual function signatures are.
+   </para>
+
+   <para>
+    Some of these functions take an optional <parameter>missing_ok</parameter>
+    parameter, which specifies the behavior when the file or directory does
+    not exist.  If <literal>true</literal>, the function
+    returns <literal>NULL</literal> or an empty result set, as appropriate.
+    If <literal>false</literal>, an error is raised.  (Failure conditions
+    other than <quote>file not found</quote> are reported as errors in any
+    case.)  The default is <literal>false</literal>.
+   </para>
+
+   <table id="functions-admin-genfile-table">
+    <title>Generic File Access Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_ls_dir</primary>
+        </indexterm>
+        <function>pg_ls_dir</function> ( <parameter>dirname</parameter> <type>text</type> <optional>, <parameter>missing_ok</parameter> <type>boolean</type>, <parameter>include_dot_dirs</parameter> <type>boolean</type> </optional> )
+        <returnvalue>setof text</returnvalue>
+       </para>
+       <para>
+        Returns the names of all files (and directories and other special
+        files) in the specified
+        directory. The <parameter>include_dot_dirs</parameter> parameter
+        indicates whether <quote>.</quote> and <quote>..</quote> are to be
+        included in the result set; the default is to exclude them.  Including
+        them can be useful when <parameter>missing_ok</parameter>
+        is <literal>true</literal>, to distinguish an empty directory from a
+        non-existent directory.
+       </para>
+       <para>
+        This function is restricted to superusers by default, but other users
+        can be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_ls_logdir</primary>
+        </indexterm>
+        <function>pg_ls_logdir</function> ()
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>name</parameter> <type>text</type>,
+        <parameter>size</parameter> <type>bigint</type>,
+        <parameter>modification</parameter> <type>timestamp with time zone</type> )
+       </para>
+       <para>
+        Returns the name, size, and last modification time (mtime) of each
+        ordinary file in the server's log directory.  Filenames beginning with
+        a dot, directories, and other special files are excluded.
+       </para>
+       <para>
+        This function is restricted to superusers and roles with privileges of
+        the <literal>pg_monitor</literal> role by default, but other users can
+        be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_ls_waldir</primary>
+        </indexterm>
+        <function>pg_ls_waldir</function> ()
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>name</parameter> <type>text</type>,
+        <parameter>size</parameter> <type>bigint</type>,
+        <parameter>modification</parameter> <type>timestamp with time zone</type> )
+       </para>
+       <para>
+        Returns the name, size, and last modification time (mtime) of each
+        ordinary file in the server's write-ahead log (WAL) directory.
+        Filenames beginning with a dot, directories, and other special files
+        are excluded.
+       </para>
+       <para>
+        This function is restricted to superusers and roles with privileges of
+        the <literal>pg_monitor</literal> role by default, but other users can
+        be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_ls_logicalmapdir</primary>
+        </indexterm>
+        <function>pg_ls_logicalmapdir</function> ()
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>name</parameter> <type>text</type>,
+        <parameter>size</parameter> <type>bigint</type>,
+        <parameter>modification</parameter> <type>timestamp with time zone</type> )
+       </para>
+       <para>
+        Returns the name, size, and last modification time (mtime) of each
+        ordinary file in the server's <filename>pg_logical/mappings</filename>
+        directory. Filenames beginning with a dot, directories, and other
+        special files are excluded.
+       </para>
+       <para>
+        This function is restricted to superusers and members of
+        the <literal>pg_monitor</literal> role by default, but other users can
+        be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_ls_logicalsnapdir</primary>
+        </indexterm>
+        <function>pg_ls_logicalsnapdir</function> ()
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>name</parameter> <type>text</type>,
+        <parameter>size</parameter> <type>bigint</type>,
+        <parameter>modification</parameter> <type>timestamp with time zone</type> )
+       </para>
+       <para>
+        Returns the name, size, and last modification time (mtime) of each
+        ordinary file in the server's <filename>pg_logical/snapshots</filename>
+        directory. Filenames beginning with a dot, directories, and other
+        special files are excluded.
+       </para>
+       <para>
+        This function is restricted to superusers and members of
+        the <literal>pg_monitor</literal> role by default, but other users can
+        be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_ls_replslotdir</primary>
+        </indexterm>
+        <function>pg_ls_replslotdir</function> ( <parameter>slot_name</parameter> <type>text</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>name</parameter> <type>text</type>,
+        <parameter>size</parameter> <type>bigint</type>,
+        <parameter>modification</parameter> <type>timestamp with time zone</type> )
+       </para>
+       <para>
+        Returns the name, size, and last modification time (mtime) of each
+        ordinary file in the server's <filename>pg_replslot/slot_name</filename>
+        directory, where <parameter>slot_name</parameter> is the name of the
+        replication slot provided as input of the function. Filenames beginning
+        with a dot, directories, and other special files are excluded.
+       </para>
+       <para>
+        This function is restricted to superusers and members of
+        the <literal>pg_monitor</literal> role by default, but other users can
+        be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_ls_summariesdir</primary>
+        </indexterm>
+        <function>pg_ls_summariesdir</function> ()
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>name</parameter> <type>text</type>,
+        <parameter>size</parameter> <type>bigint</type>,
+        <parameter>modification</parameter> <type>timestamp with time zone</type> )
+       </para>
+       <para>
+        Returns the name, size, and last modification time (mtime) of each
+        ordinary file in the server's WAL summaries directory
+        (<filename>pg_wal/summaries</filename>).  Filenames beginning
+        with a dot, directories, and other special files are excluded.
+       </para>
+       <para>
+        This function is restricted to superusers and members of
+        the <literal>pg_monitor</literal> role by default, but other users can
+        be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_ls_archive_statusdir</primary>
+        </indexterm>
+        <function>pg_ls_archive_statusdir</function> ()
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>name</parameter> <type>text</type>,
+        <parameter>size</parameter> <type>bigint</type>,
+        <parameter>modification</parameter> <type>timestamp with time zone</type> )
+       </para>
+       <para>
+        Returns the name, size, and last modification time (mtime) of each
+        ordinary file in the server's WAL archive status directory
+        (<filename>pg_wal/archive_status</filename>).  Filenames beginning
+        with a dot, directories, and other special files are excluded.
+       </para>
+       <para>
+        This function is restricted to superusers and members of
+        the <literal>pg_monitor</literal> role by default, but other users can
+        be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+
+        <indexterm>
+         <primary>pg_ls_tmpdir</primary>
+        </indexterm>
+        <function>pg_ls_tmpdir</function> ( <optional> <parameter>tablespace</parameter> <type>oid</type> </optional> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>name</parameter> <type>text</type>,
+        <parameter>size</parameter> <type>bigint</type>,
+        <parameter>modification</parameter> <type>timestamp with time zone</type> )
+       </para>
+       <para>
+        Returns the name, size, and last modification time (mtime) of each
+        ordinary file in the temporary file directory for the
+        specified <parameter>tablespace</parameter>.
+        If <parameter>tablespace</parameter> is not provided,
+        the <literal>pg_default</literal> tablespace is examined.  Filenames
+        beginning with a dot, directories, and other special files are
+        excluded.
+       </para>
+       <para>
+        This function is restricted to superusers and members of
+        the <literal>pg_monitor</literal> role by default, but other users can
+        be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_read_file</primary>
+        </indexterm>
+        <function>pg_read_file</function> ( <parameter>filename</parameter> <type>text</type> <optional>, <parameter>offset</parameter> <type>bigint</type>, <parameter>length</parameter> <type>bigint</type> </optional> <optional>, <parameter>missing_ok</parameter> <type>boolean</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns all or part of a text file, starting at the
+        given byte <parameter>offset</parameter>, returning at
+        most <parameter>length</parameter> bytes (less if the end of file is
+        reached first).  If <parameter>offset</parameter> is negative, it is
+        relative to the end of the file.  If <parameter>offset</parameter>
+        and <parameter>length</parameter> are omitted, the entire file is
+        returned.  The bytes read from the file are interpreted as a string in
+        the database's encoding; an error is thrown if they are not valid in
+        that encoding.
+       </para>
+       <para>
+        This function is restricted to superusers by default, but other users
+        can be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_read_binary_file</primary>
+        </indexterm>
+        <function>pg_read_binary_file</function> ( <parameter>filename</parameter> <type>text</type> <optional>, <parameter>offset</parameter> <type>bigint</type>, <parameter>length</parameter> <type>bigint</type> </optional> <optional>, <parameter>missing_ok</parameter> <type>boolean</type> </optional> )
+        <returnvalue>bytea</returnvalue>
+       </para>
+       <para>
+        Returns all or part of a file.  This function is identical to
+        <function>pg_read_file</function> except that it can read arbitrary
+        binary data, returning the result as <type>bytea</type>
+        not <type>text</type>; accordingly, no encoding checks are performed.
+       </para>
+       <para>
+        This function is restricted to superusers by default, but other users
+        can be granted EXECUTE to run the function.
+       </para>
+       <para>
+        In combination with the <function>convert_from</function> function,
+        this function can be used to read a text file in a specified encoding
+        and convert to the database's encoding:
+<programlisting>
+SELECT convert_from(pg_read_binary_file('file_in_utf8.txt'), 'UTF8');
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_stat_file</primary>
+        </indexterm>
+        <function>pg_stat_file</function> ( <parameter>filename</parameter> <type>text</type> <optional>, <parameter>missing_ok</parameter> <type>boolean</type> </optional> )
+        <returnvalue>record</returnvalue>
+        ( <parameter>size</parameter> <type>bigint</type>,
+        <parameter>access</parameter> <type>timestamp with time zone</type>,
+        <parameter>modification</parameter> <type>timestamp with time zone</type>,
+        <parameter>change</parameter> <type>timestamp with time zone</type>,
+        <parameter>creation</parameter> <type>timestamp with time zone</type>,
+        <parameter>isdir</parameter> <type>boolean</type> )
+       </para>
+       <para>
+        Returns a record containing the file's size, last access time stamp,
+        last modification time stamp, last file status change time stamp (Unix
+        platforms only), file creation time stamp (Windows only), and a flag
+        indicating if it is a directory.
+       </para>
+       <para>
+        This function is restricted to superusers by default, but other users
+        can be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
+  </sect2>
+
+  <sect2 id="functions-advisory-locks">
+   <title>Advisory Lock Functions</title>
+
+   <para>
+    The functions shown in <xref linkend="functions-advisory-locks-table"/>
+    manage advisory locks.  For details about proper use of these functions,
+    see <xref linkend="advisory-locks"/>.
+   </para>
+
+   <para>
+    All these functions are intended to be used to lock application-defined
+    resources, which can be identified either by a single 64-bit key value or
+    two 32-bit key values (note that these two key spaces do not overlap).
+    If another session already holds a conflicting lock on the same resource
+    identifier, the functions will either wait until the resource becomes
+    available, or return a <literal>false</literal> result, as appropriate for
+    the function.
+    Locks can be either shared or exclusive: a shared lock does not conflict
+    with other shared locks on the same resource, only with exclusive locks.
+    Locks can be taken at session level (so that they are held until released
+    or the session ends) or at transaction level (so that they are held until
+    the current transaction ends; there is no provision for manual release).
+    Multiple session-level lock requests stack, so that if the same resource
+    identifier is locked three times there must then be three unlock requests
+    to release the resource in advance of session end.
+   </para>
+
+   <table id="functions-advisory-locks-table">
+    <title>Advisory Lock Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_advisory_lock</primary>
+        </indexterm>
+        <function>pg_advisory_lock</function> ( <parameter>key</parameter> <type>bigint</type> )
+        <returnvalue>void</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>pg_advisory_lock</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
+        <returnvalue>void</returnvalue>
+       </para>
+       <para>
+        Obtains an exclusive session-level advisory lock, waiting if necessary.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_advisory_lock_shared</primary>
+        </indexterm>
+        <function>pg_advisory_lock_shared</function> ( <parameter>key</parameter> <type>bigint</type> )
+        <returnvalue>void</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>pg_advisory_lock_shared</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
+        <returnvalue>void</returnvalue>
+       </para>
+       <para>
+        Obtains a shared session-level advisory lock, waiting if necessary.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_advisory_unlock</primary>
+        </indexterm>
+        <function>pg_advisory_unlock</function> ( <parameter>key</parameter> <type>bigint</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>pg_advisory_unlock</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Releases a previously-acquired exclusive session-level advisory lock.
+        Returns <literal>true</literal> if the lock is successfully released.
+        If the lock was not held, <literal>false</literal> is returned, and in
+        addition, an SQL warning will be reported by the server.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_advisory_unlock_all</primary>
+        </indexterm>
+        <function>pg_advisory_unlock_all</function> ()
+        <returnvalue>void</returnvalue>
+       </para>
+       <para>
+        Releases all session-level advisory locks held by the current session.
+        (This function is implicitly invoked at session end, even if the
+        client disconnects ungracefully.)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_advisory_unlock_shared</primary>
+        </indexterm>
+        <function>pg_advisory_unlock_shared</function> ( <parameter>key</parameter> <type>bigint</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>pg_advisory_unlock_shared</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Releases a previously-acquired shared session-level advisory lock.
+        Returns <literal>true</literal> if the lock is successfully released.
+        If the lock was not held, <literal>false</literal> is returned, and in
+        addition, an SQL warning will be reported by the server.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_advisory_xact_lock</primary>
+        </indexterm>
+        <function>pg_advisory_xact_lock</function> ( <parameter>key</parameter> <type>bigint</type> )
+        <returnvalue>void</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>pg_advisory_xact_lock</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
+        <returnvalue>void</returnvalue>
+       </para>
+       <para>
+        Obtains an exclusive transaction-level advisory lock, waiting if
+        necessary.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_advisory_xact_lock_shared</primary>
+        </indexterm>
+        <function>pg_advisory_xact_lock_shared</function> ( <parameter>key</parameter> <type>bigint</type> )
+        <returnvalue>void</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>pg_advisory_xact_lock_shared</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
+        <returnvalue>void</returnvalue>
+       </para>
+       <para>
+        Obtains a shared transaction-level advisory lock, waiting if
+        necessary.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_try_advisory_lock</primary>
+        </indexterm>
+        <function>pg_try_advisory_lock</function> ( <parameter>key</parameter> <type>bigint</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>pg_try_advisory_lock</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Obtains an exclusive session-level advisory lock if available.
+        This will either obtain the lock immediately and
+        return <literal>true</literal>, or return <literal>false</literal>
+        without waiting if the lock cannot be acquired immediately.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_try_advisory_lock_shared</primary>
+        </indexterm>
+        <function>pg_try_advisory_lock_shared</function> ( <parameter>key</parameter> <type>bigint</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>pg_try_advisory_lock_shared</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Obtains a shared session-level advisory lock if available.
+        This will either obtain the lock immediately and
+        return <literal>true</literal>, or return <literal>false</literal>
+        without waiting if the lock cannot be acquired immediately.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_try_advisory_xact_lock</primary>
+        </indexterm>
+        <function>pg_try_advisory_xact_lock</function> ( <parameter>key</parameter> <type>bigint</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>pg_try_advisory_xact_lock</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Obtains an exclusive transaction-level advisory lock if available.
+        This will either obtain the lock immediately and
+        return <literal>true</literal>, or return <literal>false</literal>
+        without waiting if the lock cannot be acquired immediately.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_try_advisory_xact_lock_shared</primary>
+        </indexterm>
+        <function>pg_try_advisory_xact_lock_shared</function> ( <parameter>key</parameter> <type>bigint</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>pg_try_advisory_xact_lock_shared</function> ( <parameter>key1</parameter> <type>integer</type>, <parameter>key2</parameter> <type>integer</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Obtains a shared transaction-level advisory lock if available.
+        This will either obtain the lock immediately and
+        return <literal>true</literal>, or return <literal>false</literal>
+        without waiting if the lock cannot be acquired immediately.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  </sect2>
+
+  </sect1>
diff --git a/doc/src/sgml/func/func-aggregate.sgml b/doc/src/sgml/func/func-aggregate.sgml
new file mode 100644
index 0000000000000..f50b692516b62
--- /dev/null
+++ b/doc/src/sgml/func/func-aggregate.sgml
@@ -0,0 +1,1418 @@
+ <sect1 id="functions-aggregate">
+  <title>Aggregate Functions</title>
+
+  <indexterm zone="functions-aggregate">
+   <primary>aggregate function</primary>
+   <secondary>built-in</secondary>
+  </indexterm>
+
+  <para>
+   <firstterm>Aggregate functions</firstterm> compute a single result
+   from a set of input values.  The built-in general-purpose aggregate
+   functions are listed in <xref linkend="functions-aggregate-table"/>
+   while statistical aggregates are in <xref
+   linkend="functions-aggregate-statistics-table"/>.
+   The built-in within-group ordered-set aggregate functions
+   are listed in <xref linkend="functions-orderedset-table"/>
+   while the built-in within-group hypothetical-set ones are in <xref
+   linkend="functions-hypothetical-table"/>.  Grouping operations,
+   which are closely related to aggregate functions, are listed in
+   <xref linkend="functions-grouping-table"/>.
+   The special syntax considerations for aggregate
+   functions are explained in <xref linkend="syntax-aggregates"/>.
+   Consult <xref linkend="tutorial-agg"/> for additional introductory
+   information.
+  </para>
+
+  <para>
+   Aggregate functions that support <firstterm>Partial Mode</firstterm>
+   are eligible to participate in various optimizations, such as parallel
+   aggregation.
+  </para>
+
+  <para>
+   While all aggregates below accept an optional
+   <literal>ORDER BY</literal> clause (as outlined in <xref
+   linkend="syntax-aggregates"/>), the clause has only been added to
+   aggregates whose output is affected by ordering.
+  </para>
+
+   <table id="functions-aggregate-table">
+    <title>General-Purpose Aggregate Functions</title>
+    <tgroup cols="2">
+     <colspec colname="col1" colwidth="10*"/>
+     <colspec colname="col2" colwidth="1*"/>
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+       <entry>Partial Mode</entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>any_value</primary>
+        </indexterm>
+        <function>any_value</function> ( <type>anyelement</type> )
+        <returnvalue><replaceable>same as input type</replaceable></returnvalue>
+       </para>
+       <para>
+        Returns an arbitrary value from the non-null input values.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_agg</primary>
+        </indexterm>
+        <function>array_agg</function> ( <type>anynonarray</type> <literal>ORDER BY</literal> <literal>input_sort_columns</literal> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Collects all the input values, including nulls, into an array.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>array_agg</function> ( <type>anyarray</type> <literal>ORDER BY</literal> <literal>input_sort_columns</literal> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Concatenates all the input arrays into an array of one higher
+        dimension.  (The inputs must all have the same dimensionality, and
+        cannot be empty or null.)
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>average</primary>
+        </indexterm>
+        <indexterm>
+         <primary>avg</primary>
+        </indexterm>
+        <function>avg</function> ( <type>smallint</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>avg</function> ( <type>integer</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>avg</function> ( <type>bigint</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>avg</function> ( <type>numeric</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>avg</function> ( <type>real</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>avg</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>avg</function> ( <type>interval</type> )
+        <returnvalue>interval</returnvalue>
+       </para>
+       <para>
+        Computes the average (arithmetic mean) of all the non-null input
+        values.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>bit_and</primary>
+        </indexterm>
+        <function>bit_and</function> ( <type>smallint</type> )
+        <returnvalue>smallint</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>bit_and</function> ( <type>integer</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>bit_and</function> ( <type>bigint</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>bit_and</function> ( <type>bit</type> )
+        <returnvalue>bit</returnvalue>
+       </para>
+       <para>
+        Computes the bitwise AND of all non-null input values.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>bit_or</primary>
+        </indexterm>
+        <function>bit_or</function> ( <type>smallint</type> )
+        <returnvalue>smallint</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>bit_or</function> ( <type>integer</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>bit_or</function> ( <type>bigint</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>bit_or</function> ( <type>bit</type> )
+        <returnvalue>bit</returnvalue>
+       </para>
+       <para>
+        Computes the bitwise OR of all non-null input values.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>bit_xor</primary>
+        </indexterm>
+        <function>bit_xor</function> ( <type>smallint</type> )
+        <returnvalue>smallint</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>bit_xor</function> ( <type>integer</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>bit_xor</function> ( <type>bigint</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>bit_xor</function> ( <type>bit</type> )
+        <returnvalue>bit</returnvalue>
+       </para>
+       <para>
+        Computes the bitwise exclusive OR of all non-null input values.
+        Can be useful as a checksum for an unordered set of values.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>bool_and</primary>
+        </indexterm>
+        <function>bool_and</function> ( <type>boolean</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Returns true if all non-null input values are true, otherwise false.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>bool_or</primary>
+        </indexterm>
+        <function>bool_or</function> ( <type>boolean</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Returns true if any non-null input value is true, otherwise false.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>count</primary>
+        </indexterm>
+        <function>count</function> ( <literal>*</literal> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Computes the number of input rows.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>count</function> ( <type>"any"</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Computes the number of input rows in which the input value is not
+        null.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>every</primary>
+        </indexterm>
+        <function>every</function> ( <type>boolean</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        This is the SQL standard's equivalent to <function>bool_and</function>.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_agg</primary>
+        </indexterm>
+        <function>json_agg</function> ( <type>anyelement</type> <literal>ORDER BY</literal> <literal>input_sort_columns</literal> )
+        <returnvalue>json</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_agg</primary>
+        </indexterm>
+        <function>jsonb_agg</function> ( <type>anyelement</type> <literal>ORDER BY</literal> <literal>input_sort_columns</literal> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Collects all the input values, including nulls, into a JSON array.
+        Values are converted to JSON as per <function>to_json</function>
+        or <function>to_jsonb</function>.
+       </para></entry>
+       <entry>No</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_agg_strict</primary>
+        </indexterm>
+        <function>json_agg_strict</function> ( <type>anyelement</type> )
+        <returnvalue>json</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_agg_strict</primary>
+        </indexterm>
+        <function>jsonb_agg_strict</function> ( <type>anyelement</type> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Collects all the input values, skipping nulls, into a JSON array.
+        Values are converted to JSON as per <function>to_json</function>
+        or <function>to_jsonb</function>.
+       </para></entry>
+       <entry>No</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm><primary>json_arrayagg</primary></indexterm>
+        <function>json_arrayagg</function> (
+        <optional> <replaceable>value_expression</replaceable> </optional>
+        <optional> <literal>ORDER BY</literal> <replaceable>sort_expression</replaceable> </optional>
+        <optional> { <literal>NULL</literal> | <literal>ABSENT</literal> } <literal>ON NULL</literal> </optional>
+        <optional> <literal>RETURNING</literal> <replaceable>data_type</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional> </optional>)
+       </para>
+       <para>
+        Behaves in the same way as <function>json_array</function>
+        but as an aggregate function so it only takes one
+        <replaceable>value_expression</replaceable> parameter.
+        If <literal>ABSENT ON NULL</literal> is specified, any NULL
+        values are omitted.
+        If <literal>ORDER BY</literal> is specified, the elements will
+        appear in the array in that order rather than in the input order.
+       </para>
+       <para>
+        <literal>SELECT json_arrayagg(v) FROM (VALUES(2),(1)) t(v)</literal>
+        <returnvalue>[2, 1]</returnvalue>
+       </para></entry>
+       <entry>No</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+         <indexterm><primary>json_objectagg</primary></indexterm>
+         <function>json_objectagg</function> (
+         <optional> { <replaceable>key_expression</replaceable> { <literal>VALUE</literal> | ':' } <replaceable>value_expression</replaceable> } </optional>
+         <optional> { <literal>NULL</literal> | <literal>ABSENT</literal> } <literal>ON NULL</literal> </optional>
+        <optional> { <literal>WITH</literal> | <literal>WITHOUT</literal> } <literal>UNIQUE</literal> <optional> <literal>KEYS</literal> </optional> </optional>
+        <optional> <literal>RETURNING</literal> <replaceable>data_type</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional> </optional>)
+        </para>
+        <para>
+         Behaves like <function>json_object</function><!-- xref -->, but as an
+         aggregate function, so it only takes one
+         <replaceable>key_expression</replaceable> and one
+         <replaceable>value_expression</replaceable> parameter.
+        </para>
+        <para>
+         <literal>SELECT json_objectagg(k:v) FROM (VALUES ('a'::text,current_date),('b',current_date + 1)) AS t(k,v)</literal>
+         <returnvalue>{ "a" : "2022-05-10", "b" : "2022-05-11" }</returnvalue>
+       </para></entry>
+       <entry>No</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_object_agg</primary>
+        </indexterm>
+        <function>json_object_agg</function> ( <parameter>key</parameter>
+         <type>"any"</type>, <parameter>value</parameter>
+         <type>"any"</type>
+         <literal>ORDER BY</literal> <literal>input_sort_columns</literal> )
+        <returnvalue>json</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_object_agg</primary>
+        </indexterm>
+        <function>jsonb_object_agg</function> ( <parameter>key</parameter>
+         <type>"any"</type>, <parameter>value</parameter>
+         <type>"any"</type>
+         <literal>ORDER BY</literal> <literal>input_sort_columns</literal> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Collects all the key/value pairs into a JSON object.  Key arguments
+        are coerced to text; value arguments are converted as per
+        <function>to_json</function> or <function>to_jsonb</function>.
+        Values can be null, but keys cannot.
+       </para></entry>
+       <entry>No</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_object_agg_strict</primary>
+        </indexterm>
+        <function>json_object_agg_strict</function> (
+         <parameter>key</parameter> <type>"any"</type>,
+         <parameter>value</parameter> <type>"any"</type> )
+        <returnvalue>json</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_object_agg_strict</primary>
+        </indexterm>
+        <function>jsonb_object_agg_strict</function> (
+         <parameter>key</parameter> <type>"any"</type>,
+         <parameter>value</parameter> <type>"any"</type> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Collects all the key/value pairs into a JSON object.  Key arguments
+        are coerced to text; value arguments are converted as per
+        <function>to_json</function> or <function>to_jsonb</function>.
+        The <parameter>key</parameter> can not be null. If the
+        <parameter>value</parameter> is null then the entry is skipped,
+       </para></entry>
+       <entry>No</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_object_agg_unique</primary>
+        </indexterm>
+        <function>json_object_agg_unique</function> (
+         <parameter>key</parameter> <type>"any"</type>,
+         <parameter>value</parameter> <type>"any"</type> )
+        <returnvalue>json</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_object_agg_unique</primary>
+        </indexterm>
+        <function>jsonb_object_agg_unique</function> (
+         <parameter>key</parameter> <type>"any"</type>,
+         <parameter>value</parameter> <type>"any"</type> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Collects all the key/value pairs into a JSON object.  Key arguments
+        are coerced to text; value arguments are converted as per
+        <function>to_json</function> or <function>to_jsonb</function>.
+        Values can be null, but keys cannot.
+        If there is a duplicate key an error is thrown.
+       </para></entry>
+       <entry>No</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_object_agg_unique_strict</primary>
+        </indexterm>
+        <function>json_object_agg_unique_strict</function> (
+         <parameter>key</parameter> <type>"any"</type>,
+         <parameter>value</parameter> <type>"any"</type> )
+        <returnvalue>json</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_object_agg_unique_strict</primary>
+        </indexterm>
+        <function>jsonb_object_agg_unique_strict</function> (
+         <parameter>key</parameter> <type>"any"</type>,
+         <parameter>value</parameter> <type>"any"</type> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Collects all the key/value pairs into a JSON object.  Key arguments
+        are coerced to text; value arguments are converted as per
+        <function>to_json</function> or <function>to_jsonb</function>.
+        The <parameter>key</parameter> can not be null. If the
+        <parameter>value</parameter> is null then the entry is skipped.
+        If there is a duplicate key an error is thrown.
+       </para></entry>
+       <entry>No</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>max</primary>
+        </indexterm>
+        <function>max</function> ( <replaceable>see text</replaceable> )
+        <returnvalue><replaceable>same as input type</replaceable></returnvalue>
+       </para>
+       <para>
+        Computes the maximum of the non-null input
+        values.  Available for any numeric, string, date/time, or enum type,
+        as well as <type>bytea</type>, <type>inet</type>, <type>interval</type>,
+        <type>money</type>, <type>oid</type>, <type>pg_lsn</type>,
+        <type>tid</type>, <type>xid8</type>,
+        and also arrays and composite types containing sortable data types.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>min</primary>
+        </indexterm>
+        <function>min</function> ( <replaceable>see text</replaceable> )
+        <returnvalue><replaceable>same as input type</replaceable></returnvalue>
+       </para>
+       <para>
+        Computes the minimum of the non-null input
+        values.  Available for any numeric, string, date/time, or enum type,
+        as well as <type>bytea</type>, <type>inet</type>, <type>interval</type>,
+        <type>money</type>, <type>oid</type>, <type>pg_lsn</type>,
+        <type>tid</type>, <type>xid8</type>,
+        and also arrays and composite types containing sortable data types.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>range_agg</primary>
+        </indexterm>
+        <function>range_agg</function> ( <parameter>value</parameter>
+         <type>anyrange</type> )
+        <returnvalue>anymultirange</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>range_agg</function> ( <parameter>value</parameter>
+         <type>anymultirange</type> )
+        <returnvalue>anymultirange</returnvalue>
+       </para>
+       <para>
+        Computes the union of the non-null input values.
+       </para></entry>
+       <entry>No</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>range_intersect_agg</primary>
+        </indexterm>
+        <function>range_intersect_agg</function> ( <parameter>value</parameter>
+         <type>anyrange</type> )
+        <returnvalue>anyrange</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>range_intersect_agg</function> ( <parameter>value</parameter>
+         <type>anymultirange</type> )
+        <returnvalue>anymultirange</returnvalue>
+       </para>
+       <para>
+        Computes the intersection of the non-null input values.
+       </para></entry>
+       <entry>No</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>string_agg</primary>
+        </indexterm>
+        <function>string_agg</function> ( <parameter>value</parameter>
+         <type>text</type>, <parameter>delimiter</parameter> <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>string_agg</function> ( <parameter>value</parameter>
+         <type>bytea</type>, <parameter>delimiter</parameter> <type>bytea</type>
+         <literal>ORDER BY</literal> <literal>input_sort_columns</literal> )
+        <returnvalue>bytea</returnvalue>
+       </para>
+       <para>
+        Concatenates the non-null input values into a string.  Each value
+        after the first is preceded by the
+        corresponding <parameter>delimiter</parameter> (if it's not null).
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>sum</primary>
+        </indexterm>
+        <function>sum</function> ( <type>smallint</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>sum</function> ( <type>integer</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>sum</function> ( <type>bigint</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>sum</function> ( <type>numeric</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>sum</function> ( <type>real</type> )
+        <returnvalue>real</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>sum</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>sum</function> ( <type>interval</type> )
+        <returnvalue>interval</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>sum</function> ( <type>money</type> )
+        <returnvalue>money</returnvalue>
+       </para>
+       <para>
+        Computes the sum of the non-null input values.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>xmlagg</primary>
+        </indexterm>
+        <function>xmlagg</function> ( <type>xml</type> <literal>ORDER BY</literal> <literal>input_sort_columns</literal> )
+        <returnvalue>xml</returnvalue>
+       </para>
+       <para>
+        Concatenates the non-null XML input values (see
+        <xref linkend="functions-xml-xmlagg"/>).
+       </para></entry>
+       <entry>No</entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <para>
+   It should be noted that except for <function>count</function>,
+   these functions return a null value when no rows are selected.  In
+   particular, <function>sum</function> of no rows returns null, not
+   zero as one might expect, and <function>array_agg</function>
+   returns null rather than an empty array when there are no input
+   rows.  The <function>coalesce</function> function can be used to
+   substitute zero or an empty array for null when necessary.
+  </para>
+
+  <para>
+   The aggregate functions <function>array_agg</function>,
+   <function>json_agg</function>, <function>jsonb_agg</function>,
+   <function>json_agg_strict</function>, <function>jsonb_agg_strict</function>,
+   <function>json_object_agg</function>, <function>jsonb_object_agg</function>,
+   <function>json_object_agg_strict</function>, <function>jsonb_object_agg_strict</function>,
+   <function>json_object_agg_unique</function>, <function>jsonb_object_agg_unique</function>,
+   <function>json_object_agg_unique_strict</function>,
+   <function>jsonb_object_agg_unique_strict</function>,
+   <function>string_agg</function>,
+   and <function>xmlagg</function>, as well as similar user-defined
+   aggregate functions, produce meaningfully different result values
+   depending on the order of the input values.  This ordering is
+   unspecified by default, but can be controlled by writing an
+   <literal>ORDER BY</literal> clause within the aggregate call, as shown in
+   <xref linkend="syntax-aggregates"/>.
+   Alternatively, supplying the input values from a sorted subquery
+   will usually work.  For example:
+
+<screen><![CDATA[
+SELECT xmlagg(x) FROM (SELECT x FROM test ORDER BY y DESC) AS tab;
+]]></screen>
+
+   Beware that this approach can fail if the outer query level contains
+   additional processing, such as a join, because that might cause the
+   subquery's output to be reordered before the aggregate is computed.
+  </para>
+
+  <note>
+    <indexterm>
+      <primary>ANY</primary>
+    </indexterm>
+    <indexterm>
+      <primary>SOME</primary>
+    </indexterm>
+    <para>
+      The boolean aggregates <function>bool_and</function> and
+      <function>bool_or</function> correspond to the standard SQL aggregates
+      <function>every</function> and <function>any</function> or
+      <function>some</function>.
+      <productname>PostgreSQL</productname>
+      supports <function>every</function>, but not <function>any</function>
+      or <function>some</function>, because there is an ambiguity built into
+      the standard syntax:
+<programlisting>
+SELECT b1 = ANY((SELECT b2 FROM t2 ...)) FROM t1 ...;
+</programlisting>
+      Here <function>ANY</function> can be considered either as introducing
+      a subquery, or as being an aggregate function, if the subquery
+      returns one row with a Boolean value.
+      Thus the standard name cannot be given to these aggregates.
+    </para>
+  </note>
+
+  <note>
+   <para>
+    Users accustomed to working with other SQL database management
+    systems might be disappointed by the performance of the
+    <function>count</function> aggregate when it is applied to the
+    entire table. A query like:
+<programlisting>
+SELECT count(*) FROM sometable;
+</programlisting>
+    will require effort proportional to the size of the table:
+    <productname>PostgreSQL</productname> will need to scan either the
+    entire table or the entirety of an index that includes all rows in
+    the table.
+   </para>
+  </note>
+
+  <para>
+   <xref linkend="functions-aggregate-statistics-table"/> shows
+   aggregate functions typically used in statistical analysis.
+   (These are separated out merely to avoid cluttering the listing
+   of more-commonly-used aggregates.)  Functions shown as
+   accepting <replaceable>numeric_type</replaceable> are available for all
+   the types <type>smallint</type>, <type>integer</type>,
+   <type>bigint</type>, <type>numeric</type>, <type>real</type>,
+   and <type>double precision</type>.
+   Where the description mentions
+   <parameter>N</parameter>, it means the
+   number of input rows for which all the input expressions are non-null.
+   In all cases, null is returned if the computation is meaningless,
+   for example when <parameter>N</parameter> is zero.
+  </para>
+
+  <indexterm>
+   <primary>statistics</primary>
+  </indexterm>
+  <indexterm>
+   <primary>linear regression</primary>
+  </indexterm>
+
+   <table id="functions-aggregate-statistics-table">
+    <title>Aggregate Functions for Statistics</title>
+    <tgroup cols="2">
+     <colspec colname="col1" colwidth="10*"/>
+     <colspec colname="col2" colwidth="1*"/>
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+       <entry>Partial Mode</entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>correlation</primary>
+        </indexterm>
+        <indexterm>
+         <primary>corr</primary>
+        </indexterm>
+        <function>corr</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes the correlation coefficient.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>covariance</primary>
+         <secondary>population</secondary>
+        </indexterm>
+        <indexterm>
+         <primary>covar_pop</primary>
+        </indexterm>
+        <function>covar_pop</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes the population covariance.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>covariance</primary>
+         <secondary>sample</secondary>
+        </indexterm>
+        <indexterm>
+         <primary>covar_samp</primary>
+        </indexterm>
+        <function>covar_samp</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes the sample covariance.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regr_avgx</primary>
+        </indexterm>
+        <function>regr_avgx</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes the average of the independent variable,
+        <literal>sum(<parameter>X</parameter>)/<parameter>N</parameter></literal>.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regr_avgy</primary>
+        </indexterm>
+        <function>regr_avgy</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes the average of the dependent variable,
+        <literal>sum(<parameter>Y</parameter>)/<parameter>N</parameter></literal>.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regr_count</primary>
+        </indexterm>
+        <function>regr_count</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Computes the number of rows in which both inputs are non-null.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regression intercept</primary>
+        </indexterm>
+        <indexterm>
+         <primary>regr_intercept</primary>
+        </indexterm>
+        <function>regr_intercept</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes the y-intercept of the least-squares-fit linear equation
+        determined by the
+        (<parameter>X</parameter>, <parameter>Y</parameter>) pairs.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regr_r2</primary>
+        </indexterm>
+        <function>regr_r2</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes the square of the correlation coefficient.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regression slope</primary>
+        </indexterm>
+        <indexterm>
+         <primary>regr_slope</primary>
+        </indexterm>
+        <function>regr_slope</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes the slope of the least-squares-fit linear equation determined
+        by the (<parameter>X</parameter>, <parameter>Y</parameter>)
+        pairs.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regr_sxx</primary>
+        </indexterm>
+        <function>regr_sxx</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes the <quote>sum of squares</quote> of the independent
+        variable,
+        <literal>sum(<parameter>X</parameter>^2) - sum(<parameter>X</parameter>)^2/<parameter>N</parameter></literal>.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regr_sxy</primary>
+        </indexterm>
+        <function>regr_sxy</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes the <quote>sum of products</quote> of independent times
+        dependent variables,
+        <literal>sum(<parameter>X</parameter>*<parameter>Y</parameter>) - sum(<parameter>X</parameter>) * sum(<parameter>Y</parameter>)/<parameter>N</parameter></literal>.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regr_syy</primary>
+        </indexterm>
+        <function>regr_syy</function> ( <parameter>Y</parameter> <type>double precision</type>, <parameter>X</parameter> <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes the <quote>sum of squares</quote> of the dependent
+        variable,
+        <literal>sum(<parameter>Y</parameter>^2) - sum(<parameter>Y</parameter>)^2/<parameter>N</parameter></literal>.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>standard deviation</primary>
+        </indexterm>
+        <indexterm>
+         <primary>stddev</primary>
+        </indexterm>
+        <function>stddev</function> ( <replaceable>numeric_type</replaceable> )
+        <returnvalue></returnvalue> <type>double precision</type>
+        for <type>real</type> or <type>double precision</type>,
+        otherwise <type>numeric</type>
+       </para>
+       <para>
+        This is a historical alias for <function>stddev_samp</function>.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>standard deviation</primary>
+         <secondary>population</secondary>
+        </indexterm>
+        <indexterm>
+         <primary>stddev_pop</primary>
+        </indexterm>
+        <function>stddev_pop</function> ( <replaceable>numeric_type</replaceable> )
+        <returnvalue></returnvalue> <type>double precision</type>
+        for <type>real</type> or <type>double precision</type>,
+        otherwise <type>numeric</type>
+       </para>
+       <para>
+        Computes the population standard deviation of the input values.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>standard deviation</primary>
+         <secondary>sample</secondary>
+        </indexterm>
+        <indexterm>
+         <primary>stddev_samp</primary>
+        </indexterm>
+        <function>stddev_samp</function> ( <replaceable>numeric_type</replaceable> )
+        <returnvalue></returnvalue> <type>double precision</type>
+        for <type>real</type> or <type>double precision</type>,
+        otherwise <type>numeric</type>
+       </para>
+       <para>
+        Computes the sample standard deviation of the input values.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>variance</primary>
+        </indexterm>
+        <function>variance</function> ( <replaceable>numeric_type</replaceable> )
+        <returnvalue></returnvalue> <type>double precision</type>
+        for <type>real</type> or <type>double precision</type>,
+        otherwise <type>numeric</type>
+       </para>
+       <para>
+        This is a historical alias for <function>var_samp</function>.
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>variance</primary>
+         <secondary>population</secondary>
+        </indexterm>
+        <indexterm>
+         <primary>var_pop</primary>
+        </indexterm>
+        <function>var_pop</function> ( <replaceable>numeric_type</replaceable> )
+        <returnvalue></returnvalue> <type>double precision</type>
+        for <type>real</type> or <type>double precision</type>,
+        otherwise <type>numeric</type>
+       </para>
+       <para>
+        Computes the population variance of the input values (square of the
+        population standard deviation).
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>variance</primary>
+         <secondary>sample</secondary>
+        </indexterm>
+        <indexterm>
+         <primary>var_samp</primary>
+        </indexterm>
+        <function>var_samp</function> ( <replaceable>numeric_type</replaceable> )
+        <returnvalue></returnvalue> <type>double precision</type>
+        for <type>real</type> or <type>double precision</type>,
+        otherwise <type>numeric</type>
+       </para>
+       <para>
+        Computes the sample variance of the input values (square of the sample
+        standard deviation).
+       </para></entry>
+       <entry>Yes</entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <para>
+   <xref linkend="functions-orderedset-table"/> shows some
+   aggregate functions that use the <firstterm>ordered-set aggregate</firstterm>
+   syntax.  These functions are sometimes referred to as <quote>inverse
+   distribution</quote> functions.  Their aggregated input is introduced by
+   <literal>ORDER BY</literal>, and they may also take a <firstterm>direct
+   argument</firstterm> that is not aggregated, but is computed only once.
+   All these functions ignore null values in their aggregated input.
+   For those that take a <parameter>fraction</parameter> parameter, the
+   fraction value must be between 0 and 1; an error is thrown if not.
+   However, a null <parameter>fraction</parameter> value simply produces a
+   null result.
+  </para>
+
+  <indexterm>
+   <primary>ordered-set aggregate</primary>
+   <secondary>built-in</secondary>
+  </indexterm>
+  <indexterm>
+   <primary>inverse distribution</primary>
+  </indexterm>
+
+   <table id="functions-orderedset-table">
+    <title>Ordered-Set Aggregate Functions</title>
+    <tgroup cols="2">
+     <colspec colname="col1" colwidth="10*"/>
+     <colspec colname="col2" colwidth="1*"/>
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+       <entry>Partial Mode</entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>mode</primary>
+         <secondary>statistical</secondary>
+        </indexterm>
+        <function>mode</function> () <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Computes the <firstterm>mode</firstterm>, the most frequent
+        value of the aggregated argument (arbitrarily choosing the first one
+        if there are multiple equally-frequent values).  The aggregated
+        argument must be of a sortable type.
+       </para></entry>
+       <entry>No</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>percentile</primary>
+         <secondary>continuous</secondary>
+        </indexterm>
+        <function>percentile_cont</function> ( <parameter>fraction</parameter> <type>double precision</type> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>percentile_cont</function> ( <parameter>fraction</parameter> <type>double precision</type> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <type>interval</type> )
+        <returnvalue>interval</returnvalue>
+       </para>
+       <para>
+        Computes the <firstterm>continuous percentile</firstterm>, a value
+        corresponding to the specified <parameter>fraction</parameter>
+        within the ordered set of aggregated argument values.  This will
+        interpolate between adjacent input items if needed.
+       </para></entry>
+       <entry>No</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>percentile_cont</function> ( <parameter>fractions</parameter> <type>double precision[]</type> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <type>double precision</type> )
+        <returnvalue>double precision[]</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>percentile_cont</function> ( <parameter>fractions</parameter> <type>double precision[]</type> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <type>interval</type> )
+        <returnvalue>interval[]</returnvalue>
+       </para>
+       <para>
+        Computes multiple continuous percentiles.  The result is an array of
+        the same dimensions as the <parameter>fractions</parameter>
+        parameter, with each non-null element replaced by the (possibly
+        interpolated) value corresponding to that percentile.
+       </para></entry>
+       <entry>No</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>percentile</primary>
+         <secondary>discrete</secondary>
+        </indexterm>
+        <function>percentile_disc</function> ( <parameter>fraction</parameter> <type>double precision</type> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Computes the <firstterm>discrete percentile</firstterm>, the first
+        value within the ordered set of aggregated argument values whose
+        position in the ordering equals or exceeds the
+        specified <parameter>fraction</parameter>.  The aggregated
+        argument must be of a sortable type.
+       </para></entry>
+       <entry>No</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>percentile_disc</function> ( <parameter>fractions</parameter> <type>double precision[]</type> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <type>anyelement</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Computes multiple discrete percentiles.  The result is an array of the
+        same dimensions as the <parameter>fractions</parameter> parameter,
+        with each non-null element replaced by the input value corresponding
+        to that percentile.
+        The aggregated argument must be of a sortable type.
+       </para></entry>
+       <entry>No</entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <indexterm>
+   <primary>hypothetical-set aggregate</primary>
+   <secondary>built-in</secondary>
+  </indexterm>
+
+  <para>
+   Each of the <quote>hypothetical-set</quote> aggregates listed in
+   <xref linkend="functions-hypothetical-table"/> is associated with a
+   window function of the same name defined in
+   <xref linkend="functions-window"/>.  In each case, the aggregate's result
+   is the value that the associated window function would have
+   returned for the <quote>hypothetical</quote> row constructed from
+   <replaceable>args</replaceable>, if such a row had been added to the sorted
+   group of rows represented by the <replaceable>sorted_args</replaceable>.
+   For each of these functions, the list of direct arguments
+   given in <replaceable>args</replaceable> must match the number and types of
+   the aggregated arguments given in <replaceable>sorted_args</replaceable>.
+   Unlike most built-in aggregates, these aggregates are not strict, that is
+   they do not drop input rows containing nulls.  Null values sort according
+   to the rule specified in the <literal>ORDER BY</literal> clause.
+  </para>
+
+   <table id="functions-hypothetical-table">
+    <title>Hypothetical-Set Aggregate Functions</title>
+    <tgroup cols="2">
+     <colspec colname="col1" colwidth="10*"/>
+     <colspec colname="col2" colwidth="1*"/>
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+       <entry>Partial Mode</entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rank</primary>
+         <secondary>hypothetical</secondary>
+        </indexterm>
+        <function>rank</function> ( <replaceable>args</replaceable> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <replaceable>sorted_args</replaceable> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Computes the rank of the hypothetical row, with gaps; that is, the row
+        number of the first row in its peer group.
+       </para></entry>
+       <entry>No</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>dense_rank</primary>
+         <secondary>hypothetical</secondary>
+        </indexterm>
+        <function>dense_rank</function> ( <replaceable>args</replaceable> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <replaceable>sorted_args</replaceable> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Computes the rank of the hypothetical row, without gaps; this function
+        effectively counts peer groups.
+       </para></entry>
+       <entry>No</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>percent_rank</primary>
+         <secondary>hypothetical</secondary>
+        </indexterm>
+        <function>percent_rank</function> ( <replaceable>args</replaceable> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <replaceable>sorted_args</replaceable> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes the relative rank of the hypothetical row, that is
+        (<function>rank</function> - 1) / (total rows - 1).
+        The value thus ranges from 0 to 1 inclusive.
+       </para></entry>
+       <entry>No</entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>cume_dist</primary>
+         <secondary>hypothetical</secondary>
+        </indexterm>
+        <function>cume_dist</function> ( <replaceable>args</replaceable> ) <literal>WITHIN GROUP</literal> ( <literal>ORDER BY</literal> <replaceable>sorted_args</replaceable> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes the cumulative distribution, that is (number of rows
+        preceding or peers with hypothetical row) / (total rows).  The value
+        thus ranges from 1/<parameter>N</parameter> to 1.
+       </para></entry>
+       <entry>No</entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <table id="functions-grouping-table">
+   <title>Grouping Operations</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>GROUPING</primary>
+        </indexterm>
+        <function>GROUPING</function> ( <replaceable>group_by_expression(s)</replaceable> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns a bit mask indicating which <literal>GROUP BY</literal>
+        expressions are not included in the current grouping set.
+        Bits are assigned with the rightmost argument corresponding to the
+        least-significant bit; each bit is 0 if the corresponding expression
+        is included in the grouping criteria of the grouping set generating
+        the current result row, and 1 if it is not included.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    The grouping operations shown in
+    <xref linkend="functions-grouping-table"/> are used in conjunction with
+    grouping sets (see <xref linkend="queries-grouping-sets"/>) to distinguish
+    result rows.  The arguments to the <literal>GROUPING</literal> function
+    are not actually evaluated, but they must exactly match expressions given
+    in the <literal>GROUP BY</literal> clause of the associated query level.
+    For example:
+<screen>
+<prompt>=&gt;</prompt> <userinput>SELECT * FROM items_sold;</userinput>
+ make  | model | sales
+-------+-------+-------
+ Foo   | GT    |  10
+ Foo   | Tour  |  20
+ Bar   | City  |  15
+ Bar   | Sport |  5
+(4 rows)
+
+<prompt>=&gt;</prompt> <userinput>SELECT make, model, GROUPING(make,model), sum(sales) FROM items_sold GROUP BY ROLLUP(make,model);</userinput>
+ make  | model | grouping | sum
+-------+-------+----------+-----
+ Foo   | GT    |        0 | 10
+ Foo   | Tour  |        0 | 20
+ Bar   | City  |        0 | 15
+ Bar   | Sport |        0 | 5
+ Foo   |       |        1 | 30
+ Bar   |       |        1 | 20
+       |       |        3 | 50
+(7 rows)
+</screen>
+    Here, the <literal>grouping</literal> value <literal>0</literal> in the
+    first four rows shows that those have been grouped normally, over both the
+    grouping columns.  The value <literal>1</literal> indicates
+    that <literal>model</literal> was not grouped by in the next-to-last two
+    rows, and the value <literal>3</literal> indicates that
+    neither <literal>make</literal> nor <literal>model</literal> was grouped
+    by in the last row (which therefore is an aggregate over all the input
+    rows).
+   </para>
+
+ </sect1>
diff --git a/doc/src/sgml/func/func-array.sgml b/doc/src/sgml/func/func-array.sgml
new file mode 100644
index 0000000000000..97e4865a5f7d2
--- /dev/null
+++ b/doc/src/sgml/func/func-array.sgml
@@ -0,0 +1,646 @@
+ <sect1 id="functions-array">
+  <title>Array Functions and Operators</title>
+
+  <para>
+   <xref linkend="array-operators-table"/> shows the specialized operators
+   available for array types.
+   In addition to those, the usual comparison operators shown in <xref
+   linkend="functions-comparison-op-table"/> are available for
+   arrays.  The comparison operators compare the array contents
+   element-by-element, using the default B-tree comparison function for
+   the element data type, and sort based on the first difference.
+   In multidimensional arrays the elements are visited in row-major order
+   (last subscript varies most rapidly).
+   If the contents of two arrays are equal but the dimensionality is
+   different, the first difference in the dimensionality information
+   determines the sort order.
+  </para>
+
+   <table id="array-operators-table">
+    <title>Array Operators</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Operator
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyarray</type> <literal>@&gt;</literal> <type>anyarray</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the first array contain the second, that is, does each element
+        appearing in the second array equal some element of the first array?
+        (Duplicates are not treated specially,
+        thus <literal>ARRAY[1]</literal> and <literal>ARRAY[1,1]</literal> are
+        each considered to contain the other.)
+       </para>
+       <para>
+        <literal>ARRAY[1,4,3] @&gt; ARRAY[3,1,3]</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyarray</type> <literal>&lt;@</literal> <type>anyarray</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the first array contained by the second?
+       </para>
+       <para>
+        <literal>ARRAY[2,2,7] &lt;@ ARRAY[1,7,4,2,6]</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyarray</type> <literal>&amp;&amp;</literal> <type>anyarray</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Do the arrays overlap, that is, have any elements in common?
+       </para>
+       <para>
+        <literal>ARRAY[1,4,3] &amp;&amp; ARRAY[2,1]</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anycompatiblearray</type> <literal>||</literal> <type>anycompatiblearray</type>
+        <returnvalue>anycompatiblearray</returnvalue>
+       </para>
+       <para>
+        Concatenates the two arrays.  Concatenating a null or empty array is a
+        no-op; otherwise the arrays must have the same number of dimensions
+        (as illustrated by the first example) or differ in number of
+        dimensions by one (as illustrated by the second).
+        If the arrays are not of identical element types, they will be coerced
+        to a common type (see <xref linkend="typeconv-union-case"/>).
+       </para>
+       <para>
+        <literal>ARRAY[1,2,3] || ARRAY[4,5,6,7]</literal>
+        <returnvalue>{1,2,3,4,5,6,7}</returnvalue>
+       </para>
+       <para>
+        <literal>ARRAY[1,2,3] || ARRAY[[4,5,6],[7,8,9.9]]</literal>
+        <returnvalue>{{1,2,3},{4,5,6},{7,8,9.9}}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anycompatible</type> <literal>||</literal> <type>anycompatiblearray</type>
+        <returnvalue>anycompatiblearray</returnvalue>
+       </para>
+       <para>
+        Concatenates an element onto the front of an array (which must be
+        empty or one-dimensional).
+       </para>
+       <para>
+        <literal>3 || ARRAY[4,5,6]</literal>
+        <returnvalue>{3,4,5,6}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anycompatiblearray</type> <literal>||</literal> <type>anycompatible</type>
+        <returnvalue>anycompatiblearray</returnvalue>
+       </para>
+       <para>
+        Concatenates an element onto the end of an array (which must be
+        empty or one-dimensional).
+       </para>
+       <para>
+        <literal>ARRAY[4,5,6] || 7</literal>
+        <returnvalue>{4,5,6,7}</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <para>
+   See <xref linkend="arrays"/> for more details about array operator
+   behavior.  See <xref linkend="indexes-types"/> for more details about
+   which operators support indexed operations.
+  </para>
+
+  <para>
+   <xref linkend="array-functions-table"/> shows the functions
+   available for use with array types. See <xref linkend="arrays"/>
+   for more information  and examples of the use of these functions.
+  </para>
+
+   <table id="array-functions-table">
+    <title>Array Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_append</primary>
+        </indexterm>
+        <function>array_append</function> ( <type>anycompatiblearray</type>, <type>anycompatible</type> )
+        <returnvalue>anycompatiblearray</returnvalue>
+       </para>
+       <para>
+        Appends an element to the end of an array (same as
+        the <type>anycompatiblearray</type> <literal>||</literal> <type>anycompatible</type>
+        operator).
+       </para>
+       <para>
+        <literal>array_append(ARRAY[1,2], 3)</literal>
+        <returnvalue>{1,2,3}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_cat</primary>
+        </indexterm>
+        <function>array_cat</function> ( <type>anycompatiblearray</type>, <type>anycompatiblearray</type> )
+        <returnvalue>anycompatiblearray</returnvalue>
+       </para>
+       <para>
+        Concatenates two arrays (same as
+        the <type>anycompatiblearray</type> <literal>||</literal> <type>anycompatiblearray</type>
+        operator).
+       </para>
+       <para>
+        <literal>array_cat(ARRAY[1,2,3], ARRAY[4,5])</literal>
+        <returnvalue>{1,2,3,4,5}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_dims</primary>
+        </indexterm>
+        <function>array_dims</function> ( <type>anyarray</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns a text representation of the array's dimensions.
+       </para>
+       <para>
+        <literal>array_dims(ARRAY[[1,2,3], [4,5,6]])</literal>
+        <returnvalue>[1:2][1:3]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_fill</primary>
+        </indexterm>
+        <function>array_fill</function> ( <type>anyelement</type>, <type>integer[]</type>
+          <optional>, <type>integer[]</type> </optional> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Returns an array filled with copies of the given value, having
+        dimensions of the lengths specified by the second argument.
+        The optional third argument supplies lower-bound values for each
+        dimension (which default to all <literal>1</literal>).
+       </para>
+       <para>
+        <literal>array_fill(11, ARRAY[2,3])</literal>
+        <returnvalue>{{11,11,11},{11,11,11}}</returnvalue>
+       </para>
+       <para>
+        <literal>array_fill(7, ARRAY[3], ARRAY[2])</literal>
+        <returnvalue>[2:4]={7,7,7}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_length</primary>
+        </indexterm>
+        <function>array_length</function> ( <type>anyarray</type>, <type>integer</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the length of the requested array dimension.
+        (Produces NULL instead of 0 for empty or missing array dimensions.)
+       </para>
+       <para>
+        <literal>array_length(array[1,2,3], 1)</literal>
+        <returnvalue>3</returnvalue>
+       </para>
+       <para>
+        <literal>array_length(array[]::int[], 1)</literal>
+        <returnvalue>NULL</returnvalue>
+       </para>
+       <para>
+        <literal>array_length(array['text'], 2)</literal>
+        <returnvalue>NULL</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_lower</primary>
+        </indexterm>
+        <function>array_lower</function> ( <type>anyarray</type>, <type>integer</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the lower bound of the requested array dimension.
+       </para>
+       <para>
+        <literal>array_lower('[0:2]={1,2,3}'::integer[], 1)</literal>
+        <returnvalue>0</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_ndims</primary>
+        </indexterm>
+        <function>array_ndims</function> ( <type>anyarray</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the number of dimensions of the array.
+       </para>
+       <para>
+        <literal>array_ndims(ARRAY[[1,2,3], [4,5,6]])</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_position</primary>
+        </indexterm>
+        <function>array_position</function> ( <type>anycompatiblearray</type>, <type>anycompatible</type> <optional>, <type>integer</type> </optional> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the subscript of the first occurrence of the second argument
+        in the array, or <literal>NULL</literal> if it's not present.
+        If the third argument is given, the search begins at that subscript.
+        The array must be one-dimensional.
+        Comparisons are done using <literal>IS NOT DISTINCT FROM</literal>
+        semantics, so it is possible to search for <literal>NULL</literal>.
+       </para>
+       <para>
+        <literal>array_position(ARRAY['sun', 'mon', 'tue', 'wed', 'thu', 'fri', 'sat'], 'mon')</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_positions</primary>
+        </indexterm>
+        <function>array_positions</function> ( <type>anycompatiblearray</type>, <type>anycompatible</type> )
+        <returnvalue>integer[]</returnvalue>
+       </para>
+       <para>
+        Returns an array of the subscripts of all occurrences of the second
+        argument in the array given as first argument.
+        The array must be one-dimensional.
+        Comparisons are done using <literal>IS NOT DISTINCT FROM</literal>
+        semantics, so it is possible to search for <literal>NULL</literal>.
+        <literal>NULL</literal> is returned only if the array
+        is <literal>NULL</literal>; if the value is not found in the array, an
+        empty array is returned.
+       </para>
+       <para>
+        <literal>array_positions(ARRAY['A','A','B','A'], 'A')</literal>
+        <returnvalue>{1,2,4}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_prepend</primary>
+        </indexterm>
+        <function>array_prepend</function> ( <type>anycompatible</type>, <type>anycompatiblearray</type> )
+        <returnvalue>anycompatiblearray</returnvalue>
+       </para>
+       <para>
+        Prepends an element to the beginning of an array (same as
+        the <type>anycompatible</type> <literal>||</literal> <type>anycompatiblearray</type>
+        operator).
+       </para>
+       <para>
+        <literal>array_prepend(1, ARRAY[2,3])</literal>
+        <returnvalue>{1,2,3}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_remove</primary>
+        </indexterm>
+        <function>array_remove</function> ( <type>anycompatiblearray</type>, <type>anycompatible</type> )
+        <returnvalue>anycompatiblearray</returnvalue>
+       </para>
+       <para>
+        Removes all elements equal to the given value from the array.
+        The array must be one-dimensional.
+        Comparisons are done using <literal>IS NOT DISTINCT FROM</literal>
+        semantics, so it is possible to remove <literal>NULL</literal>s.
+       </para>
+       <para>
+        <literal>array_remove(ARRAY[1,2,3,2], 2)</literal>
+        <returnvalue>{1,3}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_replace</primary>
+        </indexterm>
+        <function>array_replace</function> ( <type>anycompatiblearray</type>, <type>anycompatible</type>, <type>anycompatible</type> )
+        <returnvalue>anycompatiblearray</returnvalue>
+       </para>
+       <para>
+        Replaces each array element equal to the second argument with the
+        third argument.
+       </para>
+       <para>
+        <literal>array_replace(ARRAY[1,2,5,4], 5, 3)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_reverse</primary>
+        </indexterm>
+        <function>array_reverse</function> ( <type>anyarray</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Reverses the first dimension of the array.
+       </para>
+       <para>
+        <literal>array_reverse(ARRAY[[1,2],[3,4],[5,6]])</literal>
+        <returnvalue>{{5,6},{3,4},{1,2}}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_sample</primary>
+        </indexterm>
+        <function>array_sample</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Returns an array of <parameter>n</parameter> items randomly selected
+        from <parameter>array</parameter>.  <parameter>n</parameter> may not
+        exceed the length of <parameter>array</parameter>'s first dimension.
+        If <parameter>array</parameter> is multi-dimensional,
+        an <quote>item</quote> is a slice having a given first subscript.
+       </para>
+       <para>
+        <literal>array_sample(ARRAY[1,2,3,4,5,6], 3)</literal>
+        <returnvalue>{2,6,1}</returnvalue>
+       </para>
+       <para>
+        <literal>array_sample(ARRAY[[1,2],[3,4],[5,6]], 2)</literal>
+        <returnvalue>{{5,6},{1,2}}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_shuffle</primary>
+        </indexterm>
+        <function>array_shuffle</function> ( <type>anyarray</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Randomly shuffles the first dimension of the array.
+       </para>
+       <para>
+        <literal>array_shuffle(ARRAY[[1,2],[3,4],[5,6]])</literal>
+        <returnvalue>{{5,6},{1,2},{3,4}}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_sort</primary>
+        </indexterm>
+        <function>array_sort</function> (
+          <parameter>array</parameter> <type>anyarray</type>
+          <optional>, <parameter>descending</parameter> <type>boolean</type>
+          <optional>, <parameter>nulls_first</parameter> <type>boolean</type>
+          </optional></optional> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Sorts the first dimension of the array.
+        The sort order is determined by the default sort ordering of the
+        array's element type; however, if the element type is collatable,
+        the collation to use can be specified by adding
+        a <literal>COLLATE</literal> clause to
+        the <parameter>array</parameter> argument.
+       </para>
+       <para>
+        If <parameter>descending</parameter> is true then sort in
+        descending order, otherwise ascending order.  If omitted, the
+        default is ascending order.
+        If <parameter>nulls_first</parameter> is true then nulls appear
+        before non-null values, otherwise nulls appear after non-null
+        values.
+        If omitted, <parameter>nulls_first</parameter> is taken to have
+        the same value as <parameter>descending</parameter>.
+       </para>
+       <para>
+        <literal>array_sort(ARRAY[[2,4],[2,1],[6,5]])</literal>
+        <returnvalue>{{2,1},{2,4},{6,5}}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm id="function-array-to-string">
+         <primary>array_to_string</primary>
+        </indexterm>
+        <function>array_to_string</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>delimiter</parameter> <type>text</type> <optional>, <parameter>null_string</parameter> <type>text</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts each array element to its text representation, and
+        concatenates those separated by
+        the <parameter>delimiter</parameter> string.
+        If <parameter>null_string</parameter> is given and is
+        not <literal>NULL</literal>, then <literal>NULL</literal> array
+        entries are represented by that string; otherwise, they are omitted.
+        See also <link linkend="function-string-to-array"><function>string_to_array</function></link>.
+       </para>
+       <para>
+        <literal>array_to_string(ARRAY[1, 2, 3, NULL, 5], ',', '*')</literal>
+        <returnvalue>1,2,3,*,5</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_upper</primary>
+        </indexterm>
+        <function>array_upper</function> ( <type>anyarray</type>, <type>integer</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the upper bound of the requested array dimension.
+       </para>
+       <para>
+        <literal>array_upper(ARRAY[1,8,3,7], 1)</literal>
+        <returnvalue>4</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>cardinality</primary>
+        </indexterm>
+        <function>cardinality</function> ( <type>anyarray</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the total number of elements in the array, or 0 if the array
+        is empty.
+       </para>
+       <para>
+        <literal>cardinality(ARRAY[[1,2],[3,4]])</literal>
+        <returnvalue>4</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_array</primary>
+        </indexterm>
+        <function>trim_array</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Trims an array by removing the last <parameter>n</parameter> elements.
+        If the array is multidimensional, only the first dimension is trimmed.
+       </para>
+       <para>
+        <literal>trim_array(ARRAY[1,2,3,4,5,6], 2)</literal>
+        <returnvalue>{1,2,3,4}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>unnest</primary>
+        </indexterm>
+        <function>unnest</function> ( <type>anyarray</type> )
+        <returnvalue>setof anyelement</returnvalue>
+       </para>
+       <para>
+        Expands an array into a set of rows.
+        The array's elements are read out in storage order.
+       </para>
+       <para>
+        <literal>unnest(ARRAY[1,2])</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ 1
+ 2
+</programlisting>
+       </para>
+       <para>
+        <literal>unnest(ARRAY[['foo','bar'],['baz','quux']])</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ foo
+ bar
+ baz
+ quux
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>unnest</function> ( <type>anyarray</type>, <type>anyarray</type> <optional>, ... </optional> )
+        <returnvalue>setof anyelement, anyelement [, ... ]</returnvalue>
+       </para>
+       <para>
+        Expands multiple arrays (possibly of different data types) into a set of
+        rows.  If the arrays are not all the same length then the shorter ones
+        are padded with <literal>NULL</literal>s.  This form is only allowed
+        in a query's FROM clause; see <xref linkend="queries-tablefunctions"/>.
+       </para>
+       <para>
+        <literal>select * from unnest(ARRAY[1,2], ARRAY['foo','bar','baz']) as x(a,b)</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ a |  b
+---+-----
+ 1 | foo
+ 2 | bar
+   | baz
+</programlisting>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    See also <xref linkend="functions-aggregate"/> about the aggregate
+    function <function>array_agg</function> for use with arrays.
+   </para>
+  </sect1>
diff --git a/doc/src/sgml/func/func-binarystring.sgml b/doc/src/sgml/func/func-binarystring.sgml
new file mode 100644
index 0000000000000..78814ee0685eb
--- /dev/null
+++ b/doc/src/sgml/func/func-binarystring.sgml
@@ -0,0 +1,854 @@
+  <sect1 id="functions-binarystring">
+   <title>Binary String Functions and Operators</title>
+
+   <indexterm zone="functions-binarystring">
+    <primary>binary data</primary>
+    <secondary>functions</secondary>
+   </indexterm>
+
+   <para>
+    This section describes functions and operators for examining and
+    manipulating binary strings, that is values of type <type>bytea</type>.
+    Many of these are equivalent, in purpose and syntax, to the
+    text-string functions described in the previous section.
+   </para>
+
+   <para>
+    <acronym>SQL</acronym> defines some string functions that use
+    key words, rather than commas, to separate
+    arguments.  Details are in
+    <xref linkend="functions-binarystring-sql"/>.
+    <productname>PostgreSQL</productname> also provides versions of these functions
+    that use the regular function invocation syntax
+    (see <xref linkend="functions-binarystring-other"/>).
+   </para>
+
+   <table id="functions-binarystring-sql">
+    <title><acronym>SQL</acronym> Binary String Functions and Operators</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function/Operator
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>binary string</primary>
+         <secondary>concatenation</secondary>
+        </indexterm>
+        <type>bytea</type> <literal>||</literal> <type>bytea</type>
+        <returnvalue>bytea</returnvalue>
+       </para>
+       <para>
+        Concatenates the two binary strings.
+       </para>
+       <para>
+        <literal>'\x123456'::bytea || '\x789a00bcde'::bytea</literal>
+        <returnvalue>\x123456789a00bcde</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>bit_length</primary>
+        </indexterm>
+        <function>bit_length</function> ( <type>bytea</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns number of bits in the binary string (8
+        times the <function>octet_length</function>).
+       </para>
+       <para>
+        <literal>bit_length('\x123456'::bytea)</literal>
+        <returnvalue>24</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>btrim</primary>
+        </indexterm>
+        <function>btrim</function> ( <parameter>bytes</parameter> <type>bytea</type>,
+        <parameter>bytesremoved</parameter> <type>bytea</type> )
+        <returnvalue>bytea</returnvalue>
+       </para>
+       <para>
+        Removes the longest string containing only bytes appearing in
+        <parameter>bytesremoved</parameter> from the start and end of
+        <parameter>bytes</parameter>.
+       </para>
+       <para>
+        <literal>btrim('\x1234567890'::bytea, '\x9012'::bytea)</literal>
+        <returnvalue>\x345678</returnvalue>
+       </para></entry>
+      </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>ltrim</primary>
+         </indexterm>
+         <function>ltrim</function> ( <parameter>bytes</parameter> <type>bytea</type>,
+         <parameter>bytesremoved</parameter> <type>bytea</type> )
+         <returnvalue>bytea</returnvalue>
+        </para>
+        <para>
+         Removes the longest string containing only bytes appearing in
+         <parameter>bytesremoved</parameter> from the start of
+         <parameter>bytes</parameter>.
+        </para>
+        <para>
+         <literal>ltrim('\x1234567890'::bytea, '\x9012'::bytea)</literal>
+         <returnvalue>\x34567890</returnvalue>
+        </para></entry>
+       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>octet_length</primary>
+        </indexterm>
+        <function>octet_length</function> ( <type>bytea</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns number of bytes in the binary string.
+       </para>
+       <para>
+        <literal>octet_length('\x123456'::bytea)</literal>
+        <returnvalue>3</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>overlay</primary>
+        </indexterm>
+        <function>overlay</function> ( <parameter>bytes</parameter> <type>bytea</type> <literal>PLACING</literal> <parameter>newsubstring</parameter> <type>bytea</type> <literal>FROM</literal> <parameter>start</parameter> <type>integer</type> <optional> <literal>FOR</literal> <parameter>count</parameter> <type>integer</type> </optional> )
+        <returnvalue>bytea</returnvalue>
+       </para>
+       <para>
+        Replaces the substring of <parameter>bytes</parameter> that starts at
+        the <parameter>start</parameter>'th byte and extends
+        for <parameter>count</parameter> bytes
+        with <parameter>newsubstring</parameter>.
+        If <parameter>count</parameter> is omitted, it defaults to the length
+        of <parameter>newsubstring</parameter>.
+       </para>
+       <para>
+        <literal>overlay('\x1234567890'::bytea placing '\002\003'::bytea from 2 for 3)</literal>
+        <returnvalue>\x12020390</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>position</primary>
+        </indexterm>
+        <function>position</function> ( <parameter>substring</parameter> <type>bytea</type> <literal>IN</literal> <parameter>bytes</parameter> <type>bytea</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns first starting index of the specified
+        <parameter>substring</parameter> within
+        <parameter>bytes</parameter>, or zero if it's not present.
+       </para>
+       <para>
+        <literal>position('\x5678'::bytea in '\x1234567890'::bytea)</literal>
+        <returnvalue>3</returnvalue>
+       </para></entry>
+      </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>rtrim</primary>
+         </indexterm>
+         <function>rtrim</function> ( <parameter>bytes</parameter> <type>bytea</type>,
+         <parameter>bytesremoved</parameter> <type>bytea</type> )
+         <returnvalue>bytea</returnvalue>
+        </para>
+        <para>
+         Removes the longest string containing only bytes appearing in
+         <parameter>bytesremoved</parameter> from the end of
+         <parameter>bytes</parameter>.
+        </para>
+        <para>
+         <literal>rtrim('\x1234567890'::bytea, '\x9012'::bytea)</literal>
+         <returnvalue>\x12345678</returnvalue>
+        </para></entry>
+       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>substring</primary>
+        </indexterm>
+        <function>substring</function> ( <parameter>bytes</parameter> <type>bytea</type> <optional> <literal>FROM</literal> <parameter>start</parameter> <type>integer</type> </optional> <optional> <literal>FOR</literal> <parameter>count</parameter> <type>integer</type> </optional> )
+        <returnvalue>bytea</returnvalue>
+       </para>
+       <para>
+        Extracts the substring of <parameter>bytes</parameter> starting at
+        the <parameter>start</parameter>'th byte if that is specified,
+        and stopping after <parameter>count</parameter> bytes if that is
+        specified.  Provide at least one of <parameter>start</parameter>
+        and <parameter>count</parameter>.
+       </para>
+       <para>
+        <literal>substring('\x1234567890'::bytea from 3 for 2)</literal>
+        <returnvalue>\x5678</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim</primary>
+        </indexterm>
+        <function>trim</function> ( <optional> <literal>LEADING</literal> | <literal>TRAILING</literal> | <literal>BOTH</literal> </optional>
+        <parameter>bytesremoved</parameter> <type>bytea</type> <literal>FROM</literal>
+        <parameter>bytes</parameter> <type>bytea</type> )
+        <returnvalue>bytea</returnvalue>
+       </para>
+       <para>
+        Removes the longest string containing only bytes appearing in
+        <parameter>bytesremoved</parameter> from the start,
+        end, or both ends (<literal>BOTH</literal> is the default)
+        of <parameter>bytes</parameter>.
+       </para>
+       <para>
+        <literal>trim('\x9012'::bytea from '\x1234567890'::bytea)</literal>
+        <returnvalue>\x345678</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>trim</function> ( <optional> <literal>LEADING</literal> | <literal>TRAILING</literal> | <literal>BOTH</literal> </optional> <optional> <literal>FROM</literal> </optional>
+        <parameter>bytes</parameter> <type>bytea</type>,
+        <parameter>bytesremoved</parameter> <type>bytea</type> )
+        <returnvalue>bytea</returnvalue>
+       </para>
+       <para>
+        This is a non-standard syntax for <function>trim()</function>.
+       </para>
+       <para>
+        <literal>trim(both from '\x1234567890'::bytea, '\x9012'::bytea)</literal>
+        <returnvalue>\x345678</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    Additional binary string manipulation functions are available and
+    are listed in <xref linkend="functions-binarystring-other"/>.  Some
+    of them are used internally to implement the
+    <acronym>SQL</acronym>-standard string functions listed in <xref
+    linkend="functions-binarystring-sql"/>.
+   </para>
+
+   <table id="functions-binarystring-other">
+    <title>Other Binary String Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>bit_count</primary>
+        </indexterm>
+        <indexterm>
+         <primary>popcount</primary>
+         <see>bit_count</see>
+        </indexterm>
+        <function>bit_count</function> ( <parameter>bytes</parameter> <type>bytea</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Returns the number of bits set in the binary string (also known as
+        <quote>popcount</quote>).
+       </para>
+       <para>
+        <literal>bit_count('\x1234567890'::bytea)</literal>
+        <returnvalue>15</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>crc32</primary>
+        </indexterm>
+        <function>crc32</function> ( <type>bytea</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Computes the CRC-32 value of the binary string.
+       </para>
+       <para>
+        <literal>crc32('abc'::bytea)</literal>
+        <returnvalue>891568578</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>crc32c</primary>
+        </indexterm>
+        <function>crc32c</function> ( <type>bytea</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Computes the CRC-32C value of the binary string.
+       </para>
+       <para>
+        <literal>crc32c('abc'::bytea)</literal>
+        <returnvalue>910901175</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>get_bit</primary>
+        </indexterm>
+        <function>get_bit</function> ( <parameter>bytes</parameter> <type>bytea</type>,
+        <parameter>n</parameter> <type>bigint</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Extracts <link linkend="functions-zerobased-note">n'th</link> bit
+        from binary string.
+       </para>
+       <para>
+        <literal>get_bit('\x1234567890'::bytea, 30)</literal>
+        <returnvalue>1</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>get_byte</primary>
+        </indexterm>
+        <function>get_byte</function> ( <parameter>bytes</parameter> <type>bytea</type>,
+        <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Extracts <link linkend="functions-zerobased-note">n'th</link> byte
+        from binary string.
+       </para>
+       <para>
+        <literal>get_byte('\x1234567890'::bytea, 4)</literal>
+        <returnvalue>144</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>length</primary>
+        </indexterm>
+        <indexterm>
+         <primary>binary string</primary>
+         <secondary>length</secondary>
+        </indexterm>
+        <indexterm>
+         <primary>length</primary>
+         <secondary sortas="binary string">of a binary string</secondary>
+         <see>binary strings, length</see>
+        </indexterm>
+        <function>length</function> ( <type>bytea</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the number of bytes in the binary string.
+       </para>
+       <para>
+        <literal>length('\x1234567890'::bytea)</literal>
+        <returnvalue>5</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>length</function> ( <parameter>bytes</parameter> <type>bytea</type>,
+        <parameter>encoding</parameter> <type>name</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the number of characters in the binary string, assuming
+        that it is text in the given <parameter>encoding</parameter>.
+       </para>
+       <para>
+        <literal>length('jose'::bytea, 'UTF8')</literal>
+        <returnvalue>4</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>md5</primary>
+        </indexterm>
+        <function>md5</function> ( <type>bytea</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Computes the MD5 <link linkend="functions-hash-note">hash</link> of
+        the binary string, with the result written in hexadecimal.
+       </para>
+       <para>
+        <literal>md5('Th\000omas'::bytea)</literal>
+        <returnvalue>8ab2d3c9689aaf18&zwsp;b4958c334c82d8b1</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>reverse</primary>
+        </indexterm>
+        <function>reverse</function> ( <type>bytea</type> )
+        <returnvalue>bytea</returnvalue>
+       </para>
+       <para>
+        Reverses the order of the bytes in the binary string.
+       </para>
+       <para>
+        <literal>reverse('\xabcd'::bytea)</literal>
+        <returnvalue>\xcdab</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>set_bit</primary>
+        </indexterm>
+        <function>set_bit</function> ( <parameter>bytes</parameter> <type>bytea</type>,
+        <parameter>n</parameter> <type>bigint</type>,
+        <parameter>newvalue</parameter> <type>integer</type> )
+        <returnvalue>bytea</returnvalue>
+       </para>
+       <para>
+        Sets <link linkend="functions-zerobased-note">n'th</link> bit in
+        binary string to <parameter>newvalue</parameter>.
+       </para>
+       <para>
+        <literal>set_bit('\x1234567890'::bytea, 30, 0)</literal>
+        <returnvalue>\x1234563890</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>set_byte</primary>
+        </indexterm>
+        <function>set_byte</function> ( <parameter>bytes</parameter> <type>bytea</type>,
+        <parameter>n</parameter> <type>integer</type>,
+        <parameter>newvalue</parameter> <type>integer</type> )
+        <returnvalue>bytea</returnvalue>
+       </para>
+       <para>
+        Sets <link linkend="functions-zerobased-note">n'th</link> byte in
+        binary string to <parameter>newvalue</parameter>.
+       </para>
+       <para>
+        <literal>set_byte('\x1234567890'::bytea, 4, 64)</literal>
+        <returnvalue>\x1234567840</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>sha224</primary>
+        </indexterm>
+        <function>sha224</function> ( <type>bytea</type> )
+        <returnvalue>bytea</returnvalue>
+       </para>
+       <para>
+        Computes the SHA-224 <link linkend="functions-hash-note">hash</link>
+        of the binary string.
+       </para>
+       <para>
+        <literal>sha224('abc'::bytea)</literal>
+        <returnvalue>\x23097d223405d8228642a477bda2&zwsp;55b32aadbce4bda0b3f7e36c9da7</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>sha256</primary>
+        </indexterm>
+        <function>sha256</function> ( <type>bytea</type> )
+        <returnvalue>bytea</returnvalue>
+       </para>
+       <para>
+        Computes the SHA-256 <link linkend="functions-hash-note">hash</link>
+        of the binary string.
+       </para>
+       <para>
+        <literal>sha256('abc'::bytea)</literal>
+        <returnvalue>\xba7816bf8f01cfea414140de5dae2223&zwsp;b00361a396177a9cb410ff61f20015ad</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>sha384</primary>
+        </indexterm>
+        <function>sha384</function> ( <type>bytea</type> )
+        <returnvalue>bytea</returnvalue>
+       </para>
+       <para>
+        Computes the SHA-384 <link linkend="functions-hash-note">hash</link>
+        of the binary string.
+       </para>
+       <para>
+        <literal>sha384('abc'::bytea)</literal>
+        <returnvalue>\xcb00753f45a35e8bb5a03d699ac65007&zwsp;272c32ab0eded1631a8b605a43ff5bed&zwsp;8086072ba1e7cc2358baeca134c825a7</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>sha512</primary>
+        </indexterm>
+        <function>sha512</function> ( <type>bytea</type> )
+        <returnvalue>bytea</returnvalue>
+       </para>
+       <para>
+        Computes the SHA-512 <link linkend="functions-hash-note">hash</link>
+        of the binary string.
+       </para>
+       <para>
+        <literal>sha512('abc'::bytea)</literal>
+        <returnvalue>\xddaf35a193617abacc417349ae204131&zwsp;12e6fa4e89a97ea20a9eeee64b55d39a&zwsp;2192992a274fc1a836ba3c23a3feebbd&zwsp;454d4423643ce80e2a9ac94fa54ca49f</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>substr</primary>
+        </indexterm>
+        <function>substr</function> ( <parameter>bytes</parameter> <type>bytea</type>, <parameter>start</parameter> <type>integer</type> <optional>, <parameter>count</parameter> <type>integer</type> </optional> )
+        <returnvalue>bytea</returnvalue>
+       </para>
+       <para>
+        Extracts the substring of <parameter>bytes</parameter> starting at
+        the <parameter>start</parameter>'th byte,
+        and extending for <parameter>count</parameter> bytes if that is
+        specified.  (Same
+        as <literal>substring(<parameter>bytes</parameter>
+        from <parameter>start</parameter>
+        for <parameter>count</parameter>)</literal>.)
+       </para>
+       <para>
+        <literal>substr('\x1234567890'::bytea, 3, 2)</literal>
+        <returnvalue>\x5678</returnvalue>
+       </para></entry>
+      </row>
+    </tbody>
+   </tgroup>
+  </table>
+
+  <para id="functions-zerobased-note">
+   Functions <function>get_byte</function> and <function>set_byte</function>
+   number the first byte of a binary string as byte 0.
+   Functions <function>get_bit</function> and <function>set_bit</function>
+   number bits from the right within each byte; for example bit 0 is the least
+   significant bit of the first byte, and bit 15 is the most significant bit
+   of the second byte.
+  </para>
+
+  <para id="functions-hash-note">
+   For historical reasons, the function <function>md5</function>
+   returns a hex-encoded value of type <type>text</type> whereas the SHA-2
+   functions return type <type>bytea</type>.  Use the functions
+   <link linkend="function-encode"><function>encode</function></link>
+   and <link linkend="function-decode"><function>decode</function></link> to
+   convert between the two.  For example write <literal>encode(sha256('abc'),
+   'hex')</literal> to get a hex-encoded text representation,
+   or <literal>decode(md5('abc'), 'hex')</literal> to get
+   a <type>bytea</type> value.
+  </para>
+
+  <para>
+   <indexterm>
+    <primary>character string</primary>
+    <secondary>converting to binary string</secondary>
+   </indexterm>
+   <indexterm>
+    <primary>binary string</primary>
+    <secondary>converting to character string</secondary>
+   </indexterm>
+   Functions for converting strings between different character sets
+   (encodings), and for representing arbitrary binary data in textual
+   form, are shown in
+   <xref linkend="functions-binarystring-conversions"/>.  For these
+   functions, an argument or result of type <type>text</type> is expressed
+   in the database's default encoding, while arguments or results of
+   type <type>bytea</type> are in an encoding named by another argument.
+  </para>
+
+  <table id="functions-binarystring-conversions">
+   <title>Text/Binary String Conversion Functions</title>
+   <tgroup cols="1">
+    <thead>
+     <row>
+      <entry role="func_table_entry"><para role="func_signature">
+       Function
+      </para>
+      <para>
+       Description
+      </para>
+      <para>
+       Example(s)
+      </para></entry>
+     </row>
+    </thead>
+
+    <tbody>
+     <row>
+      <entry role="func_table_entry"><para role="func_signature">
+       <indexterm>
+        <primary>convert</primary>
+       </indexterm>
+       <function>convert</function> ( <parameter>bytes</parameter> <type>bytea</type>,
+       <parameter>src_encoding</parameter> <type>name</type>,
+       <parameter>dest_encoding</parameter> <type>name</type> )
+       <returnvalue>bytea</returnvalue>
+      </para>
+      <para>
+       Converts a binary string representing text in
+       encoding <parameter>src_encoding</parameter>
+       to a binary string in encoding <parameter>dest_encoding</parameter>
+       (see <xref linkend="multibyte-conversions-supported"/> for
+       available conversions).
+      </para>
+      <para>
+       <literal>convert('text_in_utf8', 'UTF8', 'LATIN1')</literal>
+       <returnvalue>\x746578745f696e5f75746638</returnvalue>
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="func_table_entry"><para role="func_signature">
+       <indexterm>
+        <primary>convert_from</primary>
+       </indexterm>
+       <function>convert_from</function> ( <parameter>bytes</parameter> <type>bytea</type>,
+       <parameter>src_encoding</parameter> <type>name</type> )
+       <returnvalue>text</returnvalue>
+      </para>
+      <para>
+       Converts a binary string representing text in
+       encoding <parameter>src_encoding</parameter>
+       to <type>text</type> in the database encoding
+       (see <xref linkend="multibyte-conversions-supported"/> for
+       available conversions).
+      </para>
+      <para>
+       <literal>convert_from('text_in_utf8', 'UTF8')</literal>
+       <returnvalue>text_in_utf8</returnvalue>
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="func_table_entry"><para role="func_signature">
+       <indexterm>
+        <primary>convert_to</primary>
+       </indexterm>
+       <function>convert_to</function> ( <parameter>string</parameter> <type>text</type>,
+       <parameter>dest_encoding</parameter> <type>name</type> )
+       <returnvalue>bytea</returnvalue>
+      </para>
+      <para>
+       Converts a <type>text</type> string (in the database encoding) to a
+       binary string encoded in encoding <parameter>dest_encoding</parameter>
+       (see <xref linkend="multibyte-conversions-supported"/> for
+       available conversions).
+      </para>
+      <para>
+       <literal>convert_to('some_text', 'UTF8')</literal>
+       <returnvalue>\x736f6d655f74657874</returnvalue>
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="func_table_entry"><para role="func_signature">
+       <indexterm id="function-encode">
+        <primary>encode</primary>
+       </indexterm>
+       <function>encode</function> ( <parameter>bytes</parameter> <type>bytea</type>,
+       <parameter>format</parameter> <type>text</type> )
+       <returnvalue>text</returnvalue>
+      </para>
+      <para>
+       Encodes binary data into a textual representation; supported
+       <parameter>format</parameter> values are:
+       <link linkend="encode-format-base64"><literal>base64</literal></link>,
+       <link linkend="encode-format-escape"><literal>escape</literal></link>,
+       <link linkend="encode-format-hex"><literal>hex</literal></link>.
+      </para>
+      <para>
+       <literal>encode('123\000\001', 'base64')</literal>
+       <returnvalue>MTIzAAE=</returnvalue>
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="func_table_entry"><para role="func_signature">
+       <indexterm id="function-decode">
+        <primary>decode</primary>
+       </indexterm>
+       <function>decode</function> ( <parameter>string</parameter> <type>text</type>,
+       <parameter>format</parameter> <type>text</type> )
+       <returnvalue>bytea</returnvalue>
+      </para>
+      <para>
+       Decodes binary data from a textual representation; supported
+       <parameter>format</parameter> values are the same as
+       for <function>encode</function>.
+      </para>
+      <para>
+       <literal>decode('MTIzAAE=', 'base64')</literal>
+       <returnvalue>\x3132330001</returnvalue>
+      </para></entry>
+     </row>
+    </tbody>
+   </tgroup>
+  </table>
+
+  <para>
+   The <function>encode</function> and <function>decode</function>
+   functions support the following textual formats:
+
+   <variablelist>
+    <varlistentry id="encode-format-base64">
+     <term>base64
+     <indexterm>
+      <primary>base64 format</primary>
+     </indexterm></term>
+     <listitem>
+      <para>
+       The <literal>base64</literal> format is that
+       of <ulink url="https://datatracker.ietf.org/doc/html/rfc2045#section-6.8">RFC
+       2045 Section 6.8</ulink>.  As per the <acronym>RFC</acronym>, encoded lines are
+       broken at 76 characters.  However instead of the MIME CRLF
+       end-of-line marker, only a newline is used for end-of-line.
+       The <function>decode</function> function ignores carriage-return,
+       newline, space, and tab characters.  Otherwise, an error is
+       raised when <function>decode</function> is supplied invalid
+       base64 data &mdash; including when trailing padding is incorrect.
+      </para>
+     </listitem>
+    </varlistentry>
+
+    <varlistentry id="encode-format-escape">
+     <term>escape
+     <indexterm>
+      <primary>escape format</primary>
+     </indexterm></term>
+     <listitem>
+      <para>
+       The <literal>escape</literal> format converts zero bytes and
+       bytes with the high bit set into octal escape sequences
+       (<literal>\</literal><replaceable>nnn</replaceable>), and it doubles
+       backslashes.  Other byte values are represented literally.
+       The <function>decode</function> function will raise an error if a
+       backslash is not followed by either a second backslash or three
+       octal digits; it accepts other byte values unchanged.
+      </para>
+     </listitem>
+    </varlistentry>
+
+    <varlistentry id="encode-format-hex">
+     <term>hex
+     <indexterm>
+      <primary>hex format</primary>
+     </indexterm></term>
+     <listitem>
+      <para>
+       The <literal>hex</literal> format represents each 4 bits of
+       data as one hexadecimal digit, <literal>0</literal>
+       through <literal>f</literal>, writing the higher-order digit of
+       each byte first.  The <function>encode</function> function outputs
+       the <literal>a</literal>-<literal>f</literal> hex digits in lower
+       case.  Because the smallest unit of data is 8 bits, there are
+       always an even number of characters returned
+       by <function>encode</function>.
+       The <function>decode</function> function
+       accepts the <literal>a</literal>-<literal>f</literal> characters in
+       either upper or lower case.  An error is raised
+       when <function>decode</function> is given invalid hex data
+       &mdash; including when given an odd number of characters.
+      </para>
+     </listitem>
+    </varlistentry>
+   </variablelist>
+  </para>
+
+  <para>
+   In addition, it is possible to cast integral values to and from type
+   <type>bytea</type>. Casting an integer to <type>bytea</type> produces
+   2, 4, or 8 bytes, depending on the width of the integer type. The result
+   is the two's complement representation of the integer, with the most
+   significant byte first. Some examples:
+<programlisting>
+1234::smallint::bytea          <lineannotation>\x04d2</lineannotation>
+cast(1234 as bytea)            <lineannotation>\x000004d2</lineannotation>
+cast(-1234 as bytea)           <lineannotation>\xfffffb2e</lineannotation>
+'\x8000'::bytea::smallint      <lineannotation>-32768</lineannotation>
+'\x8000'::bytea::integer       <lineannotation>32768</lineannotation>
+</programlisting>
+   Casting a <type>bytea</type> to an integer will raise an error if the
+   length of the <type>bytea</type> exceeds the width of the integer type.
+  </para>
+
+  <para>
+   See also the aggregate function <function>string_agg</function> in
+   <xref linkend="functions-aggregate"/> and the large object functions
+   in <xref linkend="lo-funcs"/>.
+  </para>
+ </sect1>
diff --git a/doc/src/sgml/func/func-bitstring.sgml b/doc/src/sgml/func/func-bitstring.sgml
new file mode 100644
index 0000000000000..f03dd63afcc6a
--- /dev/null
+++ b/doc/src/sgml/func/func-bitstring.sgml
@@ -0,0 +1,358 @@
+  <sect1 id="functions-bitstring">
+   <title>Bit String Functions and Operators</title>
+
+   <indexterm zone="functions-bitstring">
+    <primary>bit strings</primary>
+    <secondary>functions</secondary>
+   </indexterm>
+
+   <para>
+    This section describes functions and operators for examining and
+    manipulating bit strings, that is values of the types
+    <type>bit</type> and <type>bit varying</type>.  (While only
+    type <type>bit</type> is mentioned in these tables, values of
+    type <type>bit varying</type> can be used interchangeably.)
+    Bit strings support the usual comparison operators shown in
+    <xref linkend="functions-comparison-op-table"/>, as well as the
+    operators shown in <xref linkend="functions-bit-string-op-table"/>.
+   </para>
+
+   <table id="functions-bit-string-op-table">
+    <title>Bit String Operators</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Operator
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>bit</type> <literal>||</literal> <type>bit</type>
+        <returnvalue>bit</returnvalue>
+       </para>
+       <para>
+        Concatenation
+       </para>
+       <para>
+        <literal>B'10001' || B'011'</literal>
+        <returnvalue>10001011</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>bit</type> <literal>&amp;</literal> <type>bit</type>
+        <returnvalue>bit</returnvalue>
+       </para>
+       <para>
+        Bitwise AND (inputs must be of equal length)
+       </para>
+       <para>
+        <literal>B'10001' &amp; B'01101'</literal>
+        <returnvalue>00001</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>bit</type> <literal>|</literal> <type>bit</type>
+        <returnvalue>bit</returnvalue>
+       </para>
+       <para>
+        Bitwise OR (inputs must be of equal length)
+       </para>
+       <para>
+        <literal>B'10001' | B'01101'</literal>
+        <returnvalue>11101</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>bit</type> <literal>#</literal> <type>bit</type>
+        <returnvalue>bit</returnvalue>
+       </para>
+       <para>
+        Bitwise exclusive OR (inputs must be of equal length)
+       </para>
+       <para>
+        <literal>B'10001' # B'01101'</literal>
+        <returnvalue>11100</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>~</literal> <type>bit</type>
+        <returnvalue>bit</returnvalue>
+       </para>
+       <para>
+        Bitwise NOT
+       </para>
+       <para>
+        <literal>~ B'10001'</literal>
+        <returnvalue>01110</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>bit</type> <literal>&lt;&lt;</literal> <type>integer</type>
+        <returnvalue>bit</returnvalue>
+       </para>
+       <para>
+        Bitwise shift left
+        (string length is preserved)
+       </para>
+       <para>
+        <literal>B'10001' &lt;&lt; 3</literal>
+        <returnvalue>01000</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>bit</type> <literal>&gt;&gt;</literal> <type>integer</type>
+        <returnvalue>bit</returnvalue>
+       </para>
+       <para>
+        Bitwise shift right
+        (string length is preserved)
+       </para>
+       <para>
+        <literal>B'10001' &gt;&gt; 2</literal>
+        <returnvalue>00100</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    Some of the functions available for binary strings are also available
+    for bit strings, as shown in <xref linkend="functions-bit-string-table"/>.
+   </para>
+
+   <table id="functions-bit-string-table">
+    <title>Bit String Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>bit_count</primary>
+        </indexterm>
+        <function>bit_count</function> ( <type>bit</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Returns the number of bits set in the bit string (also known as
+        <quote>popcount</quote>).
+       </para>
+       <para>
+        <literal>bit_count(B'10111')</literal>
+        <returnvalue>4</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>bit_length</primary>
+        </indexterm>
+        <function>bit_length</function> ( <type>bit</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns number of bits in the bit string.
+       </para>
+       <para>
+        <literal>bit_length(B'10111')</literal>
+        <returnvalue>5</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>length</primary>
+        </indexterm>
+        <indexterm>
+         <primary>bit string</primary>
+         <secondary>length</secondary>
+        </indexterm>
+        <function>length</function> ( <type>bit</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns number of bits in the bit string.
+       </para>
+       <para>
+        <literal>length(B'10111')</literal>
+        <returnvalue>5</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>octet_length</primary>
+        </indexterm>
+        <function>octet_length</function> ( <type>bit</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns number of bytes in the bit string.
+       </para>
+       <para>
+        <literal>octet_length(B'1011111011')</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>overlay</primary>
+        </indexterm>
+        <function>overlay</function> ( <parameter>bits</parameter> <type>bit</type> <literal>PLACING</literal> <parameter>newsubstring</parameter> <type>bit</type> <literal>FROM</literal> <parameter>start</parameter> <type>integer</type> <optional> <literal>FOR</literal> <parameter>count</parameter> <type>integer</type> </optional> )
+        <returnvalue>bit</returnvalue>
+       </para>
+       <para>
+        Replaces the substring of <parameter>bits</parameter> that starts at
+        the <parameter>start</parameter>'th bit and extends
+        for <parameter>count</parameter> bits
+        with <parameter>newsubstring</parameter>.
+        If <parameter>count</parameter> is omitted, it defaults to the length
+        of <parameter>newsubstring</parameter>.
+       </para>
+       <para>
+        <literal>overlay(B'01010101010101010' placing B'11111' from 2 for 3)</literal>
+        <returnvalue>0111110101010101010</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>position</primary>
+        </indexterm>
+        <function>position</function> ( <parameter>substring</parameter> <type>bit</type> <literal>IN</literal> <parameter>bits</parameter> <type>bit</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns first starting index of the specified <parameter>substring</parameter>
+        within <parameter>bits</parameter>, or zero if it's not present.
+       </para>
+       <para>
+        <literal>position(B'010' in B'000001101011')</literal>
+        <returnvalue>8</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>substring</primary>
+        </indexterm>
+        <function>substring</function> ( <parameter>bits</parameter> <type>bit</type> <optional> <literal>FROM</literal> <parameter>start</parameter> <type>integer</type> </optional> <optional> <literal>FOR</literal> <parameter>count</parameter> <type>integer</type> </optional> )
+        <returnvalue>bit</returnvalue>
+       </para>
+       <para>
+        Extracts the substring of <parameter>bits</parameter> starting at
+        the <parameter>start</parameter>'th bit if that is specified,
+        and stopping after <parameter>count</parameter> bits if that is
+        specified.  Provide at least one of <parameter>start</parameter>
+        and <parameter>count</parameter>.
+       </para>
+       <para>
+        <literal>substring(B'110010111111' from 3 for 2)</literal>
+        <returnvalue>00</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>get_bit</primary>
+        </indexterm>
+        <function>get_bit</function> ( <parameter>bits</parameter> <type>bit</type>,
+        <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Extracts <parameter>n</parameter>'th bit
+        from bit string; the first (leftmost) bit is bit 0.
+       </para>
+       <para>
+        <literal>get_bit(B'101010101010101010', 6)</literal>
+        <returnvalue>1</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>set_bit</primary>
+        </indexterm>
+        <function>set_bit</function> ( <parameter>bits</parameter> <type>bit</type>,
+        <parameter>n</parameter> <type>integer</type>,
+        <parameter>newvalue</parameter> <type>integer</type> )
+        <returnvalue>bit</returnvalue>
+       </para>
+       <para>
+        Sets <parameter>n</parameter>'th bit in
+        bit string to <parameter>newvalue</parameter>;
+        the first (leftmost) bit is bit 0.
+       </para>
+       <para>
+        <literal>set_bit(B'101010101010101010', 6, 0)</literal>
+        <returnvalue>101010001010101010</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    In addition, it is possible to cast integral values to and from type
+    <type>bit</type>.
+    Casting an integer to <type>bit(n)</type> copies the rightmost
+    <literal>n</literal> bits.  Casting an integer to a bit string width wider
+    than the integer itself will sign-extend on the left.
+    Some examples:
+<programlisting>
+44::bit(10)                    <lineannotation>0000101100</lineannotation>
+44::bit(3)                     <lineannotation>100</lineannotation>
+cast(-44 as bit(12))           <lineannotation>111111010100</lineannotation>
+'1110'::bit(4)::integer        <lineannotation>14</lineannotation>
+</programlisting>
+    Note that casting to just <quote>bit</quote> means casting to
+    <literal>bit(1)</literal>, and so will deliver only the least significant
+    bit of the integer.
+   </para>
+  </sect1>
diff --git a/doc/src/sgml/func/func-comparison.sgml b/doc/src/sgml/func/func-comparison.sgml
new file mode 100644
index 0000000000000..c1205983f8bac
--- /dev/null
+++ b/doc/src/sgml/func/func-comparison.sgml
@@ -0,0 +1,638 @@
+  <sect1 id="functions-comparison">
+   <title>Comparison Functions and Operators</title>
+
+   <indexterm zone="functions-comparison">
+    <primary>comparison</primary>
+    <secondary>operators</secondary>
+   </indexterm>
+
+   <para>
+    The usual comparison operators are available, as shown in <xref
+    linkend="functions-comparison-op-table"/>.
+   </para>
+
+   <table id="functions-comparison-op-table">
+    <title>Comparison Operators</title>
+    <tgroup cols="2">
+     <thead>
+      <row>
+       <entry>Operator</entry>
+       <entry>Description</entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry>
+        <replaceable>datatype</replaceable> <literal>&lt;</literal> <replaceable>datatype</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </entry>
+       <entry>Less than</entry>
+      </row>
+
+      <row>
+       <entry>
+        <replaceable>datatype</replaceable> <literal>&gt;</literal> <replaceable>datatype</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </entry>
+       <entry>Greater than</entry>
+      </row>
+
+      <row>
+       <entry>
+        <replaceable>datatype</replaceable> <literal>&lt;=</literal> <replaceable>datatype</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </entry>
+       <entry>Less than or equal to</entry>
+      </row>
+
+      <row>
+       <entry>
+        <replaceable>datatype</replaceable> <literal>&gt;=</literal> <replaceable>datatype</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </entry>
+       <entry>Greater than or equal to</entry>
+      </row>
+
+      <row>
+       <entry>
+        <replaceable>datatype</replaceable> <literal>=</literal> <replaceable>datatype</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </entry>
+       <entry>Equal</entry>
+      </row>
+
+      <row>
+       <entry>
+        <replaceable>datatype</replaceable> <literal>&lt;&gt;</literal> <replaceable>datatype</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </entry>
+       <entry>Not equal</entry>
+      </row>
+
+      <row>
+       <entry>
+        <replaceable>datatype</replaceable> <literal>!=</literal> <replaceable>datatype</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </entry>
+       <entry>Not equal</entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <note>
+    <para>
+     <literal>&lt;&gt;</literal> is the standard SQL notation for <quote>not
+     equal</quote>.  <literal>!=</literal> is an alias, which is converted
+     to <literal>&lt;&gt;</literal> at a very early stage of parsing.
+     Hence, it is not possible to implement <literal>!=</literal>
+     and <literal>&lt;&gt;</literal> operators that do different things.
+    </para>
+   </note>
+
+   <para>
+    These comparison operators are available for all built-in data types
+    that have a natural ordering, including numeric, string, and date/time
+    types.  In addition, arrays, composite types, and ranges can be compared
+    if their component data types are comparable.
+   </para>
+
+   <para>
+    It is usually possible to compare values of related data
+    types as well; for example <type>integer</type> <literal>&gt;</literal>
+    <type>bigint</type> will work.  Some cases of this sort are implemented
+    directly by <quote>cross-type</quote> comparison operators, but if no
+    such operator is available, the parser will coerce the less-general type
+    to the more-general type and apply the latter's comparison operator.
+   </para>
+
+   <para>
+    As shown above, all comparison operators are binary operators that
+    return values of type <type>boolean</type>.  Thus, expressions like
+    <literal>1 &lt; 2 &lt; 3</literal> are not valid (because there is
+    no <literal>&lt;</literal> operator to compare a Boolean value with
+    <literal>3</literal>).  Use the <literal>BETWEEN</literal> predicates
+    shown below to perform range tests.
+   </para>
+
+   <para>
+    There are also some comparison predicates, as shown in <xref
+    linkend="functions-comparison-pred-table"/>.  These behave much like
+    operators, but have special syntax mandated by the SQL standard.
+   </para>
+
+   <table id="functions-comparison-pred-table">
+    <title>Comparison Predicates</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Predicate
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>datatype</replaceable> <literal>BETWEEN</literal> <replaceable>datatype</replaceable> <literal>AND</literal> <replaceable>datatype</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Between (inclusive of the range endpoints).
+       </para>
+       <para>
+        <literal>2 BETWEEN 1 AND 3</literal>
+        <returnvalue>t</returnvalue>
+       </para>
+       <para>
+        <literal>2 BETWEEN 3 AND 1</literal>
+        <returnvalue>f</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>datatype</replaceable> <literal>NOT BETWEEN</literal> <replaceable>datatype</replaceable> <literal>AND</literal> <replaceable>datatype</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Not between (the negation of <literal>BETWEEN</literal>).
+       </para>
+       <para>
+        <literal>2 NOT BETWEEN 1 AND 3</literal>
+        <returnvalue>f</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>datatype</replaceable> <literal>BETWEEN SYMMETRIC</literal> <replaceable>datatype</replaceable> <literal>AND</literal> <replaceable>datatype</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Between, after sorting the two endpoint values.
+       </para>
+       <para>
+        <literal>2 BETWEEN SYMMETRIC 3 AND 1</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>datatype</replaceable> <literal>NOT BETWEEN SYMMETRIC</literal> <replaceable>datatype</replaceable> <literal>AND</literal> <replaceable>datatype</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Not between, after sorting the two endpoint values.
+       </para>
+       <para>
+        <literal>2 NOT BETWEEN SYMMETRIC 3 AND 1</literal>
+        <returnvalue>f</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>datatype</replaceable> <literal>IS DISTINCT FROM</literal> <replaceable>datatype</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Not equal, treating null as a comparable value.
+       </para>
+       <para>
+        <literal>1 IS DISTINCT FROM NULL</literal>
+        <returnvalue>t</returnvalue> (rather than <literal>NULL</literal>)
+       </para>
+       <para>
+        <literal>NULL IS DISTINCT FROM NULL</literal>
+        <returnvalue>f</returnvalue> (rather than <literal>NULL</literal>)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>datatype</replaceable> <literal>IS NOT DISTINCT FROM</literal> <replaceable>datatype</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Equal, treating null as a comparable value.
+       </para>
+       <para>
+        <literal>1 IS NOT DISTINCT FROM NULL</literal>
+        <returnvalue>f</returnvalue> (rather than <literal>NULL</literal>)
+       </para>
+       <para>
+        <literal>NULL IS NOT DISTINCT FROM NULL</literal>
+        <returnvalue>t</returnvalue> (rather than <literal>NULL</literal>)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>datatype</replaceable> <literal>IS NULL</literal>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Test whether value is null.
+       </para>
+       <para>
+        <literal>1.5 IS NULL</literal>
+        <returnvalue>f</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>datatype</replaceable> <literal>IS NOT NULL</literal>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Test whether value is not null.
+       </para>
+       <para>
+        <literal>'null' IS NOT NULL</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>datatype</replaceable> <literal>ISNULL</literal>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Test whether value is null (nonstandard syntax).
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>datatype</replaceable> <literal>NOTNULL</literal>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Test whether value is not null (nonstandard syntax).
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>boolean</type> <literal>IS TRUE</literal>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Test whether boolean expression yields true.
+       </para>
+       <para>
+        <literal>true IS TRUE</literal>
+        <returnvalue>t</returnvalue>
+       </para>
+       <para>
+        <literal>NULL::boolean IS TRUE</literal>
+        <returnvalue>f</returnvalue> (rather than <literal>NULL</literal>)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>boolean</type> <literal>IS NOT TRUE</literal>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Test whether boolean expression yields false or unknown.
+       </para>
+       <para>
+        <literal>true IS NOT TRUE</literal>
+        <returnvalue>f</returnvalue>
+       </para>
+       <para>
+        <literal>NULL::boolean IS NOT TRUE</literal>
+        <returnvalue>t</returnvalue> (rather than <literal>NULL</literal>)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>boolean</type> <literal>IS FALSE</literal>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Test whether boolean expression yields false.
+       </para>
+       <para>
+        <literal>true IS FALSE</literal>
+        <returnvalue>f</returnvalue>
+       </para>
+       <para>
+        <literal>NULL::boolean IS FALSE</literal>
+        <returnvalue>f</returnvalue> (rather than <literal>NULL</literal>)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>boolean</type> <literal>IS NOT FALSE</literal>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Test whether boolean expression yields true or unknown.
+       </para>
+       <para>
+        <literal>true IS NOT FALSE</literal>
+        <returnvalue>t</returnvalue>
+       </para>
+       <para>
+        <literal>NULL::boolean IS NOT FALSE</literal>
+        <returnvalue>t</returnvalue> (rather than <literal>NULL</literal>)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>boolean</type> <literal>IS UNKNOWN</literal>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Test whether boolean expression yields unknown.
+       </para>
+       <para>
+        <literal>true IS UNKNOWN</literal>
+        <returnvalue>f</returnvalue>
+       </para>
+       <para>
+        <literal>NULL::boolean IS UNKNOWN</literal>
+        <returnvalue>t</returnvalue> (rather than <literal>NULL</literal>)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>boolean</type> <literal>IS NOT UNKNOWN</literal>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Test whether boolean expression yields true or false.
+       </para>
+       <para>
+        <literal>true IS NOT UNKNOWN</literal>
+        <returnvalue>t</returnvalue>
+       </para>
+       <para>
+        <literal>NULL::boolean IS NOT UNKNOWN</literal>
+        <returnvalue>f</returnvalue> (rather than <literal>NULL</literal>)
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    <indexterm>
+     <primary>BETWEEN</primary>
+    </indexterm>
+    <indexterm>
+     <primary>BETWEEN SYMMETRIC</primary>
+    </indexterm>
+    The <token>BETWEEN</token> predicate simplifies range tests:
+<synopsis>
+<replaceable>a</replaceable> BETWEEN <replaceable>x</replaceable> AND <replaceable>y</replaceable>
+</synopsis>
+    is equivalent to
+<synopsis>
+<replaceable>a</replaceable> &gt;= <replaceable>x</replaceable> AND <replaceable>a</replaceable> &lt;= <replaceable>y</replaceable>
+</synopsis>
+    Notice that <token>BETWEEN</token> treats the endpoint values as included
+    in the range.
+    <literal>BETWEEN SYMMETRIC</literal> is like <literal>BETWEEN</literal>
+    except there is no requirement that the argument to the left of
+    <literal>AND</literal> be less than or equal to the argument on the right.
+    If it is not, those two arguments are automatically swapped, so that
+    a nonempty range is always implied.
+   </para>
+
+   <para>
+    The various variants of <literal>BETWEEN</literal> are implemented in
+    terms of the ordinary comparison operators, and therefore will work for
+    any data type(s) that can be compared.
+   </para>
+
+   <note>
+    <para>
+     The use of <literal>AND</literal> in the <literal>BETWEEN</literal>
+     syntax creates an ambiguity with the use of <literal>AND</literal> as a
+     logical operator.  To resolve this, only a limited set of expression
+     types are allowed as the second argument of a <literal>BETWEEN</literal>
+     clause.  If you need to write a more complex sub-expression
+     in <literal>BETWEEN</literal>, write parentheses around the
+     sub-expression.
+    </para>
+   </note>
+
+   <para>
+    <indexterm>
+     <primary>IS DISTINCT FROM</primary>
+    </indexterm>
+    <indexterm>
+     <primary>IS NOT DISTINCT FROM</primary>
+    </indexterm>
+    Ordinary comparison operators yield null (signifying <quote>unknown</quote>),
+    not true or false, when either input is null.  For example,
+    <literal>7 = NULL</literal> yields null, as does <literal>7 &lt;&gt; NULL</literal>.  When
+    this behavior is not suitable, use the
+    <literal>IS <optional> NOT </optional> DISTINCT FROM</literal> predicates:
+<synopsis>
+<replaceable>a</replaceable> IS DISTINCT FROM <replaceable>b</replaceable>
+<replaceable>a</replaceable> IS NOT DISTINCT FROM <replaceable>b</replaceable>
+</synopsis>
+    For non-null inputs, <literal>IS DISTINCT FROM</literal> is
+    the same as the <literal>&lt;&gt;</literal> operator.  However, if both
+    inputs are null it returns false, and if only one input is
+    null it returns true.  Similarly, <literal>IS NOT DISTINCT
+    FROM</literal> is identical to <literal>=</literal> for non-null
+    inputs, but it returns true when both inputs are null, and false when only
+    one input is null. Thus, these predicates effectively act as though null
+    were a normal data value, rather than <quote>unknown</quote>.
+   </para>
+
+   <para>
+    <indexterm>
+     <primary>IS NULL</primary>
+    </indexterm>
+    <indexterm>
+     <primary>IS NOT NULL</primary>
+    </indexterm>
+    <indexterm>
+     <primary>ISNULL</primary>
+    </indexterm>
+    <indexterm>
+     <primary>NOTNULL</primary>
+    </indexterm>
+    To check whether a value is or is not null, use the predicates:
+<synopsis>
+<replaceable>expression</replaceable> IS NULL
+<replaceable>expression</replaceable> IS NOT NULL
+</synopsis>
+    or the equivalent, but nonstandard, predicates:
+<synopsis>
+<replaceable>expression</replaceable> ISNULL
+<replaceable>expression</replaceable> NOTNULL
+</synopsis>
+    <indexterm><primary>null value</primary><secondary>comparing</secondary></indexterm>
+   </para>
+
+   <para>
+    Do <emphasis>not</emphasis> write
+    <literal><replaceable>expression</replaceable> = NULL</literal>
+    because <literal>NULL</literal> is not <quote>equal to</quote>
+    <literal>NULL</literal>.  (The null value represents an unknown value,
+    and it is not known whether two unknown values are equal.)
+   </para>
+
+  <tip>
+   <para>
+    Some applications might expect that
+    <literal><replaceable>expression</replaceable> = NULL</literal>
+    returns true if <replaceable>expression</replaceable> evaluates to
+    the null value.  It is highly recommended that these applications
+    be modified to comply with the SQL standard. However, if that
+    cannot be done the <xref linkend="guc-transform-null-equals"/>
+    configuration variable is available. If it is enabled,
+    <productname>PostgreSQL</productname> will convert <literal>x =
+    NULL</literal> clauses to <literal>x IS NULL</literal>.
+   </para>
+  </tip>
+
+   <para>
+    If the <replaceable>expression</replaceable> is row-valued, then
+    <literal>IS NULL</literal> is true when the row expression itself is null
+    or when all the row's fields are null, while
+    <literal>IS NOT NULL</literal> is true when the row expression itself is non-null
+    and all the row's fields are non-null.  Because of this behavior,
+    <literal>IS NULL</literal> and <literal>IS NOT NULL</literal> do not always return
+    inverse results for row-valued expressions; in particular, a row-valued
+    expression that contains both null and non-null fields will return false
+    for both tests.  For example:
+
+<programlisting>
+SELECT ROW(1,2.5,'this is a test') = ROW(1, 3, 'not the same');
+
+SELECT ROW(table.*) IS NULL FROM table;  -- detect all-null rows
+
+SELECT ROW(table.*) IS NOT NULL FROM table;  -- detect all-non-null rows
+
+SELECT NOT(ROW(table.*) IS NOT NULL) FROM TABLE; -- detect at least one null in rows
+</programlisting>
+
+    In some cases, it may be preferable to
+    write <replaceable>row</replaceable> <literal>IS DISTINCT FROM NULL</literal>
+    or <replaceable>row</replaceable> <literal>IS NOT DISTINCT FROM NULL</literal>,
+    which will simply check whether the overall row value is null without any
+    additional tests on the row fields.
+   </para>
+
+   <para>
+    <indexterm>
+     <primary>IS TRUE</primary>
+    </indexterm>
+    <indexterm>
+     <primary>IS NOT TRUE</primary>
+    </indexterm>
+    <indexterm>
+     <primary>IS FALSE</primary>
+    </indexterm>
+    <indexterm>
+     <primary>IS NOT FALSE</primary>
+    </indexterm>
+    <indexterm>
+     <primary>IS UNKNOWN</primary>
+    </indexterm>
+    <indexterm>
+     <primary>IS NOT UNKNOWN</primary>
+    </indexterm>
+    Boolean values can also be tested using the predicates
+<synopsis>
+<replaceable>boolean_expression</replaceable> IS TRUE
+<replaceable>boolean_expression</replaceable> IS NOT TRUE
+<replaceable>boolean_expression</replaceable> IS FALSE
+<replaceable>boolean_expression</replaceable> IS NOT FALSE
+<replaceable>boolean_expression</replaceable> IS UNKNOWN
+<replaceable>boolean_expression</replaceable> IS NOT UNKNOWN
+</synopsis>
+    These will always return true or false, never a null value, even when the
+    operand is null.
+    A null input is treated as the logical value <quote>unknown</quote>.
+    Notice that <literal>IS UNKNOWN</literal> and <literal>IS NOT UNKNOWN</literal> are
+    effectively the same as <literal>IS NULL</literal> and
+    <literal>IS NOT NULL</literal>, respectively, except that the input
+    expression must be of Boolean type.
+   </para>
+
+   <para>
+    Some comparison-related functions are also available, as shown in <xref
+    linkend="functions-comparison-func-table"/>.
+   </para>
+
+  <table id="functions-comparison-func-table">
+    <title>Comparison Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>num_nonnulls</primary>
+        </indexterm>
+        <function>num_nonnulls</function> ( <literal>VARIADIC</literal> <type>"any"</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the number of non-null arguments.
+       </para>
+       <para>
+        <literal>num_nonnulls(1, NULL, 2)</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>num_nulls</primary>
+        </indexterm>
+        <function>num_nulls</function> ( <literal>VARIADIC</literal> <type>"any"</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the number of null arguments.
+       </para>
+       <para>
+        <literal>num_nulls(1, NULL, 2)</literal>
+        <returnvalue>1</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  </sect1>
diff --git a/doc/src/sgml/func/func-comparisons.sgml b/doc/src/sgml/func/func-comparisons.sgml
new file mode 100644
index 0000000000000..6a6e0bd401920
--- /dev/null
+++ b/doc/src/sgml/func/func-comparisons.sgml
@@ -0,0 +1,336 @@
+ <sect1 id="functions-comparisons">
+  <title>Row and Array Comparisons</title>
+
+  <indexterm>
+   <primary>IN</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>NOT IN</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>ANY</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>ALL</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>SOME</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>composite type</primary>
+   <secondary>comparison</secondary>
+  </indexterm>
+
+  <indexterm>
+   <primary>row-wise comparison</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>comparison</primary>
+   <secondary>composite type</secondary>
+  </indexterm>
+
+  <indexterm>
+   <primary>comparison</primary>
+   <secondary>row constructor</secondary>
+  </indexterm>
+
+  <indexterm>
+   <primary>IS DISTINCT FROM</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>IS NOT DISTINCT FROM</primary>
+  </indexterm>
+
+  <para>
+   This section describes several specialized constructs for making
+   multiple comparisons between groups of values.  These forms are
+   syntactically related to the subquery forms of the previous section,
+   but do not involve subqueries.
+   The forms involving array subexpressions are
+   <productname>PostgreSQL</productname> extensions; the rest are
+   <acronym>SQL</acronym>-compliant.
+   All of the expression forms documented in this section return
+   Boolean (true/false) results.
+  </para>
+
+  <sect2 id="functions-comparisons-in-scalar">
+   <title><literal>IN</literal></title>
+
+<synopsis>
+<replaceable>expression</replaceable> IN (<replaceable>value</replaceable> <optional>, ...</optional>)
+</synopsis>
+
+  <para>
+   The right-hand side is a parenthesized list
+   of expressions.  The result is <quote>true</quote> if the left-hand expression's
+   result is equal to any of the right-hand expressions.  This is a shorthand
+   notation for
+
+<synopsis>
+<replaceable>expression</replaceable> = <replaceable>value1</replaceable>
+OR
+<replaceable>expression</replaceable> = <replaceable>value2</replaceable>
+OR
+...
+</synopsis>
+  </para>
+
+  <para>
+   Note that if the left-hand expression yields null, or if there are
+   no equal right-hand values and at least one right-hand expression yields
+   null, the result of the <token>IN</token> construct will be null, not false.
+   This is in accordance with SQL's normal rules for Boolean combinations
+   of null values.
+  </para>
+  </sect2>
+
+  <sect2 id="functions-comparisons-not-in">
+   <title><literal>NOT IN</literal></title>
+
+<synopsis>
+<replaceable>expression</replaceable> NOT IN (<replaceable>value</replaceable> <optional>, ...</optional>)
+</synopsis>
+
+  <para>
+   The right-hand side is a parenthesized list
+   of expressions.  The result is <quote>true</quote> if the left-hand expression's
+   result is unequal to all of the right-hand expressions.  This is a shorthand
+   notation for
+
+<synopsis>
+<replaceable>expression</replaceable> &lt;&gt; <replaceable>value1</replaceable>
+AND
+<replaceable>expression</replaceable> &lt;&gt; <replaceable>value2</replaceable>
+AND
+...
+</synopsis>
+  </para>
+
+  <para>
+   Note that if the left-hand expression yields null, or if there are
+   no equal right-hand values and at least one right-hand expression yields
+   null, the result of the <token>NOT IN</token> construct will be null, not true
+   as one might naively expect.
+   This is in accordance with SQL's normal rules for Boolean combinations
+   of null values.
+  </para>
+
+  <tip>
+  <para>
+   <literal>x NOT IN y</literal> is equivalent to <literal>NOT (x IN y)</literal> in all
+   cases.  However, null values are much more likely to trip up the novice when
+   working with <token>NOT IN</token> than when working with <token>IN</token>.
+   It is best to express your condition positively if possible.
+  </para>
+  </tip>
+  </sect2>
+
+  <sect2 id="functions-comparisons-any-some">
+   <title><literal>ANY</literal>/<literal>SOME</literal> (array)</title>
+
+<synopsis>
+<replaceable>expression</replaceable> <replaceable>operator</replaceable> ANY (<replaceable>array expression</replaceable>)
+<replaceable>expression</replaceable> <replaceable>operator</replaceable> SOME (<replaceable>array expression</replaceable>)
+</synopsis>
+
+  <para>
+   The right-hand side is a parenthesized expression, which must yield an
+   array value.
+   The left-hand expression
+   is evaluated and compared to each element of the array using the
+   given <replaceable>operator</replaceable>, which must yield a Boolean
+   result.
+   The result of <token>ANY</token> is <quote>true</quote> if any true result is obtained.
+   The result is <quote>false</quote> if no true result is found (including the
+   case where the array has zero elements).
+  </para>
+
+  <para>
+   If the array expression yields a null array, the result of
+   <token>ANY</token> will be null.  If the left-hand expression yields null,
+   the result of <token>ANY</token> is ordinarily null (though a non-strict
+   comparison operator could possibly yield a different result).
+   Also, if the right-hand array contains any null elements and no true
+   comparison result is obtained, the result of <token>ANY</token>
+   will be null, not false (again, assuming a strict comparison operator).
+   This is in accordance with SQL's normal rules for Boolean combinations
+   of null values.
+  </para>
+
+  <para>
+   <token>SOME</token> is a synonym for <token>ANY</token>.
+  </para>
+  </sect2>
+
+  <sect2 id="functions-comparisons-all">
+   <title><literal>ALL</literal> (array)</title>
+
+<synopsis>
+<replaceable>expression</replaceable> <replaceable>operator</replaceable> ALL (<replaceable>array expression</replaceable>)
+</synopsis>
+
+  <para>
+   The right-hand side is a parenthesized expression, which must yield an
+   array value.
+   The left-hand expression
+   is evaluated and compared to each element of the array using the
+   given <replaceable>operator</replaceable>, which must yield a Boolean
+   result.
+   The result of <token>ALL</token> is <quote>true</quote> if all comparisons yield true
+   (including the case where the array has zero elements).
+   The result is <quote>false</quote> if any false result is found.
+  </para>
+
+  <para>
+   If the array expression yields a null array, the result of
+   <token>ALL</token> will be null.  If the left-hand expression yields null,
+   the result of <token>ALL</token> is ordinarily null (though a non-strict
+   comparison operator could possibly yield a different result).
+   Also, if the right-hand array contains any null elements and no false
+   comparison result is obtained, the result of <token>ALL</token>
+   will be null, not true (again, assuming a strict comparison operator).
+   This is in accordance with SQL's normal rules for Boolean combinations
+   of null values.
+  </para>
+  </sect2>
+
+  <sect2 id="row-wise-comparison">
+   <title>Row Constructor Comparison</title>
+
+<synopsis>
+<replaceable>row_constructor</replaceable> <replaceable>operator</replaceable> <replaceable>row_constructor</replaceable>
+</synopsis>
+
+  <para>
+   Each side is a row constructor,
+   as described in <xref linkend="sql-syntax-row-constructors"/>.
+   The two row constructors must have the same number of fields.
+   The given <replaceable>operator</replaceable> is applied to each pair
+   of corresponding fields.  (Since the fields could be of different
+   types, this means that a different specific operator could be selected
+   for each pair.)
+   All the selected operators must be members of some B-tree operator
+   class, or be the negator of an <literal>=</literal> member of a B-tree
+   operator class, meaning that row constructor comparison is only
+   possible when the <replaceable>operator</replaceable> is
+   <literal>=</literal>,
+   <literal>&lt;&gt;</literal>,
+   <literal>&lt;</literal>,
+   <literal>&lt;=</literal>,
+   <literal>&gt;</literal>, or
+   <literal>&gt;=</literal>,
+   or has semantics similar to one of these.
+  </para>
+
+  <para>
+   The <literal>=</literal> and <literal>&lt;&gt;</literal> cases work slightly differently
+   from the others.  Two rows are considered
+   equal if all their corresponding members are non-null and equal; the rows
+   are unequal if any corresponding members are non-null and unequal;
+   otherwise the result of the row comparison is unknown (null).
+  </para>
+
+  <para>
+   For the <literal>&lt;</literal>, <literal>&lt;=</literal>, <literal>&gt;</literal> and
+   <literal>&gt;=</literal> cases, the row elements are compared left-to-right,
+   stopping as soon as an unequal or null pair of elements is found.
+   If either of this pair of elements is null, the result of the
+   row comparison is unknown (null); otherwise comparison of this pair
+   of elements determines the result.  For example,
+   <literal>ROW(1,2,NULL) &lt; ROW(1,3,0)</literal>
+   yields true, not null, because the third pair of elements are not
+   considered.
+  </para>
+
+<synopsis>
+<replaceable>row_constructor</replaceable> IS DISTINCT FROM <replaceable>row_constructor</replaceable>
+</synopsis>
+
+  <para>
+   This construct is similar to a <literal>&lt;&gt;</literal> row comparison,
+   but it does not yield null for null inputs.  Instead, any null value is
+   considered unequal to (distinct from) any non-null value, and any two
+   nulls are considered equal (not distinct).  Thus the result will
+   either be true or false, never null.
+  </para>
+
+<synopsis>
+<replaceable>row_constructor</replaceable> IS NOT DISTINCT FROM <replaceable>row_constructor</replaceable>
+</synopsis>
+
+  <para>
+   This construct is similar to a <literal>=</literal> row comparison,
+   but it does not yield null for null inputs.  Instead, any null value is
+   considered unequal to (distinct from) any non-null value, and any two
+   nulls are considered equal (not distinct).  Thus the result will always
+   be either true or false, never null.
+  </para>
+
+  </sect2>
+
+  <sect2 id="composite-type-comparison">
+   <title>Composite Type Comparison</title>
+
+<synopsis>
+<replaceable>record</replaceable> <replaceable>operator</replaceable> <replaceable>record</replaceable>
+</synopsis>
+
+  <para>
+   The SQL specification requires row-wise comparison to return NULL if the
+   result depends on comparing two NULL values or a NULL and a non-NULL.
+   <productname>PostgreSQL</productname> does this only when comparing the
+   results of two row constructors (as in
+   <xref linkend="row-wise-comparison"/>) or comparing a row constructor
+   to the output of a subquery (as in <xref linkend="functions-subquery"/>).
+   In other contexts where two composite-type values are compared, two
+   NULL field values are considered equal, and a NULL is considered larger
+   than a non-NULL.  This is necessary in order to have consistent sorting
+   and indexing behavior for composite types.
+  </para>
+
+  <para>
+   Each side is evaluated and they are compared row-wise.  Composite type
+   comparisons are allowed when the <replaceable>operator</replaceable> is
+   <literal>=</literal>,
+   <literal>&lt;&gt;</literal>,
+   <literal>&lt;</literal>,
+   <literal>&lt;=</literal>,
+   <literal>&gt;</literal> or
+   <literal>&gt;=</literal>,
+   or has semantics similar to one of these.  (To be specific, an operator
+   can be a row comparison operator if it is a member of a B-tree operator
+   class, or is the negator of the <literal>=</literal> member of a B-tree operator
+   class.)  The default behavior of the above operators is the same as for
+   <literal>IS [ NOT ] DISTINCT FROM</literal> for row constructors (see
+   <xref linkend="row-wise-comparison"/>).
+  </para>
+
+  <para>
+   To support matching of rows which include elements without a default
+   B-tree operator class, the following operators are defined for composite
+   type comparison:
+   <literal>*=</literal>,
+   <literal>*&lt;&gt;</literal>,
+   <literal>*&lt;</literal>,
+   <literal>*&lt;=</literal>,
+   <literal>*&gt;</literal>, and
+   <literal>*&gt;=</literal>.
+   These operators compare the internal binary representation of the two
+   rows.  Two rows might have a different binary representation even
+   though comparisons of the two rows with the equality operator is true.
+   The ordering of rows under these comparison operators is deterministic
+   but not otherwise meaningful.  These operators are used internally
+   for materialized views and might be useful for other specialized
+   purposes such as replication and B-Tree deduplication (see <xref
+   linkend="btree-deduplication"/>).  They are not intended to be
+   generally useful for writing queries, though.
+  </para>
+  </sect2>
+ </sect1>
diff --git a/doc/src/sgml/func/func-conditional.sgml b/doc/src/sgml/func/func-conditional.sgml
new file mode 100644
index 0000000000000..7ca53dbf1ab03
--- /dev/null
+++ b/doc/src/sgml/func/func-conditional.sgml
@@ -0,0 +1,283 @@
+ <sect1 id="functions-conditional">
+  <title>Conditional Expressions</title>
+
+  <indexterm>
+   <primary>CASE</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>conditional expression</primary>
+  </indexterm>
+
+  <para>
+   This section describes the <acronym>SQL</acronym>-compliant conditional expressions
+   available in <productname>PostgreSQL</productname>.
+  </para>
+
+  <tip>
+   <para>
+    If your needs go beyond the capabilities of these conditional
+    expressions, you might want to consider writing a server-side function
+    in a more expressive programming language.
+   </para>
+  </tip>
+
+   <note>
+    <para>
+     Although <token>COALESCE</token>, <token>GREATEST</token>, and
+     <token>LEAST</token> are syntactically similar to functions, they are
+     not ordinary functions, and thus cannot be used with explicit
+     <token>VARIADIC</token> array arguments.
+    </para>
+   </note>
+
+  <sect2 id="functions-case">
+   <title><literal>CASE</literal></title>
+
+  <para>
+   The <acronym>SQL</acronym> <token>CASE</token> expression is a
+   generic conditional expression, similar to if/else statements in
+   other programming languages:
+
+<synopsis>
+CASE WHEN <replaceable>condition</replaceable> THEN <replaceable>result</replaceable>
+     <optional>WHEN ...</optional>
+     <optional>ELSE <replaceable>result</replaceable></optional>
+END
+</synopsis>
+
+   <token>CASE</token> clauses can be used wherever
+   an expression is valid.  Each <replaceable>condition</replaceable> is an
+   expression that returns a <type>boolean</type> result.  If the condition's
+   result is true, the value of the <token>CASE</token> expression is the
+   <replaceable>result</replaceable> that follows the condition, and the
+   remainder of the <token>CASE</token> expression is not processed.  If the
+   condition's result is not true, any subsequent <token>WHEN</token> clauses
+   are examined in the same manner.  If no <token>WHEN</token>
+   <replaceable>condition</replaceable> yields true, the value of the
+   <token>CASE</token> expression is the <replaceable>result</replaceable> of the
+   <token>ELSE</token> clause.  If the <token>ELSE</token> clause is
+   omitted and no condition is true, the result is null.
+  </para>
+
+   <para>
+    An example:
+<screen>
+SELECT * FROM test;
+
+ a
+---
+ 1
+ 2
+ 3
+
+
+SELECT a,
+       CASE WHEN a=1 THEN 'one'
+            WHEN a=2 THEN 'two'
+            ELSE 'other'
+       END
+    FROM test;
+
+ a | case
+---+-------
+ 1 | one
+ 2 | two
+ 3 | other
+</screen>
+   </para>
+
+  <para>
+   The data types of all the <replaceable>result</replaceable>
+   expressions must be convertible to a single output type.
+   See <xref linkend="typeconv-union-case"/> for more details.
+  </para>
+
+  <para>
+   There is a <quote>simple</quote> form of <token>CASE</token> expression
+   that is a variant of the general form above:
+
+<synopsis>
+CASE <replaceable>expression</replaceable>
+    WHEN <replaceable>value</replaceable> THEN <replaceable>result</replaceable>
+    <optional>WHEN ...</optional>
+    <optional>ELSE <replaceable>result</replaceable></optional>
+END
+</synopsis>
+
+   The first
+   <replaceable>expression</replaceable> is computed, then compared to
+   each of the <replaceable>value</replaceable> expressions in the
+   <token>WHEN</token> clauses until one is found that is equal to it.  If
+   no match is found, the <replaceable>result</replaceable> of the
+   <token>ELSE</token> clause (or a null value) is returned.  This is similar
+   to the <function>switch</function> statement in C.
+  </para>
+
+   <para>
+    The example above can be written using the simple
+    <token>CASE</token> syntax:
+<screen>
+SELECT a,
+       CASE a WHEN 1 THEN 'one'
+              WHEN 2 THEN 'two'
+              ELSE 'other'
+       END
+    FROM test;
+
+ a | case
+---+-------
+ 1 | one
+ 2 | two
+ 3 | other
+</screen>
+   </para>
+
+   <para>
+    A <token>CASE</token> expression does not evaluate any subexpressions
+    that are not needed to determine the result.  For example, this is a
+    possible way of avoiding a division-by-zero failure:
+<programlisting>
+SELECT ... WHERE CASE WHEN x &lt;&gt; 0 THEN y/x &gt; 1.5 ELSE false END;
+</programlisting>
+   </para>
+
+   <note>
+    <para>
+     As described in <xref linkend="syntax-express-eval"/>, there are various
+     situations in which subexpressions of an expression are evaluated at
+     different times, so that the principle that <quote><token>CASE</token>
+     evaluates only necessary subexpressions</quote> is not ironclad.  For
+     example a constant <literal>1/0</literal> subexpression will usually result in
+     a division-by-zero failure at planning time, even if it's within
+     a <token>CASE</token> arm that would never be entered at run time.
+    </para>
+   </note>
+  </sect2>
+
+  <sect2 id="functions-coalesce-nvl-ifnull">
+   <title><literal>COALESCE</literal></title>
+
+  <indexterm>
+   <primary>COALESCE</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>NVL</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>IFNULL</primary>
+  </indexterm>
+
+<synopsis>
+<function>COALESCE</function>(<replaceable>value</replaceable> <optional>, ...</optional>)
+</synopsis>
+
+  <para>
+   The <function>COALESCE</function> function returns the first of its
+   arguments that is not null.  Null is returned only if all arguments
+   are null.  It is often used to substitute a default value for
+   null values when data is retrieved for display, for example:
+<programlisting>
+SELECT COALESCE(description, short_description, '(none)') ...
+</programlisting>
+   This returns <varname>description</varname> if it is not null, otherwise
+   <varname>short_description</varname> if it is not null, otherwise <literal>(none)</literal>.
+  </para>
+
+   <para>
+    The arguments must all be convertible to a common data type, which
+    will be the type of the result (see
+    <xref linkend="typeconv-union-case"/> for details).
+   </para>
+
+   <para>
+    Like a <token>CASE</token> expression, <function>COALESCE</function> only
+    evaluates the arguments that are needed to determine the result;
+    that is, arguments to the right of the first non-null argument are
+    not evaluated.  This SQL-standard function provides capabilities similar
+    to <function>NVL</function> and <function>IFNULL</function>, which are used in some other
+    database systems.
+   </para>
+  </sect2>
+
+  <sect2 id="functions-nullif">
+   <title><literal>NULLIF</literal></title>
+
+  <indexterm>
+   <primary>NULLIF</primary>
+  </indexterm>
+
+<synopsis>
+<function>NULLIF</function>(<replaceable>value1</replaceable>, <replaceable>value2</replaceable>)
+</synopsis>
+
+  <para>
+   The <function>NULLIF</function> function returns a null value if
+   <replaceable>value1</replaceable> equals <replaceable>value2</replaceable>;
+   otherwise it returns <replaceable>value1</replaceable>.
+   This can be used to perform the inverse operation of the
+   <function>COALESCE</function> example given above:
+<programlisting>
+SELECT NULLIF(value, '(none)') ...
+</programlisting>
+   In this example, if <literal>value</literal> is <literal>(none)</literal>,
+   null is returned, otherwise the value of <literal>value</literal>
+   is returned.
+  </para>
+
+  <para>
+   The two arguments must be of comparable types.
+   To be specific, they are compared exactly as if you had
+   written <literal><replaceable>value1</replaceable>
+   = <replaceable>value2</replaceable></literal>, so there must be a
+   suitable <literal>=</literal> operator available.
+  </para>
+
+  <para>
+   The result has the same type as the first argument &mdash; but there is
+   a subtlety.  What is actually returned is the first argument of the
+   implied <literal>=</literal> operator, and in some cases that will have
+   been promoted to match the second argument's type.  For
+   example, <literal>NULLIF(1, 2.2)</literal> yields <type>numeric</type>,
+   because there is no <type>integer</type> <literal>=</literal>
+   <type>numeric</type> operator,
+   only <type>numeric</type> <literal>=</literal> <type>numeric</type>.
+  </para>
+
+  </sect2>
+
+  <sect2 id="functions-greatest-least">
+   <title><literal>GREATEST</literal> and <literal>LEAST</literal></title>
+
+  <indexterm>
+   <primary>GREATEST</primary>
+  </indexterm>
+  <indexterm>
+   <primary>LEAST</primary>
+  </indexterm>
+
+<synopsis>
+<function>GREATEST</function>(<replaceable>value</replaceable> <optional>, ...</optional>)
+</synopsis>
+<synopsis>
+<function>LEAST</function>(<replaceable>value</replaceable> <optional>, ...</optional>)
+</synopsis>
+
+   <para>
+    The <function>GREATEST</function> and <function>LEAST</function> functions select the
+    largest or smallest value from a list of any number of expressions.
+    The expressions must all be convertible to a common data type, which
+    will be the type of the result
+    (see <xref linkend="typeconv-union-case"/> for details).
+   </para>
+
+   <para>
+    NULL values in the argument list are ignored.  The result will be NULL
+    only if all the expressions evaluate to NULL.  (This is a deviation from
+    the SQL standard.  According to the standard, the return value is NULL if
+    any argument is NULL.  Some other databases behave this way.)
+   </para>
+  </sect2>
+ </sect1>
diff --git a/doc/src/sgml/func/func-datetime.sgml b/doc/src/sgml/func/func-datetime.sgml
new file mode 100644
index 0000000000000..482fe45f42ebc
--- /dev/null
+++ b/doc/src/sgml/func/func-datetime.sgml
@@ -0,0 +1,2200 @@
+  <sect1 id="functions-datetime">
+   <title>Date/Time Functions and Operators</title>
+
+  <para>
+   <xref linkend="functions-datetime-table"/> shows the available
+   functions for date/time value processing, with details appearing in
+   the following subsections.  <xref
+   linkend="operators-datetime-table"/> illustrates the behaviors of
+   the basic arithmetic operators (<literal>+</literal>,
+   <literal>*</literal>, etc.).  For formatting functions, refer to
+   <xref linkend="functions-formatting"/>.  You should be familiar with
+   the background information on date/time data types from <xref
+   linkend="datatype-datetime"/>.
+  </para>
+
+  <para>
+   In addition, the usual comparison operators shown in
+   <xref linkend="functions-comparison-op-table"/> are available for the
+   date/time types.  Dates and timestamps (with or without time zone) are
+   all comparable, while times (with or without time zone) and intervals
+   can only be compared to other values of the same data type.  When
+   comparing a timestamp without time zone to a timestamp with time zone,
+   the former value is assumed to be given in the time zone specified by
+   the <xref linkend="guc-timezone"/> configuration parameter, and is
+   rotated to UTC for comparison to the latter value (which is already
+   in UTC internally).  Similarly, a date value is assumed to represent
+   midnight in the <varname>TimeZone</varname> zone when comparing it
+   to a timestamp.
+  </para>
+
+  <para>
+   All the functions and operators described below that take <type>time</type> or <type>timestamp</type>
+   inputs actually come in two variants: one that takes <type>time with time zone</type> or <type>timestamp
+   with time zone</type>, and one that takes <type>time without time zone</type> or <type>timestamp without time zone</type>.
+   For brevity, these variants are not shown separately.  Also, the
+   <literal>+</literal> and <literal>*</literal> operators come in commutative pairs (for
+   example both <type>date</type> <literal>+</literal> <type>integer</type>
+   and <type>integer</type> <literal>+</literal> <type>date</type>); we show
+   only one of each such pair.
+  </para>
+
+    <table id="operators-datetime-table">
+     <title>Date/Time Operators</title>
+
+     <tgroup cols="1">
+      <thead>
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         Operator
+        </para>
+        <para>
+         Description
+        </para>
+        <para>
+         Example(s)
+        </para></entry>
+       </row>
+      </thead>
+
+      <tbody>
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>date</type> <literal>+</literal> <type>integer</type>
+         <returnvalue>date</returnvalue>
+        </para>
+        <para>
+         Add a number of days to a date
+        </para>
+        <para>
+         <literal>date '2001-09-28' + 7</literal>
+         <returnvalue>2001-10-05</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>date</type> <literal>+</literal> <type>interval</type>
+         <returnvalue>timestamp</returnvalue>
+        </para>
+        <para>
+         Add an interval to a date
+        </para>
+        <para>
+         <literal>date '2001-09-28' + interval '1 hour'</literal>
+         <returnvalue>2001-09-28 01:00:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>date</type> <literal>+</literal> <type>time</type>
+         <returnvalue>timestamp</returnvalue>
+        </para>
+        <para>
+         Add a time-of-day to a date
+        </para>
+        <para>
+         <literal>date '2001-09-28' + time '03:00'</literal>
+         <returnvalue>2001-09-28 03:00:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>interval</type> <literal>+</literal> <type>interval</type>
+         <returnvalue>interval</returnvalue>
+        </para>
+        <para>
+         Add intervals
+        </para>
+        <para>
+         <literal>interval '1 day' + interval '1 hour'</literal>
+         <returnvalue>1 day 01:00:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>timestamp</type> <literal>+</literal> <type>interval</type>
+         <returnvalue>timestamp</returnvalue>
+        </para>
+        <para>
+         Add an interval to a timestamp
+        </para>
+        <para>
+         <literal>timestamp '2001-09-28 01:00' + interval '23 hours'</literal>
+         <returnvalue>2001-09-29 00:00:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>time</type> <literal>+</literal> <type>interval</type>
+         <returnvalue>time</returnvalue>
+        </para>
+        <para>
+         Add an interval to a time
+        </para>
+        <para>
+         <literal>time '01:00' + interval '3 hours'</literal>
+         <returnvalue>04:00:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <literal>-</literal> <type>interval</type>
+         <returnvalue>interval</returnvalue>
+        </para>
+        <para>
+         Negate an interval
+        </para>
+        <para>
+         <literal>- interval '23 hours'</literal>
+         <returnvalue>-23:00:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>date</type> <literal>-</literal> <type>date</type>
+         <returnvalue>integer</returnvalue>
+        </para>
+        <para>
+         Subtract dates, producing the number of days elapsed
+        </para>
+        <para>
+         <literal>date '2001-10-01' - date '2001-09-28'</literal>
+         <returnvalue>3</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>date</type> <literal>-</literal> <type>integer</type>
+         <returnvalue>date</returnvalue>
+        </para>
+        <para>
+         Subtract a number of days from a date
+        </para>
+        <para>
+         <literal>date '2001-10-01' - 7</literal>
+         <returnvalue>2001-09-24</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>date</type> <literal>-</literal> <type>interval</type>
+         <returnvalue>timestamp</returnvalue>
+        </para>
+        <para>
+         Subtract an interval from a date
+        </para>
+        <para>
+         <literal>date '2001-09-28' - interval '1 hour'</literal>
+         <returnvalue>2001-09-27 23:00:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>time</type> <literal>-</literal> <type>time</type>
+         <returnvalue>interval</returnvalue>
+        </para>
+        <para>
+         Subtract times
+        </para>
+        <para>
+         <literal>time '05:00' - time '03:00'</literal>
+         <returnvalue>02:00:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>time</type> <literal>-</literal> <type>interval</type>
+         <returnvalue>time</returnvalue>
+        </para>
+        <para>
+         Subtract an interval from a time
+        </para>
+        <para>
+         <literal>time '05:00' - interval '2 hours'</literal>
+         <returnvalue>03:00:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>timestamp</type> <literal>-</literal> <type>interval</type>
+         <returnvalue>timestamp</returnvalue>
+        </para>
+        <para>
+         Subtract an interval from a timestamp
+        </para>
+        <para>
+         <literal>timestamp '2001-09-28 23:00' - interval '23 hours'</literal>
+         <returnvalue>2001-09-28 00:00:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>interval</type> <literal>-</literal> <type>interval</type>
+         <returnvalue>interval</returnvalue>
+        </para>
+        <para>
+         Subtract intervals
+        </para>
+        <para>
+         <literal>interval '1 day' - interval '1 hour'</literal>
+         <returnvalue>1 day -01:00:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>timestamp</type> <literal>-</literal> <type>timestamp</type>
+         <returnvalue>interval</returnvalue>
+        </para>
+        <para>
+         Subtract timestamps (converting 24-hour intervals into days,
+         similarly to <link
+         linkend="function-justify-hours"><function>justify_hours()</function></link>)
+        </para>
+        <para>
+         <literal>timestamp '2001-09-29 03:00' - timestamp '2001-07-27 12:00'</literal>
+         <returnvalue>63 days 15:00:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>interval</type> <literal>*</literal> <type>double precision</type>
+         <returnvalue>interval</returnvalue>
+        </para>
+        <para>
+         Multiply an interval by a scalar
+        </para>
+        <para>
+         <literal>interval '1 second' * 900</literal>
+         <returnvalue>00:15:00</returnvalue>
+        </para>
+        <para>
+         <literal>interval '1 day' * 21</literal>
+         <returnvalue>21 days</returnvalue>
+        </para>
+        <para>
+         <literal>interval '1 hour' * 3.5</literal>
+         <returnvalue>03:30:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>interval</type> <literal>/</literal> <type>double precision</type>
+         <returnvalue>interval</returnvalue>
+        </para>
+        <para>
+         Divide an interval by a scalar
+        </para>
+        <para>
+         <literal>interval '1 hour' / 1.5</literal>
+         <returnvalue>00:40:00</returnvalue>
+        </para></entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+    <table id="functions-datetime-table">
+     <title>Date/Time Functions</title>
+     <tgroup cols="1">
+      <thead>
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         Function
+        </para>
+        <para>
+         Description
+        </para>
+        <para>
+         Example(s)
+        </para></entry>
+       </row>
+      </thead>
+
+      <tbody>
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>age</primary>
+         </indexterm>
+         <function>age</function> ( <type>timestamp</type>, <type>timestamp</type> )
+         <returnvalue>interval</returnvalue>
+        </para>
+        <para>
+         Subtract arguments, producing a <quote>symbolic</quote> result that
+         uses years and months, rather than just days
+        </para>
+        <para>
+         <literal>age(timestamp '2001-04-10', timestamp '1957-06-13')</literal>
+         <returnvalue>43 years 9 mons 27 days</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <function>age</function> ( <type>timestamp</type> )
+         <returnvalue>interval</returnvalue>
+        </para>
+        <para>
+         Subtract argument from <function>current_date</function> (at midnight)
+        </para>
+        <para>
+         <literal>age(timestamp '1957-06-13')</literal>
+         <returnvalue>62 years 6 mons 10 days</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>clock_timestamp</primary>
+         </indexterm>
+         <function>clock_timestamp</function> ( )
+         <returnvalue>timestamp with time zone</returnvalue>
+        </para>
+        <para>
+         Current date and time (changes during statement execution);
+         see <xref linkend="functions-datetime-current"/>
+        </para>
+        <para>
+         <literal>clock_timestamp()</literal>
+         <returnvalue>2019-12-23 14:39:53.662522-05</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>current_date</primary>
+         </indexterm>
+         <function>current_date</function>
+         <returnvalue>date</returnvalue>
+        </para>
+        <para>
+         Current date; see <xref linkend="functions-datetime-current"/>
+        </para>
+        <para>
+         <literal>current_date</literal>
+         <returnvalue>2019-12-23</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>current_time</primary>
+         </indexterm>
+         <function>current_time</function>
+         <returnvalue>time with time zone</returnvalue>
+        </para>
+        <para>
+         Current time of day; see <xref linkend="functions-datetime-current"/>
+        </para>
+        <para>
+         <literal>current_time</literal>
+         <returnvalue>14:39:53.662522-05</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <function>current_time</function> ( <type>integer</type> )
+         <returnvalue>time with time zone</returnvalue>
+        </para>
+        <para>
+         Current time of day, with limited precision;
+         see <xref linkend="functions-datetime-current"/>
+        </para>
+        <para>
+         <literal>current_time(2)</literal>
+         <returnvalue>14:39:53.66-05</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>current_timestamp</primary>
+         </indexterm>
+         <function>current_timestamp</function>
+         <returnvalue>timestamp with time zone</returnvalue>
+        </para>
+        <para>
+         Current date and time (start of current transaction);
+         see <xref linkend="functions-datetime-current"/>
+        </para>
+        <para>
+         <literal>current_timestamp</literal>
+         <returnvalue>2019-12-23 14:39:53.662522-05</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <function>current_timestamp</function> ( <type>integer</type> )
+         <returnvalue>timestamp with time zone</returnvalue>
+        </para>
+        <para>
+         Current date and time (start of current transaction), with limited precision;
+         see <xref linkend="functions-datetime-current"/>
+        </para>
+        <para>
+         <literal>current_timestamp(0)</literal>
+         <returnvalue>2019-12-23 14:39:53-05</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>date_add</primary>
+         </indexterm>
+         <function>date_add</function> ( <type>timestamp with time zone</type>, <type>interval</type> <optional>, <type>text</type> </optional> )
+         <returnvalue>timestamp with time zone</returnvalue>
+        </para>
+        <para>
+         Add an <type>interval</type> to a <type>timestamp with time
+         zone</type>, computing times of day and daylight-savings adjustments
+         according to the time zone named by the third argument, or the
+         current <xref linkend="guc-timezone"/> setting if that is omitted.
+         The form with two arguments is equivalent to the <type>timestamp with
+         time zone</type> <literal>+</literal> <type>interval</type> operator.
+        </para>
+        <para>
+         <literal>date_add('2021-10-31 00:00:00+02'::timestamptz, '1 day'::interval, 'Europe/Warsaw')</literal>
+         <returnvalue>2021-10-31 23:00:00+00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <function>date_bin</function> ( <type>interval</type>, <type>timestamp</type>, <type>timestamp</type> )
+         <returnvalue>timestamp</returnvalue>
+        </para>
+        <para>
+         Bin input into specified interval aligned with specified origin; see <xref linkend="functions-datetime-bin"/>
+        </para>
+        <para>
+         <literal>date_bin('15 minutes', timestamp '2001-02-16 20:38:40', timestamp '2001-02-16 20:05:00')</literal>
+         <returnvalue>2001-02-16 20:35:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>date_part</primary>
+         </indexterm>
+         <function>date_part</function> ( <type>text</type>, <type>timestamp</type> )
+         <returnvalue>double precision</returnvalue>
+        </para>
+        <para>
+         Get timestamp subfield (equivalent to <function>extract</function>);
+         see <xref linkend="functions-datetime-extract"/>
+        </para>
+        <para>
+         <literal>date_part('hour', timestamp '2001-02-16 20:38:40')</literal>
+         <returnvalue>20</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <function>date_part</function> ( <type>text</type>, <type>interval</type> )
+         <returnvalue>double precision</returnvalue>
+        </para>
+        <para>
+         Get interval subfield (equivalent to <function>extract</function>);
+         see <xref linkend="functions-datetime-extract"/>
+        </para>
+        <para>
+         <literal>date_part('month', interval '2 years 3 months')</literal>
+         <returnvalue>3</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>date_subtract</primary>
+         </indexterm>
+         <function>date_subtract</function> ( <type>timestamp with time zone</type>, <type>interval</type> <optional>, <type>text</type> </optional> )
+         <returnvalue>timestamp with time zone</returnvalue>
+        </para>
+        <para>
+         Subtract an <type>interval</type> from a <type>timestamp with time
+         zone</type>, computing times of day and daylight-savings adjustments
+         according to the time zone named by the third argument, or the
+         current <xref linkend="guc-timezone"/> setting if that is omitted.
+         The form with two arguments is equivalent to the <type>timestamp with
+         time zone</type> <literal>-</literal> <type>interval</type> operator.
+        </para>
+        <para>
+         <literal>date_subtract('2021-11-01 00:00:00+01'::timestamptz, '1 day'::interval, 'Europe/Warsaw')</literal>
+         <returnvalue>2021-10-30 22:00:00+00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>date_trunc</primary>
+         </indexterm>
+         <function>date_trunc</function> ( <type>text</type>, <type>timestamp</type> )
+         <returnvalue>timestamp</returnvalue>
+        </para>
+        <para>
+         Truncate to specified precision; see <xref linkend="functions-datetime-trunc"/>
+        </para>
+        <para>
+         <literal>date_trunc('hour', timestamp '2001-02-16 20:38:40')</literal>
+         <returnvalue>2001-02-16 20:00:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <function>date_trunc</function> ( <type>text</type>, <type>timestamp with time zone</type>, <type>text</type> )
+         <returnvalue>timestamp with time zone</returnvalue>
+        </para>
+        <para>
+         Truncate to specified precision in the specified time zone; see
+         <xref linkend="functions-datetime-trunc"/>
+        </para>
+        <para>
+         <literal>date_trunc('day', timestamptz '2001-02-16 20:38:40+00', 'Australia/Sydney')</literal>
+         <returnvalue>2001-02-16 13:00:00+00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <function>date_trunc</function> ( <type>text</type>, <type>interval</type> )
+         <returnvalue>interval</returnvalue>
+        </para>
+        <para>
+         Truncate to specified precision; see
+         <xref linkend="functions-datetime-trunc"/>
+        </para>
+        <para>
+         <literal>date_trunc('hour', interval '2 days 3 hours 40 minutes')</literal>
+         <returnvalue>2 days 03:00:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>extract</primary>
+         </indexterm>
+         <function>extract</function> ( <parameter>field</parameter> <literal>from</literal> <type>timestamp</type> )
+         <returnvalue>numeric</returnvalue>
+        </para>
+        <para>
+         Get timestamp subfield; see <xref linkend="functions-datetime-extract"/>
+        </para>
+        <para>
+         <literal>extract(hour from timestamp '2001-02-16 20:38:40')</literal>
+         <returnvalue>20</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <function>extract</function> ( <parameter>field</parameter> <literal>from</literal> <type>interval</type> )
+         <returnvalue>numeric</returnvalue>
+        </para>
+        <para>
+         Get interval subfield; see <xref linkend="functions-datetime-extract"/>
+        </para>
+        <para>
+         <literal>extract(month from interval '2 years 3 months')</literal>
+         <returnvalue>3</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>isfinite</primary>
+         </indexterm>
+         <function>isfinite</function> ( <type>date</type> )
+         <returnvalue>boolean</returnvalue>
+        </para>
+        <para>
+         Test for finite date (not +/-infinity)
+        </para>
+        <para>
+         <literal>isfinite(date '2001-02-16')</literal>
+         <returnvalue>true</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <function>isfinite</function> ( <type>timestamp</type> )
+         <returnvalue>boolean</returnvalue>
+        </para>
+        <para>
+         Test for finite timestamp (not +/-infinity)
+        </para>
+        <para>
+         <literal>isfinite(timestamp 'infinity')</literal>
+         <returnvalue>false</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <function>isfinite</function> ( <type>interval</type> )
+         <returnvalue>boolean</returnvalue>
+        </para>
+        <para>
+         Test for finite interval (not +/-infinity)
+        </para>
+        <para>
+         <literal>isfinite(interval '4 hours')</literal>
+         <returnvalue>true</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm id="function-justify-days">
+          <primary>justify_days</primary>
+         </indexterm>
+         <function>justify_days</function> ( <type>interval</type> )
+         <returnvalue>interval</returnvalue>
+        </para>
+        <para>
+         Adjust interval, converting 30-day time periods to months
+        </para>
+        <para>
+         <literal>justify_days(interval '1 year 65 days')</literal>
+         <returnvalue>1 year 2 mons 5 days</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm id="function-justify-hours">
+          <primary>justify_hours</primary>
+         </indexterm>
+         <function>justify_hours</function> ( <type>interval</type> )
+         <returnvalue>interval</returnvalue>
+        </para>
+        <para>
+         Adjust interval, converting 24-hour time periods to days
+        </para>
+        <para>
+         <literal>justify_hours(interval '50 hours 10 minutes')</literal>
+         <returnvalue>2 days 02:10:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>justify_interval</primary>
+         </indexterm>
+         <function>justify_interval</function> ( <type>interval</type> )
+         <returnvalue>interval</returnvalue>
+        </para>
+        <para>
+         Adjust interval using <function>justify_days</function>
+         and <function>justify_hours</function>, with additional sign
+         adjustments
+        </para>
+        <para>
+         <literal>justify_interval(interval '1 mon -1 hour')</literal>
+         <returnvalue>29 days 23:00:00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>localtime</primary>
+         </indexterm>
+         <function>localtime</function>
+         <returnvalue>time</returnvalue>
+        </para>
+        <para>
+         Current time of day;
+         see <xref linkend="functions-datetime-current"/>
+        </para>
+        <para>
+         <literal>localtime</literal>
+         <returnvalue>14:39:53.662522</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <function>localtime</function> ( <type>integer</type> )
+         <returnvalue>time</returnvalue>
+        </para>
+        <para>
+         Current time of day, with limited precision;
+         see <xref linkend="functions-datetime-current"/>
+        </para>
+        <para>
+         <literal>localtime(0)</literal>
+         <returnvalue>14:39:53</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>localtimestamp</primary>
+         </indexterm>
+         <function>localtimestamp</function>
+         <returnvalue>timestamp</returnvalue>
+        </para>
+        <para>
+         Current date and time (start of current transaction);
+         see <xref linkend="functions-datetime-current"/>
+        </para>
+        <para>
+         <literal>localtimestamp</literal>
+         <returnvalue>2019-12-23 14:39:53.662522</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <function>localtimestamp</function> ( <type>integer</type> )
+         <returnvalue>timestamp</returnvalue>
+        </para>
+        <para>
+         Current date and time (start of current
+         transaction), with limited precision;
+         see <xref linkend="functions-datetime-current"/>
+        </para>
+        <para>
+         <literal>localtimestamp(2)</literal>
+         <returnvalue>2019-12-23 14:39:53.66</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>make_date</primary>
+         </indexterm>
+         <function>make_date</function> ( <parameter>year</parameter> <type>int</type>,
+         <parameter>month</parameter> <type>int</type>,
+         <parameter>day</parameter> <type>int</type> )
+         <returnvalue>date</returnvalue>
+        </para>
+        <para>
+         Create date from year, month and day fields
+         (negative years signify BC)
+        </para>
+        <para>
+         <literal>make_date(2013, 7, 15)</literal>
+         <returnvalue>2013-07-15</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature"><indexterm>
+          <primary>make_interval</primary>
+         </indexterm>
+         <function>make_interval</function> ( <optional> <parameter>years</parameter> <type>int</type>
+         <optional>, <parameter>months</parameter> <type>int</type>
+         <optional>, <parameter>weeks</parameter> <type>int</type>
+         <optional>, <parameter>days</parameter> <type>int</type>
+         <optional>, <parameter>hours</parameter> <type>int</type>
+         <optional>, <parameter>mins</parameter> <type>int</type>
+         <optional>, <parameter>secs</parameter> <type>double precision</type>
+         </optional></optional></optional></optional></optional></optional></optional> )
+         <returnvalue>interval</returnvalue>
+        </para>
+        <para>
+         Create interval from years, months, weeks, days, hours, minutes and
+         seconds fields, each of which can default to zero
+        </para>
+        <para>
+         <literal>make_interval(days =&gt; 10)</literal>
+         <returnvalue>10 days</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>make_time</primary>
+         </indexterm>
+         <function>make_time</function> ( <parameter>hour</parameter> <type>int</type>,
+         <parameter>min</parameter> <type>int</type>,
+         <parameter>sec</parameter> <type>double precision</type> )
+         <returnvalue>time</returnvalue>
+        </para>
+        <para>
+         Create time from hour, minute and seconds fields
+        </para>
+        <para>
+         <literal>make_time(8, 15, 23.5)</literal>
+         <returnvalue>08:15:23.5</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>make_timestamp</primary>
+         </indexterm>
+         <function>make_timestamp</function> ( <parameter>year</parameter> <type>int</type>,
+         <parameter>month</parameter> <type>int</type>,
+         <parameter>day</parameter> <type>int</type>,
+         <parameter>hour</parameter> <type>int</type>,
+         <parameter>min</parameter> <type>int</type>,
+         <parameter>sec</parameter> <type>double precision</type> )
+         <returnvalue>timestamp</returnvalue>
+        </para>
+        <para>
+         Create timestamp from year, month, day, hour, minute and seconds fields
+         (negative years signify BC)
+        </para>
+        <para>
+         <literal>make_timestamp(2013, 7, 15, 8, 15, 23.5)</literal>
+         <returnvalue>2013-07-15 08:15:23.5</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>make_timestamptz</primary>
+         </indexterm>
+         <function>make_timestamptz</function> ( <parameter>year</parameter> <type>int</type>,
+         <parameter>month</parameter> <type>int</type>,
+         <parameter>day</parameter> <type>int</type>,
+         <parameter>hour</parameter> <type>int</type>,
+         <parameter>min</parameter> <type>int</type>,
+         <parameter>sec</parameter> <type>double precision</type>
+         <optional>, <parameter>timezone</parameter> <type>text</type> </optional> )
+         <returnvalue>timestamp with time zone</returnvalue>
+        </para>
+        <para>
+         Create timestamp with time zone from year, month, day, hour, minute
+         and seconds fields (negative years signify BC).
+         If <parameter>timezone</parameter> is not
+         specified, the current time zone is used; the examples assume the
+         session time zone is <literal>Europe/London</literal>
+        </para>
+        <para>
+         <literal>make_timestamptz(2013, 7, 15, 8, 15, 23.5)</literal>
+         <returnvalue>2013-07-15 08:15:23.5+01</returnvalue>
+        </para>
+        <para>
+         <literal>make_timestamptz(2013, 7, 15, 8, 15, 23.5, 'America/New_York')</literal>
+         <returnvalue>2013-07-15 13:15:23.5+01</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>now</primary>
+         </indexterm>
+         <function>now</function> ( )
+         <returnvalue>timestamp with time zone</returnvalue>
+        </para>
+        <para>
+         Current date and time (start of current transaction);
+         see <xref linkend="functions-datetime-current"/>
+        </para>
+        <para>
+         <literal>now()</literal>
+         <returnvalue>2019-12-23 14:39:53.662522-05</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>statement_timestamp</primary>
+         </indexterm>
+         <function>statement_timestamp</function> ( )
+         <returnvalue>timestamp with time zone</returnvalue>
+        </para>
+        <para>
+         Current date and time (start of current statement);
+         see <xref linkend="functions-datetime-current"/>
+        </para>
+        <para>
+         <literal>statement_timestamp()</literal>
+         <returnvalue>2019-12-23 14:39:53.662522-05</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>timeofday</primary>
+         </indexterm>
+         <function>timeofday</function> ( )
+         <returnvalue>text</returnvalue>
+        </para>
+        <para>
+         Current date and time
+         (like <function>clock_timestamp</function>, but as a <type>text</type> string);
+         see <xref linkend="functions-datetime-current"/>
+        </para>
+        <para>
+         <literal>timeofday()</literal>
+         <returnvalue>Mon Dec 23 14:39:53.662522 2019 EST</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>transaction_timestamp</primary>
+         </indexterm>
+         <function>transaction_timestamp</function> ( )
+         <returnvalue>timestamp with time zone</returnvalue>
+        </para>
+        <para>
+         Current date and time (start of current transaction);
+         see <xref linkend="functions-datetime-current"/>
+        </para>
+        <para>
+         <literal>transaction_timestamp()</literal>
+         <returnvalue>2019-12-23 14:39:53.662522-05</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>to_timestamp</primary>
+         </indexterm>
+         <function>to_timestamp</function> ( <type>double precision</type> )
+         <returnvalue>timestamp with time zone</returnvalue>
+        </para>
+        <para>
+         Convert Unix epoch (seconds since 1970-01-01 00:00:00+00) to
+         timestamp with time zone
+        </para>
+        <para>
+         <literal>to_timestamp(1284352323)</literal>
+         <returnvalue>2010-09-13 04:32:03+00</returnvalue>
+        </para></entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+   <para>
+    <indexterm>
+      <primary>OVERLAPS</primary>
+    </indexterm>
+    In addition to these functions, the SQL <literal>OVERLAPS</literal> operator is
+    supported:
+<synopsis>
+(<replaceable>start1</replaceable>, <replaceable>end1</replaceable>) OVERLAPS (<replaceable>start2</replaceable>, <replaceable>end2</replaceable>)
+(<replaceable>start1</replaceable>, <replaceable>length1</replaceable>) OVERLAPS (<replaceable>start2</replaceable>, <replaceable>length2</replaceable>)
+</synopsis>
+    This expression yields true when two time periods (defined by their
+    endpoints) overlap, false when they do not overlap.  The endpoints
+    can be specified as pairs of dates, times, or time stamps; or as
+    a date, time, or time stamp followed by an interval.  When a pair
+    of values is provided, either the start or the end can be written
+    first; <literal>OVERLAPS</literal> automatically takes the earlier value
+    of the pair as the start.  Each time period is considered to
+    represent the half-open interval <replaceable>start</replaceable> <literal>&lt;=</literal>
+    <replaceable>time</replaceable> <literal>&lt;</literal> <replaceable>end</replaceable>, unless
+    <replaceable>start</replaceable> and <replaceable>end</replaceable> are equal in which case it
+    represents that single time instant.  This means for instance that two
+    time periods with only an endpoint in common do not overlap.
+   </para>
+
+<screen>
+SELECT (DATE '2001-02-16', DATE '2001-12-21') OVERLAPS
+       (DATE '2001-10-30', DATE '2002-10-30');
+<lineannotation>Result: </lineannotation><computeroutput>true</computeroutput>
+SELECT (DATE '2001-02-16', INTERVAL '100 days') OVERLAPS
+       (DATE '2001-10-30', DATE '2002-10-30');
+<lineannotation>Result: </lineannotation><computeroutput>false</computeroutput>
+SELECT (DATE '2001-10-29', DATE '2001-10-30') OVERLAPS
+       (DATE '2001-10-30', DATE '2001-10-31');
+<lineannotation>Result: </lineannotation><computeroutput>false</computeroutput>
+SELECT (DATE '2001-10-30', DATE '2001-10-30') OVERLAPS
+       (DATE '2001-10-30', DATE '2001-10-31');
+<lineannotation>Result: </lineannotation><computeroutput>true</computeroutput>
+</screen>
+
+  <para>
+   When adding an <type>interval</type> value to (or subtracting an
+   <type>interval</type> value from) a <type>timestamp</type>
+   or <type>timestamp with time zone</type> value, the months, days, and
+   microseconds fields of the <type>interval</type> value are handled in turn.
+   First, a nonzero months field advances or decrements the date of the
+   timestamp by the indicated number of months, keeping the day of month the
+   same unless it would be past the end of the new month, in which case the
+   last day of that month is used.  (For example, March 31 plus 1 month
+   becomes April 30, but March 31 plus 2 months becomes May 31.)
+   Then the days field advances or decrements the date of the timestamp by
+   the indicated number of days.  In both these steps the local time of day
+   is kept the same.  Finally, if there is a nonzero microseconds field, it
+   is added or subtracted literally.
+   When doing arithmetic on a <type>timestamp with time zone</type> value in
+   a time zone that recognizes DST, this means that adding or subtracting
+   (say) <literal>interval '1 day'</literal> does not necessarily have the
+   same result as adding or subtracting <literal>interval '24
+   hours'</literal>.
+   For example, with the session time zone set
+   to <literal>America/Denver</literal>:
+<screen>
+SELECT timestamp with time zone '2005-04-02 12:00:00-07' + interval '1 day';
+<lineannotation>Result: </lineannotation><computeroutput>2005-04-03 12:00:00-06</computeroutput>
+SELECT timestamp with time zone '2005-04-02 12:00:00-07' + interval '24 hours';
+<lineannotation>Result: </lineannotation><computeroutput>2005-04-03 13:00:00-06</computeroutput>
+</screen>
+   This happens because an hour was skipped due to a change in daylight saving
+   time at <literal>2005-04-03 02:00:00</literal> in time zone
+   <literal>America/Denver</literal>.
+  </para>
+
+  <para>
+   Note there can be ambiguity in the <literal>months</literal> field returned by
+   <function>age</function> because different months have different numbers of
+   days.  <productname>PostgreSQL</productname>'s approach uses the month from the
+   earlier of the two dates when calculating partial months.  For example,
+   <literal>age('2004-06-01', '2004-04-30')</literal> uses April to yield
+   <literal>1 mon 1 day</literal>, while using May would yield <literal>1 mon 2
+   days</literal> because May has 31 days, while April has only 30.
+  </para>
+
+  <para>
+   Subtraction of dates and timestamps can also be complex.  One conceptually
+   simple way to perform subtraction is to convert each value to a number
+   of seconds using <literal>EXTRACT(EPOCH FROM ...)</literal>, then subtract the
+   results; this produces the
+   number of <emphasis>seconds</emphasis> between the two values.  This will adjust
+   for the number of days in each month, timezone changes, and daylight
+   saving time adjustments.  Subtraction of date or timestamp
+   values with the <quote><literal>-</literal></quote> operator
+   returns the number of days (24-hours) and hours/minutes/seconds
+   between the values, making the same adjustments.  The <function>age</function>
+   function returns years, months, days, and hours/minutes/seconds,
+   performing field-by-field subtraction and then adjusting for negative
+   field values.  The following queries illustrate the differences in these
+   approaches.  The sample results were produced with <literal>timezone
+   = 'US/Eastern'</literal>; there is a daylight saving time change between the
+   two dates used:
+  </para>
+
+<screen>
+SELECT EXTRACT(EPOCH FROM timestamptz '2013-07-01 12:00:00') -
+       EXTRACT(EPOCH FROM timestamptz '2013-03-01 12:00:00');
+<lineannotation>Result: </lineannotation><computeroutput>10537200.000000</computeroutput>
+SELECT (EXTRACT(EPOCH FROM timestamptz '2013-07-01 12:00:00') -
+        EXTRACT(EPOCH FROM timestamptz '2013-03-01 12:00:00'))
+        / 60 / 60 / 24;
+<lineannotation>Result: </lineannotation><computeroutput>121.9583333333333333</computeroutput>
+SELECT timestamptz '2013-07-01 12:00:00' - timestamptz '2013-03-01 12:00:00';
+<lineannotation>Result: </lineannotation><computeroutput>121 days 23:00:00</computeroutput>
+SELECT age(timestamptz '2013-07-01 12:00:00', timestamptz '2013-03-01 12:00:00');
+<lineannotation>Result: </lineannotation><computeroutput>4 mons</computeroutput>
+</screen>
+
+  <sect2 id="functions-datetime-extract">
+   <title><function>EXTRACT</function>, <function>date_part</function></title>
+
+   <indexterm>
+    <primary>date_part</primary>
+   </indexterm>
+   <indexterm>
+    <primary>extract</primary>
+   </indexterm>
+
+<synopsis>
+EXTRACT(<replaceable>field</replaceable> FROM <replaceable>source</replaceable>)
+</synopsis>
+
+   <para>
+    The <function>extract</function> function retrieves subfields
+    such as year or hour from date/time values.
+    <replaceable>source</replaceable> must be a value expression of
+    type <type>timestamp</type>, <type>date</type>, <type>time</type>,
+    or <type>interval</type>.  (Timestamps and times can be with or
+    without time zone.)
+    <replaceable>field</replaceable> is an identifier or
+    string that selects what field to extract from the source value.
+    Not all fields are valid for every input data type; for example, fields
+    smaller than a day cannot be extracted from a <type>date</type>, while
+    fields of a day or more cannot be extracted from a <type>time</type>.
+    The <function>extract</function> function returns values of type
+    <type>numeric</type>.
+   </para>
+
+   <para>
+    The following are valid field names:
+
+    <!-- alphabetical -->
+    <variablelist>
+     <varlistentry>
+      <term><literal>century</literal></term>
+      <listitem>
+       <para>
+        The century; for <type>interval</type> values, the year field
+        divided by 100
+       </para>
+
+<screen>
+SELECT EXTRACT(CENTURY FROM TIMESTAMP '2000-12-16 12:21:13');
+<lineannotation>Result: </lineannotation><computeroutput>20</computeroutput>
+SELECT EXTRACT(CENTURY FROM TIMESTAMP '2001-02-16 20:38:40');
+<lineannotation>Result: </lineannotation><computeroutput>21</computeroutput>
+SELECT EXTRACT(CENTURY FROM DATE '0001-01-01 AD');
+<lineannotation>Result: </lineannotation><computeroutput>1</computeroutput>
+SELECT EXTRACT(CENTURY FROM DATE '0001-12-31 BC');
+<lineannotation>Result: </lineannotation><computeroutput>-1</computeroutput>
+SELECT EXTRACT(CENTURY FROM INTERVAL '2001 years');
+<lineannotation>Result: </lineannotation><computeroutput>20</computeroutput>
+</screen>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>day</literal></term>
+      <listitem>
+       <para>
+        The day of the month (1&ndash;31); for <type>interval</type>
+        values, the number of days
+       </para>
+
+<screen>
+SELECT EXTRACT(DAY FROM TIMESTAMP '2001-02-16 20:38:40');
+<lineannotation>Result: </lineannotation><computeroutput>16</computeroutput>
+SELECT EXTRACT(DAY FROM INTERVAL '40 days 1 minute');
+<lineannotation>Result: </lineannotation><computeroutput>40</computeroutput>
+</screen>
+
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>decade</literal></term>
+      <listitem>
+       <para>
+        The year field divided by 10
+       </para>
+
+<screen>
+SELECT EXTRACT(DECADE FROM TIMESTAMP '2001-02-16 20:38:40');
+<lineannotation>Result: </lineannotation><computeroutput>200</computeroutput>
+</screen>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>dow</literal></term>
+      <listitem>
+       <para>
+        The day of the week as Sunday (<literal>0</literal>) to
+        Saturday (<literal>6</literal>)
+       </para>
+
+<screen>
+SELECT EXTRACT(DOW FROM TIMESTAMP '2001-02-16 20:38:40');
+<lineannotation>Result: </lineannotation><computeroutput>5</computeroutput>
+</screen>
+       <para>
+        Note that <function>extract</function>'s day of the week numbering
+        differs from that of the <function>to_char(...,
+        'D')</function> function.
+       </para>
+
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>doy</literal></term>
+      <listitem>
+       <para>
+        The day of the year (1&ndash;365/366)
+       </para>
+
+<screen>
+SELECT EXTRACT(DOY FROM TIMESTAMP '2001-02-16 20:38:40');
+<lineannotation>Result: </lineannotation><computeroutput>47</computeroutput>
+</screen>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>epoch</literal></term>
+      <listitem>
+       <para>
+        For <type>timestamp with time zone</type> values, the
+        number of seconds since 1970-01-01 00:00:00 UTC (negative for
+        timestamps before that);
+        for <type>date</type> and <type>timestamp</type> values, the
+        nominal number of seconds since 1970-01-01 00:00:00,
+        without regard to timezone or daylight-savings rules;
+        for <type>interval</type> values, the total number
+        of seconds in the interval
+       </para>
+
+<screen>
+SELECT EXTRACT(EPOCH FROM TIMESTAMP WITH TIME ZONE '2001-02-16 20:38:40.12-08');
+<lineannotation>Result: </lineannotation><computeroutput>982384720.120000</computeroutput>
+SELECT EXTRACT(EPOCH FROM TIMESTAMP '2001-02-16 20:38:40.12');
+<lineannotation>Result: </lineannotation><computeroutput>982355920.120000</computeroutput>
+SELECT EXTRACT(EPOCH FROM INTERVAL '5 days 3 hours');
+<lineannotation>Result: </lineannotation><computeroutput>442800.000000</computeroutput>
+</screen>
+
+       <para>
+        You can convert an epoch value back to a <type>timestamp with time zone</type>
+        with <function>to_timestamp</function>:
+       </para>
+<screen>
+SELECT to_timestamp(982384720.12);
+<lineannotation>Result: </lineannotation><computeroutput>2001-02-17 04:38:40.12+00</computeroutput>
+</screen>
+
+       <para>
+        Beware that applying <function>to_timestamp</function> to an epoch
+        extracted from a <type>date</type> or <type>timestamp</type> value
+        could produce a misleading result: the result will effectively
+        assume that the original value had been given in UTC, which might
+        not be the case.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>hour</literal></term>
+      <listitem>
+       <para>
+        The hour field (0&ndash;23 in timestamps, unrestricted in
+        intervals)
+       </para>
+
+<screen>
+SELECT EXTRACT(HOUR FROM TIMESTAMP '2001-02-16 20:38:40');
+<lineannotation>Result: </lineannotation><computeroutput>20</computeroutput>
+</screen>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>isodow</literal></term>
+      <listitem>
+       <para>
+        The day of the week as Monday (<literal>1</literal>) to
+        Sunday (<literal>7</literal>)
+       </para>
+
+<screen>
+SELECT EXTRACT(ISODOW FROM TIMESTAMP '2001-02-18 20:38:40');
+<lineannotation>Result: </lineannotation><computeroutput>7</computeroutput>
+</screen>
+       <para>
+        This is identical to <literal>dow</literal> except for Sunday.  This
+        matches the <acronym>ISO</acronym> 8601 day of the week numbering.
+       </para>
+
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>isoyear</literal></term>
+      <listitem>
+       <para>
+        The <acronym>ISO</acronym> 8601 week-numbering year that the date
+        falls in
+       </para>
+
+<screen>
+SELECT EXTRACT(ISOYEAR FROM DATE '2006-01-01');
+<lineannotation>Result: </lineannotation><computeroutput>2005</computeroutput>
+SELECT EXTRACT(ISOYEAR FROM DATE '2006-01-02');
+<lineannotation>Result: </lineannotation><computeroutput>2006</computeroutput>
+</screen>
+
+       <para>
+        Each <acronym>ISO</acronym> 8601 week-numbering year begins with the
+        Monday of the week containing the 4th of January, so in early
+        January or late December the <acronym>ISO</acronym> year may be
+        different from the Gregorian year.  See the <literal>week</literal>
+        field for more information.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>julian</literal></term>
+      <listitem>
+       <para>
+        The <firstterm>Julian Date</firstterm> corresponding to the
+        date or timestamp.  Timestamps
+        that are not local midnight result in a fractional value.  See
+        <xref linkend="datetime-julian-dates"/> for more information.
+       </para>
+
+<screen>
+SELECT EXTRACT(JULIAN FROM DATE '2006-01-01');
+<lineannotation>Result: </lineannotation><computeroutput>2453737</computeroutput>
+SELECT EXTRACT(JULIAN FROM TIMESTAMP '2006-01-01 12:00');
+<lineannotation>Result: </lineannotation><computeroutput>2453737.50000000000000000000</computeroutput>
+</screen>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>microseconds</literal></term>
+      <listitem>
+       <para>
+        The seconds field, including fractional parts, multiplied by 1
+        000 000;  note that this includes full seconds
+       </para>
+
+<screen>
+SELECT EXTRACT(MICROSECONDS FROM TIME '17:12:28.5');
+<lineannotation>Result: </lineannotation><computeroutput>28500000</computeroutput>
+</screen>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>millennium</literal></term>
+      <listitem>
+       <para>
+        The millennium; for <type>interval</type> values, the year field
+        divided by 1000
+       </para>
+
+<screen>
+SELECT EXTRACT(MILLENNIUM FROM TIMESTAMP '2001-02-16 20:38:40');
+<lineannotation>Result: </lineannotation><computeroutput>3</computeroutput>
+SELECT EXTRACT(MILLENNIUM FROM INTERVAL '2001 years');
+<lineannotation>Result: </lineannotation><computeroutput>2</computeroutput>
+</screen>
+
+       <para>
+        Years in the 1900s are in the second millennium.
+        The third millennium started January 1, 2001.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>milliseconds</literal></term>
+      <listitem>
+       <para>
+        The seconds field, including fractional parts, multiplied by
+        1000.  Note that this includes full seconds.
+       </para>
+
+<screen>
+SELECT EXTRACT(MILLISECONDS FROM TIME '17:12:28.5');
+<lineannotation>Result: </lineannotation><computeroutput>28500.000</computeroutput>
+</screen>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>minute</literal></term>
+      <listitem>
+       <para>
+        The minutes field (0&ndash;59)
+       </para>
+
+<screen>
+SELECT EXTRACT(MINUTE FROM TIMESTAMP '2001-02-16 20:38:40');
+<lineannotation>Result: </lineannotation><computeroutput>38</computeroutput>
+</screen>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>month</literal></term>
+      <listitem>
+       <para>
+        The number of the month within the year (1&ndash;12);
+        for <type>interval</type> values, the number of months modulo 12
+        (0&ndash;11)
+       </para>
+
+<screen>
+SELECT EXTRACT(MONTH FROM TIMESTAMP '2001-02-16 20:38:40');
+<lineannotation>Result: </lineannotation><computeroutput>2</computeroutput>
+SELECT EXTRACT(MONTH FROM INTERVAL '2 years 3 months');
+<lineannotation>Result: </lineannotation><computeroutput>3</computeroutput>
+SELECT EXTRACT(MONTH FROM INTERVAL '2 years 13 months');
+<lineannotation>Result: </lineannotation><computeroutput>1</computeroutput>
+</screen>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>quarter</literal></term>
+      <listitem>
+       <para>
+        The quarter of the year (1&ndash;4) that the date is in;
+        for <type>interval</type> values, the month field divided by 3
+        plus 1
+       </para>
+
+<screen>
+SELECT EXTRACT(QUARTER FROM TIMESTAMP '2001-02-16 20:38:40');
+<lineannotation>Result: </lineannotation><computeroutput>1</computeroutput>
+SELECT EXTRACT(QUARTER FROM INTERVAL '1 year 6 months');
+<lineannotation>Result: </lineannotation><computeroutput>3</computeroutput>
+</screen>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>second</literal></term>
+      <listitem>
+       <para>
+        The seconds field, including any fractional seconds
+       </para>
+
+<screen>
+SELECT EXTRACT(SECOND FROM TIMESTAMP '2001-02-16 20:38:40');
+<lineannotation>Result: </lineannotation><computeroutput>40.000000</computeroutput>
+SELECT EXTRACT(SECOND FROM TIME '17:12:28.5');
+<lineannotation>Result: </lineannotation><computeroutput>28.500000</computeroutput>
+</screen>
+      </listitem>
+     </varlistentry>
+     <varlistentry>
+      <term><literal>timezone</literal></term>
+      <listitem>
+       <para>
+        The time zone offset from UTC, measured in seconds.  Positive values
+        correspond to time zones east of UTC, negative values to
+        zones west of UTC.  (Technically,
+        <productname>PostgreSQL</productname> does not use UTC because
+        leap seconds are not handled.)
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>timezone_hour</literal></term>
+      <listitem>
+       <para>
+        The hour component of the time zone offset
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>timezone_minute</literal></term>
+      <listitem>
+       <para>
+        The minute component of the time zone offset
+       </para>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>week</literal></term>
+      <listitem>
+       <para>
+        The number of the <acronym>ISO</acronym> 8601 week-numbering week of
+        the year.  By definition, ISO weeks start on Mondays and the first
+        week of a year contains January 4 of that year.  In other words, the
+        first Thursday of a year is in week 1 of that year.
+       </para>
+       <para>
+        In the ISO week-numbering system, it is possible for early-January
+        dates to be part of the 52nd or 53rd week of the previous year, and for
+        late-December dates to be part of the first week of the next year.
+        For example, <literal>2005-01-01</literal> is part of the 53rd week of year
+        2004, and <literal>2006-01-01</literal> is part of the 52nd week of year
+        2005, while <literal>2012-12-31</literal> is part of the first week of 2013.
+        It's recommended to use the <literal>isoyear</literal> field together with
+        <literal>week</literal> to get consistent results.
+       </para>
+
+       <para>
+        For <type>interval</type> values, the week field is simply the number
+        of integral days divided by 7.
+       </para>
+
+<screen>
+SELECT EXTRACT(WEEK FROM TIMESTAMP '2001-02-16 20:38:40');
+<lineannotation>Result: </lineannotation><computeroutput>7</computeroutput>
+SELECT EXTRACT(WEEK FROM INTERVAL '13 days 24 hours');
+<lineannotation>Result: </lineannotation><computeroutput>1</computeroutput>
+</screen>
+      </listitem>
+     </varlistentry>
+
+     <varlistentry>
+      <term><literal>year</literal></term>
+      <listitem>
+       <para>
+        The year field.  Keep in mind there is no <literal>0 AD</literal>, so subtracting
+        <literal>BC</literal> years from <literal>AD</literal> years should be done with care.
+       </para>
+
+<screen>
+SELECT EXTRACT(YEAR FROM TIMESTAMP '2001-02-16 20:38:40');
+<lineannotation>Result: </lineannotation><computeroutput>2001</computeroutput>
+</screen>
+      </listitem>
+     </varlistentry>
+
+    </variablelist>
+   </para>
+
+   <para>
+    When processing an <type>interval</type> value,
+    the <function>extract</function> function produces field values that
+    match the interpretation used by the interval output function.  This
+    can produce surprising results if one starts with a non-normalized
+    interval representation, for example:
+<screen>
+SELECT INTERVAL '80 minutes';
+<lineannotation>Result: </lineannotation><computeroutput>01:20:00</computeroutput>
+SELECT EXTRACT(MINUTES FROM INTERVAL '80 minutes');
+<lineannotation>Result: </lineannotation><computeroutput>20</computeroutput>
+</screen>
+   </para>
+
+   <note>
+    <para>
+     When the input value is +/-Infinity, <function>extract</function> returns
+     +/-Infinity for monotonically-increasing fields (<literal>epoch</literal>,
+     <literal>julian</literal>, <literal>year</literal>, <literal>isoyear</literal>,
+     <literal>decade</literal>, <literal>century</literal>, and <literal>millennium</literal>
+     for <type>timestamp</type> inputs; <literal>epoch</literal>, <literal>hour</literal>,
+     <literal>day</literal>, <literal>year</literal>, <literal>decade</literal>,
+     <literal>century</literal>, and <literal>millennium</literal> for
+     <type>interval</type> inputs).
+     For other fields, NULL is returned.  <productname>PostgreSQL</productname>
+     versions before 9.6 returned zero for all cases of infinite input.
+    </para>
+   </note>
+
+   <para>
+    The <function>extract</function> function is primarily intended
+    for computational processing.  For formatting date/time values for
+    display, see <xref linkend="functions-formatting"/>.
+   </para>
+
+   <para>
+    The <function>date_part</function> function is modeled on the traditional
+    <productname>Ingres</productname> equivalent to the
+    <acronym>SQL</acronym>-standard function <function>extract</function>:
+<synopsis>
+date_part('<replaceable>field</replaceable>', <replaceable>source</replaceable>)
+</synopsis>
+    Note that here the <replaceable>field</replaceable> parameter needs to
+    be a string value, not a name.  The valid field names for
+    <function>date_part</function> are the same as for
+    <function>extract</function>.
+    For historical reasons, the <function>date_part</function> function
+    returns values of type <type>double precision</type>.  This can result in
+    a loss of precision in certain uses.  Using <function>extract</function>
+    is recommended instead.
+   </para>
+
+<screen>
+SELECT date_part('day', TIMESTAMP '2001-02-16 20:38:40');
+<lineannotation>Result: </lineannotation><computeroutput>16</computeroutput>
+SELECT date_part('hour', INTERVAL '4 hours 3 minutes');
+<lineannotation>Result: </lineannotation><computeroutput>4</computeroutput>
+</screen>
+
+  </sect2>
+
+  <sect2 id="functions-datetime-trunc">
+   <title><function>date_trunc</function></title>
+
+   <indexterm>
+    <primary>date_trunc</primary>
+   </indexterm>
+
+   <para>
+    The function <function>date_trunc</function> is conceptually
+    similar to the <function>trunc</function> function for numbers.
+   </para>
+
+   <para>
+<synopsis>
+date_trunc(<replaceable>field</replaceable>, <replaceable>source</replaceable> <optional>, <replaceable>time_zone</replaceable> </optional>)
+</synopsis>
+    <replaceable>source</replaceable> is a value expression of type
+    <type>timestamp</type>, <type>timestamp with time zone</type>,
+    or <type>interval</type>.
+    (Values of type <type>date</type> and
+    <type>time</type> are cast automatically to <type>timestamp</type> or
+    <type>interval</type>, respectively.)
+    <replaceable>field</replaceable> selects to which precision to
+    truncate the input value.  The return value is likewise of type
+    <type>timestamp</type>, <type>timestamp with time zone</type>,
+    or <type>interval</type>,
+    and it has all fields that are less significant than the
+    selected one set to zero (or one, for day and month).
+   </para>
+
+   <para>
+    Valid values for <replaceable>field</replaceable> are:
+    <simplelist>
+     <member><literal>microseconds</literal></member>
+     <member><literal>milliseconds</literal></member>
+     <member><literal>second</literal></member>
+     <member><literal>minute</literal></member>
+     <member><literal>hour</literal></member>
+     <member><literal>day</literal></member>
+     <member><literal>week</literal></member>
+     <member><literal>month</literal></member>
+     <member><literal>quarter</literal></member>
+     <member><literal>year</literal></member>
+     <member><literal>decade</literal></member>
+     <member><literal>century</literal></member>
+     <member><literal>millennium</literal></member>
+    </simplelist>
+   </para>
+
+   <para>
+    When the input value is of type <type>timestamp with time zone</type>,
+    the truncation is performed with respect to a particular time zone;
+    for example, truncation to <literal>day</literal> produces a value that
+    is midnight in that zone.  By default, truncation is done with respect
+    to the current <xref linkend="guc-timezone"/> setting, but the
+    optional <replaceable>time_zone</replaceable> argument can be provided
+    to specify a different time zone.  The time zone name can be specified
+    in any of the ways described in <xref linkend="datatype-timezones"/>.
+   </para>
+
+   <para>
+    A time zone cannot be specified when processing <type>timestamp without
+    time zone</type> or <type>interval</type> inputs.  These are always
+    taken at face value.
+   </para>
+
+   <para>
+    Examples (assuming the local time zone is <literal>America/New_York</literal>):
+<screen>
+SELECT date_trunc('hour', TIMESTAMP '2001-02-16 20:38:40');
+<lineannotation>Result: </lineannotation><computeroutput>2001-02-16 20:00:00</computeroutput>
+SELECT date_trunc('year', TIMESTAMP '2001-02-16 20:38:40');
+<lineannotation>Result: </lineannotation><computeroutput>2001-01-01 00:00:00</computeroutput>
+SELECT date_trunc('day', TIMESTAMP WITH TIME ZONE '2001-02-16 20:38:40+00');
+<lineannotation>Result: </lineannotation><computeroutput>2001-02-16 00:00:00-05</computeroutput>
+SELECT date_trunc('day', TIMESTAMP WITH TIME ZONE '2001-02-16 20:38:40+00', 'Australia/Sydney');
+<lineannotation>Result: </lineannotation><computeroutput>2001-02-16 08:00:00-05</computeroutput>
+SELECT date_trunc('hour', INTERVAL '3 days 02:47:33');
+<lineannotation>Result: </lineannotation><computeroutput>3 days 02:00:00</computeroutput>
+</screen>
+   </para>
+  </sect2>
+
+  <sect2 id="functions-datetime-bin">
+   <title><function>date_bin</function></title>
+
+   <indexterm>
+    <primary>date_bin</primary>
+   </indexterm>
+
+   <para>
+    The function <function>date_bin</function> <quote>bins</quote> the input
+    timestamp into the specified interval (the <firstterm>stride</firstterm>)
+    aligned with a specified origin.
+   </para>
+
+   <para>
+<synopsis>
+date_bin(<replaceable>stride</replaceable>, <replaceable>source</replaceable>, <replaceable>origin</replaceable>)
+</synopsis>
+    <replaceable>source</replaceable> is a value expression of type
+    <type>timestamp</type> or <type>timestamp with time zone</type>.  (Values
+    of type <type>date</type> are cast automatically to
+    <type>timestamp</type>.)  <replaceable>stride</replaceable> is a value
+    expression of type <type>interval</type>.  The return value is likewise
+    of type <type>timestamp</type> or <type>timestamp with time zone</type>,
+    and it marks the beginning of the bin into which the
+    <replaceable>source</replaceable> is placed.
+   </para>
+
+   <para>
+    Examples:
+<screen>
+SELECT date_bin('15 minutes', TIMESTAMP '2020-02-11 15:44:17', TIMESTAMP '2001-01-01');
+<lineannotation>Result: </lineannotation><computeroutput>2020-02-11 15:30:00</computeroutput>
+SELECT date_bin('15 minutes', TIMESTAMP '2020-02-11 15:44:17', TIMESTAMP '2001-01-01 00:02:30');
+<lineannotation>Result: </lineannotation><computeroutput>2020-02-11 15:32:30</computeroutput>
+</screen>
+   </para>
+
+   <para>
+    In the case of full units (1 minute, 1 hour, etc.), it gives the same result as
+    the analogous <function>date_trunc</function> call, but the difference is
+    that <function>date_bin</function> can truncate to an arbitrary interval.
+   </para>
+
+   <para>
+    The <parameter>stride</parameter> interval must be greater than zero and
+    cannot contain units of month or larger.
+   </para>
+  </sect2>
+
+  <sect2 id="functions-datetime-zoneconvert">
+   <title><literal>AT TIME ZONE</literal> and <literal>AT LOCAL</literal></title>
+
+   <indexterm>
+    <primary>time zone</primary>
+    <secondary>conversion</secondary>
+   </indexterm>
+
+   <indexterm>
+    <primary>AT TIME ZONE</primary>
+   </indexterm>
+
+   <indexterm>
+    <primary>AT LOCAL</primary>
+   </indexterm>
+
+   <para>
+    The <literal>AT TIME ZONE</literal> operator converts time
+    stamp <emphasis>without</emphasis> time zone to/from
+    time stamp <emphasis>with</emphasis> time zone, and
+    <type>time with time zone</type> values to different time
+    zones. <xref linkend="functions-datetime-zoneconvert-table"/> shows its
+    variants.
+   </para>
+
+    <table id="functions-datetime-zoneconvert-table">
+     <title><literal>AT TIME ZONE</literal> and <literal>AT LOCAL</literal> Variants</title>
+     <tgroup cols="1">
+      <thead>
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         Operator
+        </para>
+        <para>
+         Description
+        </para>
+        <para>
+         Example(s)
+        </para></entry>
+       </row>
+      </thead>
+
+      <tbody>
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>timestamp without time zone</type> <literal>AT TIME ZONE</literal> <replaceable>zone</replaceable>
+         <returnvalue>timestamp with time zone</returnvalue>
+        </para>
+        <para>
+         Converts given time stamp <emphasis>without</emphasis> time zone to
+         time stamp <emphasis>with</emphasis> time zone, assuming the given
+         value is in the named time zone.
+        </para>
+        <para>
+         <literal>timestamp '2001-02-16 20:38:40' at time zone 'America/Denver'</literal>
+         <returnvalue>2001-02-17 03:38:40+00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>timestamp without time zone</type> <literal>AT LOCAL</literal>
+         <returnvalue>timestamp with time zone</returnvalue>
+        </para>
+        <para>
+         Converts given time stamp <emphasis>without</emphasis> time zone to
+         time stamp <emphasis>with</emphasis> the session's
+         <varname>TimeZone</varname> value as time zone.
+        </para>
+        <para>
+         <literal>timestamp '2001-02-16 20:38:40' at local</literal>
+         <returnvalue>2001-02-17 03:38:40+00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>timestamp with time zone</type> <literal>AT TIME ZONE</literal> <replaceable>zone</replaceable>
+         <returnvalue>timestamp without time zone</returnvalue>
+        </para>
+        <para>
+         Converts given time stamp <emphasis>with</emphasis> time zone to
+         time stamp <emphasis>without</emphasis> time zone, as the time would
+         appear in that zone.
+        </para>
+        <para>
+         <literal>timestamp with time zone '2001-02-16 20:38:40-05' at time zone 'America/Denver'</literal>
+         <returnvalue>2001-02-16 18:38:40</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>timestamp with time zone</type> <literal>AT LOCAL</literal>
+         <returnvalue>timestamp without time zone</returnvalue>
+        </para>
+        <para>
+         Converts given time stamp <emphasis>with</emphasis> time zone to
+         time stamp <emphasis>without</emphasis> time zone, as the time would
+         appear with the session's <varname>TimeZone</varname> value as time zone.
+        </para>
+        <para>
+         <literal>timestamp with time zone '2001-02-16 20:38:40-05' at local</literal>
+         <returnvalue>2001-02-16 18:38:40</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>time with time zone</type> <literal>AT TIME ZONE</literal> <replaceable>zone</replaceable>
+         <returnvalue>time with time zone</returnvalue>
+        </para>
+        <para>
+         Converts given time <emphasis>with</emphasis> time zone to a new time
+         zone.  Since no date is supplied, this uses the currently active UTC
+         offset for the named destination zone.
+        </para>
+        <para>
+         <literal>time with time zone '05:34:17-05' at time zone 'UTC'</literal>
+         <returnvalue>10:34:17+00</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>time with time zone</type> <literal>AT LOCAL</literal>
+         <returnvalue>time with time zone</returnvalue>
+        </para>
+        <para>
+         Converts given time <emphasis>with</emphasis> time zone to a new time
+         zone.  Since no date is supplied, this uses the currently active UTC
+         offset for the session's <varname>TimeZone</varname> value.
+        </para>
+        <para>
+         Assuming the session's <varname>TimeZone</varname> is set to <literal>UTC</literal>:
+        </para>
+        <para>
+         <literal>time with time zone '05:34:17-05' at local</literal>
+         <returnvalue>10:34:17+00</returnvalue>
+        </para></entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+   <para>
+    In these expressions, the desired time zone <replaceable>zone</replaceable> can be
+    specified either as a text value (e.g., <literal>'America/Los_Angeles'</literal>)
+    or as an interval (e.g., <literal>INTERVAL '-08:00'</literal>).
+    In the text case, a time zone name can be specified in any of the ways
+    described in <xref linkend="datatype-timezones"/>.
+    The interval case is only useful for zones that have fixed offsets from
+    UTC, so it is not very common in practice.
+   </para>
+
+   <para>
+    The syntax <literal>AT LOCAL</literal> may be used as shorthand for
+    <literal>AT TIME ZONE <replaceable>local</replaceable></literal>, where
+    <replaceable>local</replaceable> is the session's
+    <varname>TimeZone</varname> value.
+   </para>
+
+   <para>
+    Examples (assuming the current <xref linkend="guc-timezone"/> setting
+    is <literal>America/Los_Angeles</literal>):
+<screen>
+SELECT TIMESTAMP '2001-02-16 20:38:40' AT TIME ZONE 'America/Denver';
+<lineannotation>Result: </lineannotation><computeroutput>2001-02-16 19:38:40-08</computeroutput>
+SELECT TIMESTAMP WITH TIME ZONE '2001-02-16 20:38:40-05' AT TIME ZONE 'America/Denver';
+<lineannotation>Result: </lineannotation><computeroutput>2001-02-16 18:38:40</computeroutput>
+SELECT TIMESTAMP '2001-02-16 20:38:40' AT TIME ZONE 'Asia/Tokyo' AT TIME ZONE 'America/Chicago';
+<lineannotation>Result: </lineannotation><computeroutput>2001-02-16 05:38:40</computeroutput>
+SELECT TIMESTAMP WITH TIME ZONE '2001-02-16 20:38:40-05' AT LOCAL;
+<lineannotation>Result: </lineannotation><computeroutput>2001-02-16 17:38:40</computeroutput>
+SELECT TIMESTAMP WITH TIME ZONE '2001-02-16 20:38:40-05' AT TIME ZONE '+05';
+<lineannotation>Result: </lineannotation><computeroutput>2001-02-16 20:38:40</computeroutput>
+SELECT TIME WITH TIME ZONE '20:38:40-05' AT LOCAL;
+<lineannotation>Result: </lineannotation><computeroutput>17:38:40</computeroutput>
+</screen>
+    The first example adds a time zone to a value that lacks it, and
+    displays the value using the current <varname>TimeZone</varname>
+    setting.  The second example shifts the time stamp with time zone value
+    to the specified time zone, and returns the value without a time zone.
+    This allows storage and display of values different from the current
+    <varname>TimeZone</varname> setting.  The third example converts
+    Tokyo time to Chicago time.  The fourth example shifts the time stamp
+    with time zone value to the time zone currently specified by the
+    <varname>TimeZone</varname> setting and returns the value without a
+    time zone.  The fifth example demonstrates that the sign in a POSIX-style
+    time zone specification has the opposite meaning of the sign in an
+    ISO-8601 datetime literal, as described in <xref linkend="datatype-timezones"/>
+    and <xref linkend="datetime-appendix"/>.
+   </para>
+
+   <para>
+    The sixth example is a cautionary tale. Due to the fact that there is no
+    date associated with the input value, the conversion is made using the
+    current date of the session. Therefore, this static example may show a wrong
+    result depending on the time of the year it is viewed because
+    <literal>'America/Los_Angeles'</literal> observes Daylight Savings Time.
+   </para>
+
+   <para>
+    The function <literal><function>timezone</function>(<replaceable>zone</replaceable>,
+    <replaceable>timestamp</replaceable>)</literal> is equivalent to the SQL-conforming construct
+    <literal><replaceable>timestamp</replaceable> AT TIME ZONE
+    <replaceable>zone</replaceable></literal>.
+   </para>
+
+   <para>
+    The function <literal><function>timezone</function>(<replaceable>zone</replaceable>,
+    <replaceable>time</replaceable>)</literal> is equivalent to the SQL-conforming construct
+    <literal><replaceable>time</replaceable> AT TIME ZONE
+    <replaceable>zone</replaceable></literal>.
+   </para>
+
+   <para>
+    The function <literal><function>timezone</function>(<replaceable>timestamp</replaceable>)</literal>
+    is equivalent to the SQL-conforming construct <literal><replaceable>timestamp</replaceable>
+    AT LOCAL</literal>.
+   </para>
+
+   <para>
+    The function <literal><function>timezone</function>(<replaceable>time</replaceable>)</literal>
+    is equivalent to the SQL-conforming construct <literal><replaceable>time</replaceable>
+    AT LOCAL</literal>.
+   </para>
+  </sect2>
+
+  <sect2 id="functions-datetime-current">
+   <title>Current Date/Time</title>
+
+   <indexterm>
+    <primary>date</primary>
+    <secondary>current</secondary>
+   </indexterm>
+
+   <indexterm>
+    <primary>time</primary>
+    <secondary>current</secondary>
+   </indexterm>
+
+   <para>
+    <productname>PostgreSQL</productname> provides a number of functions
+    that return values related to the current date and time.  These
+    SQL-standard functions all return values based on the start time of
+    the current transaction:
+<synopsis>
+CURRENT_DATE
+CURRENT_TIME
+CURRENT_TIMESTAMP
+CURRENT_TIME(<replaceable>precision</replaceable>)
+CURRENT_TIMESTAMP(<replaceable>precision</replaceable>)
+LOCALTIME
+LOCALTIMESTAMP
+LOCALTIME(<replaceable>precision</replaceable>)
+LOCALTIMESTAMP(<replaceable>precision</replaceable>)
+</synopsis>
+    </para>
+
+    <para>
+     <function>CURRENT_TIME</function> and
+     <function>CURRENT_TIMESTAMP</function> deliver values with time zone;
+     <function>LOCALTIME</function> and
+     <function>LOCALTIMESTAMP</function> deliver values without time zone.
+    </para>
+
+    <para>
+     <function>CURRENT_TIME</function>,
+     <function>CURRENT_TIMESTAMP</function>,
+     <function>LOCALTIME</function>, and
+     <function>LOCALTIMESTAMP</function>
+     can optionally take
+     a precision parameter, which causes the result to be rounded
+     to that many fractional digits in the seconds field.  Without a precision parameter,
+     the result is given to the full available precision.
+    </para>
+
+   <para>
+    Some examples:
+<screen>
+SELECT CURRENT_TIME;
+<lineannotation>Result: </lineannotation><computeroutput>14:39:53.662522-05</computeroutput>
+SELECT CURRENT_DATE;
+<lineannotation>Result: </lineannotation><computeroutput>2019-12-23</computeroutput>
+SELECT CURRENT_TIMESTAMP;
+<lineannotation>Result: </lineannotation><computeroutput>2019-12-23 14:39:53.662522-05</computeroutput>
+SELECT CURRENT_TIMESTAMP(2);
+<lineannotation>Result: </lineannotation><computeroutput>2019-12-23 14:39:53.66-05</computeroutput>
+SELECT LOCALTIMESTAMP;
+<lineannotation>Result: </lineannotation><computeroutput>2019-12-23 14:39:53.662522</computeroutput>
+</screen>
+   </para>
+
+   <para>
+    Since these functions return
+    the start time of the current transaction, their values do not
+    change during the transaction. This is considered a feature:
+    the intent is to allow a single transaction to have a consistent
+    notion of the <quote>current</quote> time, so that multiple
+    modifications within the same transaction bear the same
+    time stamp.
+   </para>
+
+   <note>
+    <para>
+     Other database systems might advance these values more
+     frequently.
+    </para>
+   </note>
+
+   <para>
+    <productname>PostgreSQL</productname> also provides functions that
+    return the start time of the current statement, as well as the actual
+    current time at the instant the function is called.  The complete list
+    of non-SQL-standard time functions is:
+<synopsis>
+transaction_timestamp()
+statement_timestamp()
+clock_timestamp()
+timeofday()
+now()
+</synopsis>
+   </para>
+
+   <para>
+    <function>transaction_timestamp()</function> is equivalent to
+    <function>CURRENT_TIMESTAMP</function>, but is named to clearly reflect
+    what it returns.
+    <function>statement_timestamp()</function> returns the start time of the current
+    statement (more specifically, the time of receipt of the latest command
+    message from the client).
+    <function>statement_timestamp()</function> and <function>transaction_timestamp()</function>
+    return the same value during the first statement of a transaction, but might
+    differ during subsequent statements.
+    <function>clock_timestamp()</function> returns the actual current time, and
+    therefore its value changes even within a single SQL statement.
+    <function>timeofday()</function> is a historical
+    <productname>PostgreSQL</productname> function.  Like
+    <function>clock_timestamp()</function>, it returns the actual current time,
+    but as a formatted <type>text</type> string rather than a <type>timestamp
+    with time zone</type> value.
+    <function>now()</function> is a traditional <productname>PostgreSQL</productname>
+    equivalent to <function>transaction_timestamp()</function>.
+   </para>
+
+   <para>
+    All the date/time data types also accept the special literal value
+    <literal>now</literal> to specify the current date and time (again,
+    interpreted as the transaction start time).  Thus,
+    the following three all return the same result:
+<programlisting>
+SELECT CURRENT_TIMESTAMP;
+SELECT now();
+SELECT TIMESTAMP 'now';  -- but see tip below
+</programlisting>
+   </para>
+
+    <tip>
+     <para>
+      Do not use the third form when specifying a value to be evaluated later,
+      for example in a <literal>DEFAULT</literal> clause for a table column.
+      The system will convert <literal>now</literal>
+      to a <type>timestamp</type> as soon as the constant is parsed, so that when
+      the default value is needed,
+      the time of the table creation would be used!  The first two
+      forms will not be evaluated until the default value is used,
+      because they are function calls.  Thus they will give the desired
+      behavior of defaulting to the time of row insertion.
+      (See also <xref linkend="datatype-datetime-special-values"/>.)
+     </para>
+    </tip>
+  </sect2>
+
+  <sect2 id="functions-datetime-delay">
+   <title>Delaying Execution</title>
+
+   <indexterm>
+    <primary>pg_sleep</primary>
+   </indexterm>
+   <indexterm>
+    <primary>pg_sleep_for</primary>
+   </indexterm>
+   <indexterm>
+    <primary>pg_sleep_until</primary>
+   </indexterm>
+   <indexterm>
+    <primary>sleep</primary>
+   </indexterm>
+   <indexterm>
+    <primary>delay</primary>
+   </indexterm>
+
+   <para>
+    The following functions are available to delay execution of the server
+    process:
+<synopsis>
+pg_sleep ( <type>double precision</type> )
+pg_sleep_for ( <type>interval</type> )
+pg_sleep_until ( <type>timestamp with time zone</type> )
+</synopsis>
+
+    <function>pg_sleep</function> makes the current session's process
+    sleep until the given number of seconds have
+    elapsed.  Fractional-second delays can be specified.
+    <function>pg_sleep_for</function> is a convenience function to
+    allow the sleep time to be specified as an <type>interval</type>.
+    <function>pg_sleep_until</function> is a convenience function for when
+    a specific wake-up time is desired.
+    For example:
+
+<programlisting>
+SELECT pg_sleep(1.5);
+SELECT pg_sleep_for('5 minutes');
+SELECT pg_sleep_until('tomorrow 03:00');
+</programlisting>
+   </para>
+
+   <note>
+     <para>
+      The effective resolution of the sleep interval is platform-specific;
+      0.01 seconds is a common value.  The sleep delay will be at least as long
+      as specified. It might be longer depending on factors such as server load.
+      In particular, <function>pg_sleep_until</function> is not guaranteed to
+      wake up exactly at the specified time, but it will not wake up any earlier.
+     </para>
+   </note>
+
+   <warning>
+     <para>
+      Make sure that your session does not hold more locks than necessary
+      when calling <function>pg_sleep</function> or its variants.  Otherwise
+      other sessions might have to wait for your sleeping process, slowing down
+      the entire system.
+     </para>
+   </warning>
+  </sect2>
+
+ </sect1>
diff --git a/doc/src/sgml/func/func-enum.sgml b/doc/src/sgml/func/func-enum.sgml
new file mode 100644
index 0000000000000..6227afe4057ba
--- /dev/null
+++ b/doc/src/sgml/func/func-enum.sgml
@@ -0,0 +1,121 @@
+ <sect1 id="functions-enum">
+  <title>Enum Support Functions</title>
+
+  <para>
+   For enum types (described in <xref linkend="datatype-enum"/>),
+   there are several functions that allow cleaner programming without
+   hard-coding particular values of an enum type.
+   These are listed in <xref linkend="functions-enum-table"/>. The examples
+   assume an enum type created as:
+
+<programlisting>
+CREATE TYPE rainbow AS ENUM ('red', 'orange', 'yellow', 'green', 'blue', 'purple');
+</programlisting>
+
+  </para>
+
+  <table id="functions-enum-table">
+    <title>Enum Support Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>enum_first</primary>
+        </indexterm>
+        <function>enum_first</function> ( <type>anyenum</type> )
+        <returnvalue>anyenum</returnvalue>
+       </para>
+       <para>
+        Returns the first value of the input enum type.
+       </para>
+       <para>
+        <literal>enum_first(null::rainbow)</literal>
+        <returnvalue>red</returnvalue>
+       </para></entry>
+      </row>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>enum_last</primary>
+        </indexterm>
+        <function>enum_last</function> ( <type>anyenum</type> )
+        <returnvalue>anyenum</returnvalue>
+       </para>
+       <para>
+        Returns the last value of the input enum type.
+       </para>
+       <para>
+        <literal>enum_last(null::rainbow)</literal>
+        <returnvalue>purple</returnvalue>
+       </para></entry>
+      </row>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>enum_range</primary>
+        </indexterm>
+        <function>enum_range</function> ( <type>anyenum</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Returns all values of the input enum type in an ordered array.
+       </para>
+       <para>
+        <literal>enum_range(null::rainbow)</literal>
+        <returnvalue>{red,orange,yellow,&zwsp;green,blue,purple}</returnvalue>
+       </para></entry>
+      </row>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>enum_range</function> ( <type>anyenum</type>, <type>anyenum</type> )
+        <returnvalue>anyarray</returnvalue>
+       </para>
+       <para>
+        Returns the range between the two given enum values, as an ordered
+        array. The values must be from the same enum type. If the first
+        parameter is null, the result will start with the first value of
+        the enum type.
+        If the second parameter is null, the result will end with the last
+        value of the enum type.
+       </para>
+       <para>
+        <literal>enum_range('orange'::rainbow, 'green'::rainbow)</literal>
+        <returnvalue>{orange,yellow,green}</returnvalue>
+       </para>
+       <para>
+        <literal>enum_range(NULL, 'green'::rainbow)</literal>
+        <returnvalue>{red,orange,&zwsp;yellow,green}</returnvalue>
+       </para>
+       <para>
+        <literal>enum_range('orange'::rainbow, NULL)</literal>
+        <returnvalue>{orange,yellow,green,&zwsp;blue,purple}</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    Notice that except for the two-argument form of <function>enum_range</function>,
+    these functions disregard the specific value passed to them; they care
+    only about its declared data type.  Either null or a specific value of
+    the type can be passed, with the same result.  It is more common to
+    apply these functions to a table column or function argument than to
+    a hardwired type name as used in the examples.
+   </para>
+ </sect1>
diff --git a/doc/src/sgml/func/func-event-triggers.sgml b/doc/src/sgml/func/func-event-triggers.sgml
new file mode 100644
index 0000000000000..9f3f51e9f5133
--- /dev/null
+++ b/doc/src/sgml/func/func-event-triggers.sgml
@@ -0,0 +1,332 @@
+  <sect1 id="functions-event-triggers">
+   <title>Event Trigger Functions</title>
+
+   <para>
+    <productname>PostgreSQL</productname> provides these helper functions
+    to retrieve information from event triggers.
+   </para>
+
+   <para>
+    For more information about event triggers,
+    see <xref linkend="event-triggers"/>.
+   </para>
+
+  <sect2 id="pg-event-trigger-ddl-command-end-functions">
+   <title>Capturing Changes at Command End</title>
+
+   <indexterm>
+    <primary>pg_event_trigger_ddl_commands</primary>
+   </indexterm>
+
+<synopsis>
+<function>pg_event_trigger_ddl_commands</function> () <returnvalue>setof record</returnvalue>
+</synopsis>
+
+   <para>
+    <function>pg_event_trigger_ddl_commands</function> returns a list of
+    <acronym>DDL</acronym> commands executed by each user action,
+    when invoked in a function attached to a
+    <literal>ddl_command_end</literal> event trigger.  If called in any other
+    context, an error is raised.
+    <function>pg_event_trigger_ddl_commands</function> returns one row for each
+    base command executed; some commands that are a single SQL sentence
+    may return more than one row.  This function returns the following
+    columns:
+
+    <informaltable>
+     <tgroup cols="3">
+      <thead>
+       <row>
+        <entry>Name</entry>
+        <entry>Type</entry>
+        <entry>Description</entry>
+       </row>
+      </thead>
+
+      <tbody>
+       <row>
+        <entry><literal>classid</literal></entry>
+        <entry><type>oid</type></entry>
+        <entry>OID of catalog the object belongs in</entry>
+       </row>
+       <row>
+        <entry><literal>objid</literal></entry>
+        <entry><type>oid</type></entry>
+        <entry>OID of the object itself</entry>
+       </row>
+       <row>
+        <entry><literal>objsubid</literal></entry>
+        <entry><type>integer</type></entry>
+        <entry>Sub-object ID (e.g., attribute number for a column)</entry>
+       </row>
+       <row>
+        <entry><literal>command_tag</literal></entry>
+        <entry><type>text</type></entry>
+        <entry>Command tag</entry>
+       </row>
+       <row>
+        <entry><literal>object_type</literal></entry>
+        <entry><type>text</type></entry>
+        <entry>Type of the object</entry>
+       </row>
+       <row>
+        <entry><literal>schema_name</literal></entry>
+        <entry><type>text</type></entry>
+        <entry>
+         Name of the schema the object belongs in, if any; otherwise <literal>NULL</literal>.
+         No quoting is applied.
+        </entry>
+       </row>
+       <row>
+        <entry><literal>object_identity</literal></entry>
+        <entry><type>text</type></entry>
+        <entry>
+         Text rendering of the object identity, schema-qualified. Each
+         identifier included in the identity is quoted if necessary.
+        </entry>
+       </row>
+       <row>
+        <entry><literal>in_extension</literal></entry>
+        <entry><type>boolean</type></entry>
+        <entry>True if the command is part of an extension script</entry>
+       </row>
+       <row>
+        <entry><literal>command</literal></entry>
+        <entry><type>pg_ddl_command</type></entry>
+        <entry>
+         A complete representation of the command, in internal format.
+         This cannot be output directly, but it can be passed to other
+         functions to obtain different pieces of information about the
+         command.
+        </entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </informaltable>
+   </para>
+  </sect2>
+
+  <sect2 id="pg-event-trigger-sql-drop-functions">
+   <title>Processing Objects Dropped by a DDL Command</title>
+
+   <indexterm>
+     <primary>pg_event_trigger_dropped_objects</primary>
+   </indexterm>
+
+<synopsis>
+<function>pg_event_trigger_dropped_objects</function> () <returnvalue>setof record</returnvalue>
+</synopsis>
+
+   <para>
+    <function>pg_event_trigger_dropped_objects</function> returns a list of all objects
+    dropped by the command in whose <literal>sql_drop</literal> event it is called.
+    If called in any other context, an error is raised.
+    This function returns the following columns:
+
+    <informaltable>
+     <tgroup cols="3">
+      <thead>
+       <row>
+        <entry>Name</entry>
+        <entry>Type</entry>
+        <entry>Description</entry>
+       </row>
+      </thead>
+
+      <tbody>
+       <row>
+        <entry><literal>classid</literal></entry>
+        <entry><type>oid</type></entry>
+        <entry>OID of catalog the object belonged in</entry>
+       </row>
+       <row>
+        <entry><literal>objid</literal></entry>
+        <entry><type>oid</type></entry>
+        <entry>OID of the object itself</entry>
+       </row>
+       <row>
+        <entry><literal>objsubid</literal></entry>
+        <entry><type>integer</type></entry>
+        <entry>Sub-object ID (e.g., attribute number for a column)</entry>
+       </row>
+       <row>
+        <entry><literal>original</literal></entry>
+        <entry><type>boolean</type></entry>
+        <entry>True if this was one of the root object(s) of the deletion</entry>
+       </row>
+       <row>
+        <entry><literal>normal</literal></entry>
+        <entry><type>boolean</type></entry>
+        <entry>
+         True if there was a normal dependency relationship
+         in the dependency graph leading to this object
+        </entry>
+       </row>
+       <row>
+        <entry><literal>is_temporary</literal></entry>
+        <entry><type>boolean</type></entry>
+        <entry>
+         True if this was a temporary object
+        </entry>
+       </row>
+       <row>
+        <entry><literal>object_type</literal></entry>
+        <entry><type>text</type></entry>
+        <entry>Type of the object</entry>
+       </row>
+       <row>
+        <entry><literal>schema_name</literal></entry>
+        <entry><type>text</type></entry>
+        <entry>
+         Name of the schema the object belonged in, if any; otherwise <literal>NULL</literal>.
+         No quoting is applied.
+        </entry>
+       </row>
+       <row>
+        <entry><literal>object_name</literal></entry>
+        <entry><type>text</type></entry>
+        <entry>
+         Name of the object, if the combination of schema and name can be
+         used as a unique identifier for the object; otherwise <literal>NULL</literal>.
+         No quoting is applied, and name is never schema-qualified.
+        </entry>
+       </row>
+       <row>
+        <entry><literal>object_identity</literal></entry>
+        <entry><type>text</type></entry>
+        <entry>
+         Text rendering of the object identity, schema-qualified. Each
+         identifier included in the identity is quoted if necessary.
+        </entry>
+       </row>
+       <row>
+        <entry><literal>address_names</literal></entry>
+        <entry><type>text[]</type></entry>
+        <entry>
+         An array that, together with <literal>object_type</literal> and
+         <literal>address_args</literal>, can be used by
+         the <function>pg_get_object_address</function> function to
+         recreate the object address in a remote server containing an
+         identically named object of the same kind.
+        </entry>
+       </row>
+       <row>
+        <entry><literal>address_args</literal></entry>
+        <entry><type>text[]</type></entry>
+        <entry>
+         Complement for <literal>address_names</literal>
+        </entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </informaltable>
+   </para>
+
+   <para>
+    The <function>pg_event_trigger_dropped_objects</function> function can be used
+    in an event trigger like this:
+<programlisting>
+CREATE FUNCTION test_event_trigger_for_drops()
+        RETURNS event_trigger LANGUAGE plpgsql AS $$
+DECLARE
+    obj record;
+BEGIN
+    FOR obj IN SELECT * FROM pg_event_trigger_dropped_objects()
+    LOOP
+        RAISE NOTICE '% dropped object: % %.% %',
+                     tg_tag,
+                     obj.object_type,
+                     obj.schema_name,
+                     obj.object_name,
+                     obj.object_identity;
+    END LOOP;
+END;
+$$;
+CREATE EVENT TRIGGER test_event_trigger_for_drops
+   ON sql_drop
+   EXECUTE FUNCTION test_event_trigger_for_drops();
+</programlisting>
+    </para>
+  </sect2>
+
+  <sect2 id="pg-event-trigger-table-rewrite-functions">
+   <title>Handling a Table Rewrite Event</title>
+
+   <para>
+    The functions shown in
+    <xref linkend="functions-event-trigger-table-rewrite"/>
+    provide information about a table for which a
+    <literal>table_rewrite</literal> event has just been called.
+    If called in any other context, an error is raised.
+   </para>
+
+   <table id="functions-event-trigger-table-rewrite">
+    <title>Table Rewrite Information Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_event_trigger_table_rewrite_oid</primary>
+        </indexterm>
+        <function>pg_event_trigger_table_rewrite_oid</function> ()
+        <returnvalue>oid</returnvalue>
+       </para>
+       <para>
+        Returns the OID of the table about to be rewritten.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_event_trigger_table_rewrite_reason</primary>
+        </indexterm>
+        <function>pg_event_trigger_table_rewrite_reason</function> ()
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns a code explaining the reason(s) for rewriting. The value is
+        a bitmap built from the following values: <literal>1</literal>
+        (the table has changed its persistence), <literal>2</literal>
+        (default value of a column has changed), <literal>4</literal>
+        (a column has a new data type) and <literal>8</literal>
+        (the table access method has changed).
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    These functions can be used in an event trigger like this:
+<programlisting>
+CREATE FUNCTION test_event_trigger_table_rewrite_oid()
+ RETURNS event_trigger
+ LANGUAGE plpgsql AS
+$$
+BEGIN
+  RAISE NOTICE 'rewriting table % for reason %',
+                pg_event_trigger_table_rewrite_oid()::regclass,
+                pg_event_trigger_table_rewrite_reason();
+END;
+$$;
+
+CREATE EVENT TRIGGER test_table_rewrite_oid
+                  ON table_rewrite
+   EXECUTE FUNCTION test_event_trigger_table_rewrite_oid();
+</programlisting>
+    </para>
+  </sect2>
+  </sect1>
diff --git a/doc/src/sgml/func/func-formatting.sgml b/doc/src/sgml/func/func-formatting.sgml
new file mode 100644
index 0000000000000..806302b2f7b34
--- /dev/null
+++ b/doc/src/sgml/func/func-formatting.sgml
@@ -0,0 +1,1193 @@
+  <sect1 id="functions-formatting">
+   <title>Data Type Formatting Functions</title>
+
+   <indexterm>
+    <primary>formatting</primary>
+   </indexterm>
+
+   <para>
+    The <productname>PostgreSQL</productname> formatting functions
+    provide a powerful set of tools for converting various data types
+    (date/time, integer, floating point, numeric) to formatted strings
+    and for converting from formatted strings to specific data types.
+    <xref linkend="functions-formatting-table"/> lists them.
+    These functions all follow a common calling convention: the first
+    argument is the value to be formatted and the second argument is a
+    template that defines the output or input format.
+   </para>
+
+   <table id="functions-formatting-table">
+    <title>Formatting Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_char</primary>
+        </indexterm>
+        <function>to_char</function> ( <type>timestamp</type>, <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>to_char</function> ( <type>timestamp with time zone</type>, <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts time stamp to string according to the given format.
+       </para>
+       <para>
+        <literal>to_char(timestamp '2002-04-20 17:31:12.66', 'HH12:MI:SS')</literal>
+        <returnvalue>05:31:12</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>to_char</function> ( <type>interval</type>, <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts interval to string according to the given format.
+       </para>
+       <para>
+       <literal>to_char(interval '15h 2m 12s', 'HH24:MI:SS')</literal>
+       <returnvalue>15:02:12</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>to_char</function> ( <replaceable>numeric_type</replaceable>, <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts number to string according to the given format; available
+        for <type>integer</type>, <type>bigint</type>, <type>numeric</type>,
+        <type>real</type>, <type>double precision</type>.
+       </para>
+       <para>
+        <literal>to_char(125, '999')</literal>
+        <returnvalue>125</returnvalue>
+       </para>
+       <para>
+        <literal>to_char(125.8::real, '999D9')</literal>
+        <returnvalue>125.8</returnvalue>
+       </para>
+       <para>
+        <literal>to_char(-125.8, '999D99S')</literal>
+        <returnvalue>125.80-</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_date</primary>
+        </indexterm>
+        <function>to_date</function> ( <type>text</type>, <type>text</type> )
+        <returnvalue>date</returnvalue>
+       </para>
+       <para>
+        Converts string to date according to the given format.
+       </para>
+       <para>
+        <literal>to_date('05 Dec 2000', 'DD Mon YYYY')</literal>
+        <returnvalue>2000-12-05</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_number</primary>
+        </indexterm>
+        <function>to_number</function> ( <type>text</type>, <type>text</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para>
+        Converts string to numeric according to the given format.
+       </para>
+       <para>
+        <literal>to_number('12,454.8-', '99G999D9S')</literal>
+        <returnvalue>-12454.8</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_timestamp</primary>
+        </indexterm>
+        <function>to_timestamp</function> ( <type>text</type>, <type>text</type> )
+        <returnvalue>timestamp with time zone</returnvalue>
+       </para>
+       <para>
+        Converts string to time stamp according to the given format.
+        (See also <function>to_timestamp(double precision)</function> in
+        <xref linkend="functions-datetime-table"/>.)
+       </para>
+       <para>
+        <literal>to_timestamp('05 Dec 2000', 'DD Mon YYYY')</literal>
+        <returnvalue>2000-12-05 00:00:00-05</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <tip>
+    <para>
+     <function>to_timestamp</function> and <function>to_date</function>
+     exist to handle input formats that cannot be converted by
+     simple casting.  For most standard date/time formats, simply casting the
+     source string to the required data type works, and is much easier.
+     Similarly, <function>to_number</function> is unnecessary for standard numeric
+     representations.
+    </para>
+   </tip>
+
+   <para>
+    In a <function>to_char</function> output template string, there are certain
+    patterns that are recognized and replaced with appropriately-formatted
+    data based on the given value.  Any text that is not a template pattern is
+    simply copied verbatim.  Similarly, in an input template string (for the
+    other functions), template patterns identify the values to be supplied by
+    the input data string.  If there are characters in the template string
+    that are not template patterns, the corresponding characters in the input
+    data string are simply skipped over (whether or not they are equal to the
+    template string characters).
+   </para>
+
+  <para>
+   <xref linkend="functions-formatting-datetime-table"/> shows the
+   template patterns available for formatting date and time values.
+  </para>
+
+    <table id="functions-formatting-datetime-table">
+     <title>Template Patterns for Date/Time Formatting</title>
+     <tgroup cols="2">
+      <thead>
+       <row>
+        <entry>Pattern</entry>
+        <entry>Description</entry>
+       </row>
+      </thead>
+      <tbody>
+       <row>
+        <entry><literal>HH</literal></entry>
+        <entry>hour of day (01&ndash;12)</entry>
+       </row>
+       <row>
+        <entry><literal>HH12</literal></entry>
+        <entry>hour of day (01&ndash;12)</entry>
+       </row>
+       <row>
+        <entry><literal>HH24</literal></entry>
+        <entry>hour of day (00&ndash;23)</entry>
+       </row>
+       <row>
+        <entry><literal>MI</literal></entry>
+        <entry>minute (00&ndash;59)</entry>
+       </row>
+       <row>
+        <entry><literal>SS</literal></entry>
+        <entry>second (00&ndash;59)</entry>
+       </row>
+       <row>
+        <entry><literal>MS</literal></entry>
+        <entry>millisecond (000&ndash;999)</entry>
+       </row>
+       <row>
+        <entry><literal>US</literal></entry>
+        <entry>microsecond (000000&ndash;999999)</entry>
+       </row>
+       <row>
+        <entry><literal>FF1</literal></entry>
+        <entry>tenth of second (0&ndash;9)</entry>
+       </row>
+       <row>
+        <entry><literal>FF2</literal></entry>
+        <entry>hundredth of second (00&ndash;99)</entry>
+       </row>
+       <row>
+        <entry><literal>FF3</literal></entry>
+        <entry>millisecond (000&ndash;999)</entry>
+       </row>
+       <row>
+        <entry><literal>FF4</literal></entry>
+        <entry>tenth of a millisecond (0000&ndash;9999)</entry>
+       </row>
+       <row>
+        <entry><literal>FF5</literal></entry>
+        <entry>hundredth of a millisecond (00000&ndash;99999)</entry>
+       </row>
+       <row>
+        <entry><literal>FF6</literal></entry>
+        <entry>microsecond (000000&ndash;999999)</entry>
+       </row>
+       <row>
+        <entry><literal>SSSS</literal>, <literal>SSSSS</literal></entry>
+        <entry>seconds past midnight (0&ndash;86399)</entry>
+       </row>
+       <row>
+        <entry><literal>AM</literal>, <literal>am</literal>,
+        <literal>PM</literal> or <literal>pm</literal></entry>
+        <entry>meridiem indicator (without periods)</entry>
+       </row>
+       <row>
+        <entry><literal>A.M.</literal>, <literal>a.m.</literal>,
+        <literal>P.M.</literal> or <literal>p.m.</literal></entry>
+        <entry>meridiem indicator (with periods)</entry>
+       </row>
+       <row>
+        <entry><literal>Y,YYY</literal></entry>
+        <entry>year (4 or more digits) with comma</entry>
+       </row>
+       <row>
+        <entry><literal>YYYY</literal></entry>
+        <entry>year (4 or more digits)</entry>
+       </row>
+       <row>
+        <entry><literal>YYY</literal></entry>
+        <entry>last 3 digits of year</entry>
+       </row>
+       <row>
+        <entry><literal>YY</literal></entry>
+        <entry>last 2 digits of year</entry>
+       </row>
+       <row>
+        <entry><literal>Y</literal></entry>
+        <entry>last digit of year</entry>
+       </row>
+       <row>
+        <entry><literal>IYYY</literal></entry>
+        <entry>ISO 8601 week-numbering year (4 or more digits)</entry>
+       </row>
+       <row>
+        <entry><literal>IYY</literal></entry>
+        <entry>last 3 digits of ISO 8601 week-numbering year</entry>
+       </row>
+       <row>
+        <entry><literal>IY</literal></entry>
+        <entry>last 2 digits of ISO 8601 week-numbering year</entry>
+       </row>
+       <row>
+        <entry><literal>I</literal></entry>
+        <entry>last digit of ISO 8601 week-numbering year</entry>
+       </row>
+       <row>
+        <entry><literal>BC</literal>, <literal>bc</literal>,
+        <literal>AD</literal> or <literal>ad</literal></entry>
+        <entry>era indicator (without periods)</entry>
+       </row>
+       <row>
+        <entry><literal>B.C.</literal>, <literal>b.c.</literal>,
+        <literal>A.D.</literal> or <literal>a.d.</literal></entry>
+        <entry>era indicator (with periods)</entry>
+       </row>
+       <row>
+        <entry><literal>MONTH</literal></entry>
+        <entry>full upper case month name (blank-padded to 9 chars)</entry>
+       </row>
+       <row>
+        <entry><literal>Month</literal></entry>
+        <entry>full capitalized month name (blank-padded to 9 chars)</entry>
+       </row>
+       <row>
+        <entry><literal>month</literal></entry>
+        <entry>full lower case month name (blank-padded to 9 chars)</entry>
+       </row>
+       <row>
+        <entry><literal>MON</literal></entry>
+        <entry>abbreviated upper case month name (3 chars in English, localized lengths vary)</entry>
+       </row>
+       <row>
+        <entry><literal>Mon</literal></entry>
+        <entry>abbreviated capitalized month name (3 chars in English, localized lengths vary)</entry>
+       </row>
+       <row>
+        <entry><literal>mon</literal></entry>
+        <entry>abbreviated lower case month name (3 chars in English, localized lengths vary)</entry>
+       </row>
+       <row>
+        <entry><literal>MM</literal></entry>
+        <entry>month number (01&ndash;12)</entry>
+       </row>
+       <row>
+        <entry><literal>DAY</literal></entry>
+        <entry>full upper case day name (blank-padded to 9 chars)</entry>
+       </row>
+       <row>
+        <entry><literal>Day</literal></entry>
+        <entry>full capitalized day name (blank-padded to 9 chars)</entry>
+       </row>
+       <row>
+        <entry><literal>day</literal></entry>
+        <entry>full lower case day name (blank-padded to 9 chars)</entry>
+       </row>
+       <row>
+        <entry><literal>DY</literal></entry>
+        <entry>abbreviated upper case day name (3 chars in English, localized lengths vary)</entry>
+       </row>
+       <row>
+        <entry><literal>Dy</literal></entry>
+        <entry>abbreviated capitalized day name (3 chars in English, localized lengths vary)</entry>
+       </row>
+       <row>
+        <entry><literal>dy</literal></entry>
+        <entry>abbreviated lower case day name (3 chars in English, localized lengths vary)</entry>
+       </row>
+       <row>
+        <entry><literal>DDD</literal></entry>
+        <entry>day of year (001&ndash;366)</entry>
+       </row>
+       <row>
+        <entry><literal>IDDD</literal></entry>
+        <entry>day of ISO 8601 week-numbering year (001&ndash;371; day 1 of the year is Monday of the first ISO week)</entry>
+       </row>
+       <row>
+        <entry><literal>DD</literal></entry>
+        <entry>day of month (01&ndash;31)</entry>
+       </row>
+       <row>
+        <entry><literal>D</literal></entry>
+        <entry>day of the week, Sunday (<literal>1</literal>) to Saturday (<literal>7</literal>)</entry>
+       </row>
+       <row>
+        <entry><literal>ID</literal></entry>
+        <entry>ISO 8601 day of the week, Monday (<literal>1</literal>) to Sunday (<literal>7</literal>)</entry>
+       </row>
+       <row>
+        <entry><literal>W</literal></entry>
+        <entry>week of month (1&ndash;5) (the first week starts on the first day of the month)</entry>
+       </row>
+       <row>
+        <entry><literal>WW</literal></entry>
+        <entry>week number of year (1&ndash;53) (the first week starts on the first day of the year)</entry>
+       </row>
+       <row>
+        <entry><literal>IW</literal></entry>
+        <entry>week number of ISO 8601 week-numbering year (01&ndash;53; the first Thursday of the year is in week 1)</entry>
+       </row>
+       <row>
+        <entry><literal>CC</literal></entry>
+        <entry>century (2 digits) (the twenty-first century starts on 2001-01-01)</entry>
+       </row>
+       <row>
+        <entry><literal>J</literal></entry>
+        <entry>Julian Date (integer days since November 24, 4714 BC at local
+        midnight; see <xref linkend="datetime-julian-dates"/>)</entry>
+       </row>
+       <row>
+        <entry><literal>Q</literal></entry>
+        <entry>quarter</entry>
+       </row>
+       <row>
+        <entry><literal>RM</literal></entry>
+        <entry>month in upper case Roman numerals (I&ndash;XII; I=January)</entry>
+       </row>
+       <row>
+        <entry><literal>rm</literal></entry>
+        <entry>month in lower case Roman numerals (i&ndash;xii; i=January)</entry>
+       </row>
+       <row>
+        <entry><literal>TZ</literal></entry>
+        <entry>upper case time-zone abbreviation</entry>
+       </row>
+       <row>
+        <entry><literal>tz</literal></entry>
+        <entry>lower case time-zone abbreviation</entry>
+       </row>
+       <row>
+       <entry><literal>TZH</literal></entry>
+        <entry>time-zone hours</entry>
+       </row>
+       <row>
+       <entry><literal>TZM</literal></entry>
+        <entry>time-zone minutes</entry>
+       </row>
+       <row>
+        <entry><literal>OF</literal></entry>
+        <entry>time-zone offset from UTC (<replaceable>HH</replaceable>
+         or <replaceable>HH</replaceable><literal>:</literal><replaceable>MM</replaceable>)</entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+   <para>
+    Modifiers can be applied to any template pattern to alter its
+    behavior.  For example, <literal>FMMonth</literal>
+    is the <literal>Month</literal> pattern with the
+    <literal>FM</literal> modifier.
+    <xref linkend="functions-formatting-datetimemod-table"/> shows the
+    modifier patterns for date/time formatting.
+   </para>
+
+    <table id="functions-formatting-datetimemod-table">
+     <title>Template Pattern Modifiers for Date/Time Formatting</title>
+     <tgroup cols="3">
+      <thead>
+       <row>
+        <entry>Modifier</entry>
+        <entry>Description</entry>
+        <entry>Example</entry>
+       </row>
+      </thead>
+      <tbody>
+       <row>
+        <entry><literal>FM</literal> prefix</entry>
+        <entry>fill mode (suppress leading zeroes and padding blanks)</entry>
+        <entry><literal>FMMonth</literal></entry>
+       </row>
+       <row>
+        <entry><literal>TH</literal> suffix</entry>
+        <entry>upper case ordinal number suffix</entry>
+        <entry><literal>DDTH</literal>, e.g., <literal>12TH</literal></entry>
+       </row>
+       <row>
+        <entry><literal>th</literal> suffix</entry>
+        <entry>lower case ordinal number suffix</entry>
+        <entry><literal>DDth</literal>, e.g., <literal>12th</literal></entry>
+       </row>
+       <row>
+        <entry><literal>FX</literal> prefix</entry>
+        <entry>fixed format global option (see usage notes)</entry>
+        <entry><literal>FX&nbsp;Month&nbsp;DD&nbsp;Day</literal></entry>
+       </row>
+       <row>
+        <entry><literal>TM</literal> prefix</entry>
+        <entry>translation mode (use localized day and month names based on
+         <xref linkend="guc-lc-time"/>)</entry>
+        <entry><literal>TMMonth</literal></entry>
+       </row>
+       <row>
+        <entry><literal>SP</literal> suffix</entry>
+        <entry>spell mode (not implemented)</entry>
+        <entry><literal>DDSP</literal></entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+   <para>
+    Usage notes for date/time formatting:
+
+    <itemizedlist>
+     <listitem>
+      <para>
+       <literal>FM</literal> suppresses leading zeroes and trailing blanks
+       that would otherwise be added to make the output of a pattern be
+       fixed-width.  In <productname>PostgreSQL</productname>,
+       <literal>FM</literal> modifies only the next specification, while in
+       Oracle <literal>FM</literal> affects all subsequent
+       specifications, and repeated <literal>FM</literal> modifiers
+       toggle fill mode on and off.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       <literal>TM</literal> suppresses trailing blanks whether or
+       not <literal>FM</literal> is specified.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       <function>to_timestamp</function> and <function>to_date</function>
+       ignore letter case in the input; so for
+       example <literal>MON</literal>, <literal>Mon</literal>,
+       and <literal>mon</literal> all accept the same strings.  When using
+       the <literal>TM</literal> modifier, case-folding is done according to
+       the rules of the function's input collation (see
+       <xref linkend="collation"/>).
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       <function>to_timestamp</function> and <function>to_date</function>
+       skip multiple blank spaces at the beginning of the input string and
+       around date and time values unless the <literal>FX</literal> option is used.  For example,
+       <literal>to_timestamp('&nbsp;2000&nbsp;&nbsp;&nbsp;&nbsp;JUN', 'YYYY MON')</literal> and
+       <literal>to_timestamp('2000 - JUN', 'YYYY-MON')</literal> work, but
+       <literal>to_timestamp('2000&nbsp;&nbsp;&nbsp;&nbsp;JUN', 'FXYYYY MON')</literal> returns an error
+       because <function>to_timestamp</function> expects only a single space.
+       <literal>FX</literal> must be specified as the first item in
+       the template.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       A separator (a space or non-letter/non-digit character) in the template string of
+       <function>to_timestamp</function> and <function>to_date</function>
+       matches any single separator in the input string or is skipped,
+       unless the <literal>FX</literal> option is used.
+       For example, <literal>to_timestamp('2000JUN', 'YYYY///MON')</literal> and
+       <literal>to_timestamp('2000/JUN', 'YYYY MON')</literal> work, but
+       <literal>to_timestamp('2000//JUN', 'YYYY/MON')</literal>
+       returns an error because the number of separators in the input string
+       exceeds the number of separators in the template.
+      </para>
+      <para>
+       If <literal>FX</literal> is specified, a separator in the template string
+       matches exactly one character in the input string.  But note that the
+       input string character is not required to be the same as the separator from the template string.
+       For example, <literal>to_timestamp('2000/JUN', 'FXYYYY MON')</literal>
+       works, but <literal>to_timestamp('2000/JUN', 'FXYYYY&nbsp;&nbsp;MON')</literal>
+       returns an error because the second space in the template string consumes
+       the letter <literal>J</literal> from the input string.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       A <literal>TZH</literal> template pattern can match a signed number.
+       Without the <literal>FX</literal> option, minus signs may be ambiguous,
+       and could be interpreted as a separator.
+       This ambiguity is resolved as follows:  If the number of separators before
+       <literal>TZH</literal> in the template string is less than the number of
+       separators before the minus sign in the input string, the minus sign
+       is interpreted as part of <literal>TZH</literal>.
+       Otherwise, the minus sign is considered to be a separator between values.
+       For example, <literal>to_timestamp('2000 -10', 'YYYY TZH')</literal> matches
+       <literal>-10</literal> to <literal>TZH</literal>, but
+       <literal>to_timestamp('2000 -10', 'YYYY&nbsp;&nbsp;TZH')</literal>
+       matches <literal>10</literal> to <literal>TZH</literal>.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       Ordinary text is allowed in <function>to_char</function>
+       templates and will be output literally.  You can put a substring
+       in double quotes to force it to be interpreted as literal text
+       even if it contains template patterns.  For example, in
+       <literal>'"Hello Year "YYYY'</literal>, the <literal>YYYY</literal>
+       will be replaced by the year data, but the single <literal>Y</literal> in <literal>Year</literal>
+       will not be.
+       In <function>to_date</function>, <function>to_number</function>,
+       and <function>to_timestamp</function>, literal text and double-quoted
+       strings result in skipping the number of characters contained in the
+       string; for example <literal>"XX"</literal> skips two input characters
+       (whether or not they are <literal>XX</literal>).
+      </para>
+      <tip>
+        <para>
+          Prior to <productname>PostgreSQL</productname> 12, it was possible to
+          skip arbitrary text in the input string using non-letter or non-digit
+          characters. For example,
+          <literal>to_timestamp('2000y6m1d', 'yyyy-MM-DD')</literal> used to
+          work.  Now you can only use letter characters for this purpose.  For example,
+          <literal>to_timestamp('2000y6m1d', 'yyyytMMtDDt')</literal> and
+          <literal>to_timestamp('2000y6m1d', 'yyyy"y"MM"m"DD"d"')</literal>
+          skip <literal>y</literal>, <literal>m</literal>, and
+          <literal>d</literal>.
+        </para>
+      </tip>
+     </listitem>
+
+     <listitem>
+      <para>
+       If you want to have a double quote in the output you must
+       precede it with a backslash, for example <literal>'\"YYYY
+       Month\"'</literal>. <!-- "" font-lock sanity :-) -->
+       Backslashes are not otherwise special outside of double-quoted
+       strings.  Within a double-quoted string, a backslash causes the
+       next character to be taken literally, whatever it is (but this
+       has no special effect unless the next character is a double quote
+       or another backslash).
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       In <function>to_timestamp</function> and <function>to_date</function>,
+       if the year format specification is less than four digits, e.g.,
+       <literal>YYY</literal>, and the supplied year is less than four digits,
+       the year will be adjusted to be nearest to the year 2020, e.g.,
+       <literal>95</literal> becomes 1995.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       In <function>to_timestamp</function> and <function>to_date</function>,
+       negative years are treated as signifying BC.  If you write both a
+       negative year and an explicit <literal>BC</literal> field, you get AD
+       again.  An input of year zero is treated as 1 BC.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       In <function>to_timestamp</function> and <function>to_date</function>,
+       the <literal>YYYY</literal> conversion has a restriction when
+       processing years with more than 4 digits. You must
+       use some non-digit character or template after <literal>YYYY</literal>,
+       otherwise the year is always interpreted as 4 digits. For example
+       (with the year 20000):
+       <literal>to_date('200001130', 'YYYYMMDD')</literal> will be
+       interpreted as a 4-digit year; instead use a non-digit
+       separator after the year, like
+       <literal>to_date('20000-1130', 'YYYY-MMDD')</literal> or
+       <literal>to_date('20000Nov30', 'YYYYMonDD')</literal>.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       In <function>to_timestamp</function> and <function>to_date</function>,
+       the <literal>CC</literal> (century) field is accepted but ignored
+       if there is a <literal>YYY</literal>, <literal>YYYY</literal> or
+       <literal>Y,YYY</literal> field. If <literal>CC</literal> is used with
+       <literal>YY</literal> or <literal>Y</literal> then the result is
+       computed as that year in the specified century.  If the century is
+       specified but the year is not, the first year of the century
+       is assumed.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       In <function>to_timestamp</function> and <function>to_date</function>,
+       weekday names or numbers (<literal>DAY</literal>, <literal>D</literal>,
+       and related field types) are accepted but are ignored for purposes of
+       computing the result.  The same is true for quarter
+       (<literal>Q</literal>) fields.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       In <function>to_timestamp</function> and <function>to_date</function>,
+       an ISO 8601 week-numbering date (as distinct from a Gregorian date)
+       can be specified in one of two ways:
+       <itemizedlist>
+        <listitem>
+         <para>
+          Year, week number, and weekday:  for
+          example <literal>to_date('2006-42-4', 'IYYY-IW-ID')</literal>
+          returns the date <literal>2006-10-19</literal>.
+          If you omit the weekday it is assumed to be 1 (Monday).
+         </para>
+        </listitem>
+        <listitem>
+         <para>
+          Year and day of year:  for example <literal>to_date('2006-291',
+          'IYYY-IDDD')</literal> also returns <literal>2006-10-19</literal>.
+         </para>
+        </listitem>
+       </itemizedlist>
+      </para>
+      <para>
+       Attempting to enter a date using a mixture of ISO 8601 week-numbering
+       fields and Gregorian date fields is nonsensical, and will cause an
+       error.  In the context of an ISO 8601 week-numbering year, the
+       concept of a <quote>month</quote> or <quote>day of month</quote> has no
+       meaning.  In the context of a Gregorian year, the ISO week has no
+       meaning.
+      </para>
+      <caution>
+       <para>
+        While <function>to_date</function> will reject a mixture of
+        Gregorian and ISO week-numbering date
+        fields, <function>to_char</function> will not, since output format
+        specifications like <literal>YYYY-MM-DD (IYYY-IDDD)</literal> can be
+        useful.  But avoid writing something like <literal>IYYY-MM-DD</literal>;
+        that would yield surprising results near the start of the year.
+        (See <xref linkend="functions-datetime-extract"/> for more
+        information.)
+       </para>
+      </caution>
+     </listitem>
+
+     <listitem>
+      <para>
+       In <function>to_timestamp</function>, millisecond
+       (<literal>MS</literal>) or microsecond (<literal>US</literal>)
+       fields are used as the
+       seconds digits after the decimal point. For example
+       <literal>to_timestamp('12.3', 'SS.MS')</literal> is not 3 milliseconds,
+       but 300, because the conversion treats it as 12 + 0.3 seconds.
+       So, for the format <literal>SS.MS</literal>, the input values
+       <literal>12.3</literal>, <literal>12.30</literal>,
+       and <literal>12.300</literal> specify the
+       same number of milliseconds. To get three milliseconds, one must write
+       <literal>12.003</literal>, which the conversion treats as
+       12 + 0.003 = 12.003 seconds.
+      </para>
+
+      <para>
+       Here is a more
+       complex example:
+       <literal>to_timestamp('15:12:02.020.001230', 'HH24:MI:SS.MS.US')</literal>
+       is 15 hours, 12 minutes, and 2 seconds + 20 milliseconds +
+       1230 microseconds = 2.021230 seconds.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+        <function>to_char(..., 'ID')</function>'s day of the week numbering
+        matches the <function>extract(isodow from ...)</function> function, but
+        <function>to_char(..., 'D')</function>'s does not match
+        <function>extract(dow from ...)</function>'s day numbering.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+        <function>to_char(interval)</function> formats <literal>HH</literal> and
+        <literal>HH12</literal> as shown on a 12-hour clock, for example zero hours
+        and 36 hours both output as <literal>12</literal>, while <literal>HH24</literal>
+        outputs the full hour value, which can exceed 23 in
+        an <type>interval</type> value.
+      </para>
+     </listitem>
+
+    </itemizedlist>
+   </para>
+
+  <para>
+   <xref linkend="functions-formatting-numeric-table"/> shows the
+   template patterns available for formatting numeric values.
+  </para>
+
+    <table id="functions-formatting-numeric-table">
+     <title>Template Patterns for Numeric Formatting</title>
+     <tgroup cols="2">
+      <thead>
+       <row>
+        <entry>Pattern</entry>
+        <entry>Description</entry>
+       </row>
+      </thead>
+      <tbody>
+       <row>
+        <entry><literal>9</literal></entry>
+        <entry>digit position (can be dropped if insignificant)</entry>
+       </row>
+       <row>
+        <entry><literal>0</literal></entry>
+        <entry>digit position (will not be dropped, even if insignificant)</entry>
+       </row>
+       <row>
+        <entry><literal>.</literal> (period)</entry>
+        <entry>decimal point</entry>
+       </row>
+       <row>
+        <entry><literal>,</literal> (comma)</entry>
+        <entry>group (thousands) separator</entry>
+       </row>
+       <row>
+        <entry><literal>PR</literal></entry>
+        <entry>negative value in angle brackets</entry>
+       </row>
+       <row>
+        <entry><literal>S</literal></entry>
+        <entry>sign anchored to number (uses locale)</entry>
+       </row>
+       <row>
+        <entry><literal>L</literal></entry>
+        <entry>currency symbol (uses locale)</entry>
+       </row>
+       <row>
+        <entry><literal>D</literal></entry>
+        <entry>decimal point (uses locale)</entry>
+       </row>
+       <row>
+        <entry><literal>G</literal></entry>
+        <entry>group separator (uses locale)</entry>
+       </row>
+       <row>
+        <entry><literal>MI</literal></entry>
+        <entry>minus sign in specified position (if number &lt; 0)</entry>
+       </row>
+       <row>
+        <entry><literal>PL</literal></entry>
+        <entry>plus sign in specified position (if number &gt; 0)</entry>
+       </row>
+       <row>
+        <entry><literal>SG</literal></entry>
+        <entry>plus/minus sign in specified position</entry>
+       </row>
+       <row>
+        <entry><literal>RN</literal> or <literal>rn</literal></entry>
+        <entry>Roman numeral (values between 1 and 3999)</entry>
+       </row>
+       <row>
+        <entry><literal>TH</literal> or <literal>th</literal></entry>
+        <entry>ordinal number suffix</entry>
+       </row>
+       <row>
+        <entry><literal>V</literal></entry>
+        <entry>shift specified number of digits (see notes)</entry>
+       </row>
+       <row>
+        <entry><literal>EEEE</literal></entry>
+        <entry>exponent for scientific notation</entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+   <para>
+    Usage notes for numeric formatting:
+
+    <itemizedlist>
+     <listitem>
+      <para>
+       <literal>0</literal> specifies a digit position that will always be printed,
+       even if it contains a leading/trailing zero.  <literal>9</literal> also
+       specifies a digit position, but if it is a leading zero then it will
+       be replaced by a space, while if it is a trailing zero and fill mode
+       is specified then it will be deleted.  (For <function>to_number()</function>,
+       these two pattern characters are equivalent.)
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       If the format provides fewer fractional digits than the number being
+       formatted, <function>to_char()</function> will round the number to
+       the specified number of fractional digits.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       The pattern characters <literal>S</literal>, <literal>L</literal>, <literal>D</literal>,
+       and <literal>G</literal> represent the sign, currency symbol, decimal point,
+       and thousands separator characters defined by the current locale
+       (see <xref linkend="guc-lc-monetary"/>
+       and <xref linkend="guc-lc-numeric"/>).  The pattern characters period
+       and comma represent those exact characters, with the meanings of
+       decimal point and thousands separator, regardless of locale.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       If no explicit provision is made for a sign
+       in <function>to_char()</function>'s pattern, one column will be reserved for
+       the sign, and it will be anchored to (appear just left of) the
+       number.  If <literal>S</literal> appears just left of some <literal>9</literal>'s,
+       it will likewise be anchored to the number.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       A sign formatted using <literal>SG</literal>, <literal>PL</literal>, or
+       <literal>MI</literal> is not anchored to
+       the number; for example,
+       <literal>to_char(-12, 'MI9999')</literal> produces <literal>'-&nbsp;&nbsp;12'</literal>
+       but <literal>to_char(-12, 'S9999')</literal> produces <literal>'&nbsp;&nbsp;-12'</literal>.
+       (The Oracle implementation does not allow the use of
+       <literal>MI</literal> before <literal>9</literal>, but rather
+       requires that <literal>9</literal> precede
+       <literal>MI</literal>.)
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       <literal>TH</literal> does not convert values less than zero
+       and does not convert fractional numbers.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       <literal>PL</literal>, <literal>SG</literal>, and
+       <literal>TH</literal> are <productname>PostgreSQL</productname>
+       extensions.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       In <function>to_number</function>, if non-data template patterns such
+       as <literal>L</literal> or <literal>TH</literal> are used, the
+       corresponding number of input characters are skipped, whether or not
+       they match the template pattern, unless they are data characters
+       (that is, digits, sign, decimal point, or comma).  For
+       example, <literal>TH</literal> would skip two non-data characters.
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       <literal>V</literal> with <function>to_char</function>
+       multiplies the input values by
+       <literal>10^<replaceable>n</replaceable></literal>, where
+       <replaceable>n</replaceable> is the number of digits following
+       <literal>V</literal>.  <literal>V</literal> with
+       <function>to_number</function> divides in a similar manner.
+       The <literal>V</literal> can be thought of as marking the position
+       of an implicit decimal point in the input or output string.
+       <function>to_char</function> and <function>to_number</function>
+       do not support the use of
+       <literal>V</literal> combined with a decimal point
+       (e.g., <literal>99.9V99</literal> is not allowed).
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       <literal>EEEE</literal> (scientific notation) cannot be used in
+       combination with any of the other formatting patterns or
+       modifiers other than digit and decimal point patterns, and must be at the end of the format string
+       (e.g., <literal>9.99EEEE</literal> is a valid pattern).
+      </para>
+     </listitem>
+
+     <listitem>
+      <para>
+       In <function>to_number()</function>, the <literal>RN</literal>
+       pattern converts Roman numerals (in standard form) to numbers.
+       Input is case-insensitive, so <literal>RN</literal>
+       and <literal>rn</literal> are equivalent.  <literal>RN</literal>
+       cannot be used in combination with any other formatting patterns or
+       modifiers except <literal>FM</literal>, which is applicable only
+       in <function>to_char()</function> and is ignored
+       in <function>to_number()</function>.
+      </para>
+     </listitem>
+    </itemizedlist>
+   </para>
+
+   <para>
+    Certain modifiers can be applied to any template pattern to alter its
+    behavior.  For example, <literal>FM99.99</literal>
+    is the <literal>99.99</literal> pattern with the
+    <literal>FM</literal> modifier.
+    <xref linkend="functions-formatting-numericmod-table"/> shows the
+    modifier patterns for numeric formatting.
+   </para>
+
+    <table id="functions-formatting-numericmod-table">
+     <title>Template Pattern Modifiers for Numeric Formatting</title>
+     <tgroup cols="3">
+      <thead>
+       <row>
+        <entry>Modifier</entry>
+        <entry>Description</entry>
+        <entry>Example</entry>
+       </row>
+      </thead>
+      <tbody>
+       <row>
+        <entry><literal>FM</literal> prefix</entry>
+        <entry>fill mode (suppress trailing zeroes and padding blanks)</entry>
+        <entry><literal>FM99.99</literal></entry>
+       </row>
+       <row>
+        <entry><literal>TH</literal> suffix</entry>
+        <entry>upper case ordinal number suffix</entry>
+        <entry><literal>999TH</literal></entry>
+       </row>
+       <row>
+        <entry><literal>th</literal> suffix</entry>
+        <entry>lower case ordinal number suffix</entry>
+        <entry><literal>999th</literal></entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+  <para>
+   <xref linkend="functions-formatting-examples-table"/> shows some
+   examples of the use of the <function>to_char</function> function.
+  </para>
+
+    <table id="functions-formatting-examples-table">
+     <title><function>to_char</function> Examples</title>
+     <tgroup cols="2">
+      <thead>
+       <row>
+        <entry>Expression</entry>
+        <entry>Result</entry>
+       </row>
+      </thead>
+      <tbody>
+       <row>
+        <entry><literal>to_char(current_timestamp, 'Day,&nbsp;DD&nbsp;&nbsp;HH12:MI:SS')</literal></entry>
+        <entry><literal>'Tuesday&nbsp;&nbsp;,&nbsp;06&nbsp;&nbsp;05:39:18'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(current_timestamp, 'FMDay,&nbsp;FMDD&nbsp;&nbsp;HH12:MI:SS')</literal></entry>
+        <entry><literal>'Tuesday,&nbsp;6&nbsp;&nbsp;05:39:18'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(current_timestamp AT TIME ZONE
+        'UTC', 'YYYY-MM-DD"T"HH24:MI:SS"Z"')</literal></entry>
+        <entry><literal>'2022-12-06T05:39:18Z'</literal>,
+        <acronym>ISO</acronym> 8601 extended format</entry>
+       </row>
+       <row>
+        <entry><literal>to_char(-0.1, '99.99')</literal></entry>
+        <entry><literal>'&nbsp;&nbsp;-.10'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(-0.1, 'FM9.99')</literal></entry>
+        <entry><literal>'-.1'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(-0.1, 'FM90.99')</literal></entry>
+        <entry><literal>'-0.1'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(0.1, '0.9')</literal></entry>
+        <entry><literal>'&nbsp;0.1'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(12, '9990999.9')</literal></entry>
+        <entry><literal>'&nbsp;&nbsp;&nbsp;&nbsp;0012.0'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(12, 'FM9990999.9')</literal></entry>
+        <entry><literal>'0012.'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(485, '999')</literal></entry>
+        <entry><literal>'&nbsp;485'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(-485, '999')</literal></entry>
+        <entry><literal>'-485'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(485, '9&nbsp;9&nbsp;9')</literal></entry>
+        <entry><literal>'&nbsp;4&nbsp;8&nbsp;5'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(1485, '9,999')</literal></entry>
+        <entry><literal>'&nbsp;1,485'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(1485, '9G999')</literal></entry>
+        <entry><literal>'&nbsp;1&nbsp;485'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(148.5, '999.999')</literal></entry>
+        <entry><literal>'&nbsp;148.500'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(148.5, 'FM999.999')</literal></entry>
+        <entry><literal>'148.5'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(148.5, 'FM999.990')</literal></entry>
+        <entry><literal>'148.500'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(148.5, '999D999')</literal></entry>
+        <entry><literal>'&nbsp;148,500'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(3148.5, '9G999D999')</literal></entry>
+        <entry><literal>'&nbsp;3&nbsp;148,500'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(-485, '999S')</literal></entry>
+        <entry><literal>'485-'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(-485, '999MI')</literal></entry>
+        <entry><literal>'485-'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(485, '999MI')</literal></entry>
+        <entry><literal>'485&nbsp;'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(485, 'FM999MI')</literal></entry>
+        <entry><literal>'485'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(485, 'PL999')</literal></entry>
+        <entry><literal>'+485'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(485, 'SG999')</literal></entry>
+        <entry><literal>'+485'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(-485, 'SG999')</literal></entry>
+        <entry><literal>'-485'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(-485, '9SG99')</literal></entry>
+        <entry><literal>'4-85'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(-485, '999PR')</literal></entry>
+        <entry><literal>'&lt;485&gt;'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(485, 'L999')</literal></entry>
+        <entry><literal>'DM&nbsp;485'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(485, 'RN')</literal></entry>
+        <entry><literal>'&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;CDLXXXV'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(485, 'FMRN')</literal></entry>
+        <entry><literal>'CDLXXXV'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(5.2, 'FMRN')</literal></entry>
+        <entry><literal>'V'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(482, '999th')</literal></entry>
+        <entry><literal>'&nbsp;482nd'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(485, '"Good&nbsp;number:"999')</literal></entry>
+        <entry><literal>'Good&nbsp;number:&nbsp;485'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(485.8, '"Pre:"999"&nbsp;Post:"&nbsp;.999')</literal></entry>
+        <entry><literal>'Pre:&nbsp;485&nbsp;Post:&nbsp;.800'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(12, '99V999')</literal></entry>
+        <entry><literal>'&nbsp;12000'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(12.4, '99V999')</literal></entry>
+        <entry><literal>'&nbsp;12400'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(12.45, '99V9')</literal></entry>
+        <entry><literal>'&nbsp;125'</literal></entry>
+       </row>
+       <row>
+        <entry><literal>to_char(0.0004859, '9.99EEEE')</literal></entry>
+        <entry><literal>' 4.86e-04'</literal></entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+  </sect1>
diff --git a/doc/src/sgml/func/func-geometry.sgml b/doc/src/sgml/func/func-geometry.sgml
new file mode 100644
index 0000000000000..ba203af3bd289
--- /dev/null
+++ b/doc/src/sgml/func/func-geometry.sgml
@@ -0,0 +1,1261 @@
+ <sect1 id="functions-geometry">
+  <title>Geometric Functions and Operators</title>
+
+   <para>
+    The geometric types <type>point</type>, <type>box</type>,
+    <type>lseg</type>, <type>line</type>, <type>path</type>,
+    <type>polygon</type>, and <type>circle</type> have a large set of
+    native support functions and operators, shown in <xref
+    linkend="functions-geometry-op-table"/>, <xref
+    linkend="functions-geometry-func-table"/>, and <xref
+    linkend="functions-geometry-conv-table"/>.
+   </para>
+
+   <table id="functions-geometry-op-table">
+    <title>Geometric Operators</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Operator
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>+</literal> <type>point</type>
+        <returnvalue><replaceable>geometric_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Adds the coordinates of the second <type>point</type> to those of each
+        point of the first argument, thus performing translation.
+        Available for <type>point</type>, <type>box</type>, <type>path</type>,
+        <type>circle</type>.
+       </para>
+       <para>
+        <literal>box '(1,1),(0,0)' + point '(2,0)'</literal>
+        <returnvalue>(3,1),(2,0)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>path</type> <literal>+</literal> <type>path</type>
+        <returnvalue>path</returnvalue>
+       </para>
+       <para>
+        Concatenates two open paths (returns NULL if either path is closed).
+       </para>
+       <para>
+        <literal>path '[(0,0),(1,1)]' + path '[(2,2),(3,3),(4,4)]'</literal>
+        <returnvalue>[(0,0),(1,1),(2,2),(3,3),(4,4)]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>-</literal> <type>point</type>
+        <returnvalue><replaceable>geometric_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Subtracts the coordinates of the second <type>point</type> from those
+        of each point of the first argument, thus performing translation.
+        Available for <type>point</type>, <type>box</type>, <type>path</type>,
+        <type>circle</type>.
+       </para>
+       <para>
+        <literal>box '(1,1),(0,0)' - point '(2,0)'</literal>
+        <returnvalue>(-1,1),(-2,0)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>*</literal> <type>point</type>
+        <returnvalue><replaceable>geometric_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Multiplies each point of the first argument by the second
+        <type>point</type> (treating a point as being a complex number
+        represented by real and imaginary parts, and performing standard
+        complex multiplication).  If one interprets
+        the second <type>point</type> as a vector, this is equivalent to
+        scaling the object's size and distance from the origin by the length
+        of the vector, and rotating it counterclockwise around the origin by
+        the vector's angle from the <replaceable>x</replaceable> axis.
+        Available for <type>point</type>, <type>box</type>,<footnote
+        id="functions-geometry-rotation-fn"><para><quote>Rotating</quote> a
+        box with these operators only moves its corner points: the box is
+        still considered to have sides parallel to the axes.  Hence the box's
+        size is not preserved, as a true rotation would do.</para></footnote>
+        <type>path</type>, <type>circle</type>.
+       </para>
+       <para>
+        <literal>path '((0,0),(1,0),(1,1))' * point '(3.0,0)'</literal>
+        <returnvalue>((0,0),(3,0),(3,3))</returnvalue>
+       </para>
+       <para>
+        <literal>path '((0,0),(1,0),(1,1))' * point(cosd(45), sind(45))</literal>
+        <returnvalue>((0,0),&zwsp;(0.7071067811865475,0.7071067811865475),&zwsp;(0,1.414213562373095))</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>/</literal> <type>point</type>
+        <returnvalue><replaceable>geometric_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Divides each point of the first argument by the second
+        <type>point</type> (treating a point as being a complex number
+        represented by real and imaginary parts, and performing standard
+        complex division).  If one interprets
+        the second <type>point</type> as a vector, this is equivalent to
+        scaling the object's size and distance from the origin down by the
+        length of the vector, and rotating it clockwise around the origin by
+        the vector's angle from the <replaceable>x</replaceable> axis.
+        Available for <type>point</type>, <type>box</type>,<footnoteref
+        linkend="functions-geometry-rotation-fn"/> <type>path</type>,
+        <type>circle</type>.
+       </para>
+       <para>
+        <literal>path '((0,0),(1,0),(1,1))' / point '(2.0,0)'</literal>
+        <returnvalue>((0,0),(0.5,0),(0.5,0.5))</returnvalue>
+       </para>
+       <para>
+        <literal>path '((0,0),(1,0),(1,1))' / point(cosd(45), sind(45))</literal>
+        <returnvalue>((0,0),&zwsp;(0.7071067811865476,-0.7071067811865476),&zwsp;(1.4142135623730951,0))</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>@-@</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes the total length.
+        Available for <type>lseg</type>, <type>path</type>.
+       </para>
+       <para>
+        <literal>@-@ path '[(0,0),(1,0),(1,1)]'</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>@@</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>point</returnvalue>
+       </para>
+       <para>
+        Computes the center point.
+        Available for <type>box</type>, <type>lseg</type>,
+        <type>polygon</type>, <type>circle</type>.
+       </para>
+       <para>
+        <literal>@@ box '(2,2),(0,0)'</literal>
+        <returnvalue>(1,1)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>#</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the number of points.
+        Available for <type>path</type>, <type>polygon</type>.
+       </para>
+       <para>
+        <literal># path '((1,0),(0,1),(-1,0))'</literal>
+        <returnvalue>3</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>#</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>point</returnvalue>
+       </para>
+       <para>
+        Computes the point of intersection, or NULL if there is none.
+        Available for <type>lseg</type>, <type>line</type>.
+       </para>
+       <para>
+        <literal>lseg '[(0,0),(1,1)]' # lseg '[(1,0),(0,1)]'</literal>
+        <returnvalue>(0.5,0.5)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>box</type> <literal>#</literal> <type>box</type>
+        <returnvalue>box</returnvalue>
+       </para>
+       <para>
+        Computes the intersection of two boxes, or NULL if there is none.
+       </para>
+       <para>
+        <literal>box '(2,2),(-1,-1)' # box '(1,1),(-2,-2)'</literal>
+        <returnvalue>(1,1),(-1,-1)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>##</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>point</returnvalue>
+       </para>
+       <para>
+        Computes the closest point to the first object on the second object.
+        Available for these pairs of types:
+        (<type>point</type>, <type>box</type>),
+        (<type>point</type>, <type>lseg</type>),
+        (<type>point</type>, <type>line</type>),
+        (<type>lseg</type>, <type>box</type>),
+        (<type>lseg</type>, <type>lseg</type>),
+        (<type>line</type>, <type>lseg</type>).
+       </para>
+       <para>
+        <literal>point '(0,0)' ## lseg '[(2,0),(0,2)]'</literal>
+        <returnvalue>(1,1)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>&lt;-&gt;</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes the distance between the objects.
+        Available for all seven geometric types, for all combinations
+        of <type>point</type> with another geometric type, and for
+        these additional pairs of types:
+        (<type>box</type>, <type>lseg</type>),
+        (<type>lseg</type>, <type>line</type>),
+        (<type>polygon</type>, <type>circle</type>)
+        (and the commutator cases).
+       </para>
+       <para>
+        <literal>circle '&lt;(0,0),1&gt;' &lt;-&gt; circle '&lt;(5,0),1&gt;'</literal>
+        <returnvalue>3</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>@&gt;</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does first object contain second?
+        Available for these pairs of types:
+        (<literal>box</literal>, <literal>point</literal>),
+        (<literal>box</literal>, <literal>box</literal>),
+        (<literal>path</literal>, <literal>point</literal>),
+        (<literal>polygon</literal>, <literal>point</literal>),
+        (<literal>polygon</literal>, <literal>polygon</literal>),
+        (<literal>circle</literal>, <literal>point</literal>),
+        (<literal>circle</literal>, <literal>circle</literal>).
+       </para>
+       <para>
+        <literal>circle '&lt;(0,0),2&gt;' @&gt; point '(1,1)'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>&lt;@</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is first object contained in or on second?
+        Available for these pairs of types:
+        (<literal>point</literal>, <literal>box</literal>),
+        (<literal>point</literal>, <literal>lseg</literal>),
+        (<literal>point</literal>, <literal>line</literal>),
+        (<literal>point</literal>, <literal>path</literal>),
+        (<literal>point</literal>, <literal>polygon</literal>),
+        (<literal>point</literal>, <literal>circle</literal>),
+        (<literal>box</literal>, <literal>box</literal>),
+        (<literal>lseg</literal>, <literal>box</literal>),
+        (<literal>lseg</literal>, <literal>line</literal>),
+        (<literal>polygon</literal>, <literal>polygon</literal>),
+        (<literal>circle</literal>, <literal>circle</literal>).
+       </para>
+       <para>
+        <literal>point '(1,1)' &lt;@ circle '&lt;(0,0),2&gt;'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>&amp;&amp;</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Do these objects overlap?  (One point in common makes this true.)
+        Available for <type>box</type>, <type>polygon</type>,
+        <type>circle</type>.
+       </para>
+       <para>
+        <literal>box '(1,1),(0,0)' &amp;&amp; box '(2,2),(0,0)'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>&lt;&lt;</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is first object strictly left of second?
+        Available for <type>point</type>, <type>box</type>,
+        <type>polygon</type>, <type>circle</type>.
+       </para>
+       <para>
+        <literal>circle '&lt;(0,0),1&gt;' &lt;&lt; circle '&lt;(5,0),1&gt;'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>&gt;&gt;</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is first object strictly right of second?
+        Available for <type>point</type>, <type>box</type>,
+        <type>polygon</type>, <type>circle</type>.
+       </para>
+       <para>
+        <literal>circle '&lt;(5,0),1&gt;' &gt;&gt; circle '&lt;(0,0),1&gt;'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>&amp;&lt;</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does first object not extend to the right of second?
+        Available for <type>box</type>, <type>polygon</type>,
+        <type>circle</type>.
+       </para>
+       <para>
+        <literal>box '(1,1),(0,0)' &amp;&lt; box '(2,2),(0,0)'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>&amp;&gt;</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does first object not extend to the left of second?
+        Available for <type>box</type>, <type>polygon</type>,
+        <type>circle</type>.
+       </para>
+       <para>
+        <literal>box '(3,3),(0,0)' &amp;&gt; box '(2,2),(0,0)'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>&lt;&lt;|</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is first object strictly below second?
+        Available for <type>point</type>, <type>box</type>, <type>polygon</type>,
+        <type>circle</type>.
+       </para>
+       <para>
+        <literal>box '(3,3),(0,0)' &lt;&lt;| box '(5,5),(3,4)'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>|&gt;&gt;</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is first object strictly above second?
+        Available for <type>point</type>, <type>box</type>, <type>polygon</type>,
+        <type>circle</type>.
+       </para>
+       <para>
+        <literal>box '(5,5),(3,4)' |&gt;&gt; box '(3,3),(0,0)'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>&amp;&lt;|</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does first object not extend above second?
+        Available for <type>box</type>, <type>polygon</type>,
+        <type>circle</type>.
+       </para>
+       <para>
+        <literal>box '(1,1),(0,0)' &amp;&lt;| box '(2,2),(0,0)'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>|&amp;&gt;</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does first object not extend below second?
+        Available for <type>box</type>, <type>polygon</type>,
+        <type>circle</type>.
+       </para>
+       <para>
+        <literal>box '(3,3),(0,0)' |&amp;&gt; box '(2,2),(0,0)'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>box</type> <literal>&lt;^</literal> <type>box</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is first object below second (allows edges to touch)?
+       </para>
+       <para>
+        <literal>box '((1,1),(0,0))' &lt;^ box '((2,2),(1,1))'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>box</type> <literal>&gt;^</literal> <type>box</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is first object above second (allows edges to touch)?
+       </para>
+       <para>
+        <literal>box '((2,2),(1,1))' &gt;^ box '((1,1),(0,0))'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>?#</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Do these objects intersect?
+        Available for these pairs of types:
+        (<type>box</type>, <type>box</type>),
+        (<type>lseg</type>, <type>box</type>),
+        (<type>lseg</type>, <type>lseg</type>),
+        (<type>lseg</type>, <type>line</type>),
+        (<type>line</type>, <type>box</type>),
+        (<type>line</type>, <type>line</type>),
+        (<type>path</type>, <type>path</type>).
+       </para>
+       <para>
+        <literal>lseg '[(-1,0),(1,0)]' ?# box '(2,2),(-2,-2)'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>?-</literal> <type>line</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para role="func_signature">
+        <literal>?-</literal> <type>lseg</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is line horizontal?
+       </para>
+       <para>
+        <literal>?- lseg '[(-1,0),(1,0)]'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>point</type> <literal>?-</literal> <type>point</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Are points horizontally aligned (that is, have same y coordinate)?
+       </para>
+       <para>
+        <literal>point '(1,0)' ?- point '(0,0)'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>?|</literal> <type>line</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para role="func_signature">
+        <literal>?|</literal> <type>lseg</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is line vertical?
+       </para>
+       <para>
+        <literal>?| lseg '[(-1,0),(1,0)]'</literal>
+        <returnvalue>f</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>point</type> <literal>?|</literal> <type>point</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Are points vertically aligned (that is, have same x coordinate)?
+       </para>
+       <para>
+        <literal>point '(0,1)' ?| point '(0,0)'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>line</type> <literal>?-|</literal> <type>line</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para role="func_signature">
+        <type>lseg</type> <literal>?-|</literal> <type>lseg</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Are lines perpendicular?
+       </para>
+       <para>
+        <literal>lseg '[(0,0),(0,1)]' ?-| lseg '[(0,0),(1,0)]'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>line</type> <literal>?||</literal> <type>line</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para role="func_signature">
+        <type>lseg</type> <literal>?||</literal> <type>lseg</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Are lines parallel?
+       </para>
+       <para>
+        <literal>lseg '[(-1,0),(1,0)]' ?|| lseg '[(-1,2),(1,2)]'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>geometric_type</replaceable> <literal>~=</literal> <replaceable>geometric_type</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Are these objects the same?
+        Available for <type>point</type>, <type>box</type>,
+        <type>polygon</type>, <type>circle</type>.
+       </para>
+       <para>
+        <literal>polygon '((0,0),(1,1))' ~= polygon '((1,1),(0,0))'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <caution>
+    <para>
+     Note that the <quote>same as</quote> operator, <literal>~=</literal>,
+     represents the usual notion of equality for the <type>point</type>,
+     <type>box</type>, <type>polygon</type>, and <type>circle</type> types.
+     Some of the geometric types also have an <literal>=</literal> operator, but
+     <literal>=</literal> compares for equal <emphasis>areas</emphasis> only.
+     The other scalar comparison operators (<literal>&lt;=</literal> and so
+     on), where available for these types, likewise compare areas.
+    </para>
+   </caution>
+
+   <note>
+    <para>
+     Before <productname>PostgreSQL</productname> 14, the point
+     is strictly below/above comparison operators <type>point</type>
+     <literal>&lt;&lt;|</literal> <type>point</type> and <type>point</type>
+     <literal>|&gt;&gt;</literal> <type>point</type> were respectively
+     called <literal>&lt;^</literal> and <literal>&gt;^</literal>.  These
+     names are still available, but are deprecated and will eventually be
+     removed.
+    </para>
+   </note>
+
+   <table id="functions-geometry-func-table">
+    <title>Geometric Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>area</primary>
+        </indexterm>
+        <function>area</function> ( <replaceable>geometric_type</replaceable> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes area.
+        Available for <type>box</type>, <type>path</type>, <type>circle</type>.
+        A <type>path</type> input must be closed, else NULL is returned.
+        Also, if the <type>path</type> is self-intersecting, the result may be
+        meaningless.
+       </para>
+       <para>
+        <literal>area(box '(2,2),(0,0)')</literal>
+        <returnvalue>4</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>center</primary>
+        </indexterm>
+        <function>center</function> ( <replaceable>geometric_type</replaceable> )
+        <returnvalue>point</returnvalue>
+       </para>
+       <para>
+        Computes center point.
+        Available for <type>box</type>, <type>circle</type>.
+       </para>
+       <para>
+        <literal>center(box '(1,2),(0,0)')</literal>
+        <returnvalue>(0.5,1)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>diagonal</primary>
+        </indexterm>
+        <function>diagonal</function> ( <type>box</type> )
+        <returnvalue>lseg</returnvalue>
+       </para>
+       <para>
+        Extracts box's diagonal as a line segment
+        (same as <function>lseg(box)</function>).
+       </para>
+       <para>
+        <literal>diagonal(box '(1,2),(0,0)')</literal>
+        <returnvalue>[(1,2),(0,0)]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>diameter</primary>
+        </indexterm>
+        <function>diameter</function> ( <type>circle</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes diameter of circle.
+       </para>
+       <para>
+        <literal>diameter(circle '&lt;(0,0),2&gt;')</literal>
+        <returnvalue>4</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>height</primary>
+        </indexterm>
+        <function>height</function> ( <type>box</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes vertical size of box.
+       </para>
+       <para>
+        <literal>height(box '(1,2),(0,0)')</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>isclosed</primary>
+        </indexterm>
+        <function>isclosed</function> ( <type>path</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is path closed?
+       </para>
+       <para>
+        <literal>isclosed(path '((0,0),(1,1),(2,0))')</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>isopen</primary>
+        </indexterm>
+        <function>isopen</function> ( <type>path</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is path open?
+       </para>
+       <para>
+        <literal>isopen(path '[(0,0),(1,1),(2,0)]')</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>length</primary>
+        </indexterm>
+        <function>length</function> ( <replaceable>geometric_type</replaceable> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes the total length.
+        Available for <type>lseg</type>, <type>path</type>.
+       </para>
+       <para>
+        <literal>length(path '((-1,0),(1,0))')</literal>
+        <returnvalue>4</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>npoints</primary>
+        </indexterm>
+        <function>npoints</function> ( <replaceable>geometric_type</replaceable> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the number of points.
+        Available for <type>path</type>, <type>polygon</type>.
+       </para>
+       <para>
+        <literal>npoints(path '[(0,0),(1,1),(2,0)]')</literal>
+        <returnvalue>3</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pclose</primary>
+        </indexterm>
+        <function>pclose</function> ( <type>path</type> )
+        <returnvalue>path</returnvalue>
+       </para>
+       <para>
+        Converts path to closed form.
+       </para>
+       <para>
+        <literal>pclose(path '[(0,0),(1,1),(2,0)]')</literal>
+        <returnvalue>((0,0),(1,1),(2,0))</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>popen</primary>
+        </indexterm>
+        <function>popen</function> ( <type>path</type> )
+        <returnvalue>path</returnvalue>
+       </para>
+       <para>
+        Converts path to open form.
+       </para>
+       <para>
+        <literal>popen(path '((0,0),(1,1),(2,0))')</literal>
+        <returnvalue>[(0,0),(1,1),(2,0)]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>radius</primary>
+        </indexterm>
+        <function>radius</function> ( <type>circle</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes radius of circle.
+       </para>
+       <para>
+        <literal>radius(circle '&lt;(0,0),2&gt;')</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>slope</primary>
+        </indexterm>
+        <function>slope</function> ( <type>point</type>, <type>point</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes slope of a line drawn through the two points.
+       </para>
+       <para>
+        <literal>slope(point '(0,0)', point '(2,1)')</literal>
+        <returnvalue>0.5</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>width</primary>
+        </indexterm>
+        <function>width</function> ( <type>box</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Computes horizontal size of box.
+       </para>
+       <para>
+        <literal>width(box '(1,2),(0,0)')</literal>
+        <returnvalue>1</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <table id="functions-geometry-conv-table">
+    <title>Geometric Type Conversion Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+     <tbody>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>box</primary>
+        </indexterm>
+        <function>box</function> ( <type>circle</type> )
+        <returnvalue>box</returnvalue>
+       </para>
+       <para>
+        Computes box inscribed within the circle.
+       </para>
+       <para>
+        <literal>box(circle '&lt;(0,0),2&gt;')</literal>
+        <returnvalue>(1.414213562373095,1.414213562373095),&zwsp;(-1.414213562373095,-1.414213562373095)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>box</function> ( <type>point</type> )
+        <returnvalue>box</returnvalue>
+       </para>
+       <para>
+        Converts point to empty box.
+       </para>
+       <para>
+        <literal>box(point '(1,0)')</literal>
+        <returnvalue>(1,0),(1,0)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>box</function> ( <type>point</type>, <type>point</type> )
+        <returnvalue>box</returnvalue>
+       </para>
+       <para>
+        Converts any two corner points to box.
+       </para>
+       <para>
+        <literal>box(point '(0,1)', point '(1,0)')</literal>
+        <returnvalue>(1,1),(0,0)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>box</function> ( <type>polygon</type> )
+        <returnvalue>box</returnvalue>
+       </para>
+       <para>
+        Computes bounding box of polygon.
+       </para>
+       <para>
+        <literal>box(polygon '((0,0),(1,1),(2,0))')</literal>
+        <returnvalue>(2,1),(0,0)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>bound_box</primary>
+        </indexterm>
+        <function>bound_box</function> ( <type>box</type>, <type>box</type> )
+        <returnvalue>box</returnvalue>
+       </para>
+       <para>
+        Computes bounding box of two boxes.
+       </para>
+       <para>
+        <literal>bound_box(box '(1,1),(0,0)', box '(4,4),(3,3)')</literal>
+        <returnvalue>(4,4),(0,0)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>circle</primary>
+        </indexterm>
+        <function>circle</function> ( <type>box</type> )
+        <returnvalue>circle</returnvalue>
+       </para>
+       <para>
+        Computes smallest circle enclosing box.
+       </para>
+       <para>
+        <literal>circle(box '(1,1),(0,0)')</literal>
+        <returnvalue>&lt;(0.5,0.5),0.7071067811865476&gt;</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>circle</function> ( <type>point</type>, <type>double precision</type> )
+        <returnvalue>circle</returnvalue>
+       </para>
+       <para>
+        Constructs circle from center and radius.
+       </para>
+       <para>
+        <literal>circle(point '(0,0)', 2.0)</literal>
+        <returnvalue>&lt;(0,0),2&gt;</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>circle</function> ( <type>polygon</type> )
+        <returnvalue>circle</returnvalue>
+       </para>
+       <para>
+        Converts polygon to circle.  The circle's center is the mean of the
+        positions of the polygon's points, and the radius is the average
+        distance of the polygon's points from that center.
+       </para>
+       <para>
+        <literal>circle(polygon '((0,0),(1,3),(2,0))')</literal>
+        <returnvalue>&lt;(1,1),1.6094757082487299&gt;</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>line</primary>
+        </indexterm>
+        <function>line</function> ( <type>point</type>, <type>point</type> )
+        <returnvalue>line</returnvalue>
+       </para>
+       <para>
+        Converts two points to the line through them.
+       </para>
+       <para>
+        <literal>line(point '(-1,0)', point '(1,0)')</literal>
+        <returnvalue>{0,-1,0}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>lseg</primary>
+        </indexterm>
+        <function>lseg</function> ( <type>box</type> )
+        <returnvalue>lseg</returnvalue>
+       </para>
+       <para>
+        Extracts box's diagonal as a line segment.
+       </para>
+       <para>
+        <literal>lseg(box '(1,0),(-1,0)')</literal>
+        <returnvalue>[(1,0),(-1,0)]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>lseg</function> ( <type>point</type>, <type>point</type> )
+        <returnvalue>lseg</returnvalue>
+       </para>
+       <para>
+        Constructs line segment from two endpoints.
+       </para>
+       <para>
+        <literal>lseg(point '(-1,0)', point '(1,0)')</literal>
+        <returnvalue>[(-1,0),(1,0)]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>path</primary>
+        </indexterm>
+        <function>path</function> ( <type>polygon</type> )
+        <returnvalue>path</returnvalue>
+       </para>
+       <para>
+        Converts polygon to a closed path with the same list of points.
+       </para>
+       <para>
+        <literal>path(polygon '((0,0),(1,1),(2,0))')</literal>
+        <returnvalue>((0,0),(1,1),(2,0))</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>point</primary>
+        </indexterm>
+        <function>point</function> ( <type>double precision</type>, <type>double precision</type> )
+        <returnvalue>point</returnvalue>
+       </para>
+       <para>
+        Constructs point from its coordinates.
+       </para>
+       <para>
+        <literal>point(23.4, -44.5)</literal>
+        <returnvalue>(23.4,-44.5)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>point</function> ( <type>box</type> )
+        <returnvalue>point</returnvalue>
+       </para>
+       <para>
+        Computes center of box.
+       </para>
+       <para>
+        <literal>point(box '(1,0),(-1,0)')</literal>
+        <returnvalue>(0,0)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>point</function> ( <type>circle</type> )
+        <returnvalue>point</returnvalue>
+       </para>
+       <para>
+        Computes center of circle.
+       </para>
+       <para>
+        <literal>point(circle '&lt;(0,0),2&gt;')</literal>
+        <returnvalue>(0,0)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>point</function> ( <type>lseg</type> )
+        <returnvalue>point</returnvalue>
+       </para>
+       <para>
+        Computes center of line segment.
+       </para>
+       <para>
+        <literal>point(lseg '[(-1,0),(1,0)]')</literal>
+        <returnvalue>(0,0)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>point</function> ( <type>polygon</type> )
+        <returnvalue>point</returnvalue>
+       </para>
+       <para>
+        Computes center of polygon (the mean of the
+        positions of the polygon's points).
+       </para>
+       <para>
+        <literal>point(polygon '((0,0),(1,1),(2,0))')</literal>
+        <returnvalue>(1,0.3333333333333333)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>polygon</primary>
+        </indexterm>
+        <function>polygon</function> ( <type>box</type> )
+        <returnvalue>polygon</returnvalue>
+       </para>
+       <para>
+        Converts box to a 4-point polygon.
+       </para>
+       <para>
+        <literal>polygon(box '(1,1),(0,0)')</literal>
+        <returnvalue>((0,0),(0,1),(1,1),(1,0))</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>polygon</function> ( <type>circle</type> )
+        <returnvalue>polygon</returnvalue>
+       </para>
+       <para>
+        Converts circle to a 12-point polygon.
+       </para>
+       <para>
+        <literal>polygon(circle '&lt;(0,0),2&gt;')</literal>
+        <returnvalue>((-2,0),&zwsp;(-1.7320508075688774,0.9999999999999999),&zwsp;(-1.0000000000000002,1.7320508075688772),&zwsp;(-1.2246063538223773e-16,2),&zwsp;(0.9999999999999996,1.7320508075688774),&zwsp;(1.732050807568877,1.0000000000000007),&zwsp;(2,2.4492127076447545e-16),&zwsp;(1.7320508075688776,-0.9999999999999994),&zwsp;(1.0000000000000009,-1.7320508075688767),&zwsp;(3.673819061467132e-16,-2),&zwsp;(-0.9999999999999987,-1.732050807568878),&zwsp;(-1.7320508075688767,-1.0000000000000009))</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>polygon</function> ( <type>integer</type>, <type>circle</type> )
+        <returnvalue>polygon</returnvalue>
+       </para>
+       <para>
+        Converts circle to an <replaceable>n</replaceable>-point polygon.
+       </para>
+       <para>
+        <literal>polygon(4, circle '&lt;(3,0),1&gt;')</literal>
+        <returnvalue>((2,0),&zwsp;(3,1),&zwsp;(4,1.2246063538223773e-16),&zwsp;(3,-1))</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>polygon</function> ( <type>path</type> )
+        <returnvalue>polygon</returnvalue>
+       </para>
+       <para>
+        Converts closed path to a polygon with the same list of points.
+       </para>
+       <para>
+        <literal>polygon(path '((0,0),(1,1),(2,0))')</literal>
+        <returnvalue>((0,0),(1,1),(2,0))</returnvalue>
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
+    <para>
+     It is possible to access the two component numbers of a <type>point</type>
+     as though the point were an array with indexes 0 and 1.  For example, if
+     <literal>t.p</literal> is a <type>point</type> column then
+     <literal>SELECT p[0] FROM t</literal> retrieves the X coordinate and
+     <literal>UPDATE t SET p[1] = ...</literal> changes the Y coordinate.
+     In the same way, a value of type <type>box</type> or <type>lseg</type> can be treated
+     as an array of two <type>point</type> values.
+    </para>
+
+  </sect1>
diff --git a/doc/src/sgml/func/func-info.sgml b/doc/src/sgml/func/func-info.sgml
new file mode 100644
index 0000000000000..b507bfaf64b19
--- /dev/null
+++ b/doc/src/sgml/func/func-info.sgml
@@ -0,0 +1,3790 @@
+ <sect1 id="functions-info">
+  <title>System Information Functions and Operators</title>
+
+   <para>
+    The functions described in this section are used to obtain various
+    information about a <productname>PostgreSQL</productname> installation.
+   </para>
+
+  <sect2 id="functions-info-session">
+   <title>Session Information Functions</title>
+
+  <para>
+   <xref linkend="functions-info-session-table"/> shows several
+   functions that extract session and system information.
+  </para>
+
+  <para>
+   In addition to the functions listed in this section, there are a number of
+   functions related to the statistics system that also provide system
+   information. See <xref linkend="monitoring-stats-functions"/> for more
+   information.
+  </para>
+
+   <table id="functions-info-session-table">
+    <title>Session Information Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>current_catalog</primary>
+        </indexterm>
+        <function>current_catalog</function>
+        <returnvalue>name</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>current_database</primary>
+        </indexterm>
+        <function>current_database</function> ()
+        <returnvalue>name</returnvalue>
+       </para>
+       <para>
+        Returns the name of the current database.  (Databases are
+        called <quote>catalogs</quote> in the SQL standard,
+        so <function>current_catalog</function> is the standard's
+        spelling.)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>current_query</primary>
+        </indexterm>
+        <function>current_query</function> ()
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the text of the currently executing query, as submitted
+        by the client (which might contain more than one statement).
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>current_role</primary>
+        </indexterm>
+        <function>current_role</function>
+        <returnvalue>name</returnvalue>
+       </para>
+       <para>
+        This is equivalent to <function>current_user</function>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>current_schema</primary>
+        </indexterm>
+        <indexterm>
+         <primary>schema</primary>
+         <secondary>current</secondary>
+        </indexterm>
+        <function>current_schema</function>
+        <returnvalue>name</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>current_schema</function> ()
+        <returnvalue>name</returnvalue>
+       </para>
+       <para>
+        Returns the name of the schema that is first in the search path (or a
+        null value if the search path is empty).  This is the schema that will
+        be used for any tables or other named objects that are created without
+        specifying a target schema.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>current_schemas</primary>
+        </indexterm>
+        <indexterm>
+         <primary>search path</primary>
+         <secondary>current</secondary>
+        </indexterm>
+        <function>current_schemas</function> ( <parameter>include_implicit</parameter> <type>boolean</type> )
+        <returnvalue>name[]</returnvalue>
+       </para>
+       <para>
+        Returns an array of the names of all schemas presently in the
+        effective search path, in their priority order.  (Items in the current
+        <xref linkend="guc-search-path"/> setting that do not correspond to
+        existing, searchable schemas are omitted.)  If the Boolean argument
+        is <literal>true</literal>, then implicitly-searched system schemas
+        such as <literal>pg_catalog</literal> are included in the result.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>current_user</primary>
+        </indexterm>
+        <indexterm>
+         <primary>user</primary>
+         <secondary>current</secondary>
+        </indexterm>
+        <function>current_user</function>
+        <returnvalue>name</returnvalue>
+       </para>
+       <para>
+        Returns the user name of the current execution context.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>inet_client_addr</primary>
+        </indexterm>
+        <function>inet_client_addr</function> ()
+        <returnvalue>inet</returnvalue>
+       </para>
+       <para>
+        Returns the IP address of the current client,
+        or <literal>NULL</literal> if the current connection is via a
+        Unix-domain socket.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>inet_client_port</primary>
+        </indexterm>
+        <function>inet_client_port</function> ()
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the IP port number of the current client,
+        or <literal>NULL</literal> if the current connection is via a
+        Unix-domain socket.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>inet_server_addr</primary>
+        </indexterm>
+        <function>inet_server_addr</function> ()
+        <returnvalue>inet</returnvalue>
+       </para>
+       <para>
+        Returns the IP address on which the server accepted the current
+        connection,
+        or <literal>NULL</literal> if the current connection is via a
+        Unix-domain socket.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>inet_server_port</primary>
+        </indexterm>
+        <function>inet_server_port</function> ()
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the IP port number on which the server accepted the current
+        connection,
+        or <literal>NULL</literal> if the current connection is via a
+        Unix-domain socket.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_backend_pid</primary>
+        </indexterm>
+        <function>pg_backend_pid</function> ()
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the process ID of the server process attached to the current
+        session.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_blocking_pids</primary>
+        </indexterm>
+        <function>pg_blocking_pids</function> ( <type>integer</type> )
+        <returnvalue>integer[]</returnvalue>
+       </para>
+       <para>
+        Returns an array of the process ID(s) of the sessions that are
+        blocking the server process with the specified process ID from
+        acquiring a lock, or an empty array if there is no such server process
+        or it is not blocked.
+       </para>
+       <para>
+        One server process blocks another if it either holds a lock that
+        conflicts with the blocked process's lock request (hard block), or is
+        waiting for a lock that would conflict with the blocked process's lock
+        request and is ahead of it in the wait queue (soft block).  When using
+        parallel queries the result always lists client-visible process IDs
+        (that is, <function>pg_backend_pid</function> results) even if the
+        actual lock is held or awaited by a child worker process.  As a result
+        of that, there may be duplicated PIDs in the result.  Also note that
+        when a prepared transaction holds a conflicting lock, it will be
+        represented by a zero process ID.
+       </para>
+       <para>
+        Frequent calls to this function could have some impact on database
+        performance, because it needs exclusive access to the lock manager's
+        shared state for a short time.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_conf_load_time</primary>
+        </indexterm>
+        <function>pg_conf_load_time</function> ()
+        <returnvalue>timestamp with time zone</returnvalue>
+       </para>
+       <para>
+        Returns the time when the server configuration files were last loaded.
+        If the current session was alive at the time, this will be the time
+        when the session itself re-read the configuration files (so the
+        reading will vary a little in different sessions).  Otherwise it is
+        the time when the postmaster process re-read the configuration files.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_current_logfile</primary>
+        </indexterm>
+        <indexterm>
+         <primary>Logging</primary>
+         <secondary>pg_current_logfile function</secondary>
+        </indexterm>
+        <indexterm>
+          <primary>current_logfiles</primary>
+          <secondary>and the pg_current_logfile function</secondary>
+        </indexterm>
+        <indexterm>
+         <primary>Logging</primary>
+         <secondary>current_logfiles file and the pg_current_logfile
+         function</secondary>
+        </indexterm>
+        <function>pg_current_logfile</function> ( <optional> <type>text</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the path name of the log file currently in use by the logging
+        collector.  The path includes the <xref linkend="guc-log-directory"/>
+        directory and the individual log file name.  The result
+        is <literal>NULL</literal> if the logging collector is disabled.
+        When multiple log files exist, each in a different
+        format, <function>pg_current_logfile</function> without an argument
+        returns the path of the file having the first format found in the
+        ordered list: <literal>stderr</literal>,
+        <literal>csvlog</literal>, <literal>jsonlog</literal>.
+        <literal>NULL</literal> is returned if no log file has any of these
+        formats.
+        To request information about a specific log file format, supply
+        either <literal>csvlog</literal>, <literal>jsonlog</literal> or
+        <literal>stderr</literal> as the
+        value of the optional parameter. The result is <literal>NULL</literal>
+        if the log format requested is not configured in
+        <xref linkend="guc-log-destination"/>.
+        The result reflects the contents of
+        the <filename>current_logfiles</filename> file.
+       </para>
+       <para>
+        This function is restricted to superusers and roles with privileges of
+        the <literal>pg_monitor</literal> role by default, but other users can
+        be granted EXECUTE to run the function.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_loaded_modules</primary>
+        </indexterm>
+        <function>pg_get_loaded_modules</function> ()
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>module_name</parameter> <type>text</type>,
+        <parameter>version</parameter> <type>text</type>,
+        <parameter>file_name</parameter> <type>text</type> )
+       </para>
+       <para>
+        Returns a list of the loadable modules that are loaded into the
+        current server session.  The <parameter>module_name</parameter>
+        and <parameter>version</parameter> fields are NULL unless the
+        module author supplied values for them using
+        the <literal>PG_MODULE_MAGIC_EXT</literal> macro.
+        The <parameter>file_name</parameter> field gives the file
+        name of the module (shared library).
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_my_temp_schema</primary>
+        </indexterm>
+        <function>pg_my_temp_schema</function> ()
+        <returnvalue>oid</returnvalue>
+       </para>
+       <para>
+        Returns the OID of the current session's temporary schema, or zero if
+        it has none (because it has not created any temporary tables).
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_is_other_temp_schema</primary>
+        </indexterm>
+        <function>pg_is_other_temp_schema</function> ( <type>oid</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Returns true if the given OID is the OID of another session's
+        temporary schema.  (This can be useful, for example, to exclude other
+        sessions' temporary tables from a catalog display.)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_jit_available</primary>
+        </indexterm>
+        <function>pg_jit_available</function> ()
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Returns true if a <acronym>JIT</acronym> compiler extension is
+        available (see <xref linkend="jit"/>) and the
+        <xref linkend="guc-jit"/> configuration parameter is set to
+        <literal>on</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_numa_available</primary>
+        </indexterm>
+        <function>pg_numa_available</function> ()
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Returns true if the server has been compiled with <acronym>NUMA</acronym> support.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_listening_channels</primary>
+        </indexterm>
+        <function>pg_listening_channels</function> ()
+        <returnvalue>setof text</returnvalue>
+       </para>
+       <para>
+        Returns the set of names of asynchronous notification channels that
+        the current session is listening to.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_notification_queue_usage</primary>
+        </indexterm>
+        <function>pg_notification_queue_usage</function> ()
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Returns the fraction (0&ndash;1) of the asynchronous notification
+        queue's maximum size that is currently occupied by notifications that
+        are waiting to be processed.
+        See <xref linkend="sql-listen"/> and <xref linkend="sql-notify"/>
+        for more information.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_postmaster_start_time</primary>
+        </indexterm>
+        <function>pg_postmaster_start_time</function> ()
+        <returnvalue>timestamp with time zone</returnvalue>
+       </para>
+       <para>
+        Returns the time when the server started.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_safe_snapshot_blocking_pids</primary>
+        </indexterm>
+        <function>pg_safe_snapshot_blocking_pids</function> ( <type>integer</type> )
+        <returnvalue>integer[]</returnvalue>
+       </para>
+       <para>
+        Returns an array of the process ID(s) of the sessions that are blocking
+        the server process with the specified process ID from acquiring a safe
+        snapshot, or an empty array if there is no such server process or it
+        is not blocked.
+       </para>
+       <para>
+        A session running a <literal>SERIALIZABLE</literal> transaction blocks
+        a <literal>SERIALIZABLE READ ONLY DEFERRABLE</literal> transaction
+        from acquiring a snapshot until the latter determines that it is safe
+        to avoid taking any predicate locks.  See
+        <xref linkend="xact-serializable"/> for more information about
+        serializable and deferrable transactions.
+       </para>
+       <para>
+        Frequent calls to this function could have some impact on database
+        performance, because it needs access to the predicate lock manager's
+        shared state for a short time.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_trigger_depth</primary>
+        </indexterm>
+        <function>pg_trigger_depth</function> ()
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the current nesting level
+        of <productname>PostgreSQL</productname> triggers (0 if not called,
+        directly or indirectly, from inside a trigger).
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>session_user</primary>
+        </indexterm>
+        <function>session_user</function>
+        <returnvalue>name</returnvalue>
+       </para>
+       <para>
+        Returns the session user's name.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>system_user</primary>
+        </indexterm>
+        <function>system_user</function>
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the authentication method and the identity (if any) that the
+        user presented during the authentication cycle before they were
+        assigned a database role. It is represented as
+        <literal>auth_method:identity</literal> or
+        <literal>NULL</literal> if the user has not been authenticated (for
+        example if <link linkend="auth-trust">Trust authentication</link> has
+        been used).
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>user</primary>
+        </indexterm>
+        <function>user</function>
+        <returnvalue>name</returnvalue>
+       </para>
+       <para>
+        This is equivalent to <function>current_user</function>.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <note>
+    <para>
+     <function>current_catalog</function>,
+     <function>current_role</function>,
+     <function>current_schema</function>,
+     <function>current_user</function>,
+     <function>session_user</function>,
+     and <function>user</function> have special syntactic status
+     in <acronym>SQL</acronym>: they must be called without trailing
+     parentheses.  In PostgreSQL, parentheses can optionally be used with
+     <function>current_schema</function>, but not with the others.
+    </para>
+   </note>
+
+   <para>
+    The <function>session_user</function> is normally the user who initiated
+    the current database connection; but superusers can change this setting
+    with <xref linkend="sql-set-session-authorization"/>.
+    The <function>current_user</function> is the user identifier
+    that is applicable for permission checking. Normally it is equal
+    to the session user, but it can be changed with
+    <xref linkend="sql-set-role"/>.
+    It also changes during the execution of
+    functions with the attribute <literal>SECURITY DEFINER</literal>.
+    In Unix parlance, the session user is the <quote>real user</quote> and
+    the current user is the <quote>effective user</quote>.
+    <function>current_role</function> and <function>user</function> are
+    synonyms for <function>current_user</function>.  (The SQL standard draws
+    a distinction between <function>current_role</function>
+    and <function>current_user</function>, but <productname>PostgreSQL</productname>
+    does not, since it unifies users and roles into a single kind of entity.)
+   </para>
+
+  </sect2>
+
+  <sect2 id="functions-info-access">
+   <title>Access Privilege Inquiry Functions</title>
+
+  <indexterm>
+   <primary>privilege</primary>
+   <secondary>querying</secondary>
+  </indexterm>
+
+  <para>
+   <xref linkend="functions-info-access-table"/> lists functions that
+   allow querying object access privileges programmatically.
+   (See <xref linkend="ddl-priv"/> for more information about
+   privileges.)
+   In these functions, the user whose privileges are being inquired about
+   can be specified by name or by OID
+   (<structname>pg_authid</structname>.<structfield>oid</structfield>), or if
+   the name is given as <literal>public</literal> then the privileges of the
+   PUBLIC pseudo-role are checked.  Also, the <parameter>user</parameter>
+   argument can be omitted entirely, in which case
+   the <function>current_user</function> is assumed.
+   The object that is being inquired about can be specified either by name or
+   by OID, too.  When specifying by name, a schema name can be included if
+   relevant.
+   The access privilege of interest is specified by a text string, which must
+   evaluate to one of the appropriate privilege keywords for the object's type
+   (e.g., <literal>SELECT</literal>).  Optionally, <literal>WITH GRANT
+   OPTION</literal> can be added to a privilege type to test whether the
+   privilege is held with grant option. Also, multiple privilege types can be
+   listed separated by commas, in which case the result will be true if any of
+   the listed privileges is held. (Case of the privilege string is not
+   significant, and extra whitespace is allowed between but not within
+   privilege names.)
+   Some examples:
+<programlisting>
+SELECT has_table_privilege('myschema.mytable', 'select');
+SELECT has_table_privilege('joe', 'mytable', 'INSERT, SELECT WITH GRANT OPTION');
+</programlisting>
+  </para>
+
+   <table id="functions-info-access-table">
+    <title>Access Privilege Inquiry Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>has_any_column_privilege</primary>
+        </indexterm>
+        <function>has_any_column_privilege</function> (
+          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
+          <parameter>table</parameter> <type>text</type> or <type>oid</type>,
+          <parameter>privilege</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does user have privilege for any column of table?
+        This succeeds either if the privilege is held for the whole table, or
+        if there is a column-level grant of the privilege for at least one
+        column.
+        Allowable privilege types are
+        <literal>SELECT</literal>, <literal>INSERT</literal>,
+        <literal>UPDATE</literal>, and <literal>REFERENCES</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>has_column_privilege</primary>
+        </indexterm>
+        <function>has_column_privilege</function> (
+          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
+          <parameter>table</parameter> <type>text</type> or <type>oid</type>,
+          <parameter>column</parameter> <type>text</type> or <type>smallint</type>,
+          <parameter>privilege</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does user have privilege for the specified table column?
+        This succeeds either if the privilege is held for the whole table, or
+        if there is a column-level grant of the privilege for the column.
+        The column can be specified by name or by attribute number
+        (<structname>pg_attribute</structname>.<structfield>attnum</structfield>).
+        Allowable privilege types are
+        <literal>SELECT</literal>, <literal>INSERT</literal>,
+        <literal>UPDATE</literal>, and <literal>REFERENCES</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>has_database_privilege</primary>
+        </indexterm>
+        <function>has_database_privilege</function> (
+          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
+          <parameter>database</parameter> <type>text</type> or <type>oid</type>,
+          <parameter>privilege</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does user have privilege for database?
+        Allowable privilege types are
+        <literal>CREATE</literal>,
+        <literal>CONNECT</literal>,
+        <literal>TEMPORARY</literal>, and
+        <literal>TEMP</literal> (which is equivalent to
+        <literal>TEMPORARY</literal>).
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>has_foreign_data_wrapper_privilege</primary>
+        </indexterm>
+        <function>has_foreign_data_wrapper_privilege</function> (
+          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
+          <parameter>fdw</parameter> <type>text</type> or <type>oid</type>,
+          <parameter>privilege</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does user have privilege for foreign-data wrapper?
+        The only allowable privilege type is <literal>USAGE</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>has_function_privilege</primary>
+        </indexterm>
+        <function>has_function_privilege</function> (
+          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
+          <parameter>function</parameter> <type>text</type> or <type>oid</type>,
+          <parameter>privilege</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does user have privilege for function?
+        The only allowable privilege type is <literal>EXECUTE</literal>.
+       </para>
+       <para>
+        When specifying a function by name rather than by OID, the allowed
+        input is the same as for the <type>regprocedure</type> data type (see
+        <xref linkend="datatype-oid"/>).
+        An example is:
+<programlisting>
+SELECT has_function_privilege('joeuser', 'myfunc(int, text)', 'execute');
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>has_language_privilege</primary>
+        </indexterm>
+        <function>has_language_privilege</function> (
+          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
+          <parameter>language</parameter> <type>text</type> or <type>oid</type>,
+          <parameter>privilege</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does user have privilege for language?
+        The only allowable privilege type is <literal>USAGE</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>has_largeobject_privilege</primary>
+        </indexterm>
+        <function>has_largeobject_privilege</function> (
+          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
+          <parameter>largeobject</parameter> <type>oid</type>,
+          <parameter>privilege</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does user have privilege for large object?
+        Allowable privilege types are
+        <literal>SELECT</literal> and <literal>UPDATE</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>has_parameter_privilege</primary>
+        </indexterm>
+        <function>has_parameter_privilege</function> (
+          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
+          <parameter>parameter</parameter> <type>text</type>,
+          <parameter>privilege</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does user have privilege for configuration parameter?
+        The parameter name is case-insensitive.
+        Allowable privilege types are <literal>SET</literal>
+        and <literal>ALTER SYSTEM</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>has_schema_privilege</primary>
+        </indexterm>
+        <function>has_schema_privilege</function> (
+          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
+          <parameter>schema</parameter> <type>text</type> or <type>oid</type>,
+          <parameter>privilege</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does user have privilege for schema?
+        Allowable privilege types are
+        <literal>CREATE</literal> and
+        <literal>USAGE</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>has_sequence_privilege</primary>
+        </indexterm>
+        <function>has_sequence_privilege</function> (
+          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
+          <parameter>sequence</parameter> <type>text</type> or <type>oid</type>,
+          <parameter>privilege</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does user have privilege for sequence?
+        Allowable privilege types are
+        <literal>USAGE</literal>,
+        <literal>SELECT</literal>, and
+        <literal>UPDATE</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>has_server_privilege</primary>
+        </indexterm>
+        <function>has_server_privilege</function> (
+          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
+          <parameter>server</parameter> <type>text</type> or <type>oid</type>,
+          <parameter>privilege</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does user have privilege for foreign server?
+        The only allowable privilege type is <literal>USAGE</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>has_table_privilege</primary>
+        </indexterm>
+        <function>has_table_privilege</function> (
+          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
+          <parameter>table</parameter> <type>text</type> or <type>oid</type>,
+          <parameter>privilege</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does user have privilege for table?
+        Allowable privilege types
+        are <literal>SELECT</literal>, <literal>INSERT</literal>,
+        <literal>UPDATE</literal>, <literal>DELETE</literal>,
+        <literal>TRUNCATE</literal>, <literal>REFERENCES</literal>,
+        <literal>TRIGGER</literal>, and <literal>MAINTAIN</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>has_tablespace_privilege</primary>
+        </indexterm>
+        <function>has_tablespace_privilege</function> (
+          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
+          <parameter>tablespace</parameter> <type>text</type> or <type>oid</type>,
+          <parameter>privilege</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does user have privilege for tablespace?
+        The only allowable privilege type is <literal>CREATE</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>has_type_privilege</primary>
+        </indexterm>
+        <function>has_type_privilege</function> (
+          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
+          <parameter>type</parameter> <type>text</type> or <type>oid</type>,
+          <parameter>privilege</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does user have privilege for data type?
+        The only allowable privilege type is <literal>USAGE</literal>.
+        When specifying a type by name rather than by OID, the allowed input
+        is the same as for the <type>regtype</type> data type (see
+        <xref linkend="datatype-oid"/>).
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_has_role</primary>
+        </indexterm>
+        <function>pg_has_role</function> (
+          <optional> <parameter>user</parameter> <type>name</type> or <type>oid</type>, </optional>
+          <parameter>role</parameter> <type>text</type> or <type>oid</type>,
+          <parameter>privilege</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does user have privilege for role?
+        Allowable privilege types are
+        <literal>MEMBER</literal>, <literal>USAGE</literal>,
+        and <literal>SET</literal>.
+        <literal>MEMBER</literal> denotes direct or indirect membership in
+        the role without regard to what specific privileges may be conferred.
+        <literal>USAGE</literal> denotes whether the privileges of the role
+        are immediately available without doing <command>SET ROLE</command>,
+        while <literal>SET</literal> denotes whether it is possible to change
+        to the role using the <literal>SET ROLE</literal> command.
+        <literal>WITH ADMIN OPTION</literal> or <literal>WITH GRANT
+        OPTION</literal> can be added to any of these privilege types to
+        test whether the <literal>ADMIN</literal> privilege is held (all
+        six spellings test the same thing).
+        This function does not allow the special case of
+        setting <parameter>user</parameter> to <literal>public</literal>,
+        because the PUBLIC pseudo-role can never be a member of real roles.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>row_security_active</primary>
+        </indexterm>
+        <function>row_security_active</function> (
+          <parameter>table</parameter> <type>text</type> or <type>oid</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is row-level security active for the specified table in the context of
+        the current user and current environment?
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <para>
+   <xref linkend="functions-aclitem-op-table"/> shows the operators
+   available for the <type>aclitem</type> type, which is the catalog
+   representation of access privileges.  See <xref linkend="ddl-priv"/>
+   for information about how to read access privilege values.
+  </para>
+
+    <table id="functions-aclitem-op-table">
+     <title><type>aclitem</type> Operators</title>
+     <tgroup cols="1">
+      <thead>
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         Operator
+        </para>
+        <para>
+         Description
+        </para>
+        <para>
+         Example(s)
+        </para></entry>
+       </row>
+      </thead>
+
+      <tbody>
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>aclitemeq</primary>
+         </indexterm>
+         <type>aclitem</type> <literal>=</literal> <type>aclitem</type>
+         <returnvalue>boolean</returnvalue>
+        </para>
+        <para>
+         Are <type>aclitem</type>s equal?  (Notice that
+         type <type>aclitem</type> lacks the usual set of comparison
+         operators; it has only equality.  In turn, <type>aclitem</type>
+         arrays can only be compared for equality.)
+        </para>
+        <para>
+         <literal>'calvin=r*w/hobbes'::aclitem = 'calvin=r*w*/hobbes'::aclitem</literal>
+         <returnvalue>f</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <indexterm>
+          <primary>aclcontains</primary>
+         </indexterm>
+         <type>aclitem[]</type> <literal>@&gt;</literal> <type>aclitem</type>
+         <returnvalue>boolean</returnvalue>
+        </para>
+        <para>
+         Does array contain the specified privileges?  (This is true if there
+         is an array entry that matches the <type>aclitem</type>'s grantee and
+         grantor, and has at least the specified set of privileges.)
+        </para>
+        <para>
+         <literal>'{calvin=r*w/hobbes,hobbes=r*w*/postgres}'::aclitem[] @&gt; 'calvin=r*/hobbes'::aclitem</literal>
+         <returnvalue>t</returnvalue>
+        </para></entry>
+       </row>
+
+       <row>
+        <entry role="func_table_entry"><para role="func_signature">
+         <type>aclitem[]</type> <literal>~</literal> <type>aclitem</type>
+         <returnvalue>boolean</returnvalue>
+        </para>
+        <para>
+         This is a deprecated alias for <literal>@&gt;</literal>.
+        </para>
+        <para>
+         <literal>'{calvin=r*w/hobbes,hobbes=r*w*/postgres}'::aclitem[] ~ 'calvin=r*/hobbes'::aclitem</literal>
+         <returnvalue>t</returnvalue>
+        </para></entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+   <para>
+    <xref linkend="functions-aclitem-fn-table"/> shows some additional
+    functions to manage the <type>aclitem</type> type.
+   </para>
+
+   <table id="functions-aclitem-fn-table">
+    <title><type>aclitem</type> Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>acldefault</primary>
+        </indexterm>
+        <function>acldefault</function> (
+          <parameter>type</parameter> <type>"char"</type>,
+          <parameter>ownerId</parameter> <type>oid</type> )
+        <returnvalue>aclitem[]</returnvalue>
+       </para>
+       <para>
+        Constructs an <type>aclitem</type> array holding the default access
+        privileges for an object of type <parameter>type</parameter> belonging
+        to the role with OID <parameter>ownerId</parameter>.  This represents
+        the access privileges that will be assumed when an object's
+        <acronym>ACL</acronym> entry is null. (The default access privileges
+        are described in <xref linkend="ddl-priv"/>.)
+        The <parameter>type</parameter> parameter must be one of
+        'c' for <literal>COLUMN</literal>,
+        'r' for <literal>TABLE</literal> and table-like objects,
+        's' for <literal>SEQUENCE</literal>,
+        'd' for <literal>DATABASE</literal>,
+        'f' for <literal>FUNCTION</literal> or <literal>PROCEDURE</literal>,
+        'l' for <literal>LANGUAGE</literal>,
+        'L' for <literal>LARGE OBJECT</literal>,
+        'n' for <literal>SCHEMA</literal>,
+        'p' for <literal>PARAMETER</literal>,
+        't' for <literal>TABLESPACE</literal>,
+        'F' for <literal>FOREIGN DATA WRAPPER</literal>,
+        'S' for <literal>FOREIGN SERVER</literal>,
+        or
+        'T' for <literal>TYPE</literal> or <literal>DOMAIN</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>aclexplode</primary>
+        </indexterm>
+        <function>aclexplode</function> ( <type>aclitem[]</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>grantor</parameter> <type>oid</type>,
+        <parameter>grantee</parameter> <type>oid</type>,
+        <parameter>privilege_type</parameter> <type>text</type>,
+        <parameter>is_grantable</parameter> <type>boolean</type> )
+       </para>
+       <para>
+        Returns the <type>aclitem</type> array as a set of rows.
+        If the grantee is the pseudo-role PUBLIC, it is represented by zero in
+        the <parameter>grantee</parameter> column.  Each granted privilege is
+        represented as <literal>SELECT</literal>, <literal>INSERT</literal>,
+        etc (see <xref linkend="privilege-abbrevs-table"/> for a full list).
+        Note that each privilege is broken out as a separate row, so
+        only one keyword appears in the <parameter>privilege_type</parameter>
+        column.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>makeaclitem</primary>
+        </indexterm>
+        <function>makeaclitem</function> (
+          <parameter>grantee</parameter> <type>oid</type>,
+          <parameter>grantor</parameter> <type>oid</type>,
+          <parameter>privileges</parameter> <type>text</type>,
+          <parameter>is_grantable</parameter> <type>boolean</type> )
+        <returnvalue>aclitem</returnvalue>
+       </para>
+       <para>
+        Constructs an <type>aclitem</type> with the given properties.
+        <parameter>privileges</parameter> is a comma-separated list of
+        privilege names such as <literal>SELECT</literal>,
+        <literal>INSERT</literal>, etc, all of which are set in the
+        result.  (Case of the privilege string is not significant, and
+        extra whitespace is allowed between but not within privilege
+        names.)
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  </sect2>
+
+  <sect2 id="functions-info-schema">
+   <title>Schema Visibility Inquiry Functions</title>
+
+  <para>
+   <xref linkend="functions-info-schema-table"/> shows functions that
+   determine whether a certain object is <firstterm>visible</firstterm> in the
+   current schema search path.
+   For example, a table is said to be visible if its
+   containing schema is in the search path and no table of the same
+   name appears earlier in the search path.  This is equivalent to the
+   statement that the table can be referenced by name without explicit
+   schema qualification.  Thus, to list the names of all visible tables:
+<programlisting>
+SELECT relname FROM pg_class WHERE pg_table_is_visible(oid);
+</programlisting>
+   For functions and operators, an object in the search path is said to be
+   visible if there is no object of the same name <emphasis>and argument data
+   type(s)</emphasis> earlier in the path.  For operator classes and families,
+   both the name and the associated index access method are considered.
+  </para>
+
+   <indexterm>
+    <primary>search path</primary>
+    <secondary>object visibility</secondary>
+   </indexterm>
+
+   <table id="functions-info-schema-table">
+    <title>Schema Visibility Inquiry Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_collation_is_visible</primary>
+        </indexterm>
+        <function>pg_collation_is_visible</function> ( <parameter>collation</parameter> <type>oid</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is collation visible in search path?
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_conversion_is_visible</primary>
+        </indexterm>
+        <function>pg_conversion_is_visible</function> ( <parameter>conversion</parameter> <type>oid</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is conversion visible in search path?
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_function_is_visible</primary>
+        </indexterm>
+        <function>pg_function_is_visible</function> ( <parameter>function</parameter> <type>oid</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is function visible in search path?
+        (This also works for procedures and aggregates.)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_opclass_is_visible</primary>
+        </indexterm>
+        <function>pg_opclass_is_visible</function> ( <parameter>opclass</parameter> <type>oid</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is operator class visible in search path?
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_operator_is_visible</primary>
+        </indexterm>
+        <function>pg_operator_is_visible</function> ( <parameter>operator</parameter> <type>oid</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is operator visible in search path?
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_opfamily_is_visible</primary>
+        </indexterm>
+        <function>pg_opfamily_is_visible</function> ( <parameter>opclass</parameter> <type>oid</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is operator family visible in search path?
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_statistics_obj_is_visible</primary>
+        </indexterm>
+        <function>pg_statistics_obj_is_visible</function> ( <parameter>stat</parameter> <type>oid</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is statistics object visible in search path?
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_table_is_visible</primary>
+        </indexterm>
+        <function>pg_table_is_visible</function> ( <parameter>table</parameter> <type>oid</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is table visible in search path?
+        (This works for all types of relations, including views, materialized
+        views, indexes, sequences and foreign tables.)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_ts_config_is_visible</primary>
+        </indexterm>
+        <function>pg_ts_config_is_visible</function> ( <parameter>config</parameter> <type>oid</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is text search configuration visible in search path?
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_ts_dict_is_visible</primary>
+        </indexterm>
+        <function>pg_ts_dict_is_visible</function> ( <parameter>dict</parameter> <type>oid</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is text search dictionary visible in search path?
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_ts_parser_is_visible</primary>
+        </indexterm>
+        <function>pg_ts_parser_is_visible</function> ( <parameter>parser</parameter> <type>oid</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is text search parser visible in search path?
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_ts_template_is_visible</primary>
+        </indexterm>
+        <function>pg_ts_template_is_visible</function> ( <parameter>template</parameter> <type>oid</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is text search template visible in search path?
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_type_is_visible</primary>
+        </indexterm>
+        <function>pg_type_is_visible</function> ( <parameter>type</parameter> <type>oid</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is type (or domain) visible in search path?
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    All these functions require object OIDs to identify the object to be
+    checked.  If you want to test an object by name, it is convenient to use
+    the OID alias types (<type>regclass</type>, <type>regtype</type>,
+    <type>regprocedure</type>, <type>regoperator</type>, <type>regconfig</type>,
+    or <type>regdictionary</type>),
+    for example:
+<programlisting>
+SELECT pg_type_is_visible('myschema.widget'::regtype);
+</programlisting>
+    Note that it would not make much sense to test a non-schema-qualified
+    type name in this way &mdash; if the name can be recognized at all, it must be visible.
+   </para>
+
+  </sect2>
+
+  <sect2 id="functions-info-catalog">
+   <title>System Catalog Information Functions</title>
+
+  <para>
+   <xref linkend="functions-info-catalog-table"/> lists functions that
+   extract information from the system catalogs.
+  </para>
+
+   <table id="functions-info-catalog-table">
+    <title>System Catalog Information Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry id="format-type" xreflabel="format_type" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>format_type</primary>
+        </indexterm>
+        <function>format_type</function> ( <parameter>type</parameter> <type>oid</type>, <parameter>typemod</parameter> <type>integer</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the SQL name for a data type that is identified by its type
+        OID and possibly a type modifier.  Pass NULL for the type modifier if
+        no specific modifier is known.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_basetype</primary>
+        </indexterm>
+        <function>pg_basetype</function> ( <type>regtype</type> )
+        <returnvalue>regtype</returnvalue>
+       </para>
+       <para>
+        Returns the OID of the base type of a domain identified by its
+        type OID.  If the argument is the OID of a non-domain type,
+        returns the argument as-is.  Returns NULL if the argument is
+        not a valid type OID.  If there's a chain of domain dependencies,
+        it will recurse until finding the base type.
+       </para>
+       <para>
+        Assuming <literal>CREATE DOMAIN mytext AS text</literal>:
+       </para>
+       <para>
+        <literal>pg_basetype('mytext'::regtype)</literal>
+        <returnvalue>text</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="pg-char-to-encoding" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_char_to_encoding</primary>
+        </indexterm>
+        <function>pg_char_to_encoding</function> ( <parameter>encoding</parameter> <type>name</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Converts the supplied encoding name into an integer representing the
+        internal identifier used in some system catalog tables.
+        Returns <literal>-1</literal> if an unknown encoding name is provided.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="pg-encoding-to-char" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_encoding_to_char</primary>
+        </indexterm>
+        <function>pg_encoding_to_char</function> ( <parameter>encoding</parameter> <type>integer</type> )
+        <returnvalue>name</returnvalue>
+       </para>
+       <para>
+        Converts the integer used as the internal identifier of an encoding in some
+        system catalog tables into a human-readable string.
+        Returns an empty string if an invalid encoding number is provided.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_catalog_foreign_keys</primary>
+        </indexterm>
+        <function>pg_get_catalog_foreign_keys</function> ()
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>fktable</parameter> <type>regclass</type>,
+          <parameter>fkcols</parameter> <type>text[]</type>,
+          <parameter>pktable</parameter> <type>regclass</type>,
+          <parameter>pkcols</parameter> <type>text[]</type>,
+          <parameter>is_array</parameter> <type>boolean</type>,
+          <parameter>is_opt</parameter> <type>boolean</type> )
+       </para>
+       <para>
+        Returns a set of records describing the foreign key relationships
+        that exist within the <productname>PostgreSQL</productname> system
+        catalogs.
+        The <parameter>fktable</parameter> column contains the name of the
+        referencing catalog, and the <parameter>fkcols</parameter> column
+        contains the name(s) of the referencing column(s).  Similarly,
+        the <parameter>pktable</parameter> column contains the name of the
+        referenced catalog, and the <parameter>pkcols</parameter> column
+        contains the name(s) of the referenced column(s).
+        If <parameter>is_array</parameter> is true, the last referencing
+        column is an array, each of whose elements should match some entry
+        in the referenced catalog.
+        If <parameter>is_opt</parameter> is true, the referencing column(s)
+        are allowed to contain zeroes instead of a valid reference.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_constraintdef</primary>
+        </indexterm>
+        <function>pg_get_constraintdef</function> ( <parameter>constraint</parameter> <type>oid</type> <optional>, <parameter>pretty</parameter> <type>boolean</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Reconstructs the creating command for a constraint.
+        (This is a decompiled reconstruction, not the original text
+        of the command.)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_expr</primary>
+        </indexterm>
+        <function>pg_get_expr</function> ( <parameter>expr</parameter> <type>pg_node_tree</type>, <parameter>relation</parameter> <type>oid</type> <optional>, <parameter>pretty</parameter> <type>boolean</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Decompiles the internal form of an expression stored in the system
+        catalogs, such as the default value for a column.  If the expression
+        might contain Vars, specify the OID of the relation they refer to as
+        the second parameter; if no Vars are expected, passing zero is
+        sufficient.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_functiondef</primary>
+        </indexterm>
+        <function>pg_get_functiondef</function> ( <parameter>func</parameter> <type>oid</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Reconstructs the creating command for a function or procedure.
+        (This is a decompiled reconstruction, not the original text
+        of the command.)
+        The result is a complete <command>CREATE OR REPLACE FUNCTION</command>
+        or <command>CREATE OR REPLACE PROCEDURE</command> statement.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_function_arguments</primary>
+        </indexterm>
+        <function>pg_get_function_arguments</function> ( <parameter>func</parameter> <type>oid</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Reconstructs the argument list of a function or procedure, in the form
+        it would need to appear in within <command>CREATE FUNCTION</command>
+        (including default values).
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_function_identity_arguments</primary>
+        </indexterm>
+        <function>pg_get_function_identity_arguments</function> ( <parameter>func</parameter> <type>oid</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Reconstructs the argument list necessary to identify a function or
+        procedure, in the form it would need to appear in within commands such
+        as <command>ALTER FUNCTION</command>.  This form omits default values.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_function_result</primary>
+        </indexterm>
+        <function>pg_get_function_result</function> ( <parameter>func</parameter> <type>oid</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Reconstructs the <literal>RETURNS</literal> clause of a function, in
+        the form it would need to appear in within <command>CREATE
+        FUNCTION</command>.  Returns <literal>NULL</literal> for a procedure.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_indexdef</primary>
+        </indexterm>
+        <function>pg_get_indexdef</function> ( <parameter>index</parameter> <type>oid</type> <optional>, <parameter>column</parameter> <type>integer</type>, <parameter>pretty</parameter> <type>boolean</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Reconstructs the creating command for an index.
+        (This is a decompiled reconstruction, not the original text
+        of the command.)  If <parameter>column</parameter> is supplied and is
+        not zero, only the definition of that column is reconstructed.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_keywords</primary>
+        </indexterm>
+        <function>pg_get_keywords</function> ()
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>word</parameter> <type>text</type>,
+        <parameter>catcode</parameter> <type>"char"</type>,
+        <parameter>barelabel</parameter> <type>boolean</type>,
+        <parameter>catdesc</parameter> <type>text</type>,
+        <parameter>baredesc</parameter> <type>text</type> )
+       </para>
+       <para>
+        Returns a set of records describing the SQL keywords recognized by the
+        server.  The <parameter>word</parameter> column contains the
+        keyword.  The <parameter>catcode</parameter> column contains a
+        category code: <literal>U</literal> for an unreserved
+        keyword, <literal>C</literal> for a keyword that can be a column
+        name, <literal>T</literal> for a keyword that can be a type or
+        function name, or <literal>R</literal> for a fully reserved keyword.
+        The <parameter>barelabel</parameter> column
+        contains <literal>true</literal> if the keyword can be used as
+        a <quote>bare</quote> column label in <command>SELECT</command> lists,
+        or <literal>false</literal> if it can only be used
+        after <literal>AS</literal>.
+        The <parameter>catdesc</parameter> column contains a
+        possibly-localized string describing the keyword's category.
+        The <parameter>baredesc</parameter> column contains a
+        possibly-localized string describing the keyword's column label status.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_partkeydef</primary>
+        </indexterm>
+        <function>pg_get_partkeydef</function> ( <parameter>table</parameter> <type>oid</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Reconstructs the definition of a partitioned table's partition
+        key, in the form it would have in the <literal>PARTITION
+        BY</literal> clause of <command>CREATE TABLE</command>.
+        (This is a decompiled reconstruction, not the original text
+        of the command.)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_ruledef</primary>
+        </indexterm>
+        <function>pg_get_ruledef</function> ( <parameter>rule</parameter> <type>oid</type> <optional>, <parameter>pretty</parameter> <type>boolean</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Reconstructs the creating command for a rule.
+        (This is a decompiled reconstruction, not the original text
+        of the command.)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_serial_sequence</primary>
+        </indexterm>
+        <function>pg_get_serial_sequence</function> ( <parameter>table</parameter> <type>text</type>, <parameter>column</parameter> <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the name of the sequence associated with a column,
+        or NULL if no sequence is associated with the column.
+        If the column is an identity column, the associated sequence is the
+        sequence internally created for that column.
+        For columns created using one of the serial types
+        (<type>serial</type>, <type>smallserial</type>, <type>bigserial</type>),
+        it is the sequence created for that serial column definition.
+        In the latter case, the association can be modified or removed
+        with <command>ALTER SEQUENCE OWNED BY</command>.
+        (This function probably should have been
+        called <function>pg_get_owned_sequence</function>; its current name
+        reflects the fact that it has historically been used with serial-type
+        columns.)  The first parameter is a table name with optional
+        schema, and the second parameter is a column name.  Because the first
+        parameter potentially contains both schema and table names, it is
+        parsed per usual SQL rules, meaning it is lower-cased by default.
+        The second parameter, being just a column name, is treated literally
+        and so has its case preserved.  The result is suitably formatted
+        for passing to the sequence functions (see
+        <xref linkend="functions-sequence"/>).
+       </para>
+       <para>
+        A typical use is in reading the current value of the sequence for an
+        identity or serial column, for example:
+<programlisting>
+SELECT currval(pg_get_serial_sequence('sometable', 'id'));
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_statisticsobjdef</primary>
+        </indexterm>
+        <function>pg_get_statisticsobjdef</function> ( <parameter>statobj</parameter> <type>oid</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Reconstructs the creating command for an extended statistics object.
+        (This is a decompiled reconstruction, not the original text
+        of the command.)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_triggerdef</primary>
+        </indexterm>
+<function>pg_get_triggerdef</function> ( <parameter>trigger</parameter> <type>oid</type> <optional>, <parameter>pretty</parameter> <type>boolean</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Reconstructs the creating command for a trigger.
+        (This is a decompiled reconstruction, not the original text
+        of the command.)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_userbyid</primary>
+        </indexterm>
+        <function>pg_get_userbyid</function> ( <parameter>role</parameter> <type>oid</type> )
+        <returnvalue>name</returnvalue>
+       </para>
+       <para>
+        Returns a role's name given its OID.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_viewdef</primary>
+        </indexterm>
+        <function>pg_get_viewdef</function> ( <parameter>view</parameter> <type>oid</type> <optional>, <parameter>pretty</parameter> <type>boolean</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Reconstructs the underlying <command>SELECT</command> command for a
+        view or materialized view.  (This is a decompiled reconstruction, not
+        the original text of the command.)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>pg_get_viewdef</function> ( <parameter>view</parameter> <type>oid</type>, <parameter>wrap_column</parameter> <type>integer</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Reconstructs the underlying <command>SELECT</command> command for a
+        view or materialized view.  (This is a decompiled reconstruction, not
+        the original text of the command.)  In this form of the function,
+        pretty-printing is always enabled, and long lines are wrapped to try
+        to keep them shorter than the specified number of columns.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>pg_get_viewdef</function> ( <parameter>view</parameter> <type>text</type> <optional>, <parameter>pretty</parameter> <type>boolean</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Reconstructs the underlying <command>SELECT</command> command for a
+        view or materialized view, working from a textual name for the view
+        rather than its OID.  (This is deprecated; use the OID variant
+        instead.)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_index_column_has_property</primary>
+        </indexterm>
+        <function>pg_index_column_has_property</function> ( <parameter>index</parameter> <type>regclass</type>, <parameter>column</parameter> <type>integer</type>, <parameter>property</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Tests whether an index column has the named property.
+        Common index column properties are listed in
+        <xref linkend="functions-info-index-column-props"/>.
+        (Note that extension access methods can define additional property
+        names for their indexes.)
+        <literal>NULL</literal> is returned if the property name is not known
+        or does not apply to the particular object, or if the OID or column
+        number does not identify a valid object.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_index_has_property</primary>
+        </indexterm>
+        <function>pg_index_has_property</function> ( <parameter>index</parameter> <type>regclass</type>, <parameter>property</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Tests whether an index has the named property.
+        Common index properties are listed in
+        <xref linkend="functions-info-index-props"/>.
+        (Note that extension access methods can define additional property
+        names for their indexes.)
+        <literal>NULL</literal> is returned if the property name is not known
+        or does not apply to the particular object, or if the OID does not
+        identify a valid object.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_indexam_has_property</primary>
+        </indexterm>
+        <function>pg_indexam_has_property</function> ( <parameter>am</parameter> <type>oid</type>, <parameter>property</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Tests whether an index access method has the named property.
+        Access method properties are listed in
+        <xref linkend="functions-info-indexam-props"/>.
+        <literal>NULL</literal> is returned if the property name is not known
+        or does not apply to the particular object, or if the OID does not
+        identify a valid object.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_options_to_table</primary>
+        </indexterm>
+        <function>pg_options_to_table</function> ( <parameter>options_array</parameter> <type>text[]</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>option_name</parameter> <type>text</type>,
+        <parameter>option_value</parameter> <type>text</type> )
+       </para>
+       <para>
+        Returns the set of storage options represented by a value from
+        <structname>pg_class</structname>.<structfield>reloptions</structfield> or
+        <structname>pg_attribute</structname>.<structfield>attoptions</structfield>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_settings_get_flags</primary>
+        </indexterm>
+        <function>pg_settings_get_flags</function> ( <parameter>guc</parameter> <type>text</type> )
+        <returnvalue>text[]</returnvalue>
+       </para>
+       <para>
+        Returns an array of the flags associated with the given GUC, or
+        <literal>NULL</literal> if it does not exist. The result is
+        an empty array if the GUC exists but there are no flags to show.
+        Only the most useful flags listed in
+        <xref linkend="functions-pg-settings-flags"/> are exposed.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_tablespace_databases</primary>
+        </indexterm>
+        <function>pg_tablespace_databases</function> ( <parameter>tablespace</parameter> <type>oid</type> )
+        <returnvalue>setof oid</returnvalue>
+       </para>
+       <para>
+        Returns the set of OIDs of databases that have objects stored in the
+        specified tablespace.  If this function returns any rows, the
+        tablespace is not empty and cannot be dropped.  To identify the specific
+        objects populating the tablespace, you will need to connect to the
+        database(s) identified by <function>pg_tablespace_databases</function>
+        and query their <structname>pg_class</structname> catalogs.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_tablespace_location</primary>
+        </indexterm>
+        <function>pg_tablespace_location</function> ( <parameter>tablespace</parameter> <type>oid</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the file system path that this tablespace is located in.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_typeof</primary>
+        </indexterm>
+        <function>pg_typeof</function> ( <type>"any"</type> )
+        <returnvalue>regtype</returnvalue>
+       </para>
+       <para>
+        Returns the OID of the data type of the value that is passed to it.
+        This can be helpful for troubleshooting or dynamically constructing
+        SQL queries.  The function is declared as
+        returning <type>regtype</type>, which is an OID alias type (see
+        <xref linkend="datatype-oid"/>); this means that it is the same as an
+        OID for comparison purposes but displays as a type name.
+       </para>
+       <para>
+        <literal>pg_typeof(33)</literal>
+        <returnvalue>integer</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>COLLATION FOR</primary>
+        </indexterm>
+        <function>COLLATION FOR</function> ( <type>"any"</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the name of the collation of the value that is passed to it.
+        The value is quoted and schema-qualified if necessary.  If no
+        collation was derived for the argument expression,
+        then <literal>NULL</literal> is returned.  If the argument is not of a
+        collatable data type, then an error is raised.
+       </para>
+       <para>
+        <literal>collation for ('foo'::text)</literal>
+        <returnvalue>"default"</returnvalue>
+       </para>
+       <para>
+        <literal>collation for ('foo' COLLATE "de_DE")</literal>
+        <returnvalue>"de_DE"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_regclass</primary>
+        </indexterm>
+        <function>to_regclass</function> ( <type>text</type> )
+        <returnvalue>regclass</returnvalue>
+       </para>
+       <para>
+        Translates a textual relation name to its OID.  A similar result is
+        obtained by casting the string to type <type>regclass</type> (see
+        <xref linkend="datatype-oid"/>); however, this function will return
+        <literal>NULL</literal> rather than throwing an error if the name is
+        not found.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_regdatabase</primary>
+        </indexterm>
+        <function>to_regdatabase</function> ( <type>text</type> )
+        <returnvalue>regdatabase</returnvalue>
+       </para>
+       <para>
+        Translates a textual database name to its OID.  A similar result is
+        obtained by casting the string to type <type>regdatabase</type> (see
+        <xref linkend="datatype-oid"/>); however, this function will return
+        <literal>NULL</literal> rather than throwing an error if the name is
+        not found.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_regcollation</primary>
+        </indexterm>
+        <function>to_regcollation</function> ( <type>text</type> )
+        <returnvalue>regcollation</returnvalue>
+       </para>
+       <para>
+        Translates a textual collation name to its OID.  A similar result is
+        obtained by casting the string to type <type>regcollation</type> (see
+        <xref linkend="datatype-oid"/>); however, this function will return
+        <literal>NULL</literal> rather than throwing an error if the name is
+        not found.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_regnamespace</primary>
+        </indexterm>
+        <function>to_regnamespace</function> ( <type>text</type> )
+        <returnvalue>regnamespace</returnvalue>
+       </para>
+       <para>
+        Translates a textual schema name to its OID.  A similar result is
+        obtained by casting the string to type <type>regnamespace</type> (see
+        <xref linkend="datatype-oid"/>); however, this function will return
+        <literal>NULL</literal> rather than throwing an error if the name is
+        not found.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_regoper</primary>
+        </indexterm>
+        <function>to_regoper</function> ( <type>text</type> )
+        <returnvalue>regoper</returnvalue>
+       </para>
+       <para>
+        Translates a textual operator name to its OID.  A similar result is
+        obtained by casting the string to type <type>regoper</type> (see
+        <xref linkend="datatype-oid"/>); however, this function will return
+        <literal>NULL</literal> rather than throwing an error if the name is
+        not found or is ambiguous.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_regoperator</primary>
+        </indexterm>
+        <function>to_regoperator</function> ( <type>text</type> )
+        <returnvalue>regoperator</returnvalue>
+       </para>
+       <para>
+        Translates a textual operator name (with parameter types) to its OID.  A similar result is
+        obtained by casting the string to type <type>regoperator</type> (see
+        <xref linkend="datatype-oid"/>); however, this function will return
+        <literal>NULL</literal> rather than throwing an error if the name is
+        not found.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_regproc</primary>
+        </indexterm>
+        <function>to_regproc</function> ( <type>text</type> )
+        <returnvalue>regproc</returnvalue>
+       </para>
+       <para>
+        Translates a textual function or procedure name to its OID.  A similar result is
+        obtained by casting the string to type <type>regproc</type> (see
+        <xref linkend="datatype-oid"/>); however, this function will return
+        <literal>NULL</literal> rather than throwing an error if the name is
+        not found or is ambiguous.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_regprocedure</primary>
+        </indexterm>
+        <function>to_regprocedure</function> ( <type>text</type> )
+        <returnvalue>regprocedure</returnvalue>
+       </para>
+       <para>
+        Translates a textual function or procedure name (with argument types) to its OID.  A similar result is
+        obtained by casting the string to type <type>regprocedure</type> (see
+        <xref linkend="datatype-oid"/>); however, this function will return
+        <literal>NULL</literal> rather than throwing an error if the name is
+        not found.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_regrole</primary>
+        </indexterm>
+        <function>to_regrole</function> ( <type>text</type> )
+        <returnvalue>regrole</returnvalue>
+       </para>
+       <para>
+        Translates a textual role name to its OID.  A similar result is
+        obtained by casting the string to type <type>regrole</type> (see
+        <xref linkend="datatype-oid"/>); however, this function will return
+        <literal>NULL</literal> rather than throwing an error if the name is
+        not found.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry id="to-regtype" xreflabel="to_regtype" role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_regtype</primary>
+        </indexterm>
+        <function>to_regtype</function> ( <type>text</type> )
+        <returnvalue>regtype</returnvalue>
+       </para>
+       <para>
+        Parses a string of text, extracts a potential type name from it,
+        and translates that name into a type OID.  A syntax error in the
+        string will result in an error; but if the string is a
+        syntactically valid type name that happens not to be found in the
+        catalogs, the result is <literal>NULL</literal>.  A similar result
+        is obtained by casting the string to type <type>regtype</type>
+        (see <xref linkend="datatype-oid"/>), except that that will throw
+        error for name not found.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_regtypemod</primary>
+        </indexterm>
+        <function>to_regtypemod</function> ( <type>text</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Parses a string of text, extracts a potential type name from it,
+        and translates its type modifier, if any.  A syntax error in the
+        string will result in an error; but if the string is a
+        syntactically valid type name that happens not to be found in the
+        catalogs, the result is <literal>NULL</literal>.  The result is
+        <literal>-1</literal> if no type modifier is present.
+       </para>
+       <para>
+        <function>to_regtypemod</function> can be combined with
+        <xref linkend="to-regtype"/> to produce appropriate inputs for
+        <xref linkend="format-type"/>, allowing a string representing a
+        type name to be canonicalized.
+       </para>
+       <para>
+        <literal>format_type(to_regtype('varchar(32)'), to_regtypemod('varchar(32)'))</literal>
+        <returnvalue>character varying(32)</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <para>
+   Most of the functions that reconstruct (decompile) database objects
+   have an optional <parameter>pretty</parameter> flag, which
+   if <literal>true</literal> causes the result to
+   be <quote>pretty-printed</quote>.  Pretty-printing suppresses unnecessary
+   parentheses and adds whitespace for legibility.
+   The pretty-printed format is more readable, but the default format
+   is more likely to be interpreted the same way by future versions of
+   <productname>PostgreSQL</productname>; so avoid using pretty-printed output
+   for dump purposes.  Passing <literal>false</literal> for
+   the <parameter>pretty</parameter> parameter yields the same result as
+   omitting the parameter.
+  </para>
+
+  <table id="functions-info-index-column-props">
+   <title>Index Column Properties</title>
+   <tgroup cols="2">
+    <thead>
+     <row><entry>Name</entry><entry>Description</entry></row>
+    </thead>
+    <tbody>
+     <row>
+      <entry><literal>asc</literal></entry>
+      <entry>Does the column sort in ascending order on a forward scan?
+      </entry>
+     </row>
+     <row>
+      <entry><literal>desc</literal></entry>
+      <entry>Does the column sort in descending order on a forward scan?
+      </entry>
+     </row>
+     <row>
+      <entry><literal>nulls_first</literal></entry>
+      <entry>Does the column sort with nulls first on a forward scan?
+      </entry>
+     </row>
+     <row>
+      <entry><literal>nulls_last</literal></entry>
+      <entry>Does the column sort with nulls last on a forward scan?
+      </entry>
+     </row>
+     <row>
+      <entry><literal>orderable</literal></entry>
+      <entry>Does the column possess any defined sort ordering?
+      </entry>
+     </row>
+     <row>
+      <entry><literal>distance_orderable</literal></entry>
+      <entry>Can the column be scanned in order by a <quote>distance</quote>
+      operator, for example <literal>ORDER BY col &lt;-&gt; constant</literal> ?
+      </entry>
+     </row>
+     <row>
+      <entry><literal>returnable</literal></entry>
+      <entry>Can the column value be returned by an index-only scan?
+      </entry>
+     </row>
+     <row>
+      <entry><literal>search_array</literal></entry>
+      <entry>Does the column natively support <literal>col = ANY(array)</literal>
+      searches?
+      </entry>
+     </row>
+     <row>
+      <entry><literal>search_nulls</literal></entry>
+      <entry>Does the column support <literal>IS NULL</literal> and
+      <literal>IS NOT NULL</literal> searches?
+      </entry>
+     </row>
+    </tbody>
+   </tgroup>
+  </table>
+
+  <table id="functions-info-index-props">
+   <title>Index Properties</title>
+   <tgroup cols="2">
+    <thead>
+     <row><entry>Name</entry><entry>Description</entry></row>
+    </thead>
+    <tbody>
+     <row>
+      <entry><literal>clusterable</literal></entry>
+      <entry>Can the index be used in a <literal>CLUSTER</literal> command?
+      </entry>
+     </row>
+     <row>
+      <entry><literal>index_scan</literal></entry>
+      <entry>Does the index support plain (non-bitmap) scans?
+      </entry>
+     </row>
+     <row>
+      <entry><literal>bitmap_scan</literal></entry>
+      <entry>Does the index support bitmap scans?
+      </entry>
+     </row>
+     <row>
+      <entry><literal>backward_scan</literal></entry>
+      <entry>Can the scan direction be changed in mid-scan (to
+             support <literal>FETCH BACKWARD</literal> on a cursor without
+             needing materialization)?
+      </entry>
+     </row>
+    </tbody>
+   </tgroup>
+  </table>
+
+  <table id="functions-info-indexam-props">
+   <title>Index Access Method Properties</title>
+   <tgroup cols="2">
+    <thead>
+     <row><entry>Name</entry><entry>Description</entry></row>
+    </thead>
+    <tbody>
+     <row>
+      <entry><literal>can_order</literal></entry>
+      <entry>Does the access method support <literal>ASC</literal>,
+      <literal>DESC</literal> and related keywords in
+      <literal>CREATE INDEX</literal>?
+      </entry>
+     </row>
+     <row>
+      <entry><literal>can_unique</literal></entry>
+      <entry>Does the access method support unique indexes?
+      </entry>
+     </row>
+     <row>
+      <entry><literal>can_multi_col</literal></entry>
+      <entry>Does the access method support indexes with multiple columns?
+      </entry>
+     </row>
+     <row>
+      <entry><literal>can_exclude</literal></entry>
+      <entry>Does the access method support exclusion constraints?
+      </entry>
+     </row>
+     <row>
+      <entry><literal>can_include</literal></entry>
+      <entry>Does the access method support the <literal>INCLUDE</literal>
+        clause of <literal>CREATE INDEX</literal>?
+      </entry>
+     </row>
+    </tbody>
+   </tgroup>
+  </table>
+
+  <table id="functions-pg-settings-flags">
+   <title>GUC Flags</title>
+   <tgroup cols="2">
+    <thead>
+     <row><entry>Flag</entry><entry>Description</entry></row>
+    </thead>
+    <tbody>
+     <row>
+      <entry><literal>EXPLAIN</literal></entry>
+      <entry>Parameters with this flag are included in
+       <command>EXPLAIN (SETTINGS)</command> commands.
+      </entry>
+     </row>
+     <row>
+      <entry><literal>NO_SHOW_ALL</literal></entry>
+      <entry>Parameters with this flag are excluded from
+       <command>SHOW ALL</command> commands.
+      </entry>
+     </row>
+     <row>
+      <entry><literal>NO_RESET</literal></entry>
+      <entry>Parameters with this flag do not support
+      <command>RESET</command> commands.
+      </entry>
+     </row>
+     <row>
+      <entry><literal>NO_RESET_ALL</literal></entry>
+      <entry>Parameters with this flag are excluded from
+       <command>RESET ALL</command> commands.
+      </entry>
+     </row>
+     <row>
+      <entry><literal>NOT_IN_SAMPLE</literal></entry>
+      <entry>Parameters with this flag are not included in
+       <filename>postgresql.conf</filename> by default.
+      </entry>
+     </row>
+     <row>
+      <entry><literal>RUNTIME_COMPUTED</literal></entry>
+      <entry>Parameters with this flag are runtime-computed ones.
+      </entry>
+     </row>
+    </tbody>
+   </tgroup>
+  </table>
+
+  </sect2>
+
+  <sect2 id="functions-info-object">
+   <title>Object Information and Addressing Functions</title>
+
+  <para>
+   <xref linkend="functions-info-object-table"/> lists functions related to
+   database object identification and addressing.
+  </para>
+
+   <table id="functions-info-object-table">
+    <title>Object Information and Addressing Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_acl</primary>
+        </indexterm>
+        <function>pg_get_acl</function> ( <parameter>classid</parameter> <type>oid</type>, <parameter>objid</parameter> <type>oid</type>, <parameter>objsubid</parameter> <type>integer</type> )
+        <returnvalue>aclitem[]</returnvalue>
+       </para>
+       <para>
+        Returns the <acronym>ACL</acronym> for a database object, specified
+        by catalog OID, object OID and sub-object ID. This function returns
+        <literal>NULL</literal> values for undefined objects.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_describe_object</primary>
+        </indexterm>
+        <function>pg_describe_object</function> ( <parameter>classid</parameter> <type>oid</type>, <parameter>objid</parameter> <type>oid</type>, <parameter>objsubid</parameter> <type>integer</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns a textual description of a database object identified by
+        catalog OID, object OID, and sub-object ID (such as a column number
+        within a table; the sub-object ID is zero when referring to a whole
+        object).  This description is intended to be human-readable, and might
+        be translated, depending on server configuration.  This is especially
+        useful to determine the identity of an object referenced in the
+        <structname>pg_depend</structname> catalog. This function returns
+        <literal>NULL</literal> values for undefined objects.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_identify_object</primary>
+        </indexterm>
+        <function>pg_identify_object</function> ( <parameter>classid</parameter> <type>oid</type>, <parameter>objid</parameter> <type>oid</type>, <parameter>objsubid</parameter> <type>integer</type> )
+        <returnvalue>record</returnvalue>
+        ( <parameter>type</parameter> <type>text</type>,
+        <parameter>schema</parameter> <type>text</type>,
+        <parameter>name</parameter> <type>text</type>,
+        <parameter>identity</parameter> <type>text</type> )
+       </para>
+       <para>
+        Returns a row containing enough information to uniquely identify the
+        database object specified by catalog OID, object OID and sub-object
+        ID.
+        This information is intended to be machine-readable, and is never
+        translated.
+        <parameter>type</parameter> identifies the type of database object;
+        <parameter>schema</parameter> is the schema name that the object
+        belongs in, or <literal>NULL</literal> for object types that do not
+        belong to schemas;
+        <parameter>name</parameter> is the name of the object, quoted if
+        necessary, if the name (along with schema name, if pertinent) is
+        sufficient to uniquely identify the object,
+        otherwise <literal>NULL</literal>;
+        <parameter>identity</parameter> is the complete object identity, with
+        the precise format depending on object type, and each name within the
+        format being schema-qualified and quoted as necessary. Undefined
+        objects are identified with <literal>NULL</literal> values.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_identify_object_as_address</primary>
+        </indexterm>
+        <function>pg_identify_object_as_address</function> ( <parameter>classid</parameter> <type>oid</type>, <parameter>objid</parameter> <type>oid</type>, <parameter>objsubid</parameter> <type>integer</type> )
+        <returnvalue>record</returnvalue>
+        ( <parameter>type</parameter> <type>text</type>,
+        <parameter>object_names</parameter> <type>text[]</type>,
+        <parameter>object_args</parameter> <type>text[]</type> )
+       </para>
+       <para>
+        Returns a row containing enough information to uniquely identify the
+        database object specified by catalog OID, object OID and sub-object
+        ID.
+        The returned information is independent of the current server, that
+        is, it could be used to identify an identically named object in
+        another server.
+        <parameter>type</parameter> identifies the type of database object;
+        <parameter>object_names</parameter> and
+        <parameter>object_args</parameter>
+        are text arrays that together form a reference to the object.
+        These three values can be passed
+        to <function>pg_get_object_address</function> to obtain the internal
+        address of the object.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_object_address</primary>
+        </indexterm>
+        <function>pg_get_object_address</function> ( <parameter>type</parameter> <type>text</type>, <parameter>object_names</parameter> <type>text[]</type>, <parameter>object_args</parameter> <type>text[]</type> )
+        <returnvalue>record</returnvalue>
+        ( <parameter>classid</parameter> <type>oid</type>,
+        <parameter>objid</parameter> <type>oid</type>,
+        <parameter>objsubid</parameter> <type>integer</type> )
+       </para>
+       <para>
+        Returns a row containing enough information to uniquely identify the
+        database object specified by a type code and object name and argument
+        arrays.
+        The returned values are the ones that would be used in system catalogs
+        such as <structname>pg_depend</structname>; they can be passed to
+        other system functions such as <function>pg_describe_object</function>
+        or <function>pg_identify_object</function>.
+        <parameter>classid</parameter> is the OID of the system catalog
+        containing the object;
+        <parameter>objid</parameter> is the OID of the object itself, and
+        <parameter>objsubid</parameter> is the sub-object ID, or zero if none.
+        This function is the inverse
+        of <function>pg_identify_object_as_address</function>.
+        Undefined objects are identified with <literal>NULL</literal> values.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    <function>pg_get_acl</function> is useful for retrieving and inspecting
+    the privileges associated with database objects without looking at
+    specific catalogs. For example, to retrieve all the granted privileges
+    on objects in the current database:
+<programlisting>
+postgres=# SELECT
+    (pg_identify_object(s.classid,s.objid,s.objsubid)).*,
+    pg_catalog.pg_get_acl(s.classid,s.objid,s.objsubid) AS acl
+FROM pg_catalog.pg_shdepend AS s
+JOIN pg_catalog.pg_database AS d
+    ON d.datname = current_database() AND
+       d.oid = s.dbid
+JOIN pg_catalog.pg_authid AS a
+    ON a.oid = s.refobjid AND
+       s.refclassid = 'pg_authid'::regclass
+WHERE s.deptype = 'a';
+-[ RECORD 1 ]-----------------------------------------
+type     | table
+schema   | public
+name     | testtab
+identity | public.testtab
+acl      | {postgres=arwdDxtm/postgres,foo=r/postgres}
+</programlisting>
+   </para>
+
+  </sect2>
+
+  <sect2 id="functions-info-comment">
+   <title>Comment Information Functions</title>
+
+   <indexterm>
+    <primary>comment</primary>
+    <secondary sortas="database objects">about database objects</secondary>
+   </indexterm>
+
+   <para>
+    The functions shown in <xref linkend="functions-info-comment-table"/>
+    extract comments previously stored with the <xref linkend="sql-comment"/>
+    command.  A null value is returned if no
+    comment could be found for the specified parameters.
+   </para>
+
+   <table id="functions-info-comment-table">
+    <title>Comment Information Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>col_description</primary>
+        </indexterm>
+        <function>col_description</function> ( <parameter>table</parameter> <type>oid</type>, <parameter>column</parameter> <type>integer</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the comment for a table column, which is specified by the OID
+        of its table and its column number.
+        (<function>obj_description</function> cannot be used for table
+        columns, since columns do not have OIDs of their own.)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>obj_description</primary>
+        </indexterm>
+        <function>obj_description</function> ( <parameter>object</parameter> <type>oid</type>, <parameter>catalog</parameter> <type>name</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the comment for a database object specified by its OID and the
+        name of the containing system catalog.  For
+        example, <literal>obj_description(123456, 'pg_class')</literal> would
+        retrieve the comment for the table with OID 123456.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>obj_description</function> ( <parameter>object</parameter> <type>oid</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the comment for a database object specified by its OID alone.
+        This is <emphasis>deprecated</emphasis> since there is no guarantee
+        that OIDs are unique across different system catalogs; therefore, the
+        wrong comment might be returned.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>shobj_description</primary>
+        </indexterm>
+        <function>shobj_description</function> ( <parameter>object</parameter> <type>oid</type>, <parameter>catalog</parameter> <type>name</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the comment for a shared database object specified by its OID
+        and the name of the containing system catalog.  This is just
+        like <function>obj_description</function> except that it is used for
+        retrieving comments on shared objects (that is, databases, roles, and
+        tablespaces).  Some system catalogs are global to all databases within
+        each cluster, and the descriptions for objects in them are stored
+        globally as well.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  </sect2>
+
+  <sect2 id="functions-info-validity">
+   <title>Data Validity Checking Functions</title>
+
+   <para>
+    The functions shown in <xref linkend="functions-info-validity-table"/>
+    can be helpful for checking validity of proposed input data.
+   </para>
+
+   <table id="functions-info-validity-table">
+    <title>Data Validity Checking Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_input_is_valid</primary>
+        </indexterm>
+        <function>pg_input_is_valid</function> (
+          <parameter>string</parameter> <type>text</type>,
+          <parameter>type</parameter> <type>text</type>
+        )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Tests whether the given <parameter>string</parameter> is valid
+        input for the specified data type, returning true or false.
+       </para>
+       <para>
+        This function will only work as desired if the data type's input
+        function has been updated to report invalid input as
+        a <quote>soft</quote> error.  Otherwise, invalid input will abort
+        the transaction, just as if the string had been cast to the type
+        directly.
+        </para>
+        <para>
+         <literal>pg_input_is_valid('42', 'integer')</literal>
+         <returnvalue>t</returnvalue>
+        </para>
+        <para>
+         <literal>pg_input_is_valid('42000000000', 'integer')</literal>
+         <returnvalue>f</returnvalue>
+        </para>
+        <para>
+         <literal>pg_input_is_valid('1234.567', 'numeric(7,4)')</literal>
+         <returnvalue>f</returnvalue>
+       </para></entry>
+      </row>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_input_error_info</primary>
+        </indexterm>
+        <function>pg_input_error_info</function> (
+          <parameter>string</parameter> <type>text</type>,
+          <parameter>type</parameter> <type>text</type>
+        )
+        <returnvalue>record</returnvalue>
+        ( <parameter>message</parameter> <type>text</type>,
+        <parameter>detail</parameter> <type>text</type>,
+        <parameter>hint</parameter> <type>text</type>,
+        <parameter>sql_error_code</parameter> <type>text</type> )
+       </para>
+       <para>
+        Tests whether the given <parameter>string</parameter> is valid
+        input for the specified data type; if not, return the details of
+        the error that would have been thrown.  If the input is valid, the
+        results are NULL.  The inputs are the same as
+        for <function>pg_input_is_valid</function>.
+       </para>
+       <para>
+        This function will only work as desired if the data type's input
+        function has been updated to report invalid input as
+        a <quote>soft</quote> error.  Otherwise, invalid input will abort
+        the transaction, just as if the string had been cast to the type
+        directly.
+       </para>
+       <para>
+        <literal>SELECT * FROM pg_input_error_info('42000000000', 'integer')</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+                       message                        | detail | hint | sql_error_code
+------------------------------------------------------+--------+------+----------------
+ value "42000000000" is out of range for type integer |        |      | 22003
+</programlisting>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  </sect2>
+
+  <sect2 id="functions-info-snapshot">
+   <title>Transaction ID and Snapshot Information Functions</title>
+
+   <para>
+    The functions shown in <xref linkend="functions-pg-snapshot"/>
+    provide server transaction information in an exportable form.  The main
+    use of these functions is to determine which transactions were committed
+    between two snapshots.
+   </para>
+
+   <table id="functions-pg-snapshot">
+    <title>Transaction ID and Snapshot Information Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>age</primary>
+        </indexterm>
+        <function>age</function>  ( <type>xid</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the number of transactions between the supplied
+        transaction id and the current transaction counter.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>mxid_age</primary>
+        </indexterm>
+        <function>mxid_age</function>  ( <type>xid</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the number of multixacts IDs between the supplied
+        multixact ID and the current multixacts counter.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_current_xact_id</primary>
+        </indexterm>
+        <function>pg_current_xact_id</function> ()
+        <returnvalue>xid8</returnvalue>
+       </para>
+       <para>
+        Returns the current transaction's ID.  It will assign a new one if the
+        current transaction does not have one already (because it has not
+        performed any database updates);  see <xref
+        linkend="transaction-id"/> for details.  If executed in a
+        subtransaction, this will return the top-level transaction ID;
+        see <xref linkend="subxacts"/> for details.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_current_xact_id_if_assigned</primary>
+        </indexterm>
+        <function>pg_current_xact_id_if_assigned</function> ()
+        <returnvalue>xid8</returnvalue>
+       </para>
+       <para>
+        Returns the current transaction's ID, or <literal>NULL</literal> if no
+        ID is assigned yet.  (It's best to use this variant if the transaction
+        might otherwise be read-only, to avoid unnecessary consumption of an
+        XID.)
+        If executed in a subtransaction, this will return the top-level
+        transaction ID.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_xact_status</primary>
+        </indexterm>
+        <function>pg_xact_status</function> ( <type>xid8</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Reports the commit status of a recent transaction.
+        The result is one of <literal>in progress</literal>,
+        <literal>committed</literal>, or <literal>aborted</literal>,
+        provided that the transaction is recent enough that the system retains
+        the commit status of that transaction.
+        If it is old enough that no references to the transaction survive in
+        the system and the commit status information has been discarded, the
+        result is <literal>NULL</literal>.
+        Applications might use this function, for example, to determine
+        whether their transaction committed or aborted after the application
+        and database server become disconnected while
+        a <literal>COMMIT</literal> is in progress.
+        Note that prepared transactions are reported as <literal>in
+        progress</literal>; applications must check <link
+        linkend="view-pg-prepared-xacts"><structname>pg_prepared_xacts</structname></link>
+        if they need to determine whether a transaction ID belongs to a
+        prepared transaction.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_current_snapshot</primary>
+        </indexterm>
+        <function>pg_current_snapshot</function> ()
+        <returnvalue>pg_snapshot</returnvalue>
+       </para>
+       <para>
+        Returns a current <firstterm>snapshot</firstterm>, a data structure
+        showing which transaction IDs are now in-progress.
+        Only top-level transaction IDs are included in the snapshot;
+        subtransaction IDs are not shown;  see <xref linkend="subxacts"/>
+        for details.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_snapshot_xip</primary>
+        </indexterm>
+        <function>pg_snapshot_xip</function> ( <type>pg_snapshot</type> )
+        <returnvalue>setof xid8</returnvalue>
+       </para>
+       <para>
+        Returns the set of in-progress transaction IDs contained in a snapshot.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_snapshot_xmax</primary>
+        </indexterm>
+        <function>pg_snapshot_xmax</function> ( <type>pg_snapshot</type> )
+        <returnvalue>xid8</returnvalue>
+       </para>
+       <para>
+        Returns the <structfield>xmax</structfield> of a snapshot.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_snapshot_xmin</primary>
+        </indexterm>
+        <function>pg_snapshot_xmin</function> ( <type>pg_snapshot</type> )
+        <returnvalue>xid8</returnvalue>
+       </para>
+       <para>
+        Returns the <structfield>xmin</structfield> of a snapshot.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_visible_in_snapshot</primary>
+        </indexterm>
+        <function>pg_visible_in_snapshot</function> ( <type>xid8</type>, <type>pg_snapshot</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the given transaction ID <firstterm>visible</firstterm> according
+        to this snapshot (that is, was it completed before the snapshot was
+        taken)?  Note that this function will not give the correct answer for
+        a subtransaction ID (subxid);  see <xref linkend="subxacts"/> for
+        details.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_multixact_members</primary>
+        </indexterm>
+        <function>pg_get_multixact_members</function> ( <parameter>multixid</parameter> <type>xid</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>xid</parameter> <type>xid</type>,
+        <parameter>mode</parameter> <type>text</type> )
+       </para>
+       <para>
+        Returns the transaction ID and lock mode for each member of the
+        specified multixact ID.  The lock modes <literal>forupd</literal>,
+        <literal>fornokeyupd</literal>, <literal>sh</literal>, and
+        <literal>keysh</literal> correspond to the row-level locks
+        <literal>FOR UPDATE</literal>, <literal>FOR NO KEY UPDATE</literal>,
+        <literal>FOR SHARE</literal>, and <literal>FOR KEY SHARE</literal>,
+        respectively, as described in <xref linkend="locking-rows"/>.  Two
+        additional modes are specific to multixacts:
+        <literal>nokeyupd</literal>, used by updates that do not modify key
+        columns, and <literal>upd</literal>, used by updates or deletes that
+        modify key columns.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    The internal transaction ID type <type>xid</type> is 32 bits wide and
+    wraps around every 4 billion transactions.  However,
+    the functions shown in <xref linkend="functions-pg-snapshot"/>, except
+    <function>age</function>, <function>mxid_age</function>, and
+    <function>pg_get_multixact_members</function>, use a
+    64-bit type <type>xid8</type> that does not wrap around during the life
+    of an installation and can be converted to <type>xid</type> by casting if
+    required;  see <xref linkend="transaction-id"/> for details.
+    The data type <type>pg_snapshot</type> stores information about
+    transaction ID visibility at a particular moment in time.  Its components
+    are described in <xref linkend="functions-pg-snapshot-parts"/>.
+    <type>pg_snapshot</type>'s textual representation is
+    <literal><replaceable>xmin</replaceable>:<replaceable>xmax</replaceable>:<replaceable>xip_list</replaceable></literal>.
+    For example <literal>10:20:10,14,15</literal> means
+    <literal>xmin=10, xmax=20, xip_list=10, 14, 15</literal>.
+   </para>
+
+   <table id="functions-pg-snapshot-parts">
+    <title>Snapshot Components</title>
+    <tgroup cols="2">
+     <thead>
+      <row>
+       <entry>Name</entry>
+       <entry>Description</entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry><structfield>xmin</structfield></entry>
+       <entry>
+         Lowest transaction ID that was still active.  All transaction IDs
+         less than <structfield>xmin</structfield> are either committed and visible,
+         or rolled back and dead.
+       </entry>
+      </row>
+
+      <row>
+       <entry><structfield>xmax</structfield></entry>
+       <entry>
+         One past the highest completed transaction ID.  All transaction IDs
+         greater than or equal to <structfield>xmax</structfield> had not yet
+         completed as of the time of the snapshot, and thus are invisible.
+       </entry>
+      </row>
+
+      <row>
+       <entry><structfield>xip_list</structfield></entry>
+       <entry>
+        Transactions in progress at the time of the snapshot.  A transaction
+        ID that is <literal>xmin &lt;= <replaceable>X</replaceable> &lt;
+        xmax</literal> and not in this list was already completed at the time
+        of the snapshot, and thus is either visible or dead according to its
+        commit status.  This list does not include the transaction IDs of
+        subtransactions (subxids).
+       </entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    In releases of <productname>PostgreSQL</productname> before 13 there was
+    no <type>xid8</type> type, so variants of these functions were provided
+    that used <type>bigint</type> to represent a 64-bit XID, with a
+    correspondingly distinct snapshot data type <type>txid_snapshot</type>.
+    These older functions have <literal>txid</literal> in their names.  They
+    are still supported for backward compatibility, but may be removed from a
+    future release. See <xref linkend="functions-txid-snapshot"/>.
+   </para>
+
+   <table id="functions-txid-snapshot">
+    <title>Deprecated Transaction ID and Snapshot Information Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>txid_current</primary>
+        </indexterm>
+        <function>txid_current</function> ()
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        See <function>pg_current_xact_id()</function>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>txid_current_if_assigned</primary>
+        </indexterm>
+        <function>txid_current_if_assigned</function> ()
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        See <function>pg_current_xact_id_if_assigned()</function>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>txid_current_snapshot</primary>
+        </indexterm>
+        <function>txid_current_snapshot</function> ()
+        <returnvalue>txid_snapshot</returnvalue>
+       </para>
+       <para>
+        See <function>pg_current_snapshot()</function>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>txid_snapshot_xip</primary>
+        </indexterm>
+        <function>txid_snapshot_xip</function> ( <type>txid_snapshot</type> )
+        <returnvalue>setof bigint</returnvalue>
+       </para>
+       <para>
+        See <function>pg_snapshot_xip()</function>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>txid_snapshot_xmax</primary>
+        </indexterm>
+        <function>txid_snapshot_xmax</function> ( <type>txid_snapshot</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        See <function>pg_snapshot_xmax()</function>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>txid_snapshot_xmin</primary>
+        </indexterm>
+        <function>txid_snapshot_xmin</function> ( <type>txid_snapshot</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        See <function>pg_snapshot_xmin()</function>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>txid_visible_in_snapshot</primary>
+        </indexterm>
+        <function>txid_visible_in_snapshot</function> ( <type>bigint</type>, <type>txid_snapshot</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        See <function>pg_visible_in_snapshot()</function>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>txid_status</primary>
+        </indexterm>
+        <function>txid_status</function> ( <type>bigint</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        See <function>pg_xact_status()</function>.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  </sect2>
+
+  <sect2 id="functions-info-commit-timestamp">
+   <title>Committed Transaction Information Functions</title>
+
+   <para>
+    The functions shown in <xref linkend="functions-commit-timestamp"/>
+    provide information about when past transactions were committed.
+    They only provide useful data when the
+    <xref linkend="guc-track-commit-timestamp"/> configuration option is
+    enabled, and only for transactions that were committed after it was
+    enabled.  Commit timestamp information is routinely removed during
+    vacuum.
+   </para>
+
+   <table id="functions-commit-timestamp">
+    <title>Committed Transaction Information Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_xact_commit_timestamp</primary>
+        </indexterm>
+        <function>pg_xact_commit_timestamp</function> ( <type>xid</type> )
+        <returnvalue>timestamp with time zone</returnvalue>
+       </para>
+       <para>
+        Returns the commit timestamp of a transaction.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_xact_commit_timestamp_origin</primary>
+        </indexterm>
+        <function>pg_xact_commit_timestamp_origin</function> ( <type>xid</type> )
+        <returnvalue>record</returnvalue>
+        ( <parameter>timestamp</parameter> <type>timestamp with time zone</type>,
+         <parameter>roident</parameter> <type>oid</type>)
+       </para>
+       <para>
+         Returns the commit timestamp and replication origin of a transaction.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_last_committed_xact</primary>
+        </indexterm>
+        <function>pg_last_committed_xact</function> ()
+        <returnvalue>record</returnvalue>
+        ( <parameter>xid</parameter> <type>xid</type>,
+        <parameter>timestamp</parameter> <type>timestamp with time zone</type>,
+        <parameter>roident</parameter> <type>oid</type> )
+       </para>
+       <para>
+        Returns the transaction ID, commit timestamp and replication origin
+        of the latest committed transaction.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  </sect2>
+
+  <sect2 id="functions-info-controldata">
+   <title>Control Data Functions</title>
+
+   <para>
+    The functions shown in <xref linkend="functions-controldata"/>
+    print information initialized during <command>initdb</command>, such
+    as the catalog version. They also show information about write-ahead
+    logging and checkpoint processing. This information is cluster-wide,
+    not specific to any one database. These functions provide most of the same
+    information, from the same source, as the
+    <xref linkend="app-pgcontroldata"/> application.
+   </para>
+
+   <table id="functions-controldata">
+    <title>Control Data Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_control_checkpoint</primary>
+        </indexterm>
+        <function>pg_control_checkpoint</function> ()
+        <returnvalue>record</returnvalue>
+       </para>
+       <para>
+        Returns information about current checkpoint state, as shown in
+        <xref linkend="functions-pg-control-checkpoint"/>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_control_system</primary>
+        </indexterm>
+        <function>pg_control_system</function> ()
+        <returnvalue>record</returnvalue>
+       </para>
+       <para>
+        Returns information about current control file state, as shown in
+        <xref linkend="functions-pg-control-system"/>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_control_init</primary>
+        </indexterm>
+        <function>pg_control_init</function> ()
+        <returnvalue>record</returnvalue>
+       </para>
+       <para>
+        Returns information about cluster initialization state, as shown in
+        <xref linkend="functions-pg-control-init"/>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_control_recovery</primary>
+        </indexterm>
+        <function>pg_control_recovery</function> ()
+        <returnvalue>record</returnvalue>
+       </para>
+       <para>
+        Returns information about recovery state, as shown in
+        <xref linkend="functions-pg-control-recovery"/>.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <table id="functions-pg-control-checkpoint">
+    <title><function>pg_control_checkpoint</function> Output Columns</title>
+    <tgroup cols="2">
+     <thead>
+      <row>
+       <entry>Column Name</entry>
+       <entry>Data Type</entry>
+      </row>
+     </thead>
+
+     <tbody>
+
+      <row>
+       <entry><structfield>checkpoint_lsn</structfield></entry>
+       <entry><type>pg_lsn</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>redo_lsn</structfield></entry>
+       <entry><type>pg_lsn</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>redo_wal_file</structfield></entry>
+       <entry><type>text</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>timeline_id</structfield></entry>
+       <entry><type>integer</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>prev_timeline_id</structfield></entry>
+       <entry><type>integer</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>full_page_writes</structfield></entry>
+       <entry><type>boolean</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>next_xid</structfield></entry>
+       <entry><type>text</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>next_oid</structfield></entry>
+       <entry><type>oid</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>next_multixact_id</structfield></entry>
+       <entry><type>xid</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>next_multi_offset</structfield></entry>
+       <entry><type>xid</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>oldest_xid</structfield></entry>
+       <entry><type>xid</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>oldest_xid_dbid</structfield></entry>
+       <entry><type>oid</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>oldest_active_xid</structfield></entry>
+       <entry><type>xid</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>oldest_multi_xid</structfield></entry>
+       <entry><type>xid</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>oldest_multi_dbid</structfield></entry>
+       <entry><type>oid</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>oldest_commit_ts_xid</structfield></entry>
+       <entry><type>xid</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>newest_commit_ts_xid</structfield></entry>
+       <entry><type>xid</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>checkpoint_time</structfield></entry>
+       <entry><type>timestamp with time zone</type></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
+   <table id="functions-pg-control-system">
+    <title><function>pg_control_system</function> Output Columns</title>
+    <tgroup cols="2">
+     <thead>
+      <row>
+       <entry>Column Name</entry>
+       <entry>Data Type</entry>
+      </row>
+     </thead>
+
+     <tbody>
+
+      <row>
+       <entry><structfield>pg_control_version</structfield></entry>
+       <entry><type>integer</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>catalog_version_no</structfield></entry>
+       <entry><type>integer</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>system_identifier</structfield></entry>
+       <entry><type>bigint</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>pg_control_last_modified</structfield></entry>
+       <entry><type>timestamp with time zone</type></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
+   <table id="functions-pg-control-init">
+    <title><function>pg_control_init</function> Output Columns</title>
+    <tgroup cols="2">
+     <thead>
+      <row>
+       <entry>Column Name</entry>
+       <entry>Data Type</entry>
+      </row>
+     </thead>
+
+     <tbody>
+
+      <row>
+       <entry><structfield>max_data_alignment</structfield></entry>
+       <entry><type>integer</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>database_block_size</structfield></entry>
+       <entry><type>integer</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>blocks_per_segment</structfield></entry>
+       <entry><type>integer</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>wal_block_size</structfield></entry>
+       <entry><type>integer</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>bytes_per_wal_segment</structfield></entry>
+       <entry><type>integer</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>max_identifier_length</structfield></entry>
+       <entry><type>integer</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>max_index_columns</structfield></entry>
+       <entry><type>integer</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>max_toast_chunk_size</structfield></entry>
+       <entry><type>integer</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>large_object_chunk_size</structfield></entry>
+       <entry><type>integer</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>float8_pass_by_value</structfield></entry>
+       <entry><type>boolean</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>data_page_checksum_version</structfield></entry>
+       <entry><type>integer</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>default_char_signedness</structfield></entry>
+       <entry><type>boolean</type></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
+   <table id="functions-pg-control-recovery">
+    <title><function>pg_control_recovery</function> Output Columns</title>
+    <tgroup cols="2">
+     <thead>
+      <row>
+       <entry>Column Name</entry>
+       <entry>Data Type</entry>
+      </row>
+     </thead>
+
+     <tbody>
+
+      <row>
+       <entry><structfield>min_recovery_end_lsn</structfield></entry>
+       <entry><type>pg_lsn</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>min_recovery_end_timeline</structfield></entry>
+       <entry><type>integer</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>backup_start_lsn</structfield></entry>
+       <entry><type>pg_lsn</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>backup_end_lsn</structfield></entry>
+       <entry><type>pg_lsn</type></entry>
+      </row>
+
+      <row>
+       <entry><structfield>end_of_backup_record_required</structfield></entry>
+       <entry><type>boolean</type></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
+  </sect2>
+
+  <sect2 id="functions-info-version">
+   <title>Version Information Functions</title>
+
+   <para>
+    The functions shown in <xref linkend="functions-version"/>
+    print version information.
+   </para>
+
+   <table id="functions-version">
+    <title>Version Information Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>version</primary>
+        </indexterm>
+        <function>version</function> ()
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns a string describing the <productname>PostgreSQL</productname>
+        server's version.  You can also get this information from
+        <xref linkend="guc-server-version"/>, or for a machine-readable
+        version use <xref linkend="guc-server-version-num"/>.  Software
+        developers should use <varname>server_version_num</varname> (available
+        since 8.2) or <xref linkend="libpq-PQserverVersion"/> instead of
+        parsing the text version.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>unicode_version</primary>
+        </indexterm>
+        <function>unicode_version</function> ()
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns a string representing the version of Unicode used by
+        <productname>PostgreSQL</productname>.
+       </para></entry>
+      </row>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>icu_unicode_version</primary>
+        </indexterm>
+        <function>icu_unicode_version</function> ()
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns a string representing the version of Unicode used by ICU, if
+        the server was built with ICU support; otherwise returns
+        <literal>NULL</literal> </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  </sect2>
+
+  <sect2 id="functions-info-wal-summary">
+   <title>WAL Summarization Information Functions</title>
+
+   <para>
+    The functions shown in <xref linkend="functions-wal-summary"/>
+    print information about the status of WAL summarization.
+    See <xref linkend="guc-summarize-wal" />.
+   </para>
+
+   <table id="functions-wal-summary">
+    <title>WAL Summarization Information Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_available_wal_summaries</primary>
+        </indexterm>
+        <function>pg_available_wal_summaries</function> ()
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>tli</parameter> <type>bigint</type>,
+        <parameter>start_lsn</parameter> <type>pg_lsn</type>,
+        <parameter>end_lsn</parameter> <type>pg_lsn</type> )
+       </para>
+       <para>
+        Returns information about the WAL summary files present in the
+        data directory, under <literal>pg_wal/summaries</literal>.
+        One row will be returned per WAL summary file. Each file summarizes
+        WAL on the indicated TLI within the indicated LSN range. This function
+        might be useful to determine whether enough WAL summaries are present
+        on the server to take an incremental backup based on some prior
+        backup whose start LSN is known.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_wal_summary_contents</primary>
+        </indexterm>
+        <function>pg_wal_summary_contents</function> ( <parameter>tli</parameter> <type>bigint</type>, <parameter>start_lsn</parameter> <type>pg_lsn</type>, <parameter>end_lsn</parameter> <type>pg_lsn</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>relfilenode</parameter> <type>oid</type>,
+        <parameter>reltablespace</parameter> <type>oid</type>,
+        <parameter>reldatabase</parameter> <type>oid</type>,
+        <parameter>relforknumber</parameter> <type>smallint</type>,
+        <parameter>relblocknumber</parameter> <type>bigint</type>,
+        <parameter>is_limit_block</parameter> <type>boolean</type> )
+       </para>
+       <para>
+        Returns one information about the contents of a single WAL summary file
+        identified by TLI and starting and ending LSNs. Each row with
+        <literal>is_limit_block</literal> false indicates that the block
+        identified by the remaining output columns was modified by at least
+        one WAL record within the range of records summarized by this file.
+        Each row with <literal>is_limit_block</literal> true indicates either
+        that (a) the relation fork was truncated to the length given by
+        <literal>relblocknumber</literal> within the relevant range of WAL
+        records or (b) that the relation fork was created or dropped within
+        the relevant range of WAL records; in such cases,
+        <literal>relblocknumber</literal> will be zero.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_get_wal_summarizer_state</primary>
+        </indexterm>
+        <function>pg_get_wal_summarizer_state</function> ()
+        <returnvalue>record</returnvalue>
+        ( <parameter>summarized_tli</parameter> <type>bigint</type>,
+        <parameter>summarized_lsn</parameter> <type>pg_lsn</type>,
+        <parameter>pending_lsn</parameter> <type>pg_lsn</type>,
+        <parameter>summarizer_pid</parameter> <type>int</type> )
+       </para>
+       <para>
+        Returns information about the progress of the WAL summarizer. If the
+        WAL summarizer has never run since the instance was started, then
+        <literal>summarized_tli</literal> and <literal>summarized_lsn</literal>
+        will be <literal>0</literal> and <literal>0/00000000</literal> respectively;
+        otherwise, they will be the TLI and ending LSN of the last WAL summary
+        file written to disk. If the WAL summarizer is currently running,
+        <literal>pending_lsn</literal> will be the ending LSN of the last
+        record that it has consumed, which must always be greater than or
+        equal to <literal>summarized_lsn</literal>; if the WAL summarizer is
+        not running, it will be equal to <literal>summarized_lsn</literal>.
+        <literal>summarizer_pid</literal> is the PID of the WAL summarizer
+        process, if it is running, and otherwise NULL.
+       </para>
+       <para>
+        As a special exception, the WAL summarizer will refuse to generate
+        WAL summary files if run on WAL generated under
+        <literal>wal_level=minimal</literal>, since such summaries would be
+        unsafe to use as the basis for an incremental backup. In this case,
+        the fields above will continue to advance as if summaries were being
+        generated, but nothing will be written to disk. Once the summarizer
+        reaches WAL generated while <literal>wal_level</literal> was set
+        to <literal>replica</literal> or higher, it will resume writing
+        summaries to disk.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  </sect2>
+
+  </sect1>
diff --git a/doc/src/sgml/func/func-json.sgml b/doc/src/sgml/func/func-json.sgml
new file mode 100644
index 0000000000000..91f98a345d445
--- /dev/null
+++ b/doc/src/sgml/func/func-json.sgml
@@ -0,0 +1,3945 @@
+ <sect1 id="functions-json">
+  <title>JSON Functions and Operators</title>
+
+  <indexterm zone="functions-json">
+   <primary>JSON</primary>
+   <secondary>functions and operators</secondary>
+  </indexterm>
+   <indexterm zone="functions-json">
+    <primary>SQL/JSON</primary>
+    <secondary>functions and expressions</secondary>
+   </indexterm>
+
+  <para>
+   This section describes:
+
+   <itemizedlist>
+    <listitem>
+     <para>
+      functions and operators for processing and creating JSON data
+     </para>
+    </listitem>
+    <listitem>
+     <para>
+      the SQL/JSON path language
+     </para>
+    </listitem>
+    <listitem>
+     <para>
+      the SQL/JSON query functions
+     </para>
+    </listitem>
+   </itemizedlist>
+  </para>
+
+  <para>
+   To provide native support for JSON data types within the SQL environment,
+   <productname>PostgreSQL</productname> implements the
+   <firstterm>SQL/JSON data model</firstterm>.
+   This model comprises sequences of items. Each item can hold SQL scalar
+   values, with an additional SQL/JSON null value, and composite data structures
+   that use JSON arrays and objects. The model is a formalization of the implied
+   data model in the JSON specification
+   <ulink url="https://datatracker.ietf.org/doc/html/rfc7159">RFC 7159</ulink>.
+  </para>
+
+  <para>
+   SQL/JSON allows you to handle JSON data alongside regular SQL data,
+   with transaction support, including:
+
+  <itemizedlist>
+   <listitem>
+    <para>
+     Uploading JSON data into the database and storing it in
+     regular SQL columns as character or binary strings.
+    </para>
+   </listitem>
+   <listitem>
+    <para>
+     Generating JSON objects and arrays from relational data.
+    </para>
+   </listitem>
+   <listitem>
+    <para>
+     Querying JSON data using SQL/JSON query functions and
+     SQL/JSON path language expressions.
+    </para>
+   </listitem>
+  </itemizedlist>
+  </para>
+
+  <para>
+   To learn more about the SQL/JSON standard, see
+   <xref linkend="sqltr-19075-6"/>. For details on JSON types
+   supported in <productname>PostgreSQL</productname>,
+   see <xref linkend="datatype-json"/>.
+  </para>
+
+  <sect2 id="functions-json-processing">
+   <title>Processing and Creating JSON Data</title>
+
+  <para>
+   <xref linkend="functions-json-op-table"/> shows the operators that
+   are available for use with JSON data types (see <xref
+   linkend="datatype-json"/>).
+   In addition, the usual comparison operators shown in <xref
+   linkend="functions-comparison-op-table"/> are available for
+   <type>jsonb</type>, though not for <type>json</type>.  The comparison
+   operators follow the ordering rules for B-tree operations outlined in
+   <xref linkend="json-indexing"/>.
+   See also <xref linkend="functions-aggregate"/> for the aggregate
+   function <function>json_agg</function> which aggregates record
+   values as JSON, the aggregate function
+   <function>json_object_agg</function> which aggregates pairs of values
+   into a JSON object, and their <type>jsonb</type> equivalents,
+   <function>jsonb_agg</function> and <function>jsonb_object_agg</function>.
+  </para>
+
+  <table id="functions-json-op-table">
+    <title><type>json</type> and <type>jsonb</type> Operators</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Operator
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>json</type> <literal>-&gt;</literal> <type>integer</type>
+        <returnvalue>json</returnvalue>
+       </para>
+       <para role="func_signature">
+        <type>jsonb</type> <literal>-&gt;</literal> <type>integer</type>
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Extracts <parameter>n</parameter>'th element of JSON array
+        (array elements are indexed from zero, but negative integers count
+        from the end).
+       </para>
+       <para>
+        <literal>'[{"a":"foo"},{"b":"bar"},{"c":"baz"}]'::json -&gt; 2</literal>
+        <returnvalue>{"c":"baz"}</returnvalue>
+       </para>
+       <para>
+        <literal>'[{"a":"foo"},{"b":"bar"},{"c":"baz"}]'::json -&gt; -3</literal>
+        <returnvalue>{"a":"foo"}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>json</type> <literal>-&gt;</literal> <type>text</type>
+        <returnvalue>json</returnvalue>
+       </para>
+       <para role="func_signature">
+        <type>jsonb</type> <literal>-&gt;</literal> <type>text</type>
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Extracts JSON object field with the given key.
+       </para>
+       <para>
+        <literal>'{"a": {"b":"foo"}}'::json -&gt; 'a'</literal>
+        <returnvalue>{"b":"foo"}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>json</type> <literal>-&gt;&gt;</literal> <type>integer</type>
+        <returnvalue>text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <type>jsonb</type> <literal>-&gt;&gt;</literal> <type>integer</type>
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Extracts <parameter>n</parameter>'th element of JSON array,
+        as <type>text</type>.
+       </para>
+       <para>
+        <literal>'[1,2,3]'::json -&gt;&gt; 2</literal>
+        <returnvalue>3</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>json</type> <literal>-&gt;&gt;</literal> <type>text</type>
+        <returnvalue>text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <type>jsonb</type> <literal>-&gt;&gt;</literal> <type>text</type>
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Extracts JSON object field with the given key, as <type>text</type>.
+       </para>
+       <para>
+        <literal>'{"a":1,"b":2}'::json -&gt;&gt; 'b'</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>json</type> <literal>#&gt;</literal> <type>text[]</type>
+        <returnvalue>json</returnvalue>
+       </para>
+       <para role="func_signature">
+        <type>jsonb</type> <literal>#&gt;</literal> <type>text[]</type>
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Extracts JSON sub-object at the specified path, where path elements
+        can be either field keys or array indexes.
+       </para>
+       <para>
+        <literal>'{"a": {"b": ["foo","bar"]}}'::json #&gt; '{a,b,1}'</literal>
+        <returnvalue>"bar"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>json</type> <literal>#&gt;&gt;</literal> <type>text[]</type>
+        <returnvalue>text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <type>jsonb</type> <literal>#&gt;&gt;</literal> <type>text[]</type>
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Extracts JSON sub-object at the specified path as <type>text</type>.
+       </para>
+       <para>
+        <literal>'{"a": {"b": ["foo","bar"]}}'::json #&gt;&gt; '{a,b,1}'</literal>
+        <returnvalue>bar</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <note>
+   <para>
+    The field/element/path extraction operators return NULL, rather than
+    failing, if the JSON input does not have the right structure to match
+    the request; for example if no such key or array element exists.
+   </para>
+  </note>
+
+  <para>
+   Some further operators exist only for <type>jsonb</type>, as shown
+   in <xref linkend="functions-jsonb-op-table"/>.
+   <xref linkend="json-indexing"/>
+   describes how these operators can be used to effectively search indexed
+   <type>jsonb</type> data.
+  </para>
+
+  <table id="functions-jsonb-op-table">
+    <title>Additional <type>jsonb</type> Operators</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Operator
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>jsonb</type> <literal>@&gt;</literal> <type>jsonb</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the first JSON value contain the second?
+        (See <xref linkend="json-containment"/> for details about containment.)
+       </para>
+       <para>
+        <literal>'{"a":1, "b":2}'::jsonb &#64;&gt; '{"b":2}'::jsonb</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>jsonb</type> <literal>&lt;@</literal> <type>jsonb</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the first JSON value contained in the second?
+       </para>
+       <para>
+        <literal>'{"b":2}'::jsonb &lt;@ '{"a":1, "b":2}'::jsonb</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>jsonb</type> <literal>?</literal> <type>text</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the text string exist as a top-level key or array element within
+        the JSON value?
+       </para>
+       <para>
+        <literal>'{"a":1, "b":2}'::jsonb ? 'b'</literal>
+        <returnvalue>t</returnvalue>
+       </para>
+       <para>
+        <literal>'["a", "b", "c"]'::jsonb ? 'b'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>jsonb</type> <literal>?|</literal> <type>text[]</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Do any of the strings in the text array exist as top-level keys or
+        array elements?
+       </para>
+       <para>
+        <literal>'{"a":1, "b":2, "c":3}'::jsonb ?| array['b', 'd']</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>jsonb</type> <literal>?&amp;</literal> <type>text[]</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Do all of the strings in the text array exist as top-level keys or
+        array elements?
+       </para>
+       <para>
+        <literal>'["a", "b", "c"]'::jsonb ?&amp; array['a', 'b']</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>jsonb</type> <literal>||</literal> <type>jsonb</type>
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Concatenates two <type>jsonb</type> values.
+        Concatenating two arrays generates an array containing all the
+        elements of each input.  Concatenating two objects generates an
+        object containing the union of their
+        keys, taking the second object's value when there are duplicate keys.
+        All other cases are treated by converting a non-array input into a
+        single-element array, and then proceeding as for two arrays.
+        Does not operate recursively: only the top-level array or object
+        structure is merged.
+       </para>
+       <para>
+        <literal>'["a", "b"]'::jsonb || '["a", "d"]'::jsonb</literal>
+        <returnvalue>["a", "b", "a", "d"]</returnvalue>
+       </para>
+       <para>
+        <literal>'{"a": "b"}'::jsonb || '{"c": "d"}'::jsonb</literal>
+        <returnvalue>{"a": "b", "c": "d"}</returnvalue>
+       </para>
+       <para>
+        <literal>'[1, 2]'::jsonb || '3'::jsonb</literal>
+        <returnvalue>[1, 2, 3]</returnvalue>
+       </para>
+       <para>
+        <literal>'{"a": "b"}'::jsonb || '42'::jsonb</literal>
+        <returnvalue>[{"a": "b"}, 42]</returnvalue>
+       </para>
+       <para>
+        To append an array to another array as a single entry, wrap it
+        in an additional layer of array, for example:
+       </para>
+       <para>
+        <literal>'[1, 2]'::jsonb || jsonb_build_array('[3, 4]'::jsonb)</literal>
+        <returnvalue>[1, 2, [3, 4]]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>jsonb</type> <literal>-</literal> <type>text</type>
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Deletes a key (and its value) from a JSON object, or matching string
+        value(s) from a JSON array.
+       </para>
+       <para>
+        <literal>'{"a": "b", "c": "d"}'::jsonb - 'a'</literal>
+        <returnvalue>{"c": "d"}</returnvalue>
+       </para>
+       <para>
+        <literal>'["a", "b", "c", "b"]'::jsonb - 'b'</literal>
+        <returnvalue>["a", "c"]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>jsonb</type> <literal>-</literal> <type>text[]</type>
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Deletes all matching keys or array elements from the left operand.
+       </para>
+       <para>
+        <literal>'{"a": "b", "c": "d"}'::jsonb - '{a,c}'::text[]</literal>
+        <returnvalue>{}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>jsonb</type> <literal>-</literal> <type>integer</type>
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Deletes the array element with specified index (negative
+        integers count from the end).  Throws an error if JSON value
+        is not an array.
+       </para>
+       <para>
+        <literal>'["a", "b"]'::jsonb - 1 </literal>
+        <returnvalue>["a"]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>jsonb</type> <literal>#-</literal> <type>text[]</type>
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Deletes the field or array element at the specified path, where path
+        elements can be either field keys or array indexes.
+       </para>
+       <para>
+        <literal>'["a", {"b":1}]'::jsonb #- '{1,b}'</literal>
+        <returnvalue>["a", {}]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>jsonb</type> <literal>@?</literal> <type>jsonpath</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does JSON path return any item for the specified JSON value?
+        (This is useful only with SQL-standard JSON path expressions, not
+        <link linkend="functions-sqljson-check-expressions">predicate check
+        expressions</link>, since those always return a value.)
+       </para>
+       <para>
+        <literal>'{"a":[1,2,3,4,5]}'::jsonb @? '$.a[*] ? (@ > 2)'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>jsonb</type> <literal>@@</literal> <type>jsonpath</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Returns the result of a JSON path predicate check for the
+        specified JSON value.
+        (This is useful only
+        with <link linkend="functions-sqljson-check-expressions">predicate
+        check expressions</link>, not SQL-standard JSON path expressions,
+        since it will return <literal>NULL</literal> if the path result is
+        not a single boolean value.)
+       </para>
+       <para>
+        <literal>'{"a":[1,2,3,4,5]}'::jsonb @@ '$.a[*] > 2'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <note>
+   <para>
+    The <type>jsonpath</type> operators <literal>@?</literal>
+    and <literal>@@</literal> suppress the following errors: missing object
+    field or array element, unexpected JSON item type, datetime and numeric
+    errors.  The <type>jsonpath</type>-related functions described below can
+    also be told to suppress these types of errors.  This behavior might be
+    helpful when searching JSON document collections of varying structure.
+   </para>
+  </note>
+
+  <para>
+   <xref linkend="functions-json-creation-table"/> shows the functions that are
+   available for constructing <type>json</type> and <type>jsonb</type> values.
+   Some functions in this table have a <literal>RETURNING</literal> clause,
+   which specifies the data type returned.  It must be one of <type>json</type>,
+   <type>jsonb</type>, <type>bytea</type>, a character string type (<type>text</type>,
+   <type>char</type>, or <type>varchar</type>), or a type
+   that can be cast to <type>json</type>.
+   By default, the <type>json</type> type is returned.
+  </para>
+
+  <table id="functions-json-creation-table">
+    <title>JSON Creation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_json</primary>
+        </indexterm>
+        <function>to_json</function> ( <type>anyelement</type> )
+        <returnvalue>json</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>to_jsonb</primary>
+        </indexterm>
+        <function>to_jsonb</function> ( <type>anyelement</type> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Converts any SQL value to <type>json</type> or <type>jsonb</type>.
+        Arrays and composites are converted recursively to arrays and
+        objects (multidimensional arrays become arrays of arrays in JSON).
+        Otherwise, if there is a cast from the SQL data type
+        to <type>json</type>, the cast function will be used to perform the
+        conversion;<footnote>
+         <para>
+          For example, the <xref linkend="hstore"/> extension has a cast
+          from <type>hstore</type> to <type>json</type>, so that
+          <type>hstore</type> values converted via the JSON creation functions
+          will be represented as JSON objects, not as primitive string values.
+         </para>
+        </footnote>
+        otherwise, a scalar JSON value is produced.  For any scalar other than
+        a number, a Boolean, or a null value, the text representation will be
+        used, with escaping as necessary to make it a valid JSON string value.
+       </para>
+       <para>
+        <literal>to_json('Fred said "Hi."'::text)</literal>
+        <returnvalue>"Fred said \"Hi.\""</returnvalue>
+       </para>
+       <para>
+        <literal>to_jsonb(row(42, 'Fred said "Hi."'::text))</literal>
+        <returnvalue>{"f1": 42, "f2": "Fred said \"Hi.\""}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_to_json</primary>
+        </indexterm>
+        <function>array_to_json</function> ( <type>anyarray</type> <optional>, <type>boolean</type> </optional> )
+        <returnvalue>json</returnvalue>
+       </para>
+       <para>
+        Converts an SQL array to a JSON array.  The behavior is the same
+        as <function>to_json</function> except that line feeds will be added
+        between top-level array elements if the optional boolean parameter is
+        true.
+       </para>
+       <para>
+        <literal>array_to_json('{{1,5},{99,100}}'::int[])</literal>
+        <returnvalue>[[1,5],[99,100]]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <!--
+           Note that this is barely legible in the output; it looks like a
+           salad of braces and brackets.  It would be better to split it out
+           in multiple lines, but that's surprisingly hard to do in a way that
+           matches in HTML and PDF output.  Other standard SQL/JSON functions
+           have the same problem.
+         -->
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm><primary>json_array</primary></indexterm>
+         <function>json_array</function> (
+         <optional> { <replaceable>value_expression</replaceable> <optional> <literal>FORMAT JSON</literal> </optional> } <optional>, ...</optional> </optional>
+         <optional> { <literal>NULL</literal> | <literal>ABSENT</literal> } <literal>ON NULL</literal> </optional>
+         <optional> <literal>RETURNING</literal> <replaceable>data_type</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional> </optional>)
+        </para>
+        <para role="func_signature">
+         <function>json_array</function> (
+         <optional> <replaceable>query_expression</replaceable> </optional>
+         <optional> <literal>RETURNING</literal> <replaceable>data_type</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional> </optional>)
+        </para>
+        <para>
+         Constructs a JSON array from either a series of
+         <replaceable>value_expression</replaceable> parameters or from the results
+         of <replaceable>query_expression</replaceable>,
+         which must be a SELECT query returning a single column. If
+         <literal>ABSENT ON NULL</literal> is specified, NULL values are ignored.
+         This is always the case if a
+         <replaceable>query_expression</replaceable> is used.
+        </para>
+        <para>
+         <literal>json_array(1,true,json '{"a":null}')</literal>
+         <returnvalue>[1, true, {"a":null}]</returnvalue>
+        </para>
+        <para>
+         <literal>json_array(SELECT * FROM (VALUES(1),(2)) t)</literal>
+         <returnvalue>[1, 2]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>row_to_json</primary>
+        </indexterm>
+        <function>row_to_json</function> ( <type>record</type> <optional>, <type>boolean</type> </optional> )
+        <returnvalue>json</returnvalue>
+       </para>
+       <para>
+        Converts an SQL composite value to a JSON object.  The behavior is the
+        same as <function>to_json</function> except that line feeds will be
+        added between top-level elements if the optional boolean parameter is
+        true.
+       </para>
+       <para>
+        <literal>row_to_json(row(1,'foo'))</literal>
+        <returnvalue>{"f1":1,"f2":"foo"}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_build_array</primary>
+        </indexterm>
+        <function>json_build_array</function> ( <literal>VARIADIC</literal> <type>"any"</type> )
+        <returnvalue>json</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_build_array</primary>
+        </indexterm>
+        <function>jsonb_build_array</function> ( <literal>VARIADIC</literal> <type>"any"</type> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Builds a possibly-heterogeneously-typed JSON array out of a variadic
+        argument list.  Each argument is converted as
+        per <function>to_json</function> or <function>to_jsonb</function>.
+       </para>
+       <para>
+        <literal>json_build_array(1, 2, 'foo', 4, 5)</literal>
+        <returnvalue>[1, 2, "foo", 4, 5]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_build_object</primary>
+        </indexterm>
+        <function>json_build_object</function> ( <literal>VARIADIC</literal> <type>"any"</type> )
+        <returnvalue>json</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_build_object</primary>
+        </indexterm>
+        <function>jsonb_build_object</function> ( <literal>VARIADIC</literal> <type>"any"</type> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Builds a JSON object out of a variadic argument list.  By convention,
+        the argument list consists of alternating keys and values.  Key
+        arguments are coerced to text; value arguments are converted as
+        per <function>to_json</function> or <function>to_jsonb</function>.
+       </para>
+       <para>
+        <literal>json_build_object('foo', 1, 2, row(3,'bar'))</literal>
+        <returnvalue>{"foo" : 1, "2" : {"f1":3,"f2":"bar"}}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+         <indexterm><primary>json_object</primary></indexterm>
+         <function>json_object</function> (
+         <optional> { <replaceable>key_expression</replaceable> { <literal>VALUE</literal> | ':' }
+          <replaceable>value_expression</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional> }<optional>, ...</optional> </optional>
+         <optional> { <literal>NULL</literal> | <literal>ABSENT</literal> } <literal>ON NULL</literal> </optional>
+         <optional> { <literal>WITH</literal> | <literal>WITHOUT</literal> } <literal>UNIQUE</literal> <optional> <literal>KEYS</literal> </optional> </optional>
+         <optional> <literal>RETURNING</literal> <replaceable>data_type</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional> </optional>)
+        </para>
+        <para>
+         Constructs a JSON object of all the key/value pairs given,
+         or an empty object if none are given.
+         <replaceable>key_expression</replaceable> is a scalar expression
+         defining the <acronym>JSON</acronym> key, which is
+         converted to the <type>text</type> type.
+         It cannot be <literal>NULL</literal> nor can it
+         belong to a type that has a cast to the <type>json</type> type.
+         If <literal>WITH UNIQUE KEYS</literal> is specified, there must not
+         be any duplicate <replaceable>key_expression</replaceable>.
+         Any pair for which the <replaceable>value_expression</replaceable>
+         evaluates to <literal>NULL</literal> is omitted from the output
+         if <literal>ABSENT ON NULL</literal> is specified;
+         if <literal>NULL ON NULL</literal> is specified or the clause
+         omitted, the key is included with value <literal>NULL</literal>.
+        </para>
+        <para>
+         <literal>json_object('code' VALUE 'P123', 'title': 'Jaws')</literal>
+         <returnvalue>{"code" : "P123", "title" : "Jaws"}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_object</primary>
+        </indexterm>
+        <function>json_object</function> ( <type>text[]</type> )
+        <returnvalue>json</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_object</primary>
+        </indexterm>
+        <function>jsonb_object</function> ( <type>text[]</type> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Builds a JSON object out of a text array.  The array must have either
+        exactly one dimension with an even number of members, in which case
+        they are taken as alternating key/value pairs, or two dimensions
+        such that each inner array has exactly two elements, which
+        are taken as a key/value pair.  All values are converted to JSON
+        strings.
+       </para>
+       <para>
+        <literal>json_object('{a, 1, b, "def", c, 3.5}')</literal>
+        <returnvalue>{"a" : "1", "b" : "def", "c" : "3.5"}</returnvalue>
+       </para>
+        <para><literal>json_object('{{a, 1}, {b, "def"}, {c, 3.5}}')</literal>
+        <returnvalue>{"a" : "1", "b" : "def", "c" : "3.5"}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>json_object</function> ( <parameter>keys</parameter> <type>text[]</type>, <parameter>values</parameter> <type>text[]</type> )
+        <returnvalue>json</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>jsonb_object</function> ( <parameter>keys</parameter> <type>text[]</type>, <parameter>values</parameter> <type>text[]</type> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        This form of <function>json_object</function> takes keys and values
+        pairwise from separate text arrays.  Otherwise it is identical to
+        the one-argument form.
+       </para>
+       <para>
+        <literal>json_object('{a,b}', '{1,2}')</literal>
+        <returnvalue>{"a": "1", "b": "2"}</returnvalue>
+       </para></entry>
+      </row>
+      <row>
+       <entry role="func_table_entry">
+        <para role="func_signature">
+         <indexterm><primary>json constructor</primary></indexterm>
+         <function>json</function> (
+         <replaceable>expression</replaceable>
+         <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional></optional>
+         <optional> { <literal>WITH</literal> | <literal>WITHOUT</literal> } <literal>UNIQUE</literal> <optional> <literal>KEYS</literal> </optional></optional> )
+         <returnvalue>json</returnvalue>
+        </para>
+        <para>
+         Converts a given expression specified as <type>text</type> or
+         <type>bytea</type> string (in UTF8 encoding) into a JSON
+         value.  If <replaceable>expression</replaceable> is NULL, an
+         <acronym>SQL</acronym> null value is returned.
+         If <literal>WITH UNIQUE</literal> is specified, the
+         <replaceable>expression</replaceable> must not contain any duplicate
+         object keys.
+        </para>
+        <para>
+         <literal>json('{"a":123, "b":[true,"foo"], "a":"bar"}')</literal>
+         <returnvalue>{"a":123, "b":[true,"foo"], "a":"bar"}</returnvalue>
+        </para>
+       </entry>
+      </row>
+      <row>
+       <entry role="func_table_entry">
+        <para role="func_signature">
+        <indexterm><primary>json_scalar</primary></indexterm>
+        <function>json_scalar</function> ( <replaceable>expression</replaceable> )
+       </para>
+       <para>
+        Converts a given SQL scalar value into a JSON scalar value.
+        If the input is NULL, an <acronym>SQL</acronym> null is returned. If
+        the input is number or a boolean value, a corresponding JSON number
+        or boolean value is returned. For any other value, a JSON string is
+        returned.
+       </para>
+       <para>
+        <literal>json_scalar(123.45)</literal>
+        <returnvalue>123.45</returnvalue>
+       </para>
+       <para>
+        <literal>json_scalar(CURRENT_TIMESTAMP)</literal>
+        <returnvalue>"2022-05-10T10:51:04.62128-04:00"</returnvalue>
+      </para></entry>
+     </row>
+     <row>
+      <entry role="func_table_entry">
+       <para role="func_signature">
+        <function>json_serialize</function> (
+        <replaceable>expression</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional>
+        <optional> <literal>RETURNING</literal> <replaceable>data_type</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional> </optional> )
+       </para>
+       <para>
+        Converts an SQL/JSON expression into a character or binary string. The
+        <replaceable>expression</replaceable> can be of any JSON type, any
+        character string type, or <type>bytea</type> in UTF8 encoding.
+        The returned type used in <literal> RETURNING</literal> can be any
+        character string type or <type>bytea</type>. The default is
+        <type>text</type>.
+       </para>
+       <para>
+        <literal>json_serialize('{ "a" : 1 } ' RETURNING bytea)</literal>
+        <returnvalue>\x7b20226122203a2031207d20</returnvalue>
+      </para></entry>
+     </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <para>
+   <xref linkend="functions-sqljson-misc" /> details SQL/JSON
+   facilities for testing JSON.
+  </para>
+
+  <table id="functions-sqljson-misc">
+   <title>SQL/JSON Testing Functions</title>
+   <tgroup cols="1">
+    <thead>
+     <row>
+      <entry role="func_table_entry"><para role="func_signature">
+        Function signature
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+      </para></entry>
+     </row>
+    </thead>
+    <tbody>
+     <row>
+      <entry role="func_table_entry"><para role="func_signature">
+        <indexterm><primary>IS JSON</primary></indexterm>
+        <replaceable>expression</replaceable> <literal>IS</literal> <optional> <literal>NOT</literal> </optional> <literal>JSON</literal>
+        <optional> { <literal>VALUE</literal> | <literal>SCALAR</literal> | <literal>ARRAY</literal> | <literal>OBJECT</literal> } </optional>
+        <optional> { <literal>WITH</literal> | <literal>WITHOUT</literal> } <literal>UNIQUE</literal> <optional> <literal>KEYS</literal> </optional> </optional>
+       </para>
+       <para>
+        This predicate tests whether <replaceable>expression</replaceable> can be
+        parsed as JSON, possibly of a specified type.
+        If <literal>SCALAR</literal> or <literal>ARRAY</literal> or
+        <literal>OBJECT</literal> is specified, the
+        test is whether or not the JSON is of that particular type. If
+        <literal>WITH UNIQUE KEYS</literal> is specified, then any object in the
+        <replaceable>expression</replaceable> is also tested to see if it
+        has duplicate keys.
+       </para>
+       <para>
+<programlisting>
+SELECT js,
+  js IS JSON "json?",
+  js IS JSON SCALAR "scalar?",
+  js IS JSON OBJECT "object?",
+  js IS JSON ARRAY "array?"
+FROM (VALUES
+      ('123'), ('"abc"'), ('{"a": "b"}'), ('[1,2]'),('abc')) foo(js);
+     js     | json? | scalar? | object? | array?
+------------+-------+---------+---------+--------
+ 123        | t     | t       | f       | f
+ "abc"      | t     | t       | f       | f
+ {"a": "b"} | t     | f       | t       | f
+ [1,2]      | t     | f       | f       | t
+ abc        | f     | f       | f       | f
+</programlisting>
+       </para>
+       <para>
+<programlisting>
+SELECT js,
+  js IS JSON OBJECT "object?",
+  js IS JSON ARRAY "array?",
+  js IS JSON ARRAY WITH UNIQUE KEYS "array w. UK?",
+  js IS JSON ARRAY WITHOUT UNIQUE KEYS "array w/o UK?"
+FROM (VALUES ('[{"a":"1"},
+ {"b":"2","b":"3"}]')) foo(js);
+-[ RECORD 1 ]-+--------------------
+js            | [{"a":"1"},        +
+              |  {"b":"2","b":"3"}]
+object?       | f
+array?        | t
+array w. UK?  | f
+array w/o UK? | t
+</programlisting>
+      </para></entry>
+     </row>
+    </tbody>
+   </tgroup>
+  </table>
+
+  <para>
+   <xref linkend="functions-json-processing-table"/> shows the functions that
+   are available for processing <type>json</type> and <type>jsonb</type> values.
+  </para>
+
+  <table id="functions-json-processing-table">
+    <title>JSON Processing Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_array_elements</primary>
+        </indexterm>
+        <function>json_array_elements</function> ( <type>json</type> )
+        <returnvalue>setof json</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_array_elements</primary>
+        </indexterm>
+        <function>jsonb_array_elements</function> ( <type>jsonb</type> )
+        <returnvalue>setof jsonb</returnvalue>
+       </para>
+       <para>
+        Expands the top-level JSON array into a set of JSON values.
+       </para>
+       <para>
+        <literal>select * from json_array_elements('[1,true, [2,false]]')</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+   value
+-----------
+ 1
+ true
+ [2,false]
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_array_elements_text</primary>
+        </indexterm>
+        <function>json_array_elements_text</function> ( <type>json</type> )
+        <returnvalue>setof text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_array_elements_text</primary>
+        </indexterm>
+        <function>jsonb_array_elements_text</function> ( <type>jsonb</type> )
+        <returnvalue>setof text</returnvalue>
+       </para>
+       <para>
+        Expands the top-level JSON array into a set of <type>text</type> values.
+       </para>
+       <para>
+        <literal>select * from json_array_elements_text('["foo", "bar"]')</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+   value
+-----------
+ foo
+ bar
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_array_length</primary>
+        </indexterm>
+        <function>json_array_length</function> ( <type>json</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_array_length</primary>
+        </indexterm>
+        <function>jsonb_array_length</function> ( <type>jsonb</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the number of elements in the top-level JSON array.
+       </para>
+       <para>
+        <literal>json_array_length('[1,2,3,{"f1":1,"f2":[5,6]},4]')</literal>
+        <returnvalue>5</returnvalue>
+       </para>
+       <para>
+        <literal>jsonb_array_length('[]')</literal>
+        <returnvalue>0</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_each</primary>
+        </indexterm>
+        <function>json_each</function> ( <type>json</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>key</parameter> <type>text</type>,
+        <parameter>value</parameter> <type>json</type> )
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_each</primary>
+        </indexterm>
+        <function>jsonb_each</function> ( <type>jsonb</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>key</parameter> <type>text</type>,
+        <parameter>value</parameter> <type>jsonb</type> )
+       </para>
+       <para>
+        Expands the top-level JSON object into a set of key/value pairs.
+       </para>
+       <para>
+        <literal>select * from json_each('{"a":"foo", "b":"bar"}')</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ key | value
+-----+-------
+ a   | "foo"
+ b   | "bar"
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_each_text</primary>
+        </indexterm>
+        <function>json_each_text</function> ( <type>json</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>key</parameter> <type>text</type>,
+        <parameter>value</parameter> <type>text</type> )
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_each_text</primary>
+        </indexterm>
+        <function>jsonb_each_text</function> ( <type>jsonb</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>key</parameter> <type>text</type>,
+        <parameter>value</parameter> <type>text</type> )
+       </para>
+       <para>
+        Expands the top-level JSON object into a set of key/value pairs.
+        The returned <parameter>value</parameter>s will be of
+        type <type>text</type>.
+       </para>
+       <para>
+        <literal>select * from json_each_text('{"a":"foo", "b":"bar"}')</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ key | value
+-----+-------
+ a   | foo
+ b   | bar
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_extract_path</primary>
+        </indexterm>
+        <function>json_extract_path</function> ( <parameter>from_json</parameter> <type>json</type>, <literal>VARIADIC</literal> <parameter>path_elems</parameter> <type>text[]</type> )
+        <returnvalue>json</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_extract_path</primary>
+        </indexterm>
+        <function>jsonb_extract_path</function> ( <parameter>from_json</parameter> <type>jsonb</type>, <literal>VARIADIC</literal> <parameter>path_elems</parameter> <type>text[]</type> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Extracts JSON sub-object at the specified path.
+        (This is functionally equivalent to the <literal>#&gt;</literal>
+        operator, but writing the path out as a variadic list can be more
+        convenient in some cases.)
+       </para>
+       <para>
+        <literal>json_extract_path('{"f2":{"f3":1},"f4":{"f5":99,"f6":"foo"}}', 'f4', 'f6')</literal>
+        <returnvalue>"foo"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_extract_path_text</primary>
+        </indexterm>
+        <function>json_extract_path_text</function> ( <parameter>from_json</parameter> <type>json</type>, <literal>VARIADIC</literal> <parameter>path_elems</parameter> <type>text[]</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_extract_path_text</primary>
+        </indexterm>
+        <function>jsonb_extract_path_text</function> ( <parameter>from_json</parameter> <type>jsonb</type>, <literal>VARIADIC</literal> <parameter>path_elems</parameter> <type>text[]</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Extracts JSON sub-object at the specified path as <type>text</type>.
+        (This is functionally equivalent to the <literal>#&gt;&gt;</literal>
+        operator.)
+       </para>
+       <para>
+        <literal>json_extract_path_text('{"f2":{"f3":1},"f4":{"f5":99,"f6":"foo"}}', 'f4', 'f6')</literal>
+        <returnvalue>foo</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_object_keys</primary>
+        </indexterm>
+        <function>json_object_keys</function> ( <type>json</type> )
+        <returnvalue>setof text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_object_keys</primary>
+        </indexterm>
+        <function>jsonb_object_keys</function> ( <type>jsonb</type> )
+        <returnvalue>setof text</returnvalue>
+       </para>
+       <para>
+        Returns the set of keys in the top-level JSON object.
+       </para>
+       <para>
+        <literal>select * from json_object_keys('{"f1":"abc","f2":{"f3":"a", "f4":"b"}}')</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ json_object_keys
+------------------
+ f1
+ f2
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_populate_record</primary>
+        </indexterm>
+        <function>json_populate_record</function> ( <parameter>base</parameter> <type>anyelement</type>, <parameter>from_json</parameter> <type>json</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_populate_record</primary>
+        </indexterm>
+        <function>jsonb_populate_record</function> ( <parameter>base</parameter> <type>anyelement</type>, <parameter>from_json</parameter> <type>jsonb</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Expands the top-level JSON object to a row having the composite type
+        of the <parameter>base</parameter> argument.  The JSON object
+        is scanned for fields whose names match column names of the output row
+        type, and their values are inserted into those columns of the output.
+        (Fields that do not correspond to any output column name are ignored.)
+        In typical use, the value of <parameter>base</parameter> is just
+        <literal>NULL</literal>, which means that any output columns that do
+        not match any object field will be filled with nulls.  However,
+        if <parameter>base</parameter> isn't <literal>NULL</literal> then
+        the values it contains will be used for unmatched columns.
+       </para>
+       <para>
+        To convert a JSON value to the SQL type of an output column, the
+        following rules are applied in sequence:
+        <itemizedlist spacing="compact">
+         <listitem>
+          <para>
+           A JSON null value is converted to an SQL null in all cases.
+          </para>
+         </listitem>
+         <listitem>
+          <para>
+           If the output column is of type <type>json</type>
+           or <type>jsonb</type>, the JSON value is just reproduced exactly.
+          </para>
+         </listitem>
+         <listitem>
+          <para>
+           If the output column is a composite (row) type, and the JSON value
+           is a JSON object, the fields of the object are converted to columns
+           of the output row type by recursive application of these rules.
+          </para>
+         </listitem>
+         <listitem>
+          <para>
+           Likewise, if the output column is an array type and the JSON value
+           is a JSON array, the elements of the JSON array are converted to
+           elements of the output array by recursive application of these
+           rules.
+          </para>
+         </listitem>
+         <listitem>
+          <para>
+           Otherwise, if the JSON value is a string, the contents of the
+           string are fed to the input conversion function for the column's
+           data type.
+          </para>
+         </listitem>
+         <listitem>
+          <para>
+           Otherwise, the ordinary text representation of the JSON value is
+           fed to the input conversion function for the column's data type.
+          </para>
+         </listitem>
+        </itemizedlist>
+       </para>
+       <para>
+        While the example below uses a constant JSON value, typical use would
+        be to reference a <type>json</type> or <type>jsonb</type> column
+        laterally from another table in the query's <literal>FROM</literal>
+        clause.  Writing <function>json_populate_record</function> in
+        the <literal>FROM</literal> clause is good practice, since all of the
+        extracted columns are available for use without duplicate function
+        calls.
+       </para>
+       <para>
+        <literal>create type subrowtype as (d int, e text);</literal>
+        <literal>create type myrowtype as (a int, b text[], c subrowtype);</literal>
+       </para>
+       <para>
+        <literal>select * from json_populate_record(null::myrowtype,
+         '{"a": 1, "b": ["2", "a b"], "c": {"d": 4, "e": "a  b c"}, "x": "foo"}')</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ a |   b       |      c
+---+-----------+-------------
+ 1 | {2,"a b"} | (4,"a b c")
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>jsonb_populate_record_valid</primary>
+        </indexterm>
+        <function>jsonb_populate_record_valid</function> ( <parameter>base</parameter> <type>anyelement</type>, <parameter>from_json</parameter> <type>json</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Function for testing <function>jsonb_populate_record</function>.  Returns
+        <literal>true</literal> if the input <function>jsonb_populate_record</function>
+        would finish without an error for the given input JSON object; that is, it's
+        valid input, <literal>false</literal> otherwise.
+       </para>
+       <para>
+        <literal>create type jsb_char2 as (a char(2));</literal>
+       </para>
+       <para>
+        <literal>select jsonb_populate_record_valid(NULL::jsb_char2, '{"a": "aaa"}');</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ jsonb_populate_record_valid
+-----------------------------
+ f
+(1 row)
+</programlisting>
+
+        <literal>select * from jsonb_populate_record(NULL::jsb_char2, '{"a": "aaa"}') q;</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ERROR:  value too long for type character(2)
+</programlisting>
+        <literal>select jsonb_populate_record_valid(NULL::jsb_char2, '{"a": "aa"}');</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ jsonb_populate_record_valid
+-----------------------------
+ t
+(1 row)
+</programlisting>
+
+        <literal>select * from jsonb_populate_record(NULL::jsb_char2, '{"a": "aa"}') q;</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ a
+----
+ aa
+(1 row)
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_populate_recordset</primary>
+        </indexterm>
+        <function>json_populate_recordset</function> ( <parameter>base</parameter> <type>anyelement</type>, <parameter>from_json</parameter> <type>json</type> )
+        <returnvalue>setof anyelement</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_populate_recordset</primary>
+        </indexterm>
+        <function>jsonb_populate_recordset</function> ( <parameter>base</parameter> <type>anyelement</type>, <parameter>from_json</parameter> <type>jsonb</type> )
+        <returnvalue>setof anyelement</returnvalue>
+       </para>
+       <para>
+        Expands the top-level JSON array of objects to a set of rows having
+        the composite type of the <parameter>base</parameter> argument.
+        Each element of the JSON array is processed as described above
+        for <function>json[b]_populate_record</function>.
+       </para>
+       <para>
+        <literal>create type twoints as (a int, b int);</literal>
+       </para>
+       <para>
+        <literal>select * from json_populate_recordset(null::twoints, '[{"a":1,"b":2}, {"a":3,"b":4}]')</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ a | b
+---+---
+ 1 | 2
+ 3 | 4
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_to_record</primary>
+        </indexterm>
+        <function>json_to_record</function> ( <type>json</type> )
+        <returnvalue>record</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_to_record</primary>
+        </indexterm>
+        <function>jsonb_to_record</function> ( <type>jsonb</type> )
+        <returnvalue>record</returnvalue>
+       </para>
+       <para>
+        Expands the top-level JSON object to a row having the composite type
+        defined by an <literal>AS</literal> clause.  (As with all functions
+        returning <type>record</type>, the calling query must explicitly
+        define the structure of the record with an <literal>AS</literal>
+        clause.)  The output record is filled from fields of the JSON object,
+        in the same way as described above
+        for <function>json[b]_populate_record</function>.  Since there is no
+        input record value, unmatched columns are always filled with nulls.
+       </para>
+       <para>
+        <literal>create type myrowtype as (a int, b text);</literal>
+       </para>
+       <para>
+        <literal>select * from json_to_record('{"a":1,"b":[1,2,3],"c":[1,2,3],"e":"bar","r": {"a": 123, "b": "a b c"}}') as x(a int, b text, c int[], d text, r myrowtype)</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ a |    b    |    c    | d |       r
+---+---------+---------+---+---------------
+ 1 | [1,2,3] | {1,2,3} |   | (123,"a b c")
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_to_recordset</primary>
+        </indexterm>
+        <function>json_to_recordset</function> ( <type>json</type> )
+        <returnvalue>setof record</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_to_recordset</primary>
+        </indexterm>
+        <function>jsonb_to_recordset</function> ( <type>jsonb</type> )
+        <returnvalue>setof record</returnvalue>
+       </para>
+       <para>
+        Expands the top-level JSON array of objects to a set of rows having
+        the composite type defined by an <literal>AS</literal> clause.  (As
+        with all functions returning <type>record</type>, the calling query
+        must explicitly define the structure of the record with
+        an <literal>AS</literal> clause.)  Each element of the JSON array is
+        processed as described above
+        for <function>json[b]_populate_record</function>.
+       </para>
+       <para>
+        <literal>select * from json_to_recordset('[{"a":1,"b":"foo"}, {"a":"2","c":"bar"}]') as x(a int, b text)</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ a |  b
+---+-----
+ 1 | foo
+ 2 |
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>jsonb_set</primary>
+        </indexterm>
+        <function>jsonb_set</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>text[]</type>, <parameter>new_value</parameter> <type>jsonb</type> <optional>, <parameter>create_if_missing</parameter> <type>boolean</type> </optional> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Returns <parameter>target</parameter>
+        with the item designated by <parameter>path</parameter>
+        replaced by <parameter>new_value</parameter>, or with
+        <parameter>new_value</parameter> added if
+        <parameter>create_if_missing</parameter> is true (which is the
+        default) and the item designated by <parameter>path</parameter>
+        does not exist.
+        All earlier steps in the path must exist, or
+        the <parameter>target</parameter> is returned unchanged.
+        As with the path oriented operators, negative integers that
+        appear in the <parameter>path</parameter> count from the end
+        of JSON arrays.
+        If the last path step is an array index that is out of range,
+        and <parameter>create_if_missing</parameter> is true, the new
+        value is added at the beginning of the array if the index is negative,
+        or at the end of the array if it is positive.
+       </para>
+       <para>
+        <literal>jsonb_set('[{"f1":1,"f2":null},2,null,3]', '{0,f1}', '[2,3,4]', false)</literal>
+        <returnvalue>[{"f1": [2, 3, 4], "f2": null}, 2, null, 3]</returnvalue>
+       </para>
+       <para>
+        <literal>jsonb_set('[{"f1":1,"f2":null},2]', '{0,f3}', '[2,3,4]')</literal>
+        <returnvalue>[{"f1": 1, "f2": null, "f3": [2, 3, 4]}, 2]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>jsonb_set_lax</primary>
+        </indexterm>
+        <function>jsonb_set_lax</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>text[]</type>, <parameter>new_value</parameter> <type>jsonb</type> <optional>, <parameter>create_if_missing</parameter> <type>boolean</type> <optional>, <parameter>null_value_treatment</parameter> <type>text</type> </optional></optional> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        If <parameter>new_value</parameter> is not <literal>NULL</literal>,
+        behaves identically to <literal>jsonb_set</literal>. Otherwise behaves
+        according to the value
+        of <parameter>null_value_treatment</parameter> which must be one
+        of <literal>'raise_exception'</literal>,
+        <literal>'use_json_null'</literal>, <literal>'delete_key'</literal>, or
+        <literal>'return_target'</literal>. The default is
+        <literal>'use_json_null'</literal>.
+       </para>
+       <para>
+        <literal>jsonb_set_lax('[{"f1":1,"f2":null},2,null,3]', '{0,f1}', null)</literal>
+        <returnvalue>[{"f1": null, "f2": null}, 2, null, 3]</returnvalue>
+       </para>
+       <para>
+        <literal>jsonb_set_lax('[{"f1":99,"f2":null},2]', '{0,f3}', null, true, 'return_target')</literal>
+        <returnvalue>[{"f1": 99, "f2": null}, 2]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>jsonb_insert</primary>
+        </indexterm>
+        <function>jsonb_insert</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>text[]</type>, <parameter>new_value</parameter> <type>jsonb</type> <optional>, <parameter>insert_after</parameter> <type>boolean</type> </optional> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Returns <parameter>target</parameter>
+        with <parameter>new_value</parameter> inserted.  If the item
+        designated by the <parameter>path</parameter> is an array
+        element, <parameter>new_value</parameter> will be inserted before
+        that item if <parameter>insert_after</parameter> is false (which
+        is the default), or after it
+        if <parameter>insert_after</parameter> is true.  If the item
+        designated by the <parameter>path</parameter> is an object
+        field, <parameter>new_value</parameter> will be inserted only if
+        the object does not already contain that key.
+        All earlier steps in the path must exist, or
+        the <parameter>target</parameter> is returned unchanged.
+        As with the path oriented operators, negative integers that
+        appear in the <parameter>path</parameter> count from the end
+        of JSON arrays.
+        If the last path step is an array index that is out of range, the new
+        value is added at the beginning of the array if the index is negative,
+        or at the end of the array if it is positive.
+       </para>
+       <para>
+        <literal>jsonb_insert('{"a": [0,1,2]}', '{a, 1}', '"new_value"')</literal>
+        <returnvalue>{"a": [0, "new_value", 1, 2]}</returnvalue>
+       </para>
+       <para>
+        <literal>jsonb_insert('{"a": [0,1,2]}', '{a, 1}', '"new_value"', true)</literal>
+        <returnvalue>{"a": [0, 1, "new_value", 2]}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_strip_nulls</primary>
+        </indexterm>
+        <function>json_strip_nulls</function> ( <parameter>target</parameter> <type>json</type> <optional>,<parameter>strip_in_arrays</parameter> <type>boolean</type> </optional> )
+        <returnvalue>json</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_strip_nulls</primary>
+        </indexterm>
+        <function>jsonb_strip_nulls</function> ( <parameter>target</parameter> <type>jsonb</type> <optional>,<parameter>strip_in_arrays</parameter> <type>boolean</type> </optional> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Deletes all object fields that have null values from the given JSON
+        value, recursively.
+        If <parameter>strip_in_arrays</parameter> is true (the default is false),
+        null array elements are also stripped.
+        Otherwise they are not stripped. Bare null values are never stripped.
+       </para>
+       <para>
+        <literal>json_strip_nulls('[{"f1":1, "f2":null}, 2, null, 3]')</literal>
+        <returnvalue>[{"f1":1},2,null,3]</returnvalue>
+       </para>
+       <para>
+        <literal>jsonb_strip_nulls('[1,2,null,3,4]', true);</literal>
+        <returnvalue>[1,2,3,4]</returnvalue>
+       </para>
+       </entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>jsonb_path_exists</primary>
+        </indexterm>
+        <function>jsonb_path_exists</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Checks whether the JSON path returns any item for the specified JSON
+        value.
+        (This is useful only with SQL-standard JSON path expressions, not
+        <link linkend="functions-sqljson-check-expressions">predicate check
+        expressions</link>, since those always return a value.)
+        If the <parameter>vars</parameter> argument is specified, it must
+        be a JSON object, and its fields provide named values to be
+        substituted into the <type>jsonpath</type> expression.
+        If the <parameter>silent</parameter> argument is specified and
+        is <literal>true</literal>, the function suppresses the same errors
+        as the <literal>@?</literal> and <literal>@@</literal> operators do.
+       </para>
+       <para>
+        <literal>jsonb_path_exists('{"a":[1,2,3,4,5]}', '$.a[*] ? (@ >= $min &amp;&amp; @ &lt;= $max)', '{"min":2, "max":4}')</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>jsonb_path_match</primary>
+        </indexterm>
+        <function>jsonb_path_match</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Returns the SQL boolean result of a JSON path predicate check
+        for the specified JSON value.
+        (This is useful only
+        with <link linkend="functions-sqljson-check-expressions">predicate
+        check expressions</link>, not SQL-standard JSON path expressions,
+        since it will either fail or return <literal>NULL</literal> if the
+        path result is not a single boolean value.)
+        The optional <parameter>vars</parameter>
+        and <parameter>silent</parameter> arguments act the same as
+        for <function>jsonb_path_exists</function>.
+       </para>
+       <para>
+        <literal>jsonb_path_match('{"a":[1,2,3,4,5]}', 'exists($.a[*] ? (@ >= $min &amp;&amp; @ &lt;= $max))', '{"min":2, "max":4}')</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>jsonb_path_query</primary>
+        </indexterm>
+        <function>jsonb_path_query</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
+        <returnvalue>setof jsonb</returnvalue>
+       </para>
+       <para>
+        Returns all JSON items returned by the JSON path for the specified
+        JSON value.
+        For SQL-standard JSON path expressions it returns the JSON
+        values selected from <parameter>target</parameter>.
+        For <link linkend="functions-sqljson-check-expressions">predicate
+        check expressions</link> it returns the result of the predicate
+        check: <literal>true</literal>, <literal>false</literal>,
+        or <literal>null</literal>.
+        The optional <parameter>vars</parameter>
+        and <parameter>silent</parameter> arguments act the same as
+        for <function>jsonb_path_exists</function>.
+       </para>
+       <para>
+        <literal>select * from jsonb_path_query('{"a":[1,2,3,4,5]}', '$.a[*] ? (@ >= $min &amp;&amp; @ &lt;= $max)', '{"min":2, "max":4}')</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ jsonb_path_query
+------------------
+ 2
+ 3
+ 4
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>jsonb_path_query_array</primary>
+        </indexterm>
+        <function>jsonb_path_query_array</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Returns all JSON items returned by the JSON path for the specified
+        JSON value, as a JSON array.
+        The parameters are the same as
+        for <function>jsonb_path_query</function>.
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('{"a":[1,2,3,4,5]}', '$.a[*] ? (@ >= $min &amp;&amp; @ &lt;= $max)', '{"min":2, "max":4}')</literal>
+        <returnvalue>[2, 3, 4]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>jsonb_path_query_first</primary>
+        </indexterm>
+        <function>jsonb_path_query_first</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        Returns the first JSON item returned by the JSON path for the
+        specified JSON value, or <literal>NULL</literal> if there are no
+        results.
+        The parameters are the same as
+        for <function>jsonb_path_query</function>.
+       </para>
+       <para>
+        <literal>jsonb_path_query_first('{"a":[1,2,3,4,5]}', '$.a[*] ? (@ >= $min &amp;&amp; @ &lt;= $max)', '{"min":2, "max":4}')</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>jsonb_path_exists_tz</primary>
+        </indexterm>
+        <function>jsonb_path_exists_tz</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_path_match_tz</primary>
+        </indexterm>
+        <function>jsonb_path_match_tz</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_path_query_tz</primary>
+        </indexterm>
+        <function>jsonb_path_query_tz</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
+        <returnvalue>setof jsonb</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_path_query_array_tz</primary>
+        </indexterm>
+        <function>jsonb_path_query_array_tz</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_path_query_first_tz</primary>
+        </indexterm>
+        <function>jsonb_path_query_first_tz</function> ( <parameter>target</parameter> <type>jsonb</type>, <parameter>path</parameter> <type>jsonpath</type> <optional>, <parameter>vars</parameter> <type>jsonb</type> <optional>, <parameter>silent</parameter> <type>boolean</type> </optional></optional> )
+        <returnvalue>jsonb</returnvalue>
+       </para>
+       <para>
+        These functions act like their counterparts described above without
+        the <literal>_tz</literal> suffix, except that these functions support
+        comparisons of date/time values that require timezone-aware
+        conversions.  The example below requires interpretation of the
+        date-only value <literal>2015-08-02</literal> as a timestamp with time
+        zone, so the result depends on the current
+        <xref linkend="guc-timezone"/> setting.  Due to this dependency, these
+        functions are marked as stable, which means these functions cannot be
+        used in indexes.  Their counterparts are immutable, and so can be used
+        in indexes; but they will throw errors if asked to make such
+        comparisons.
+       </para>
+       <para>
+        <literal>jsonb_path_exists_tz('["2015-08-01 12:00:00-05"]', '$[*] ? (@.datetime() &lt; "2015-08-02".datetime())')</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>jsonb_pretty</primary>
+        </indexterm>
+        <function>jsonb_pretty</function> ( <type>jsonb</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts the given JSON value to pretty-printed, indented text.
+       </para>
+       <para>
+        <literal>jsonb_pretty('[{"f1":1,"f2":null}, 2]')</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+[
+    {
+        "f1": 1,
+        "f2": null
+    },
+    2
+]
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_typeof</primary>
+        </indexterm>
+        <function>json_typeof</function> ( <type>json</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_typeof</primary>
+        </indexterm>
+        <function>jsonb_typeof</function> ( <type>jsonb</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the type of the top-level JSON value as a text string.
+        Possible types are
+        <literal>object</literal>, <literal>array</literal>,
+        <literal>string</literal>, <literal>number</literal>,
+        <literal>boolean</literal>, and <literal>null</literal>.
+        (The <literal>null</literal> result should not be confused
+        with an SQL NULL; see the examples.)
+       </para>
+       <para>
+        <literal>json_typeof('-123.4')</literal>
+        <returnvalue>number</returnvalue>
+       </para>
+       <para>
+        <literal>json_typeof('null'::json)</literal>
+        <returnvalue>null</returnvalue>
+       </para>
+       <para>
+        <literal>json_typeof(NULL::json) IS NULL</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+ </sect2>
+
+ <sect2 id="functions-sqljson-path">
+  <title>The SQL/JSON Path Language</title>
+
+  <indexterm zone="functions-sqljson-path">
+   <primary>SQL/JSON path language</primary>
+  </indexterm>
+
+  <para>
+   SQL/JSON path expressions specify item(s) to be retrieved
+   from a JSON value, similarly to XPath expressions used
+   for access to XML content. In <productname>PostgreSQL</productname>,
+   path expressions are implemented as the <type>jsonpath</type>
+   data type and can use any elements described in
+   <xref linkend="datatype-jsonpath"/>.
+  </para>
+
+  <para>
+   JSON query functions and operators
+   pass the provided path expression to the <firstterm>path engine</firstterm>
+   for evaluation. If the expression matches the queried JSON data,
+   the corresponding JSON item, or set of items, is returned.
+   If there is no match, the result will be <literal>NULL</literal>,
+   <literal>false</literal>, or an error, depending on the function.
+   Path expressions are written in the SQL/JSON path language
+   and can include arithmetic expressions and functions.
+  </para>
+
+  <para>
+   A path expression consists of a sequence of elements allowed
+   by the <type>jsonpath</type> data type.
+   The path expression is normally evaluated from left to right, but
+   you can use parentheses to change the order of operations.
+   If the evaluation is successful, a sequence of JSON items is produced,
+   and the evaluation result is returned to the JSON query function
+   that completes the specified computation.
+  </para>
+
+  <para>
+   To refer to the JSON value being queried (the
+   <firstterm>context item</firstterm>), use the <literal>$</literal> variable
+   in the path expression. The first element of a path must always
+   be <literal>$</literal>. It can be followed by one or more
+   <link linkend="type-jsonpath-accessors">accessor operators</link>,
+   which go down the JSON structure level by level to retrieve sub-items
+   of the context item. Each accessor operator acts on the
+   result(s) of the previous evaluation step, producing zero, one, or more
+   output items from each input item.
+  </para>
+
+  <para>
+   For example, suppose you have some JSON data from a GPS tracker that you
+   would like to parse, such as:
+<programlisting>
+SELECT '{
+  "track": {
+    "segments": [
+      {
+        "location":   [ 47.763, 13.4034 ],
+        "start time": "2018-10-14 10:05:14",
+        "HR": 73
+      },
+      {
+        "location":   [ 47.706, 13.2635 ],
+        "start time": "2018-10-14 10:39:21",
+        "HR": 135
+      }
+    ]
+  }
+}' AS json \gset
+</programlisting>
+   (The above example can be copied-and-pasted
+   into <application>psql</application> to set things up for the following
+   examples.  Then <application>psql</application> will
+   expand <literal>:'json'</literal> into a suitably-quoted string
+   constant containing the JSON value.)
+  </para>
+
+  <para>
+   To retrieve the available track segments, you need to use the
+   <literal>.<replaceable>key</replaceable></literal> accessor
+   operator to descend through surrounding JSON objects, for example:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments');</userinput>
+                                                                         jsonb_path_query
+-----------------------------------------------------------&zwsp;-----------------------------------------------------------&zwsp;---------------------------------------------
+ [{"HR": 73, "location": [47.763, 13.4034], "start time": "2018-10-14 10:05:14"}, {"HR": 135, "location": [47.706, 13.2635], "start time": "2018-10-14 10:39:21"}]
+</screen>
+  </para>
+
+  <para>
+   To retrieve the contents of an array, you typically use the
+   <literal>[*]</literal> operator.
+   The following example will return the location coordinates for all
+   the available track segments:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments[*].location');</userinput>
+ jsonb_path_query
+-------------------
+ [47.763, 13.4034]
+ [47.706, 13.2635]
+</screen>
+   Here we started with the whole JSON input value (<literal>$</literal>),
+   then the <literal>.track</literal> accessor selected the JSON object
+   associated with the <literal>"track"</literal> object key, then
+   the <literal>.segments</literal> accessor selected the JSON array
+   associated with the <literal>"segments"</literal> key within that
+   object, then the <literal>[*]</literal> accessor selected each element
+   of that array (producing a series of items), then
+   the <literal>.location</literal> accessor selected the JSON array
+   associated with the <literal>"location"</literal> key within each of
+   those objects.  In this example, each of those objects had
+   a <literal>"location"</literal> key; but if any of them did not,
+   the <literal>.location</literal> accessor would have simply produced no
+   output for that input item.
+  </para>
+
+  <para>
+   To return the coordinates of the first segment only, you can
+   specify the corresponding subscript in the <literal>[]</literal>
+   accessor operator. Recall that JSON array indexes are 0-relative:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments[0].location');</userinput>
+ jsonb_path_query
+-------------------
+ [47.763, 13.4034]
+</screen>
+  </para>
+
+  <para>
+   The result of each path evaluation step can be processed
+   by one or more of the <type>jsonpath</type> operators and methods
+   listed in <xref linkend="functions-sqljson-path-operators"/>.
+   Each method name must be preceded by a dot. For example,
+   you can get the size of an array:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments.size()');</userinput>
+ jsonb_path_query
+------------------
+ 2
+</screen>
+   More examples of using <type>jsonpath</type> operators
+   and methods within path expressions appear below in
+   <xref linkend="functions-sqljson-path-operators"/>.
+  </para>
+
+  <para>
+   A path can also contain
+   <firstterm>filter expressions</firstterm> that work similarly to the
+   <literal>WHERE</literal> clause in SQL. A filter expression begins with
+   a question mark and provides a condition in parentheses:
+
+<synopsis>
+? (<replaceable>condition</replaceable>)
+</synopsis>
+  </para>
+
+  <para>
+   Filter expressions must be written just after the path evaluation step
+   to which they should apply. The result of that step is filtered to include
+   only those items that satisfy the provided condition. SQL/JSON defines
+   three-valued logic, so the condition can
+   produce <literal>true</literal>, <literal>false</literal>,
+   or <literal>unknown</literal>. The <literal>unknown</literal> value
+   plays the same role as SQL <literal>NULL</literal> and can be tested
+   for with the <literal>is unknown</literal> predicate. Further path
+   evaluation steps use only those items for which the filter expression
+   returned <literal>true</literal>.
+  </para>
+
+  <para>
+   The functions and operators that can be used in filter expressions are
+   listed in <xref linkend="functions-sqljson-filter-ex-table"/>.  Within a
+   filter expression, the <literal>@</literal> variable denotes the value
+   being considered (i.e., one result of the preceding path step).  You can
+   write accessor operators after <literal>@</literal> to retrieve component
+   items.
+  </para>
+
+  <para>
+   For example, suppose you would like to retrieve all heart rate values higher
+   than 130. You can achieve this as follows:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments[*].HR ? (@ &gt; 130)');</userinput>
+ jsonb_path_query
+------------------
+ 135
+</screen>
+  </para>
+
+  <para>
+   To get the start times of segments with such values, you have to
+   filter out irrelevant segments before selecting the start times, so the
+   filter expression is applied to the previous step, and the path used
+   in the condition is different:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments[*] ? (@.HR &gt; 130)."start time"');</userinput>
+   jsonb_path_query
+-----------------------
+ "2018-10-14 10:39:21"
+</screen>
+  </para>
+
+  <para>
+   You can use several filter expressions in sequence, if required.
+   The following example selects start times of all segments that
+   contain locations with relevant coordinates and high heart rate values:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments[*] ? (@.location[1] &lt; 13.4) ? (@.HR &gt; 130)."start time"');</userinput>
+   jsonb_path_query
+-----------------------
+ "2018-10-14 10:39:21"
+</screen>
+  </para>
+
+  <para>
+   Using filter expressions at different nesting levels is also allowed.
+   The following example first filters all segments by location, and then
+   returns high heart rate values for these segments, if available:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments[*] ? (@.location[1] &lt; 13.4).HR ? (@ &gt; 130)');</userinput>
+ jsonb_path_query
+------------------
+ 135
+</screen>
+  </para>
+
+  <para>
+   You can also nest filter expressions within each other.
+   This example returns the size of the track if it contains any
+   segments with high heart rate values, or an empty sequence otherwise:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track ? (exists(@.segments[*] ? (@.HR &gt; 130))).segments.size()');</userinput>
+ jsonb_path_query
+------------------
+ 2
+</screen>
+  </para>
+
+  <sect3 id="functions-sqljson-deviations">
+  <title>Deviations from the SQL Standard</title>
+   <para>
+    <productname>PostgreSQL</productname>'s implementation of the SQL/JSON path
+    language has the following deviations from the SQL/JSON standard.
+   </para>
+
+   <sect4 id="functions-sqljson-check-expressions">
+   <title>Boolean Predicate Check Expressions</title>
+    <para>
+     As an extension to the SQL standard,
+     a <productname>PostgreSQL</productname> path expression can be a
+     Boolean predicate, whereas the SQL standard allows predicates only within
+     filters. While SQL-standard path expressions return the relevant
+     element(s) of the queried JSON value, predicate check expressions
+     return the single three-valued <type>jsonb</type> result of the
+     predicate: <literal>true</literal>,
+     <literal>false</literal>, or <literal>null</literal>.
+     For example, we could write this SQL-standard filter expression:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments ?(@[*].HR &gt; 130)');</userinput>
+                                jsonb_path_query
+-----------------------------------------------------------&zwsp;----------------------
+ {"HR": 135, "location": [47.706, 13.2635], "start time": "2018-10-14 10:39:21"}
+</screen>
+     The similar predicate check expression simply
+     returns <literal>true</literal>, indicating that a match exists:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', '$.track.segments[*].HR &gt; 130');</userinput>
+ jsonb_path_query
+------------------
+ true
+</screen>
+     </para>
+
+     <note>
+      <para>
+       Predicate check expressions are required in the
+       <literal>@@</literal> operator (and the
+       <function>jsonb_path_match</function> function), and should not be used
+       with the <literal>@?</literal> operator (or the
+       <function>jsonb_path_exists</function> function).
+      </para>
+     </note>
+    </sect4>
+
+    <sect4 id="functions-sqljson-regular-expression-deviation">
+    <title>Regular Expression Interpretation</title>
+     <para>
+      There are minor differences in the interpretation of regular
+      expression patterns used in <literal>like_regex</literal> filters, as
+      described in <xref linkend="jsonpath-regular-expressions"/>.
+     </para>
+    </sect4>
+   </sect3>
+
+   <sect3 id="functions-sqljson-strict-and-lax-modes">
+   <title>Strict and Lax Modes</title>
+    <para>
+     When you query JSON data, the path expression may not match the
+     actual JSON data structure. An attempt to access a non-existent
+     member of an object or element of an array is defined as a
+     structural error. SQL/JSON path expressions have two modes
+     of handling structural errors:
+    </para>
+
+   <itemizedlist>
+    <listitem>
+     <para>
+      lax (default) &mdash; the path engine implicitly adapts
+      the queried data to the specified path.
+      Any structural errors that cannot be fixed as described below
+      are suppressed, producing no match.
+     </para>
+    </listitem>
+    <listitem>
+     <para>
+      strict &mdash; if a structural error occurs, an error is raised.
+     </para>
+    </listitem>
+   </itemizedlist>
+
+   <para>
+    Lax mode facilitates matching of a JSON document and path
+    expression when the JSON data does not conform to the expected schema.
+    If an operand does not match the requirements of a particular operation,
+    it can be automatically wrapped as an SQL/JSON array, or unwrapped by
+    converting its elements into an SQL/JSON sequence before performing
+    the operation. Also, comparison operators automatically unwrap their
+    operands in lax mode, so you can compare SQL/JSON arrays
+    out-of-the-box. An array of size 1 is considered equal to its sole element.
+    Automatic unwrapping is not performed when:
+    <itemizedlist>
+     <listitem>
+      <para>
+       The path expression contains <literal>type()</literal> or
+       <literal>size()</literal> methods that return the type
+       and the number of elements in the array, respectively.
+      </para>
+     </listitem>
+     <listitem>
+      <para>
+       The queried JSON data contain nested arrays. In this case, only
+       the outermost array is unwrapped, while all the inner arrays
+       remain unchanged. Thus, implicit unwrapping can only go one
+       level down within each path evaluation step.
+      </para>
+     </listitem>
+    </itemizedlist>
+   </para>
+
+   <para>
+    For example, when querying the GPS data listed above, you can
+    abstract from the fact that it stores an array of segments
+    when using lax mode:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', 'lax $.track.segments.location');</userinput>
+ jsonb_path_query
+-------------------
+ [47.763, 13.4034]
+ [47.706, 13.2635]
+</screen>
+   </para>
+
+   <para>
+    In strict mode, the specified path must exactly match the structure of
+    the queried JSON document, so using this path
+    expression will cause an error:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', 'strict $.track.segments.location');</userinput>
+ERROR:  jsonpath member accessor can only be applied to an object
+</screen>
+    To get the same result as in lax mode, you have to explicitly unwrap the
+    <literal>segments</literal> array:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', 'strict $.track.segments[*].location');</userinput>
+ jsonb_path_query
+-------------------
+ [47.763, 13.4034]
+ [47.706, 13.2635]
+</screen>
+   </para>
+
+   <para>
+    The unwrapping behavior of lax mode can lead to surprising results. For
+    instance, the following query using the <literal>.**</literal> accessor
+    selects every <literal>HR</literal> value twice:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', 'lax $.**.HR');</userinput>
+ jsonb_path_query
+------------------
+ 73
+ 135
+ 73
+ 135
+</screen>
+    This happens because the <literal>.**</literal> accessor selects both
+    the <literal>segments</literal> array and each of its elements, while
+    the <literal>.HR</literal> accessor automatically unwraps arrays when
+    using lax mode. To avoid surprising results, we recommend using
+    the <literal>.**</literal> accessor only in strict mode. The
+    following query selects each <literal>HR</literal> value just once:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', 'strict $.**.HR');</userinput>
+ jsonb_path_query
+------------------
+ 73
+ 135
+</screen>
+   </para>
+
+   <para>
+    The unwrapping of arrays can also lead to unexpected results. Consider this
+    example, which selects all the <literal>location</literal> arrays:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', 'lax $.track.segments[*].location');</userinput>
+ jsonb_path_query
+-------------------
+ [47.763, 13.4034]
+ [47.706, 13.2635]
+(2 rows)
+</screen>
+    As expected it returns the full arrays. But applying a filter expression
+    causes the arrays to be unwrapped to evaluate each item, returning only the
+    items that match the expression:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', 'lax $.track.segments[*].location ?(@[*] &gt; 15)');</userinput>
+ jsonb_path_query
+------------------
+ 47.763
+ 47.706
+(2 rows)
+</screen>
+    This despite the fact that the full arrays are selected by the path
+    expression. Use strict mode to restore selecting the arrays:
+<screen>
+<prompt>=&gt;</prompt> <userinput>select jsonb_path_query(:'json', 'strict $.track.segments[*].location ?(@[*] &gt; 15)');</userinput>
+ jsonb_path_query
+-------------------
+ [47.763, 13.4034]
+ [47.706, 13.2635]
+(2 rows)
+</screen>
+   </para>
+   </sect3>
+
+   <sect3 id="functions-sqljson-path-operators">
+   <title>SQL/JSON Path Operators and Methods</title>
+
+   <para>
+    <xref linkend="functions-sqljson-op-table"/> shows the operators and
+    methods available in <type>jsonpath</type>.  Note that while the unary
+    operators and methods can be applied to multiple values resulting from a
+    preceding path step, the binary operators (addition etc.) can only be
+    applied to single values.  In lax mode, methods applied to an array will be
+    executed for each value in the array.  The exceptions are
+    <literal>.type()</literal> and <literal>.size()</literal>, which apply to
+    the array itself.
+   </para>
+
+   <table id="functions-sqljson-op-table">
+    <title><type>jsonpath</type> Operators and Methods</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Operator/Method
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>number</replaceable> <literal>+</literal> <replaceable>number</replaceable>
+        <returnvalue><replaceable>number</replaceable></returnvalue>
+       </para>
+       <para>
+        Addition
+       </para>
+       <para>
+        <literal>jsonb_path_query('[2]', '$[0] + 3')</literal>
+        <returnvalue>5</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>+</literal> <replaceable>number</replaceable>
+        <returnvalue><replaceable>number</replaceable></returnvalue>
+       </para>
+       <para>
+        Unary plus (no operation); unlike addition, this can iterate over
+        multiple values
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('{"x": [2,3,4]}', '+ $.x')</literal>
+        <returnvalue>[2, 3, 4]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>number</replaceable> <literal>-</literal> <replaceable>number</replaceable>
+        <returnvalue><replaceable>number</replaceable></returnvalue>
+       </para>
+       <para>
+        Subtraction
+       </para>
+       <para>
+        <literal>jsonb_path_query('[2]', '7 - $[0]')</literal>
+        <returnvalue>5</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>-</literal> <replaceable>number</replaceable>
+        <returnvalue><replaceable>number</replaceable></returnvalue>
+       </para>
+       <para>
+        Negation; unlike subtraction, this can iterate over
+        multiple values
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('{"x": [2,3,4]}', '- $.x')</literal>
+        <returnvalue>[-2, -3, -4]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>number</replaceable> <literal>*</literal> <replaceable>number</replaceable>
+        <returnvalue><replaceable>number</replaceable></returnvalue>
+       </para>
+       <para>
+        Multiplication
+       </para>
+       <para>
+        <literal>jsonb_path_query('[4]', '2 * $[0]')</literal>
+        <returnvalue>8</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>number</replaceable> <literal>/</literal> <replaceable>number</replaceable>
+        <returnvalue><replaceable>number</replaceable></returnvalue>
+       </para>
+       <para>
+        Division
+       </para>
+       <para>
+        <literal>jsonb_path_query('[8.5]', '$[0] / 2')</literal>
+        <returnvalue>4.2500000000000000</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>number</replaceable> <literal>%</literal> <replaceable>number</replaceable>
+        <returnvalue><replaceable>number</replaceable></returnvalue>
+       </para>
+       <para>
+        Modulo (remainder)
+       </para>
+       <para>
+        <literal>jsonb_path_query('[32]', '$[0] % 10')</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>value</replaceable> <literal>.</literal> <literal>type()</literal>
+        <returnvalue><replaceable>string</replaceable></returnvalue>
+       </para>
+       <para>
+        Type of the JSON item (see <function>json_typeof</function>)
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('[1, "2", {}]', '$[*].type()')</literal>
+        <returnvalue>["number", "string", "object"]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>value</replaceable> <literal>.</literal> <literal>size()</literal>
+        <returnvalue><replaceable>number</replaceable></returnvalue>
+       </para>
+       <para>
+        Size of the JSON item (number of array elements, or 1 if not an
+        array)
+       </para>
+       <para>
+        <literal>jsonb_path_query('{"m": [11, 15]}', '$.m.size()')</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>value</replaceable> <literal>.</literal> <literal>boolean()</literal>
+        <returnvalue><replaceable>boolean</replaceable></returnvalue>
+       </para>
+       <para>
+        Boolean value converted from a JSON boolean, number, or string
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('[1, "yes", false]', '$[*].boolean()')</literal>
+        <returnvalue>[true, true, false]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>value</replaceable> <literal>.</literal> <literal>string()</literal>
+        <returnvalue><replaceable>string</replaceable></returnvalue>
+       </para>
+       <para>
+        String value converted from a JSON boolean, number, string, or
+        datetime
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('[1.23, "xyz", false]', '$[*].string()')</literal>
+        <returnvalue>["1.23", "xyz", "false"]</returnvalue>
+       </para>
+       <para>
+        <literal>jsonb_path_query('"2023-08-15 12:34:56"', '$.timestamp().string()')</literal>
+        <returnvalue>"2023-08-15T12:34:56"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>value</replaceable> <literal>.</literal> <literal>double()</literal>
+        <returnvalue><replaceable>number</replaceable></returnvalue>
+       </para>
+       <para>
+        Approximate floating-point number converted from a JSON number or
+        string
+       </para>
+       <para>
+        <literal>jsonb_path_query('{"len": "1.9"}', '$.len.double() * 2')</literal>
+        <returnvalue>3.8</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>number</replaceable> <literal>.</literal> <literal>ceiling()</literal>
+        <returnvalue><replaceable>number</replaceable></returnvalue>
+       </para>
+       <para>
+        Nearest integer greater than or equal to the given number
+       </para>
+       <para>
+        <literal>jsonb_path_query('{"h": 1.3}', '$.h.ceiling()')</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>number</replaceable> <literal>.</literal> <literal>floor()</literal>
+        <returnvalue><replaceable>number</replaceable></returnvalue>
+       </para>
+       <para>
+        Nearest integer less than or equal to the given number
+       </para>
+       <para>
+        <literal>jsonb_path_query('{"h": 1.7}', '$.h.floor()')</literal>
+        <returnvalue>1</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>number</replaceable> <literal>.</literal> <literal>abs()</literal>
+        <returnvalue><replaceable>number</replaceable></returnvalue>
+       </para>
+       <para>
+        Absolute value of the given number
+       </para>
+       <para>
+        <literal>jsonb_path_query('{"z": -0.3}', '$.z.abs()')</literal>
+        <returnvalue>0.3</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>value</replaceable> <literal>.</literal> <literal>bigint()</literal>
+        <returnvalue><replaceable>bigint</replaceable></returnvalue>
+       </para>
+       <para>
+        Big integer value converted from a JSON number or string
+       </para>
+       <para>
+        <literal>jsonb_path_query('{"len": "9876543219"}', '$.len.bigint()')</literal>
+        <returnvalue>9876543219</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>value</replaceable> <literal>.</literal> <literal>decimal( [ <replaceable>precision</replaceable> [ , <replaceable>scale</replaceable> ] ] )</literal>
+        <returnvalue><replaceable>decimal</replaceable></returnvalue>
+       </para>
+       <para>
+        Rounded decimal value converted from a JSON number or string
+        (<literal>precision</literal> and <literal>scale</literal> must be
+        integer values)
+       </para>
+       <para>
+        <literal>jsonb_path_query('1234.5678', '$.decimal(6, 2)')</literal>
+        <returnvalue>1234.57</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>value</replaceable> <literal>.</literal> <literal>integer()</literal>
+        <returnvalue><replaceable>integer</replaceable></returnvalue>
+       </para>
+       <para>
+        Integer value converted from a JSON number or string
+       </para>
+       <para>
+        <literal>jsonb_path_query('{"len": "12345"}', '$.len.integer()')</literal>
+        <returnvalue>12345</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>value</replaceable> <literal>.</literal> <literal>number()</literal>
+        <returnvalue><replaceable>numeric</replaceable></returnvalue>
+       </para>
+       <para>
+        Numeric value converted from a JSON number or string
+       </para>
+       <para>
+        <literal>jsonb_path_query('{"len": "123.45"}', '$.len.number()')</literal>
+        <returnvalue>123.45</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>string</replaceable> <literal>.</literal> <literal>datetime()</literal>
+        <returnvalue><replaceable>datetime_type</replaceable></returnvalue>
+        (see note)
+       </para>
+       <para>
+        Date/time value converted from a string
+       </para>
+       <para>
+        <literal>jsonb_path_query('["2015-8-1", "2015-08-12"]', '$[*] ? (@.datetime() &lt; "2015-08-2".datetime())')</literal>
+        <returnvalue>"2015-8-1"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>string</replaceable> <literal>.</literal> <literal>datetime(<replaceable>template</replaceable>)</literal>
+        <returnvalue><replaceable>datetime_type</replaceable></returnvalue>
+        (see note)
+       </para>
+       <para>
+        Date/time value converted from a string using the
+        specified <function>to_timestamp</function> template
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('["12:30", "18:40"]', '$[*].datetime("HH24:MI")')</literal>
+        <returnvalue>["12:30:00", "18:40:00"]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>string</replaceable> <literal>.</literal> <literal>date()</literal>
+        <returnvalue><replaceable>date</replaceable></returnvalue>
+       </para>
+       <para>
+        Date value converted from a string
+       </para>
+       <para>
+        <literal>jsonb_path_query('"2023-08-15"', '$.date()')</literal>
+        <returnvalue>"2023-08-15"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>string</replaceable> <literal>.</literal> <literal>time()</literal>
+        <returnvalue><replaceable>time without time zone</replaceable></returnvalue>
+       </para>
+       <para>
+        Time without time zone value converted from a string
+       </para>
+       <para>
+        <literal>jsonb_path_query('"12:34:56"', '$.time()')</literal>
+        <returnvalue>"12:34:56"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>string</replaceable> <literal>.</literal> <literal>time(<replaceable>precision</replaceable>)</literal>
+        <returnvalue><replaceable>time without time zone</replaceable></returnvalue>
+       </para>
+       <para>
+        Time without time zone value converted from a string, with fractional
+        seconds adjusted to the given precision
+       </para>
+       <para>
+        <literal>jsonb_path_query('"12:34:56.789"', '$.time(2)')</literal>
+        <returnvalue>"12:34:56.79"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>string</replaceable> <literal>.</literal> <literal>time_tz()</literal>
+        <returnvalue><replaceable>time with time zone</replaceable></returnvalue>
+       </para>
+       <para>
+        Time with time zone value converted from a string
+       </para>
+       <para>
+        <literal>jsonb_path_query('"12:34:56 +05:30"', '$.time_tz()')</literal>
+        <returnvalue>"12:34:56+05:30"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>string</replaceable> <literal>.</literal> <literal>time_tz(<replaceable>precision</replaceable>)</literal>
+        <returnvalue><replaceable>time with time zone</replaceable></returnvalue>
+       </para>
+       <para>
+        Time with time zone value converted from a string, with fractional
+        seconds adjusted to the given precision
+       </para>
+       <para>
+        <literal>jsonb_path_query('"12:34:56.789 +05:30"', '$.time_tz(2)')</literal>
+        <returnvalue>"12:34:56.79+05:30"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>string</replaceable> <literal>.</literal> <literal>timestamp()</literal>
+        <returnvalue><replaceable>timestamp without time zone</replaceable></returnvalue>
+       </para>
+       <para>
+        Timestamp without time zone value converted from a string
+       </para>
+       <para>
+        <literal>jsonb_path_query('"2023-08-15 12:34:56"', '$.timestamp()')</literal>
+        <returnvalue>"2023-08-15T12:34:56"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>string</replaceable> <literal>.</literal> <literal>timestamp(<replaceable>precision</replaceable>)</literal>
+        <returnvalue><replaceable>timestamp without time zone</replaceable></returnvalue>
+       </para>
+       <para>
+        Timestamp without time zone value converted from a string, with
+        fractional seconds adjusted to the given precision
+       </para>
+       <para>
+        <literal>jsonb_path_query('"2023-08-15 12:34:56.789"', '$.timestamp(2)')</literal>
+        <returnvalue>"2023-08-15T12:34:56.79"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>string</replaceable> <literal>.</literal> <literal>timestamp_tz()</literal>
+        <returnvalue><replaceable>timestamp with time zone</replaceable></returnvalue>
+       </para>
+       <para>
+        Timestamp with time zone value converted from a string
+       </para>
+       <para>
+        <literal>jsonb_path_query('"2023-08-15 12:34:56 +05:30"', '$.timestamp_tz()')</literal>
+        <returnvalue>"2023-08-15T12:34:56+05:30"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>string</replaceable> <literal>.</literal> <literal>timestamp_tz(<replaceable>precision</replaceable>)</literal>
+        <returnvalue><replaceable>timestamp with time zone</replaceable></returnvalue>
+       </para>
+       <para>
+        Timestamp with time zone value converted from a string, with fractional
+        seconds adjusted to the given precision
+       </para>
+       <para>
+        <literal>jsonb_path_query('"2023-08-15 12:34:56.789 +05:30"', '$.timestamp_tz(2)')</literal>
+        <returnvalue>"2023-08-15T12:34:56.79+05:30"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>object</replaceable> <literal>.</literal> <literal>keyvalue()</literal>
+        <returnvalue><replaceable>array</replaceable></returnvalue>
+       </para>
+       <para>
+        The object's key-value pairs, represented as an array of objects
+        containing three fields: <literal>"key"</literal>,
+        <literal>"value"</literal>, and <literal>"id"</literal>;
+        <literal>"id"</literal> is a unique identifier of the object the
+        key-value pair belongs to
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('{"x": "20", "y": 32}', '$.keyvalue()')</literal>
+        <returnvalue>[{"id": 0, "key": "x", "value": "20"}, {"id": 0, "key": "y", "value": 32}]</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+    <note>
+     <para>
+      The result type of the <literal>datetime()</literal> and
+      <literal>datetime(<replaceable>template</replaceable>)</literal>
+      methods can be <type>date</type>, <type>timetz</type>, <type>time</type>,
+      <type>timestamptz</type>, or <type>timestamp</type>.
+      Both methods determine their result type dynamically.
+     </para>
+     <para>
+      The <literal>datetime()</literal> method sequentially tries to
+      match its input string to the ISO formats
+      for <type>date</type>, <type>timetz</type>, <type>time</type>,
+      <type>timestamptz</type>, and <type>timestamp</type>. It stops on
+      the first matching format and emits the corresponding data type.
+     </para>
+     <para>
+      The <literal>datetime(<replaceable>template</replaceable>)</literal>
+      method determines the result type according to the fields used in the
+      provided template string.
+     </para>
+     <para>
+      The <literal>datetime()</literal> and
+      <literal>datetime(<replaceable>template</replaceable>)</literal> methods
+      use the same parsing rules as the <literal>to_timestamp</literal> SQL
+      function does (see <xref linkend="functions-formatting"/>), with three
+      exceptions.  First, these methods don't allow unmatched template
+      patterns.  Second, only the following separators are allowed in the
+      template string: minus sign, period, solidus (slash), comma, apostrophe,
+      semicolon, colon and space.  Third, separators in the template string
+      must exactly match the input string.
+     </para>
+     <para>
+      If different date/time types need to be compared, an implicit cast is
+      applied. A <type>date</type> value can be cast to <type>timestamp</type>
+      or <type>timestamptz</type>, <type>timestamp</type> can be cast to
+      <type>timestamptz</type>, and <type>time</type> to <type>timetz</type>.
+      However, all but the first of these conversions depend on the current
+      <xref linkend="guc-timezone"/> setting, and thus can only be performed
+      within timezone-aware <type>jsonpath</type> functions.  Similarly, other
+      date/time-related methods that convert strings to date/time types
+      also do this casting, which may involve the current
+      <xref linkend="guc-timezone"/> setting. Therefore, these conversions can
+      also only be performed within timezone-aware <type>jsonpath</type>
+      functions.
+     </para>
+    </note>
+
+   <para>
+    <xref linkend="functions-sqljson-filter-ex-table"/> shows the available
+    filter expression elements.
+   </para>
+
+   <table id="functions-sqljson-filter-ex-table">
+    <title><type>jsonpath</type> Filter Expression Elements</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Predicate/Value
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>value</replaceable> <literal>==</literal> <replaceable>value</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Equality comparison (this, and the other comparison operators, work on
+        all JSON scalar values)
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('[1, "a", 1, 3]', '$[*] ? (@ == 1)')</literal>
+        <returnvalue>[1, 1]</returnvalue>
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('[1, "a", 1, 3]', '$[*] ? (@ == "a")')</literal>
+        <returnvalue>["a"]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>value</replaceable> <literal>!=</literal> <replaceable>value</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para role="func_signature">
+        <replaceable>value</replaceable> <literal>&lt;&gt;</literal> <replaceable>value</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Non-equality comparison
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('[1, 2, 1, 3]', '$[*] ? (@ != 1)')</literal>
+        <returnvalue>[2, 3]</returnvalue>
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('["a", "b", "c"]', '$[*] ? (@ &lt;&gt; "b")')</literal>
+        <returnvalue>["a", "c"]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>value</replaceable> <literal>&lt;</literal> <replaceable>value</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Less-than comparison
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('[1, 2, 3]', '$[*] ? (@ &lt; 2)')</literal>
+        <returnvalue>[1]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>value</replaceable> <literal>&lt;=</literal> <replaceable>value</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Less-than-or-equal-to comparison
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('["a", "b", "c"]', '$[*] ? (@ &lt;= "b")')</literal>
+        <returnvalue>["a", "b"]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>value</replaceable> <literal>&gt;</literal> <replaceable>value</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Greater-than comparison
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('[1, 2, 3]', '$[*] ? (@ &gt; 2)')</literal>
+        <returnvalue>[3]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>value</replaceable> <literal>&gt;=</literal> <replaceable>value</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Greater-than-or-equal-to comparison
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('[1, 2, 3]', '$[*] ? (@ &gt;= 2)')</literal>
+        <returnvalue>[2, 3]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>true</literal>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        JSON constant <literal>true</literal>
+       </para>
+       <para>
+        <literal>jsonb_path_query('[{"name": "John", "parent": false}, {"name": "Chris", "parent": true}]', '$[*] ? (@.parent == true)')</literal>
+        <returnvalue>{"name": "Chris", "parent": true}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>false</literal>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        JSON constant <literal>false</literal>
+       </para>
+       <para>
+        <literal>jsonb_path_query('[{"name": "John", "parent": false}, {"name": "Chris", "parent": true}]', '$[*] ? (@.parent == false)')</literal>
+        <returnvalue>{"name": "John", "parent": false}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>null</literal>
+        <returnvalue><replaceable>value</replaceable></returnvalue>
+       </para>
+       <para>
+        JSON constant <literal>null</literal> (note that, unlike in SQL,
+        comparison to <literal>null</literal> works normally)
+       </para>
+       <para>
+        <literal>jsonb_path_query('[{"name": "Mary", "job": null}, {"name": "Michael", "job": "driver"}]', '$[*] ? (@.job == null) .name')</literal>
+        <returnvalue>"Mary"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>boolean</replaceable> <literal>&amp;&amp;</literal> <replaceable>boolean</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Boolean AND
+       </para>
+       <para>
+        <literal>jsonb_path_query('[1, 3, 7]', '$[*] ? (@ &gt; 1 &amp;&amp; @ &lt; 5)')</literal>
+        <returnvalue>3</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>boolean</replaceable> <literal>||</literal> <replaceable>boolean</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Boolean OR
+       </para>
+       <para>
+        <literal>jsonb_path_query('[1, 3, 7]', '$[*] ? (@ &lt; 1 || @ &gt; 5)')</literal>
+        <returnvalue>7</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>!</literal> <replaceable>boolean</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Boolean NOT
+       </para>
+       <para>
+        <literal>jsonb_path_query('[1, 3, 7]', '$[*] ? (!(@ &lt; 5))')</literal>
+        <returnvalue>7</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>boolean</replaceable> <literal>is unknown</literal>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Tests whether a Boolean condition is <literal>unknown</literal>.
+       </para>
+       <para>
+        <literal>jsonb_path_query('[-1, 2, 7, "foo"]', '$[*] ? ((@ > 0) is unknown)')</literal>
+        <returnvalue>"foo"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>string</replaceable> <literal>like_regex</literal> <replaceable>string</replaceable> <optional> <literal>flag</literal> <replaceable>string</replaceable> </optional>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Tests whether the first operand matches the regular expression
+        given by the second operand, optionally with modifications
+        described by a string of <literal>flag</literal> characters (see
+        <xref linkend="jsonpath-regular-expressions"/>).
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('["abc", "abd", "aBdC", "abdacb", "babc"]', '$[*] ? (@ like_regex "^ab.*c")')</literal>
+        <returnvalue>["abc", "abdacb"]</returnvalue>
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('["abc", "abd", "aBdC", "abdacb", "babc"]', '$[*] ? (@ like_regex "^ab.*c" flag "i")')</literal>
+        <returnvalue>["abc", "aBdC", "abdacb"]</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>string</replaceable> <literal>starts with</literal> <replaceable>string</replaceable>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Tests whether the second operand is an initial substring of the first
+        operand.
+       </para>
+       <para>
+        <literal>jsonb_path_query('["John Smith", "Mary Stone", "Bob Johnson"]', '$[*] ? (@ starts with "John")')</literal>
+        <returnvalue>"John Smith"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>exists</literal> <literal>(</literal> <replaceable>path_expression</replaceable> <literal>)</literal>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Tests whether a path expression matches at least one SQL/JSON item.
+        Returns <literal>unknown</literal> if the path expression would result
+        in an error; the second example uses this to avoid a no-such-key error
+        in strict mode.
+       </para>
+       <para>
+        <literal>jsonb_path_query('{"x": [1, 2], "y": [2, 4]}', 'strict $.* ? (exists (@ ? (@[*] &gt; 2)))')</literal>
+        <returnvalue>[2, 4]</returnvalue>
+       </para>
+       <para>
+        <literal>jsonb_path_query_array('{"value": 41}', 'strict $ ? (exists (@.name)) .name')</literal>
+        <returnvalue>[]</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   </sect3>
+
+   <sect3 id="jsonpath-regular-expressions">
+    <title>SQL/JSON Regular Expressions</title>
+
+    <indexterm zone="jsonpath-regular-expressions">
+     <primary><literal>LIKE_REGEX</literal></primary>
+     <secondary>in SQL/JSON</secondary>
+    </indexterm>
+
+    <para>
+     SQL/JSON path expressions allow matching text to a regular expression
+     with the <literal>like_regex</literal> filter.  For example, the
+     following SQL/JSON path query would case-insensitively match all
+     strings in an array that start with an English vowel:
+<programlisting>
+$[*] ? (@ like_regex "^[aeiou]" flag "i")
+</programlisting>
+    </para>
+
+    <para>
+     The optional <literal>flag</literal> string may include one or more of
+     the characters
+     <literal>i</literal> for case-insensitive match,
+     <literal>m</literal> to allow <literal>^</literal>
+     and <literal>$</literal> to match at newlines,
+     <literal>s</literal> to allow <literal>.</literal> to match a newline,
+     and <literal>q</literal> to quote the whole pattern (reducing the
+     behavior to a simple substring match).
+    </para>
+
+    <para>
+     The SQL/JSON standard borrows its definition for regular expressions
+     from the <literal>LIKE_REGEX</literal> operator, which in turn uses the
+     XQuery standard.  PostgreSQL does not currently support the
+     <literal>LIKE_REGEX</literal> operator.  Therefore,
+     the <literal>like_regex</literal> filter is implemented using the
+     POSIX regular expression engine described in
+     <xref linkend="functions-posix-regexp"/>.  This leads to various minor
+     discrepancies from standard SQL/JSON behavior, which are cataloged in
+     <xref linkend="posix-vs-xquery"/>.
+     Note, however, that the flag-letter incompatibilities described there
+     do not apply to SQL/JSON, as it translates the XQuery flag letters to
+     match what the POSIX engine expects.
+    </para>
+
+    <para>
+     Keep in mind that the pattern argument of <literal>like_regex</literal>
+     is a JSON path string literal, written according to the rules given in
+     <xref linkend="datatype-jsonpath"/>.  This means in particular that any
+     backslashes you want to use in the regular expression must be doubled.
+     For example, to match string values of the root document that contain
+     only digits:
+<programlisting>
+$.* ? (@ like_regex "^\\d+$")
+</programlisting>
+    </para>
+   </sect3>
+  </sect2>
+
+   <sect2 id="sqljson-query-functions">
+    <title>SQL/JSON Query Functions</title>
+  <para>
+   SQL/JSON functions <literal>JSON_EXISTS()</literal>,
+   <literal>JSON_QUERY()</literal>, and <literal>JSON_VALUE()</literal>
+   described in <xref linkend="functions-sqljson-querying"/> can be used
+   to query JSON documents.  Each of these functions apply a
+   <replaceable>path_expression</replaceable> (an SQL/JSON path query) to a
+   <replaceable>context_item</replaceable> (the document).  See
+   <xref linkend="functions-sqljson-path"/> for more details on what
+   the <replaceable>path_expression</replaceable> can contain. The
+   <replaceable>path_expression</replaceable> can also reference variables,
+   whose values are specified with their respective names in the
+   <literal>PASSING</literal> clause that is supported by each function.
+   <replaceable>context_item</replaceable> can be a <type>jsonb</type> value
+   or a character string that can be successfully cast to <type>jsonb</type>.
+  </para>
+
+  <table id="functions-sqljson-querying">
+   <title>SQL/JSON Query Functions</title>
+   <tgroup cols="1">
+    <thead>
+     <row>
+      <entry role="func_table_entry"><para role="func_signature">
+        Function signature
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+      </para></entry>
+     </row>
+    </thead>
+    <tbody>
+     <row>
+      <entry role="func_table_entry"><para role="func_signature">
+        <indexterm><primary>json_exists</primary></indexterm>
+<synopsis>
+<function>JSON_EXISTS</function> (
+<replaceable>context_item</replaceable>, <replaceable>path_expression</replaceable>
+<optional> <literal>PASSING</literal> { <replaceable>value</replaceable> <literal>AS</literal> <replaceable>varname</replaceable> } <optional>, ...</optional></optional>
+<optional>{ <literal>TRUE</literal> | <literal>FALSE</literal> |<literal> UNKNOWN</literal> | <literal>ERROR</literal> } <literal>ON ERROR</literal> </optional>) <returnvalue>boolean</returnvalue>
+</synopsis>
+       </para>
+     <itemizedlist>
+      <listitem>
+       <para>
+        Returns true if the SQL/JSON <replaceable>path_expression</replaceable>
+        applied to the <replaceable>context_item</replaceable> yields any
+        items, false otherwise.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        The <literal>ON ERROR</literal> clause specifies the behavior if
+        an error occurs during <replaceable>path_expression</replaceable>
+        evaluation.  Specifying <literal>ERROR</literal> will cause an error to
+        be thrown with the appropriate message.  Other options include
+        returning <type>boolean</type> values <literal>FALSE</literal> or
+        <literal>TRUE</literal> or the value <literal>UNKNOWN</literal> which
+        is actually an SQL NULL. The default when no <literal>ON ERROR</literal>
+        clause is specified is to return the <type>boolean</type> value
+        <literal>FALSE</literal>.
+       </para>
+      </listitem>
+      </itemizedlist>
+       <para>
+        Examples:
+       </para>
+       <para>
+        <literal>JSON_EXISTS(jsonb '{"key1": [1,2,3]}', 'strict $.key1[*] ? (@ > $x)' PASSING 2 AS x)</literal>
+        <returnvalue>t</returnvalue>
+       </para>
+       <para>
+        <literal>JSON_EXISTS(jsonb '{"a": [1,2,3]}', 'lax $.a[5]' ERROR ON ERROR)</literal>
+        <returnvalue>f</returnvalue>
+       </para>
+       <para>
+        <literal>JSON_EXISTS(jsonb '{"a": [1,2,3]}', 'strict $.a[5]' ERROR ON ERROR)</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ERROR:  jsonpath array subscript is out of bounds
+</programlisting>
+      </para></entry>
+     </row>
+     <row>
+      <entry role="func_table_entry"><para role="func_signature">
+        <indexterm><primary>json_query</primary></indexterm>
+<synopsis>
+<function>JSON_QUERY</function> (
+<replaceable>context_item</replaceable>, <replaceable>path_expression</replaceable>
+<optional> <literal>PASSING</literal> { <replaceable>value</replaceable> <literal>AS</literal> <replaceable>varname</replaceable> } <optional>, ...</optional></optional>
+<optional> <literal>RETURNING</literal> <replaceable>data_type</replaceable> <optional> <literal>FORMAT JSON</literal> <optional> <literal>ENCODING UTF8</literal> </optional> </optional> </optional>
+<optional> { <literal>WITHOUT</literal> | <literal>WITH</literal> { <literal>CONDITIONAL</literal> | <optional><literal>UNCONDITIONAL</literal></optional> } } <optional> <literal>ARRAY</literal> </optional> <literal>WRAPPER</literal> </optional>
+<optional> { <literal>KEEP</literal> | <literal>OMIT</literal> } <literal>QUOTES</literal> <optional> <literal>ON SCALAR STRING</literal> </optional> </optional>
+<optional> { <literal>ERROR</literal> | <literal>NULL</literal> | <literal>EMPTY</literal> { <optional> <literal>ARRAY</literal> </optional> | <literal>OBJECT</literal> } | <literal>DEFAULT</literal> <replaceable>expression</replaceable> } <literal>ON EMPTY</literal> </optional>
+<optional> { <literal>ERROR</literal> | <literal>NULL</literal> | <literal>EMPTY</literal> { <optional> <literal>ARRAY</literal> </optional> | <literal>OBJECT</literal> } | <literal>DEFAULT</literal> <replaceable>expression</replaceable> } <literal>ON ERROR</literal> </optional>) <returnvalue>jsonb</returnvalue>
+</synopsis>
+      </para>
+     <itemizedlist>
+      <listitem>
+       <para>
+        Returns the result of applying the SQL/JSON
+        <replaceable>path_expression</replaceable> to the
+        <replaceable>context_item</replaceable>.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+         By default, the result is returned as a value of type <type>jsonb</type>,
+         though the <literal>RETURNING</literal> clause can be used to return
+         as some other type to which it can be successfully coerced.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        If the path expression may return multiple values, it might be necessary
+        to wrap those values using the <literal>WITH WRAPPER</literal> clause to
+        make it a valid JSON string, because the default behavior is to not wrap
+        them, as if <literal>WITHOUT WRAPPER</literal> were specified. The
+        <literal>WITH WRAPPER</literal> clause is by default taken to mean
+        <literal>WITH UNCONDITIONAL WRAPPER</literal>, which means that even a
+        single result value will be wrapped. To apply the wrapper only when
+        multiple values are present, specify <literal>WITH CONDITIONAL WRAPPER</literal>.
+        Getting multiple values in result will be treated as an error if
+        <literal>WITHOUT WRAPPER</literal> is specified.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        If the result is a scalar string, by default, the returned value will
+        be surrounded by quotes, making it a valid JSON value.  It can be made
+        explicit by specifying <literal>KEEP QUOTES</literal>.  Conversely,
+        quotes can be omitted by specifying <literal>OMIT QUOTES</literal>.
+        To ensure that the result is a valid JSON value, <literal>OMIT QUOTES</literal>
+        cannot be specified when <literal>WITH WRAPPER</literal> is also
+        specified.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        The <literal>ON EMPTY</literal> clause specifies the behavior if
+        evaluating <replaceable>path_expression</replaceable> yields an empty
+        set. The <literal>ON ERROR</literal> clause specifies the behavior
+        if an error occurs when evaluating <replaceable>path_expression</replaceable>,
+        when coercing the result value to the <literal>RETURNING</literal> type,
+        or when evaluating the <literal>ON EMPTY</literal> expression if the
+        <replaceable>path_expression</replaceable> evaluation returns an empty
+        set.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        For both <literal>ON EMPTY</literal> and <literal>ON ERROR</literal>,
+        specifying <literal>ERROR</literal> will cause an error to be thrown with
+        the appropriate message. Other options include returning an SQL NULL, an
+        empty array (<literal>EMPTY <optional>ARRAY</optional></literal>),
+        an empty object (<literal>EMPTY OBJECT</literal>), or a user-specified
+        expression (<literal>DEFAULT</literal> <replaceable>expression</replaceable>)
+        that can be coerced to jsonb or the type specified in <literal>RETURNING</literal>.
+        The default when <literal>ON EMPTY</literal> or <literal>ON ERROR</literal>
+        is not specified is to return an SQL NULL value.
+       </para>
+      </listitem>
+     </itemizedlist>
+       <para>
+        Examples:
+       </para>
+       <para>
+        <literal>JSON_QUERY(jsonb '[1,[2,3],null]', 'lax $[*][$off]' PASSING 1 AS off WITH CONDITIONAL WRAPPER)</literal>
+        <returnvalue>3</returnvalue>
+       </para>
+       <para>
+        <literal>JSON_QUERY(jsonb '{"a": "[1, 2]"}', 'lax $.a' OMIT QUOTES)</literal>
+        <returnvalue>[1, 2]</returnvalue>
+       </para>
+       <para>
+        <literal>JSON_QUERY(jsonb '{"a": "[1, 2]"}', 'lax $.a' RETURNING int[] OMIT QUOTES ERROR ON ERROR)</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ERROR:  malformed array literal: "[1, 2]"
+DETAIL:  Missing "]" after array dimensions.
+</programlisting>
+       </para>
+      </entry>
+     </row>
+     <row>
+      <entry role="func_table_entry"><para role="func_signature">
+        <indexterm><primary>json_value</primary></indexterm>
+<synopsis>
+<function>JSON_VALUE</function> (
+<replaceable>context_item</replaceable>, <replaceable>path_expression</replaceable>
+<optional> <literal>PASSING</literal> { <replaceable>value</replaceable> <literal>AS</literal> <replaceable>varname</replaceable> } <optional>, ...</optional></optional>
+<optional> <literal>RETURNING</literal> <replaceable>data_type</replaceable> </optional>
+<optional> { <literal>ERROR</literal> | <literal>NULL</literal> | <literal>DEFAULT</literal> <replaceable>expression</replaceable> } <literal>ON EMPTY</literal> </optional>
+<optional> { <literal>ERROR</literal> | <literal>NULL</literal> | <literal>DEFAULT</literal> <replaceable>expression</replaceable> } <literal>ON ERROR</literal> </optional>) <returnvalue>text</returnvalue>
+</synopsis>
+       </para>
+     <itemizedlist>
+      <listitem>
+       <para>
+        Returns the result of applying the SQL/JSON
+        <replaceable>path_expression</replaceable> to the
+        <replaceable>context_item</replaceable>.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        Only use <function>JSON_VALUE()</function> if the extracted value is
+        expected to be a single <acronym>SQL/JSON</acronym> scalar item;
+        getting multiple values will be treated as an error. If you expect that
+        extracted value might be an object or an array, use the
+        <function>JSON_QUERY</function> function instead.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        By default, the result, which must be a single scalar value, is
+        returned as a value of type <type>text</type>, though the
+        <literal>RETURNING</literal> clause can be used to return as some
+        other type to which it can be successfully coerced.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        The <literal>ON ERROR</literal> and <literal>ON EMPTY</literal>
+        clauses have similar semantics as mentioned in the description of
+        <function>JSON_QUERY</function>, except the set of values returned in
+        lieu of throwing an error is different.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        Note that scalar strings returned by <function>JSON_VALUE</function>
+        always have their quotes removed, equivalent to specifying
+        <literal>OMIT QUOTES</literal> in <function>JSON_QUERY</function>.
+       </para>
+      </listitem>
+     </itemizedlist>
+       <para>
+        Examples:
+       </para>
+       <para>
+        <literal>JSON_VALUE(jsonb '"123.45"', '$' RETURNING float)</literal>
+        <returnvalue>123.45</returnvalue>
+       </para>
+       <para>
+        <literal>JSON_VALUE(jsonb '"03:04 2015-02-01"', '$.datetime("HH24:MI&nbsp;YYYY-MM-DD")' RETURNING date)</literal>
+        <returnvalue>2015-02-01</returnvalue>
+       </para>
+       <para>
+        <literal>JSON_VALUE(jsonb '[1,2]', 'strict $[$off]' PASSING 1 as off)</literal>
+        <returnvalue>2</returnvalue>
+       </para>
+       <para>
+        <literal>JSON_VALUE(jsonb '[1,2]', 'strict $[*]' DEFAULT 9 ON ERROR)</literal>
+        <returnvalue>9</returnvalue>
+       </para>
+      </entry>
+     </row>
+    </tbody>
+   </tgroup>
+  </table>
+  <note>
+   <para>
+    The <replaceable>context_item</replaceable> expression is converted to
+    <type>jsonb</type> by an implicit cast if the expression is not already of
+    type <type>jsonb</type>. Note, however, that any parsing errors that occur
+    during that conversion are thrown unconditionally, that is, are not
+    handled according to the (specified or implicit) <literal>ON ERROR</literal>
+    clause.
+   </para>
+  </note>
+  <note>
+   <para>
+    <function>JSON_VALUE()</function> returns an SQL NULL if
+    <replaceable>path_expression</replaceable> returns a JSON
+    <literal>null</literal>, whereas <function>JSON_QUERY()</function> returns
+    the JSON <literal>null</literal> as is.
+   </para>
+  </note>
+  </sect2>
+
+ <sect2 id="functions-sqljson-table">
+  <title>JSON_TABLE</title>
+  <indexterm>
+   <primary>json_table</primary>
+  </indexterm>
+
+  <para>
+   <function>JSON_TABLE</function> is an SQL/JSON function which
+   queries <acronym>JSON</acronym> data
+   and presents the results as a relational view, which can be accessed as a
+   regular SQL table. You can use <function>JSON_TABLE</function> inside
+   the <literal>FROM</literal> clause of a <literal>SELECT</literal>,
+   <literal>UPDATE</literal>, or <literal>DELETE</literal> and as data source
+   in a <literal>MERGE</literal> statement.
+  </para>
+
+  <para>
+   Taking JSON data as input, <function>JSON_TABLE</function> uses a JSON path
+   expression to extract a part of the provided data to use as a
+   <firstterm>row pattern</firstterm> for the constructed view.  Each SQL/JSON
+   value given by the row pattern serves as source for a separate row in the
+   constructed view.
+  </para>
+
+  <para>
+   To split the row pattern into columns, <function>JSON_TABLE</function>
+   provides the <literal>COLUMNS</literal> clause that defines the
+   schema of the created view. For each column, a separate JSON path expression
+   can be specified to be evaluated against the row pattern to get an SQL/JSON
+   value that will become the value for the specified column in a given output
+   row.
+  </para>
+
+  <para>
+   JSON data stored at a nested level of the row pattern can be extracted using
+   the <literal>NESTED PATH</literal> clause.  Each
+   <literal>NESTED PATH</literal> clause can be used to generate one or more
+   columns using the data from a nested level of the row pattern.  Those
+   columns can be specified using a <literal>COLUMNS</literal> clause that
+   looks similar to the top-level COLUMNS clause.  Rows constructed from
+   NESTED COLUMNS are called <firstterm>child rows</firstterm> and are joined
+   against the row constructed from the columns specified in the parent
+   <literal>COLUMNS</literal> clause to get the row in the final view.  Child
+   columns themselves may contain a <literal>NESTED PATH</literal>
+   specification thus allowing to extract data located at arbitrary nesting
+   levels.  Columns produced by multiple <literal>NESTED PATH</literal>s at the
+   same level are considered to be <firstterm>siblings</firstterm> of each
+   other and their rows after joining with the parent row are combined using
+   UNION.
+  </para>
+
+  <para>
+   The rows produced by <function>JSON_TABLE</function> are laterally
+   joined to the row that generated them, so you do not have to explicitly join
+   the constructed view with the original table holding <acronym>JSON</acronym>
+   data.
+  </para>
+
+  <para>
+   The syntax is:
+  </para>
+
+<synopsis>
+JSON_TABLE (
+    <replaceable>context_item</replaceable>, <replaceable>path_expression</replaceable> <optional> AS <replaceable>json_path_name</replaceable> </optional> <optional> PASSING { <replaceable>value</replaceable> AS <replaceable>varname</replaceable> } <optional>, ...</optional> </optional>
+    COLUMNS ( <replaceable class="parameter">json_table_column</replaceable> <optional>, ...</optional> )
+    <optional> { <literal>ERROR</literal> | <literal>EMPTY</literal> <optional>ARRAY</optional>} <literal>ON ERROR</literal> </optional>
+)
+
+<phrase>
+where <replaceable class="parameter">json_table_column</replaceable> is:
+</phrase>
+  <replaceable>name</replaceable> FOR ORDINALITY
+  | <replaceable>name</replaceable> <replaceable>type</replaceable>
+        <optional> FORMAT JSON <optional>ENCODING <literal>UTF8</literal></optional></optional>
+        <optional> PATH <replaceable>path_expression</replaceable> </optional>
+        <optional> { WITHOUT | WITH { CONDITIONAL | <optional>UNCONDITIONAL</optional> } } <optional> ARRAY </optional> WRAPPER </optional>
+        <optional> { KEEP | OMIT } QUOTES <optional> ON SCALAR STRING </optional> </optional>
+        <optional> { ERROR | NULL | EMPTY { <optional>ARRAY</optional> | OBJECT } | DEFAULT <replaceable>expression</replaceable> } ON EMPTY </optional>
+        <optional> { ERROR | NULL | EMPTY { <optional>ARRAY</optional> | OBJECT } | DEFAULT <replaceable>expression</replaceable> } ON ERROR </optional>
+  | <replaceable>name</replaceable> <replaceable>type</replaceable> EXISTS <optional> PATH <replaceable>path_expression</replaceable> </optional>
+        <optional> { ERROR | TRUE | FALSE | UNKNOWN } ON ERROR </optional>
+  | NESTED <optional> PATH </optional> <replaceable>path_expression</replaceable> <optional> AS <replaceable>json_path_name</replaceable> </optional> COLUMNS ( <replaceable>json_table_column</replaceable> <optional>, ...</optional> )
+</synopsis>
+
+  <para>
+   Each syntax element is described below in more detail.
+  </para>
+
+  <variablelist>
+   <varlistentry>
+    <term>
+     <literal><replaceable>context_item</replaceable>, <replaceable>path_expression</replaceable> <optional> <literal>AS</literal> <replaceable>json_path_name</replaceable> </optional> <optional> <literal>PASSING</literal> { <replaceable>value</replaceable> <literal>AS</literal> <replaceable>varname</replaceable> } <optional>, ...</optional></optional></literal>
+    </term>
+    <listitem>
+    <para>
+     The <replaceable>context_item</replaceable> specifies the input document
+     to query, the <replaceable>path_expression</replaceable> is an SQL/JSON
+     path expression defining the query, and <replaceable>json_path_name</replaceable>
+     is an optional name for the <replaceable>path_expression</replaceable>.
+     The optional <literal>PASSING</literal> clause provides data values for
+     the variables mentioned in the <replaceable>path_expression</replaceable>.
+     The result of the input data evaluation using the aforementioned elements
+     is called the <firstterm>row pattern</firstterm>, which is used as the
+     source for row values in the constructed view.
+    </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term>
+     <literal>COLUMNS</literal> ( <replaceable>json_table_column</replaceable> <optional>, ...</optional> )
+    </term>
+    <listitem>
+
+    <para>
+     The <literal>COLUMNS</literal> clause defining the schema of the
+     constructed view. In this clause, you can specify each column to be
+     filled with an SQL/JSON value obtained by applying a JSON path expression
+     against the row pattern.  <replaceable>json_table_column</replaceable> has
+     the following variants:
+    </para>
+
+  <variablelist>
+   <varlistentry>
+    <term>
+     <replaceable>name</replaceable> <literal>FOR ORDINALITY</literal>
+    </term>
+    <listitem>
+    <para>
+     Adds an ordinality column that provides sequential row numbering starting
+     from 1.  Each <literal>NESTED PATH</literal> (see below) gets its own
+     counter for any nested ordinality columns.
+    </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term>
+     <literal><replaceable>name</replaceable> <replaceable>type</replaceable>
+          <optional><literal>FORMAT JSON</literal> <optional>ENCODING <literal>UTF8</literal></optional></optional>
+          <optional> <literal>PATH</literal> <replaceable>path_expression</replaceable> </optional></literal>
+    </term>
+    <listitem>
+    <para>
+     Inserts an SQL/JSON value obtained by applying
+     <replaceable>path_expression</replaceable> against the row pattern into
+     the view's output row after coercing it to specified
+     <replaceable>type</replaceable>.
+    </para>
+    <para>
+     Specifying <literal>FORMAT JSON</literal> makes it explicit that you
+     expect the value to be a valid <type>json</type> object.  It only
+     makes sense to specify <literal>FORMAT JSON</literal> if
+     <replaceable>type</replaceable> is one of <type>bpchar</type>,
+     <type>bytea</type>, <type>character varying</type>, <type>name</type>,
+     <type>json</type>, <type>jsonb</type>, <type>text</type>, or a domain over
+     these types.
+    </para>
+    <para>
+     Optionally, you can specify <literal>WRAPPER</literal> and
+     <literal>QUOTES</literal> clauses to format the output. Note that
+     specifying <literal>OMIT QUOTES</literal> overrides
+     <literal>FORMAT JSON</literal> if also specified, because unquoted
+     literals do not constitute valid <type>json</type> values.
+    </para>
+    <para>
+     Optionally, you can use <literal>ON EMPTY</literal> and
+     <literal>ON ERROR</literal> clauses to specify whether to throw the error
+     or return the specified value when the result of JSON path evaluation is
+     empty and when an error occurs during JSON path evaluation or when
+     coercing the SQL/JSON value to the specified type, respectively.  The
+     default for both is to return a <literal>NULL</literal> value.
+    </para>
+    <note>
+     <para>
+      This clause is internally turned into and has the same semantics as
+      <function>JSON_VALUE</function> or <function>JSON_QUERY</function>.
+      The latter if the specified type is not a scalar type or if either of
+      <literal>FORMAT JSON</literal>, <literal>WRAPPER</literal>, or
+      <literal>QUOTES</literal> clause is present.
+     </para>
+    </note>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term>
+       <replaceable>name</replaceable> <replaceable>type</replaceable>
+       <literal>EXISTS</literal> <optional> <literal>PATH</literal> <replaceable>path_expression</replaceable> </optional>
+    </term>
+    <listitem>
+    <para>
+     Inserts a boolean value obtained by applying
+     <replaceable>path_expression</replaceable> against the row pattern
+     into the view's output row after coercing it to specified
+     <replaceable>type</replaceable>.
+    </para>
+    <para>
+     The value corresponds to whether applying the <literal>PATH</literal>
+     expression to the row pattern yields any values.
+    </para>
+    <para>
+     The specified <replaceable>type</replaceable> should have a cast from the
+     <type>boolean</type> type.
+    </para>
+    <para>
+     Optionally, you can use <literal>ON ERROR</literal> to specify whether to
+     throw the error or return the specified value when an error occurs during
+     JSON path evaluation or when coercing SQL/JSON value to the specified
+     type.  The default is to return a boolean value
+     <literal>FALSE</literal>.
+    </para>
+    <note>
+     <para>
+      This clause is internally turned into and has the same semantics as
+      <function>JSON_EXISTS</function>.
+     </para>
+    </note>
+      </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term>
+      <literal>NESTED <optional> PATH </optional></literal> <replaceable>path_expression</replaceable> <optional> <literal>AS</literal> <replaceable>json_path_name</replaceable> </optional>
+          <literal>COLUMNS</literal> ( <replaceable>json_table_column</replaceable> <optional>, ...</optional> )
+    </term>
+    <listitem>
+
+    <para>
+     Extracts SQL/JSON values from nested levels of the row pattern,
+     generates one or more columns as defined by the <literal>COLUMNS</literal>
+     subclause, and inserts the extracted SQL/JSON values into those
+     columns.  The <replaceable>json_table_column</replaceable>
+     expression in the <literal>COLUMNS</literal> subclause uses the same
+     syntax as in the parent <literal>COLUMNS</literal> clause.
+    </para>
+
+    <para>
+     The <literal>NESTED PATH</literal> syntax is recursive,
+     so you can go down multiple nested levels by specifying several
+     <literal>NESTED PATH</literal> subclauses within each other.
+     It allows to unnest the hierarchy of JSON objects and arrays
+     in a single function invocation rather than chaining several
+     <function>JSON_TABLE</function> expressions in an SQL statement.
+    </para>
+    </listitem>
+   </varlistentry>
+  </variablelist>
+
+   <note>
+     <para>
+      In each variant of <replaceable>json_table_column</replaceable> described
+      above, if the <literal>PATH</literal> clause is omitted, path expression
+      <literal>$.<replaceable>name</replaceable></literal> is used, where
+      <replaceable>name</replaceable> is the provided column name.
+     </para>
+    </note>
+
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term>
+     <literal>AS</literal> <replaceable>json_path_name</replaceable>
+    </term>
+    <listitem>
+
+    <para>
+     The optional <replaceable>json_path_name</replaceable> serves as an
+     identifier of the provided <replaceable>path_expression</replaceable>.
+     The name must be unique and distinct from the column names.
+    </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term>
+     { <literal>ERROR</literal> | <literal>EMPTY</literal> } <literal>ON ERROR</literal>
+    </term>
+    <listitem>
+
+    <para>
+     The optional <literal>ON ERROR</literal> can be used to specify how to
+     handle errors when evaluating the top-level
+     <replaceable>path_expression</replaceable>.  Use <literal>ERROR</literal>
+     if you want the errors to be thrown and <literal>EMPTY</literal> to
+     return an empty table, that is, a table containing 0 rows.  Note that
+     this clause does not affect the errors that occur when evaluating
+     columns, for which the behavior depends on whether the
+     <literal>ON ERROR</literal> clause is specified against a given column.
+    </para>
+    </listitem>
+   </varlistentry>
+  </variablelist>
+
+  <para>Examples</para>
+
+     <para>
+      In the examples that follow, the following table containing JSON data
+      will be used:
+
+<programlisting>
+CREATE TABLE my_films ( js jsonb );
+
+INSERT INTO my_films VALUES (
+'{ "favorites" : [
+   { "kind" : "comedy", "films" : [
+     { "title" : "Bananas",
+       "director" : "Woody Allen"},
+     { "title" : "The Dinner Game",
+       "director" : "Francis Veber" } ] },
+   { "kind" : "horror", "films" : [
+     { "title" : "Psycho",
+       "director" : "Alfred Hitchcock" } ] },
+   { "kind" : "thriller", "films" : [
+     { "title" : "Vertigo",
+       "director" : "Alfred Hitchcock" } ] },
+   { "kind" : "drama", "films" : [
+     { "title" : "Yojimbo",
+       "director" : "Akira Kurosawa" } ] }
+  ] }');
+</programlisting>
+
+     </para>
+     <para>
+      The following query shows how to use <function>JSON_TABLE</function> to
+      turn the JSON objects in the <structname>my_films</structname> table
+      to a view containing columns for the keys <literal>kind</literal>,
+      <literal>title</literal>, and <literal>director</literal> contained in
+      the original JSON along with an ordinality column:
+
+<programlisting>
+SELECT jt.* FROM
+ my_films,
+ JSON_TABLE (js, '$.favorites[*]' COLUMNS (
+   id FOR ORDINALITY,
+   kind text PATH '$.kind',
+   title text PATH '$.films[*].title' WITH WRAPPER,
+   director text PATH '$.films[*].director' WITH WRAPPER)) AS jt;
+</programlisting>
+
+<screen>
+ id |   kind   |             title              |             director
+----+----------+--------------------------------+----------------------------------
+  1 | comedy   | ["Bananas", "The Dinner Game"] | ["Woody Allen", "Francis Veber"]
+  2 | horror   | ["Psycho"]                     | ["Alfred Hitchcock"]
+  3 | thriller | ["Vertigo"]                    | ["Alfred Hitchcock"]
+  4 | drama    | ["Yojimbo"]                    | ["Akira Kurosawa"]
+(4 rows)
+</screen>
+
+     </para>
+     <para>
+      The following is a modified version of the above query to show the
+      usage of <literal>PASSING</literal> arguments in the filter specified in
+      the top-level JSON path expression and the various options for the
+      individual columns:
+
+<programlisting>
+SELECT jt.* FROM
+ my_films,
+ JSON_TABLE (js, '$.favorites[*] ? (@.films[*].director == $filter)'
+   PASSING 'Alfred Hitchcock' AS filter
+     COLUMNS (
+     id FOR ORDINALITY,
+     kind text PATH '$.kind',
+     title text FORMAT JSON PATH '$.films[*].title' OMIT QUOTES,
+     director text PATH '$.films[*].director' KEEP QUOTES)) AS jt;
+</programlisting>
+
+<screen>
+ id |   kind   |  title  |      director
+----+----------+---------+--------------------
+  1 | horror   | Psycho  | "Alfred Hitchcock"
+  2 | thriller | Vertigo | "Alfred Hitchcock"
+(2 rows)
+</screen>
+
+     </para>
+     <para>
+      The following is a modified version of the above query to show the usage
+      of <literal>NESTED PATH</literal> for populating title and director
+      columns, illustrating how they are joined to the parent columns id and
+      kind:
+
+<programlisting>
+SELECT jt.* FROM
+ my_films,
+ JSON_TABLE ( js, '$.favorites[*] ? (@.films[*].director == $filter)'
+   PASSING 'Alfred Hitchcock' AS filter
+   COLUMNS (
+    id FOR ORDINALITY,
+    kind text PATH '$.kind',
+    NESTED PATH '$.films[*]' COLUMNS (
+      title text FORMAT JSON PATH '$.title' OMIT QUOTES,
+      director text PATH '$.director' KEEP QUOTES))) AS jt;
+</programlisting>
+
+<screen>
+ id |   kind   |  title  |      director
+----+----------+---------+--------------------
+  1 | horror   | Psycho  | "Alfred Hitchcock"
+  2 | thriller | Vertigo | "Alfred Hitchcock"
+(2 rows)
+</screen>
+
+     </para>
+
+     <para>
+      The following is the same query but without the filter in the root
+      path:
+
+<programlisting>
+SELECT jt.* FROM
+ my_films,
+ JSON_TABLE ( js, '$.favorites[*]'
+   COLUMNS (
+    id FOR ORDINALITY,
+    kind text PATH '$.kind',
+    NESTED PATH '$.films[*]' COLUMNS (
+      title text FORMAT JSON PATH '$.title' OMIT QUOTES,
+      director text PATH '$.director' KEEP QUOTES))) AS jt;
+</programlisting>
+
+<screen>
+ id |   kind   |      title      |      director
+----+----------+-----------------+--------------------
+  1 | comedy   | Bananas         | "Woody Allen"
+  1 | comedy   | The Dinner Game | "Francis Veber"
+  2 | horror   | Psycho          | "Alfred Hitchcock"
+  3 | thriller | Vertigo         | "Alfred Hitchcock"
+  4 | drama    | Yojimbo         | "Akira Kurosawa"
+(5 rows)
+</screen>
+
+     </para>
+
+     <para>
+      The following shows another query using a different <type>JSON</type>
+      object as input.  It shows the UNION "sibling join" between
+      <literal>NESTED</literal> paths <literal>$.movies[*]</literal> and
+      <literal>$.books[*]</literal> and also the usage of
+      <literal>FOR ORDINALITY</literal> column at <literal>NESTED</literal>
+      levels (columns <literal>movie_id</literal>, <literal>book_id</literal>,
+      and <literal>author_id</literal>):
+
+<programlisting>
+SELECT * FROM JSON_TABLE (
+'{"favorites":
+    [{"movies":
+      [{"name": "One", "director": "John Doe"},
+       {"name": "Two", "director": "Don Joe"}],
+     "books":
+      [{"name": "Mystery", "authors": [{"name": "Brown Dan"}]},
+       {"name": "Wonder", "authors": [{"name": "Jun Murakami"}, {"name":"Craig Doe"}]}]
+}]}'::json, '$.favorites[*]'
+COLUMNS (
+  user_id FOR ORDINALITY,
+  NESTED '$.movies[*]'
+    COLUMNS (
+    movie_id FOR ORDINALITY,
+    mname text PATH '$.name',
+    director text),
+  NESTED '$.books[*]'
+    COLUMNS (
+      book_id FOR ORDINALITY,
+      bname text PATH '$.name',
+      NESTED '$.authors[*]'
+        COLUMNS (
+          author_id FOR ORDINALITY,
+          author_name text PATH '$.name'))));
+</programlisting>
+
+<screen>
+ user_id | movie_id | mname | director | book_id |  bname  | author_id | author_name
+---------+----------+-------+----------+---------+---------+-----------+--------------
+       1 |        1 | One   | John Doe |         |         |           |
+       1 |        2 | Two   | Don Joe  |         |         |           |
+       1 |          |       |          |       1 | Mystery |         1 | Brown Dan
+       1 |          |       |          |       2 | Wonder  |         1 | Jun Murakami
+       1 |          |       |          |       2 | Wonder  |         2 | Craig Doe
+(5 rows)
+</screen>
+
+     </para>
+  </sect2>
+ </sect1>
diff --git a/doc/src/sgml/func/func-logical.sgml b/doc/src/sgml/func/func-logical.sgml
new file mode 100644
index 0000000000000..65e50e65a8117
--- /dev/null
+++ b/doc/src/sgml/func/func-logical.sgml
@@ -0,0 +1,146 @@
+  <sect1 id="functions-logical">
+   <title>Logical Operators</title>
+
+   <indexterm zone="functions-logical">
+    <primary>operator</primary>
+    <secondary>logical</secondary>
+   </indexterm>
+
+   <indexterm>
+    <primary>Boolean</primary>
+    <secondary>operators</secondary>
+    <see>operators, logical</see>
+   </indexterm>
+
+   <para>
+    The usual logical operators are available:
+
+    <indexterm>
+     <primary>AND (operator)</primary>
+    </indexterm>
+
+    <indexterm>
+     <primary>OR (operator)</primary>
+    </indexterm>
+
+    <indexterm>
+     <primary>NOT (operator)</primary>
+    </indexterm>
+
+    <indexterm>
+     <primary>conjunction</primary>
+    </indexterm>
+
+    <indexterm>
+     <primary>disjunction</primary>
+    </indexterm>
+
+    <indexterm>
+     <primary>negation</primary>
+    </indexterm>
+
+<synopsis>
+<type>boolean</type> <literal>AND</literal> <type>boolean</type> <returnvalue>boolean</returnvalue>
+<type>boolean</type> <literal>OR</literal> <type>boolean</type> <returnvalue>boolean</returnvalue>
+<literal>NOT</literal> <type>boolean</type> <returnvalue>boolean</returnvalue>
+</synopsis>
+
+    <acronym>SQL</acronym> uses a three-valued logic system with true,
+    false, and <literal>null</literal>, which represents <quote>unknown</quote>.
+    Observe the following truth tables:
+
+    <informaltable>
+     <tgroup cols="4">
+      <thead>
+       <row>
+        <entry><replaceable>a</replaceable></entry>
+        <entry><replaceable>b</replaceable></entry>
+        <entry><replaceable>a</replaceable> AND <replaceable>b</replaceable></entry>
+        <entry><replaceable>a</replaceable> OR <replaceable>b</replaceable></entry>
+       </row>
+      </thead>
+
+      <tbody>
+       <row>
+        <entry>TRUE</entry>
+        <entry>TRUE</entry>
+        <entry>TRUE</entry>
+        <entry>TRUE</entry>
+       </row>
+
+       <row>
+        <entry>TRUE</entry>
+        <entry>FALSE</entry>
+        <entry>FALSE</entry>
+        <entry>TRUE</entry>
+       </row>
+
+       <row>
+        <entry>TRUE</entry>
+        <entry>NULL</entry>
+        <entry>NULL</entry>
+        <entry>TRUE</entry>
+       </row>
+
+       <row>
+        <entry>FALSE</entry>
+        <entry>FALSE</entry>
+        <entry>FALSE</entry>
+        <entry>FALSE</entry>
+       </row>
+
+       <row>
+        <entry>FALSE</entry>
+        <entry>NULL</entry>
+        <entry>FALSE</entry>
+        <entry>NULL</entry>
+       </row>
+
+       <row>
+        <entry>NULL</entry>
+        <entry>NULL</entry>
+        <entry>NULL</entry>
+        <entry>NULL</entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </informaltable>
+
+    <informaltable>
+     <tgroup cols="2">
+      <thead>
+       <row>
+        <entry><replaceable>a</replaceable></entry>
+        <entry>NOT <replaceable>a</replaceable></entry>
+       </row>
+      </thead>
+
+      <tbody>
+       <row>
+        <entry>TRUE</entry>
+        <entry>FALSE</entry>
+       </row>
+
+       <row>
+        <entry>FALSE</entry>
+        <entry>TRUE</entry>
+       </row>
+
+       <row>
+        <entry>NULL</entry>
+        <entry>NULL</entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </informaltable>
+   </para>
+
+   <para>
+    The operators <literal>AND</literal> and <literal>OR</literal> are
+    commutative, that is, you can switch the left and right operands
+    without affecting the result.  (However, it is not guaranteed that
+    the left operand is evaluated before the right operand.  See <xref
+    linkend="syntax-express-eval"/> for more information about the
+    order of evaluation of subexpressions.)
+   </para>
+  </sect1>
diff --git a/doc/src/sgml/func/func-matching.sgml b/doc/src/sgml/func/func-matching.sgml
new file mode 100644
index 0000000000000..7d44e2a27bcca
--- /dev/null
+++ b/doc/src/sgml/func/func-matching.sgml
@@ -0,0 +1,2471 @@
+ <sect1 id="functions-matching">
+  <title>Pattern Matching</title>
+
+  <indexterm zone="functions-matching">
+   <primary>pattern matching</primary>
+  </indexterm>
+
+   <para>
+    There are three separate approaches to pattern matching provided
+    by <productname>PostgreSQL</productname>: the traditional
+    <acronym>SQL</acronym> <function>LIKE</function> operator, the
+    more recent <function>SIMILAR TO</function> operator (added in
+    SQL:1999), and <acronym>POSIX</acronym>-style regular
+    expressions.  Aside from the basic <quote>does this string match
+    this pattern?</quote> operators, functions are available to extract
+    or replace matching substrings and to split a string at matching
+    locations.
+   </para>
+
+   <tip>
+    <para>
+     If you have pattern matching needs that go beyond this,
+     consider writing a user-defined function in Perl or Tcl.
+    </para>
+   </tip>
+
+   <caution>
+    <para>
+     While most regular-expression searches can be executed very quickly,
+     regular expressions can be contrived that take arbitrary amounts of
+     time and memory to process.  Be wary of accepting regular-expression
+     search patterns from hostile sources.  If you must do so, it is
+     advisable to impose a statement timeout.
+    </para>
+
+    <para>
+     Searches using <function>SIMILAR TO</function> patterns have the same
+     security hazards, since <function>SIMILAR TO</function> provides many
+     of the same capabilities as <acronym>POSIX</acronym>-style regular
+     expressions.
+    </para>
+
+    <para>
+     <function>LIKE</function> searches, being much simpler than the other
+     two options, are safer to use with possibly-hostile pattern sources.
+    </para>
+   </caution>
+
+   <para>
+    <function>SIMILAR TO</function> and <acronym>POSIX</acronym>-style regular
+    expressions do not support nondeterministic collations.  If required, use
+    <function>LIKE</function> or apply a different collation to the expression
+    to work around this limitation.
+   </para>
+
+  <sect2 id="functions-like">
+   <title><function>LIKE</function></title>
+
+   <indexterm>
+    <primary>LIKE</primary>
+   </indexterm>
+
+<synopsis>
+<replaceable>string</replaceable> LIKE <replaceable>pattern</replaceable> <optional>ESCAPE <replaceable>escape-character</replaceable></optional>
+<replaceable>string</replaceable> NOT LIKE <replaceable>pattern</replaceable> <optional>ESCAPE <replaceable>escape-character</replaceable></optional>
+</synopsis>
+
+    <para>
+     The <function>LIKE</function> expression returns true if the
+     <replaceable>string</replaceable> matches the supplied
+     <replaceable>pattern</replaceable>.  (As
+     expected, the <function>NOT LIKE</function> expression returns
+     false if <function>LIKE</function> returns true, and vice versa.
+     An equivalent expression is
+     <literal>NOT (<replaceable>string</replaceable> LIKE
+      <replaceable>pattern</replaceable>)</literal>.)
+    </para>
+
+    <para>
+     If <replaceable>pattern</replaceable> does not contain percent
+     signs or underscores, then the pattern only represents the string
+     itself; in that case <function>LIKE</function> acts like the
+     equals operator.  An underscore (<literal>_</literal>) in
+     <replaceable>pattern</replaceable> stands for (matches) any single
+     character; a percent sign (<literal>%</literal>) matches any sequence
+     of zero or more characters.
+    </para>
+
+   <para>
+    Some examples:
+<programlisting>
+'abc' LIKE 'abc'    <lineannotation>true</lineannotation>
+'abc' LIKE 'a%'     <lineannotation>true</lineannotation>
+'abc' LIKE '_b_'    <lineannotation>true</lineannotation>
+'abc' LIKE 'c'      <lineannotation>false</lineannotation>
+</programlisting>
+   </para>
+
+   <para>
+    <function>LIKE</function> pattern matching supports nondeterministic
+    collations (see <xref linkend="collation-nondeterministic"/>), such as
+    case-insensitive collations or collations that, say, ignore punctuation.
+    So with a case-insensitive collation, one could have:
+<programlisting>
+'AbC' LIKE 'abc' COLLATE case_insensitive    <lineannotation>true</lineannotation>
+'AbC' LIKE 'a%' COLLATE case_insensitive     <lineannotation>true</lineannotation>
+</programlisting>
+    With collations that ignore certain characters or in general that consider
+    strings of different lengths equal, the semantics can become a bit more
+    complicated.  Consider these examples:
+<programlisting>
+'.foo.' LIKE 'foo' COLLATE ign_punct    <lineannotation>true</lineannotation>
+'.foo.' LIKE 'f_o' COLLATE ign_punct    <lineannotation>true</lineannotation>
+'.foo.' LIKE '_oo' COLLATE ign_punct    <lineannotation>false</lineannotation>
+</programlisting>
+    The way the matching works is that the pattern is partitioned into
+    sequences of wildcards and non-wildcard strings (wildcards being
+    <literal>_</literal> and <literal>%</literal>).  For example, the pattern
+    <literal>f_o</literal> is partitioned into <literal>f, _, o</literal>, the
+    pattern <literal>_oo</literal> is partitioned into <literal>_,
+    oo</literal>.  The input string matches the pattern if it can be
+    partitioned in such a way that the wildcards match one character or any
+    number of characters respectively and the non-wildcard partitions are
+    equal under the applicable collation.  So for example, <literal>'.foo.'
+    LIKE 'f_o' COLLATE ign_punct</literal> is true because one can partition
+    <literal>.foo.</literal> into <literal>.f, o, o.</literal>, and then
+    <literal>'.f' = 'f' COLLATE ign_punct</literal>, <literal>'o'</literal>
+    matches the <literal>_</literal> wildcard, and <literal>'o.' = 'o' COLLATE
+    ign_punct</literal>.  But <literal>'.foo.' LIKE '_oo' COLLATE
+    ign_punct</literal> is false because <literal>.foo.</literal> cannot be
+    partitioned in a way that the first character is any character and the
+    rest of the string compares equal to <literal>oo</literal>.  (Note that
+    the single-character wildcard always matches exactly one character,
+    independent of the collation.  So in this example, the
+    <literal>_</literal> would match <literal>.</literal>, but then the rest
+    of the input string won't match the rest of the pattern.)
+   </para>
+
+   <para>
+    <function>LIKE</function> pattern matching always covers the entire
+    string.  Therefore, if it's desired to match a sequence anywhere within
+    a string, the pattern must start and end with a percent sign.
+   </para>
+
+   <para>
+    To match a literal underscore or percent sign without matching
+    other characters, the respective character in
+    <replaceable>pattern</replaceable> must be
+    preceded by the escape character.  The default escape
+    character is the backslash but a different one can be selected by
+    using the <literal>ESCAPE</literal> clause.  To match the escape
+    character itself, write two escape characters.
+   </para>
+
+   <note>
+    <para>
+     If you have <xref linkend="guc-standard-conforming-strings"/> turned off,
+     any backslashes you write in literal string constants will need to be
+     doubled.  See <xref linkend="sql-syntax-strings"/> for more information.
+    </para>
+   </note>
+
+   <para>
+    It's also possible to select no escape character by writing
+    <literal>ESCAPE ''</literal>.  This effectively disables the
+    escape mechanism, which makes it impossible to turn off the
+    special meaning of underscore and percent signs in the pattern.
+   </para>
+
+   <para>
+    According to the SQL standard, omitting <literal>ESCAPE</literal>
+    means there is no escape character (rather than defaulting to a
+    backslash), and a zero-length <literal>ESCAPE</literal> value is
+    disallowed.  <productname>PostgreSQL</productname>'s behavior in
+    this regard is therefore slightly nonstandard.
+   </para>
+
+   <para>
+    The key word <token>ILIKE</token> can be used instead of
+    <token>LIKE</token> to make the match case-insensitive according to the
+    active locale.  (But this does not support nondeterministic collations.)
+    This is not in the <acronym>SQL</acronym> standard but is a
+    <productname>PostgreSQL</productname> extension.
+   </para>
+
+   <para>
+    The operator <literal>~~</literal> is equivalent to
+    <function>LIKE</function>, and <literal>~~*</literal> corresponds to
+    <function>ILIKE</function>.  There are also
+    <literal>!~~</literal> and <literal>!~~*</literal> operators that
+    represent <function>NOT LIKE</function> and <function>NOT
+    ILIKE</function>, respectively.  All of these operators are
+    <productname>PostgreSQL</productname>-specific.  You may see these
+    operator names in <command>EXPLAIN</command> output and similar
+    places, since the parser actually translates <function>LIKE</function>
+    et al. to these operators.
+   </para>
+
+   <para>
+    The phrases <function>LIKE</function>, <function>ILIKE</function>,
+    <function>NOT LIKE</function>, and <function>NOT ILIKE</function> are
+    generally treated as operators
+    in <productname>PostgreSQL</productname> syntax; for example they can
+    be used in <replaceable>expression</replaceable>
+    <replaceable>operator</replaceable> ANY
+    (<replaceable>subquery</replaceable>) constructs, although
+    an <literal>ESCAPE</literal> clause cannot be included there.  In some
+    obscure cases it may be necessary to use the underlying operator names
+    instead.
+   </para>
+
+   <para>
+    Also see the starts-with operator <literal>^@</literal> and the
+    corresponding <function>starts_with()</function> function, which are
+    useful in cases where simply matching the beginning of a string is
+    needed.
+   </para>
+  </sect2>
+
+
+  <sect2 id="functions-similarto-regexp">
+   <title><function>SIMILAR TO</function> Regular Expressions</title>
+
+   <indexterm>
+    <primary>regular expression</primary>
+    <!-- <seealso>pattern matching</seealso> breaks index build -->
+   </indexterm>
+
+   <indexterm>
+    <primary>SIMILAR TO</primary>
+   </indexterm>
+   <indexterm>
+    <primary>substring</primary>
+   </indexterm>
+
+<synopsis>
+<replaceable>string</replaceable> SIMILAR TO <replaceable>pattern</replaceable> <optional>ESCAPE <replaceable>escape-character</replaceable></optional>
+<replaceable>string</replaceable> NOT SIMILAR TO <replaceable>pattern</replaceable> <optional>ESCAPE <replaceable>escape-character</replaceable></optional>
+</synopsis>
+
+   <para>
+    The <function>SIMILAR TO</function> operator returns true or
+    false depending on whether its pattern matches the given string.
+    It is similar to <function>LIKE</function>, except that it
+    interprets the pattern using the SQL standard's definition of a
+    regular expression.  SQL regular expressions are a curious cross
+    between <function>LIKE</function> notation and common (POSIX) regular
+    expression notation.
+   </para>
+
+   <para>
+    Like <function>LIKE</function>, the <function>SIMILAR TO</function>
+    operator succeeds only if its pattern matches the entire string;
+    this is unlike common regular expression behavior where the pattern
+    can match any part of the string.
+    Also like
+    <function>LIKE</function>, <function>SIMILAR TO</function> uses
+    <literal>_</literal> and <literal>%</literal> as wildcard characters denoting
+    any single character and any string, respectively (these are
+    comparable to <literal>.</literal> and <literal>.*</literal> in POSIX regular
+    expressions).
+   </para>
+
+   <para>
+    In addition to these facilities borrowed from <function>LIKE</function>,
+    <function>SIMILAR TO</function> supports these pattern-matching
+    metacharacters borrowed from POSIX regular expressions:
+
+   <itemizedlist>
+    <listitem>
+     <para>
+      <literal>|</literal> denotes alternation (either of two alternatives).
+     </para>
+    </listitem>
+    <listitem>
+     <para>
+      <literal>*</literal> denotes repetition of the previous item zero
+      or more times.
+     </para>
+    </listitem>
+    <listitem>
+     <para>
+      <literal>+</literal> denotes repetition of the previous item one
+      or more times.
+     </para>
+    </listitem>
+    <listitem>
+     <para>
+      <literal>?</literal> denotes repetition of the previous item zero
+      or one time.
+     </para>
+    </listitem>
+    <listitem>
+     <para>
+      <literal>{</literal><replaceable>m</replaceable><literal>}</literal> denotes repetition
+      of the previous item exactly <replaceable>m</replaceable> times.
+     </para>
+    </listitem>
+    <listitem>
+     <para>
+      <literal>{</literal><replaceable>m</replaceable><literal>,}</literal> denotes repetition
+      of the previous item <replaceable>m</replaceable> or more times.
+     </para>
+    </listitem>
+    <listitem>
+     <para>
+      <literal>{</literal><replaceable>m</replaceable><literal>,</literal><replaceable>n</replaceable><literal>}</literal>
+      denotes repetition of the previous item at least <replaceable>m</replaceable> and
+      not more than <replaceable>n</replaceable> times.
+     </para>
+    </listitem>
+    <listitem>
+     <para>
+      Parentheses <literal>()</literal> can be used to group items into
+      a single logical item.
+     </para>
+    </listitem>
+    <listitem>
+     <para>
+      A bracket expression <literal>[...]</literal> specifies a character
+      class, just as in POSIX regular expressions.
+     </para>
+    </listitem>
+   </itemizedlist>
+
+    Notice that the period (<literal>.</literal>) is not a metacharacter
+    for <function>SIMILAR TO</function>.
+   </para>
+
+   <para>
+    As with <function>LIKE</function>, a backslash disables the special
+    meaning of any of these metacharacters.  A different escape character
+    can be specified with <literal>ESCAPE</literal>, or the escape
+    capability can be disabled by writing <literal>ESCAPE ''</literal>.
+   </para>
+
+   <para>
+    According to the SQL standard, omitting <literal>ESCAPE</literal>
+    means there is no escape character (rather than defaulting to a
+    backslash), and a zero-length <literal>ESCAPE</literal> value is
+    disallowed.  <productname>PostgreSQL</productname>'s behavior in
+    this regard is therefore slightly nonstandard.
+   </para>
+
+   <para>
+    Another nonstandard extension is that following the escape character
+    with a letter or digit provides access to the escape sequences
+    defined for POSIX regular expressions; see
+    <xref linkend="posix-character-entry-escapes-table"/>,
+    <xref linkend="posix-class-shorthand-escapes-table"/>, and
+    <xref linkend="posix-constraint-escapes-table"/> below.
+   </para>
+
+   <para>
+    Some examples:
+<programlisting>
+'abc' SIMILAR TO 'abc'          <lineannotation>true</lineannotation>
+'abc' SIMILAR TO 'a'            <lineannotation>false</lineannotation>
+'abc' SIMILAR TO '%(b|d)%'      <lineannotation>true</lineannotation>
+'abc' SIMILAR TO '(b|c)%'       <lineannotation>false</lineannotation>
+'-abc-' SIMILAR TO '%\mabc\M%'  <lineannotation>true</lineannotation>
+'xabcy' SIMILAR TO '%\mabc\M%'  <lineannotation>false</lineannotation>
+</programlisting>
+   </para>
+
+   <para>
+    The <function>substring</function> function with three parameters
+    provides extraction of a substring that matches an SQL
+    regular expression pattern.  The function can be written according
+    to standard SQL syntax:
+<synopsis>
+substring(<replaceable>string</replaceable> similar <replaceable>pattern</replaceable> escape <replaceable>escape-character</replaceable>)
+</synopsis>
+    or using the now obsolete SQL:1999 syntax:
+<synopsis>
+substring(<replaceable>string</replaceable> from <replaceable>pattern</replaceable> for <replaceable>escape-character</replaceable>)
+</synopsis>
+    or as a plain three-argument function:
+<synopsis>
+substring(<replaceable>string</replaceable>, <replaceable>pattern</replaceable>, <replaceable>escape-character</replaceable>)
+</synopsis>
+    As with <literal>SIMILAR TO</literal>, the
+    specified pattern must match the entire data string, or else the
+    function fails and returns null.  To indicate the part of the
+    pattern for which the matching data sub-string is of interest,
+    the pattern should contain
+    two occurrences of the escape character followed by a double quote
+    (<literal>"</literal>). <!-- " font-lock sanity -->
+    The text matching the portion of the pattern
+    between these separators is returned when the match is successful.
+   </para>
+
+   <para>
+    The escape-double-quote separators actually
+    divide <function>substring</function>'s pattern into three independent
+    regular expressions; for example, a vertical bar (<literal>|</literal>)
+    in any of the three sections affects only that section.  Also, the first
+    and third of these regular expressions are defined to match the smallest
+    possible amount of text, not the largest, when there is any ambiguity
+    about how much of the data string matches which pattern.  (In POSIX
+    parlance, the first and third regular expressions are forced to be
+    non-greedy.)
+   </para>
+
+   <para>
+    As an extension to the SQL standard, <productname>PostgreSQL</productname>
+    allows there to be just one escape-double-quote separator, in which case
+    the third regular expression is taken as empty; or no separators, in which
+    case the first and third regular expressions are taken as empty.
+   </para>
+
+   <para>
+    Some examples, with <literal>#&quot;</literal> delimiting the return string:
+<programlisting>
+substring('foobar' similar '%#"o_b#"%' escape '#')   <lineannotation>oob</lineannotation>
+substring('foobar' similar '#"o_b#"%' escape '#')    <lineannotation>NULL</lineannotation>
+</programlisting>
+   </para>
+  </sect2>
+
+  <sect2 id="functions-posix-regexp">
+   <title><acronym>POSIX</acronym> Regular Expressions</title>
+
+   <indexterm zone="functions-posix-regexp">
+    <primary>regular expression</primary>
+    <seealso>pattern matching</seealso>
+   </indexterm>
+   <indexterm>
+    <primary>substring</primary>
+   </indexterm>
+   <indexterm>
+    <primary>regexp_count</primary>
+   </indexterm>
+   <indexterm>
+    <primary>regexp_instr</primary>
+   </indexterm>
+   <indexterm>
+    <primary>regexp_like</primary>
+   </indexterm>
+   <indexterm>
+    <primary>regexp_match</primary>
+   </indexterm>
+   <indexterm>
+    <primary>regexp_matches</primary>
+   </indexterm>
+   <indexterm>
+    <primary>regexp_replace</primary>
+   </indexterm>
+   <indexterm>
+    <primary>regexp_split_to_table</primary>
+   </indexterm>
+   <indexterm>
+    <primary>regexp_split_to_array</primary>
+   </indexterm>
+   <indexterm>
+    <primary>regexp_substr</primary>
+   </indexterm>
+
+   <para>
+    <xref linkend="functions-posix-table"/> lists the available
+    operators for pattern matching using POSIX regular expressions.
+   </para>
+
+   <table id="functions-posix-table">
+    <title>Regular Expression Match Operators</title>
+
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Operator
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+      <tbody>
+       <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>text</type> <literal>~</literal> <type>text</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        String matches regular expression, case sensitively
+       </para>
+       <para>
+        <literal>'thomas' ~ 't.*ma'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+       </row>
+
+       <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>text</type> <literal>~*</literal> <type>text</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        String matches regular expression, case-insensitively
+       </para>
+       <para>
+        <literal>'thomas' ~* 'T.*ma'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+       </row>
+
+       <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>text</type> <literal>!~</literal> <type>text</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        String does not match regular expression, case sensitively
+       </para>
+       <para>
+        <literal>'thomas' !~ 't.*max'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+       </row>
+
+       <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>text</type> <literal>!~*</literal> <type>text</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        String does not match regular expression, case-insensitively
+       </para>
+       <para>
+        <literal>'thomas' !~* 'T.*ma'</literal>
+        <returnvalue>f</returnvalue>
+       </para></entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+    <para>
+     <acronym>POSIX</acronym> regular expressions provide a more
+     powerful means for pattern matching than the <function>LIKE</function> and
+     <function>SIMILAR TO</function> operators.
+     Many Unix tools such as <command>egrep</command>,
+     <command>sed</command>, or <command>awk</command> use a pattern
+     matching language that is similar to the one described here.
+    </para>
+
+    <para>
+     A regular expression is a character sequence that is an
+     abbreviated definition of a set of strings (a <firstterm>regular
+     set</firstterm>).  A string is said to match a regular expression
+     if it is a member of the regular set described by the regular
+     expression.  As with <function>LIKE</function>, pattern characters
+     match string characters exactly unless they are special characters
+     in the regular expression language &mdash; but regular expressions use
+     different special characters than <function>LIKE</function> does.
+     Unlike <function>LIKE</function> patterns, a
+     regular expression is allowed to match anywhere within a string, unless
+     the regular expression is explicitly anchored to the beginning or
+     end of the string.
+    </para>
+
+    <para>
+     Some examples:
+<programlisting>
+'abcd' ~ 'bc'     <lineannotation>true</lineannotation>
+'abcd' ~ 'a.c'    <lineannotation>true &mdash; dot matches any character</lineannotation>
+'abcd' ~ 'a.*d'   <lineannotation>true &mdash; <literal>*</literal> repeats the preceding pattern item</lineannotation>
+'abcd' ~ '(b|x)'  <lineannotation>true &mdash; <literal>|</literal> means OR, parentheses group</lineannotation>
+'abcd' ~ '^a'     <lineannotation>true &mdash; <literal>^</literal> anchors to start of string</lineannotation>
+'abcd' ~ '^(b|c)' <lineannotation>false &mdash; would match except for anchoring</lineannotation>
+</programlisting>
+    </para>
+
+    <para>
+     The <acronym>POSIX</acronym> pattern language is described in much
+     greater detail below.
+    </para>
+
+    <para>
+     The <function>substring</function> function with two parameters,
+     <function>substring(<replaceable>string</replaceable> from
+     <replaceable>pattern</replaceable>)</function>, provides extraction of a
+     substring
+     that matches a POSIX regular expression pattern.  It returns null if
+     there is no match, otherwise the first portion of the text that matched the
+     pattern.  But if the pattern contains any parentheses, the portion
+     of the text that matched the first parenthesized subexpression (the
+     one whose left parenthesis comes first) is
+     returned.  You can put parentheses around the whole expression
+     if you want to use parentheses within it without triggering this
+     exception.  If you need parentheses in the pattern before the
+     subexpression you want to extract, see the non-capturing parentheses
+     described below.
+    </para>
+
+   <para>
+    Some examples:
+<programlisting>
+substring('foobar' from 'o.b')     <lineannotation>oob</lineannotation>
+substring('foobar' from 'o(.)b')   <lineannotation>o</lineannotation>
+</programlisting>
+   </para>
+
+    <para>
+     The <function>regexp_count</function> function counts the number of
+     places where a POSIX regular expression pattern matches a string.
+     It has the syntax
+     <function>regexp_count</function>(<replaceable>string</replaceable>,
+     <replaceable>pattern</replaceable>
+     <optional>, <replaceable>start</replaceable>
+     <optional>, <replaceable>flags</replaceable>
+     </optional></optional>).
+     <replaceable>pattern</replaceable> is searched for
+     in <replaceable>string</replaceable>, normally from the beginning of
+     the string, but if the <replaceable>start</replaceable> parameter is
+     provided then beginning from that character index.
+     The <replaceable>flags</replaceable> parameter is an optional text
+     string containing zero or more single-letter flags that change the
+     function's behavior.  For example, including <literal>i</literal> in
+     <replaceable>flags</replaceable> specifies case-insensitive matching.
+     Supported flags are described in
+     <xref linkend="posix-embedded-options-table"/>.
+    </para>
+
+    <para>
+     Some examples:
+<programlisting>
+regexp_count('ABCABCAXYaxy', 'A.')          <lineannotation>3</lineannotation>
+regexp_count('ABCABCAXYaxy', 'A.', 1, 'i')  <lineannotation>4</lineannotation>
+</programlisting>
+    </para>
+
+    <para>
+     The <function>regexp_instr</function> function returns the starting or
+     ending position of the <replaceable>N</replaceable>'th match of a
+     POSIX regular expression pattern to a string, or zero if there is no
+     such match.  It has the syntax
+     <function>regexp_instr</function>(<replaceable>string</replaceable>,
+     <replaceable>pattern</replaceable>
+     <optional>, <replaceable>start</replaceable>
+     <optional>, <replaceable>N</replaceable>
+     <optional>, <replaceable>endoption</replaceable>
+     <optional>, <replaceable>flags</replaceable>
+     <optional>, <replaceable>subexpr</replaceable>
+     </optional></optional></optional></optional></optional>).
+     <replaceable>pattern</replaceable> is searched for
+     in <replaceable>string</replaceable>, normally from the beginning of
+     the string, but if the <replaceable>start</replaceable> parameter is
+     provided then beginning from that character index.
+     If <replaceable>N</replaceable> is specified
+     then the <replaceable>N</replaceable>'th match of the pattern
+     is located, otherwise the first match is located.
+     If the <replaceable>endoption</replaceable> parameter is omitted or
+     specified as zero, the function returns the position of the first
+     character of the match.  Otherwise, <replaceable>endoption</replaceable>
+     must be one, and the function returns the position of the character
+     following the match.
+     The <replaceable>flags</replaceable> parameter is an optional text
+     string containing zero or more single-letter flags that change the
+     function's behavior.  Supported flags are described
+     in <xref linkend="posix-embedded-options-table"/>.
+     For a pattern containing parenthesized
+     subexpressions, <replaceable>subexpr</replaceable> is an integer
+     indicating which subexpression is of interest: the result identifies
+     the position of the substring matching that subexpression.
+     Subexpressions are numbered in the order of their leading parentheses.
+     When <replaceable>subexpr</replaceable> is omitted or zero, the result
+     identifies the position of the whole match regardless of
+     parenthesized subexpressions.
+    </para>
+
+    <para>
+     Some examples:
+<programlisting>
+regexp_instr('number of your street, town zip, FR', '[^,]+', 1, 2)
+                                   <lineannotation>23</lineannotation>
+regexp_instr(string=>'ABCDEFGHI', pattern=>'(c..)(...)', start=>1, "N"=>1, endoption=>0, flags=>'i', subexpr=>2)
+                                   <lineannotation>6</lineannotation>
+</programlisting>
+    </para>
+
+    <para>
+     The <function>regexp_like</function> function checks whether a match
+     of a POSIX regular expression pattern occurs within a string,
+     returning boolean true or false.  It has the syntax
+     <function>regexp_like</function>(<replaceable>string</replaceable>,
+     <replaceable>pattern</replaceable>
+     <optional>, <replaceable>flags</replaceable> </optional>).
+     The <replaceable>flags</replaceable> parameter is an optional text
+     string containing zero or more single-letter flags that change the
+     function's behavior.  Supported flags are described
+     in <xref linkend="posix-embedded-options-table"/>.
+     This function has the same results as the <literal>~</literal>
+     operator if no flags are specified.  If only the <literal>i</literal>
+     flag is specified, it has the same results as
+     the <literal>~*</literal> operator.
+    </para>
+
+    <para>
+     Some examples:
+<programlisting>
+regexp_like('Hello World', 'world')       <lineannotation>false</lineannotation>
+regexp_like('Hello World', 'world', 'i')  <lineannotation>true</lineannotation>
+</programlisting>
+    </para>
+
+    <para>
+     The <function>regexp_match</function> function returns a text array of
+     matching substring(s) within the first match of a POSIX
+     regular expression pattern to a string.  It has the syntax
+     <function>regexp_match</function>(<replaceable>string</replaceable>,
+     <replaceable>pattern</replaceable> <optional>, <replaceable>flags</replaceable> </optional>).
+     If there is no match, the result is <literal>NULL</literal>.
+     If a match is found, and the <replaceable>pattern</replaceable> contains no
+     parenthesized subexpressions, then the result is a single-element text
+     array containing the substring matching the whole pattern.
+     If a match is found, and the <replaceable>pattern</replaceable> contains
+     parenthesized subexpressions, then the result is a text array
+     whose <replaceable>n</replaceable>'th element is the substring matching
+     the <replaceable>n</replaceable>'th parenthesized subexpression of
+     the <replaceable>pattern</replaceable> (not counting <quote>non-capturing</quote>
+     parentheses; see below for details).
+     The <replaceable>flags</replaceable> parameter is an optional text string
+     containing zero or more single-letter flags that change the function's
+     behavior.  Supported flags are described
+     in <xref linkend="posix-embedded-options-table"/>.
+    </para>
+
+   <para>
+    Some examples:
+<programlisting>
+SELECT regexp_match('foobarbequebaz', 'bar.*que');
+ regexp_match
+--------------
+ {barbeque}
+(1 row)
+
+SELECT regexp_match('foobarbequebaz', '(bar)(beque)');
+ regexp_match
+--------------
+ {bar,beque}
+(1 row)
+</programlisting>
+   </para>
+
+    <tip>
+     <para>
+      In the common case where you just want the whole matching substring
+      or <literal>NULL</literal> for no match, the best solution is to
+      use <function>regexp_substr()</function>.
+      However, <function>regexp_substr()</function> only exists
+      in <productname>PostgreSQL</productname> version 15 and up.  When
+      working in older versions, you can extract the first element
+      of <function>regexp_match()</function>'s result, for example:
+<programlisting>
+SELECT (regexp_match('foobarbequebaz', 'bar.*que'))[1];
+ regexp_match
+--------------
+ barbeque
+(1 row)
+</programlisting>
+     </para>
+    </tip>
+
+    <para>
+     The <function>regexp_matches</function> function returns a set of text arrays
+     of matching substring(s) within matches of a POSIX regular
+     expression pattern to a string.  It has the same syntax as
+     <function>regexp_match</function>.
+     This function returns no rows if there is no match, one row if there is
+     a match and the <literal>g</literal> flag is not given, or <replaceable>N</replaceable>
+     rows if there are <replaceable>N</replaceable> matches and the <literal>g</literal> flag
+     is given.  Each returned row is a text array containing the whole
+     matched substring or the substrings matching parenthesized
+     subexpressions of the <replaceable>pattern</replaceable>, just as described above
+     for <function>regexp_match</function>.
+     <function>regexp_matches</function> accepts all the flags shown
+     in <xref linkend="posix-embedded-options-table"/>, plus
+     the <literal>g</literal> flag which commands it to return all matches, not
+     just the first one.
+    </para>
+
+   <para>
+    Some examples:
+<programlisting>
+SELECT regexp_matches('foo', 'not there');
+ regexp_matches
+----------------
+(0 rows)
+
+SELECT regexp_matches('foobarbequebazilbarfbonk', '(b[^b]+)(b[^b]+)', 'g');
+ regexp_matches
+----------------
+ {bar,beque}
+ {bazil,barf}
+(2 rows)
+</programlisting>
+   </para>
+
+   <tip>
+    <para>
+     In most cases <function>regexp_matches()</function> should be used with
+     the <literal>g</literal> flag, since if you only want the first match, it's
+     easier and more efficient to use <function>regexp_match()</function>.
+     However, <function>regexp_match()</function> only exists
+     in <productname>PostgreSQL</productname> version 10 and up.  When working in older
+     versions, a common trick is to place a <function>regexp_matches()</function>
+     call in a sub-select, for example:
+<programlisting>
+SELECT col1, (SELECT regexp_matches(col2, '(bar)(beque)')) FROM tab;
+</programlisting>
+     This produces a text array if there's a match, or <literal>NULL</literal> if
+     not, the same as <function>regexp_match()</function> would do.  Without the
+     sub-select, this query would produce no output at all for table rows
+     without a match, which is typically not the desired behavior.
+    </para>
+   </tip>
+
+    <para>
+     The <function>regexp_replace</function> function provides substitution of
+     new text for substrings that match POSIX regular expression patterns.
+     It has the syntax
+     <function>regexp_replace</function>(<replaceable>string</replaceable>,
+     <replaceable>pattern</replaceable>, <replaceable>replacement</replaceable>
+     <optional>, <replaceable>flags</replaceable> </optional>)
+     or
+     <function>regexp_replace</function>(<replaceable>string</replaceable>,
+     <replaceable>pattern</replaceable>, <replaceable>replacement</replaceable>,
+     <replaceable>start</replaceable>
+     <optional>, <replaceable>N</replaceable>
+     <optional>, <replaceable>flags</replaceable> </optional></optional>).
+     The source <replaceable>string</replaceable> is returned unchanged if
+     there is no match to the <replaceable>pattern</replaceable>.  If there is a
+     match, the <replaceable>string</replaceable> is returned with the
+     <replaceable>replacement</replaceable> string substituted for the matching
+     substring.  The <replaceable>replacement</replaceable> string can contain
+     <literal>\</literal><replaceable>n</replaceable>, where <replaceable>n</replaceable> is 1
+     through 9, to indicate that the source substring matching the
+     <replaceable>n</replaceable>'th parenthesized subexpression of the pattern should be
+     inserted, and it can contain <literal>\&amp;</literal> to indicate that the
+     substring matching the entire pattern should be inserted.  Write
+     <literal>\\</literal> if you need to put a literal backslash in the replacement
+     text.
+     <replaceable>pattern</replaceable> is searched for
+     in <replaceable>string</replaceable>, normally from the beginning of
+     the string, but if the <replaceable>start</replaceable> parameter is
+     provided then beginning from that character index.
+     By default, only the first match of the pattern is replaced.
+     If <replaceable>N</replaceable> is specified and is greater than zero,
+     then the <replaceable>N</replaceable>'th match of the pattern
+     is replaced.
+     If the <literal>g</literal> flag is given, or
+     if <replaceable>N</replaceable> is specified and is zero, then all
+     matches at or after the <replaceable>start</replaceable> position are
+     replaced.  (The <literal>g</literal> flag is ignored
+     when <replaceable>N</replaceable> is specified.)
+     The <replaceable>flags</replaceable> parameter is an optional text
+     string containing zero or more single-letter flags that change the
+     function's behavior.  Supported flags (though
+     not <literal>g</literal>) are
+     described in <xref linkend="posix-embedded-options-table"/>.
+    </para>
+
+   <para>
+    Some examples:
+<programlisting>
+regexp_replace('foobarbaz', 'b..', 'X')
+                                   <lineannotation>fooXbaz</lineannotation>
+regexp_replace('foobarbaz', 'b..', 'X', 'g')
+                                   <lineannotation>fooXX</lineannotation>
+regexp_replace('foobarbaz', 'b(..)', 'X\1Y', 'g')
+                                   <lineannotation>fooXarYXazY</lineannotation>
+regexp_replace('A PostgreSQL function', 'a|e|i|o|u', 'X', 1, 0, 'i')
+                                   <lineannotation>X PXstgrXSQL fXnctXXn</lineannotation>
+regexp_replace(string=>'A PostgreSQL function', pattern=>'a|e|i|o|u', replacement=>'X', start=>1, "N"=>3, flags=>'i')
+                                   <lineannotation>A PostgrXSQL function</lineannotation>
+</programlisting>
+   </para>
+
+    <para>
+     The <function>regexp_split_to_table</function> function splits a string using a POSIX
+     regular expression pattern as a delimiter.  It has the syntax
+     <function>regexp_split_to_table</function>(<replaceable>string</replaceable>, <replaceable>pattern</replaceable>
+     <optional>, <replaceable>flags</replaceable> </optional>).
+     If there is no match to the <replaceable>pattern</replaceable>, the function returns the
+     <replaceable>string</replaceable>.  If there is at least one match, for each match it returns
+     the text from the end of the last match (or the beginning of the string)
+     to the beginning of the match.  When there are no more matches, it
+     returns the text from the end of the last match to the end of the string.
+     The <replaceable>flags</replaceable> parameter is an optional text string containing
+     zero or more single-letter flags that change the function's behavior.
+     <function>regexp_split_to_table</function> supports the flags described in
+     <xref linkend="posix-embedded-options-table"/>.
+    </para>
+
+    <para>
+     The <function>regexp_split_to_array</function> function behaves the same as
+     <function>regexp_split_to_table</function>, except that <function>regexp_split_to_array</function>
+     returns its result as an array of <type>text</type>.  It has the syntax
+     <function>regexp_split_to_array</function>(<replaceable>string</replaceable>, <replaceable>pattern</replaceable>
+     <optional>, <replaceable>flags</replaceable> </optional>).
+     The parameters are the same as for <function>regexp_split_to_table</function>.
+    </para>
+
+   <para>
+    Some examples:
+<programlisting>
+SELECT foo FROM regexp_split_to_table('the quick brown fox jumps over the lazy dog', '\s+') AS foo;
+  foo
+-------
+ the
+ quick
+ brown
+ fox
+ jumps
+ over
+ the
+ lazy
+ dog
+(9 rows)
+
+SELECT regexp_split_to_array('the quick brown fox jumps over the lazy dog', '\s+');
+              regexp_split_to_array
+-----------------------------------------------
+ {the,quick,brown,fox,jumps,over,the,lazy,dog}
+(1 row)
+
+SELECT foo FROM regexp_split_to_table('the quick brown fox', '\s*') AS foo;
+ foo
+-----
+ t
+ h
+ e
+ q
+ u
+ i
+ c
+ k
+ b
+ r
+ o
+ w
+ n
+ f
+ o
+ x
+(16 rows)
+</programlisting>
+   </para>
+
+   <para>
+    As the last example demonstrates, the regexp split functions ignore
+    zero-length matches that occur at the start or end of the string
+    or immediately after a previous match.  This is contrary to the strict
+    definition of regexp matching that is implemented by
+    the other regexp functions, but is usually the most convenient behavior
+    in practice.  Other software systems such as Perl use similar definitions.
+   </para>
+
+    <para>
+     The <function>regexp_substr</function> function returns the substring
+     that matches a POSIX regular expression pattern,
+     or <literal>NULL</literal> if there is no match.  It has the syntax
+     <function>regexp_substr</function>(<replaceable>string</replaceable>,
+     <replaceable>pattern</replaceable>
+     <optional>, <replaceable>start</replaceable>
+     <optional>, <replaceable>N</replaceable>
+     <optional>, <replaceable>flags</replaceable>
+     <optional>, <replaceable>subexpr</replaceable>
+     </optional></optional></optional></optional>).
+     <replaceable>pattern</replaceable> is searched for
+     in <replaceable>string</replaceable>, normally from the beginning of
+     the string, but if the <replaceable>start</replaceable> parameter is
+     provided then beginning from that character index.
+     If <replaceable>N</replaceable> is specified
+     then the <replaceable>N</replaceable>'th match of the pattern
+     is returned, otherwise the first match is returned.
+     The <replaceable>flags</replaceable> parameter is an optional text
+     string containing zero or more single-letter flags that change the
+     function's behavior.  Supported flags are described
+     in <xref linkend="posix-embedded-options-table"/>.
+     For a pattern containing parenthesized
+     subexpressions, <replaceable>subexpr</replaceable> is an integer
+     indicating which subexpression is of interest: the result is the
+     substring matching that subexpression.
+     Subexpressions are numbered in the order of their leading parentheses.
+     When <replaceable>subexpr</replaceable> is omitted or zero, the result
+     is the whole match regardless of parenthesized subexpressions.
+    </para>
+
+    <para>
+     Some examples:
+<programlisting>
+regexp_substr('number of your street, town zip, FR', '[^,]+', 1, 2)
+                                   <lineannotation> town zip</lineannotation>
+regexp_substr('ABCDEFGHI', '(c..)(...)', 1, 1, 'i', 2)
+                                   <lineannotation>FGH</lineannotation>
+</programlisting>
+    </para>
+
+<!-- derived from the re_syntax.n man page -->
+
+   <sect3 id="posix-syntax-details">
+    <title>Regular Expression Details</title>
+
+   <para>
+    <productname>PostgreSQL</productname>'s regular expressions are implemented
+    using a software package written by Henry Spencer.  Much of
+    the description of regular expressions below is copied verbatim from his
+    manual.
+   </para>
+
+   <para>
+    Regular expressions (<acronym>RE</acronym>s), as defined in
+    <acronym>POSIX</acronym> 1003.2, come in two forms:
+    <firstterm>extended</firstterm> <acronym>RE</acronym>s or <acronym>ERE</acronym>s
+    (roughly those of <command>egrep</command>), and
+    <firstterm>basic</firstterm> <acronym>RE</acronym>s or <acronym>BRE</acronym>s
+    (roughly those of <command>ed</command>).
+    <productname>PostgreSQL</productname> supports both forms, and
+    also implements some extensions
+    that are not in the POSIX standard, but have become widely used
+    due to their availability in programming languages such as Perl and Tcl.
+    <acronym>RE</acronym>s using these non-POSIX extensions are called
+    <firstterm>advanced</firstterm> <acronym>RE</acronym>s or <acronym>ARE</acronym>s
+    in this documentation.  AREs are almost an exact superset of EREs,
+    but BREs have several notational incompatibilities (as well as being
+    much more limited).
+    We first describe the ARE and ERE forms, noting features that apply
+    only to AREs, and then describe how BREs differ.
+   </para>
+
+   <note>
+    <para>
+     <productname>PostgreSQL</productname> always initially presumes that a regular
+     expression follows the ARE rules.  However, the more limited ERE or
+     BRE rules can be chosen by prepending an <firstterm>embedded option</firstterm>
+     to the RE pattern, as described in <xref linkend="posix-metasyntax"/>.
+     This can be useful for compatibility with applications that expect
+     exactly the <acronym>POSIX</acronym> 1003.2 rules.
+    </para>
+   </note>
+
+   <para>
+    A regular expression is defined as one or more
+    <firstterm>branches</firstterm>, separated by
+    <literal>|</literal>.  It matches anything that matches one of the
+    branches.
+   </para>
+
+   <para>
+    A branch is zero or more <firstterm>quantified atoms</firstterm> or
+    <firstterm>constraints</firstterm>, concatenated.
+    It matches a match for the first, followed by a match for the second, etc.;
+    an empty branch matches the empty string.
+   </para>
+
+   <para>
+    A quantified atom is an <firstterm>atom</firstterm> possibly followed
+    by a single <firstterm>quantifier</firstterm>.
+    Without a quantifier, it matches a match for the atom.
+    With a quantifier, it can match some number of matches of the atom.
+    An <firstterm>atom</firstterm> can be any of the possibilities
+    shown in <xref linkend="posix-atoms-table"/>.
+    The possible quantifiers and their meanings are shown in
+    <xref linkend="posix-quantifiers-table"/>.
+   </para>
+
+   <para>
+    A <firstterm>constraint</firstterm> matches an empty string, but matches only when
+    specific conditions are met.  A constraint can be used where an atom
+    could be used, except it cannot be followed by a quantifier.
+    The simple constraints are shown in
+    <xref linkend="posix-constraints-table"/>;
+    some more constraints are described later.
+   </para>
+
+
+   <table id="posix-atoms-table">
+    <title>Regular Expression Atoms</title>
+
+    <tgroup cols="2">
+     <thead>
+      <row>
+       <entry>Atom</entry>
+       <entry>Description</entry>
+      </row>
+     </thead>
+
+      <tbody>
+       <row>
+       <entry> <literal>(</literal><replaceable>re</replaceable><literal>)</literal> </entry>
+       <entry> (where <replaceable>re</replaceable> is any regular expression)
+       matches a match for
+       <replaceable>re</replaceable>, with the match noted for possible reporting </entry>
+       </row>
+
+       <row>
+       <entry> <literal>(?:</literal><replaceable>re</replaceable><literal>)</literal> </entry>
+       <entry> as above, but the match is not noted for reporting
+       (a <quote>non-capturing</quote> set of parentheses)
+       (AREs only) </entry>
+       </row>
+
+       <row>
+       <entry> <literal>.</literal> </entry>
+       <entry> matches any single character </entry>
+       </row>
+
+       <row>
+       <entry> <literal>[</literal><replaceable>chars</replaceable><literal>]</literal> </entry>
+       <entry> a <firstterm>bracket expression</firstterm>,
+       matching any one of the <replaceable>chars</replaceable> (see
+       <xref linkend="posix-bracket-expressions"/> for more detail) </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\</literal><replaceable>k</replaceable> </entry>
+       <entry> (where <replaceable>k</replaceable> is a non-alphanumeric character)
+       matches that character taken as an ordinary character,
+       e.g., <literal>\\</literal> matches a backslash character </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\</literal><replaceable>c</replaceable> </entry>
+       <entry> where <replaceable>c</replaceable> is alphanumeric
+       (possibly followed by other characters)
+       is an <firstterm>escape</firstterm>, see <xref linkend="posix-escape-sequences"/>
+       (AREs only; in EREs and BREs, this matches <replaceable>c</replaceable>) </entry>
+       </row>
+
+       <row>
+       <entry> <literal>{</literal> </entry>
+       <entry> when followed by a character other than a digit,
+       matches the left-brace character <literal>{</literal>;
+       when followed by a digit, it is the beginning of a
+       <replaceable>bound</replaceable> (see below) </entry>
+       </row>
+
+       <row>
+       <entry> <replaceable>x</replaceable> </entry>
+       <entry> where <replaceable>x</replaceable> is a single character with no other
+       significance, matches that character </entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+   <para>
+    An RE cannot end with a backslash (<literal>\</literal>).
+   </para>
+
+   <note>
+    <para>
+     If you have <xref linkend="guc-standard-conforming-strings"/> turned off,
+     any backslashes you write in literal string constants will need to be
+     doubled.  See <xref linkend="sql-syntax-strings"/> for more information.
+    </para>
+   </note>
+
+   <table id="posix-quantifiers-table">
+    <title>Regular Expression Quantifiers</title>
+
+    <tgroup cols="2">
+     <thead>
+      <row>
+       <entry>Quantifier</entry>
+       <entry>Matches</entry>
+      </row>
+     </thead>
+
+      <tbody>
+       <row>
+       <entry> <literal>*</literal> </entry>
+       <entry> a sequence of 0 or more matches of the atom </entry>
+       </row>
+
+       <row>
+       <entry> <literal>+</literal> </entry>
+       <entry> a sequence of 1 or more matches of the atom </entry>
+       </row>
+
+       <row>
+       <entry> <literal>?</literal> </entry>
+       <entry> a sequence of 0 or 1 matches of the atom </entry>
+       </row>
+
+       <row>
+       <entry> <literal>{</literal><replaceable>m</replaceable><literal>}</literal> </entry>
+       <entry> a sequence of exactly <replaceable>m</replaceable> matches of the atom </entry>
+       </row>
+
+       <row>
+       <entry> <literal>{</literal><replaceable>m</replaceable><literal>,}</literal> </entry>
+       <entry> a sequence of <replaceable>m</replaceable> or more matches of the atom </entry>
+       </row>
+
+       <row>
+       <entry>
+       <literal>{</literal><replaceable>m</replaceable><literal>,</literal><replaceable>n</replaceable><literal>}</literal> </entry>
+       <entry> a sequence of <replaceable>m</replaceable> through <replaceable>n</replaceable>
+       (inclusive) matches of the atom; <replaceable>m</replaceable> cannot exceed
+       <replaceable>n</replaceable> </entry>
+       </row>
+
+       <row>
+       <entry> <literal>*?</literal> </entry>
+       <entry> non-greedy version of <literal>*</literal> </entry>
+       </row>
+
+       <row>
+       <entry> <literal>+?</literal> </entry>
+       <entry> non-greedy version of <literal>+</literal> </entry>
+       </row>
+
+       <row>
+       <entry> <literal>??</literal> </entry>
+       <entry> non-greedy version of <literal>?</literal> </entry>
+       </row>
+
+       <row>
+       <entry> <literal>{</literal><replaceable>m</replaceable><literal>}?</literal> </entry>
+       <entry> non-greedy version of <literal>{</literal><replaceable>m</replaceable><literal>}</literal> </entry>
+       </row>
+
+       <row>
+       <entry> <literal>{</literal><replaceable>m</replaceable><literal>,}?</literal> </entry>
+       <entry> non-greedy version of <literal>{</literal><replaceable>m</replaceable><literal>,}</literal> </entry>
+       </row>
+
+       <row>
+       <entry>
+       <literal>{</literal><replaceable>m</replaceable><literal>,</literal><replaceable>n</replaceable><literal>}?</literal> </entry>
+       <entry> non-greedy version of <literal>{</literal><replaceable>m</replaceable><literal>,</literal><replaceable>n</replaceable><literal>}</literal> </entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+   <para>
+    The forms using <literal>{</literal><replaceable>...</replaceable><literal>}</literal>
+    are known as <firstterm>bounds</firstterm>.
+    The numbers <replaceable>m</replaceable> and <replaceable>n</replaceable> within a bound are
+    unsigned decimal integers with permissible values from 0 to 255 inclusive.
+   </para>
+
+    <para>
+     <firstterm>Non-greedy</firstterm> quantifiers (available in AREs only) match the
+     same possibilities as their corresponding normal (<firstterm>greedy</firstterm>)
+     counterparts, but prefer the smallest number rather than the largest
+     number of matches.
+     See <xref linkend="posix-matching-rules"/> for more detail.
+   </para>
+
+   <note>
+    <para>
+     A quantifier cannot immediately follow another quantifier, e.g.,
+     <literal>**</literal> is invalid.
+     A quantifier cannot
+     begin an expression or subexpression or follow
+     <literal>^</literal> or <literal>|</literal>.
+    </para>
+   </note>
+
+   <table id="posix-constraints-table">
+    <title>Regular Expression Constraints</title>
+
+    <tgroup cols="2">
+     <thead>
+      <row>
+       <entry>Constraint</entry>
+       <entry>Description</entry>
+      </row>
+     </thead>
+
+      <tbody>
+       <row>
+       <entry> <literal>^</literal> </entry>
+       <entry> matches at the beginning of the string </entry>
+       </row>
+
+       <row>
+       <entry> <literal>$</literal> </entry>
+       <entry> matches at the end of the string </entry>
+       </row>
+
+       <row>
+       <entry> <literal>(?=</literal><replaceable>re</replaceable><literal>)</literal> </entry>
+       <entry> <firstterm>positive lookahead</firstterm> matches at any point
+       where a substring matching <replaceable>re</replaceable> begins
+       (AREs only) </entry>
+       </row>
+
+       <row>
+       <entry> <literal>(?!</literal><replaceable>re</replaceable><literal>)</literal> </entry>
+       <entry> <firstterm>negative lookahead</firstterm> matches at any point
+       where no substring matching <replaceable>re</replaceable> begins
+       (AREs only) </entry>
+       </row>
+
+       <row>
+       <entry> <literal>(?&lt;=</literal><replaceable>re</replaceable><literal>)</literal> </entry>
+       <entry> <firstterm>positive lookbehind</firstterm> matches at any point
+       where a substring matching <replaceable>re</replaceable> ends
+       (AREs only) </entry>
+       </row>
+
+       <row>
+       <entry> <literal>(?&lt;!</literal><replaceable>re</replaceable><literal>)</literal> </entry>
+       <entry> <firstterm>negative lookbehind</firstterm> matches at any point
+       where no substring matching <replaceable>re</replaceable> ends
+       (AREs only) </entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+   <para>
+    Lookahead and lookbehind constraints cannot contain <firstterm>back
+    references</firstterm> (see <xref linkend="posix-escape-sequences"/>),
+    and all parentheses within them are considered non-capturing.
+   </para>
+   </sect3>
+
+   <sect3 id="posix-bracket-expressions">
+    <title>Bracket Expressions</title>
+
+   <para>
+    A <firstterm>bracket expression</firstterm> is a list of
+    characters enclosed in <literal>[]</literal>.  It normally matches
+    any single character from the list (but see below).  If the list
+    begins with <literal>^</literal>, it matches any single character
+    <emphasis>not</emphasis> from the rest of the list.
+    If two characters
+    in the list are separated by <literal>-</literal>, this is
+    shorthand for the full range of characters between those two
+    (inclusive) in the collating sequence,
+    e.g., <literal>[0-9]</literal> in <acronym>ASCII</acronym> matches
+    any decimal digit.  It is illegal for two ranges to share an
+    endpoint, e.g.,  <literal>a-c-e</literal>.  Ranges are very
+    collating-sequence-dependent, so portable programs should avoid
+    relying on them.
+   </para>
+
+   <para>
+    To include a literal <literal>]</literal> in the list, make it the
+    first character (after <literal>^</literal>, if that is used).  To
+    include a literal <literal>-</literal>, make it the first or last
+    character, or the second endpoint of a range.  To use a literal
+    <literal>-</literal> as the first endpoint of a range, enclose it
+    in <literal>[.</literal> and <literal>.]</literal> to make it a
+    collating element (see below).  With the exception of these characters,
+    some combinations using <literal>[</literal>
+    (see next paragraphs), and escapes (AREs only), all other special
+    characters lose their special significance within a bracket expression.
+    In particular, <literal>\</literal> is not special when following
+    ERE or BRE rules, though it is special (as introducing an escape)
+    in AREs.
+   </para>
+
+   <para>
+    Within a bracket expression, a collating element (a character, a
+    multiple-character sequence that collates as if it were a single
+    character, or a collating-sequence name for either) enclosed in
+    <literal>[.</literal> and <literal>.]</literal> stands for the
+    sequence of characters of that collating element.  The sequence is
+    treated as a single element of the bracket expression's list.  This
+    allows a bracket
+    expression containing a multiple-character collating element to
+    match more than one character, e.g., if the collating sequence
+    includes a <literal>ch</literal> collating element, then the RE
+    <literal>[[.ch.]]*c</literal> matches the first five characters of
+    <literal>chchcc</literal>.
+   </para>
+
+   <note>
+    <para>
+     <productname>PostgreSQL</productname> currently does not support multi-character collating
+     elements. This information describes possible future behavior.
+    </para>
+   </note>
+
+   <para>
+    Within a bracket expression, a collating element enclosed in
+    <literal>[=</literal> and <literal>=]</literal> is an <firstterm>equivalence
+    class</firstterm>, standing for the sequences of characters of all collating
+    elements equivalent to that one, including itself.  (If there are
+    no other equivalent collating elements, the treatment is as if the
+    enclosing delimiters were <literal>[.</literal> and
+    <literal>.]</literal>.)  For example, if <literal>o</literal> and
+    <literal>^</literal> are the members of an equivalence class, then
+    <literal>[[=o=]]</literal>, <literal>[[=^=]]</literal>, and
+    <literal>[o^]</literal> are all synonymous.  An equivalence class
+    cannot be an endpoint of a range.
+   </para>
+
+   <para>
+    Within a bracket expression, the name of a character class
+    enclosed in <literal>[:</literal> and <literal>:]</literal> stands
+    for the list of all characters belonging to that class.  A character
+    class cannot be used as an endpoint of a range.
+    The <acronym>POSIX</acronym> standard defines these character class
+    names:
+    <literal>alnum</literal> (letters and numeric digits),
+    <literal>alpha</literal> (letters),
+    <literal>blank</literal> (space and tab),
+    <literal>cntrl</literal> (control characters),
+    <literal>digit</literal> (numeric digits),
+    <literal>graph</literal> (printable characters except space),
+    <literal>lower</literal> (lower-case letters),
+    <literal>print</literal> (printable characters including space),
+    <literal>punct</literal> (punctuation),
+    <literal>space</literal> (any white space),
+    <literal>upper</literal> (upper-case letters),
+    and <literal>xdigit</literal> (hexadecimal digits).
+    The behavior of these standard character classes is generally
+    consistent across platforms for characters in the 7-bit ASCII set.
+    Whether a given non-ASCII character is considered to belong to one
+    of these classes depends on the <firstterm>collation</firstterm>
+    that is used for the regular-expression function or operator
+    (see <xref linkend="collation"/>), or by default on the
+    database's <envar>LC_CTYPE</envar> locale setting (see
+    <xref linkend="locale"/>).  The classification of non-ASCII
+    characters can vary across platforms even in similarly-named
+    locales.  (But the <literal>C</literal> locale never considers any
+    non-ASCII characters to belong to any of these classes.)
+    In addition to these standard character
+    classes, <productname>PostgreSQL</productname> defines
+    the <literal>word</literal> character class, which is the same as
+    <literal>alnum</literal> plus the underscore (<literal>_</literal>)
+    character, and
+    the <literal>ascii</literal> character class, which contains exactly
+    the 7-bit ASCII set.
+   </para>
+
+   <para>
+    There are two special cases of bracket expressions:  the bracket
+    expressions <literal>[[:&lt;:]]</literal> and
+    <literal>[[:&gt;:]]</literal> are constraints,
+    matching empty strings at the beginning
+    and end of a word respectively.  A word is defined as a sequence
+    of word characters that is neither preceded nor followed by word
+    characters.  A word character is any character belonging to the
+    <literal>word</literal> character class, that is, any letter, digit,
+    or underscore.  This is an extension, compatible with but not
+    specified by <acronym>POSIX</acronym> 1003.2, and should be used with
+    caution in software intended to be portable to other systems.
+    The constraint escapes described below are usually preferable; they
+    are no more standard, but are easier to type.
+   </para>
+   </sect3>
+
+   <sect3 id="posix-escape-sequences">
+    <title>Regular Expression Escapes</title>
+
+   <para>
+    <firstterm>Escapes</firstterm> are special sequences beginning with <literal>\</literal>
+    followed by an alphanumeric character. Escapes come in several varieties:
+    character entry, class shorthands, constraint escapes, and back references.
+    A <literal>\</literal> followed by an alphanumeric character but not constituting
+    a valid escape is illegal in AREs.
+    In EREs, there are no escapes: outside a bracket expression,
+    a <literal>\</literal> followed by an alphanumeric character merely stands for
+    that character as an ordinary character, and inside a bracket expression,
+    <literal>\</literal> is an ordinary character.
+    (The latter is the one actual incompatibility between EREs and AREs.)
+   </para>
+
+   <para>
+    <firstterm>Character-entry escapes</firstterm> exist to make it easier to specify
+    non-printing and other inconvenient characters in REs.  They are
+    shown in <xref linkend="posix-character-entry-escapes-table"/>.
+   </para>
+
+   <para>
+    <firstterm>Class-shorthand escapes</firstterm> provide shorthands for certain
+    commonly-used character classes.  They are
+    shown in <xref linkend="posix-class-shorthand-escapes-table"/>.
+   </para>
+
+   <para>
+    A <firstterm>constraint escape</firstterm> is a constraint,
+    matching the empty string if specific conditions are met,
+    written as an escape.  They are
+    shown in <xref linkend="posix-constraint-escapes-table"/>.
+   </para>
+
+   <para>
+    A <firstterm>back reference</firstterm> (<literal>\</literal><replaceable>n</replaceable>) matches the
+    same string matched by the previous parenthesized subexpression specified
+    by the number <replaceable>n</replaceable>
+    (see <xref linkend="posix-constraint-backref-table"/>).  For example,
+    <literal>([bc])\1</literal> matches <literal>bb</literal> or <literal>cc</literal>
+    but not <literal>bc</literal> or <literal>cb</literal>.
+    The subexpression must entirely precede the back reference in the RE.
+    Subexpressions are numbered in the order of their leading parentheses.
+    Non-capturing parentheses do not define subexpressions.
+    The back reference considers only the string characters matched by the
+    referenced subexpression, not any constraints contained in it.  For
+    example, <literal>(^\d)\1</literal> will match <literal>22</literal>.
+   </para>
+
+   <table id="posix-character-entry-escapes-table">
+    <title>Regular Expression Character-Entry Escapes</title>
+
+    <tgroup cols="2">
+     <thead>
+      <row>
+       <entry>Escape</entry>
+       <entry>Description</entry>
+      </row>
+     </thead>
+
+      <tbody>
+       <row>
+       <entry> <literal>\a</literal> </entry>
+       <entry> alert (bell) character, as in C </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\b</literal> </entry>
+       <entry> backspace, as in C </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\B</literal> </entry>
+       <entry> synonym for backslash (<literal>\</literal>) to help reduce the need for backslash
+       doubling </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\c</literal><replaceable>X</replaceable> </entry>
+       <entry> (where <replaceable>X</replaceable> is any character) the character whose
+       low-order 5 bits are the same as those of
+       <replaceable>X</replaceable>, and whose other bits are all zero </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\e</literal> </entry>
+       <entry> the character whose collating-sequence name
+       is <literal>ESC</literal>,
+       or failing that, the character with octal value <literal>033</literal> </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\f</literal> </entry>
+       <entry> form feed, as in C </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\n</literal> </entry>
+       <entry> newline, as in C </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\r</literal> </entry>
+       <entry> carriage return, as in C </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\t</literal> </entry>
+       <entry> horizontal tab, as in C </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\u</literal><replaceable>wxyz</replaceable> </entry>
+       <entry> (where <replaceable>wxyz</replaceable> is exactly four hexadecimal digits)
+       the character whose hexadecimal value is
+       <literal>0x</literal><replaceable>wxyz</replaceable>
+       </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\U</literal><replaceable>stuvwxyz</replaceable> </entry>
+       <entry> (where <replaceable>stuvwxyz</replaceable> is exactly eight hexadecimal
+       digits)
+       the character whose hexadecimal value is
+       <literal>0x</literal><replaceable>stuvwxyz</replaceable>
+       </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\v</literal> </entry>
+       <entry> vertical tab, as in C </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\x</literal><replaceable>hhh</replaceable> </entry>
+       <entry> (where <replaceable>hhh</replaceable> is any sequence of hexadecimal
+       digits)
+       the character whose hexadecimal value is
+       <literal>0x</literal><replaceable>hhh</replaceable>
+       (a single character no matter how many hexadecimal digits are used)
+       </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\0</literal> </entry>
+       <entry> the character whose value is <literal>0</literal> (the null byte)</entry>
+       </row>
+
+       <row>
+       <entry> <literal>\</literal><replaceable>xy</replaceable> </entry>
+       <entry> (where <replaceable>xy</replaceable> is exactly two octal digits,
+       and is not a <firstterm>back reference</firstterm>)
+       the character whose octal value is
+       <literal>0</literal><replaceable>xy</replaceable> </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\</literal><replaceable>xyz</replaceable> </entry>
+       <entry> (where <replaceable>xyz</replaceable> is exactly three octal digits,
+       and is not a <firstterm>back reference</firstterm>)
+       the character whose octal value is
+       <literal>0</literal><replaceable>xyz</replaceable> </entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+   <para>
+    Hexadecimal digits are <literal>0</literal>-<literal>9</literal>,
+    <literal>a</literal>-<literal>f</literal>, and <literal>A</literal>-<literal>F</literal>.
+    Octal digits are <literal>0</literal>-<literal>7</literal>.
+   </para>
+
+   <para>
+    Numeric character-entry escapes specifying values outside the ASCII range
+    (0&ndash;127) have meanings dependent on the database encoding.  When the
+    encoding is UTF-8, escape values are equivalent to Unicode code points,
+    for example <literal>\u1234</literal> means the character <literal>U+1234</literal>.
+    For other multibyte encodings, character-entry escapes usually just
+    specify the concatenation of the byte values for the character.  If the
+    escape value does not correspond to any legal character in the database
+    encoding, no error will be raised, but it will never match any data.
+   </para>
+
+   <para>
+    The character-entry escapes are always taken as ordinary characters.
+    For example, <literal>\135</literal> is <literal>]</literal> in ASCII, but
+    <literal>\135</literal> does not terminate a bracket expression.
+   </para>
+
+   <table id="posix-class-shorthand-escapes-table">
+    <title>Regular Expression Class-Shorthand Escapes</title>
+
+    <tgroup cols="2">
+     <thead>
+      <row>
+       <entry>Escape</entry>
+       <entry>Description</entry>
+      </row>
+     </thead>
+
+      <tbody>
+       <row>
+       <entry> <literal>\d</literal> </entry>
+       <entry> matches any digit, like
+        <literal>[[:digit:]]</literal> </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\s</literal> </entry>
+       <entry> matches any whitespace character, like
+        <literal>[[:space:]]</literal> </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\w</literal> </entry>
+       <entry> matches any word character, like
+        <literal>[[:word:]]</literal> </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\D</literal> </entry>
+       <entry> matches any non-digit, like
+        <literal>[^[:digit:]]</literal> </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\S</literal> </entry>
+       <entry> matches any non-whitespace character, like
+        <literal>[^[:space:]]</literal> </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\W</literal> </entry>
+       <entry> matches any non-word character, like
+        <literal>[^[:word:]]</literal> </entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+   <para>
+    The class-shorthand escapes also work within bracket expressions,
+    although the definitions shown above are not quite syntactically
+    valid in that context.
+    For example, <literal>[a-c\d]</literal> is equivalent to
+    <literal>[a-c[:digit:]]</literal>.
+   </para>
+
+   <table id="posix-constraint-escapes-table">
+    <title>Regular Expression Constraint Escapes</title>
+
+    <tgroup cols="2">
+     <thead>
+      <row>
+       <entry>Escape</entry>
+       <entry>Description</entry>
+      </row>
+     </thead>
+
+      <tbody>
+       <row>
+       <entry> <literal>\A</literal> </entry>
+       <entry> matches only at the beginning of the string
+       (see <xref linkend="posix-matching-rules"/> for how this differs from
+       <literal>^</literal>) </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\m</literal> </entry>
+       <entry> matches only at the beginning of a word </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\M</literal> </entry>
+       <entry> matches only at the end of a word </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\y</literal> </entry>
+       <entry> matches only at the beginning or end of a word </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\Y</literal> </entry>
+       <entry> matches only at a point that is not the beginning or end of a
+       word </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\Z</literal> </entry>
+       <entry> matches only at the end of the string
+       (see <xref linkend="posix-matching-rules"/> for how this differs from
+       <literal>$</literal>) </entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+   <para>
+    A word is defined as in the specification of
+    <literal>[[:&lt;:]]</literal> and <literal>[[:&gt;:]]</literal> above.
+    Constraint escapes are illegal within bracket expressions.
+   </para>
+
+   <table id="posix-constraint-backref-table">
+    <title>Regular Expression Back References</title>
+
+    <tgroup cols="2">
+     <thead>
+      <row>
+       <entry>Escape</entry>
+       <entry>Description</entry>
+      </row>
+     </thead>
+
+      <tbody>
+       <row>
+       <entry> <literal>\</literal><replaceable>m</replaceable> </entry>
+       <entry> (where <replaceable>m</replaceable> is a nonzero digit)
+       a back reference to the <replaceable>m</replaceable>'th subexpression </entry>
+       </row>
+
+       <row>
+       <entry> <literal>\</literal><replaceable>mnn</replaceable> </entry>
+       <entry> (where <replaceable>m</replaceable> is a nonzero digit, and
+       <replaceable>nn</replaceable> is some more digits, and the decimal value
+       <replaceable>mnn</replaceable> is not greater than the number of closing capturing
+       parentheses seen so far)
+       a back reference to the <replaceable>mnn</replaceable>'th subexpression </entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+   <note>
+    <para>
+     There is an inherent ambiguity between octal character-entry
+     escapes and back references, which is resolved by the following heuristics,
+     as hinted at above.
+     A leading zero always indicates an octal escape.
+     A single non-zero digit, not followed by another digit,
+     is always taken as a back reference.
+     A multi-digit sequence not starting with a zero is taken as a back
+     reference if it comes after a suitable subexpression
+     (i.e., the number is in the legal range for a back reference),
+     and otherwise is taken as octal.
+    </para>
+   </note>
+   </sect3>
+
+   <sect3 id="posix-metasyntax">
+    <title>Regular Expression Metasyntax</title>
+
+   <para>
+    In addition to the main syntax described above, there are some special
+    forms and miscellaneous syntactic facilities available.
+   </para>
+
+   <para>
+    An RE can begin with one of two special <firstterm>director</firstterm> prefixes.
+    If an RE begins with <literal>***:</literal>,
+    the rest of the RE is taken as an ARE.  (This normally has no effect in
+    <productname>PostgreSQL</productname>, since REs are assumed to be AREs;
+    but it does have an effect if ERE or BRE mode had been specified by
+    the <replaceable>flags</replaceable> parameter to a regex function.)
+    If an RE begins with <literal>***=</literal>,
+    the rest of the RE is taken to be a literal string,
+    with all characters considered ordinary characters.
+   </para>
+
+   <para>
+    An ARE can begin with <firstterm>embedded options</firstterm>:
+    a sequence <literal>(?</literal><replaceable>xyz</replaceable><literal>)</literal>
+    (where <replaceable>xyz</replaceable> is one or more alphabetic characters)
+    specifies options affecting the rest of the RE.
+    These options override any previously determined options &mdash;
+    in particular, they can override the case-sensitivity behavior implied by
+    a regex operator, or the <replaceable>flags</replaceable> parameter to a regex
+    function.
+    The available option letters are
+    shown in <xref linkend="posix-embedded-options-table"/>.
+    Note that these same option letters are used in the <replaceable>flags</replaceable>
+    parameters of regex functions.
+   </para>
+
+   <table id="posix-embedded-options-table">
+    <title>ARE Embedded-Option Letters</title>
+
+    <tgroup cols="2">
+     <thead>
+      <row>
+       <entry>Option</entry>
+       <entry>Description</entry>
+      </row>
+     </thead>
+
+      <tbody>
+       <row>
+       <entry> <literal>b</literal> </entry>
+       <entry> rest of RE is a BRE </entry>
+       </row>
+
+       <row>
+       <entry> <literal>c</literal> </entry>
+       <entry> case-sensitive matching (overrides operator type) </entry>
+       </row>
+
+       <row>
+       <entry> <literal>e</literal> </entry>
+       <entry> rest of RE is an ERE </entry>
+       </row>
+
+       <row>
+       <entry> <literal>i</literal> </entry>
+       <entry> case-insensitive matching (see
+       <xref linkend="posix-matching-rules"/>) (overrides operator type) </entry>
+       </row>
+
+       <row>
+       <entry> <literal>m</literal> </entry>
+       <entry> historical synonym for <literal>n</literal> </entry>
+       </row>
+
+       <row>
+       <entry> <literal>n</literal> </entry>
+       <entry> newline-sensitive matching (see
+       <xref linkend="posix-matching-rules"/>) </entry>
+       </row>
+
+       <row>
+       <entry> <literal>p</literal> </entry>
+       <entry> partial newline-sensitive matching (see
+       <xref linkend="posix-matching-rules"/>) </entry>
+       </row>
+
+       <row>
+       <entry> <literal>q</literal> </entry>
+       <entry> rest of RE is a literal (<quote>quoted</quote>) string, all ordinary
+       characters </entry>
+       </row>
+
+       <row>
+       <entry> <literal>s</literal> </entry>
+       <entry> non-newline-sensitive matching (default) </entry>
+       </row>
+
+       <row>
+       <entry> <literal>t</literal> </entry>
+       <entry> tight syntax (default; see below) </entry>
+       </row>
+
+       <row>
+       <entry> <literal>w</literal> </entry>
+       <entry> inverse partial newline-sensitive (<quote>weird</quote>) matching
+       (see <xref linkend="posix-matching-rules"/>) </entry>
+       </row>
+
+       <row>
+       <entry> <literal>x</literal> </entry>
+       <entry> expanded syntax (see below) </entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+   <para>
+    Embedded options take effect at the <literal>)</literal> terminating the sequence.
+    They can appear only at the start of an ARE (after the
+    <literal>***:</literal> director if any).
+   </para>
+
+   <para>
+    In addition to the usual (<firstterm>tight</firstterm>) RE syntax, in which all
+    characters are significant, there is an <firstterm>expanded</firstterm> syntax,
+    available by specifying the embedded <literal>x</literal> option.
+    In the expanded syntax,
+    white-space characters in the RE are ignored, as are
+    all characters between a <literal>#</literal>
+    and the following newline (or the end of the RE).  This
+    permits paragraphing and commenting a complex RE.
+    There are three exceptions to that basic rule:
+
+    <itemizedlist>
+     <listitem>
+      <para>
+       a white-space character or <literal>#</literal> preceded by <literal>\</literal> is
+       retained
+      </para>
+     </listitem>
+     <listitem>
+      <para>
+       white space or <literal>#</literal> within a bracket expression is retained
+      </para>
+     </listitem>
+     <listitem>
+      <para>
+       white space and comments cannot appear within multi-character symbols,
+       such as <literal>(?:</literal>
+      </para>
+     </listitem>
+    </itemizedlist>
+
+    For this purpose, white-space characters are blank, tab, newline, and
+    any character that belongs to the <replaceable>space</replaceable> character class.
+   </para>
+
+   <para>
+    Finally, in an ARE, outside bracket expressions, the sequence
+    <literal>(?#</literal><replaceable>ttt</replaceable><literal>)</literal>
+    (where <replaceable>ttt</replaceable> is any text not containing a <literal>)</literal>)
+    is a comment, completely ignored.
+    Again, this is not allowed between the characters of
+    multi-character symbols, like <literal>(?:</literal>.
+    Such comments are more a historical artifact than a useful facility,
+    and their use is deprecated; use the expanded syntax instead.
+   </para>
+
+   <para>
+    <emphasis>None</emphasis> of these metasyntax extensions is available if
+    an initial <literal>***=</literal> director
+    has specified that the user's input be treated as a literal string
+    rather than as an RE.
+   </para>
+   </sect3>
+
+   <sect3 id="posix-matching-rules">
+    <title>Regular Expression Matching Rules</title>
+
+   <para>
+    In the event that an RE could match more than one substring of a given
+    string, the RE matches the one starting earliest in the string.
+    If the RE could match more than one substring starting at that point,
+    either the longest possible match or the shortest possible match will
+    be taken, depending on whether the RE is <firstterm>greedy</firstterm> or
+    <firstterm>non-greedy</firstterm>.
+   </para>
+
+   <para>
+    Whether an RE is greedy or not is determined by the following rules:
+    <itemizedlist>
+     <listitem>
+      <para>
+       Most atoms, and all constraints, have no greediness attribute (because
+       they cannot match variable amounts of text anyway).
+      </para>
+     </listitem>
+     <listitem>
+      <para>
+       Adding parentheses around an RE does not change its greediness.
+      </para>
+     </listitem>
+     <listitem>
+      <para>
+       A quantified atom with a fixed-repetition quantifier
+       (<literal>{</literal><replaceable>m</replaceable><literal>}</literal>
+       or
+       <literal>{</literal><replaceable>m</replaceable><literal>}?</literal>)
+       has the same greediness (possibly none) as the atom itself.
+      </para>
+     </listitem>
+     <listitem>
+      <para>
+       A quantified atom with other normal quantifiers (including
+       <literal>{</literal><replaceable>m</replaceable><literal>,</literal><replaceable>n</replaceable><literal>}</literal>
+       with <replaceable>m</replaceable> equal to <replaceable>n</replaceable>)
+       is greedy (prefers longest match).
+      </para>
+     </listitem>
+     <listitem>
+      <para>
+       A quantified atom with a non-greedy quantifier (including
+       <literal>{</literal><replaceable>m</replaceable><literal>,</literal><replaceable>n</replaceable><literal>}?</literal>
+       with <replaceable>m</replaceable> equal to <replaceable>n</replaceable>)
+       is non-greedy (prefers shortest match).
+      </para>
+     </listitem>
+     <listitem>
+      <para>
+       A branch &mdash; that is, an RE that has no top-level
+       <literal>|</literal> operator &mdash; has the same greediness as the first
+       quantified atom in it that has a greediness attribute.
+      </para>
+     </listitem>
+     <listitem>
+      <para>
+       An RE consisting of two or more branches connected by the
+       <literal>|</literal> operator is always greedy.
+      </para>
+     </listitem>
+    </itemizedlist>
+   </para>
+
+   <para>
+    The above rules associate greediness attributes not only with individual
+    quantified atoms, but with branches and entire REs that contain quantified
+    atoms.  What that means is that the matching is done in such a way that
+    the branch, or whole RE, matches the longest or shortest possible
+    substring <emphasis>as a whole</emphasis>.  Once the length of the entire match
+    is determined, the part of it that matches any particular subexpression
+    is determined on the basis of the greediness attribute of that
+    subexpression, with subexpressions starting earlier in the RE taking
+    priority over ones starting later.
+   </para>
+
+   <para>
+    An example of what this means:
+<screen>
+SELECT SUBSTRING('XY1234Z', 'Y*([0-9]{1,3})');
+<lineannotation>Result: </lineannotation><computeroutput>123</computeroutput>
+SELECT SUBSTRING('XY1234Z', 'Y*?([0-9]{1,3})');
+<lineannotation>Result: </lineannotation><computeroutput>1</computeroutput>
+</screen>
+    In the first case, the RE as a whole is greedy because <literal>Y*</literal>
+    is greedy.  It can match beginning at the <literal>Y</literal>, and it matches
+    the longest possible string starting there, i.e., <literal>Y123</literal>.
+    The output is the parenthesized part of that, or <literal>123</literal>.
+    In the second case, the RE as a whole is non-greedy because <literal>Y*?</literal>
+    is non-greedy.  It can match beginning at the <literal>Y</literal>, and it matches
+    the shortest possible string starting there, i.e., <literal>Y1</literal>.
+    The subexpression <literal>[0-9]{1,3}</literal> is greedy but it cannot change
+    the decision as to the overall match length; so it is forced to match
+    just <literal>1</literal>.
+   </para>
+
+   <para>
+    In short, when an RE contains both greedy and non-greedy subexpressions,
+    the total match length is either as long as possible or as short as
+    possible, according to the attribute assigned to the whole RE.  The
+    attributes assigned to the subexpressions only affect how much of that
+    match they are allowed to <quote>eat</quote> relative to each other.
+   </para>
+
+   <para>
+    The quantifiers <literal>{1,1}</literal> and <literal>{1,1}?</literal>
+    can be used to force greediness or non-greediness, respectively,
+    on a subexpression or a whole RE.
+    This is useful when you need the whole RE to have a greediness attribute
+    different from what's deduced from its elements.  As an example,
+    suppose that we are trying to separate a string containing some digits
+    into the digits and the parts before and after them.  We might try to
+    do that like this:
+<screen>
+SELECT regexp_match('abc01234xyz', '(.*)(\d+)(.*)');
+<lineannotation>Result: </lineannotation><computeroutput>{abc0123,4,xyz}</computeroutput>
+</screen>
+    That didn't work: the first <literal>.*</literal> is greedy so
+    it <quote>eats</quote> as much as it can, leaving the <literal>\d+</literal> to
+    match at the last possible place, the last digit.  We might try to fix
+    that by making it non-greedy:
+<screen>
+SELECT regexp_match('abc01234xyz', '(.*?)(\d+)(.*)');
+<lineannotation>Result: </lineannotation><computeroutput>{abc,0,""}</computeroutput>
+</screen>
+    That didn't work either, because now the RE as a whole is non-greedy
+    and so it ends the overall match as soon as possible.  We can get what
+    we want by forcing the RE as a whole to be greedy:
+<screen>
+SELECT regexp_match('abc01234xyz', '(?:(.*?)(\d+)(.*)){1,1}');
+<lineannotation>Result: </lineannotation><computeroutput>{abc,01234,xyz}</computeroutput>
+</screen>
+    Controlling the RE's overall greediness separately from its components'
+    greediness allows great flexibility in handling variable-length patterns.
+   </para>
+
+   <para>
+    When deciding what is a longer or shorter match,
+    match lengths are measured in characters, not collating elements.
+    An empty string is considered longer than no match at all.
+    For example:
+    <literal>bb*</literal>
+    matches the three middle characters of <literal>abbbc</literal>;
+    <literal>(week|wee)(night|knights)</literal>
+    matches all ten characters of <literal>weeknights</literal>;
+    when <literal>(.*).*</literal>
+    is matched against <literal>abc</literal> the parenthesized subexpression
+    matches all three characters; and when
+    <literal>(a*)*</literal> is matched against <literal>bc</literal>
+    both the whole RE and the parenthesized
+    subexpression match an empty string.
+   </para>
+
+   <para>
+    If case-independent matching is specified,
+    the effect is much as if all case distinctions had vanished from the
+    alphabet.
+    When an alphabetic that exists in multiple cases appears as an
+    ordinary character outside a bracket expression, it is effectively
+    transformed into a bracket expression containing both cases,
+    e.g., <literal>x</literal> becomes <literal>[xX]</literal>.
+    When it appears inside a bracket expression, all case counterparts
+    of it are added to the bracket expression, e.g.,
+    <literal>[x]</literal> becomes <literal>[xX]</literal>
+    and <literal>[^x]</literal> becomes <literal>[^xX]</literal>.
+   </para>
+
+   <para>
+    If newline-sensitive matching is specified, <literal>.</literal>
+    and bracket expressions using <literal>^</literal>
+    will never match the newline character
+    (so that matches will not cross lines unless the RE
+    explicitly includes a newline)
+    and <literal>^</literal> and <literal>$</literal>
+    will match the empty string after and before a newline
+    respectively, in addition to matching at beginning and end of string
+    respectively.
+    But the ARE escapes <literal>\A</literal> and <literal>\Z</literal>
+    continue to match beginning or end of string <emphasis>only</emphasis>.
+    Also, the character class shorthands <literal>\D</literal>
+    and <literal>\W</literal> will match a newline regardless of this mode.
+    (Before <productname>PostgreSQL</productname> 14, they did not match
+    newlines when in newline-sensitive mode.
+    Write <literal>[^[:digit:]]</literal>
+    or <literal>[^[:word:]]</literal> to get the old behavior.)
+   </para>
+
+   <para>
+    If partial newline-sensitive matching is specified,
+    this affects <literal>.</literal> and bracket expressions
+    as with newline-sensitive matching, but not <literal>^</literal>
+    and <literal>$</literal>.
+   </para>
+
+   <para>
+    If inverse partial newline-sensitive matching is specified,
+    this affects <literal>^</literal> and <literal>$</literal>
+    as with newline-sensitive matching, but not <literal>.</literal>
+    and bracket expressions.
+    This isn't very useful but is provided for symmetry.
+   </para>
+   </sect3>
+
+   <sect3 id="posix-limits-compatibility">
+    <title>Limits and Compatibility</title>
+
+   <para>
+    No particular limit is imposed on the length of REs in this
+    implementation.  However,
+    programs intended to be highly portable should not employ REs longer
+    than 256 bytes,
+    as a POSIX-compliant implementation can refuse to accept such REs.
+   </para>
+
+   <para>
+    The only feature of AREs that is actually incompatible with
+    POSIX EREs is that <literal>\</literal> does not lose its special
+    significance inside bracket expressions.
+    All other ARE features use syntax which is illegal or has
+    undefined or unspecified effects in POSIX EREs;
+    the <literal>***</literal> syntax of directors likewise is outside the POSIX
+    syntax for both BREs and EREs.
+   </para>
+
+   <para>
+    Many of the ARE extensions are borrowed from Perl, but some have
+    been changed to clean them up, and a few Perl extensions are not present.
+    Incompatibilities of note include <literal>\b</literal>, <literal>\B</literal>,
+    the lack of special treatment for a trailing newline,
+    the addition of complemented bracket expressions to the things
+    affected by newline-sensitive matching,
+    the restrictions on parentheses and back references in lookahead/lookbehind
+    constraints, and the longest/shortest-match (rather than first-match)
+    matching semantics.
+   </para>
+   </sect3>
+
+   <sect3 id="posix-basic-regexes">
+    <title>Basic Regular Expressions</title>
+
+   <para>
+    BREs differ from EREs in several respects.
+    In BREs, <literal>|</literal>, <literal>+</literal>, and <literal>?</literal>
+    are ordinary characters and there is no equivalent
+    for their functionality.
+    The delimiters for bounds are
+    <literal>\{</literal> and <literal>\}</literal>,
+    with <literal>{</literal> and <literal>}</literal>
+    by themselves ordinary characters.
+    The parentheses for nested subexpressions are
+    <literal>\(</literal> and <literal>\)</literal>,
+    with <literal>(</literal> and <literal>)</literal> by themselves ordinary characters.
+    <literal>^</literal> is an ordinary character except at the beginning of the
+    RE or the beginning of a parenthesized subexpression,
+    <literal>$</literal> is an ordinary character except at the end of the
+    RE or the end of a parenthesized subexpression,
+    and <literal>*</literal> is an ordinary character if it appears at the beginning
+    of the RE or the beginning of a parenthesized subexpression
+    (after a possible leading <literal>^</literal>).
+    Finally, single-digit back references are available, and
+    <literal>\&lt;</literal> and <literal>\&gt;</literal>
+    are synonyms for
+    <literal>[[:&lt;:]]</literal> and <literal>[[:&gt;:]]</literal>
+    respectively; no other escapes are available in BREs.
+   </para>
+   </sect3>
+
+<!-- end re_syntax.n man page -->
+
+   <sect3 id="posix-vs-xquery">
+   <title>Differences from SQL Standard and XQuery</title>
+
+   <indexterm zone="posix-vs-xquery">
+    <primary>LIKE_REGEX</primary>
+   </indexterm>
+
+   <indexterm zone="posix-vs-xquery">
+    <primary>OCCURRENCES_REGEX</primary>
+   </indexterm>
+
+   <indexterm zone="posix-vs-xquery">
+    <primary>POSITION_REGEX</primary>
+   </indexterm>
+
+   <indexterm zone="posix-vs-xquery">
+    <primary>SUBSTRING_REGEX</primary>
+   </indexterm>
+
+   <indexterm zone="posix-vs-xquery">
+    <primary>TRANSLATE_REGEX</primary>
+   </indexterm>
+
+   <indexterm zone="posix-vs-xquery">
+    <primary>XQuery regular expressions</primary>
+   </indexterm>
+
+    <para>
+     Since SQL:2008, the SQL standard includes regular expression operators
+     and functions that performs pattern
+     matching according to the XQuery regular expression
+     standard:
+     <itemizedlist>
+      <listitem><para><literal>LIKE_REGEX</literal></para></listitem>
+      <listitem><para><literal>OCCURRENCES_REGEX</literal></para></listitem>
+      <listitem><para><literal>POSITION_REGEX</literal></para></listitem>
+      <listitem><para><literal>SUBSTRING_REGEX</literal></para></listitem>
+      <listitem><para><literal>TRANSLATE_REGEX</literal></para></listitem>
+     </itemizedlist>
+     <productname>PostgreSQL</productname> does not currently implement these
+     operators and functions.  You can get approximately equivalent
+     functionality in each case as shown in <xref
+     linkend="functions-regexp-sql-table"/>.  (Various optional clauses on
+     both sides have been omitted in this table.)
+    </para>
+
+    <table id="functions-regexp-sql-table">
+     <title>Regular Expression Functions Equivalencies</title>
+
+     <tgroup cols="2">
+      <thead>
+       <row>
+        <entry>SQL standard</entry>
+        <entry><productname>PostgreSQL</productname></entry>
+       </row>
+      </thead>
+
+      <tbody>
+       <row>
+        <entry><literal><replaceable>string</replaceable> LIKE_REGEX <replaceable>pattern</replaceable></literal></entry>
+        <entry><literal>regexp_like(<replaceable>string</replaceable>, <replaceable>pattern</replaceable>)</literal> or <literal><replaceable>string</replaceable> ~ <replaceable>pattern</replaceable></literal></entry>
+       </row>
+
+       <row>
+        <entry><literal>OCCURRENCES_REGEX(<replaceable>pattern</replaceable> IN <replaceable>string</replaceable>)</literal></entry>
+        <entry><literal>regexp_count(<replaceable>string</replaceable>, <replaceable>pattern</replaceable>)</literal></entry>
+       </row>
+
+       <row>
+        <entry><literal>POSITION_REGEX(<replaceable>pattern</replaceable> IN <replaceable>string</replaceable>)</literal></entry>
+        <entry><literal>regexp_instr(<replaceable>string</replaceable>, <replaceable>pattern</replaceable>)</literal></entry>
+       </row>
+
+       <row>
+        <entry><literal>SUBSTRING_REGEX(<replaceable>pattern</replaceable> IN <replaceable>string</replaceable>)</literal></entry>
+        <entry><literal>regexp_substr(<replaceable>string</replaceable>, <replaceable>pattern</replaceable>)</literal></entry>
+       </row>
+
+       <row>
+        <entry><literal>TRANSLATE_REGEX(<replaceable>pattern</replaceable> IN <replaceable>string</replaceable> WITH <replaceable>replacement</replaceable>)</literal></entry>
+        <entry><literal>regexp_replace(<replaceable>string</replaceable>, <replaceable>pattern</replaceable>, <replaceable>replacement</replaceable>)</literal></entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </table>
+
+    <para>
+     Regular expression functions similar to those provided by PostgreSQL are
+     also available in a number of other SQL implementations, whereas the
+     SQL-standard functions are not as widely implemented.  Some of the
+     details of the regular expression syntax will likely differ in each
+     implementation.
+    </para>
+
+    <para>
+     The SQL-standard operators and functions use XQuery regular expressions,
+     which are quite close to the ARE syntax described above.
+     Notable differences between the existing POSIX-based
+     regular-expression feature and XQuery regular expressions include:
+
+     <itemizedlist>
+      <listitem>
+       <para>
+        XQuery character class subtraction is not supported.  An example of
+        this feature is using the following to match only English
+        consonants: <literal>[a-z-[aeiou]]</literal>.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        XQuery character class shorthands <literal>\c</literal>,
+        <literal>\C</literal>, <literal>\i</literal>,
+        and <literal>\I</literal> are not supported.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        XQuery character class elements
+        using <literal>\p{UnicodeProperty}</literal> or the
+        inverse <literal>\P{UnicodeProperty}</literal> are not supported.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        POSIX interprets character classes such as <literal>\w</literal>
+        (see <xref linkend="posix-class-shorthand-escapes-table"/>)
+        according to the prevailing locale (which you can control by
+        attaching a <literal>COLLATE</literal> clause to the operator or
+        function).  XQuery specifies these classes by reference to Unicode
+        character properties, so equivalent behavior is obtained only with
+        a locale that follows the Unicode rules.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        The SQL standard (not XQuery itself) attempts to cater for more
+        variants of <quote>newline</quote> than POSIX does.  The
+        newline-sensitive matching options described above consider only
+        ASCII NL (<literal>\n</literal>) to be a newline, but SQL would have
+        us treat CR (<literal>\r</literal>), CRLF (<literal>\r\n</literal>)
+        (a Windows-style newline), and some Unicode-only characters like
+        LINE SEPARATOR (U+2028) as newlines as well.
+        Notably, <literal>.</literal> and <literal>\s</literal> should
+        count <literal>\r\n</literal> as one character not two according to
+        SQL.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        Of the character-entry escapes described in
+        <xref linkend="posix-character-entry-escapes-table"/>,
+        XQuery supports only <literal>\n</literal>, <literal>\r</literal>,
+        and <literal>\t</literal>.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        XQuery does not support
+        the <literal>[:<replaceable>name</replaceable>:]</literal> syntax
+        for character classes within bracket expressions.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        XQuery does not have lookahead or lookbehind constraints,
+        nor any of the constraint escapes described in
+        <xref linkend="posix-constraint-escapes-table"/>.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        The metasyntax forms described in <xref linkend="posix-metasyntax"/>
+        do not exist in XQuery.
+       </para>
+      </listitem>
+      <listitem>
+       <para>
+        The regular expression flag letters defined by XQuery are
+        related to but not the same as the option letters for POSIX
+        (<xref linkend="posix-embedded-options-table"/>).  While the
+        <literal>i</literal> and <literal>q</literal> options behave the
+        same, others do not:
+        <itemizedlist>
+         <listitem>
+          <para>
+           XQuery's <literal>s</literal> (allow dot to match newline)
+           and <literal>m</literal> (allow <literal>^</literal>
+           and <literal>$</literal> to match at newlines) flags provide
+           access to the same behaviors as
+           POSIX's <literal>n</literal>, <literal>p</literal>
+           and <literal>w</literal> flags, but they
+           do <emphasis>not</emphasis> match the behavior of
+           POSIX's <literal>s</literal> and <literal>m</literal> flags.
+           Note in particular that dot-matches-newline is the default
+           behavior in POSIX but not XQuery.
+          </para>
+         </listitem>
+         <listitem>
+          <para>
+           XQuery's <literal>x</literal> (ignore whitespace in pattern) flag
+           is noticeably different from POSIX's expanded-mode flag.
+           POSIX's <literal>x</literal> flag also
+           allows <literal>#</literal> to begin a comment in the pattern,
+           and POSIX will not ignore a whitespace character after a
+           backslash.
+          </para>
+         </listitem>
+        </itemizedlist>
+       </para>
+      </listitem>
+     </itemizedlist>
+    </para>
+
+   </sect3>
+  </sect2>
+ </sect1>
diff --git a/doc/src/sgml/func/func-math.sgml b/doc/src/sgml/func/func-math.sgml
new file mode 100644
index 0000000000000..7528dc4cea4b9
--- /dev/null
+++ b/doc/src/sgml/func/func-math.sgml
@@ -0,0 +1,1615 @@
+  <sect1 id="functions-math">
+   <title>Mathematical Functions and Operators</title>
+
+   <para>
+    Mathematical operators are provided for many
+    <productname>PostgreSQL</productname> types. For types without
+    standard mathematical conventions
+    (e.g., date/time types) we
+    describe the actual behavior in subsequent sections.
+   </para>
+
+   <para>
+    <xref linkend="functions-math-op-table"/> shows the mathematical
+    operators that are available for the standard numeric types.
+    Unless otherwise noted, operators shown as
+    accepting <replaceable>numeric_type</replaceable> are available for all
+    the types <type>smallint</type>, <type>integer</type>,
+    <type>bigint</type>, <type>numeric</type>, <type>real</type>,
+    and <type>double precision</type>.
+    Operators shown as accepting <replaceable>integral_type</replaceable>
+    are available for the types <type>smallint</type>, <type>integer</type>,
+    and <type>bigint</type>.
+    Except where noted, each form of an operator returns the same data type
+    as its argument(s).  Calls involving multiple argument data types, such
+    as <type>integer</type> <literal>+</literal> <type>numeric</type>,
+    are resolved by using the type appearing later in these lists.
+   </para>
+
+   <table id="functions-math-op-table">
+    <title>Mathematical Operators</title>
+
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Operator
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>numeric_type</replaceable> <literal>+</literal> <replaceable>numeric_type</replaceable>
+        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Addition
+       </para>
+       <para>
+        <literal>2 + 3</literal>
+        <returnvalue>5</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>+</literal> <replaceable>numeric_type</replaceable>
+        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Unary plus (no operation)
+       </para>
+       <para>
+        <literal>+ 3.5</literal>
+        <returnvalue>3.5</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>numeric_type</replaceable> <literal>-</literal> <replaceable>numeric_type</replaceable>
+        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Subtraction
+       </para>
+       <para>
+        <literal>2 - 3</literal>
+        <returnvalue>-1</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>-</literal> <replaceable>numeric_type</replaceable>
+        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Negation
+       </para>
+       <para>
+        <literal>- (-4)</literal>
+        <returnvalue>4</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>numeric_type</replaceable> <literal>*</literal> <replaceable>numeric_type</replaceable>
+        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Multiplication
+       </para>
+       <para>
+        <literal>2 * 3</literal>
+        <returnvalue>6</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>numeric_type</replaceable> <literal>/</literal> <replaceable>numeric_type</replaceable>
+        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Division (for integral types, division truncates the result towards
+        zero)
+       </para>
+       <para>
+        <literal>5.0 / 2</literal>
+        <returnvalue>2.5000000000000000</returnvalue>
+       </para>
+       <para>
+        <literal>5 / 2</literal>
+        <returnvalue>2</returnvalue>
+       </para>
+       <para>
+        <literal>(-5) / 2</literal>
+        <returnvalue>-2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>numeric_type</replaceable> <literal>%</literal> <replaceable>numeric_type</replaceable>
+        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Modulo (remainder); available for <type>smallint</type>,
+        <type>integer</type>, <type>bigint</type>, and <type>numeric</type>
+       </para>
+       <para>
+        <literal>5 % 4</literal>
+        <returnvalue>1</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>numeric</type> <literal>^</literal> <type>numeric</type>
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <type>double precision</type> <literal>^</literal> <type>double precision</type>
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Exponentiation
+       </para>
+       <para>
+        <literal>2 ^ 3</literal>
+        <returnvalue>8</returnvalue>
+       </para>
+       <para>
+        Unlike typical mathematical practice, multiple uses of
+        <literal>^</literal> will associate left to right by default:
+       </para>
+       <para>
+        <literal>2 ^ 3 ^ 3</literal>
+        <returnvalue>512</returnvalue>
+       </para>
+       <para>
+        <literal>2 ^ (3 ^ 3)</literal>
+        <returnvalue>134217728</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>|/</literal> <type>double precision</type>
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Square root
+       </para>
+       <para>
+        <literal>|/ 25.0</literal>
+        <returnvalue>5</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>||/</literal> <type>double precision</type>
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Cube root
+       </para>
+       <para>
+        <literal>||/ 64.0</literal>
+        <returnvalue>4</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>@</literal> <replaceable>numeric_type</replaceable>
+        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Absolute value
+       </para>
+       <para>
+        <literal>@ -5.0</literal>
+        <returnvalue>5.0</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>integral_type</replaceable> <literal>&amp;</literal> <replaceable>integral_type</replaceable>
+        <returnvalue><replaceable>integral_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Bitwise AND
+       </para>
+       <para>
+        <literal>91 &amp; 15</literal>
+        <returnvalue>11</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>integral_type</replaceable> <literal>|</literal> <replaceable>integral_type</replaceable>
+        <returnvalue><replaceable>integral_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Bitwise OR
+       </para>
+       <para>
+        <literal>32 | 3</literal>
+        <returnvalue>35</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>integral_type</replaceable> <literal>#</literal> <replaceable>integral_type</replaceable>
+        <returnvalue><replaceable>integral_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Bitwise exclusive OR
+       </para>
+       <para>
+        <literal>17 # 5</literal>
+        <returnvalue>20</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>~</literal> <replaceable>integral_type</replaceable>
+        <returnvalue><replaceable>integral_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Bitwise NOT
+       </para>
+       <para>
+        <literal>~1</literal>
+        <returnvalue>-2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>integral_type</replaceable> <literal>&lt;&lt;</literal> <type>integer</type>
+        <returnvalue><replaceable>integral_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Bitwise shift left
+       </para>
+       <para>
+        <literal>1 &lt;&lt; 4</literal>
+        <returnvalue>16</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <replaceable>integral_type</replaceable> <literal>&gt;&gt;</literal> <type>integer</type>
+        <returnvalue><replaceable>integral_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Bitwise shift right
+       </para>
+       <para>
+        <literal>8 &gt;&gt; 2</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
+  <para>
+   <xref linkend="functions-math-func-table"/> shows the available
+   mathematical functions.
+   Many of these functions are provided in multiple forms with different
+   argument types.
+   Except where noted, any given form of a function returns the same
+   data type as its argument(s); cross-type cases are resolved in the
+   same way as explained above for operators.
+   The functions working with <type>double precision</type> data are mostly
+   implemented on top of the host system's C library; accuracy and behavior in
+   boundary cases can therefore vary depending on the host system.
+  </para>
+
+   <table id="functions-math-func-table">
+    <title>Mathematical Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>abs</primary>
+        </indexterm>
+        <function>abs</function> ( <replaceable>numeric_type</replaceable> )
+        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Absolute value
+       </para>
+       <para>
+        <literal>abs(-17.4)</literal>
+        <returnvalue>17.4</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>cbrt</primary>
+        </indexterm>
+        <function>cbrt</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Cube root
+       </para>
+       <para>
+        <literal>cbrt(64.0)</literal>
+        <returnvalue>4</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>ceil</primary>
+        </indexterm>
+        <function>ceil</function> ( <type>numeric</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>ceil</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Nearest integer greater than or equal to argument
+       </para>
+       <para>
+        <literal>ceil(42.2)</literal>
+        <returnvalue>43</returnvalue>
+       </para>
+       <para>
+        <literal>ceil(-42.8)</literal>
+        <returnvalue>-42</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>ceiling</primary>
+        </indexterm>
+        <function>ceiling</function> ( <type>numeric</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>ceiling</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Nearest integer greater than or equal to argument (same
+        as <function>ceil</function>)
+       </para>
+       <para>
+        <literal>ceiling(95.3)</literal>
+        <returnvalue>96</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>degrees</primary>
+        </indexterm>
+        <function>degrees</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Converts radians to degrees
+       </para>
+       <para>
+        <literal>degrees(0.5)</literal>
+        <returnvalue>28.64788975654116</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>div</primary>
+        </indexterm>
+        <function>div</function> ( <parameter>y</parameter> <type>numeric</type>,
+        <parameter>x</parameter> <type>numeric</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para>
+        Integer quotient of <parameter>y</parameter>/<parameter>x</parameter>
+        (truncates towards zero)
+       </para>
+       <para>
+        <literal>div(9, 4)</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>erf</primary>
+        </indexterm>
+        <function>erf</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Error function
+       </para>
+       <para>
+        <literal>erf(1.0)</literal>
+        <returnvalue>0.8427007929497149</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>erfc</primary>
+        </indexterm>
+        <function>erfc</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Complementary error function (<literal>1 - erf(x)</literal>, without
+        loss of precision for large inputs)
+       </para>
+       <para>
+        <literal>erfc(1.0)</literal>
+        <returnvalue>0.15729920705028513</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>exp</primary>
+        </indexterm>
+        <function>exp</function> ( <type>numeric</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>exp</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Exponential (<literal>e</literal> raised to the given power)
+       </para>
+       <para>
+        <literal>exp(1.0)</literal>
+        <returnvalue>2.7182818284590452</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm id="function-factorial">
+         <primary>factorial</primary>
+        </indexterm>
+        <function>factorial</function> ( <type>bigint</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para>
+        Factorial
+       </para>
+       <para>
+        <literal>factorial(5)</literal>
+        <returnvalue>120</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>floor</primary>
+        </indexterm>
+        <function>floor</function> ( <type>numeric</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>floor</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Nearest integer less than or equal to argument
+       </para>
+       <para>
+        <literal>floor(42.8)</literal>
+        <returnvalue>42</returnvalue>
+       </para>
+       <para>
+        <literal>floor(-42.8)</literal>
+        <returnvalue>-43</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>gamma</primary>
+        </indexterm>
+        <function>gamma</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Gamma function
+       </para>
+       <para>
+        <literal>gamma(0.5)</literal>
+        <returnvalue>1.772453850905516</returnvalue>
+       </para>
+       <para>
+        <literal>gamma(6)</literal>
+        <returnvalue>120</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>gcd</primary>
+        </indexterm>
+        <function>gcd</function> ( <replaceable>numeric_type</replaceable>, <replaceable>numeric_type</replaceable> )
+        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Greatest common divisor (the largest positive number that divides both
+        inputs with no remainder); returns <literal>0</literal> if both inputs
+        are zero; available for <type>integer</type>, <type>bigint</type>,
+        and <type>numeric</type>
+       </para>
+       <para>
+        <literal>gcd(1071, 462)</literal>
+        <returnvalue>21</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>lcm</primary>
+        </indexterm>
+        <function>lcm</function> ( <replaceable>numeric_type</replaceable>, <replaceable>numeric_type</replaceable> )
+        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Least common multiple (the smallest strictly positive number that is
+        an integral multiple of both inputs); returns <literal>0</literal> if
+        either input is zero; available for <type>integer</type>,
+        <type>bigint</type>, and <type>numeric</type>
+       </para>
+       <para>
+        <literal>lcm(1071, 462)</literal>
+        <returnvalue>23562</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>lgamma</primary>
+        </indexterm>
+        <function>lgamma</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Natural logarithm of the absolute value of the gamma function
+       </para>
+       <para>
+        <literal>lgamma(1000)</literal>
+        <returnvalue>5905.220423209181</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>ln</primary>
+        </indexterm>
+        <function>ln</function> ( <type>numeric</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>ln</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Natural logarithm
+       </para>
+       <para>
+        <literal>ln(2.0)</literal>
+        <returnvalue>0.6931471805599453</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>log</primary>
+        </indexterm>
+        <function>log</function> ( <type>numeric</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>log</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Base 10 logarithm
+       </para>
+       <para>
+        <literal>log(100)</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>log10</primary>
+        </indexterm>
+        <function>log10</function> ( <type>numeric</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>log10</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Base 10 logarithm (same as <function>log</function>)
+       </para>
+       <para>
+        <literal>log10(1000)</literal>
+        <returnvalue>3</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>log</function> ( <parameter>b</parameter> <type>numeric</type>,
+        <parameter>x</parameter> <type>numeric</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para>
+        Logarithm of <parameter>x</parameter> to base <parameter>b</parameter>
+       </para>
+       <para>
+       <literal>log(2.0, 64.0)</literal>
+       <returnvalue>6.0000000000000000</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>min_scale</primary>
+        </indexterm>
+        <function>min_scale</function> ( <type>numeric</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Minimum scale (number of fractional decimal digits) needed
+        to represent the supplied value precisely
+       </para>
+       <para>
+        <literal>min_scale(8.4100)</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>mod</primary>
+        </indexterm>
+        <function>mod</function> ( <parameter>y</parameter> <replaceable>numeric_type</replaceable>,
+        <parameter>x</parameter> <replaceable>numeric_type</replaceable> )
+        <returnvalue><replaceable>numeric_type</replaceable></returnvalue>
+       </para>
+       <para>
+        Remainder of <parameter>y</parameter>/<parameter>x</parameter>;
+        available for <type>smallint</type>, <type>integer</type>,
+        <type>bigint</type>, and <type>numeric</type>
+       </para>
+       <para>
+        <literal>mod(9, 4)</literal>
+        <returnvalue>1</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pi</primary>
+        </indexterm>
+        <function>pi</function> (  )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Approximate value of <phrase role="symbol_font">&pi;</phrase>
+       </para>
+       <para>
+        <literal>pi()</literal>
+        <returnvalue>3.141592653589793</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>power</primary>
+        </indexterm>
+        <function>power</function> ( <parameter>a</parameter> <type>numeric</type>,
+        <parameter>b</parameter> <type>numeric</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>power</function> ( <parameter>a</parameter> <type>double precision</type>,
+        <parameter>b</parameter> <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        <parameter>a</parameter> raised to the power of <parameter>b</parameter>
+       </para>
+       <para>
+        <literal>power(9, 3)</literal>
+        <returnvalue>729</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>radians</primary>
+        </indexterm>
+        <function>radians</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Converts degrees to radians
+       </para>
+       <para>
+        <literal>radians(45.0)</literal>
+        <returnvalue>0.7853981633974483</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>round</primary>
+        </indexterm>
+        <function>round</function> ( <type>numeric</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>round</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Rounds to nearest integer.  For <type>numeric</type>, ties are
+        broken by rounding away from zero.  For <type>double precision</type>,
+        the tie-breaking behavior is platform dependent, but
+        <quote>round to nearest even</quote> is the most common rule.
+       </para>
+       <para>
+        <literal>round(42.4)</literal>
+        <returnvalue>42</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>round</function> ( <parameter>v</parameter> <type>numeric</type>, <parameter>s</parameter> <type>integer</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para>
+        Rounds <parameter>v</parameter> to <parameter>s</parameter> decimal
+        places.  Ties are broken by rounding away from zero.
+       </para>
+       <para>
+        <literal>round(42.4382, 2)</literal>
+        <returnvalue>42.44</returnvalue>
+       </para>
+       <para>
+        <literal>round(1234.56, -1)</literal>
+        <returnvalue>1230</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>scale</primary>
+        </indexterm>
+        <function>scale</function> ( <type>numeric</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Scale of the argument (the number of decimal digits in the fractional part)
+       </para>
+       <para>
+        <literal>scale(8.4100)</literal>
+        <returnvalue>4</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>sign</primary>
+        </indexterm>
+        <function>sign</function> ( <type>numeric</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>sign</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Sign of the argument (-1, 0, or +1)
+       </para>
+       <para>
+        <literal>sign(-8.4)</literal>
+        <returnvalue>-1</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>sqrt</primary>
+        </indexterm>
+         <function>sqrt</function> ( <type>numeric</type> )
+         <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+         <function>sqrt</function> ( <type>double precision</type> )
+         <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Square root
+       </para>
+       <para>
+        <literal>sqrt(2)</literal>
+        <returnvalue>1.4142135623730951</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim_scale</primary>
+        </indexterm>
+        <function>trim_scale</function> ( <type>numeric</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para>
+        Reduces the value's scale (number of fractional decimal digits) by
+        removing trailing zeroes
+       </para>
+       <para>
+        <literal>trim_scale(8.4100)</literal>
+        <returnvalue>8.41</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trunc</primary>
+        </indexterm>
+        <function>trunc</function> ( <type>numeric</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>trunc</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Truncates to integer (towards zero)
+       </para>
+       <para>
+        <literal>trunc(42.8)</literal>
+        <returnvalue>42</returnvalue>
+       </para>
+       <para>
+        <literal>trunc(-42.8)</literal>
+        <returnvalue>-42</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>trunc</function> ( <parameter>v</parameter> <type>numeric</type>, <parameter>s</parameter> <type>integer</type> )
+       <returnvalue>numeric</returnvalue>
+       </para>
+       <para>
+        Truncates <parameter>v</parameter> to <parameter>s</parameter>
+        decimal places
+       </para>
+       <para>
+        <literal>trunc(42.4382, 2)</literal>
+        <returnvalue>42.43</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>width_bucket</primary>
+        </indexterm>
+        <function>width_bucket</function> ( <parameter>operand</parameter> <type>numeric</type>, <parameter>low</parameter> <type>numeric</type>, <parameter>high</parameter> <type>numeric</type>, <parameter>count</parameter> <type>integer</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>width_bucket</function> ( <parameter>operand</parameter> <type>double precision</type>, <parameter>low</parameter> <type>double precision</type>, <parameter>high</parameter> <type>double precision</type>, <parameter>count</parameter> <type>integer</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the number of the bucket in
+        which <parameter>operand</parameter> falls in a histogram
+        having <parameter>count</parameter> equal-width buckets spanning the
+        range <parameter>low</parameter> to <parameter>high</parameter>.
+        The buckets have inclusive lower bounds and exclusive upper bounds.
+        Returns <literal>0</literal> for an input less
+        than <parameter>low</parameter>,
+        or <literal><parameter>count</parameter>+1</literal> for an input
+        greater than or equal to <parameter>high</parameter>.
+        If <parameter>low</parameter> &gt; <parameter>high</parameter>,
+        the behavior is mirror-reversed, with bucket <literal>1</literal>
+        now being the one just below <parameter>low</parameter>, and the
+        inclusive bounds now being on the upper side.
+       </para>
+       <para>
+        <literal>width_bucket(5.35, 0.024, 10.06, 5)</literal>
+        <returnvalue>3</returnvalue>
+       </para>
+       <para>
+        <literal>width_bucket(9, 10, 0, 10)</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>width_bucket</function> ( <parameter>operand</parameter> <type>anycompatible</type>, <parameter>thresholds</parameter> <type>anycompatiblearray</type> )
+       <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the number of the bucket in
+        which <parameter>operand</parameter> falls given an array listing the
+        inclusive lower bounds of the buckets.
+        Returns <literal>0</literal> for an input less than the first lower
+        bound.  <parameter>operand</parameter> and the array elements can be
+        of any type having standard comparison operators.
+        The <parameter>thresholds</parameter> array <emphasis>must be
+        sorted</emphasis>, smallest first, or unexpected results will be
+        obtained.
+       </para>
+       <para>
+        <literal>width_bucket(now(), array['yesterday', 'today', 'tomorrow']::timestamptz[])</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <para>
+    <xref linkend="functions-math-random-table"/> shows functions for
+    generating random numbers.
+  </para>
+
+   <table id="functions-math-random-table">
+    <title>Random Functions</title>
+
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>random</primary>
+        </indexterm>
+        <function>random</function> ( )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Returns a random value in the range 0.0 &lt;= x &lt; 1.0
+       </para>
+       <para>
+        <literal>random()</literal>
+        <returnvalue>0.897124072839091</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>random</primary>
+        </indexterm>
+        <function>random</function> ( <parameter>min</parameter> <type>integer</type>, <parameter>max</parameter> <type>integer</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>random</function> ( <parameter>min</parameter> <type>bigint</type>, <parameter>max</parameter> <type>bigint</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>random</function> ( <parameter>min</parameter> <type>numeric</type>, <parameter>max</parameter> <type>numeric</type> )
+        <returnvalue>numeric</returnvalue>
+       </para>
+       <para>
+        Returns a random value in the range
+        <parameter>min</parameter> &lt;= x &lt;= <parameter>max</parameter>.
+        For type <type>numeric</type>, the result will have the same number of
+        fractional decimal digits as <parameter>min</parameter> or
+        <parameter>max</parameter>, whichever has more.
+       </para>
+       <para>
+        <literal>random(1, 10)</literal>
+        <returnvalue>7</returnvalue>
+       </para>
+       <para>
+        <literal>random(-0.499, 0.499)</literal>
+        <returnvalue>0.347</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>random_normal</primary>
+        </indexterm>
+
+         <function>random_normal</function> (
+         <optional> <parameter>mean</parameter> <type>double precision</type>
+         <optional>, <parameter>stddev</parameter> <type>double precision</type> </optional></optional> )
+         <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Returns a random value from the normal distribution with the given
+        parameters; <parameter>mean</parameter> defaults to 0.0
+        and <parameter>stddev</parameter> defaults to 1.0
+       </para>
+       <para>
+        <literal>random_normal(0.0, 1.0)</literal>
+        <returnvalue>0.051285419</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>setseed</primary>
+        </indexterm>
+        <function>setseed</function> ( <type>double precision</type> )
+        <returnvalue>void</returnvalue>
+       </para>
+       <para>
+        Sets the seed for subsequent <literal>random()</literal> and
+        <literal>random_normal()</literal> calls;
+        argument must be between -1.0 and 1.0, inclusive
+       </para>
+       <para>
+        <literal>setseed(0.12345)</literal>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <para>
+   The <function>random()</function> and <function>random_normal()</function>
+   functions listed in <xref linkend="functions-math-random-table"/> use a
+   deterministic pseudo-random number generator.
+   It is fast but not suitable for cryptographic
+   applications; see the <xref linkend="pgcrypto"/> module for a more
+   secure alternative.
+   If <function>setseed()</function> is called, the series of results of
+   subsequent calls to these functions in the current session
+   can be repeated by re-issuing <function>setseed()</function> with the same
+   argument.
+   Without any prior <function>setseed()</function> call in the same
+   session, the first call to any of these functions obtains a seed
+   from a platform-dependent source of random bits.
+  </para>
+
+  <para>
+   <xref linkend="functions-math-trig-table"/> shows the
+   available trigonometric functions.  Each of these functions comes in
+   two variants, one that measures angles in radians and one that
+   measures angles in degrees.
+  </para>
+
+   <table id="functions-math-trig-table">
+    <title>Trigonometric Functions</title>
+
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>acos</primary>
+        </indexterm>
+        <function>acos</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Inverse cosine, result in radians
+       </para>
+       <para>
+        <literal>acos(1)</literal>
+        <returnvalue>0</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>acosd</primary>
+        </indexterm>
+        <function>acosd</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Inverse cosine, result in degrees
+       </para>
+       <para>
+        <literal>acosd(0.5)</literal>
+        <returnvalue>60</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>asin</primary>
+        </indexterm>
+        <function>asin</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Inverse sine, result in radians
+       </para>
+       <para>
+        <literal>asin(1)</literal>
+        <returnvalue>1.5707963267948966</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>asind</primary>
+        </indexterm>
+        <function>asind</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Inverse sine, result in degrees
+       </para>
+       <para>
+        <literal>asind(0.5)</literal>
+        <returnvalue>30</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>atan</primary>
+        </indexterm>
+        <function>atan</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Inverse tangent, result in radians
+       </para>
+       <para>
+        <literal>atan(1)</literal>
+        <returnvalue>0.7853981633974483</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>atand</primary>
+        </indexterm>
+        <function>atand</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Inverse tangent, result in degrees
+       </para>
+       <para>
+        <literal>atand(1)</literal>
+        <returnvalue>45</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>atan2</primary>
+        </indexterm>
+        <function>atan2</function> ( <parameter>y</parameter> <type>double precision</type>,
+        <parameter>x</parameter> <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Inverse tangent of
+        <parameter>y</parameter>/<parameter>x</parameter>,
+        result in radians
+       </para>
+       <para>
+        <literal>atan2(1, 0)</literal>
+        <returnvalue>1.5707963267948966</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>atan2d</primary>
+        </indexterm>
+        <function>atan2d</function> ( <parameter>y</parameter> <type>double precision</type>,
+        <parameter>x</parameter> <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Inverse tangent of
+        <parameter>y</parameter>/<parameter>x</parameter>,
+        result in degrees
+       </para>
+       <para>
+        <literal>atan2d(1, 0)</literal>
+        <returnvalue>90</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>cos</primary>
+        </indexterm>
+        <function>cos</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Cosine, argument in radians
+       </para>
+       <para>
+        <literal>cos(0)</literal>
+        <returnvalue>1</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>cosd</primary>
+        </indexterm>
+        <function>cosd</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Cosine, argument in degrees
+       </para>
+       <para>
+        <literal>cosd(60)</literal>
+        <returnvalue>0.5</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>cot</primary>
+        </indexterm>
+        <function>cot</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Cotangent, argument in radians
+       </para>
+       <para>
+        <literal>cot(0.5)</literal>
+        <returnvalue>1.830487721712452</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>cotd</primary>
+        </indexterm>
+        <function>cotd</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Cotangent, argument in degrees
+       </para>
+       <para>
+        <literal>cotd(45)</literal>
+        <returnvalue>1</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>sin</primary>
+        </indexterm>
+        <function>sin</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Sine, argument in radians
+       </para>
+       <para>
+        <literal>sin(1)</literal>
+        <returnvalue>0.8414709848078965</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>sind</primary>
+        </indexterm>
+        <function>sind</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Sine, argument in degrees
+       </para>
+       <para>
+        <literal>sind(30)</literal>
+        <returnvalue>0.5</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>tan</primary>
+        </indexterm>
+        <function>tan</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Tangent, argument in radians
+       </para>
+       <para>
+        <literal>tan(1)</literal>
+        <returnvalue>1.5574077246549023</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>tand</primary>
+        </indexterm>
+        <function>tand</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Tangent, argument in degrees
+       </para>
+       <para>
+        <literal>tand(45)</literal>
+        <returnvalue>1</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <note>
+   <para>
+    Another way to work with angles measured in degrees is to use the unit
+    transformation functions <literal><function>radians()</function></literal>
+    and <literal><function>degrees()</function></literal> shown earlier.
+    However, using the degree-based trigonometric functions is preferred,
+    as that way avoids round-off error for special cases such
+    as <literal>sind(30)</literal>.
+   </para>
+  </note>
+
+  <para>
+   <xref linkend="functions-math-hyp-table"/> shows the
+   available hyperbolic functions.
+  </para>
+
+  <table id="functions-math-hyp-table">
+    <title>Hyperbolic Functions</title>
+
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>sinh</primary>
+        </indexterm>
+        <function>sinh</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Hyperbolic sine
+       </para>
+       <para>
+        <literal>sinh(1)</literal>
+        <returnvalue>1.1752011936438014</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>cosh</primary>
+        </indexterm>
+        <function>cosh</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Hyperbolic cosine
+       </para>
+       <para>
+        <literal>cosh(0)</literal>
+        <returnvalue>1</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>tanh</primary>
+        </indexterm>
+        <function>tanh</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Hyperbolic tangent
+       </para>
+       <para>
+        <literal>tanh(1)</literal>
+        <returnvalue>0.7615941559557649</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>asinh</primary>
+        </indexterm>
+        <function>asinh</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Inverse hyperbolic sine
+       </para>
+       <para>
+        <literal>asinh(1)</literal>
+        <returnvalue>0.881373587019543</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>acosh</primary>
+        </indexterm>
+        <function>acosh</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Inverse hyperbolic cosine
+       </para>
+       <para>
+        <literal>acosh(1)</literal>
+        <returnvalue>0</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>atanh</primary>
+        </indexterm>
+        <function>atanh</function> ( <type>double precision</type> )
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Inverse hyperbolic tangent
+       </para>
+       <para>
+        <literal>atanh(0.5)</literal>
+        <returnvalue>0.5493061443340548</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  </sect1>
diff --git a/doc/src/sgml/func/func-merge-support.sgml b/doc/src/sgml/func/func-merge-support.sgml
new file mode 100644
index 0000000000000..7f084271c13ae
--- /dev/null
+++ b/doc/src/sgml/func/func-merge-support.sgml
@@ -0,0 +1,78 @@
+ <sect1 id="functions-merge-support">
+  <title>Merge Support Functions</title>
+
+  <indexterm>
+   <primary>MERGE</primary>
+   <secondary>RETURNING</secondary>
+  </indexterm>
+
+  <para>
+   <productname>PostgreSQL</productname> includes one merge support function
+   that may be used in the <literal>RETURNING</literal> list of a
+   <xref linkend="sql-merge"/> command to identify the action taken for each
+   row; see <xref linkend="functions-merge-support-table"/>.
+  </para>
+
+  <table id="functions-merge-support-table">
+   <title>Merge Support Functions</title>
+
+   <tgroup cols="1">
+    <thead>
+     <row>
+      <entry role="func_table_entry"><para role="func_signature">
+       Function
+      </para>
+      <para>
+       Description
+      </para></entry>
+     </row>
+    </thead>
+
+    <tbody>
+     <row>
+      <entry id="merge-action" role="func_table_entry"><para role="func_signature">
+       <indexterm>
+        <primary>merge_action</primary>
+       </indexterm>
+       <function>merge_action</function> ( )
+       <returnvalue>text</returnvalue>
+      </para>
+      <para>
+       Returns the merge action command executed for the current row.  This
+       will be <literal>'INSERT'</literal>, <literal>'UPDATE'</literal>, or
+       <literal>'DELETE'</literal>.
+      </para></entry>
+     </row>
+    </tbody>
+   </tgroup>
+  </table>
+
+  <para>
+   Example:
+<screen><![CDATA[
+MERGE INTO products p
+  USING stock s ON p.product_id = s.product_id
+  WHEN MATCHED AND s.quantity > 0 THEN
+    UPDATE SET in_stock = true, quantity = s.quantity
+  WHEN MATCHED THEN
+    UPDATE SET in_stock = false, quantity = 0
+  WHEN NOT MATCHED THEN
+    INSERT (product_id, in_stock, quantity)
+      VALUES (s.product_id, true, s.quantity)
+  RETURNING merge_action(), p.*;
+
+ merge_action | product_id | in_stock | quantity
+--------------+------------+----------+----------
+ UPDATE       |       1001 | t        |       50
+ UPDATE       |       1002 | f        |        0
+ INSERT       |       1003 | t        |       10
+]]></screen>
+  </para>
+
+  <para>
+   Note that this function can only be used in the <literal>RETURNING</literal>
+   list of a <command>MERGE</command> command.  It is an error to use it in any
+   other part of a query.
+  </para>
+
+ </sect1>
diff --git a/doc/src/sgml/func/func-net.sgml b/doc/src/sgml/func/func-net.sgml
new file mode 100644
index 0000000000000..1361a44c19767
--- /dev/null
+++ b/doc/src/sgml/func/func-net.sgml
@@ -0,0 +1,592 @@
+ <sect1 id="functions-net">
+  <title>Network Address Functions and Operators</title>
+
+  <para>
+   The IP network address types, <type>cidr</type> and <type>inet</type>,
+   support the usual comparison operators shown in
+   <xref linkend="functions-comparison-op-table"/>
+   as well as the specialized operators and functions shown in
+   <xref linkend="cidr-inet-operators-table"/> and
+   <xref linkend="cidr-inet-functions-table"/>.
+  </para>
+
+  <para>
+   Any <type>cidr</type> value can be cast to <type>inet</type> implicitly;
+   therefore, the operators and functions shown below as operating on
+   <type>inet</type> also work on <type>cidr</type> values.  (Where there are
+   separate functions for <type>inet</type> and <type>cidr</type>, it is
+   because the behavior should be different for the two cases.)
+   Also, it is permitted to cast an <type>inet</type> value
+   to <type>cidr</type>.  When this is done, any bits to the right of the
+   netmask are silently zeroed to create a valid <type>cidr</type> value.
+  </para>
+
+   <table id="cidr-inet-operators-table">
+    <title>IP Address Operators</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Operator
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>inet</type> <literal>&lt;&lt;</literal> <type>inet</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is subnet strictly contained by subnet?
+        This operator, and the next four, test for subnet inclusion.  They
+        consider only the network parts of the two addresses (ignoring any
+        bits to the right of the netmasks) and determine whether one network
+        is identical to or a subnet of the other.
+       </para>
+       <para>
+        <literal>inet '192.168.1.5' &lt;&lt; inet '192.168.1/24'</literal>
+        <returnvalue>t</returnvalue>
+       </para>
+       <para>
+        <literal>inet '192.168.0.5' &lt;&lt; inet '192.168.1/24'</literal>
+        <returnvalue>f</returnvalue>
+       </para>
+       <para>
+        <literal>inet '192.168.1/24' &lt;&lt; inet '192.168.1/24'</literal>
+        <returnvalue>f</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>inet</type> <literal>&lt;&lt;=</literal> <type>inet</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is subnet contained by or equal to subnet?
+       </para>
+       <para>
+        <literal>inet '192.168.1/24' &lt;&lt;= inet '192.168.1/24'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>inet</type> <literal>&gt;&gt;</literal> <type>inet</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does subnet strictly contain subnet?
+       </para>
+       <para>
+        <literal>inet '192.168.1/24' &gt;&gt; inet '192.168.1.5'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>inet</type> <literal>&gt;&gt;=</literal> <type>inet</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does subnet contain or equal subnet?
+       </para>
+       <para>
+        <literal>inet '192.168.1/24' &gt;&gt;= inet '192.168.1/24'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>inet</type> <literal>&amp;&amp;</literal> <type>inet</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does either subnet contain or equal the other?
+       </para>
+       <para>
+        <literal>inet '192.168.1/24' &amp;&amp; inet '192.168.1.80/28'</literal>
+        <returnvalue>t</returnvalue>
+       </para>
+       <para>
+        <literal>inet '192.168.1/24' &amp;&amp; inet '192.168.2.0/28'</literal>
+        <returnvalue>f</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>~</literal> <type>inet</type>
+        <returnvalue>inet</returnvalue>
+       </para>
+       <para>
+        Computes bitwise NOT.
+       </para>
+       <para>
+        <literal>~ inet '192.168.1.6'</literal>
+        <returnvalue>63.87.254.249</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>inet</type> <literal>&amp;</literal> <type>inet</type>
+        <returnvalue>inet</returnvalue>
+       </para>
+       <para>
+        Computes bitwise AND.
+       </para>
+       <para>
+        <literal>inet '192.168.1.6' &amp; inet '0.0.0.255'</literal>
+        <returnvalue>0.0.0.6</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>inet</type> <literal>|</literal> <type>inet</type>
+        <returnvalue>inet</returnvalue>
+       </para>
+       <para>
+        Computes bitwise OR.
+       </para>
+       <para>
+        <literal>inet '192.168.1.6' | inet '0.0.0.255'</literal>
+        <returnvalue>192.168.1.255</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>inet</type> <literal>+</literal> <type>bigint</type>
+        <returnvalue>inet</returnvalue>
+       </para>
+       <para>
+        Adds an offset to an address.
+       </para>
+       <para>
+        <literal>inet '192.168.1.6' + 25</literal>
+        <returnvalue>192.168.1.31</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>bigint</type> <literal>+</literal> <type>inet</type>
+        <returnvalue>inet</returnvalue>
+       </para>
+       <para>
+        Adds an offset to an address.
+       </para>
+       <para>
+        <literal>200 + inet '::ffff:fff0:1'</literal>
+        <returnvalue>::ffff:255.240.0.201</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>inet</type> <literal>-</literal> <type>bigint</type>
+        <returnvalue>inet</returnvalue>
+       </para>
+       <para>
+        Subtracts an offset from an address.
+       </para>
+       <para>
+        <literal>inet '192.168.1.43' - 36</literal>
+        <returnvalue>192.168.1.7</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>inet</type> <literal>-</literal> <type>inet</type>
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Computes the difference of two addresses.
+       </para>
+       <para>
+        <literal>inet '192.168.1.43' - inet '192.168.1.19'</literal>
+        <returnvalue>24</returnvalue>
+       </para>
+       <para>
+        <literal>inet '::1' - inet '::ffff:1'</literal>
+        <returnvalue>-4294901760</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <table id="cidr-inet-functions-table">
+    <title>IP Address Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>abbrev</primary>
+        </indexterm>
+        <function>abbrev</function> ( <type>inet</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Creates an abbreviated display format as text.
+        (The result is the same as the <type>inet</type> output function
+        produces; it is <quote>abbreviated</quote> only in comparison to the
+        result of an explicit cast to <type>text</type>, which for historical
+        reasons will never suppress the netmask part.)
+       </para>
+       <para>
+        <literal>abbrev(inet '10.1.0.0/32')</literal>
+        <returnvalue>10.1.0.0</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>abbrev</function> ( <type>cidr</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Creates an abbreviated display format as text.
+        (The abbreviation consists of dropping all-zero octets to the right
+        of the netmask; more examples are in
+        <xref linkend="datatype-net-cidr-table"/>.)
+       </para>
+       <para>
+        <literal>abbrev(cidr '10.1.0.0/16')</literal>
+        <returnvalue>10.1/16</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>broadcast</primary>
+        </indexterm>
+        <function>broadcast</function> ( <type>inet</type> )
+        <returnvalue>inet</returnvalue>
+       </para>
+       <para>
+        Computes the broadcast address for the address's network.
+       </para>
+       <para>
+        <literal>broadcast(inet '192.168.1.5/24')</literal>
+        <returnvalue>192.168.1.255/24</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>family</primary>
+        </indexterm>
+        <function>family</function> ( <type>inet</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the address's family: <literal>4</literal> for IPv4,
+        <literal>6</literal> for IPv6.
+       </para>
+       <para>
+        <literal>family(inet '::1')</literal>
+        <returnvalue>6</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>host</primary>
+        </indexterm>
+        <function>host</function> ( <type>inet</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the IP address as text, ignoring the netmask.
+       </para>
+       <para>
+        <literal>host(inet '192.168.1.0/24')</literal>
+        <returnvalue>192.168.1.0</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>hostmask</primary>
+        </indexterm>
+        <function>hostmask</function> ( <type>inet</type> )
+        <returnvalue>inet</returnvalue>
+       </para>
+       <para>
+        Computes the host mask for the address's network.
+       </para>
+       <para>
+        <literal>hostmask(inet '192.168.23.20/30')</literal>
+        <returnvalue>0.0.0.3</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>inet_merge</primary>
+        </indexterm>
+        <function>inet_merge</function> ( <type>inet</type>, <type>inet</type> )
+        <returnvalue>cidr</returnvalue>
+       </para>
+       <para>
+        Computes the smallest network that includes both of the given networks.
+       </para>
+       <para>
+        <literal>inet_merge(inet '192.168.1.5/24', inet '192.168.2.5/24')</literal>
+        <returnvalue>192.168.0.0/22</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>inet_same_family</primary>
+        </indexterm>
+        <function>inet_same_family</function> ( <type>inet</type>, <type>inet</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Tests whether the addresses belong to the same IP family.
+       </para>
+       <para>
+        <literal>inet_same_family(inet '192.168.1.5/24', inet '::1')</literal>
+        <returnvalue>f</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>masklen</primary>
+        </indexterm>
+        <function>masklen</function> ( <type>inet</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the netmask length in bits.
+       </para>
+       <para>
+        <literal>masklen(inet '192.168.1.5/24')</literal>
+        <returnvalue>24</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>netmask</primary>
+        </indexterm>
+        <function>netmask</function> ( <type>inet</type> )
+        <returnvalue>inet</returnvalue>
+       </para>
+       <para>
+        Computes the network mask for the address's network.
+       </para>
+       <para>
+        <literal>netmask(inet '192.168.1.5/24')</literal>
+        <returnvalue>255.255.255.0</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>network</primary>
+        </indexterm>
+        <function>network</function> ( <type>inet</type> )
+        <returnvalue>cidr</returnvalue>
+       </para>
+       <para>
+        Returns the network part of the address, zeroing out
+        whatever is to the right of the netmask.
+        (This is equivalent to casting the value to <type>cidr</type>.)
+       </para>
+       <para>
+        <literal>network(inet '192.168.1.5/24')</literal>
+        <returnvalue>192.168.1.0/24</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>set_masklen</primary>
+        </indexterm>
+        <function>set_masklen</function> ( <type>inet</type>, <type>integer</type> )
+        <returnvalue>inet</returnvalue>
+       </para>
+       <para>
+        Sets the netmask length for an <type>inet</type> value.
+        The address part does not change.
+       </para>
+       <para>
+        <literal>set_masklen(inet '192.168.1.5/24', 16)</literal>
+        <returnvalue>192.168.1.5/16</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>set_masklen</function> ( <type>cidr</type>, <type>integer</type> )
+        <returnvalue>cidr</returnvalue>
+       </para>
+       <para>
+        Sets the netmask length for a <type>cidr</type> value.
+        Address bits to the right of the new netmask are set to zero.
+       </para>
+       <para>
+        <literal>set_masklen(cidr '192.168.1.0/24', 16)</literal>
+        <returnvalue>192.168.0.0/16</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>text</primary>
+        </indexterm>
+        <function>text</function> ( <type>inet</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the unabbreviated IP address and netmask length as text.
+        (This has the same result as an explicit cast to <type>text</type>.)
+       </para>
+       <para>
+        <literal>text(inet '192.168.1.5')</literal>
+        <returnvalue>192.168.1.5/32</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <tip>
+   <para>
+    The <function>abbrev</function>, <function>host</function>,
+    and <function>text</function> functions are primarily intended to offer
+    alternative display formats for IP addresses.
+   </para>
+  </tip>
+
+  <para>
+   The MAC address types, <type>macaddr</type> and <type>macaddr8</type>,
+   support the usual comparison operators shown in
+   <xref linkend="functions-comparison-op-table"/>
+   as well as the specialized functions shown in
+   <xref linkend="macaddr-functions-table"/>.
+   In addition, they support the bitwise logical operators
+   <literal>~</literal>, <literal>&amp;</literal> and <literal>|</literal>
+   (NOT, AND and OR), just as shown above for IP addresses.
+  </para>
+
+   <table id="macaddr-functions-table">
+    <title>MAC Address Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trunc</primary>
+        </indexterm>
+        <function>trunc</function> ( <type>macaddr</type> )
+        <returnvalue>macaddr</returnvalue>
+       </para>
+       <para>
+        Sets the last 3 bytes of the address to zero.  The remaining prefix
+        can be associated with a particular manufacturer (using data not
+        included in <productname>PostgreSQL</productname>).
+       </para>
+       <para>
+        <literal>trunc(macaddr '12:34:56:78:90:ab')</literal>
+        <returnvalue>12:34:56:00:00:00</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>trunc</function> ( <type>macaddr8</type> )
+        <returnvalue>macaddr8</returnvalue>
+       </para>
+       <para>
+        Sets the last 5 bytes of the address to zero.  The remaining prefix
+        can be associated with a particular manufacturer (using data not
+        included in <productname>PostgreSQL</productname>).
+       </para>
+       <para>
+        <literal>trunc(macaddr8 '12:34:56:78:90:ab:cd:ef')</literal>
+        <returnvalue>12:34:56:00:00:00:00:00</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>macaddr8_set7bit</primary>
+        </indexterm>
+        <function>macaddr8_set7bit</function> ( <type>macaddr8</type> )
+        <returnvalue>macaddr8</returnvalue>
+       </para>
+       <para>
+        Sets the 7th bit of the address to one, creating what is known as
+        modified EUI-64, for inclusion in an IPv6 address.
+       </para>
+       <para>
+        <literal>macaddr8_set7bit(macaddr8 '00:34:56:ab:cd:ef')</literal>
+        <returnvalue>02:34:56:ff:fe:ab:cd:ef</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  </sect1>
diff --git a/doc/src/sgml/func/func-range.sgml b/doc/src/sgml/func/func-range.sgml
new file mode 100644
index 0000000000000..2dc40348a57f4
--- /dev/null
+++ b/doc/src/sgml/func/func-range.sgml
@@ -0,0 +1,1053 @@
+ <sect1 id="functions-range">
+  <title>Range/Multirange Functions and Operators</title>
+
+  <para>
+   See <xref linkend="rangetypes"/> for an overview of range types.
+  </para>
+
+  <para>
+   <xref linkend="range-operators-table"/> shows the specialized operators
+   available for range types.
+   <xref linkend="multirange-operators-table"/> shows the specialized operators
+   available for multirange types.
+   In addition to those, the usual comparison operators shown in
+   <xref linkend="functions-comparison-op-table"/> are available for range
+   and multirange types.  The comparison operators order first by the range lower
+   bounds, and only if those are equal do they compare the upper bounds.  The
+   multirange operators compare each range until one is unequal. This
+   does not usually result in a useful overall ordering, but the operators are
+   provided to allow unique indexes to be constructed on ranges.
+  </para>
+
+   <table id="range-operators-table">
+    <title>Range Operators</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Operator
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>@&gt;</literal> <type>anyrange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the first range contain the second?
+       </para>
+       <para>
+        <literal>int4range(2,4) @&gt; int4range(2,3)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>@&gt;</literal> <type>anyelement</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the range contain the element?
+       </para>
+       <para>
+        <literal>'[2011-01-01,2011-03-01)'::tsrange @&gt; '2011-01-10'::timestamp</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>&lt;@</literal> <type>anyrange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the first range contained by the second?
+       </para>
+       <para>
+        <literal>int4range(2,4) &lt;@ int4range(1,7)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyelement</type> <literal>&lt;@</literal> <type>anyrange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the element contained in the range?
+       </para>
+       <para>
+        <literal>42 &lt;@ int4range(1,7)</literal>
+        <returnvalue>f</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>&amp;&amp;</literal> <type>anyrange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Do the ranges overlap, that is, have any elements in common?
+       </para>
+       <para>
+        <literal>int8range(3,7) &amp;&amp; int8range(4,12)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>&lt;&lt;</literal> <type>anyrange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the first range strictly left of the second?
+       </para>
+       <para>
+        <literal>int8range(1,10) &lt;&lt; int8range(100,110)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>&gt;&gt;</literal> <type>anyrange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the first range strictly right of the second?
+       </para>
+       <para>
+        <literal>int8range(50,60) &gt;&gt; int8range(20,30)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>&amp;&lt;</literal> <type>anyrange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the first range not extend to the right of the second?
+       </para>
+       <para>
+        <literal>int8range(1,20) &amp;&lt; int8range(18,20)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>&amp;&gt;</literal> <type>anyrange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the first range not extend to the left of the second?
+       </para>
+       <para>
+        <literal>int8range(7,20) &amp;&gt; int8range(5,10)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>-|-</literal> <type>anyrange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Are the ranges adjacent?
+       </para>
+       <para>
+        <literal>numrange(1.1,2.2) -|- numrange(2.2,3.3)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>+</literal> <type>anyrange</type>
+        <returnvalue>anyrange</returnvalue>
+       </para>
+       <para>
+        Computes the union of the ranges.  The ranges must overlap or be
+        adjacent, so that the union is a single range (but
+        see <function>range_merge()</function>).
+       </para>
+       <para>
+        <literal>numrange(5,15) + numrange(10,20)</literal>
+        <returnvalue>[5,20)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>*</literal> <type>anyrange</type>
+        <returnvalue>anyrange</returnvalue>
+       </para>
+       <para>
+        Computes the intersection of the ranges.
+       </para>
+       <para>
+        <literal>int8range(5,15) * int8range(10,20)</literal>
+        <returnvalue>[10,15)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>-</literal> <type>anyrange</type>
+        <returnvalue>anyrange</returnvalue>
+       </para>
+       <para>
+        Computes the difference of the ranges.  The second range must not be
+        contained in the first in such a way that the difference would not be
+        a single range.
+       </para>
+       <para>
+        <literal>int8range(5,15) - int8range(10,20)</literal>
+        <returnvalue>[5,10)</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <table id="multirange-operators-table">
+    <title>Multirange Operators</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Operator
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>@&gt;</literal> <type>anymultirange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the first multirange contain the second?
+       </para>
+       <para>
+        <literal>'{[2,4)}'::int4multirange @&gt; '{[2,3)}'::int4multirange</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>@&gt;</literal> <type>anyrange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the multirange contain the range?
+       </para>
+       <para>
+        <literal>'{[2,4)}'::int4multirange @&gt; int4range(2,3)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>@&gt;</literal> <type>anyelement</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the multirange contain the element?
+       </para>
+       <para>
+        <literal>'{[2011-01-01,2011-03-01)}'::tsmultirange @&gt; '2011-01-10'::timestamp</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>@&gt;</literal> <type>anymultirange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the range contain the multirange?
+       </para>
+       <para>
+        <literal>'[2,4)'::int4range @&gt; '{[2,3)}'::int4multirange</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>&lt;@</literal> <type>anymultirange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the first multirange contained by the second?
+       </para>
+       <para>
+        <literal>'{[2,4)}'::int4multirange &lt;@ '{[1,7)}'::int4multirange</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>&lt;@</literal> <type>anyrange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the multirange contained by the range?
+       </para>
+       <para>
+        <literal>'{[2,4)}'::int4multirange &lt;@ int4range(1,7)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>&lt;@</literal> <type>anymultirange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the range contained by the multirange?
+       </para>
+       <para>
+        <literal>int4range(2,4) &lt;@ '{[1,7)}'::int4multirange</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyelement</type> <literal>&lt;@</literal> <type>anymultirange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the element contained by the multirange?
+       </para>
+       <para>
+        <literal>4 &lt;@ '{[1,7)}'::int4multirange</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>&amp;&amp;</literal> <type>anymultirange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Do the multiranges overlap, that is, have any elements in common?
+       </para>
+       <para>
+        <literal>'{[3,7)}'::int8multirange &amp;&amp; '{[4,12)}'::int8multirange</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>&amp;&amp;</literal> <type>anyrange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the multirange overlap the range?
+       </para>
+       <para>
+        <literal>'{[3,7)}'::int8multirange &amp;&amp; int8range(4,12)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>&amp;&amp;</literal> <type>anymultirange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the range overlap the multirange?
+       </para>
+       <para>
+        <literal>int8range(3,7) &amp;&amp; '{[4,12)}'::int8multirange</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>&lt;&lt;</literal> <type>anymultirange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the first multirange strictly left of the second?
+       </para>
+       <para>
+        <literal>'{[1,10)}'::int8multirange &lt;&lt; '{[100,110)}'::int8multirange</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>&lt;&lt;</literal> <type>anyrange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the multirange strictly left of the range?
+       </para>
+       <para>
+        <literal>'{[1,10)}'::int8multirange &lt;&lt; int8range(100,110)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>&lt;&lt;</literal> <type>anymultirange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the range strictly left of the multirange?
+       </para>
+       <para>
+        <literal>int8range(1,10) &lt;&lt; '{[100,110)}'::int8multirange</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>&gt;&gt;</literal> <type>anymultirange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the first multirange strictly right of the second?
+       </para>
+       <para>
+        <literal>'{[50,60)}'::int8multirange &gt;&gt; '{[20,30)}'::int8multirange</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>&gt;&gt;</literal> <type>anyrange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the multirange strictly right of the range?
+       </para>
+       <para>
+        <literal>'{[50,60)}'::int8multirange &gt;&gt; int8range(20,30)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>&gt;&gt;</literal> <type>anymultirange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the range strictly right of the multirange?
+       </para>
+       <para>
+        <literal>int8range(50,60) &gt;&gt; '{[20,30)}'::int8multirange</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>&amp;&lt;</literal> <type>anymultirange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the first multirange not extend to the right of the second?
+       </para>
+       <para>
+        <literal>'{[1,20)}'::int8multirange &amp;&lt; '{[18,20)}'::int8multirange</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>&amp;&lt;</literal> <type>anyrange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the multirange not extend to the right of the range?
+       </para>
+       <para>
+        <literal>'{[1,20)}'::int8multirange &amp;&lt; int8range(18,20)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>&amp;&lt;</literal> <type>anymultirange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the range not extend to the right of the multirange?
+       </para>
+       <para>
+        <literal>int8range(1,20) &amp;&lt; '{[18,20)}'::int8multirange</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>&amp;&gt;</literal> <type>anymultirange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the first multirange not extend to the left of the second?
+       </para>
+       <para>
+        <literal>'{[7,20)}'::int8multirange &amp;&gt; '{[5,10)}'::int8multirange</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>&amp;&gt;</literal> <type>anyrange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the multirange not extend to the left of the range?
+       </para>
+       <para>
+        <literal>'{[7,20)}'::int8multirange &amp;&gt; int8range(5,10)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>&amp;&gt;</literal> <type>anymultirange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the range not extend to the left of the multirange?
+       </para>
+       <para>
+        <literal>int8range(7,20) &amp;&gt; '{[5,10)}'::int8multirange</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>-|-</literal> <type>anymultirange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Are the multiranges adjacent?
+       </para>
+       <para>
+        <literal>'{[1.1,2.2)}'::nummultirange -|- '{[2.2,3.3)}'::nummultirange</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>-|-</literal> <type>anyrange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the multirange adjacent to the range?
+       </para>
+       <para>
+        <literal>'{[1.1,2.2)}'::nummultirange -|- numrange(2.2,3.3)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anyrange</type> <literal>-|-</literal> <type>anymultirange</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the range adjacent to the multirange?
+       </para>
+       <para>
+        <literal>numrange(1.1,2.2) -|- '{[2.2,3.3)}'::nummultirange</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>+</literal> <type>anymultirange</type>
+        <returnvalue>anymultirange</returnvalue>
+       </para>
+       <para>
+        Computes the union of the multiranges.  The multiranges need not overlap
+        or be adjacent.
+       </para>
+       <para>
+        <literal>'{[5,10)}'::nummultirange + '{[15,20)}'::nummultirange</literal>
+        <returnvalue>{[5,10), [15,20)}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>*</literal> <type>anymultirange</type>
+        <returnvalue>anymultirange</returnvalue>
+       </para>
+       <para>
+        Computes the intersection of the multiranges.
+       </para>
+       <para>
+        <literal>'{[5,15)}'::int8multirange * '{[10,20)}'::int8multirange</literal>
+        <returnvalue>{[10,15)}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>anymultirange</type> <literal>-</literal> <type>anymultirange</type>
+        <returnvalue>anymultirange</returnvalue>
+       </para>
+       <para>
+        Computes the difference of the multiranges.
+       </para>
+       <para>
+        <literal>'{[5,20)}'::int8multirange - '{[10,15)}'::int8multirange</literal>
+        <returnvalue>{[5,10), [15,20)}</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <para>
+   The left-of/right-of/adjacent operators always return false when an empty
+   range or multirange is involved; that is, an empty range is not considered to
+   be either before or after any other range.
+  </para>
+
+  <para>
+   Elsewhere empty ranges and multiranges are treated as the additive identity:
+   anything unioned with an empty value is itself. Anything minus an empty
+   value is itself. An empty multirange has exactly the same points as an empty
+   range. Every range contains the empty range. Every multirange contains as many
+   empty ranges as you like.
+  </para>
+
+  <para>
+   The range union and difference operators will fail if the resulting range would
+   need to contain two disjoint sub-ranges, as such a range cannot be
+   represented. There are separate operators for union and difference that take
+   multirange parameters and return a multirange, and they do not fail even if
+   their arguments are disjoint. So if you need a union or difference operation
+   for ranges that may be disjoint, you can avoid errors by first casting your
+   ranges to multiranges.
+  </para>
+
+  <para>
+   <xref linkend="range-functions-table"/> shows the functions
+   available for use with range types.
+   <xref linkend="multirange-functions-table"/> shows the functions
+   available for use with multirange types.
+  </para>
+
+   <table id="range-functions-table">
+    <title>Range Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>lower</primary>
+        </indexterm>
+        <function>lower</function> ( <type>anyrange</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Extracts the lower bound of the range (<literal>NULL</literal> if the
+        range is empty or has no lower bound).
+       </para>
+       <para>
+        <literal>lower(numrange(1.1,2.2))</literal>
+        <returnvalue>1.1</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>upper</primary>
+        </indexterm>
+        <function>upper</function> ( <type>anyrange</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Extracts the upper bound of the range (<literal>NULL</literal> if the
+        range is empty or has no upper bound).
+       </para>
+       <para>
+        <literal>upper(numrange(1.1,2.2))</literal>
+        <returnvalue>2.2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>isempty</primary>
+        </indexterm>
+        <function>isempty</function> ( <type>anyrange</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the range empty?
+       </para>
+       <para>
+        <literal>isempty(numrange(1.1,2.2))</literal>
+        <returnvalue>f</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>lower_inc</primary>
+        </indexterm>
+        <function>lower_inc</function> ( <type>anyrange</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the range's lower bound inclusive?
+       </para>
+       <para>
+        <literal>lower_inc(numrange(1.1,2.2))</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>upper_inc</primary>
+        </indexterm>
+        <function>upper_inc</function> ( <type>anyrange</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the range's upper bound inclusive?
+       </para>
+       <para>
+        <literal>upper_inc(numrange(1.1,2.2))</literal>
+        <returnvalue>f</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>lower_inf</primary>
+        </indexterm>
+        <function>lower_inf</function> ( <type>anyrange</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the range have no lower bound?  (A lower bound of
+        <literal>-Infinity</literal> returns false.)
+       </para>
+       <para>
+        <literal>lower_inf('(,)'::daterange)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>upper_inf</primary>
+        </indexterm>
+        <function>upper_inf</function> ( <type>anyrange</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the range have no upper bound?  (An upper bound of
+        <literal>Infinity</literal> returns false.)
+       </para>
+       <para>
+        <literal>upper_inf('(,)'::daterange)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>range_merge</primary>
+        </indexterm>
+        <function>range_merge</function> ( <type>anyrange</type>, <type>anyrange</type> )
+        <returnvalue>anyrange</returnvalue>
+       </para>
+       <para>
+        Computes the smallest range that includes both of the given ranges.
+       </para>
+       <para>
+        <literal>range_merge('[1,2)'::int4range, '[3,4)'::int4range)</literal>
+        <returnvalue>[1,4)</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <table id="multirange-functions-table">
+    <title>Multirange Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>lower</primary>
+        </indexterm>
+        <function>lower</function> ( <type>anymultirange</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Extracts the lower bound of the multirange (<literal>NULL</literal> if the
+        multirange is empty or has no lower bound).
+       </para>
+       <para>
+        <literal>lower('{[1.1,2.2)}'::nummultirange)</literal>
+        <returnvalue>1.1</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>upper</primary>
+        </indexterm>
+        <function>upper</function> ( <type>anymultirange</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Extracts the upper bound of the multirange (<literal>NULL</literal> if the
+        multirange is empty or has no upper bound).
+       </para>
+       <para>
+        <literal>upper('{[1.1,2.2)}'::nummultirange)</literal>
+        <returnvalue>2.2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>isempty</primary>
+        </indexterm>
+        <function>isempty</function> ( <type>anymultirange</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the multirange empty?
+       </para>
+       <para>
+        <literal>isempty('{[1.1,2.2)}'::nummultirange)</literal>
+        <returnvalue>f</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>lower_inc</primary>
+        </indexterm>
+        <function>lower_inc</function> ( <type>anymultirange</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the multirange's lower bound inclusive?
+       </para>
+       <para>
+        <literal>lower_inc('{[1.1,2.2)}'::nummultirange)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>upper_inc</primary>
+        </indexterm>
+        <function>upper_inc</function> ( <type>anymultirange</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is the multirange's upper bound inclusive?
+       </para>
+       <para>
+        <literal>upper_inc('{[1.1,2.2)}'::nummultirange)</literal>
+        <returnvalue>f</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>lower_inf</primary>
+        </indexterm>
+        <function>lower_inf</function> ( <type>anymultirange</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the multirange have no lower bound?  (A lower bound of
+        <literal>-Infinity</literal> returns false.)
+       </para>
+       <para>
+        <literal>lower_inf('{(,)}'::datemultirange)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>upper_inf</primary>
+        </indexterm>
+        <function>upper_inf</function> ( <type>anymultirange</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does the multirange have no upper bound?  (An upper bound of
+        <literal>Infinity</literal> returns false.)
+       </para>
+       <para>
+        <literal>upper_inf('{(,)}'::datemultirange)</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>range_merge</primary>
+        </indexterm>
+        <function>range_merge</function> ( <type>anymultirange</type> )
+        <returnvalue>anyrange</returnvalue>
+       </para>
+       <para>
+        Computes the smallest range that includes the entire multirange.
+       </para>
+       <para>
+        <literal>range_merge('{[1,2), [3,4)}'::int4multirange)</literal>
+        <returnvalue>[1,4)</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>multirange (function)</primary>
+        </indexterm>
+        <function>multirange</function> ( <type>anyrange</type> )
+        <returnvalue>anymultirange</returnvalue>
+       </para>
+       <para>
+        Returns a multirange containing just the given range.
+       </para>
+       <para>
+        <literal>multirange('[1,2)'::int4range)</literal>
+        <returnvalue>{[1,2)}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>unnest</primary>
+         <secondary>for multirange</secondary>
+        </indexterm>
+        <function>unnest</function> ( <type>anymultirange</type> )
+        <returnvalue>setof anyrange</returnvalue>
+       </para>
+       <para>
+        Expands a multirange into a set of ranges in ascending order.
+       </para>
+       <para>
+        <literal>unnest('{[1,2), [3,4)}'::int4multirange)</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ [1,2)
+ [3,4)
+</programlisting>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <para>
+   The <function>lower_inc</function>, <function>upper_inc</function>,
+   <function>lower_inf</function>, and <function>upper_inf</function>
+   functions all return false for an empty range or multirange.
+  </para>
+  </sect1>
diff --git a/doc/src/sgml/func/func-sequence.sgml b/doc/src/sgml/func/func-sequence.sgml
new file mode 100644
index 0000000000000..e9f5b4e8e6b27
--- /dev/null
+++ b/doc/src/sgml/func/func-sequence.sgml
@@ -0,0 +1,195 @@
+ <sect1 id="functions-sequence">
+  <title>Sequence Manipulation Functions</title>
+
+  <indexterm>
+   <primary>sequence</primary>
+  </indexterm>
+
+  <para>
+   This section describes functions for operating on <firstterm>sequence
+   objects</firstterm>, also called sequence generators or just sequences.
+   Sequence objects are special single-row tables created with <xref
+   linkend="sql-createsequence"/>.
+   Sequence objects are commonly used to generate unique identifiers
+   for rows of a table.  The sequence functions, listed in <xref
+   linkend="functions-sequence-table"/>, provide simple, multiuser-safe
+   methods for obtaining successive sequence values from sequence
+   objects.
+  </para>
+
+   <table id="functions-sequence-table">
+    <title>Sequence Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>nextval</primary>
+        </indexterm>
+        <function>nextval</function> ( <type>regclass</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Advances the sequence object to its next value and returns that value.
+        This is done atomically: even if multiple sessions
+        execute <function>nextval</function> concurrently, each will safely
+        receive a distinct sequence value.
+        If the sequence object has been created with default parameters,
+        successive <function>nextval</function> calls will return successive
+        values beginning with 1.  Other behaviors can be obtained by using
+        appropriate parameters in the <xref linkend="sql-createsequence"/>
+        command.
+      </para>
+       <para>
+        This function requires <literal>USAGE</literal>
+        or <literal>UPDATE</literal> privilege on the sequence.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>setval</primary>
+        </indexterm>
+        <function>setval</function> ( <type>regclass</type>, <type>bigint</type> <optional>, <type>boolean</type> </optional> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Sets the sequence object's current value, and optionally
+        its <literal>is_called</literal> flag.  The two-parameter
+        form sets the sequence's <literal>last_value</literal> field to the
+        specified value and sets its <literal>is_called</literal> field to
+        <literal>true</literal>, meaning that the next
+        <function>nextval</function> will advance the sequence before
+        returning a value.  The value that will be reported
+        by <function>currval</function> is also set to the specified value.
+        In the three-parameter form, <literal>is_called</literal> can be set
+        to either <literal>true</literal>
+        or <literal>false</literal>.  <literal>true</literal> has the same
+        effect as the two-parameter form. If it is set
+        to <literal>false</literal>, the next <function>nextval</function>
+        will return exactly the specified value, and sequence advancement
+        commences with the following <function>nextval</function>.
+        Furthermore, the value reported by <function>currval</function> is not
+        changed in this case.  For example,
+<programlisting>
+SELECT setval('myseq', 42);           <lineannotation>Next <function>nextval</function> will return 43</lineannotation>
+SELECT setval('myseq', 42, true);     <lineannotation>Same as above</lineannotation>
+SELECT setval('myseq', 42, false);    <lineannotation>Next <function>nextval</function> will return 42</lineannotation>
+</programlisting>
+        The result returned by <function>setval</function> is just the value of its
+        second argument.
+       </para>
+       <para>
+        This function requires <literal>UPDATE</literal> privilege on the
+        sequence.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>currval</primary>
+        </indexterm>
+        <function>currval</function> ( <type>regclass</type> )
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Returns the value most recently obtained
+        by <function>nextval</function> for this sequence in the current
+        session.  (An error is reported if <function>nextval</function> has
+        never been called for this sequence in this session.)  Because this is
+        returning a session-local value, it gives a predictable answer whether
+        or not other sessions have executed <function>nextval</function> since
+        the current session did.
+       </para>
+       <para>
+        This function requires <literal>USAGE</literal>
+        or <literal>SELECT</literal> privilege on the sequence.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>lastval</primary>
+        </indexterm>
+        <function>lastval</function> ()
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Returns the value most recently returned by
+        <function>nextval</function> in the current session. This function is
+        identical to <function>currval</function>, except that instead
+        of taking the sequence name as an argument it refers to whichever
+        sequence <function>nextval</function> was most recently applied to
+        in the current session. It is an error to call
+        <function>lastval</function> if <function>nextval</function>
+        has not yet been called in the current session.
+       </para>
+       <para>
+        This function requires <literal>USAGE</literal>
+        or <literal>SELECT</literal> privilege on the last used sequence.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <caution>
+   <para>
+    To avoid blocking concurrent transactions that obtain numbers from
+    the same sequence, the value obtained by <function>nextval</function>
+    is not reclaimed for re-use if the calling transaction later aborts.
+    This means that transaction aborts or database crashes can result in
+    gaps in the sequence of assigned values.  That can happen without a
+    transaction abort, too.  For example an <command>INSERT</command> with
+    an <literal>ON CONFLICT</literal> clause will compute the to-be-inserted
+    tuple, including doing any required <function>nextval</function>
+    calls, before detecting any conflict that would cause it to follow
+    the <literal>ON CONFLICT</literal> rule instead.
+    Thus, <productname>PostgreSQL</productname> sequence
+    objects <emphasis>cannot be used to obtain <quote>gapless</quote>
+    sequences</emphasis>.
+   </para>
+
+   <para>
+    Likewise, sequence state changes made by <function>setval</function>
+    are immediately visible to other transactions, and are not undone if
+    the calling transaction rolls back.
+   </para>
+
+   <para>
+    If the database cluster crashes before committing a transaction
+    containing a <function>nextval</function>
+    or <function>setval</function> call, the sequence state change might
+    not have made its way to persistent storage, so that it is uncertain
+    whether the sequence will have its original or updated state after the
+    cluster restarts.  This is harmless for usage of the sequence within
+    the database, since other effects of uncommitted transactions will not
+    be visible either.  However, if you wish to use a sequence value for
+    persistent outside-the-database purposes, make sure that the
+    <function>nextval</function> call has been committed before doing so.
+   </para>
+  </caution>
+
+  <para>
+   The sequence to be operated on by a sequence function is specified by
+   a <type>regclass</type> argument, which is simply the OID of the sequence in the
+   <structname>pg_class</structname> system catalog.  You do not have to look up the
+   OID by hand, however, since the <type>regclass</type> data type's input
+   converter will do the work for you.  See <xref linkend="datatype-oid"/>
+   for details.
+  </para>
+ </sect1>
diff --git a/doc/src/sgml/func/func-srf.sgml b/doc/src/sgml/func/func-srf.sgml
new file mode 100644
index 0000000000000..eafc961c9f909
--- /dev/null
+++ b/doc/src/sgml/func/func-srf.sgml
@@ -0,0 +1,306 @@
+ <sect1 id="functions-srf">
+  <title>Set Returning Functions</title>
+
+  <indexterm zone="functions-srf">
+   <primary>set returning functions</primary>
+   <secondary>functions</secondary>
+  </indexterm>
+
+  <para>
+   This section describes functions that possibly return more than one row.
+   The most widely used functions in this class are series generating
+   functions, as detailed in <xref linkend="functions-srf-series"/> and
+   <xref linkend="functions-srf-subscripts"/>.  Other, more specialized
+   set-returning functions are described elsewhere in this manual.
+   See <xref linkend="queries-tablefunctions"/> for ways to combine multiple
+   set-returning functions.
+  </para>
+
+   <table id="functions-srf-series">
+    <title>Series Generating Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>generate_series</primary>
+        </indexterm>
+        <function>generate_series</function> ( <parameter>start</parameter> <type>integer</type>, <parameter>stop</parameter> <type>integer</type> <optional>, <parameter>step</parameter> <type>integer</type> </optional> )
+        <returnvalue>setof integer</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>generate_series</function> ( <parameter>start</parameter> <type>bigint</type>, <parameter>stop</parameter> <type>bigint</type> <optional>, <parameter>step</parameter> <type>bigint</type> </optional> )
+        <returnvalue>setof bigint</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>generate_series</function> ( <parameter>start</parameter> <type>numeric</type>, <parameter>stop</parameter> <type>numeric</type> <optional>, <parameter>step</parameter> <type>numeric</type> </optional> )
+        <returnvalue>setof numeric</returnvalue>
+       </para>
+       <para>
+        Generates a series of values from <parameter>start</parameter>
+        to <parameter>stop</parameter>, with a step size
+        of <parameter>step</parameter>.  <parameter>step</parameter>
+        defaults to 1.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>generate_series</function> ( <parameter>start</parameter> <type>timestamp</type>, <parameter>stop</parameter> <type>timestamp</type>, <parameter>step</parameter> <type>interval</type> )
+        <returnvalue>setof timestamp</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>generate_series</function> ( <parameter>start</parameter> <type>timestamp with time zone</type>, <parameter>stop</parameter> <type>timestamp with time zone</type>, <parameter>step</parameter> <type>interval</type> <optional>, <parameter>timezone</parameter> <type>text</type> </optional> )
+        <returnvalue>setof timestamp with time zone</returnvalue>
+       </para>
+       <para>
+        Generates a series of values from <parameter>start</parameter>
+        to <parameter>stop</parameter>, with a step size
+        of <parameter>step</parameter>.
+        In the timezone-aware form, times of day and daylight-savings
+        adjustments are computed according to the time zone named by
+        the <parameter>timezone</parameter> argument, or the current
+        <xref linkend="guc-timezone"/> setting if that is omitted.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <para>
+   When <parameter>step</parameter> is positive, zero rows are returned if
+   <parameter>start</parameter> is greater than <parameter>stop</parameter>.
+   Conversely, when <parameter>step</parameter> is negative, zero rows are
+   returned if <parameter>start</parameter> is less than <parameter>stop</parameter>.
+   Zero rows are also returned if any input is <literal>NULL</literal>.
+   It is an error
+   for <parameter>step</parameter> to be zero. Some examples follow:
+<programlisting>
+SELECT * FROM generate_series(2,4);
+ generate_series
+-----------------
+               2
+               3
+               4
+(3 rows)
+
+SELECT * FROM generate_series(5,1,-2);
+ generate_series
+-----------------
+               5
+               3
+               1
+(3 rows)
+
+SELECT * FROM generate_series(4,3);
+ generate_series
+-----------------
+(0 rows)
+
+SELECT generate_series(1.1, 4, 1.3);
+ generate_series
+-----------------
+             1.1
+             2.4
+             3.7
+(3 rows)
+
+-- this example relies on the date-plus-integer operator:
+SELECT current_date + s.a AS dates FROM generate_series(0,14,7) AS s(a);
+   dates
+------------
+ 2004-02-05
+ 2004-02-12
+ 2004-02-19
+(3 rows)
+
+SELECT * FROM generate_series('2008-03-01 00:00'::timestamp,
+                              '2008-03-04 12:00', '10 hours');
+   generate_series
+---------------------
+ 2008-03-01 00:00:00
+ 2008-03-01 10:00:00
+ 2008-03-01 20:00:00
+ 2008-03-02 06:00:00
+ 2008-03-02 16:00:00
+ 2008-03-03 02:00:00
+ 2008-03-03 12:00:00
+ 2008-03-03 22:00:00
+ 2008-03-04 08:00:00
+(9 rows)
+
+-- this example assumes that TimeZone is set to UTC; note the DST transition:
+SELECT * FROM generate_series('2001-10-22 00:00 -04:00'::timestamptz,
+                              '2001-11-01 00:00 -05:00'::timestamptz,
+                              '1 day'::interval, 'America/New_York');
+    generate_series
+------------------------
+ 2001-10-22 04:00:00+00
+ 2001-10-23 04:00:00+00
+ 2001-10-24 04:00:00+00
+ 2001-10-25 04:00:00+00
+ 2001-10-26 04:00:00+00
+ 2001-10-27 04:00:00+00
+ 2001-10-28 04:00:00+00
+ 2001-10-29 05:00:00+00
+ 2001-10-30 05:00:00+00
+ 2001-10-31 05:00:00+00
+ 2001-11-01 05:00:00+00
+(11 rows)
+</programlisting>
+  </para>
+
+   <table id="functions-srf-subscripts">
+    <title>Subscript Generating Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>generate_subscripts</primary>
+        </indexterm>
+        <function>generate_subscripts</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>dim</parameter> <type>integer</type> )
+        <returnvalue>setof integer</returnvalue>
+       </para>
+       <para>
+        Generates a series comprising the valid subscripts of
+        the <parameter>dim</parameter>'th dimension of the given array.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>generate_subscripts</function> ( <parameter>array</parameter> <type>anyarray</type>, <parameter>dim</parameter> <type>integer</type>,  <parameter>reverse</parameter> <type>boolean</type> )
+        <returnvalue>setof integer</returnvalue>
+       </para>
+       <para>
+        Generates a series comprising the valid subscripts of
+        the <parameter>dim</parameter>'th dimension of the given array.
+        When <parameter>reverse</parameter> is true, returns the series in
+        reverse order.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <para>
+   <function>generate_subscripts</function> is a convenience function that generates
+   the set of valid subscripts for the specified dimension of the given
+   array.
+   Zero rows are returned for arrays that do not have the requested dimension,
+   or if any input is <literal>NULL</literal>.
+   Some examples follow:
+<programlisting>
+-- basic usage:
+SELECT generate_subscripts('{NULL,1,NULL,2}'::int[], 1) AS s;
+ s
+---
+ 1
+ 2
+ 3
+ 4
+(4 rows)
+
+-- presenting an array, the subscript and the subscripted
+-- value requires a subquery:
+SELECT * FROM arrays;
+         a
+--------------------
+ {-1,-2}
+ {100,200,300}
+(2 rows)
+
+SELECT a AS array, s AS subscript, a[s] AS value
+FROM (SELECT generate_subscripts(a, 1) AS s, a FROM arrays) foo;
+     array     | subscript | value
+---------------+-----------+-------
+ {-1,-2}       |         1 |    -1
+ {-1,-2}       |         2 |    -2
+ {100,200,300} |         1 |   100
+ {100,200,300} |         2 |   200
+ {100,200,300} |         3 |   300
+(5 rows)
+
+-- unnest a 2D array:
+CREATE OR REPLACE FUNCTION unnest2(anyarray)
+RETURNS SETOF anyelement AS $$
+select $1[i][j]
+   from generate_subscripts($1,1) g1(i),
+        generate_subscripts($1,2) g2(j);
+$$ LANGUAGE sql IMMUTABLE;
+CREATE FUNCTION
+SELECT * FROM unnest2(ARRAY[[1,2],[3,4]]);
+ unnest2
+---------
+       1
+       2
+       3
+       4
+(4 rows)
+</programlisting>
+  </para>
+
+  <indexterm>
+   <primary>ordinality</primary>
+  </indexterm>
+
+  <para>
+   When a function in the <literal>FROM</literal> clause is suffixed
+   by <literal>WITH ORDINALITY</literal>, a <type>bigint</type> column is
+   appended to the function's output column(s), which starts from 1 and
+   increments by 1 for each row of the function's output.
+   This is most useful in the case of set returning
+   functions such as <function>unnest()</function>.
+
+<programlisting>
+-- set returning function WITH ORDINALITY:
+SELECT * FROM pg_ls_dir('.') WITH ORDINALITY AS t(ls,n);
+       ls        | n
+-----------------+----
+ pg_serial       |  1
+ pg_twophase     |  2
+ postmaster.opts |  3
+ pg_notify       |  4
+ postgresql.conf |  5
+ pg_tblspc       |  6
+ logfile         |  7
+ base            |  8
+ postmaster.pid  |  9
+ pg_ident.conf   | 10
+ global          | 11
+ pg_xact         | 12
+ pg_snapshots    | 13
+ pg_multixact    | 14
+ PG_VERSION      | 15
+ pg_wal          | 16
+ pg_hba.conf     | 17
+ pg_stat_tmp     | 18
+ pg_subtrans     | 19
+(19 rows)
+</programlisting>
+  </para>
+
+ </sect1>
diff --git a/doc/src/sgml/func/func-statistics.sgml b/doc/src/sgml/func/func-statistics.sgml
new file mode 100644
index 0000000000000..22dee263cc2a0
--- /dev/null
+++ b/doc/src/sgml/func/func-statistics.sgml
@@ -0,0 +1,85 @@
+  <sect1 id="functions-statistics">
+   <title>Statistics Information Functions</title>
+
+   <indexterm zone="functions-statistics">
+    <primary>function</primary>
+    <secondary>statistics</secondary>
+   </indexterm>
+
+   <para>
+    <productname>PostgreSQL</productname> provides a function to inspect complex
+    statistics defined using the <command>CREATE STATISTICS</command> command.
+   </para>
+
+  <sect2 id="functions-statistics-mcv">
+   <title>Inspecting MCV Lists</title>
+
+   <indexterm>
+    <primary>pg_mcv_list_items</primary>
+   </indexterm>
+
+<synopsis>
+<function>pg_mcv_list_items</function> ( <type>pg_mcv_list</type> ) <returnvalue>setof record</returnvalue>
+</synopsis>
+
+   <para>
+    <function>pg_mcv_list_items</function> returns a set of records describing
+    all items stored in a multi-column <acronym>MCV</acronym> list.  It
+    returns the following columns:
+
+    <informaltable>
+     <tgroup cols="3">
+      <thead>
+       <row>
+        <entry>Name</entry>
+        <entry>Type</entry>
+        <entry>Description</entry>
+       </row>
+      </thead>
+
+      <tbody>
+       <row>
+        <entry><literal>index</literal></entry>
+        <entry><type>integer</type></entry>
+        <entry>index of the item in the <acronym>MCV</acronym> list</entry>
+       </row>
+       <row>
+        <entry><literal>values</literal></entry>
+        <entry><type>text[]</type></entry>
+        <entry>values stored in the MCV item</entry>
+       </row>
+       <row>
+        <entry><literal>nulls</literal></entry>
+        <entry><type>boolean[]</type></entry>
+        <entry>flags identifying <literal>NULL</literal> values</entry>
+       </row>
+       <row>
+        <entry><literal>frequency</literal></entry>
+        <entry><type>double precision</type></entry>
+        <entry>frequency of this <acronym>MCV</acronym> item</entry>
+       </row>
+       <row>
+        <entry><literal>base_frequency</literal></entry>
+        <entry><type>double precision</type></entry>
+        <entry>base frequency of this <acronym>MCV</acronym> item</entry>
+       </row>
+      </tbody>
+     </tgroup>
+    </informaltable>
+   </para>
+
+   <para>
+    The <function>pg_mcv_list_items</function> function can be used like this:
+
+<programlisting>
+SELECT m.* FROM pg_statistic_ext join pg_statistic_ext_data on (oid = stxoid),
+                pg_mcv_list_items(stxdmcv) m WHERE stxname = 'stts';
+</programlisting>
+
+    Values of the <type>pg_mcv_list</type> type can be obtained only from the
+    <structname>pg_statistic_ext_data</structname>.<structfield>stxdmcv</structfield>
+    column.
+   </para>
+  </sect2>
+
+  </sect1>
diff --git a/doc/src/sgml/func/func-string.sgml b/doc/src/sgml/func/func-string.sgml
new file mode 100644
index 0000000000000..3eec93eb3395b
--- /dev/null
+++ b/doc/src/sgml/func/func-string.sgml
@@ -0,0 +1,1818 @@
+  <sect1 id="functions-string">
+   <title>String Functions and Operators</title>
+
+   <para>
+    This section describes functions and operators for examining and
+    manipulating string values.  Strings in this context include values
+    of the types <type>character</type>, <type>character varying</type>,
+    and <type>text</type>.  Except where noted, these functions and operators
+    are declared to accept and return type <type>text</type>.  They will
+    interchangeably accept <type>character varying</type> arguments.
+    Values of type <type>character</type> will be converted
+    to <type>text</type> before the function or operator is applied, resulting
+    in stripping any trailing spaces in the <type>character</type> value.
+   </para>
+
+   <para>
+    <acronym>SQL</acronym> defines some string functions that use
+    key words, rather than commas, to separate
+    arguments.  Details are in
+    <xref linkend="functions-string-sql"/>.
+    <productname>PostgreSQL</productname> also provides versions of these functions
+    that use the regular function invocation syntax
+    (see <xref linkend="functions-string-other"/>).
+   </para>
+
+   <note>
+    <para>
+     The string concatenation operator (<literal>||</literal>) will accept
+     non-string input, so long as at least one input is of string type, as shown
+     in <xref linkend="functions-string-sql"/>.  For other cases, inserting an
+     explicit coercion to <type>text</type> can be used to have non-string input
+     accepted.
+    </para>
+   </note>
+
+   <table id="functions-string-sql">
+    <title><acronym>SQL</acronym> String Functions and Operators</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function/Operator
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>character string</primary>
+         <secondary>concatenation</secondary>
+        </indexterm>
+        <type>text</type> <literal>||</literal> <type>text</type>
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Concatenates the two strings.
+       </para>
+       <para>
+        <literal>'Post' || 'greSQL'</literal>
+        <returnvalue>PostgreSQL</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>text</type> <literal>||</literal> <type>anynonarray</type>
+        <returnvalue>text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <type>anynonarray</type> <literal>||</literal> <type>text</type>
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts the non-string input to text, then concatenates the two
+        strings.  (The non-string input cannot be of an array type, because
+        that would create ambiguity with the array <literal>||</literal>
+        operators.  If you want to concatenate an array's text equivalent,
+        cast it to <type>text</type> explicitly.)
+       </para>
+       <para>
+        <literal>'Value: ' || 42</literal>
+        <returnvalue>Value: 42</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>btrim</primary>
+        </indexterm>
+        <function>btrim</function> ( <parameter>string</parameter> <type>text</type>
+        <optional>, <parameter>characters</parameter> <type>text</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Removes the longest string containing only characters
+        in <parameter>characters</parameter> (a space by default)
+        from the start and end of <parameter>string</parameter>.
+       </para>
+       <para>
+        <literal>btrim('xyxtrimyyx', 'xyz')</literal>
+        <returnvalue>trim</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>normalized</primary>
+        </indexterm>
+        <indexterm>
+         <primary>Unicode normalization</primary>
+        </indexterm>
+         <type>text</type> <literal>IS</literal> <optional><literal>NOT</literal></optional> <optional><parameter>form</parameter></optional> <literal>NORMALIZED</literal>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Checks whether the string is in the specified Unicode normalization
+        form.  The optional <parameter>form</parameter> key word specifies the
+        form: <literal>NFC</literal> (the default), <literal>NFD</literal>,
+        <literal>NFKC</literal>, or <literal>NFKD</literal>.  This expression can
+        only be used when the server encoding is <literal>UTF8</literal>.  Note
+        that checking for normalization using this expression is often faster
+        than normalizing possibly already normalized strings.
+       </para>
+       <para>
+        <literal>U&amp;'\0061\0308bc' IS NFD NORMALIZED</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>bit_length</primary>
+        </indexterm>
+        <function>bit_length</function> ( <type>text</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns number of bits in the string (8
+        times the <function>octet_length</function>).
+       </para>
+       <para>
+        <literal>bit_length('jose')</literal>
+        <returnvalue>32</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>char_length</primary>
+        </indexterm>
+        <indexterm>
+         <primary>character string</primary>
+         <secondary>length</secondary>
+        </indexterm>
+        <indexterm>
+         <primary>length</primary>
+         <secondary sortas="character string">of a character string</secondary>
+         <see>character string, length</see>
+        </indexterm>
+        <function>char_length</function> ( <type>text</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>character_length</primary>
+        </indexterm>
+        <function>character_length</function> ( <type>text</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns number of characters in the string.
+       </para>
+       <para>
+        <literal>char_length('jos&eacute;')</literal>
+        <returnvalue>4</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm id="function-lower">
+         <primary>lower</primary>
+        </indexterm>
+        <function>lower</function> ( <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts the string to all lower case, according to the rules of the
+        database's locale.
+       </para>
+       <para>
+        <literal>lower('TOM')</literal>
+        <returnvalue>tom</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>lpad</primary>
+        </indexterm>
+        <function>lpad</function> ( <parameter>string</parameter> <type>text</type>,
+        <parameter>length</parameter> <type>integer</type>
+        <optional>, <parameter>fill</parameter> <type>text</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Extends the <parameter>string</parameter> to length
+        <parameter>length</parameter> by prepending the characters
+        <parameter>fill</parameter> (a space by default).  If the
+        <parameter>string</parameter> is already longer than
+        <parameter>length</parameter> then it is truncated (on the right).
+       </para>
+       <para>
+        <literal>lpad('hi', 5, 'xy')</literal>
+        <returnvalue>xyxhi</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>ltrim</primary>
+        </indexterm>
+        <function>ltrim</function> ( <parameter>string</parameter> <type>text</type>
+        <optional>, <parameter>characters</parameter> <type>text</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Removes the longest string containing only characters in
+        <parameter>characters</parameter> (a space by default) from the start of
+        <parameter>string</parameter>.
+       </para>
+       <para>
+        <literal>ltrim('zzzytest', 'xyz')</literal>
+        <returnvalue>test</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm id="function-normalize">
+         <primary>normalize</primary>
+        </indexterm>
+        <indexterm>
+         <primary>Unicode normalization</primary>
+        </indexterm>
+        <function>normalize</function> ( <type>text</type>
+        <optional>, <parameter>form</parameter> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts the string to the specified Unicode
+        normalization form.  The optional <parameter>form</parameter> key word
+        specifies the form: <literal>NFC</literal> (the default),
+        <literal>NFD</literal>, <literal>NFKC</literal>, or
+        <literal>NFKD</literal>.  This function can only be used when the
+        server encoding is <literal>UTF8</literal>.
+       </para>
+       <para>
+        <literal>normalize(U&amp;'\0061\0308bc', NFC)</literal>
+        <returnvalue>U&amp;'\00E4bc'</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>octet_length</primary>
+        </indexterm>
+        <function>octet_length</function> ( <type>text</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns number of bytes in the string.
+       </para>
+       <para>
+        <literal>octet_length('jos&eacute;')</literal>
+        <returnvalue>5</returnvalue> (if server encoding is UTF8)
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>octet_length</primary>
+        </indexterm>
+        <function>octet_length</function> ( <type>character</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns number of bytes in the string.  Since this version of the
+        function accepts type <type>character</type> directly, it will not
+        strip trailing spaces.
+       </para>
+       <para>
+        <literal>octet_length('abc '::character(4))</literal>
+        <returnvalue>4</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>overlay</primary>
+        </indexterm>
+        <function>overlay</function> ( <parameter>string</parameter> <type>text</type> <literal>PLACING</literal> <parameter>newsubstring</parameter> <type>text</type> <literal>FROM</literal> <parameter>start</parameter> <type>integer</type> <optional> <literal>FOR</literal> <parameter>count</parameter> <type>integer</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Replaces the substring of <parameter>string</parameter> that starts at
+        the <parameter>start</parameter>'th character and extends
+        for <parameter>count</parameter> characters
+        with <parameter>newsubstring</parameter>.
+        If <parameter>count</parameter> is omitted, it defaults to the length
+        of <parameter>newsubstring</parameter>.
+       </para>
+       <para>
+        <literal>overlay('Txxxxas' placing 'hom' from 2 for 4)</literal>
+        <returnvalue>Thomas</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>position</primary>
+        </indexterm>
+        <function>position</function> ( <parameter>substring</parameter> <type>text</type> <literal>IN</literal> <parameter>string</parameter> <type>text</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns first starting index of the specified
+        <parameter>substring</parameter> within
+        <parameter>string</parameter>, or zero if it's not present.
+       </para>
+       <para>
+        <literal>position('om' in 'Thomas')</literal>
+        <returnvalue>3</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpad</primary>
+        </indexterm>
+        <function>rpad</function> ( <parameter>string</parameter> <type>text</type>,
+        <parameter>length</parameter> <type>integer</type>
+        <optional>, <parameter>fill</parameter> <type>text</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Extends the <parameter>string</parameter> to length
+        <parameter>length</parameter> by appending the characters
+        <parameter>fill</parameter> (a space by default).  If the
+        <parameter>string</parameter> is already longer than
+        <parameter>length</parameter> then it is truncated.
+       </para>
+       <para>
+        <literal>rpad('hi', 5, 'xy')</literal>
+        <returnvalue>hixyx</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rtrim</primary>
+        </indexterm>
+        <function>rtrim</function> ( <parameter>string</parameter> <type>text</type>
+         <optional>, <parameter>characters</parameter> <type>text</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Removes the longest string containing only characters in
+        <parameter>characters</parameter> (a space by default) from the end of
+        <parameter>string</parameter>.
+       </para>
+       <para>
+        <literal>rtrim('testxxzx', 'xyz')</literal>
+        <returnvalue>test</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>substring</primary>
+        </indexterm>
+        <function>substring</function> ( <parameter>string</parameter> <type>text</type> <optional> <literal>FROM</literal> <parameter>start</parameter> <type>integer</type> </optional> <optional> <literal>FOR</literal> <parameter>count</parameter> <type>integer</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Extracts the substring of <parameter>string</parameter> starting at
+        the <parameter>start</parameter>'th character if that is specified,
+        and stopping after <parameter>count</parameter> characters if that is
+        specified.  Provide at least one of <parameter>start</parameter>
+        and <parameter>count</parameter>.
+       </para>
+       <para>
+        <literal>substring('Thomas' from 2 for 3)</literal>
+        <returnvalue>hom</returnvalue>
+       </para>
+       <para>
+        <literal>substring('Thomas' from 3)</literal>
+        <returnvalue>omas</returnvalue>
+       </para>
+       <para>
+        <literal>substring('Thomas' for 2)</literal>
+        <returnvalue>Th</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>substring</function> ( <parameter>string</parameter> <type>text</type> <literal>FROM</literal> <parameter>pattern</parameter> <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Extracts the first substring matching POSIX regular expression; see
+        <xref linkend="functions-posix-regexp"/>.
+       </para>
+       <para>
+        <literal>substring('Thomas' from '...$')</literal>
+        <returnvalue>mas</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>substring</function> ( <parameter>string</parameter> <type>text</type> <literal>SIMILAR</literal> <parameter>pattern</parameter> <type>text</type> <literal>ESCAPE</literal> <parameter>escape</parameter> <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>substring</function> ( <parameter>string</parameter> <type>text</type> <literal>FROM</literal> <parameter>pattern</parameter> <type>text</type> <literal>FOR</literal> <parameter>escape</parameter> <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Extracts the first substring matching <acronym>SQL</acronym> regular expression;
+        see <xref linkend="functions-similarto-regexp"/>.  The first form has
+        been specified since SQL:2003; the second form was only in SQL:1999
+        and should be considered obsolete.
+       </para>
+       <para>
+        <literal>substring('Thomas' similar '%#"o_a#"_' escape '#')</literal>
+        <returnvalue>oma</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>trim</primary>
+        </indexterm>
+        <function>trim</function> ( <optional> <literal>LEADING</literal> | <literal>TRAILING</literal> | <literal>BOTH</literal> </optional>
+        <optional> <parameter>characters</parameter> <type>text</type> </optional> <literal>FROM</literal>
+        <parameter>string</parameter> <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Removes the longest string containing only characters in
+        <parameter>characters</parameter> (a space by default) from the
+        start, end, or both ends (<literal>BOTH</literal> is the default)
+        of <parameter>string</parameter>.
+       </para>
+       <para>
+        <literal>trim(both 'xyz' from 'yxTomxx')</literal>
+        <returnvalue>Tom</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>trim</function> ( <optional> <literal>LEADING</literal> | <literal>TRAILING</literal> | <literal>BOTH</literal> </optional> <optional> <literal>FROM</literal> </optional>
+        <parameter>string</parameter> <type>text</type> <optional>,
+        <parameter>characters</parameter> <type>text</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        This is a non-standard syntax for <function>trim()</function>.
+       </para>
+       <para>
+        <literal>trim(both from 'yxTomxx', 'xyz')</literal>
+        <returnvalue>Tom</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>unicode_assigned</primary>
+        </indexterm>
+        <function>unicode_assigned</function> ( <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Returns <literal>true</literal> if all characters in the string are
+        assigned Unicode codepoints; <literal>false</literal> otherwise. This
+        function can only be used when the server encoding is
+        <literal>UTF8</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>upper</primary>
+        </indexterm>
+        <function>upper</function> ( <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts the string to all upper case, according to the rules of the
+        database's locale.
+       </para>
+       <para>
+        <literal>upper('tom')</literal>
+        <returnvalue>TOM</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    Additional string manipulation functions and operators are available
+    and are listed in <xref linkend="functions-string-other"/>.  (Some of
+    these are used internally to implement
+    the <acronym>SQL</acronym>-standard string functions listed in
+    <xref linkend="functions-string-sql"/>.)
+    There are also pattern-matching operators, which are described in
+    <xref linkend="functions-matching"/>, and operators for full-text
+    search, which are described in <xref linkend="textsearch"/>.
+   </para>
+
+   <table id="functions-string-other">
+    <title>Other String Functions and Operators</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function/Operator
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>character string</primary>
+         <secondary>prefix test</secondary>
+        </indexterm>
+        <type>text</type> <literal>^@</literal> <type>text</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Returns true if the first string starts with the second string
+        (equivalent to the <function>starts_with()</function> function).
+       </para>
+       <para>
+        <literal>'alphabet' ^@ 'alph'</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>ascii</primary>
+        </indexterm>
+        <function>ascii</function> ( <type>text</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the numeric code of the first character of the argument.
+        In <acronym>UTF8</acronym> encoding, returns the Unicode code point
+        of the character.  In other multibyte encodings, the argument must
+        be an <acronym>ASCII</acronym> character.
+       </para>
+       <para>
+        <literal>ascii('x')</literal>
+        <returnvalue>120</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>chr</primary>
+        </indexterm>
+        <function>chr</function> ( <type>integer</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the character with the given code. In <acronym>UTF8</acronym>
+        encoding the argument is treated as a Unicode code point. In other
+        multibyte encodings the argument must designate
+        an <acronym>ASCII</acronym> character.  <literal>chr(0)</literal> is
+        disallowed because text data types cannot store that character.
+      </para>
+      <para>
+        <literal>chr(65)</literal>
+        <returnvalue>A</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>concat</primary>
+        </indexterm>
+        <function>concat</function> ( <parameter>val1</parameter> <type>"any"</type>
+         <optional>, <parameter>val2</parameter> <type>"any"</type> <optional>, ...</optional> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Concatenates the text representations of all the arguments.
+        NULL arguments are ignored.
+       </para>
+       <para>
+        <literal>concat('abcde', 2, NULL, 22)</literal>
+        <returnvalue>abcde222</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>concat_ws</primary>
+        </indexterm>
+        <function>concat_ws</function> ( <parameter>sep</parameter> <type>text</type>,
+        <parameter>val1</parameter> <type>"any"</type>
+        <optional>, <parameter>val2</parameter> <type>"any"</type> <optional>, ...</optional> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Concatenates all but the first argument, with separators. The first
+        argument is used as the separator string, and should not be NULL.
+        Other NULL arguments are ignored.
+       </para>
+       <para>
+        <literal>concat_ws(',', 'abcde', 2, NULL, 22)</literal>
+        <returnvalue>abcde,2,22</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>format</primary>
+        </indexterm>
+        <function>format</function> ( <parameter>formatstr</parameter> <type>text</type>
+        <optional>, <parameter>formatarg</parameter> <type>"any"</type> <optional>, ...</optional> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+         Formats arguments according to a format string;
+         see <xref linkend="functions-string-format"/>.
+         This function is similar to the C function <function>sprintf</function>.
+       </para>
+       <para>
+        <literal>format('Hello %s, %1$s', 'World')</literal>
+        <returnvalue>Hello World, World</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>initcap</primary>
+        </indexterm>
+        <function>initcap</function> ( <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts the first letter of each word to upper case and the
+        rest to lower case. When using the <literal>libc</literal> locale
+        provider, words are sequences of alphanumeric characters separated
+        by non-alphanumeric characters; when using the ICU locale provider,
+        words are separated according to
+        <ulink url="https://www.unicode.org/reports/tr29/#Word_Boundaries">Unicode Standard Annex #29</ulink>.
+       </para>
+       <para>
+        <literal>initcap('hi THOMAS')</literal>
+        <returnvalue>Hi Thomas</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>casefold</primary>
+        </indexterm>
+        <function>casefold</function> ( <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Performs case folding of the input string according to the collation.
+        Case folding is similar to case conversion, but the purpose of case
+        folding is to facilitate case-insensitive matching of strings,
+        whereas the purpose of case conversion is to convert to a particular
+        cased form.  This function can only be used when the server encoding
+        is <literal>UTF8</literal>.
+       </para>
+       <para>
+        Ordinarily, case folding simply converts to lowercase, but there may
+        be exceptions depending on the collation.  For instance, some
+        characters have more than two lowercase variants, or fold to uppercase.
+       </para>
+       <para>
+        Case folding may change the length of the string.  For instance, in
+        the <literal>PG_UNICODE_FAST</literal> collation, <literal>ß</literal>
+        (U+00DF) folds to <literal>ss</literal>.
+       </para>
+       <para>
+        <function>casefold</function> can be used for Unicode Default Caseless
+        Matching.  It does not always preserve the normalized form of the
+        input string (see <xref linkend="function-normalize"/>).
+       </para>
+       <para>
+        The <literal>libc</literal> provider doesn't support case folding, so
+        <function>casefold</function> is identical to <xref
+        linkend="function-lower"/>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>left</primary>
+        </indexterm>
+        <function>left</function> ( <parameter>string</parameter> <type>text</type>,
+        <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns first <parameter>n</parameter> characters in the
+        string, or when <parameter>n</parameter> is negative, returns
+        all but last |<parameter>n</parameter>| characters.
+       </para>
+       <para>
+        <literal>left('abcde', 2)</literal>
+        <returnvalue>ab</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>length</primary>
+        </indexterm>
+        <function>length</function> ( <type>text</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the number of characters in the string.
+       </para>
+       <para>
+        <literal>length('jose')</literal>
+        <returnvalue>4</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>md5</primary>
+        </indexterm>
+        <function>md5</function> ( <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Computes the MD5 <link linkend="functions-hash-note">hash</link> of
+        the argument, with the result written in hexadecimal.
+       </para>
+       <para>
+        <literal>md5('abc')</literal>
+        <returnvalue>900150983cd24fb0&zwsp;d6963f7d28e17f72</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>parse_ident</primary>
+        </indexterm>
+        <function>parse_ident</function> ( <parameter>qualified_identifier</parameter> <type>text</type>
+        <optional>, <parameter>strict_mode</parameter> <type>boolean</type> <literal>DEFAULT</literal> <literal>true</literal> </optional> )
+        <returnvalue>text[]</returnvalue>
+       </para>
+       <para>
+        Splits <parameter>qualified_identifier</parameter> into an array of
+        identifiers, removing any quoting of individual identifiers.  By
+        default, extra characters after the last identifier are considered an
+        error; but if the second parameter is <literal>false</literal>, then such
+        extra characters are ignored. (This behavior is useful for parsing
+        names for objects like functions.) Note that this function does not
+        truncate over-length identifiers. If you want truncation you can cast
+        the result to <type>name[]</type>.
+       </para>
+       <para>
+        <literal>parse_ident('"SomeSchema".someTable')</literal>
+        <returnvalue>{SomeSchema,sometable}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>pg_client_encoding</primary>
+        </indexterm>
+        <function>pg_client_encoding</function> ( )
+        <returnvalue>name</returnvalue>
+       </para>
+       <para>
+        Returns current client encoding name.
+       </para>
+       <para>
+        <literal>pg_client_encoding()</literal>
+        <returnvalue>UTF8</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>quote_ident</primary>
+        </indexterm>
+        <function>quote_ident</function> ( <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the given string suitably quoted to be used as an identifier
+        in an <acronym>SQL</acronym> statement string.
+        Quotes are added only if necessary (i.e., if the string contains
+        non-identifier characters or would be case-folded).
+        Embedded quotes are properly doubled.
+        See also <xref linkend="plpgsql-quote-literal-example"/>.
+       </para>
+       <para>
+        <literal>quote_ident('Foo bar')</literal>
+        <returnvalue>"Foo bar"</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>quote_literal</primary>
+        </indexterm>
+        <function>quote_literal</function> ( <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the given string suitably quoted to be used as a string literal
+        in an <acronym>SQL</acronym> statement string.
+        Embedded single-quotes and backslashes are properly doubled.
+        Note that <function>quote_literal</function> returns null on null
+        input; if the argument might be null,
+        <function>quote_nullable</function> is often more suitable.
+        See also <xref linkend="plpgsql-quote-literal-example"/>.
+       </para>
+       <para>
+        <literal>quote_literal(E'O\'Reilly')</literal>
+        <returnvalue>'O''Reilly'</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>quote_literal</function> ( <type>anyelement</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts the given value to text and then quotes it as a literal.
+        Embedded single-quotes and backslashes are properly doubled.
+       </para>
+       <para>
+        <literal>quote_literal(42.5)</literal>
+        <returnvalue>'42.5'</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>quote_nullable</primary>
+        </indexterm>
+        <function>quote_nullable</function> ( <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the given string suitably quoted to be used as a string literal
+        in an <acronym>SQL</acronym> statement string; or, if the argument
+        is null, returns <literal>NULL</literal>.
+        Embedded single-quotes and backslashes are properly doubled.
+        See also <xref linkend="plpgsql-quote-literal-example"/>.
+       </para>
+       <para>
+        <literal>quote_nullable(NULL)</literal>
+        <returnvalue>NULL</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>quote_nullable</function> ( <type>anyelement</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts the given value to text and then quotes it as a literal;
+        or, if the argument is null, returns <literal>NULL</literal>.
+        Embedded single-quotes and backslashes are properly doubled.
+       </para>
+       <para>
+        <literal>quote_nullable(42.5)</literal>
+        <returnvalue>'42.5'</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regexp_count</primary>
+        </indexterm>
+        <function>regexp_count</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type>
+         <optional>, <parameter>start</parameter> <type>integer</type>
+         <optional>, <parameter>flags</parameter> <type>text</type> </optional> </optional> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the number of times the POSIX regular
+        expression <parameter>pattern</parameter> matches in
+        the <parameter>string</parameter>; see
+        <xref linkend="functions-posix-regexp"/>.
+       </para>
+       <para>
+        <literal>regexp_count('123456789012', '\d\d\d', 2)</literal>
+        <returnvalue>3</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regexp_instr</primary>
+        </indexterm>
+        <function>regexp_instr</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type>
+         <optional>, <parameter>start</parameter> <type>integer</type>
+         <optional>, <parameter>N</parameter> <type>integer</type>
+         <optional>, <parameter>endoption</parameter> <type>integer</type>
+         <optional>, <parameter>flags</parameter> <type>text</type>
+         <optional>, <parameter>subexpr</parameter> <type>integer</type> </optional> </optional> </optional> </optional> </optional> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the position within <parameter>string</parameter> where
+        the <parameter>N</parameter>'th match of the POSIX regular
+        expression <parameter>pattern</parameter> occurs, or zero if there is
+        no such match; see <xref linkend="functions-posix-regexp"/>.
+       </para>
+       <para>
+        <literal>regexp_instr('ABCDEF', 'c(.)(..)', 1, 1, 0, 'i')</literal>
+        <returnvalue>3</returnvalue>
+       </para>
+       <para>
+        <literal>regexp_instr('ABCDEF', 'c(.)(..)', 1, 1, 0, 'i', 2)</literal>
+        <returnvalue>5</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regexp_like</primary>
+        </indexterm>
+        <function>regexp_like</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type>
+         <optional>, <parameter>flags</parameter> <type>text</type> </optional> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Checks whether a match of the POSIX regular
+        expression <parameter>pattern</parameter> occurs
+        within <parameter>string</parameter>; see
+        <xref linkend="functions-posix-regexp"/>.
+       </para>
+       <para>
+        <literal>regexp_like('Hello World', 'world$', 'i')</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regexp_match</primary>
+        </indexterm>
+        <function>regexp_match</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type> <optional>, <parameter>flags</parameter> <type>text</type> </optional> )
+        <returnvalue>text[]</returnvalue>
+       </para>
+       <para>
+        Returns substrings within the first match of the POSIX regular
+        expression <parameter>pattern</parameter> to
+        the <parameter>string</parameter>; see
+        <xref linkend="functions-posix-regexp"/>.
+       </para>
+       <para>
+        <literal>regexp_match('foobarbequebaz', '(bar)(beque)')</literal>
+        <returnvalue>{bar,beque}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regexp_matches</primary>
+        </indexterm>
+        <function>regexp_matches</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type> <optional>, <parameter>flags</parameter> <type>text</type> </optional> )
+        <returnvalue>setof text[]</returnvalue>
+       </para>
+       <para>
+        Returns substrings within the first match of the POSIX regular
+        expression <parameter>pattern</parameter> to
+        the <parameter>string</parameter>, or substrings within all
+        such matches if the <literal>g</literal> flag is used;
+        see <xref linkend="functions-posix-regexp"/>.
+       </para>
+       <para>
+        <literal>regexp_matches('foobarbequebaz', 'ba.', 'g')</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ {bar}
+ {baz}
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regexp_replace</primary>
+        </indexterm>
+        <function>regexp_replace</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type>, <parameter>replacement</parameter> <type>text</type>
+         <optional>, <parameter>flags</parameter> <type>text</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Replaces the substring that is the first match to the POSIX
+        regular expression <parameter>pattern</parameter>, or all such
+        matches if the <literal>g</literal> flag is used; see
+        <xref linkend="functions-posix-regexp"/>.
+       </para>
+       <para>
+        <literal>regexp_replace('Thomas', '.[mN]a.', 'M')</literal>
+        <returnvalue>ThM</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>regexp_replace</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type>, <parameter>replacement</parameter> <type>text</type>,
+         <parameter>start</parameter> <type>integer</type>
+         <optional>, <parameter>N</parameter> <type>integer</type>
+         <optional>, <parameter>flags</parameter> <type>text</type> </optional> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Replaces the substring that is the <parameter>N</parameter>'th
+        match to the POSIX regular expression <parameter>pattern</parameter>,
+        or all such matches if <parameter>N</parameter> is zero, with the
+        search beginning at the <parameter>start</parameter>'th character
+        of <parameter>string</parameter>.  If <parameter>N</parameter> is
+        omitted, it defaults to 1.  See
+        <xref linkend="functions-posix-regexp"/>.
+       </para>
+       <para>
+        <literal>regexp_replace('Thomas', '.', 'X', 3, 2)</literal>
+        <returnvalue>ThoXas</returnvalue>
+       </para>
+       <para>
+        <literal>regexp_replace(string=>'hello world', pattern=>'l', replacement=>'XX', start=>1, "N"=>2)</literal>
+        <returnvalue>helXXo world</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regexp_split_to_array</primary>
+        </indexterm>
+        <function>regexp_split_to_array</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type> <optional>, <parameter>flags</parameter> <type>text</type> </optional> )
+        <returnvalue>text[]</returnvalue>
+       </para>
+       <para>
+        Splits <parameter>string</parameter> using a POSIX regular
+        expression as the delimiter, producing an array of results; see
+        <xref linkend="functions-posix-regexp"/>.
+       </para>
+       <para>
+        <literal>regexp_split_to_array('hello world', '\s+')</literal>
+        <returnvalue>{hello,world}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regexp_split_to_table</primary>
+        </indexterm>
+        <function>regexp_split_to_table</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type> <optional>, <parameter>flags</parameter> <type>text</type> </optional> )
+        <returnvalue>setof text</returnvalue>
+       </para>
+       <para>
+        Splits <parameter>string</parameter> using a POSIX regular
+        expression as the delimiter, producing a set of results; see
+        <xref linkend="functions-posix-regexp"/>.
+       </para>
+       <para>
+        <literal>regexp_split_to_table('hello world', '\s+')</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ hello
+ world
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>regexp_substr</primary>
+        </indexterm>
+        <function>regexp_substr</function> ( <parameter>string</parameter> <type>text</type>, <parameter>pattern</parameter> <type>text</type>
+         <optional>, <parameter>start</parameter> <type>integer</type>
+         <optional>, <parameter>N</parameter> <type>integer</type>
+         <optional>, <parameter>flags</parameter> <type>text</type>
+         <optional>, <parameter>subexpr</parameter> <type>integer</type> </optional> </optional> </optional> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns the substring within <parameter>string</parameter> that
+        matches the <parameter>N</parameter>'th occurrence of the POSIX
+        regular expression <parameter>pattern</parameter>,
+        or <literal>NULL</literal> if there is no such match; see
+        <xref linkend="functions-posix-regexp"/>.
+       </para>
+       <para>
+        <literal>regexp_substr('ABCDEF', 'c(.)(..)', 1, 1, 'i')</literal>
+        <returnvalue>CDEF</returnvalue>
+       </para>
+       <para>
+        <literal>regexp_substr('ABCDEF', 'c(.)(..)', 1, 1, 'i', 2)</literal>
+        <returnvalue>EF</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>repeat</primary>
+        </indexterm>
+        <function>repeat</function> ( <parameter>string</parameter> <type>text</type>, <parameter>number</parameter> <type>integer</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Repeats <parameter>string</parameter> the specified
+        <parameter>number</parameter> of times.
+       </para>
+       <para>
+        <literal>repeat('Pg', 4)</literal>
+        <returnvalue>PgPgPgPg</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>replace</primary>
+        </indexterm>
+        <function>replace</function> ( <parameter>string</parameter> <type>text</type>,
+        <parameter>from</parameter> <type>text</type>,
+        <parameter>to</parameter> <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Replaces all occurrences in <parameter>string</parameter> of
+        substring <parameter>from</parameter> with
+        substring <parameter>to</parameter>.
+       </para>
+       <para>
+        <literal>replace('abcdefabcdef', 'cd', 'XX')</literal>
+        <returnvalue>abXXefabXXef</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>reverse</primary>
+        </indexterm>
+        <function>reverse</function> ( <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Reverses the order of the characters in the string.
+       </para>
+       <para>
+        <literal>reverse('abcde')</literal>
+        <returnvalue>edcba</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>right</primary>
+        </indexterm>
+        <function>right</function> ( <parameter>string</parameter> <type>text</type>,
+         <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Returns last <parameter>n</parameter> characters in the string,
+        or when <parameter>n</parameter> is negative, returns all but
+        first |<parameter>n</parameter>| characters.
+       </para>
+       <para>
+        <literal>right('abcde', 2)</literal>
+        <returnvalue>de</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>split_part</primary>
+        </indexterm>
+        <function>split_part</function> ( <parameter>string</parameter> <type>text</type>,
+        <parameter>delimiter</parameter> <type>text</type>,
+        <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Splits <parameter>string</parameter> at occurrences
+        of <parameter>delimiter</parameter> and returns
+        the <parameter>n</parameter>'th field (counting from one),
+        or when <parameter>n</parameter> is negative, returns
+        the |<parameter>n</parameter>|'th-from-last field.
+       </para>
+       <para>
+        <literal>split_part('abc~@~def~@~ghi', '~@~', 2)</literal>
+        <returnvalue>def</returnvalue>
+       </para>
+       <para>
+        <literal>split_part('abc,def,ghi,jkl', ',', -2)</literal>
+        <returnvalue>ghi</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>starts_with</primary>
+        </indexterm>
+        <function>starts_with</function> ( <parameter>string</parameter> <type>text</type>, <parameter>prefix</parameter> <type>text</type> )
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Returns true if <parameter>string</parameter> starts
+        with <parameter>prefix</parameter>.
+       </para>
+       <para>
+        <literal>starts_with('alphabet', 'alph')</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm id="function-string-to-array">
+         <primary>string_to_array</primary>
+        </indexterm>
+        <function>string_to_array</function> ( <parameter>string</parameter> <type>text</type>, <parameter>delimiter</parameter> <type>text</type> <optional>, <parameter>null_string</parameter> <type>text</type> </optional> )
+        <returnvalue>text[]</returnvalue>
+       </para>
+       <para>
+        Splits the <parameter>string</parameter> at occurrences
+        of <parameter>delimiter</parameter> and forms the resulting fields
+        into a <type>text</type> array.
+        If <parameter>delimiter</parameter> is <literal>NULL</literal>,
+        each character in the <parameter>string</parameter> will become a
+        separate element in the array.
+        If <parameter>delimiter</parameter> is an empty string, then
+        the <parameter>string</parameter> is treated as a single field.
+        If <parameter>null_string</parameter> is supplied and is
+        not <literal>NULL</literal>, fields matching that string are
+        replaced by <literal>NULL</literal>.
+        See also <link linkend="function-array-to-string"><function>array_to_string</function></link>.
+       </para>
+       <para>
+        <literal>string_to_array('xx~~yy~~zz', '~~', 'yy')</literal>
+        <returnvalue>{xx,NULL,zz}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>string_to_table</primary>
+        </indexterm>
+        <function>string_to_table</function> ( <parameter>string</parameter> <type>text</type>, <parameter>delimiter</parameter> <type>text</type> <optional>, <parameter>null_string</parameter> <type>text</type> </optional> )
+        <returnvalue>setof text</returnvalue>
+       </para>
+       <para>
+        Splits the <parameter>string</parameter> at occurrences
+        of <parameter>delimiter</parameter> and returns the resulting fields
+        as a set of <type>text</type> rows.
+        If <parameter>delimiter</parameter> is <literal>NULL</literal>,
+        each character in the <parameter>string</parameter> will become a
+        separate row of the result.
+        If <parameter>delimiter</parameter> is an empty string, then
+        the <parameter>string</parameter> is treated as a single field.
+        If <parameter>null_string</parameter> is supplied and is
+        not <literal>NULL</literal>, fields matching that string are
+        replaced by <literal>NULL</literal>.
+       </para>
+       <para>
+        <literal>string_to_table('xx~^~yy~^~zz', '~^~', 'yy')</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ xx
+ NULL
+ zz
+</programlisting>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>strpos</primary>
+        </indexterm>
+        <function>strpos</function> ( <parameter>string</parameter> <type>text</type>, <parameter>substring</parameter> <type>text</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns first starting index of the specified <parameter>substring</parameter>
+        within <parameter>string</parameter>, or zero if it's not present.
+        (Same as <literal>position(<parameter>substring</parameter> in
+        <parameter>string</parameter>)</literal>, but note the reversed
+        argument order.)
+       </para>
+       <para>
+        <literal>strpos('high', 'ig')</literal>
+        <returnvalue>2</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>substr</primary>
+        </indexterm>
+        <function>substr</function> ( <parameter>string</parameter> <type>text</type>, <parameter>start</parameter> <type>integer</type> <optional>, <parameter>count</parameter> <type>integer</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Extracts the substring of <parameter>string</parameter> starting at
+        the <parameter>start</parameter>'th character,
+        and extending for <parameter>count</parameter> characters if that is
+        specified.  (Same
+        as <literal>substring(<parameter>string</parameter>
+        from <parameter>start</parameter>
+        for <parameter>count</parameter>)</literal>.)
+       </para>
+       <para>
+        <literal>substr('alphabet', 3)</literal>
+        <returnvalue>phabet</returnvalue>
+       </para>
+       <para>
+        <literal>substr('alphabet', 3, 2)</literal>
+        <returnvalue>ph</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_ascii</primary>
+        </indexterm>
+        <function>to_ascii</function> ( <parameter>string</parameter> <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>to_ascii</function> ( <parameter>string</parameter> <type>text</type>,
+        <parameter>encoding</parameter> <type>name</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>to_ascii</function> ( <parameter>string</parameter> <type>text</type>,
+        <parameter>encoding</parameter> <type>integer</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts <parameter>string</parameter> to <acronym>ASCII</acronym>
+        from another encoding, which may be identified by name or number.
+        If <parameter>encoding</parameter> is omitted the database encoding
+        is assumed (which in practice is the only useful case).
+        The conversion consists primarily of dropping accents.
+        Conversion is only supported
+        from <literal>LATIN1</literal>, <literal>LATIN2</literal>,
+        <literal>LATIN9</literal>, and <literal>WIN1250</literal> encodings.
+        (See the <xref linkend="unaccent"/> module for another, more flexible
+        solution.)
+       </para>
+       <para>
+        <literal>to_ascii('Kar&eacute;l')</literal>
+        <returnvalue>Karel</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_bin</primary>
+        </indexterm>
+        <function>to_bin</function> ( <type>integer</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>to_bin</function> ( <type>bigint</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts the number to its equivalent two's complement binary
+        representation.
+       </para>
+       <para>
+        <literal>to_bin(2147483647)</literal>
+        <returnvalue>1111111111111111111111111111111</returnvalue>
+       </para>
+       <para>
+        <literal>to_bin(-1234)</literal>
+        <returnvalue>11111111111111111111101100101110</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_hex</primary>
+        </indexterm>
+        <function>to_hex</function> ( <type>integer</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>to_hex</function> ( <type>bigint</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts the number to its equivalent two's complement hexadecimal
+        representation.
+       </para>
+       <para>
+        <literal>to_hex(2147483647)</literal>
+        <returnvalue>7fffffff</returnvalue>
+       </para>
+       <para>
+        <literal>to_hex(-1234)</literal>
+        <returnvalue>fffffb2e</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_oct</primary>
+        </indexterm>
+        <function>to_oct</function> ( <type>integer</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>to_oct</function> ( <type>bigint</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Converts the number to its equivalent two's complement octal
+        representation.
+       </para>
+       <para>
+        <literal>to_oct(2147483647)</literal>
+        <returnvalue>17777777777</returnvalue>
+       </para>
+       <para>
+        <literal>to_oct(-1234)</literal>
+        <returnvalue>37777775456</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>translate</primary>
+        </indexterm>
+        <function>translate</function> ( <parameter>string</parameter> <type>text</type>,
+        <parameter>from</parameter> <type>text</type>,
+        <parameter>to</parameter> <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Replaces each character in <parameter>string</parameter> that
+        matches a character in the <parameter>from</parameter> set with the
+        corresponding character in the <parameter>to</parameter>
+        set. If <parameter>from</parameter> is longer than
+        <parameter>to</parameter>, occurrences of the extra characters in
+        <parameter>from</parameter> are deleted.
+       </para>
+       <para>
+        <literal>translate('12345', '143', 'ax')</literal>
+        <returnvalue>a2x5</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>unistr</primary>
+        </indexterm>
+        <function>unistr</function> ( <type>text</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Evaluate escaped Unicode characters in the argument.  Unicode characters
+        can be specified as
+        <literal>\<replaceable>XXXX</replaceable></literal> (4 hexadecimal
+        digits), <literal>\+<replaceable>XXXXXX</replaceable></literal> (6
+        hexadecimal digits),
+        <literal>\u<replaceable>XXXX</replaceable></literal> (4 hexadecimal
+        digits), or <literal>\U<replaceable>XXXXXXXX</replaceable></literal>
+        (8 hexadecimal digits).  To specify a backslash, write two
+        backslashes.  All other characters are taken literally.
+       </para>
+
+       <para>
+        If the server encoding is not UTF-8, the Unicode code point identified
+        by one of these escape sequences is converted to the actual server
+        encoding; an error is reported if that's not possible.
+       </para>
+
+       <para>
+        This function provides a (non-standard) alternative to string
+        constants with Unicode escapes (see <xref
+        linkend="sql-syntax-strings-uescape"/>).
+       </para>
+
+       <para>
+        <literal>unistr('d\0061t\+000061')</literal>
+        <returnvalue>data</returnvalue>
+       </para>
+       <para>
+        <literal>unistr('d\u0061t\U00000061')</literal>
+        <returnvalue>data</returnvalue>
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+    The <function>concat</function>, <function>concat_ws</function> and
+    <function>format</function> functions are variadic, so it is possible to
+    pass the values to be concatenated or formatted as an array marked with
+    the <literal>VARIADIC</literal> keyword (see <xref
+    linkend="xfunc-sql-variadic-functions"/>).  The array's elements are
+    treated as if they were separate ordinary arguments to the function.
+    If the variadic array argument is NULL, <function>concat</function>
+    and <function>concat_ws</function> return NULL, but
+    <function>format</function> treats a NULL as a zero-element array.
+   </para>
+
+   <para>
+    See also the aggregate function <function>string_agg</function> in
+    <xref linkend="functions-aggregate"/>, and the functions for
+    converting between strings and the <type>bytea</type> type in
+    <xref linkend="functions-binarystring-conversions"/>.
+   </para>
+
+   <sect2 id="functions-string-format">
+    <title><function>format</function></title>
+
+    <indexterm>
+     <primary>format</primary>
+    </indexterm>
+
+    <para>
+     The function <function>format</function> produces output formatted according to
+     a format string, in a style similar to the C function
+     <function>sprintf</function>.
+    </para>
+
+    <para>
+<synopsis>
+<function>format</function>(<parameter>formatstr</parameter> <type>text</type> <optional>, <parameter>formatarg</parameter> <type>"any"</type> <optional>, ...</optional> </optional>)
+</synopsis>
+     <parameter>formatstr</parameter> is a format string that specifies how the
+     result should be formatted.  Text in the format string is copied
+     directly to the result, except where <firstterm>format specifiers</firstterm> are
+     used.  Format specifiers act as placeholders in the string, defining how
+     subsequent function arguments should be formatted and inserted into the
+     result.  Each <parameter>formatarg</parameter> argument is converted to text
+     according to the usual output rules for its data type, and then formatted
+     and inserted into the result string according to the format specifier(s).
+    </para>
+
+    <para>
+     Format specifiers are introduced by a <literal>%</literal> character and have
+     the form
+<synopsis>
+%[<parameter>position</parameter>][<parameter>flags</parameter>][<parameter>width</parameter>]<parameter>type</parameter>
+</synopsis>
+     where the component fields are:
+
+     <variablelist>
+      <varlistentry>
+       <term><parameter>position</parameter> (optional)</term>
+       <listitem>
+        <para>
+         A string of the form <literal><parameter>n</parameter>$</literal> where
+         <parameter>n</parameter> is the index of the argument to print.
+         Index 1 means the first argument after
+         <parameter>formatstr</parameter>.  If the <parameter>position</parameter> is
+         omitted, the default is to use the next argument in sequence.
+        </para>
+       </listitem>
+      </varlistentry>
+
+      <varlistentry>
+       <term><parameter>flags</parameter> (optional)</term>
+       <listitem>
+        <para>
+         Additional options controlling how the format specifier's output is
+         formatted.  Currently the only supported flag is a minus sign
+         (<literal>-</literal>) which will cause the format specifier's output to be
+         left-justified.  This has no effect unless the <parameter>width</parameter>
+         field is also specified.
+        </para>
+       </listitem>
+      </varlistentry>
+
+      <varlistentry>
+       <term><parameter>width</parameter> (optional)</term>
+       <listitem>
+        <para>
+         Specifies the <emphasis>minimum</emphasis> number of characters to use to
+         display the format specifier's output.  The output is padded on the
+         left or right (depending on the <literal>-</literal> flag) with spaces as
+         needed to fill the width.  A too-small width does not cause
+         truncation of the output, but is simply ignored.  The width may be
+         specified using any of the following: a positive integer; an
+         asterisk (<literal>*</literal>) to use the next function argument as the
+         width; or a string of the form <literal>*<parameter>n</parameter>$</literal> to
+         use the <parameter>n</parameter>th function argument as the width.
+        </para>
+
+        <para>
+         If the width comes from a function argument, that argument is
+         consumed before the argument that is used for the format specifier's
+         value.  If the width argument is negative, the result is left
+         aligned (as if the <literal>-</literal> flag had been specified) within a
+         field of length <function>abs</function>(<parameter>width</parameter>).
+        </para>
+       </listitem>
+      </varlistentry>
+
+      <varlistentry>
+       <term><parameter>type</parameter> (required)</term>
+       <listitem>
+        <para>
+         The type of format conversion to use to produce the format
+         specifier's output.  The following types are supported:
+         <itemizedlist>
+          <listitem>
+           <para>
+            <literal>s</literal> formats the argument value as a simple
+            string.  A null value is treated as an empty string.
+           </para>
+          </listitem>
+          <listitem>
+           <para>
+            <literal>I</literal> treats the argument value as an SQL
+            identifier, double-quoting it if necessary.
+            It is an error for the value to be null (equivalent to
+            <function>quote_ident</function>).
+           </para>
+          </listitem>
+          <listitem>
+           <para>
+            <literal>L</literal> quotes the argument value as an SQL literal.
+            A null value is displayed as the string <literal>NULL</literal>, without
+            quotes (equivalent to <function>quote_nullable</function>).
+           </para>
+          </listitem>
+         </itemizedlist>
+        </para>
+       </listitem>
+      </varlistentry>
+     </variablelist>
+    </para>
+
+    <para>
+     In addition to the format specifiers described above, the special sequence
+     <literal>%%</literal> may be used to output a literal <literal>%</literal> character.
+    </para>
+
+    <para>
+     Here are some examples of the basic format conversions:
+
+<screen>
+SELECT format('Hello %s', 'World');
+<lineannotation>Result: </lineannotation><computeroutput>Hello World</computeroutput>
+
+SELECT format('Testing %s, %s, %s, %%', 'one', 'two', 'three');
+<lineannotation>Result: </lineannotation><computeroutput>Testing one, two, three, %</computeroutput>
+
+SELECT format('INSERT INTO %I VALUES(%L)', 'Foo bar', E'O\'Reilly');
+<lineannotation>Result: </lineannotation><computeroutput>INSERT INTO "Foo bar" VALUES('O''Reilly')</computeroutput>
+
+SELECT format('INSERT INTO %I VALUES(%L)', 'locations', 'C:\Program Files');
+<lineannotation>Result: </lineannotation><computeroutput>INSERT INTO locations VALUES('C:\Program Files')</computeroutput>
+</screen>
+    </para>
+
+    <para>
+     Here are examples using <parameter>width</parameter> fields
+     and the <literal>-</literal> flag:
+
+<screen>
+SELECT format('|%10s|', 'foo');
+<lineannotation>Result: </lineannotation><computeroutput>|       foo|</computeroutput>
+
+SELECT format('|%-10s|', 'foo');
+<lineannotation>Result: </lineannotation><computeroutput>|foo       |</computeroutput>
+
+SELECT format('|%*s|', 10, 'foo');
+<lineannotation>Result: </lineannotation><computeroutput>|       foo|</computeroutput>
+
+SELECT format('|%*s|', -10, 'foo');
+<lineannotation>Result: </lineannotation><computeroutput>|foo       |</computeroutput>
+
+SELECT format('|%-*s|', 10, 'foo');
+<lineannotation>Result: </lineannotation><computeroutput>|foo       |</computeroutput>
+
+SELECT format('|%-*s|', -10, 'foo');
+<lineannotation>Result: </lineannotation><computeroutput>|foo       |</computeroutput>
+</screen>
+    </para>
+
+    <para>
+     These examples show use of <parameter>position</parameter> fields:
+
+<screen>
+SELECT format('Testing %3$s, %2$s, %1$s', 'one', 'two', 'three');
+<lineannotation>Result: </lineannotation><computeroutput>Testing three, two, one</computeroutput>
+
+SELECT format('|%*2$s|', 'foo', 10, 'bar');
+<lineannotation>Result: </lineannotation><computeroutput>|       bar|</computeroutput>
+
+SELECT format('|%1$*2$s|', 'foo', 10, 'bar');
+<lineannotation>Result: </lineannotation><computeroutput>|       foo|</computeroutput>
+</screen>
+    </para>
+
+    <para>
+     Unlike the standard C function <function>sprintf</function>,
+     <productname>PostgreSQL</productname>'s <function>format</function> function allows format
+     specifiers with and without <parameter>position</parameter> fields to be mixed
+     in the same format string.  A format specifier without a
+     <parameter>position</parameter> field always uses the next argument after the
+     last argument consumed.
+     In addition, the <function>format</function> function does not require all
+     function arguments to be used in the format string.
+     For example:
+
+<screen>
+SELECT format('Testing %3$s, %2$s, %s', 'one', 'two', 'three');
+<lineannotation>Result: </lineannotation><computeroutput>Testing three, two, three</computeroutput>
+</screen>
+    </para>
+
+    <para>
+     The <literal>%I</literal> and <literal>%L</literal> format specifiers are particularly
+     useful for safely constructing dynamic SQL statements.  See
+     <xref linkend="plpgsql-quote-literal-example"/>.
+    </para>
+   </sect2>
+
+  </sect1>
diff --git a/doc/src/sgml/func/func-subquery.sgml b/doc/src/sgml/func/func-subquery.sgml
new file mode 100644
index 0000000000000..a9f2b12e48c66
--- /dev/null
+++ b/doc/src/sgml/func/func-subquery.sgml
@@ -0,0 +1,349 @@
+ <sect1 id="functions-subquery">
+  <title>Subquery Expressions</title>
+
+  <indexterm>
+   <primary>EXISTS</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>IN</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>NOT IN</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>ANY</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>ALL</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>SOME</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>subquery</primary>
+  </indexterm>
+
+  <para>
+   This section describes the <acronym>SQL</acronym>-compliant subquery
+   expressions available in <productname>PostgreSQL</productname>.
+   All of the expression forms documented in this section return
+   Boolean (true/false) results.
+  </para>
+
+  <sect2 id="functions-subquery-exists">
+   <title><literal>EXISTS</literal></title>
+
+<synopsis>
+EXISTS (<replaceable>subquery</replaceable>)
+</synopsis>
+
+  <para>
+   The argument of <token>EXISTS</token> is an arbitrary <command>SELECT</command> statement,
+   or <firstterm>subquery</firstterm>.  The
+   subquery is evaluated to determine whether it returns any rows.
+   If it returns at least one row, the result of <token>EXISTS</token> is
+   <quote>true</quote>; if the subquery returns no rows, the result of <token>EXISTS</token>
+   is <quote>false</quote>.
+  </para>
+
+  <para>
+   The subquery can refer to variables from the surrounding query,
+   which will act as constants during any one evaluation of the subquery.
+  </para>
+
+  <para>
+   The subquery will generally only be executed long enough to determine
+   whether at least one row is returned, not all the way to completion.
+   It is unwise to write a subquery that has side effects (such as
+   calling sequence functions); whether the side effects occur
+   might be unpredictable.
+  </para>
+
+  <para>
+   Since the result depends only on whether any rows are returned,
+   and not on the contents of those rows, the output list of the
+   subquery is normally unimportant.  A common coding convention is
+   to write all <literal>EXISTS</literal> tests in the form
+   <literal>EXISTS(SELECT 1 WHERE ...)</literal>.  There are exceptions to
+   this rule however, such as subqueries that use <token>INTERSECT</token>.
+  </para>
+
+  <para>
+   This simple example is like an inner join on <literal>col2</literal>, but
+   it produces at most one output row for each <literal>tab1</literal> row,
+   even if there are several matching <literal>tab2</literal> rows:
+<screen>
+SELECT col1
+FROM tab1
+WHERE EXISTS (SELECT 1 FROM tab2 WHERE col2 = tab1.col2);
+</screen>
+  </para>
+  </sect2>
+
+  <sect2 id="functions-subquery-in">
+   <title><literal>IN</literal></title>
+
+<synopsis>
+<replaceable>expression</replaceable> IN (<replaceable>subquery</replaceable>)
+</synopsis>
+
+  <para>
+   The right-hand side is a parenthesized
+   subquery, which must return exactly one column.  The left-hand expression
+   is evaluated and compared to each row of the subquery result.
+   The result of <token>IN</token> is <quote>true</quote> if any equal subquery row is found.
+   The result is <quote>false</quote> if no equal row is found (including the
+   case where the subquery returns no rows).
+  </para>
+
+  <para>
+   Note that if the left-hand expression yields null, or if there are
+   no equal right-hand values and at least one right-hand row yields
+   null, the result of the <token>IN</token> construct will be null, not false.
+   This is in accordance with SQL's normal rules for Boolean combinations
+   of null values.
+  </para>
+
+  <para>
+   As with <token>EXISTS</token>, it's unwise to assume that the subquery will
+   be evaluated completely.
+  </para>
+
+<synopsis>
+<replaceable>row_constructor</replaceable> IN (<replaceable>subquery</replaceable>)
+</synopsis>
+
+  <para>
+   The left-hand side of this form of <token>IN</token> is a row constructor,
+   as described in <xref linkend="sql-syntax-row-constructors"/>.
+   The right-hand side is a parenthesized
+   subquery, which must return exactly as many columns as there are
+   expressions in the left-hand row.  The left-hand expressions are
+   evaluated and compared row-wise to each row of the subquery result.
+   The result of <token>IN</token> is <quote>true</quote> if any equal subquery row is found.
+   The result is <quote>false</quote> if no equal row is found (including the
+   case where the subquery returns no rows).
+  </para>
+
+  <para>
+   As usual, null values in the rows are combined per
+   the normal rules of SQL Boolean expressions.  Two rows are considered
+   equal if all their corresponding members are non-null and equal; the rows
+   are unequal if any corresponding members are non-null and unequal;
+   otherwise the result of that row comparison is unknown (null).
+   If all the per-row results are either unequal or null, with at least one
+   null, then the result of <token>IN</token> is null.
+  </para>
+  </sect2>
+
+  <sect2 id="functions-subquery-notin">
+   <title><literal>NOT IN</literal></title>
+
+<synopsis>
+<replaceable>expression</replaceable> NOT IN (<replaceable>subquery</replaceable>)
+</synopsis>
+
+  <para>
+   The right-hand side is a parenthesized
+   subquery, which must return exactly one column.  The left-hand expression
+   is evaluated and compared to each row of the subquery result.
+   The result of <token>NOT IN</token> is <quote>true</quote> if only unequal subquery rows
+   are found (including the case where the subquery returns no rows).
+   The result is <quote>false</quote> if any equal row is found.
+  </para>
+
+  <para>
+   Note that if the left-hand expression yields null, or if there are
+   no equal right-hand values and at least one right-hand row yields
+   null, the result of the <token>NOT IN</token> construct will be null, not true.
+   This is in accordance with SQL's normal rules for Boolean combinations
+   of null values.
+  </para>
+
+  <para>
+   As with <token>EXISTS</token>, it's unwise to assume that the subquery will
+   be evaluated completely.
+  </para>
+
+<synopsis>
+<replaceable>row_constructor</replaceable> NOT IN (<replaceable>subquery</replaceable>)
+</synopsis>
+
+  <para>
+   The left-hand side of this form of <token>NOT IN</token> is a row constructor,
+   as described in <xref linkend="sql-syntax-row-constructors"/>.
+   The right-hand side is a parenthesized
+   subquery, which must return exactly as many columns as there are
+   expressions in the left-hand row.  The left-hand expressions are
+   evaluated and compared row-wise to each row of the subquery result.
+   The result of <token>NOT IN</token> is <quote>true</quote> if only unequal subquery rows
+   are found (including the case where the subquery returns no rows).
+   The result is <quote>false</quote> if any equal row is found.
+  </para>
+
+  <para>
+   As usual, null values in the rows are combined per
+   the normal rules of SQL Boolean expressions.  Two rows are considered
+   equal if all their corresponding members are non-null and equal; the rows
+   are unequal if any corresponding members are non-null and unequal;
+   otherwise the result of that row comparison is unknown (null).
+   If all the per-row results are either unequal or null, with at least one
+   null, then the result of <token>NOT IN</token> is null.
+  </para>
+  </sect2>
+
+  <sect2 id="functions-subquery-any-some">
+   <title><literal>ANY</literal>/<literal>SOME</literal></title>
+
+<synopsis>
+<replaceable>expression</replaceable> <replaceable>operator</replaceable> ANY (<replaceable>subquery</replaceable>)
+<replaceable>expression</replaceable> <replaceable>operator</replaceable> SOME (<replaceable>subquery</replaceable>)
+</synopsis>
+
+  <para>
+   The right-hand side is a parenthesized
+   subquery, which must return exactly one column.  The left-hand expression
+   is evaluated and compared to each row of the subquery result using the
+   given <replaceable>operator</replaceable>, which must yield a Boolean
+   result.
+   The result of <token>ANY</token> is <quote>true</quote> if any true result is obtained.
+   The result is <quote>false</quote> if no true result is found (including the
+   case where the subquery returns no rows).
+  </para>
+
+  <para>
+   <token>SOME</token> is a synonym for <token>ANY</token>.
+   <token>IN</token> is equivalent to <literal>= ANY</literal>.
+  </para>
+
+  <para>
+   Note that if there are no successes and at least one right-hand row yields
+   null for the operator's result, the result of the <token>ANY</token> construct
+   will be null, not false.
+   This is in accordance with SQL's normal rules for Boolean combinations
+   of null values.
+  </para>
+
+  <para>
+   As with <token>EXISTS</token>, it's unwise to assume that the subquery will
+   be evaluated completely.
+  </para>
+
+<synopsis>
+<replaceable>row_constructor</replaceable> <replaceable>operator</replaceable> ANY (<replaceable>subquery</replaceable>)
+<replaceable>row_constructor</replaceable> <replaceable>operator</replaceable> SOME (<replaceable>subquery</replaceable>)
+</synopsis>
+
+  <para>
+   The left-hand side of this form of <token>ANY</token> is a row constructor,
+   as described in <xref linkend="sql-syntax-row-constructors"/>.
+   The right-hand side is a parenthesized
+   subquery, which must return exactly as many columns as there are
+   expressions in the left-hand row.  The left-hand expressions are
+   evaluated and compared row-wise to each row of the subquery result,
+   using the given <replaceable>operator</replaceable>.
+   The result of <token>ANY</token> is <quote>true</quote> if the comparison
+   returns true for any subquery row.
+   The result is <quote>false</quote> if the comparison returns false for every
+   subquery row (including the case where the subquery returns no
+   rows).
+   The result is NULL if no comparison with a subquery row returns true,
+   and at least one comparison returns NULL.
+  </para>
+
+  <para>
+   See <xref linkend="row-wise-comparison"/> for details about the meaning
+   of a row constructor comparison.
+  </para>
+  </sect2>
+
+  <sect2 id="functions-subquery-all">
+   <title><literal>ALL</literal></title>
+
+<synopsis>
+<replaceable>expression</replaceable> <replaceable>operator</replaceable> ALL (<replaceable>subquery</replaceable>)
+</synopsis>
+
+  <para>
+   The right-hand side is a parenthesized
+   subquery, which must return exactly one column.  The left-hand expression
+   is evaluated and compared to each row of the subquery result using the
+   given <replaceable>operator</replaceable>, which must yield a Boolean
+   result.
+   The result of <token>ALL</token> is <quote>true</quote> if all rows yield true
+   (including the case where the subquery returns no rows).
+   The result is <quote>false</quote> if any false result is found.
+   The result is NULL if no comparison with a subquery row returns false,
+   and at least one comparison returns NULL.
+  </para>
+
+  <para>
+   <token>NOT IN</token> is equivalent to <literal>&lt;&gt; ALL</literal>.
+  </para>
+
+  <para>
+   As with <token>EXISTS</token>, it's unwise to assume that the subquery will
+   be evaluated completely.
+  </para>
+
+<synopsis>
+<replaceable>row_constructor</replaceable> <replaceable>operator</replaceable> ALL (<replaceable>subquery</replaceable>)
+</synopsis>
+
+  <para>
+   The left-hand side of this form of <token>ALL</token> is a row constructor,
+   as described in <xref linkend="sql-syntax-row-constructors"/>.
+   The right-hand side is a parenthesized
+   subquery, which must return exactly as many columns as there are
+   expressions in the left-hand row.  The left-hand expressions are
+   evaluated and compared row-wise to each row of the subquery result,
+   using the given <replaceable>operator</replaceable>.
+   The result of <token>ALL</token> is <quote>true</quote> if the comparison
+   returns true for all subquery rows (including the
+   case where the subquery returns no rows).
+   The result is <quote>false</quote> if the comparison returns false for any
+   subquery row.
+   The result is NULL if no comparison with a subquery row returns false,
+   and at least one comparison returns NULL.
+  </para>
+
+  <para>
+   See <xref linkend="row-wise-comparison"/> for details about the meaning
+   of a row constructor comparison.
+  </para>
+  </sect2>
+
+  <sect2 id="functions-subquery-single-row-comp">
+   <title>Single-Row Comparison</title>
+
+   <indexterm zone="functions-subquery">
+    <primary>comparison</primary>
+    <secondary>subquery result row</secondary>
+   </indexterm>
+
+<synopsis>
+<replaceable>row_constructor</replaceable> <replaceable>operator</replaceable> (<replaceable>subquery</replaceable>)
+</synopsis>
+
+  <para>
+   The left-hand side is a row constructor,
+   as described in <xref linkend="sql-syntax-row-constructors"/>.
+   The right-hand side is a parenthesized subquery, which must return exactly
+   as many columns as there are expressions in the left-hand row. Furthermore,
+   the subquery cannot return more than one row.  (If it returns zero rows,
+   the result is taken to be null.)  The left-hand side is evaluated and
+   compared row-wise to the single subquery result row.
+  </para>
+
+  <para>
+   See <xref linkend="row-wise-comparison"/> for details about the meaning
+   of a row constructor comparison.
+  </para>
+  </sect2>
+ </sect1>
diff --git a/doc/src/sgml/func/func-textsearch.sgml b/doc/src/sgml/func/func-textsearch.sgml
new file mode 100644
index 0000000000000..a06a58f14983a
--- /dev/null
+++ b/doc/src/sgml/func/func-textsearch.sgml
@@ -0,0 +1,1046 @@
+ <sect1 id="functions-textsearch">
+  <title>Text Search Functions and Operators</title>
+
+   <indexterm zone="datatype-textsearch">
+    <primary>full text search</primary>
+    <secondary>functions and operators</secondary>
+   </indexterm>
+
+   <indexterm zone="datatype-textsearch">
+    <primary>text search</primary>
+    <secondary>functions and operators</secondary>
+   </indexterm>
+
+  <para>
+   <xref linkend="textsearch-operators-table"/>,
+   <xref linkend="textsearch-functions-table"/> and
+   <xref linkend="textsearch-functions-debug-table"/>
+   summarize the functions and operators that are provided
+   for full text searching.  See <xref linkend="textsearch"/> for a detailed
+   explanation of <productname>PostgreSQL</productname>'s text search
+   facility.
+  </para>
+
+   <table id="textsearch-operators-table">
+    <title>Text Search Operators</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Operator
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>tsvector</type> <literal>@@</literal> <type>tsquery</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para role="func_signature">
+        <type>tsquery</type> <literal>@@</literal> <type>tsvector</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does <type>tsvector</type> match <type>tsquery</type>?
+        (The arguments can be given in either order.)
+       </para>
+       <para>
+        <literal>to_tsvector('fat cats ate rats') @@ to_tsquery('cat &amp; rat')</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>text</type> <literal>@@</literal> <type>tsquery</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does text string, after implicit invocation
+        of <function>to_tsvector()</function>, match <type>tsquery</type>?
+       </para>
+       <para>
+        <literal>'fat cats ate rats' @@ to_tsquery('cat &amp; rat')</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>tsvector</type> <literal>||</literal> <type>tsvector</type>
+        <returnvalue>tsvector</returnvalue>
+       </para>
+       <para>
+        Concatenates two <type>tsvector</type>s.  If both inputs contain
+        lexeme positions, the second input's positions are adjusted
+        accordingly.
+       </para>
+       <para>
+        <literal>'a:1 b:2'::tsvector || 'c:1 d:2 b:3'::tsvector</literal>
+        <returnvalue>'a':1 'b':2,5 'c':3 'd':4</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>tsquery</type> <literal>&amp;&amp;</literal> <type>tsquery</type>
+        <returnvalue>tsquery</returnvalue>
+       </para>
+       <para>
+        ANDs two <type>tsquery</type>s together, producing a query that
+        matches documents that match both input queries.
+       </para>
+       <para>
+        <literal>'fat | rat'::tsquery &amp;&amp; 'cat'::tsquery</literal>
+        <returnvalue>( 'fat' | 'rat' ) &amp; 'cat'</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>tsquery</type> <literal>||</literal> <type>tsquery</type>
+        <returnvalue>tsquery</returnvalue>
+       </para>
+       <para>
+        ORs two <type>tsquery</type>s together, producing a query that
+        matches documents that match either input query.
+       </para>
+       <para>
+        <literal>'fat | rat'::tsquery || 'cat'::tsquery</literal>
+        <returnvalue>'fat' | 'rat' | 'cat'</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <literal>!!</literal> <type>tsquery</type>
+        <returnvalue>tsquery</returnvalue>
+       </para>
+       <para>
+        Negates a <type>tsquery</type>, producing a query that matches
+        documents that do not match the input query.
+       </para>
+       <para>
+        <literal>!! 'cat'::tsquery</literal>
+        <returnvalue>!'cat'</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>tsquery</type> <literal>&lt;-&gt;</literal> <type>tsquery</type>
+        <returnvalue>tsquery</returnvalue>
+       </para>
+       <para>
+        Constructs a phrase query, which matches if the two input queries
+        match at successive lexemes.
+       </para>
+       <para>
+        <literal>to_tsquery('fat') &lt;-&gt; to_tsquery('rat')</literal>
+        <returnvalue>'fat' &lt;-&gt; 'rat'</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>tsquery</type> <literal>@&gt;</literal> <type>tsquery</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Does first <type>tsquery</type> contain the second?  (This considers
+        only whether all the lexemes appearing in one query appear in the
+        other, ignoring the combining operators.)
+       </para>
+       <para>
+        <literal>'cat'::tsquery @&gt; 'cat &amp; rat'::tsquery</literal>
+        <returnvalue>f</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <type>tsquery</type> <literal>&lt;@</literal> <type>tsquery</type>
+        <returnvalue>boolean</returnvalue>
+       </para>
+       <para>
+        Is first <type>tsquery</type> contained in the second?  (This
+        considers only whether all the lexemes appearing in one query appear
+        in the other, ignoring the combining operators.)
+       </para>
+       <para>
+        <literal>'cat'::tsquery &lt;@ 'cat &amp; rat'::tsquery</literal>
+        <returnvalue>t</returnvalue>
+       </para>
+       <para>
+        <literal>'cat'::tsquery &lt;@ '!cat &amp; rat'::tsquery</literal>
+        <returnvalue>t</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+    <para>
+     In addition to these specialized operators, the usual comparison
+     operators shown in <xref linkend="functions-comparison-op-table"/> are
+     available for types <type>tsvector</type> and <type>tsquery</type>.
+     These are not very
+     useful for text searching but allow, for example, unique indexes to be
+     built on columns of these types.
+    </para>
+
+   <table id="textsearch-functions-table">
+    <title>Text Search Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>array_to_tsvector</primary>
+        </indexterm>
+        <function>array_to_tsvector</function> ( <type>text[]</type> )
+        <returnvalue>tsvector</returnvalue>
+       </para>
+       <para>
+        Converts an array of text strings to a <type>tsvector</type>.
+        The given strings are used as lexemes as-is, without further
+        processing.  Array elements must not be empty strings
+        or <literal>NULL</literal>.
+       </para>
+       <para>
+        <literal>array_to_tsvector('{fat,cat,rat}'::text[])</literal>
+        <returnvalue>'cat' 'fat' 'rat'</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>get_current_ts_config</primary>
+        </indexterm>
+        <function>get_current_ts_config</function> ( )
+        <returnvalue>regconfig</returnvalue>
+       </para>
+       <para>
+        Returns the OID of the current default text search configuration
+        (as set by <xref linkend="guc-default-text-search-config"/>).
+       </para>
+       <para>
+        <literal>get_current_ts_config()</literal>
+        <returnvalue>english</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>length</primary>
+        </indexterm>
+        <function>length</function> ( <type>tsvector</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the number of lexemes in the <type>tsvector</type>.
+       </para>
+       <para>
+        <literal>length('fat:2,4 cat:3 rat:5A'::tsvector)</literal>
+        <returnvalue>3</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>numnode</primary>
+        </indexterm>
+        <function>numnode</function> ( <type>tsquery</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns the number of lexemes plus operators in
+        the <type>tsquery</type>.
+       </para>
+       <para>
+        <literal>numnode('(fat &amp; rat) | cat'::tsquery)</literal>
+        <returnvalue>5</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>plainto_tsquery</primary>
+        </indexterm>
+        <function>plainto_tsquery</function> (
+        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
+        <parameter>query</parameter> <type>text</type> )
+        <returnvalue>tsquery</returnvalue>
+       </para>
+       <para>
+        Converts text to a <type>tsquery</type>, normalizing words according to
+        the specified or default configuration.  Any punctuation in the string
+        is ignored (it does not determine query operators).  The resulting
+        query matches documents containing all non-stopwords in the text.
+       </para>
+       <para>
+        <literal>plainto_tsquery('english', 'The Fat Rats')</literal>
+        <returnvalue>'fat' &amp; 'rat'</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>phraseto_tsquery</primary>
+        </indexterm>
+        <function>phraseto_tsquery</function> (
+        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
+        <parameter>query</parameter> <type>text</type> )
+        <returnvalue>tsquery</returnvalue>
+       </para>
+       <para>
+        Converts text to a <type>tsquery</type>, normalizing words according to
+        the specified or default configuration.  Any punctuation in the string
+        is ignored (it does not determine query operators).  The resulting
+        query matches phrases containing all non-stopwords in the text.
+       </para>
+       <para>
+        <literal>phraseto_tsquery('english', 'The Fat Rats')</literal>
+        <returnvalue>'fat' &lt;-&gt; 'rat'</returnvalue>
+       </para>
+       <para>
+        <literal>phraseto_tsquery('english', 'The Cat and Rats')</literal>
+        <returnvalue>'cat' &lt;2&gt; 'rat'</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>websearch_to_tsquery</primary>
+        </indexterm>
+        <function>websearch_to_tsquery</function> (
+        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
+        <parameter>query</parameter> <type>text</type> )
+        <returnvalue>tsquery</returnvalue>
+       </para>
+       <para>
+        Converts text to a <type>tsquery</type>, normalizing words according
+        to the specified or default configuration.  Quoted word sequences are
+        converted to phrase tests.  The word <quote>or</quote> is understood
+        as producing an OR operator, and a dash produces a NOT operator;
+        other punctuation is ignored.
+        This approximates the behavior of some common web search tools.
+       </para>
+       <para>
+        <literal>websearch_to_tsquery('english', '"fat rat" or cat dog')</literal>
+        <returnvalue>'fat' &lt;-&gt; 'rat' | 'cat' &amp; 'dog'</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>querytree</primary>
+        </indexterm>
+        <function>querytree</function> ( <type>tsquery</type> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Produces a representation of the indexable portion of
+        a <type>tsquery</type>.  A result that is empty or
+        just <literal>T</literal> indicates a non-indexable query.
+       </para>
+       <para>
+        <literal>querytree('foo &amp; ! bar'::tsquery)</literal>
+        <returnvalue>'foo'</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>setweight</primary>
+        </indexterm>
+        <function>setweight</function> ( <parameter>vector</parameter> <type>tsvector</type>, <parameter>weight</parameter> <type>"char"</type> )
+        <returnvalue>tsvector</returnvalue>
+       </para>
+       <para>
+        Assigns the specified <parameter>weight</parameter> to each element
+        of the <parameter>vector</parameter>.
+       </para>
+       <para>
+        <literal>setweight('fat:2,4 cat:3 rat:5B'::tsvector, 'A')</literal>
+        <returnvalue>'cat':3A 'fat':2A,4A 'rat':5A</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>setweight</primary>
+         <secondary>setweight for specific lexeme(s)</secondary>
+        </indexterm>
+        <function>setweight</function> ( <parameter>vector</parameter> <type>tsvector</type>, <parameter>weight</parameter> <type>"char"</type>, <parameter>lexemes</parameter> <type>text[]</type> )
+        <returnvalue>tsvector</returnvalue>
+       </para>
+       <para>
+        Assigns the specified <parameter>weight</parameter> to elements
+        of the <parameter>vector</parameter> that are listed
+        in <parameter>lexemes</parameter>.
+        The strings in <parameter>lexemes</parameter> are taken as lexemes
+        as-is, without further processing.  Strings that do not match any
+        lexeme in <parameter>vector</parameter> are ignored.
+       </para>
+       <para>
+        <literal>setweight('fat:2,4 cat:3 rat:5,6B'::tsvector, 'A', '{cat,rat}')</literal>
+        <returnvalue>'cat':3A 'fat':2,4 'rat':5A,6A</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>strip</primary>
+        </indexterm>
+        <function>strip</function> ( <type>tsvector</type> )
+        <returnvalue>tsvector</returnvalue>
+       </para>
+       <para>
+        Removes positions and weights from the <type>tsvector</type>.
+       </para>
+       <para>
+        <literal>strip('fat:2,4 cat:3 rat:5A'::tsvector)</literal>
+        <returnvalue>'cat' 'fat' 'rat'</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_tsquery</primary>
+        </indexterm>
+        <function>to_tsquery</function> (
+        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
+        <parameter>query</parameter> <type>text</type> )
+        <returnvalue>tsquery</returnvalue>
+       </para>
+       <para>
+        Converts text to a <type>tsquery</type>, normalizing words according to
+        the specified or default configuration.  The words must be combined
+        by valid <type>tsquery</type> operators.
+       </para>
+       <para>
+        <literal>to_tsquery('english', 'The &amp; Fat &amp; Rats')</literal>
+        <returnvalue>'fat' &amp; 'rat'</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>to_tsvector</primary>
+        </indexterm>
+        <function>to_tsvector</function> (
+        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
+         <parameter>document</parameter> <type>text</type> )
+        <returnvalue>tsvector</returnvalue>
+       </para>
+       <para>
+        Converts text to a <type>tsvector</type>, normalizing words according
+        to the specified or default configuration.  Position information is
+        included in the result.
+       </para>
+       <para>
+        <literal>to_tsvector('english', 'The Fat Rats')</literal>
+        <returnvalue>'fat':2 'rat':3</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>to_tsvector</function> (
+        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
+        <parameter>document</parameter> <type>json</type> )
+        <returnvalue>tsvector</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>to_tsvector</function> (
+        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
+        <parameter>document</parameter> <type>jsonb</type> )
+        <returnvalue>tsvector</returnvalue>
+       </para>
+       <para>
+        Converts each string value in the JSON document to
+        a <type>tsvector</type>, normalizing words according to the specified
+        or default configuration.  The results are then concatenated in
+        document order to produce the output.  Position information is
+        generated as though one stopword exists between each pair of string
+        values.  (Beware that <quote>document order</quote> of the fields of a
+        JSON object is implementation-dependent when the input
+        is <type>jsonb</type>; observe the difference in the examples.)
+       </para>
+       <para>
+        <literal>to_tsvector('english', '{"aa": "The Fat Rats", "b": "dog"}'::json)</literal>
+        <returnvalue>'dog':5 'fat':2 'rat':3</returnvalue>
+       </para>
+       <para>
+        <literal>to_tsvector('english', '{"aa": "The Fat Rats", "b": "dog"}'::jsonb)</literal>
+        <returnvalue>'dog':1 'fat':4 'rat':5</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>json_to_tsvector</primary>
+        </indexterm>
+        <function>json_to_tsvector</function> (
+        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
+        <parameter>document</parameter> <type>json</type>,
+        <parameter>filter</parameter> <type>jsonb</type> )
+        <returnvalue>tsvector</returnvalue>
+       </para>
+       <para role="func_signature">
+        <indexterm>
+         <primary>jsonb_to_tsvector</primary>
+        </indexterm>
+        <function>jsonb_to_tsvector</function> (
+        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
+        <parameter>document</parameter> <type>jsonb</type>,
+        <parameter>filter</parameter> <type>jsonb</type> )
+        <returnvalue>tsvector</returnvalue>
+       </para>
+       <para>
+        Selects each item in the JSON document that is requested by
+        the <parameter>filter</parameter> and converts each one to
+        a <type>tsvector</type>, normalizing words according to the specified
+        or default configuration.  The results are then concatenated in
+        document order to produce the output.  Position information is
+        generated as though one stopword exists between each pair of selected
+        items.  (Beware that <quote>document order</quote> of the fields of a
+        JSON object is implementation-dependent when the input
+        is <type>jsonb</type>.)
+        The <parameter>filter</parameter> must be a <type>jsonb</type>
+        array containing zero or more of these keywords:
+        <literal>"string"</literal> (to include all string values),
+        <literal>"numeric"</literal> (to include all numeric values),
+        <literal>"boolean"</literal> (to include all boolean values),
+        <literal>"key"</literal> (to include all keys), or
+        <literal>"all"</literal> (to include all the above).
+        As a special case, the <parameter>filter</parameter> can also be a
+        simple JSON value that is one of these keywords.
+       </para>
+       <para>
+        <literal>json_to_tsvector('english', '{"a": "The Fat Rats", "b": 123}'::json, '["string", "numeric"]')</literal>
+        <returnvalue>'123':5 'fat':2 'rat':3</returnvalue>
+       </para>
+       <para>
+        <literal>json_to_tsvector('english', '{"cat": "The Fat Rats", "dog": 123}'::json, '"all"')</literal>
+        <returnvalue>'123':9 'cat':1 'dog':7 'fat':4 'rat':5</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>ts_delete</primary>
+        </indexterm>
+        <function>ts_delete</function> ( <parameter>vector</parameter> <type>tsvector</type>, <parameter>lexeme</parameter> <type>text</type> )
+        <returnvalue>tsvector</returnvalue>
+       </para>
+       <para>
+        Removes any occurrence of the given <parameter>lexeme</parameter>
+        from the <parameter>vector</parameter>.
+        The <parameter>lexeme</parameter> string is treated as a lexeme as-is,
+        without further processing.
+       </para>
+       <para>
+        <literal>ts_delete('fat:2,4 cat:3 rat:5A'::tsvector, 'fat')</literal>
+        <returnvalue>'cat':3 'rat':5A</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>ts_delete</function> ( <parameter>vector</parameter> <type>tsvector</type>, <parameter>lexemes</parameter> <type>text[]</type> )
+        <returnvalue>tsvector</returnvalue>
+       </para>
+       <para>
+        Removes any occurrences of the lexemes
+        in <parameter>lexemes</parameter>
+        from the <parameter>vector</parameter>.
+        The strings in <parameter>lexemes</parameter> are taken as lexemes
+        as-is, without further processing.  Strings that do not match any
+        lexeme in <parameter>vector</parameter> are ignored.
+       </para>
+       <para>
+        <literal>ts_delete('fat:2,4 cat:3 rat:5A'::tsvector, ARRAY['fat','rat'])</literal>
+        <returnvalue>'cat':3</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>ts_filter</primary>
+        </indexterm>
+        <function>ts_filter</function> ( <parameter>vector</parameter> <type>tsvector</type>, <parameter>weights</parameter> <type>"char"[]</type> )
+        <returnvalue>tsvector</returnvalue>
+       </para>
+       <para>
+        Selects only elements with the given <parameter>weights</parameter>
+        from the <parameter>vector</parameter>.
+       </para>
+       <para>
+        <literal>ts_filter('fat:2,4 cat:3b,7c rat:5A'::tsvector, '{a,b}')</literal>
+        <returnvalue>'cat':3B 'rat':5A</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>ts_headline</primary>
+        </indexterm>
+        <function>ts_headline</function> (
+        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
+        <parameter>document</parameter> <type>text</type>,
+        <parameter>query</parameter> <type>tsquery</type>
+        <optional>, <parameter>options</parameter> <type>text</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Displays, in an abbreviated form, the match(es) for
+        the <parameter>query</parameter> in
+        the <parameter>document</parameter>, which must be raw text not
+        a <type>tsvector</type>.  Words in the document are normalized
+        according to the specified or default configuration before matching to
+        the query.  Use of this function is discussed in
+        <xref linkend="textsearch-headline"/>, which also describes the
+        available <parameter>options</parameter>.
+       </para>
+       <para>
+        <literal>ts_headline('The fat cat ate the rat.', 'cat')</literal>
+        <returnvalue>The fat &lt;b&gt;cat&lt;/b&gt; ate the rat.</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>ts_headline</function> (
+        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
+        <parameter>document</parameter> <type>json</type>,
+        <parameter>query</parameter> <type>tsquery</type>
+        <optional>, <parameter>options</parameter> <type>text</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para role="func_signature">
+        <function>ts_headline</function> (
+        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
+        <parameter>document</parameter> <type>jsonb</type>,
+        <parameter>query</parameter> <type>tsquery</type>
+        <optional>, <parameter>options</parameter> <type>text</type> </optional> )
+        <returnvalue>text</returnvalue>
+       </para>
+       <para>
+        Displays, in an abbreviated form, match(es) for
+        the <parameter>query</parameter> that occur in string values
+        within the JSON <parameter>document</parameter>.
+        See <xref linkend="textsearch-headline"/> for more details.
+       </para>
+       <para>
+        <literal>ts_headline('{"cat":"raining cats and dogs"}'::jsonb, 'cat')</literal>
+        <returnvalue>{"cat": "raining &lt;b&gt;cats&lt;/b&gt; and dogs"}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>ts_rank</primary>
+        </indexterm>
+        <function>ts_rank</function> (
+        <optional> <parameter>weights</parameter> <type>real[]</type>, </optional>
+        <parameter>vector</parameter> <type>tsvector</type>,
+        <parameter>query</parameter> <type>tsquery</type>
+        <optional>, <parameter>normalization</parameter> <type>integer</type> </optional> )
+        <returnvalue>real</returnvalue>
+       </para>
+       <para>
+        Computes a score showing how well
+        the <parameter>vector</parameter> matches
+        the <parameter>query</parameter>.  See
+        <xref linkend="textsearch-ranking"/> for details.
+       </para>
+       <para>
+        <literal>ts_rank(to_tsvector('raining cats and dogs'), 'cat')</literal>
+        <returnvalue>0.06079271</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>ts_rank_cd</primary>
+        </indexterm>
+        <function>ts_rank_cd</function> (
+        <optional> <parameter>weights</parameter> <type>real[]</type>, </optional>
+        <parameter>vector</parameter> <type>tsvector</type>,
+        <parameter>query</parameter> <type>tsquery</type>
+        <optional>, <parameter>normalization</parameter> <type>integer</type> </optional> )
+        <returnvalue>real</returnvalue>
+       </para>
+       <para>
+        Computes a score showing how well
+        the <parameter>vector</parameter> matches
+        the <parameter>query</parameter>, using a cover density
+        algorithm.  See <xref linkend="textsearch-ranking"/> for details.
+       </para>
+       <para>
+        <literal>ts_rank_cd(to_tsvector('raining cats and dogs'), 'cat')</literal>
+        <returnvalue>0.1</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>ts_rewrite</primary>
+        </indexterm>
+        <function>ts_rewrite</function> ( <parameter>query</parameter> <type>tsquery</type>,
+        <parameter>target</parameter> <type>tsquery</type>,
+        <parameter>substitute</parameter> <type>tsquery</type> )
+        <returnvalue>tsquery</returnvalue>
+       </para>
+       <para>
+        Replaces occurrences of <parameter>target</parameter>
+        with <parameter>substitute</parameter>
+        within the <parameter>query</parameter>.
+        See <xref linkend="textsearch-query-rewriting"/> for details.
+       </para>
+       <para>
+        <literal>ts_rewrite('a &amp; b'::tsquery, 'a'::tsquery, 'foo|bar'::tsquery)</literal>
+        <returnvalue>'b' &amp; ( 'foo' | 'bar' )</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>ts_rewrite</function> ( <parameter>query</parameter> <type>tsquery</type>,
+        <parameter>select</parameter> <type>text</type> )
+        <returnvalue>tsquery</returnvalue>
+       </para>
+       <para>
+        Replaces portions of the <parameter>query</parameter> according to
+        target(s) and substitute(s) obtained by executing
+        a <command>SELECT</command> command.
+        See <xref linkend="textsearch-query-rewriting"/> for details.
+       </para>
+       <para>
+        <literal>SELECT ts_rewrite('a &amp; b'::tsquery, 'SELECT t,s FROM aliases')</literal>
+        <returnvalue>'b' &amp; ( 'foo' | 'bar' )</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>tsquery_phrase</primary>
+        </indexterm>
+        <function>tsquery_phrase</function> ( <parameter>query1</parameter> <type>tsquery</type>, <parameter>query2</parameter> <type>tsquery</type> )
+        <returnvalue>tsquery</returnvalue>
+       </para>
+       <para>
+        Constructs a phrase query that searches
+        for matches of <parameter>query1</parameter>
+        and <parameter>query2</parameter> at successive lexemes (same
+        as <literal>&lt;-&gt;</literal> operator).
+       </para>
+       <para>
+        <literal>tsquery_phrase(to_tsquery('fat'), to_tsquery('cat'))</literal>
+        <returnvalue>'fat' &lt;-&gt; 'cat'</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>tsquery_phrase</function> ( <parameter>query1</parameter> <type>tsquery</type>, <parameter>query2</parameter> <type>tsquery</type>, <parameter>distance</parameter> <type>integer</type> )
+        <returnvalue>tsquery</returnvalue>
+       </para>
+       <para>
+        Constructs a phrase query that searches
+        for matches of <parameter>query1</parameter> and
+        <parameter>query2</parameter> that occur exactly
+        <parameter>distance</parameter> lexemes apart.
+       </para>
+       <para>
+        <literal>tsquery_phrase(to_tsquery('fat'), to_tsquery('cat'), 10)</literal>
+        <returnvalue>'fat' &lt;10&gt; 'cat'</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>tsvector_to_array</primary>
+        </indexterm>
+        <function>tsvector_to_array</function> ( <type>tsvector</type> )
+        <returnvalue>text[]</returnvalue>
+       </para>
+       <para>
+        Converts a <type>tsvector</type> to an array of lexemes.
+       </para>
+       <para>
+        <literal>tsvector_to_array('fat:2,4 cat:3 rat:5A'::tsvector)</literal>
+        <returnvalue>{cat,fat,rat}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>unnest</primary>
+         <secondary>for tsvector</secondary>
+        </indexterm>
+        <function>unnest</function> ( <type>tsvector</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>lexeme</parameter> <type>text</type>,
+        <parameter>positions</parameter> <type>smallint[]</type>,
+        <parameter>weights</parameter> <type>text</type> )
+       </para>
+       <para>
+        Expands a <type>tsvector</type> into a set of rows, one per lexeme.
+       </para>
+       <para>
+        <literal>select * from unnest('cat:3 fat:2,4 rat:5A'::tsvector)</literal>
+        <returnvalue></returnvalue>
+<programlisting>
+ lexeme | positions | weights
+--------+-----------+---------
+ cat    | {3}       | {D}
+ fat    | {2,4}     | {D,D}
+ rat    | {5}       | {A}
+</programlisting>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <note>
+   <para>
+    All the text search functions that accept an optional <type>regconfig</type>
+    argument will use the configuration specified by
+    <xref linkend="guc-default-text-search-config"/>
+    when that argument is omitted.
+   </para>
+  </note>
+
+  <para>
+   The functions in
+   <xref linkend="textsearch-functions-debug-table"/>
+   are listed separately because they are not usually used in everyday text
+   searching operations.  They are primarily helpful for development and
+   debugging of new text search configurations.
+  </para>
+
+   <table id="textsearch-functions-debug-table">
+    <title>Text Search Debugging Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>ts_debug</primary>
+        </indexterm>
+        <function>ts_debug</function> (
+        <optional> <parameter>config</parameter> <type>regconfig</type>, </optional>
+        <parameter>document</parameter> <type>text</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>alias</parameter> <type>text</type>,
+        <parameter>description</parameter> <type>text</type>,
+        <parameter>token</parameter> <type>text</type>,
+        <parameter>dictionaries</parameter> <type>regdictionary[]</type>,
+        <parameter>dictionary</parameter> <type>regdictionary</type>,
+        <parameter>lexemes</parameter> <type>text[]</type> )
+       </para>
+       <para>
+        Extracts and normalizes tokens from
+        the <parameter>document</parameter> according to the specified or
+        default text search configuration, and returns information about how
+        each token was processed.
+        See <xref linkend="textsearch-configuration-testing"/> for details.
+       </para>
+       <para>
+        <literal>ts_debug('english', 'The Brightest supernovaes')</literal>
+        <returnvalue>(asciiword,"Word, all ASCII",The,{english_stem},english_stem,{}) ...</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>ts_lexize</primary>
+        </indexterm>
+        <function>ts_lexize</function> ( <parameter>dict</parameter> <type>regdictionary</type>, <parameter>token</parameter> <type>text</type> )
+        <returnvalue>text[]</returnvalue>
+       </para>
+       <para>
+        Returns an array of replacement lexemes if the input token is known to
+        the dictionary, or an empty array if the token is known to the
+        dictionary but it is a stop word, or NULL if it is not a known word.
+        See <xref linkend="textsearch-dictionary-testing"/> for details.
+       </para>
+       <para>
+        <literal>ts_lexize('english_stem', 'stars')</literal>
+        <returnvalue>{star}</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>ts_parse</primary>
+        </indexterm>
+        <function>ts_parse</function> ( <parameter>parser_name</parameter> <type>text</type>,
+        <parameter>document</parameter> <type>text</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>tokid</parameter> <type>integer</type>,
+        <parameter>token</parameter> <type>text</type> )
+       </para>
+       <para>
+        Extracts tokens from the <parameter>document</parameter> using the
+        named parser.
+        See <xref linkend="textsearch-parser-testing"/> for details.
+       </para>
+       <para>
+        <literal>ts_parse('default', 'foo - bar')</literal>
+        <returnvalue>(1,foo) ...</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>ts_parse</function> ( <parameter>parser_oid</parameter> <type>oid</type>,
+        <parameter>document</parameter> <type>text</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>tokid</parameter> <type>integer</type>,
+        <parameter>token</parameter> <type>text</type> )
+       </para>
+       <para>
+        Extracts tokens from the <parameter>document</parameter> using a
+        parser specified by OID.
+        See <xref linkend="textsearch-parser-testing"/> for details.
+       </para>
+       <para>
+        <literal>ts_parse(3722, 'foo - bar')</literal>
+        <returnvalue>(1,foo) ...</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>ts_token_type</primary>
+        </indexterm>
+        <function>ts_token_type</function> ( <parameter>parser_name</parameter> <type>text</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>tokid</parameter> <type>integer</type>,
+        <parameter>alias</parameter> <type>text</type>,
+        <parameter>description</parameter> <type>text</type> )
+       </para>
+       <para>
+        Returns a table that describes each type of token the named parser can
+        recognize.
+        See <xref linkend="textsearch-parser-testing"/> for details.
+       </para>
+       <para>
+        <literal>ts_token_type('default')</literal>
+        <returnvalue>(1,asciiword,"Word, all ASCII") ...</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <function>ts_token_type</function> ( <parameter>parser_oid</parameter> <type>oid</type> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>tokid</parameter> <type>integer</type>,
+        <parameter>alias</parameter> <type>text</type>,
+        <parameter>description</parameter> <type>text</type> )
+       </para>
+       <para>
+        Returns a table that describes each type of token a parser specified
+        by OID can recognize.
+        See <xref linkend="textsearch-parser-testing"/> for details.
+       </para>
+       <para>
+        <literal>ts_token_type(3722)</literal>
+        <returnvalue>(1,asciiword,"Word, all ASCII") ...</returnvalue>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>ts_stat</primary>
+        </indexterm>
+        <function>ts_stat</function> ( <parameter>sqlquery</parameter> <type>text</type>
+        <optional>, <parameter>weights</parameter> <type>text</type> </optional> )
+        <returnvalue>setof record</returnvalue>
+        ( <parameter>word</parameter> <type>text</type>,
+        <parameter>ndoc</parameter> <type>integer</type>,
+        <parameter>nentry</parameter> <type>integer</type> )
+       </para>
+       <para>
+        Executes the <parameter>sqlquery</parameter>, which must return a
+        single <type>tsvector</type> column, and returns statistics about each
+        distinct lexeme contained in the data.
+        See <xref linkend="textsearch-statistics"/> for details.
+       </para>
+       <para>
+        <literal>ts_stat('SELECT vector FROM apod')</literal>
+        <returnvalue>(foo,10,15) ...</returnvalue>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+ </sect1>
diff --git a/doc/src/sgml/func/func-trigger.sgml b/doc/src/sgml/func/func-trigger.sgml
new file mode 100644
index 0000000000000..94b40adbdb84a
--- /dev/null
+++ b/doc/src/sgml/func/func-trigger.sgml
@@ -0,0 +1,135 @@
+  <sect1 id="functions-trigger">
+   <title>Trigger Functions</title>
+
+  <para>
+   While many uses of triggers involve user-written trigger functions,
+   <productname>PostgreSQL</productname> provides a few built-in trigger
+   functions that can be used directly in user-defined triggers.  These
+   are summarized in <xref linkend="builtin-triggers-table"/>.
+   (Additional built-in trigger functions exist, which implement foreign
+   key constraints and deferred index constraints.  Those are not documented
+   here since users need not use them directly.)
+  </para>
+
+  <para>
+   For more information about creating triggers, see
+   <xref linkend="sql-createtrigger"/>.
+  </para>
+
+   <table id="builtin-triggers-table">
+    <title>Built-In Trigger Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example Usage
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+       <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>suppress_redundant_updates_trigger</primary>
+        </indexterm>
+        <function>suppress_redundant_updates_trigger</function> ( )
+        <returnvalue>trigger</returnvalue>
+       </para>
+       <para>
+        Suppresses do-nothing update operations.  See below for details.
+       </para>
+       <para>
+        <literal>CREATE TRIGGER ... suppress_redundant_updates_trigger()</literal>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>tsvector_update_trigger</primary>
+        </indexterm>
+        <function>tsvector_update_trigger</function> ( )
+        <returnvalue>trigger</returnvalue>
+       </para>
+       <para>
+        Automatically updates a <type>tsvector</type> column from associated
+        plain-text document column(s).  The text search configuration to use
+        is specified by name as a trigger argument.  See
+        <xref linkend="textsearch-update-triggers"/> for details.
+       </para>
+       <para>
+        <literal>CREATE TRIGGER ... tsvector_update_trigger(tsvcol, 'pg_catalog.swedish', title, body)</literal>
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>tsvector_update_trigger_column</primary>
+        </indexterm>
+        <function>tsvector_update_trigger_column</function> ( )
+        <returnvalue>trigger</returnvalue>
+       </para>
+       <para>
+        Automatically updates a <type>tsvector</type> column from associated
+        plain-text document column(s).  The text search configuration to use
+        is taken from a <type>regconfig</type> column of the table.  See
+        <xref linkend="textsearch-update-triggers"/> for details.
+       </para>
+       <para>
+        <literal>CREATE TRIGGER ... tsvector_update_trigger_column(tsvcol, tsconfigcol, title, body)</literal>
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+   <para>
+      The <function>suppress_redundant_updates_trigger</function> function,
+      when applied as a row-level <literal>BEFORE UPDATE</literal> trigger,
+      will prevent any update that does not actually change the data in the
+      row from taking place.  This overrides the normal behavior which always
+      performs a physical row update
+      regardless of whether or not the data has changed. (This normal behavior
+      makes updates run faster, since no checking is required, and is also
+      useful in certain cases.)
+    </para>
+
+    <para>
+      Ideally, you should avoid running updates that don't actually
+      change the data in the record. Redundant updates can cost considerable
+      unnecessary time, especially if there are lots of indexes to alter,
+      and space in dead rows that will eventually have to be vacuumed.
+      However, detecting such situations in client code is not
+      always easy, or even possible, and writing expressions to detect
+      them can be error-prone. An alternative is to use
+      <function>suppress_redundant_updates_trigger</function>, which will skip
+      updates that don't change the data. You should use this with care,
+      however. The trigger takes a small but non-trivial time for each record,
+      so if most of the records affected by updates do actually change,
+      use of this trigger will make updates run slower on average.
+    </para>
+
+    <para>
+      The <function>suppress_redundant_updates_trigger</function> function can be
+      added to a table like this:
+<programlisting>
+CREATE TRIGGER z_min_update
+BEFORE UPDATE ON tablename
+FOR EACH ROW EXECUTE FUNCTION suppress_redundant_updates_trigger();
+</programlisting>
+      In most cases, you need to fire this trigger last for each row, so that
+      it does not override other triggers that might wish to alter the row.
+      Bearing in mind that triggers fire in name order, you would therefore
+      choose a trigger name that comes after the name of any other trigger
+      you might have on the table.  (Hence the <quote>z</quote> prefix in the
+      example.)
+    </para>
+  </sect1>
diff --git a/doc/src/sgml/func/func-uuid.sgml b/doc/src/sgml/func/func-uuid.sgml
new file mode 100644
index 0000000000000..65c5ddec6b7dc
--- /dev/null
+++ b/doc/src/sgml/func/func-uuid.sgml
@@ -0,0 +1,188 @@
+ <sect1 id="functions-uuid">
+  <title>UUID Functions</title>
+
+  <indexterm zone="functions-uuid">
+   <primary>UUID</primary>
+   <secondary>generating</secondary>
+  </indexterm>
+
+  <indexterm>
+   <primary>gen_random_uuid</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>uuidv4</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>uuidv7</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>uuid_extract_timestamp</primary>
+  </indexterm>
+
+  <indexterm>
+   <primary>uuid_extract_version</primary>
+  </indexterm>
+
+  <para>
+   <xref linkend="func_uuid_gen_table"/> shows the <productname>PostgreSQL</productname>
+   functions that can be used to generate UUIDs.
+  </para>
+
+  <table id="func_uuid_gen_table">
+   <title><acronym>UUID</acronym> Generation Functions</title>
+   <tgroup cols="1">
+    <thead>
+     <row>
+      <entry role="func_table_entry">
+       <para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+        </para>
+       <para>
+        Example(s)
+       </para>
+       </entry>
+     </row>
+    </thead>
+
+    <tbody>
+     <row>
+      <entry role="func_table_entry">
+       <para role="func_signature">
+        <type>gen_random_uuid</type>
+        <returnvalue>uuid</returnvalue>
+       </para>
+       <para role="func_signature">
+        <type>uuidv4</type>
+        <returnvalue>uuid</returnvalue>
+       </para>
+       <para>
+         Generate a version 4 (random) UUID.
+       </para>
+       <para>
+        <literal>gen_random_uuid()</literal>
+        <returnvalue>5b30857f-0bfa-48b5-ac0b-5c64e28078d1</returnvalue>
+       </para>
+       <para>
+        <literal>uuidv4()</literal>
+        <returnvalue>b42410ee-132f-42ee-9e4f-09a6485c95b8</returnvalue>
+       </para>
+      </entry>
+     </row>
+     <row>
+      <entry role="func_table_entry">
+       <para role="func_signature">
+        <type>uuidv7</type>
+        ( <optional> <parameter>shift</parameter> <type>interval</type> </optional> )
+        <returnvalue>uuid</returnvalue>
+       </para>
+       <para>
+        Generate a version 7 (time-ordered) UUID. The timestamp is computed using UNIX timestamp
+        with millisecond precision + sub-millisecond timestamp + random. The optional parameter
+        <parameter>shift</parameter> will shift the computed timestamp by the given <type>interval</type>.
+       </para>
+       <para>
+        <literal>uuidv7()</literal>
+        <returnvalue>019535d9-3df7-79fb-b466-fa907fa17f9e</returnvalue>
+       </para>
+      </entry>
+     </row>
+    </tbody>
+   </tgroup>
+  </table>
+
+  <note>
+   <para>
+    The <xref linkend="uuid-ossp"/> module provides additional functions that
+    implement other standard algorithms for generating UUIDs.
+   </para>
+  </note>
+
+  <para>
+   <xref linkend="func_uuid_extract_table"/> shows the <productname>PostgreSQL</productname>
+   functions that can be used to extract information from UUIDs.
+  </para>
+
+  <table id="func_uuid_extract_table">
+   <title><acronym>UUID</acronym> Extraction Functions</title>
+   <tgroup cols="1">
+    <thead>
+     <row>
+      <entry role="func_table_entry">
+       <para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para>
+       <para>
+        Example(s)
+       </para>
+      </entry>
+     </row>
+    </thead>
+
+    <tbody>
+     <row>
+      <entry role="func_table_entry">
+       <para role="func_signature">
+        <type>uuid_extract_timestamp</type>
+        ( <type>uuid</type> )
+        <returnvalue>timestamp with time zone</returnvalue>
+       </para>
+       <para>
+        Extracts a <type>timestamp with time zone</type> from UUID
+        version 1 and 7.  For other versions, this function returns null.  Note that
+        the extracted timestamp is not necessarily exactly equal to the time the
+        UUID was generated; this depends on the implementation that generated the
+        UUID.
+       </para>
+       <para>
+        <literal>uuid_extract_timestamp('019535d9-3df7-79fb-b466-&zwsp;fa907fa17f9e'::uuid)</literal>
+         <returnvalue>2025-02-23 21:46:24.503-05</returnvalue>
+       </para>
+      </entry>
+     </row>
+     <row>
+      <entry role="func_table_entry">
+       <para role="func_signature">
+        <type>uuid_extract_version</type>
+        ( <type>uuid</type> )
+        <returnvalue>smallint</returnvalue>
+       </para>
+       <para>
+        Extracts the version from a UUID of the variant described by
+        <ulink url="https://datatracker.ietf.org/doc/html/rfc9562">RFC 9562</ulink>.  For
+        other variants, this function returns null.  For example, for a UUID
+        generated by <function>gen_random_uuid</function>, this function will
+        return 4.
+       </para>
+       <para>
+        <literal>uuid_extract_version('41db1265-8bc1-4ab3-992f-&zwsp;885799a4af1d'::uuid)</literal>
+        <returnvalue>4</returnvalue>
+       </para>
+       <para>
+        <literal>uuid_extract_version('019535d9-3df7-79fb-b466-&zwsp;fa907fa17f9e'::uuid)</literal>
+        <returnvalue>7</returnvalue>
+       </para>
+      </entry>
+     </row>
+    </tbody>
+   </tgroup>
+  </table>
+
+  <para>
+   <productname>PostgreSQL</productname> also provides the usual comparison
+   operators shown in <xref linkend="functions-comparison-op-table"/> for
+   UUIDs.
+  </para>
+  <para>
+   See <xref linkend="datatype-uuid"/> for details on the data type
+   <type>uuid</type> in <productname>PostgreSQL</productname>.
+  </para>
+ </sect1>
diff --git a/doc/src/sgml/func/func-window.sgml b/doc/src/sgml/func/func-window.sgml
new file mode 100644
index 0000000000000..cce0165b9526e
--- /dev/null
+++ b/doc/src/sgml/func/func-window.sgml
@@ -0,0 +1,284 @@
+ <sect1 id="functions-window">
+  <title>Window Functions</title>
+
+  <indexterm zone="functions-window">
+   <primary>window function</primary>
+   <secondary>built-in</secondary>
+  </indexterm>
+
+  <para>
+   <firstterm>Window functions</firstterm> provide the ability to perform
+   calculations across sets of rows that are related to the current query
+   row.  See <xref linkend="tutorial-window"/> for an introduction to this
+   feature, and <xref linkend="syntax-window-functions"/> for syntax
+   details.
+  </para>
+
+  <para>
+   The built-in window functions are listed in
+   <xref linkend="functions-window-table"/>.  Note that these functions
+   <emphasis>must</emphasis> be invoked using window function syntax, i.e., an
+   <literal>OVER</literal> clause is required.
+  </para>
+
+  <para>
+   In addition to these functions, any built-in or user-defined
+   ordinary aggregate (i.e., not ordered-set or hypothetical-set aggregates)
+   can be used as a window function; see
+   <xref linkend="functions-aggregate"/> for a list of the built-in aggregates.
+   Aggregate functions act as window functions only when an <literal>OVER</literal>
+   clause follows the call; otherwise they act as plain aggregates
+   and return a single row for the entire set.
+  </para>
+
+   <table id="functions-window-table">
+    <title>General-Purpose Window Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>row_number</primary>
+        </indexterm>
+        <function>row_number</function> ()
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Returns the number of the current row within its partition, counting
+        from 1.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rank</primary>
+        </indexterm>
+        <function>rank</function> ()
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Returns the rank of the current row, with gaps; that is,
+        the <function>row_number</function> of the first row in its peer
+        group.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>dense_rank</primary>
+        </indexterm>
+        <function>dense_rank</function> ()
+        <returnvalue>bigint</returnvalue>
+       </para>
+       <para>
+        Returns the rank of the current row, without gaps; this function
+        effectively counts peer groups.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>percent_rank</primary>
+        </indexterm>
+        <function>percent_rank</function> ()
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Returns the relative rank of the current row, that is
+        (<function>rank</function> - 1) / (total partition rows - 1).
+        The value thus ranges from 0 to 1 inclusive.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>cume_dist</primary>
+        </indexterm>
+        <function>cume_dist</function> ()
+        <returnvalue>double precision</returnvalue>
+       </para>
+       <para>
+        Returns the cumulative distribution, that is (number of partition rows
+        preceding or peers with current row) / (total partition rows).
+        The value thus ranges from 1/<parameter>N</parameter> to 1.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>ntile</primary>
+        </indexterm>
+        <function>ntile</function> ( <parameter>num_buckets</parameter> <type>integer</type> )
+        <returnvalue>integer</returnvalue>
+       </para>
+       <para>
+        Returns an integer ranging from 1 to the argument value, dividing the
+        partition as equally as possible.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>lag</primary>
+        </indexterm>
+        <function>lag</function> ( <parameter>value</parameter> <type>anycompatible</type>
+          <optional>, <parameter>offset</parameter> <type>integer</type>
+          <optional>, <parameter>default</parameter> <type>anycompatible</type> </optional></optional> )
+        <returnvalue>anycompatible</returnvalue>
+       </para>
+       <para>
+        Returns <parameter>value</parameter> evaluated at
+        the row that is <parameter>offset</parameter>
+        rows before the current row within the partition; if there is no such
+        row, instead returns <parameter>default</parameter>
+        (which must be of a type compatible with
+        <parameter>value</parameter>).
+        Both <parameter>offset</parameter> and
+        <parameter>default</parameter> are evaluated
+        with respect to the current row.  If omitted,
+        <parameter>offset</parameter> defaults to 1 and
+        <parameter>default</parameter> to <literal>NULL</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>lead</primary>
+        </indexterm>
+        <function>lead</function> ( <parameter>value</parameter> <type>anycompatible</type>
+          <optional>, <parameter>offset</parameter> <type>integer</type>
+          <optional>, <parameter>default</parameter> <type>anycompatible</type> </optional></optional> )
+        <returnvalue>anycompatible</returnvalue>
+       </para>
+       <para>
+        Returns <parameter>value</parameter> evaluated at
+        the row that is <parameter>offset</parameter>
+        rows after the current row within the partition; if there is no such
+        row, instead returns <parameter>default</parameter>
+        (which must be of a type compatible with
+        <parameter>value</parameter>).
+        Both <parameter>offset</parameter> and
+        <parameter>default</parameter> are evaluated
+        with respect to the current row.  If omitted,
+        <parameter>offset</parameter> defaults to 1 and
+        <parameter>default</parameter> to <literal>NULL</literal>.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>first_value</primary>
+        </indexterm>
+        <function>first_value</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns <parameter>value</parameter> evaluated
+        at the row that is the first row of the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>last_value</primary>
+        </indexterm>
+        <function>last_value</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns <parameter>value</parameter> evaluated
+        at the row that is the last row of the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>nth_value</primary>
+        </indexterm>
+        <function>nth_value</function> ( <parameter>value</parameter> <type>anyelement</type>, <parameter>n</parameter> <type>integer</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns <parameter>value</parameter> evaluated
+        at the row that is the <parameter>n</parameter>'th
+        row of the window frame (counting from 1);
+        returns <literal>NULL</literal> if there is no such row.
+       </para></entry>
+      </row>
+     </tbody>
+    </tgroup>
+   </table>
+
+  <para>
+   All of the functions listed in
+   <xref linkend="functions-window-table"/> depend on the sort ordering
+   specified by the <literal>ORDER BY</literal> clause of the associated window
+   definition.  Rows that are not distinct when considering only the
+   <literal>ORDER BY</literal> columns are said to be <firstterm>peers</firstterm>.
+   The four ranking functions (including <function>cume_dist</function>) are
+   defined so that they give the same answer for all rows of a peer group.
+  </para>
+
+  <para>
+   Note that <function>first_value</function>, <function>last_value</function>, and
+   <function>nth_value</function> consider only the rows within the <quote>window
+   frame</quote>, which by default contains the rows from the start of the
+   partition through the last peer of the current row.  This is
+   likely to give unhelpful results for <function>last_value</function> and
+   sometimes also <function>nth_value</function>.  You can redefine the frame by
+   adding a suitable frame specification (<literal>RANGE</literal>,
+   <literal>ROWS</literal> or <literal>GROUPS</literal>) to
+   the <literal>OVER</literal> clause.
+   See <xref linkend="syntax-window-functions"/> for more information
+   about frame specifications.
+  </para>
+
+  <para>
+   When an aggregate function is used as a window function, it aggregates
+   over the rows within the current row's window frame.
+   An aggregate used with <literal>ORDER BY</literal> and the default window frame
+   definition produces a <quote>running sum</quote> type of behavior, which may or
+   may not be what's wanted.  To obtain
+   aggregation over the whole partition, omit <literal>ORDER BY</literal> or use
+   <literal>ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING</literal>.
+   Other frame specifications can be used to obtain other effects.
+  </para>
+
+  <note>
+   <para>
+    The SQL standard defines a <literal>RESPECT NULLS</literal> or
+    <literal>IGNORE NULLS</literal> option for <function>lead</function>, <function>lag</function>,
+    <function>first_value</function>, <function>last_value</function>, and
+    <function>nth_value</function>.  This is not implemented in
+    <productname>PostgreSQL</productname>: the behavior is always the
+    same as the standard's default, namely <literal>RESPECT NULLS</literal>.
+    Likewise, the standard's <literal>FROM FIRST</literal> or <literal>FROM LAST</literal>
+    option for <function>nth_value</function> is not implemented: only the
+    default <literal>FROM FIRST</literal> behavior is supported.  (You can achieve
+    the result of <literal>FROM LAST</literal> by reversing the <literal>ORDER BY</literal>
+    ordering.)
+   </para>
+  </note>
+
+ </sect1>
diff --git a/doc/src/sgml/func/func-xml.sgml b/doc/src/sgml/func/func-xml.sgml
new file mode 100644
index 0000000000000..21f34467a4f8a
--- /dev/null
+++ b/doc/src/sgml/func/func-xml.sgml
@@ -0,0 +1,1283 @@
+ <sect1 id="functions-xml">
+
+  <title>XML Functions</title>
+
+  <indexterm>
+   <primary>XML Functions</primary>
+  </indexterm>
+
+  <para>
+   The functions and function-like expressions described in this
+   section operate on values of type <type>xml</type>.  See <xref
+   linkend="datatype-xml"/> for information about the <type>xml</type>
+   type.  The function-like expressions <function>xmlparse</function>
+   and <function>xmlserialize</function> for converting to and from
+   type <type>xml</type> are documented there, not in this section.
+  </para>
+
+  <para>
+   Use of most of these functions
+   requires <productname>PostgreSQL</productname> to have been built
+   with <command>configure --with-libxml</command>.
+  </para>
+
+  <sect2 id="functions-producing-xml">
+   <title>Producing XML Content</title>
+
+   <para>
+    A set of functions and function-like expressions is available for
+    producing XML content from SQL data.  As such, they are
+    particularly suitable for formatting query results into XML
+    documents for processing in client applications.
+   </para>
+
+  <sect3 id="functions-producing-xml-xmltext">
+    <title><literal>xmltext</literal></title>
+
+    <indexterm>
+     <primary>xmltext</primary>
+    </indexterm>
+
+<synopsis>
+<function>xmltext</function> ( <type>text</type> ) <returnvalue>xml</returnvalue>
+</synopsis>
+
+    <para>
+     The function <function>xmltext</function> returns an XML value with a single
+     text node containing the input argument as its content. Predefined entities
+     like ampersand (<literal><![CDATA[&]]></literal>), left and right angle brackets
+     (<literal><![CDATA[< >]]></literal>), and quotation marks (<literal><![CDATA[""]]></literal>)
+     are escaped.
+    </para>
+
+    <para>
+     Example:
+<screen><![CDATA[
+SELECT xmltext('< foo & bar >');
+         xmltext
+-------------------------
+ &lt; foo &amp; bar &gt;
+]]></screen>
+    </para>
+   </sect3>
+
+   <sect3 id="functions-producing-xml-xmlcomment">
+    <title><literal>xmlcomment</literal></title>
+
+    <indexterm>
+     <primary>xmlcomment</primary>
+    </indexterm>
+
+<synopsis>
+<function>xmlcomment</function> ( <type>text</type> ) <returnvalue>xml</returnvalue>
+</synopsis>
+
+    <para>
+     The function <function>xmlcomment</function> creates an XML value
+     containing an XML comment with the specified text as content.
+     The text cannot contain <quote><literal>--</literal></quote> or end with a
+     <quote><literal>-</literal></quote>, otherwise the resulting construct
+     would not be a valid XML comment.
+     If the argument is null, the result is null.
+    </para>
+
+    <para>
+     Example:
+<screen><![CDATA[
+SELECT xmlcomment('hello');
+
+  xmlcomment
+--------------
+ <!--hello-->
+]]></screen>
+    </para>
+   </sect3>
+
+   <sect3 id="functions-producing-xml-xmlconcat">
+    <title><literal>xmlconcat</literal></title>
+
+    <indexterm>
+     <primary>xmlconcat</primary>
+    </indexterm>
+
+<synopsis>
+<function>xmlconcat</function> ( <type>xml</type> <optional>, ...</optional> ) <returnvalue>xml</returnvalue>
+</synopsis>
+
+    <para>
+     The function <function>xmlconcat</function> concatenates a list
+     of individual XML values to create a single value containing an
+     XML content fragment.  Null values are omitted; the result is
+     only null if there are no nonnull arguments.
+    </para>
+
+    <para>
+     Example:
+<screen><![CDATA[
+SELECT xmlconcat('<abc/>', '<bar>foo</bar>');
+
+      xmlconcat
+----------------------
+ <abc/><bar>foo</bar>
+]]></screen>
+    </para>
+
+    <para>
+     XML declarations, if present, are combined as follows.  If all
+     argument values have the same XML version declaration, that
+     version is used in the result, else no version is used.  If all
+     argument values have the standalone declaration value
+     <quote>yes</quote>, then that value is used in the result.  If
+     all argument values have a standalone declaration value and at
+     least one is <quote>no</quote>, then that is used in the result.
+     Else the result will have no standalone declaration.  If the
+     result is determined to require a standalone declaration but no
+     version declaration, a version declaration with version 1.0 will
+     be used because XML requires an XML declaration to contain a
+     version declaration.  Encoding declarations are ignored and
+     removed in all cases.
+    </para>
+
+    <para>
+     Example:
+<screen><![CDATA[
+SELECT xmlconcat('<?xml version="1.1"?><foo/>', '<?xml version="1.1" standalone="no"?><bar/>');
+
+             xmlconcat
+-----------------------------------
+ <?xml version="1.1"?><foo/><bar/>
+]]></screen>
+    </para>
+   </sect3>
+
+   <sect3 id="functions-producing-xml-xmlelement">
+    <title><literal>xmlelement</literal></title>
+
+   <indexterm>
+    <primary>xmlelement</primary>
+   </indexterm>
+
+<synopsis>
+<function>xmlelement</function> ( <literal>NAME</literal> <replaceable>name</replaceable> <optional>, <literal>XMLATTRIBUTES</literal> ( <replaceable>attvalue</replaceable> <optional> <literal>AS</literal> <replaceable>attname</replaceable> </optional> <optional>, ...</optional> ) </optional> <optional>, <replaceable>content</replaceable> <optional>, ...</optional></optional> ) <returnvalue>xml</returnvalue>
+</synopsis>
+
+    <para>
+     The <function>xmlelement</function> expression produces an XML
+     element with the given name, attributes, and content.
+     The <replaceable>name</replaceable>
+     and <replaceable>attname</replaceable> items shown in the syntax are
+     simple identifiers, not values.  The <replaceable>attvalue</replaceable>
+     and <replaceable>content</replaceable> items are expressions, which can
+     yield any <productname>PostgreSQL</productname> data type.  The
+     argument(s) within <literal>XMLATTRIBUTES</literal> generate attributes
+     of the XML element; the <replaceable>content</replaceable> value(s) are
+     concatenated to form its content.
+    </para>
+
+    <para>
+     Examples:
+<screen><![CDATA[
+SELECT xmlelement(name foo);
+
+ xmlelement
+------------
+ <foo/>
+
+SELECT xmlelement(name foo, xmlattributes('xyz' as bar));
+
+    xmlelement
+------------------
+ <foo bar="xyz"/>
+
+SELECT xmlelement(name foo, xmlattributes(current_date as bar), 'cont', 'ent');
+
+             xmlelement
+-------------------------------------
+ <foo bar="2007-01-26">content</foo>
+]]></screen>
+    </para>
+
+    <para>
+     Element and attribute names that are not valid XML names are
+     escaped by replacing the offending characters by the sequence
+     <literal>_x<replaceable>HHHH</replaceable>_</literal>, where
+     <replaceable>HHHH</replaceable> is the character's Unicode
+     codepoint in hexadecimal notation.  For example:
+<screen><![CDATA[
+SELECT xmlelement(name "foo$bar", xmlattributes('xyz' as "a&b"));
+
+            xmlelement
+----------------------------------
+ <foo_x0024_bar a_x0026_b="xyz"/>
+]]></screen>
+    </para>
+
+    <para>
+     An explicit attribute name need not be specified if the attribute
+     value is a column reference, in which case the column's name will
+     be used as the attribute name by default.  In other cases, the
+     attribute must be given an explicit name.  So this example is
+     valid:
+<screen>
+CREATE TABLE test (a xml, b xml);
+SELECT xmlelement(name test, xmlattributes(a, b)) FROM test;
+</screen>
+     But these are not:
+<screen>
+SELECT xmlelement(name test, xmlattributes('constant'), a, b) FROM test;
+SELECT xmlelement(name test, xmlattributes(func(a, b))) FROM test;
+</screen>
+    </para>
+
+    <para>
+     Element content, if specified, will be formatted according to
+     its data type.  If the content is itself of type <type>xml</type>,
+     complex XML documents can be constructed.  For example:
+<screen><![CDATA[
+SELECT xmlelement(name foo, xmlattributes('xyz' as bar),
+                            xmlelement(name abc),
+                            xmlcomment('test'),
+                            xmlelement(name xyz));
+
+                  xmlelement
+----------------------------------------------
+ <foo bar="xyz"><abc/><!--test--><xyz/></foo>
+]]></screen>
+
+     Content of other types will be formatted into valid XML character
+     data.  This means in particular that the characters &lt;, &gt;,
+     and &amp; will be converted to entities.  Binary data (data type
+     <type>bytea</type>) will be represented in base64 or hex
+     encoding, depending on the setting of the configuration parameter
+     <xref linkend="guc-xmlbinary"/>.  The particular behavior for
+     individual data types is expected to evolve in order to align the
+     PostgreSQL mappings with those specified in SQL:2006 and later,
+     as discussed in <xref linkend="functions-xml-limits-casts"/>.
+    </para>
+   </sect3>
+
+   <sect3 id="functions-producing-xml-xmlforest">
+    <title><literal>xmlforest</literal></title>
+
+   <indexterm>
+    <primary>xmlforest</primary>
+   </indexterm>
+
+<synopsis>
+<function>xmlforest</function> ( <replaceable>content</replaceable> <optional> <literal>AS</literal> <replaceable>name</replaceable> </optional> <optional>, ...</optional> ) <returnvalue>xml</returnvalue>
+</synopsis>
+
+    <para>
+     The <function>xmlforest</function> expression produces an XML
+     forest (sequence) of elements using the given names and content.
+     As for <function>xmlelement</function>,
+     each <replaceable>name</replaceable> must be a simple identifier, while
+     the <replaceable>content</replaceable> expressions can have any data
+     type.
+    </para>
+
+    <para>
+     Examples:
+<screen>
+SELECT xmlforest('abc' AS foo, 123 AS bar);
+
+          xmlforest
+------------------------------
+ &lt;foo&gt;abc&lt;/foo&gt;&lt;bar&gt;123&lt;/bar&gt;
+
+
+SELECT xmlforest(table_name, column_name)
+FROM information_schema.columns
+WHERE table_schema = 'pg_catalog';
+
+                                xmlforest
+------------------------------------&zwsp;-----------------------------------
+ &lt;table_name&gt;pg_authid&lt;/table_name&gt;&zwsp;&lt;column_name&gt;rolname&lt;/column_name&gt;
+ &lt;table_name&gt;pg_authid&lt;/table_name&gt;&zwsp;&lt;column_name&gt;rolsuper&lt;/column_name&gt;
+ ...
+</screen>
+
+     As seen in the second example, the element name can be omitted if
+     the content value is a column reference, in which case the column
+     name is used by default.  Otherwise, a name must be specified.
+    </para>
+
+    <para>
+     Element names that are not valid XML names are escaped as shown
+     for <function>xmlelement</function> above.  Similarly, content
+     data is escaped to make valid XML content, unless it is already
+     of type <type>xml</type>.
+    </para>
+
+    <para>
+     Note that XML forests are not valid XML documents if they consist
+     of more than one element, so it might be useful to wrap
+     <function>xmlforest</function> expressions in
+     <function>xmlelement</function>.
+    </para>
+   </sect3>
+
+   <sect3 id="functions-producing-xml-xmlpi">
+    <title><literal>xmlpi</literal></title>
+
+   <indexterm>
+    <primary>xmlpi</primary>
+   </indexterm>
+
+<synopsis>
+<function>xmlpi</function> ( <literal>NAME</literal> <replaceable>name</replaceable> <optional>, <replaceable>content</replaceable> </optional> ) <returnvalue>xml</returnvalue>
+</synopsis>
+
+    <para>
+     The <function>xmlpi</function> expression creates an XML
+     processing instruction.
+     As for <function>xmlelement</function>,
+     the <replaceable>name</replaceable> must be a simple identifier, while
+     the <replaceable>content</replaceable> expression can have any data type.
+     The <replaceable>content</replaceable>, if present, must not contain the
+     character sequence <literal>?&gt;</literal>.
+    </para>
+
+    <para>
+     Example:
+<screen><![CDATA[
+SELECT xmlpi(name php, 'echo "hello world";');
+
+            xmlpi
+-----------------------------
+ <?php echo "hello world";?>
+]]></screen>
+    </para>
+   </sect3>
+
+   <sect3 id="functions-producing-xml-xmlroot">
+    <title><literal>xmlroot</literal></title>
+
+   <indexterm>
+    <primary>xmlroot</primary>
+   </indexterm>
+
+<synopsis>
+<function>xmlroot</function> ( <type>xml</type>, <literal>VERSION</literal> {<type>text</type>|<literal>NO VALUE</literal>} <optional>, <literal>STANDALONE</literal> {<literal>YES</literal>|<literal>NO</literal>|<literal>NO VALUE</literal>} </optional> ) <returnvalue>xml</returnvalue>
+</synopsis>
+
+    <para>
+     The <function>xmlroot</function> expression alters the properties
+     of the root node of an XML value.  If a version is specified,
+     it replaces the value in the root node's version declaration; if a
+     standalone setting is specified, it replaces the value in the
+     root node's standalone declaration.
+    </para>
+
+    <para>
+<screen><![CDATA[
+SELECT xmlroot(xmlparse(document '<?xml version="1.1"?><content>abc</content>'),
+               version '1.0', standalone yes);
+
+                xmlroot
+----------------------------------------
+ <?xml version="1.0" standalone="yes"?>
+ <content>abc</content>
+]]></screen>
+    </para>
+   </sect3>
+
+   <sect3 id="functions-xml-xmlagg">
+    <title><literal>xmlagg</literal></title>
+
+    <indexterm>
+     <primary>xmlagg</primary>
+    </indexterm>
+
+<synopsis>
+<function>xmlagg</function> ( <type>xml</type> ) <returnvalue>xml</returnvalue>
+</synopsis>
+
+    <para>
+     The function <function>xmlagg</function> is, unlike the other
+     functions described here, an aggregate function.  It concatenates the
+     input values to the aggregate function call,
+     much like <function>xmlconcat</function> does, except that concatenation
+     occurs across rows rather than across expressions in a single row.
+     See <xref linkend="functions-aggregate"/> for additional information
+     about aggregate functions.
+    </para>
+
+    <para>
+     Example:
+<screen><![CDATA[
+CREATE TABLE test (y int, x xml);
+INSERT INTO test VALUES (1, '<foo>abc</foo>');
+INSERT INTO test VALUES (2, '<bar/>');
+SELECT xmlagg(x) FROM test;
+        xmlagg
+----------------------
+ <foo>abc</foo><bar/>
+]]></screen>
+    </para>
+
+    <para>
+     To determine the order of the concatenation, an <literal>ORDER BY</literal>
+     clause may be added to the aggregate call as described in
+     <xref linkend="syntax-aggregates"/>. For example:
+
+<screen><![CDATA[
+SELECT xmlagg(x ORDER BY y DESC) FROM test;
+        xmlagg
+----------------------
+ <bar/><foo>abc</foo>
+]]></screen>
+    </para>
+
+    <para>
+     The following non-standard approach used to be recommended
+     in previous versions, and may still be useful in specific
+     cases:
+
+<screen><![CDATA[
+SELECT xmlagg(x) FROM (SELECT * FROM test ORDER BY y DESC) AS tab;
+        xmlagg
+----------------------
+ <bar/><foo>abc</foo>
+]]></screen>
+    </para>
+   </sect3>
+   </sect2>
+
+   <sect2 id="functions-xml-predicates">
+    <title>XML Predicates</title>
+
+    <para>
+     The expressions described in this section check properties
+     of <type>xml</type> values.
+    </para>
+
+   <sect3 id="functions-producing-xml-is-document">
+    <title><literal>IS DOCUMENT</literal></title>
+
+    <indexterm>
+     <primary>IS DOCUMENT</primary>
+    </indexterm>
+
+<synopsis>
+<type>xml</type> <literal>IS DOCUMENT</literal> <returnvalue>boolean</returnvalue>
+</synopsis>
+
+    <para>
+     The expression <literal>IS DOCUMENT</literal> returns true if the
+     argument XML value is a proper XML document, false if it is not
+     (that is, it is a content fragment), or null if the argument is
+     null.  See <xref linkend="datatype-xml"/> about the difference
+     between documents and content fragments.
+    </para>
+   </sect3>
+
+   <sect3 id="functions-producing-xml-is-not-document">
+    <title><literal>IS NOT DOCUMENT</literal></title>
+
+    <indexterm>
+     <primary>IS NOT DOCUMENT</primary>
+    </indexterm>
+
+<synopsis>
+<type>xml</type> <literal>IS NOT DOCUMENT</literal> <returnvalue>boolean</returnvalue>
+</synopsis>
+
+    <para>
+     The expression <literal>IS NOT DOCUMENT</literal> returns false if the
+     argument XML value is a proper XML document, true if it is not (that is,
+     it is a content fragment), or null if the argument is null.
+    </para>
+   </sect3>
+
+   <sect3 id="xml-exists">
+    <title><literal>XMLEXISTS</literal></title>
+
+    <indexterm>
+     <primary>XMLEXISTS</primary>
+    </indexterm>
+
+<synopsis>
+<function>XMLEXISTS</function> ( <type>text</type> <literal>PASSING</literal> <optional><literal>BY</literal> {<literal>REF</literal>|<literal>VALUE</literal>}</optional> <type>xml</type> <optional><literal>BY</literal> {<literal>REF</literal>|<literal>VALUE</literal>}</optional> ) <returnvalue>boolean</returnvalue>
+</synopsis>
+
+    <para>
+     The function <function>xmlexists</function> evaluates an XPath 1.0
+     expression (the first argument), with the passed XML value as its context
+     item.  The function returns false if the result of that evaluation
+     yields an empty node-set, true if it yields any other value.  The
+     function returns null if any argument is null.  A nonnull value
+     passed as the context item must be an XML document, not a content
+     fragment or any non-XML value.
+    </para>
+
+    <para>
+     Example:
+     <screen><![CDATA[
+SELECT xmlexists('//town[text() = ''Toronto'']' PASSING BY VALUE '<towns><town>Toronto</town><town>Ottawa</town></towns>');
+
+ xmlexists
+------------
+ t
+(1 row)
+]]></screen>
+    </para>
+
+    <para>
+     The <literal>BY REF</literal> and <literal>BY VALUE</literal> clauses
+     are accepted in <productname>PostgreSQL</productname>, but are ignored,
+     as discussed in <xref linkend="functions-xml-limits-postgresql"/>.
+    </para>
+
+    <para>
+     In the SQL standard, the <function>xmlexists</function> function
+     evaluates an expression in the XML Query language,
+     but <productname>PostgreSQL</productname> allows only an XPath 1.0
+     expression, as discussed in
+     <xref linkend="functions-xml-limits-xpath1"/>.
+    </para>
+   </sect3>
+
+   <sect3 id="xml-is-well-formed">
+    <title><literal>xml_is_well_formed</literal></title>
+
+    <indexterm>
+     <primary>xml_is_well_formed</primary>
+    </indexterm>
+
+    <indexterm>
+     <primary>xml_is_well_formed_document</primary>
+    </indexterm>
+
+    <indexterm>
+     <primary>xml_is_well_formed_content</primary>
+    </indexterm>
+
+<synopsis>
+<function>xml_is_well_formed</function> ( <type>text</type> ) <returnvalue>boolean</returnvalue>
+<function>xml_is_well_formed_document</function> ( <type>text</type> ) <returnvalue>boolean</returnvalue>
+<function>xml_is_well_formed_content</function> ( <type>text</type> ) <returnvalue>boolean</returnvalue>
+</synopsis>
+
+    <para>
+     These functions check whether a <type>text</type> string represents
+     well-formed XML, returning a Boolean result.
+     <function>xml_is_well_formed_document</function> checks for a well-formed
+     document, while <function>xml_is_well_formed_content</function> checks
+     for well-formed content.  <function>xml_is_well_formed</function> does
+     the former if the <xref linkend="guc-xmloption"/> configuration
+     parameter is set to <literal>DOCUMENT</literal>, or the latter if it is set to
+     <literal>CONTENT</literal>.  This means that
+     <function>xml_is_well_formed</function> is useful for seeing whether
+     a simple cast to type <type>xml</type> will succeed, whereas the other two
+     functions are useful for seeing whether the corresponding variants of
+     <function>XMLPARSE</function> will succeed.
+    </para>
+
+    <para>
+     Examples:
+
+<screen><![CDATA[
+SET xmloption TO DOCUMENT;
+SELECT xml_is_well_formed('<>');
+ xml_is_well_formed
+--------------------
+ f
+(1 row)
+
+SELECT xml_is_well_formed('<abc/>');
+ xml_is_well_formed
+--------------------
+ t
+(1 row)
+
+SET xmloption TO CONTENT;
+SELECT xml_is_well_formed('abc');
+ xml_is_well_formed
+--------------------
+ t
+(1 row)
+
+SELECT xml_is_well_formed_document('<pg:foo xmlns:pg="http://postgresql.org/stuff">bar</pg:foo>');
+ xml_is_well_formed_document
+-----------------------------
+ t
+(1 row)
+
+SELECT xml_is_well_formed_document('<pg:foo xmlns:pg="http://postgresql.org/stuff">bar</my:foo>');
+ xml_is_well_formed_document
+-----------------------------
+ f
+(1 row)
+]]></screen>
+
+     The last example shows that the checks include whether
+     namespaces are correctly matched.
+    </para>
+   </sect3>
+  </sect2>
+
+  <sect2 id="functions-xml-processing">
+   <title>Processing XML</title>
+
+   <para>
+    To process values of data type <type>xml</type>, PostgreSQL offers
+    the functions <function>xpath</function> and
+    <function>xpath_exists</function>, which evaluate XPath 1.0
+    expressions, and the <function>XMLTABLE</function>
+    table function.
+   </para>
+
+   <sect3 id="functions-xml-processing-xpath">
+    <title><literal>xpath</literal></title>
+
+    <indexterm>
+     <primary>XPath</primary>
+    </indexterm>
+
+<synopsis>
+<function>xpath</function> ( <parameter>xpath</parameter> <type>text</type>, <parameter>xml</parameter> <type>xml</type> <optional>, <parameter>nsarray</parameter> <type>text[]</type> </optional> ) <returnvalue>xml[]</returnvalue>
+</synopsis>
+
+    <para>
+     The function <function>xpath</function> evaluates the XPath 1.0
+     expression <parameter>xpath</parameter> (given as text)
+     against the XML value
+     <parameter>xml</parameter>.  It returns an array of XML values
+     corresponding to the node-set produced by the XPath expression.
+     If the XPath expression returns a scalar value rather than a node-set,
+     a single-element array is returned.
+    </para>
+
+    <para>
+     The second argument must be a well formed XML document. In particular,
+     it must have a single root node element.
+    </para>
+
+    <para>
+     The optional third argument of the function is an array of namespace
+     mappings.  This array should be a two-dimensional <type>text</type> array with
+     the length of the second axis being equal to 2 (i.e., it should be an
+     array of arrays, each of which consists of exactly 2 elements).
+     The first element of each array entry is the namespace name (alias), the
+     second the namespace URI. It is not required that aliases provided in
+     this array be the same as those being used in the XML document itself (in
+     other words, both in the XML document and in the <function>xpath</function>
+     function context, aliases are <emphasis>local</emphasis>).
+    </para>
+
+    <para>
+     Example:
+<screen><![CDATA[
+SELECT xpath('/my:a/text()', '<my:a xmlns:my="http://example.com">test</my:a>',
+             ARRAY[ARRAY['my', 'http://example.com']]);
+
+ xpath
+--------
+ {test}
+(1 row)
+]]></screen>
+    </para>
+
+    <para>
+     To deal with default (anonymous) namespaces, do something like this:
+<screen><![CDATA[
+SELECT xpath('//mydefns:b/text()', '<a xmlns="http://example.com"><b>test</b></a>',
+             ARRAY[ARRAY['mydefns', 'http://example.com']]);
+
+ xpath
+--------
+ {test}
+(1 row)
+]]></screen>
+    </para>
+   </sect3>
+
+   <sect3 id="functions-xml-processing-xpath-exists">
+    <title><literal>xpath_exists</literal></title>
+
+    <indexterm>
+     <primary>xpath_exists</primary>
+    </indexterm>
+
+<synopsis>
+<function>xpath_exists</function> ( <parameter>xpath</parameter> <type>text</type>, <parameter>xml</parameter> <type>xml</type> <optional>, <parameter>nsarray</parameter> <type>text[]</type> </optional> ) <returnvalue>boolean</returnvalue>
+</synopsis>
+
+    <para>
+     The function <function>xpath_exists</function> is a specialized form
+     of the <function>xpath</function> function.  Instead of returning the
+     individual XML values that satisfy the XPath 1.0 expression, this function
+     returns a Boolean indicating whether the query was satisfied or not
+     (specifically, whether it produced any value other than an empty node-set).
+     This function is equivalent to the <literal>XMLEXISTS</literal> predicate,
+     except that it also offers support for a namespace mapping argument.
+    </para>
+
+    <para>
+     Example:
+<screen><![CDATA[
+SELECT xpath_exists('/my:a/text()', '<my:a xmlns:my="http://example.com">test</my:a>',
+                     ARRAY[ARRAY['my', 'http://example.com']]);
+
+ xpath_exists
+--------------
+ t
+(1 row)
+]]></screen>
+    </para>
+   </sect3>
+
+   <sect3 id="functions-xml-processing-xmltable">
+    <title><literal>xmltable</literal></title>
+
+    <indexterm>
+     <primary>xmltable</primary>
+    </indexterm>
+
+    <indexterm zone="functions-xml-processing-xmltable">
+     <primary>table function</primary>
+     <secondary>XMLTABLE</secondary>
+    </indexterm>
+
+<synopsis>
+<function>XMLTABLE</function> (
+    <optional> <literal>XMLNAMESPACES</literal> ( <replaceable>namespace_uri</replaceable> <literal>AS</literal> <replaceable>namespace_name</replaceable> <optional>, ...</optional> ), </optional>
+    <replaceable>row_expression</replaceable> <literal>PASSING</literal> <optional><literal>BY</literal> {<literal>REF</literal>|<literal>VALUE</literal>}</optional> <replaceable>document_expression</replaceable> <optional><literal>BY</literal> {<literal>REF</literal>|<literal>VALUE</literal>}</optional>
+    <literal>COLUMNS</literal> <replaceable>name</replaceable> { <replaceable>type</replaceable> <optional><literal>PATH</literal> <replaceable>column_expression</replaceable></optional> <optional><literal>DEFAULT</literal> <replaceable>default_expression</replaceable></optional> <optional><literal>NOT NULL</literal> | <literal>NULL</literal></optional>
+                  | <literal>FOR ORDINALITY</literal> }
+            <optional>, ...</optional>
+) <returnvalue>setof record</returnvalue>
+</synopsis>
+
+    <para>
+     The <function>xmltable</function> expression produces a table based
+     on an XML value, an XPath filter to extract rows, and a
+     set of column definitions.
+     Although it syntactically resembles a function, it can only appear
+     as a table in a query's <literal>FROM</literal> clause.
+    </para>
+
+    <para>
+     The optional <literal>XMLNAMESPACES</literal> clause gives a
+     comma-separated list of namespace definitions, where
+     each <replaceable>namespace_uri</replaceable> is a <type>text</type>
+     expression and each <replaceable>namespace_name</replaceable> is a simple
+     identifier.  It specifies the XML namespaces used in the document and
+     their aliases. A default namespace specification is not currently
+     supported.
+    </para>
+
+    <para>
+     The required <replaceable>row_expression</replaceable> argument is an
+     XPath 1.0 expression (given as <type>text</type>) that is evaluated,
+     passing the XML value <replaceable>document_expression</replaceable> as
+     its context item, to obtain a set of XML nodes. These nodes are what
+     <function>xmltable</function> transforms into output rows. No rows
+     will be produced if the <replaceable>document_expression</replaceable>
+     is null, nor if the <replaceable>row_expression</replaceable> produces
+     an empty node-set or any value other than a node-set.
+    </para>
+
+    <para>
+     <replaceable>document_expression</replaceable> provides the context
+     item for the <replaceable>row_expression</replaceable>. It must be a
+     well-formed XML document; fragments/forests are not accepted.
+     The <literal>BY REF</literal> and <literal>BY VALUE</literal> clauses
+     are accepted but ignored, as discussed in
+     <xref linkend="functions-xml-limits-postgresql"/>.
+    </para>
+
+    <para>
+     In the SQL standard, the <function>xmltable</function> function
+     evaluates expressions in the XML Query language,
+     but <productname>PostgreSQL</productname> allows only XPath 1.0
+     expressions, as discussed in
+     <xref linkend="functions-xml-limits-xpath1"/>.
+    </para>
+
+    <para>
+     The required <literal>COLUMNS</literal> clause specifies the
+     column(s) that will be produced in the output table.
+     See the syntax summary above for the format.
+     A name is required for each column, as is a data type
+     (unless <literal>FOR ORDINALITY</literal> is specified, in which case
+     type <type>integer</type> is implicit).  The path, default and
+     nullability clauses are optional.
+    </para>
+
+    <para>
+     A column marked <literal>FOR ORDINALITY</literal> will be populated
+     with row numbers, starting with 1, in the order of nodes retrieved from
+     the <replaceable>row_expression</replaceable>'s result node-set.
+     At most one column may be marked <literal>FOR ORDINALITY</literal>.
+    </para>
+
+    <note>
+     <para>
+      XPath 1.0 does not specify an order for nodes in a node-set, so code
+      that relies on a particular order of the results will be
+      implementation-dependent.  Details can be found in
+      <xref linkend="xml-xpath-1-specifics"/>.
+     </para>
+    </note>
+
+    <para>
+     The <replaceable>column_expression</replaceable> for a column is an
+     XPath 1.0 expression that is evaluated for each row, with the current
+     node from the <replaceable>row_expression</replaceable> result as its
+     context item, to find the value of the column.  If
+     no <replaceable>column_expression</replaceable> is given, then the
+     column name is used as an implicit path.
+    </para>
+
+    <para>
+     If a column's XPath expression returns a non-XML value (which is limited
+     to string, boolean, or double in XPath 1.0) and the column has a
+     PostgreSQL type other than <type>xml</type>, the column will be set
+     as if by assigning the value's string representation to the PostgreSQL
+     type.  (If the value is a boolean, its string representation is taken
+     to be <literal>1</literal> or <literal>0</literal> if the output
+     column's type category is numeric, otherwise <literal>true</literal> or
+     <literal>false</literal>.)
+    </para>
+
+    <para>
+     If a column's XPath expression returns a non-empty set of XML nodes
+     and the column's PostgreSQL type is <type>xml</type>, the column will
+     be assigned the expression result exactly, if it is of document or
+     content form.
+     <footnote>
+      <para>
+       A result containing more than one element node at the top level, or
+       non-whitespace text outside of an element, is an example of content form.
+       An XPath result can be of neither form, for example if it returns an
+       attribute node selected from the element that contains it. Such a result
+       will be put into content form with each such disallowed node replaced by
+       its string value, as defined for the XPath 1.0
+       <function>string</function> function.
+      </para>
+     </footnote>
+    </para>
+
+    <para>
+     A non-XML result assigned to an <type>xml</type> output column produces
+     content, a single text node with the string value of the result.
+     An XML result assigned to a column of any other type may not have more than
+     one node, or an error is raised. If there is exactly one node, the column
+     will be set as if by assigning the node's string
+     value (as defined for the XPath 1.0 <function>string</function> function)
+     to the PostgreSQL type.
+    </para>
+
+    <para>
+     The string value of an XML element is the concatenation, in document order,
+     of all text nodes contained in that element and its descendants. The string
+     value of an element with no descendant text nodes is an
+     empty string (not <literal>NULL</literal>).
+     Any <literal>xsi:nil</literal> attributes are ignored.
+     Note that the whitespace-only <literal>text()</literal> node between two non-text
+     elements is preserved, and that leading whitespace on a <literal>text()</literal>
+     node is not flattened.
+     The XPath 1.0 <function>string</function> function may be consulted for the
+     rules defining the string value of other XML node types and non-XML values.
+    </para>
+
+    <para>
+     The conversion rules presented here are not exactly those of the SQL
+     standard, as discussed in <xref linkend="functions-xml-limits-casts"/>.
+    </para>
+
+    <para>
+     If the path expression returns an empty node-set
+     (typically, when it does not match)
+     for a given row, the column will be set to <literal>NULL</literal>, unless
+     a <replaceable>default_expression</replaceable> is specified; then the
+     value resulting from evaluating that expression is used.
+    </para>
+
+    <para>
+     A <replaceable>default_expression</replaceable>, rather than being
+     evaluated immediately when <function>xmltable</function> is called,
+     is evaluated each time a default is needed for the column.
+     If the expression qualifies as stable or immutable, the repeat
+     evaluation may be skipped.
+     This means that you can usefully use volatile functions like
+     <function>nextval</function> in
+     <replaceable>default_expression</replaceable>.
+    </para>
+
+    <para>
+     Columns may be marked <literal>NOT NULL</literal>. If the
+     <replaceable>column_expression</replaceable> for a <literal>NOT
+     NULL</literal> column does not match anything and there is
+     no <literal>DEFAULT</literal> or
+     the <replaceable>default_expression</replaceable> also evaluates to null,
+     an error is reported.
+    </para>
+
+    <para>
+     Examples:
+  <screen><![CDATA[
+CREATE TABLE xmldata AS SELECT
+xml $$
+<ROWS>
+  <ROW id="1">
+    <COUNTRY_ID>AU</COUNTRY_ID>
+    <COUNTRY_NAME>Australia</COUNTRY_NAME>
+  </ROW>
+  <ROW id="5">
+    <COUNTRY_ID>JP</COUNTRY_ID>
+    <COUNTRY_NAME>Japan</COUNTRY_NAME>
+    <PREMIER_NAME>Shinzo Abe</PREMIER_NAME>
+    <SIZE unit="sq_mi">145935</SIZE>
+  </ROW>
+  <ROW id="6">
+    <COUNTRY_ID>SG</COUNTRY_ID>
+    <COUNTRY_NAME>Singapore</COUNTRY_NAME>
+    <SIZE unit="sq_km">697</SIZE>
+  </ROW>
+</ROWS>
+$$ AS data;
+
+SELECT xmltable.*
+  FROM xmldata,
+       XMLTABLE('//ROWS/ROW'
+                PASSING data
+                COLUMNS id int PATH '@id',
+                        ordinality FOR ORDINALITY,
+                        "COUNTRY_NAME" text,
+                        country_id text PATH 'COUNTRY_ID',
+                        size_sq_km float PATH 'SIZE[@unit = "sq_km"]',
+                        size_other text PATH
+                             'concat(SIZE[@unit!="sq_km"], " ", SIZE[@unit!="sq_km"]/@unit)',
+                        premier_name text PATH 'PREMIER_NAME' DEFAULT 'not specified');
+
+ id | ordinality | COUNTRY_NAME | country_id | size_sq_km |  size_other  | premier_name
+----+------------+--------------+------------+------------+--------------+---------------
+  1 |          1 | Australia    | AU         |            |              | not specified
+  5 |          2 | Japan        | JP         |            | 145935 sq_mi | Shinzo Abe
+  6 |          3 | Singapore    | SG         |        697 |              | not specified
+]]></screen>
+
+     The following example shows concatenation of multiple text() nodes,
+     usage of the column name as XPath filter, and the treatment of whitespace,
+     XML comments and processing instructions:
+
+  <screen><![CDATA[
+CREATE TABLE xmlelements AS SELECT
+xml $$
+  <root>
+   <element>  Hello<!-- xyxxz -->2a2<?aaaaa?> <!--x-->  bbb<x>xxx</x>CC  </element>
+  </root>
+$$ AS data;
+
+SELECT xmltable.*
+  FROM xmlelements, XMLTABLE('/root' PASSING data COLUMNS element text);
+         element
+-------------------------
+   Hello2a2   bbbxxxCC
+]]></screen>
+    </para>
+
+    <para>
+     The following example illustrates how
+     the <literal>XMLNAMESPACES</literal> clause can be used to specify
+     a list of namespaces
+     used in the XML document as well as in the XPath expressions:
+
+  <screen><![CDATA[
+WITH xmldata(data) AS (VALUES ('
+<example xmlns="http://example.com/myns" xmlns:B="http://example.com/b">
+ <item foo="1" B:bar="2"/>
+ <item foo="3" B:bar="4"/>
+ <item foo="4" B:bar="5"/>
+</example>'::xml)
+)
+SELECT xmltable.*
+  FROM XMLTABLE(XMLNAMESPACES('http://example.com/myns' AS x,
+                              'http://example.com/b' AS "B"),
+             '/x:example/x:item'
+                PASSING (SELECT data FROM xmldata)
+                COLUMNS foo int PATH '@foo',
+                  bar int PATH '@B:bar');
+ foo | bar
+-----+-----
+   1 |   2
+   3 |   4
+   4 |   5
+(3 rows)
+]]></screen>
+    </para>
+   </sect3>
+  </sect2>
+
+  <sect2 id="functions-xml-mapping">
+   <title>Mapping Tables to XML</title>
+
+   <indexterm zone="functions-xml-mapping">
+    <primary>XML export</primary>
+   </indexterm>
+
+   <para>
+    The following functions map the contents of relational tables to
+    XML values.  They can be thought of as XML export functionality:
+<synopsis>
+<function>table_to_xml</function> ( <parameter>table</parameter> <type>regclass</type>, <parameter>nulls</parameter> <type>boolean</type>,
+               <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
+<function>query_to_xml</function> ( <parameter>query</parameter> <type>text</type>, <parameter>nulls</parameter> <type>boolean</type>,
+               <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
+<function>cursor_to_xml</function> ( <parameter>cursor</parameter> <type>refcursor</type>, <parameter>count</parameter> <type>integer</type>, <parameter>nulls</parameter> <type>boolean</type>,
+                <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
+</synopsis>
+   </para>
+
+   <para>
+    <function>table_to_xml</function> maps the content of the named
+    table, passed as parameter <parameter>table</parameter>.  The
+    <type>regclass</type> type accepts strings identifying tables using the
+    usual notation, including optional schema qualification and
+    double quotes (see <xref linkend="datatype-oid"/> for details).
+    <function>query_to_xml</function> executes the
+    query whose text is passed as parameter
+    <parameter>query</parameter> and maps the result set.
+    <function>cursor_to_xml</function> fetches the indicated number of
+    rows from the cursor specified by the parameter
+    <parameter>cursor</parameter>.  This variant is recommended if
+    large tables have to be mapped, because the result value is built
+    up in memory by each function.
+   </para>
+
+   <para>
+    If <parameter>tableforest</parameter> is false, then the resulting
+    XML document looks like this:
+<screen><![CDATA[
+<tablename>
+  <row>
+    <columnname1>data</columnname1>
+    <columnname2>data</columnname2>
+  </row>
+
+  <row>
+    ...
+  </row>
+
+  ...
+</tablename>
+]]></screen>
+
+    If <parameter>tableforest</parameter> is true, the result is an
+    XML content fragment that looks like this:
+<screen><![CDATA[
+<tablename>
+  <columnname1>data</columnname1>
+  <columnname2>data</columnname2>
+</tablename>
+
+<tablename>
+  ...
+</tablename>
+
+...
+]]></screen>
+
+    If no table name is available, that is, when mapping a query or a
+    cursor, the string <literal>table</literal> is used in the first
+    format, <literal>row</literal> in the second format.
+   </para>
+
+   <para>
+    The choice between these formats is up to the user.  The first
+    format is a proper XML document, which will be important in many
+    applications.  The second format tends to be more useful in the
+    <function>cursor_to_xml</function> function if the result values are to be
+    reassembled into one document later on.  The functions for
+    producing XML content discussed above, in particular
+    <function>xmlelement</function>, can be used to alter the results
+    to taste.
+   </para>
+
+   <para>
+    The data values are mapped in the same way as described for the
+    function <function>xmlelement</function> above.
+   </para>
+
+   <para>
+    The parameter <parameter>nulls</parameter> determines whether null
+    values should be included in the output.  If true, null values in
+    columns are represented as:
+<screen><![CDATA[
+<columnname xsi:nil="true"/>
+]]></screen>
+    where <literal>xsi</literal> is the XML namespace prefix for XML
+    Schema Instance.  An appropriate namespace declaration will be
+    added to the result value.  If false, columns containing null
+    values are simply omitted from the output.
+   </para>
+
+   <para>
+    The parameter <parameter>targetns</parameter> specifies the
+    desired XML namespace of the result.  If no particular namespace
+    is wanted, an empty string should be passed.
+   </para>
+
+   <para>
+    The following functions return XML Schema documents describing the
+    mappings performed by the corresponding functions above:
+<synopsis>
+<function>table_to_xmlschema</function> ( <parameter>table</parameter> <type>regclass</type>, <parameter>nulls</parameter> <type>boolean</type>,
+                     <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
+<function>query_to_xmlschema</function> ( <parameter>query</parameter> <type>text</type>, <parameter>nulls</parameter> <type>boolean</type>,
+                     <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
+<function>cursor_to_xmlschema</function> ( <parameter>cursor</parameter> <type>refcursor</type>, <parameter>nulls</parameter> <type>boolean</type>,
+                      <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
+</synopsis>
+    It is essential that the same parameters are passed in order to
+    obtain matching XML data mappings and XML Schema documents.
+   </para>
+
+   <para>
+    The following functions produce XML data mappings and the
+    corresponding XML Schema in one document (or forest), linked
+    together.  They can be useful where self-contained and
+    self-describing results are wanted:
+<synopsis>
+<function>table_to_xml_and_xmlschema</function> ( <parameter>table</parameter> <type>regclass</type>, <parameter>nulls</parameter> <type>boolean</type>,
+                             <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
+<function>query_to_xml_and_xmlschema</function> ( <parameter>query</parameter> <type>text</type>, <parameter>nulls</parameter> <type>boolean</type>,
+                             <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
+</synopsis>
+   </para>
+
+   <para>
+    In addition, the following functions are available to produce
+    analogous mappings of entire schemas or the entire current
+    database:
+<synopsis>
+<function>schema_to_xml</function> ( <parameter>schema</parameter> <type>name</type>, <parameter>nulls</parameter> <type>boolean</type>,
+                <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
+<function>schema_to_xmlschema</function> ( <parameter>schema</parameter> <type>name</type>, <parameter>nulls</parameter> <type>boolean</type>,
+                      <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
+<function>schema_to_xml_and_xmlschema</function> ( <parameter>schema</parameter> <type>name</type>, <parameter>nulls</parameter> <type>boolean</type>,
+                              <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
+
+<function>database_to_xml</function> ( <parameter>nulls</parameter> <type>boolean</type>,
+                  <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
+<function>database_to_xmlschema</function> ( <parameter>nulls</parameter> <type>boolean</type>,
+                        <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
+<function>database_to_xml_and_xmlschema</function> ( <parameter>nulls</parameter> <type>boolean</type>,
+                                <parameter>tableforest</parameter> <type>boolean</type>, <parameter>targetns</parameter> <type>text</type> ) <returnvalue>xml</returnvalue>
+</synopsis>
+
+    These functions ignore tables that are not readable by the current user.
+    The database-wide functions additionally ignore schemas that the current
+    user does not have <literal>USAGE</literal> (lookup) privilege for.
+   </para>
+
+   <para>
+    Note that these potentially produce a lot of data, which needs to
+    be built up in memory.  When requesting content mappings of large
+    schemas or databases, it might be worthwhile to consider mapping the
+    tables separately instead, possibly even through a cursor.
+   </para>
+
+   <para>
+    The result of a schema content mapping looks like this:
+
+<screen><![CDATA[
+<schemaname>
+
+table1-mapping
+
+table2-mapping
+
+...
+
+</schemaname>]]></screen>
+
+    where the format of a table mapping depends on the
+    <parameter>tableforest</parameter> parameter as explained above.
+   </para>
+
+   <para>
+    The result of a database content mapping looks like this:
+
+<screen><![CDATA[
+<dbname>
+
+<schema1name>
+  ...
+</schema1name>
+
+<schema2name>
+  ...
+</schema2name>
+
+...
+
+</dbname>]]></screen>
+
+    where the schema mapping is as above.
+   </para>
+
+   <para>
+    As an example of using the output produced by these functions,
+    <xref linkend="xslt-xml-html"/> shows an XSLT stylesheet that
+    converts the output of
+    <function>table_to_xml_and_xmlschema</function> to an HTML
+    document containing a tabular rendition of the table data.  In a
+    similar manner, the results from these functions can be
+    converted into other XML-based formats.
+   </para>
+
+   <example id="xslt-xml-html">
+    <title>XSLT Stylesheet for Converting SQL/XML Output to HTML</title>
+<programlisting><![CDATA[
+<?xml version="1.0"?>
+<xsl:stylesheet version="1.0"
+    xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+    xmlns:xsd="http://www.w3.org/2001/XMLSchema"
+    xmlns="http://www.w3.org/1999/xhtml"
+>
+
+  <xsl:output method="xml"
+      doctype-system="http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"
+      doctype-public="-//W3C/DTD XHTML 1.0 Strict//EN"
+      indent="yes"/>
+
+  <xsl:template match="/*">
+    <xsl:variable name="schema" select="//xsd:schema"/>
+    <xsl:variable name="tabletypename"
+                  select="$schema/xsd:element[@name=name(current())]/@type"/>
+    <xsl:variable name="rowtypename"
+                  select="$schema/xsd:complexType[@name=$tabletypename]/xsd:sequence/xsd:element[@name='row']/@type"/>
+
+    <html>
+      <head>
+        <title><xsl:value-of select="name(current())"/></title>
+      </head>
+      <body>
+        <table>
+          <tr>
+            <xsl:for-each select="$schema/xsd:complexType[@name=$rowtypename]/xsd:sequence/xsd:element/@name">
+              <th><xsl:value-of select="."/></th>
+            </xsl:for-each>
+          </tr>
+
+          <xsl:for-each select="row">
+            <tr>
+              <xsl:for-each select="*">
+                <td><xsl:value-of select="."/></td>
+              </xsl:for-each>
+            </tr>
+          </xsl:for-each>
+        </table>
+      </body>
+    </html>
+  </xsl:template>
+
+</xsl:stylesheet>
+]]></programlisting>
+   </example>
+  </sect2>
+ </sect1>
diff --git a/doc/src/sgml/func/func.sgml b/doc/src/sgml/func/func.sgml
new file mode 100644
index 0000000000000..f351ef53f63d4
--- /dev/null
+++ b/doc/src/sgml/func/func.sgml
@@ -0,0 +1,84 @@
+<!-- doc/src/sgml/func.sgml -->
+
+ <chapter id="functions">
+  <title>Functions and Operators</title>
+
+  <indexterm zone="functions">
+   <primary>function</primary>
+  </indexterm>
+
+  <indexterm zone="functions">
+   <primary>operator</primary>
+  </indexterm>
+
+  <para>
+   <productname>PostgreSQL</productname> provides a large number of
+   functions and operators for the built-in data types.  This chapter
+   describes most of them, although additional special-purpose functions
+   appear in relevant sections of the manual.  Users can also
+   define their own functions and operators, as described in
+   <xref linkend="server-programming"/>.  The
+   <application>psql</application> commands <command>\df</command> and
+   <command>\do</command> can be used to list all
+   available functions and operators, respectively.
+  </para>
+
+  <para>
+   The notation used throughout this chapter to describe the argument and
+   result data types of a function or operator is like this:
+<synopsis>
+<function>repeat</function> ( <type>text</type>, <type>integer</type> ) <returnvalue>text</returnvalue>
+</synopsis>
+   which says that the function <function>repeat</function> takes one text and
+   one integer argument and returns a result of type text.  The right arrow
+   is also used to indicate the result of an example, thus:
+<programlisting>
+repeat('Pg', 4) <returnvalue>PgPgPgPg</returnvalue>
+</programlisting>
+  </para>
+
+  <para>
+   If you are concerned about portability then note that most of
+   the functions and operators described in this chapter, with the
+   exception of the most trivial arithmetic and comparison operators
+   and some explicitly marked functions, are not specified by the
+   <acronym>SQL</acronym> standard. Some of this extended functionality
+   is present in other <acronym>SQL</acronym> database management
+   systems, and in many cases this functionality is compatible and
+   consistent between the various implementations.
+  </para>
+
+
+&func-logical;
+&func-comparison;
+&func-math;
+&func-string;
+&func-binarystring;
+&func-bitstring;
+&func-matching;
+&func-formatting;
+&func-datetime;
+&func-enum;
+&func-geometry;
+&func-net;
+&func-textsearch;
+&func-uuid;
+&func-xml;
+&func-json;
+&func-sequence;
+&func-conditional;
+&func-array;
+&func-range;
+&func-aggregate;
+&func-window;
+&func-merge-support;
+&func-subquery;
+&func-comparisons;
+&func-srf;
+&func-info;
+&func-admin;
+&func-trigger;
+&func-event-triggers;
+&func-statistics;
+
+</chapter>
diff --git a/doc/src/sgml/gin.sgml b/doc/src/sgml/gin.sgml
index 46e87e01324dd..82410b1fbdfa1 100644
--- a/doc/src/sgml/gin.sgml
+++ b/doc/src/sgml/gin.sgml
@@ -394,7 +394,11 @@
                               Pointer extra_data)</function></term>
      <listitem>
       <para>
-       Compare a partial-match query key to an index key.  Returns an integer
+       Compare a partial-match query key to an index key.
+       <literal>partial_key</literal> is a query key that was returned
+       by <function>extractQuery</function> with an indication that it
+       requires partial match, and <literal>key</literal> is an index entry.
+       Returns an integer
        whose sign indicates the result: less than zero means the index key
        does not match the query, but the index scan should continue; zero
        means that the index key does match the query; greater than zero
diff --git a/doc/src/sgml/indexam.sgml b/doc/src/sgml/indexam.sgml
index 1aa4741a8eaee..63d7e376f195e 100644
--- a/doc/src/sgml/indexam.sgml
+++ b/doc/src/sgml/indexam.sgml
@@ -147,7 +147,7 @@ typedef struct IndexAmRoutine
     ambuild_function ambuild;
     ambuildempty_function ambuildempty;
     aminsert_function aminsert;
-    aminsertcleanup_function aminsertcleanup;
+    aminsertcleanup_function aminsertcleanup;   /* can be NULL */
     ambulkdelete_function ambulkdelete;
     amvacuumcleanup_function amvacuumcleanup;
     amcanreturn_function amcanreturn;   /* can be NULL */
diff --git a/doc/src/sgml/installation.sgml b/doc/src/sgml/installation.sgml
index de19f3ad92952..8e5da767c48b2 100644
--- a/doc/src/sgml/installation.sgml
+++ b/doc/src/sgml/installation.sgml
@@ -65,7 +65,7 @@
      </para>
 
      <para>
-      The minimum required version of <application>Meson</application> is 0.54.
+      The minimum required version of <application>Meson</application> is 0.57.2.
      </para>
     </listitem>
 
@@ -3847,17 +3847,13 @@ make: *** [postgres] Error 1
    <para>
     Both 32-bit and 64-bit builds are possible with the Microsoft Compiler suite.
     32-bit PostgreSQL builds are possible with
-    <productname>Visual Studio 2015</productname> to
+    <productname>Visual Studio 2019</productname> to
     <productname>Visual Studio 2022</productname>,
     as well as standalone Windows SDK releases 10 and above.
     64-bit PostgreSQL builds are supported with
     <productname>Microsoft Windows SDK</productname> version 10 and above or
-    <productname>Visual Studio 2015</productname> and above.
+    <productname>Visual Studio 2019</productname> and above.
     <!--
-        For 2015 requirements:
-        https://docs.microsoft.com/en-us/visualstudio/productinfo/vs2015-sysrequirements-vs
-        For 2017 requirements:
-        https://docs.microsoft.com/en-us/visualstudio/productinfo/vs2017-system-requirements-vs
         For 2019 requirements:
         https://docs.microsoft.com/en-us/visualstudio/releases/2019/system-requirements
         For 2022 requirements:
diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index 298c4b38ef90a..5bf59a1985559 100644
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -2320,6 +2320,19 @@ postgresql://%2Fvar%2Flib%2Fpostgresql/dbname
       </listitem>
      </varlistentry>
 
+     <varlistentry id="libpq-connect-servicefile" xreflabel="servicefile">
+      <term><literal>servicefile</literal></term>
+      <listitem>
+       <para>
+        This option specifies the name of the per-user connection service file
+        (see <xref linkend="libpq-pgservice"/>).
+        Defaults to <filename>~/.pg_service.conf</filename>, or
+        <filename>%APPDATA%\postgresql\.pg_service.conf</filename> on
+        Microsoft Windows.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="libpq-connect-target-session-attrs" xreflabel="target_session_attrs">
       <term><literal>target_session_attrs</literal></term>
       <listitem>
@@ -2740,26 +2753,6 @@ char *PQport(const PGconn *conn);
      </listitem>
     </varlistentry>
 
-    <varlistentry id="libpq-PQservice">
-     <term><function>PQservice</function><indexterm><primary>PQservice</primary></indexterm></term>
-
-     <listitem>
-      <para>
-       Returns the service of the active connection.
-
-<synopsis>
-char *PQservice(const PGconn *conn);
-</synopsis>
-      </para>
-
-      <para>
-       <xref linkend="libpq-PQservice"/> returns <symbol>NULL</symbol> if the
-       <parameter>conn</parameter> argument is <symbol>NULL</symbol>.
-       Otherwise, if there was no service provided, it returns an empty string.
-      </para>
-     </listitem>
-    </varlistentry>
-
     <varlistentry id="libpq-PQtty">
      <term><function>PQtty</function><indexterm><primary>PQtty</primary></indexterm></term>
 
@@ -9160,12 +9153,8 @@ myEventProc(PGEventId evtId, void *evtInfo, void *passThrough)
       <indexterm>
        <primary><envar>PGSERVICEFILE</envar></primary>
       </indexterm>
-      <envar>PGSERVICEFILE</envar> specifies the name of the per-user
-      connection service file
-      (see <xref linkend="libpq-pgservice"/>).
-      Defaults to <filename>~/.pg_service.conf</filename>, or
-      <filename>%APPDATA%\postgresql\.pg_service.conf</filename> on
-      Microsoft Windows.
+      <envar>PGSERVICEFILE</envar> behaves the same as the
+      <xref linkend="libpq-connect-servicefile"/> connection parameter.
      </para>
     </listitem>
 
@@ -9596,7 +9585,8 @@ myEventProc(PGEventId evtId, void *evtInfo, void *passThrough)
    On Microsoft Windows, it is named
    <filename>%APPDATA%\postgresql\.pg_service.conf</filename> (where
    <filename>%APPDATA%</filename> refers to the Application Data subdirectory
-   in the user's profile).  A different file name can be specified by
+   in the user's profile).  A different file name can be specified using the
+   <literal>servicefile</literal> key word in a libpq connection string or by
    setting the environment variable <envar>PGSERVICEFILE</envar>.
    The system-wide file is named <filename>pg_service.conf</filename>.
    By default it is sought in the <filename>etc</filename> directory
diff --git a/doc/src/sgml/logical-replication.sgml b/doc/src/sgml/logical-replication.sgml
index c32e6bc000d4d..a0761cfee3f6d 100644
--- a/doc/src/sgml/logical-replication.sgml
+++ b/doc/src/sgml/logical-replication.sgml
@@ -575,8 +575,8 @@ HINT:  To initiate replication, you must manually create the replication slot, e
 <programlisting>
 /* pub # */ SELECT * FROM pg_create_logical_replication_slot('sub1', 'pgoutput');
  slot_name |    lsn
------------+-----------
- sub1      | 0/19404D0
+-----------+------------
+ sub1      | 0/019404D0
 (1 row)
 </programlisting></para>
      </listitem>
@@ -617,8 +617,8 @@ HINT:  To initiate replication, you must manually create the replication slot, e
 <programlisting>
 /* pub # */ SELECT * FROM pg_create_logical_replication_slot('myslot', 'pgoutput');
  slot_name |    lsn
------------+-----------
- myslot    | 0/19059A0
+-----------+------------
+ myslot    | 0/019059A0
 (1 row)
 </programlisting></para>
      </listitem>
@@ -655,8 +655,8 @@ HINT:  To initiate replication, you must manually create the replication slot, e
 <programlisting>
 /* pub # */ SELECT * FROM pg_create_logical_replication_slot('myslot', 'pgoutput');
  slot_name |    lsn
------------+-----------
- myslot    | 0/1905930
+-----------+------------
+ myslot    | 0/01905930
 (1 row)
 </programlisting></para>
      </listitem>
@@ -709,8 +709,8 @@ HINT:  To initiate replication, you must manually create the replication slot, e
   </para>
 
   <para>
-   To confirm that the standby server is indeed ready for failover, follow these
-   steps to verify that all necessary logical replication slots have been
+   To confirm that the standby server is indeed ready for failover for a given subscriber, follow these
+   steps to verify that all the logical replication slots required by that subscriber have been
    synchronized to the standby server:
   </para>
 
@@ -764,7 +764,7 @@ HINT:  To initiate replication, you must manually create the replication slot, e
      Check that the logical replication slots identified above exist on
      the standby server and are ready for failover.
 <programlisting>
-/* standby # */ SELECT slot_name, (synced AND NOT temporary AND NOT conflicting) AS failover_ready
+/* standby # */ SELECT slot_name, (synced AND NOT temporary AND invalidation_reason IS NULL) AS failover_ready
                FROM pg_replication_slots
                WHERE slot_name IN
                    ('sub1','sub2','sub3', 'pg_16394_sync_16385_7394666715149055164');
@@ -782,10 +782,42 @@ HINT:  To initiate replication, you must manually create the replication slot, e
   <para>
    If all the slots are present on the standby server and the result
    (<literal>failover_ready</literal>) of the above SQL query is true, then
-   existing subscriptions can continue subscribing to publications now on the
-   new primary server.
+   existing subscriptions can continue subscribing to publications on the new
+   primary server.
   </para>
 
+  <para>
+   The first two steps in the above procedure are meant for a
+   <productname>PostgreSQL</productname> subscriber. It is recommended to run
+   these steps on each subscriber node, that will be served by the designated
+   standby after failover, to obtain the complete list of replication
+   slots. This list can then be verified in Step 3 to ensure failover readiness.
+   Non-<productname>PostgreSQL</productname> subscribers, on the other hand, may
+   use their own methods to identify the replication slots used by their
+   respective subscriptions.
+  </para>
+
+  <para>
+   In some cases, such as during a planned failover, it is necessary to confirm
+   that all subscribers, whether <productname>PostgreSQL</productname> or
+   non-<productname>PostgreSQL</productname>, will be able to continue
+   replication after failover to a given standby server. In such cases, use the
+   following SQL, instead of performing the first two steps above, to identify
+   which replication slots on the primary need to be synced to the standby that
+   is intended for promotion. This query returns the relevant replication slots
+   associated with all the failover-enabled subscriptions.
+  </para>
+
+   <para>
+<programlisting>
+/* primary # */ SELECT array_agg(quote_literal(r.slot_name)) AS slots
+               FROM pg_replication_slots r
+               WHERE r.failover AND NOT r.temporary;
+ slots
+-------
+ {'sub1','sub2','sub3', 'pg_16394_sync_16385_7394666715149055164'}
+(1 row)
+</programlisting></para>
  </sect1>
 
  <sect1 id="logical-replication-row-filter">
@@ -1016,28 +1048,28 @@ HINT:  To initiate replication, you must manually create the replication slot, e
     defined) for each publication.
 <programlisting><![CDATA[
 /* pub # */ \dRp+
-          Publication p1
-  Owner   | All tables | Inserts | Updates | Deletes | Truncates | Via root
-----------+------------+---------+---------+---------+-----------+----------
- postgres | f          | t       | t       | t       | t         | f
+                                         Publication p1
+  Owner   | All tables | Inserts | Updates | Deletes | Truncates | Generated columns | Via root
+----------+------------+---------+---------+---------+-----------+-------------------+----------
+ postgres | f          | t       | t       | t       | t         | none              | f
 Tables:
- "public.t1" WHERE ((a > 5) AND (c = 'NSW'::text))
+    "public.t1" WHERE ((a > 5) AND (c = 'NSW'::text))
 
-          Publication p2
-  Owner   | All tables | Inserts | Updates | Deletes | Truncates | Via root
-----------+------------+---------+---------+---------+-----------+----------
- postgres | f          | t       | t       | t       | t         | f
+                                         Publication p2
+  Owner   | All tables | Inserts | Updates | Deletes | Truncates | Generated columns | Via root
+----------+------------+---------+---------+---------+-----------+-------------------+----------
+ postgres | f          | t       | t       | t       | t         | none              | f
 Tables:
- "public.t1"
- "public.t2" WHERE (e = 99)
+    "public.t1"
+    "public.t2" WHERE (e = 99)
 
-          Publication p3
-  Owner   | All tables | Inserts | Updates | Deletes | Truncates | Via root
-----------+------------+---------+---------+---------+-----------+----------
- postgres | f          | t       | t       | t       | t         | f
+                                         Publication p3
+  Owner   | All tables | Inserts | Updates | Deletes | Truncates | Generated columns | Via root
+----------+------------+---------+---------+---------+-----------+-------------------+----------
+ postgres | f          | t       | t       | t       | t         | none              | f
 Tables:
- "public.t2" WHERE (d = 10)
- "public.t3" WHERE (g = 10)
+    "public.t2" WHERE (d = 10)
+    "public.t3" WHERE (g = 10)
 ]]></programlisting></para>
 
    <para>
@@ -1459,10 +1491,10 @@ Publications:
      for each publication.
 <programlisting>
 /* pub # */ \dRp+
-                               Publication p1
-  Owner   | All tables | Inserts | Updates | Deletes | Truncates | Via root
-----------+------------+---------+---------+---------+-----------+----------
- postgres | f          | t       | t       | t       | t         | f
+                                         Publication p1
+  Owner   | All tables | Inserts | Updates | Deletes | Truncates | Generated columns | Via root
+----------+------------+---------+---------+---------+-----------+-------------------+----------
+ postgres | f          | t       | t       | t       | t         | none              | f
 Tables:
     "public.t1" (id, a, b, d)
 </programlisting></para>
@@ -1772,6 +1804,22 @@ Publications:
       </para>
      </listitem>
     </varlistentry>
+    <varlistentry id="conflict-update-deleted" xreflabel="update_deleted">
+     <term><literal>update_deleted</literal></term>
+     <listitem>
+      <para>
+       The tuple to be updated was concurrently deleted by another origin. The
+       update will simply be skipped in this scenario. Note that this conflict
+       can only be detected when
+       <link linkend="guc-track-commit-timestamp"><varname>track_commit_timestamp</varname></link>
+       and <link linkend="sql-createsubscription-params-with-retain-dead-tuples"><literal>retain_dead_tuples</literal></link>
+       are enabled. Note that if a tuple cannot be found due to the table being
+       truncated, only a <literal>update_missing</literal> conflict will
+       arise. Additionally, if the tuple was deleted by the same origin, an
+       <literal>update_missing</literal> conflict will arise.
+      </para>
+     </listitem>
+    </varlistentry>
     <varlistentry id="conflict-update-missing" xreflabel="update_missing">
      <term><literal>update_missing</literal></term>
      <listitem>
@@ -1965,15 +2013,15 @@ DETAIL:  <replaceable class="parameter">detailed_explanation</replaceable>.
 ERROR:  conflict detected on relation "public.test": conflict=insert_exists
 DETAIL:  Key already exists in unique index "t_pkey", which was modified locally in transaction 740 at 2024-06-26 10:47:04.727375+08.
 Key (c)=(1); existing local tuple (1, 'local'); remote tuple (1, 'remote').
-CONTEXT:  processing remote data for replication origin "pg_16395" during "INSERT" for replication target relation "public.test" in transaction 725 finished at 0/14C0378
+CONTEXT:  processing remote data for replication origin "pg_16395" during "INSERT" for replication target relation "public.test" in transaction 725 finished at 0/014C0378
 </screen>
    The LSN of the transaction that contains the change violating the constraint and
-   the replication origin name can be found from the server log (LSN 0/14C0378 and
+   the replication origin name can be found from the server log (LSN 0/014C0378 and
    replication origin <literal>pg_16395</literal> in the above case).  The
    transaction that produced the conflict can be skipped by using
    <link linkend="sql-altersubscription-params-skip"><command>ALTER SUBSCRIPTION ... SKIP</command></link>
    with the finish LSN
-   (i.e., LSN 0/14C0378).  The finish LSN could be an LSN at which the transaction
+   (i.e., LSN 0/014C0378).  The finish LSN could be an LSN at which the transaction
    is committed or prepared on the publisher.  Alternatively, the transaction can
    also be skipped by calling the <link linkend="pg-replication-origin-advance">
    <function>pg_replication_origin_advance()</function></link> function.
@@ -1984,7 +2032,7 @@ CONTEXT:  processing remote data for replication origin "pg_16395" during "INSER
    <link linkend="sql-createsubscription-params-with-disable-on-error"><literal>disable_on_error</literal></link>
    option. Then, you can use <function>pg_replication_origin_advance()</function>
    function with the <parameter>node_name</parameter> (i.e., <literal>pg_16395</literal>)
-   and the next LSN of the finish LSN (i.e., 0/14C0379).  The current position of
+   and the next LSN of the finish LSN (i.e., 0/014C0379).  The current position of
    origins can be seen in the <link linkend="view-pg-replication-origin-status">
    <structname>pg_replication_origin_status</structname></link> system view.
    Please note that skipping the whole transaction includes skipping changes that
@@ -2364,6 +2412,12 @@ CONTEXT:  processing remote data for replication origin "pg_16395" during "INSER
     the subscriber, plus some reserve for table synchronization.
    </para>
 
+   <para>
+    <link linkend="guc-max-replication-slots"><varname>max_replication_slots</varname></link>
+    must be set to at least 1 when <link linkend="sql-createsubscription-params-with-retain-dead-tuples"><literal>retain_dead_tuples</literal></link>
+    is enabled for any subscription.
+   </para>
+
    <para>
     <link linkend="guc-max-logical-replication-workers"><varname>max_logical_replication_workers</varname></link>
     must be set to at least the number of subscriptions (for leader apply
@@ -2500,6 +2554,22 @@ CONTEXT:  processing remote data for replication origin "pg_16395" during "INSER
     dependencies on clusters before version 17.0 will silently be ignored.
    </para>
 
+   <note>
+    <para>
+     Commit timestamps and origin data are not preserved during the upgrade.
+     As a result, even if
+     <link linkend="sql-createsubscription-params-with-retain-dead-tuples"><literal>retain_dead_tuples</literal></link>
+     is enabled, the upgraded subscriber may be unable to detect conflicts or
+     log relevant commit timestamps and origins when applying changes from the
+     publisher occurred before the upgrade. Additionally, immediately after the
+     upgrade, the vacuum may remove the deleted rows that are required for
+     conflict detection. This can affect the changes that were not replicated
+     before the upgrade. To ensure consistent conflict tracking, users should
+     ensure that all potentially conflicting changes are replicated to the
+     subscriber before initiating the upgrade.
+    </para>
+   </note>
+
    <para>
     There are some prerequisites for <application>pg_upgrade</application> to
     be able to upgrade the subscriptions. If these are not met an error
@@ -2531,6 +2601,16 @@ CONTEXT:  processing remote data for replication origin "pg_16395" during "INSER
       subscriptions present in the old cluster.
      </para>
     </listitem>
+    <listitem>
+     <para>
+      If there are subscriptions with retain_dead_tuples enabled, the reserved
+      replication slot <quote><literal>pg_conflict_detection</literal></quote>
+      must not exist on the new cluster. Additionally, the
+      <link linkend="guc-wal-level"><varname>wal_level</varname></link> on the
+      new cluster must be set to <literal>replica</literal> or
+      <literal>logical</literal>.
+     </para>
+    </listitem>
    </itemizedlist>
   </sect2>
 
diff --git a/doc/src/sgml/logicaldecoding.sgml b/doc/src/sgml/logicaldecoding.sgml
index fc288d691b9f6..593f784b69dcb 100644
--- a/doc/src/sgml/logicaldecoding.sgml
+++ b/doc/src/sgml/logicaldecoding.sgml
@@ -57,14 +57,14 @@
 postgres=# -- Create a slot named 'regression_slot' using the output plugin 'test_decoding'
 postgres=# SELECT * FROM pg_create_logical_replication_slot('regression_slot', 'test_decoding', false, true);
     slot_name    |    lsn
------------------+-----------
- regression_slot | 0/16B1970
+-----------------+------------
+ regression_slot | 0/016B1970
 (1 row)
 
 postgres=# SELECT slot_name, plugin, slot_type, database, active, restart_lsn, confirmed_flush_lsn FROM pg_replication_slots;
     slot_name    |    plugin     | slot_type | database | active | restart_lsn | confirmed_flush_lsn
------------------+---------------+-----------+----------+--------+-------------+-----------------
- regression_slot | test_decoding | logical   | postgres | f      | 0/16A4408   | 0/16A4440
+-----------------+---------------+-----------+----------+--------+-------------+---------------------
+ regression_slot | test_decoding | logical   | postgres | f      | 0/016A4408  | 0/016A4440
 (1 row)
 
 postgres=# -- There are no changes to see yet
@@ -78,10 +78,10 @@ CREATE TABLE
 
 postgres=# -- DDL isn't replicated, so all you'll see is the transaction
 postgres=# SELECT * FROM pg_logical_slot_get_changes('regression_slot', NULL, NULL);
-    lsn    |  xid  |     data
------------+-------+--------------
- 0/BA2DA58 | 10297 | BEGIN 10297
- 0/BA5A5A0 | 10297 | COMMIT 10297
+    lsn     |  xid  |     data
+------------+-------+--------------
+ 0/0BA2DA58 | 10297 | BEGIN 10297
+ 0/0BA5A5A0 | 10297 | COMMIT 10297
 (2 rows)
 
 postgres=# -- Once changes are read, they're consumed and not emitted
@@ -97,41 +97,41 @@ postgres=*# INSERT INTO data(data) VALUES('2');
 postgres=*# COMMIT;
 
 postgres=# SELECT * FROM pg_logical_slot_get_changes('regression_slot', NULL, NULL);
-    lsn    |  xid  |                          data
------------+-------+---------------------------------------------------------
- 0/BA5A688 | 10298 | BEGIN 10298
- 0/BA5A6F0 | 10298 | table public.data: INSERT: id[integer]:1 data[text]:'1'
- 0/BA5A7F8 | 10298 | table public.data: INSERT: id[integer]:2 data[text]:'2'
- 0/BA5A8A8 | 10298 | COMMIT 10298
+    lsn     |  xid  |                          data
+------------+-------+---------------------------------------------------------
+ 0/0BA5A688 | 10298 | BEGIN 10298
+ 0/0BA5A6F0 | 10298 | table public.data: INSERT: id[integer]:1 data[text]:'1'
+ 0/0BA5A7F8 | 10298 | table public.data: INSERT: id[integer]:2 data[text]:'2'
+ 0/0BA5A8A8 | 10298 | COMMIT 10298
 (4 rows)
 
 postgres=# INSERT INTO data(data) VALUES('3');
 
 postgres=# -- You can also peek ahead in the change stream without consuming changes
 postgres=# SELECT * FROM pg_logical_slot_peek_changes('regression_slot', NULL, NULL);
-    lsn    |  xid  |                          data
------------+-------+---------------------------------------------------------
- 0/BA5A8E0 | 10299 | BEGIN 10299
- 0/BA5A8E0 | 10299 | table public.data: INSERT: id[integer]:3 data[text]:'3'
- 0/BA5A990 | 10299 | COMMIT 10299
+    lsn     |  xid  |                          data
+------------+-------+---------------------------------------------------------
+ 0/0BA5A8E0 | 10299 | BEGIN 10299
+ 0/0BA5A8E0 | 10299 | table public.data: INSERT: id[integer]:3 data[text]:'3'
+ 0/0BA5A990 | 10299 | COMMIT 10299
 (3 rows)
 
 postgres=# -- The next call to pg_logical_slot_peek_changes() returns the same changes again
 postgres=# SELECT * FROM pg_logical_slot_peek_changes('regression_slot', NULL, NULL);
-    lsn    |  xid  |                          data
------------+-------+---------------------------------------------------------
- 0/BA5A8E0 | 10299 | BEGIN 10299
- 0/BA5A8E0 | 10299 | table public.data: INSERT: id[integer]:3 data[text]:'3'
- 0/BA5A990 | 10299 | COMMIT 10299
+    lsn     |  xid  |                          data
+------------+-------+---------------------------------------------------------
+ 0/0BA5A8E0 | 10299 | BEGIN 10299
+ 0/0BA5A8E0 | 10299 | table public.data: INSERT: id[integer]:3 data[text]:'3'
+ 0/0BA5A990 | 10299 | COMMIT 10299
 (3 rows)
 
 postgres=# -- options can be passed to output plugin, to influence the formatting
 postgres=# SELECT * FROM pg_logical_slot_peek_changes('regression_slot', NULL, NULL, 'include-timestamp', 'on');
-    lsn    |  xid  |                          data
------------+-------+---------------------------------------------------------
- 0/BA5A8E0 | 10299 | BEGIN 10299
- 0/BA5A8E0 | 10299 | table public.data: INSERT: id[integer]:3 data[text]:'3'
- 0/BA5A990 | 10299 | COMMIT 10299 (at 2017-05-10 12:07:21.272494-04)
+    lsn     |  xid  |                          data
+------------+-------+---------------------------------------------------------
+ 0/0BA5A8E0 | 10299 | BEGIN 10299
+ 0/0BA5A8E0 | 10299 | table public.data: INSERT: id[integer]:3 data[text]:'3'
+ 0/0BA5A990 | 10299 | COMMIT 10299 (at 2017-05-10 12:07:21.272494-04)
 (3 rows)
 
 postgres=# -- Remember to destroy a slot you no longer need to stop it consuming
@@ -200,18 +200,18 @@ postgres=*# INSERT INTO data(data) VALUES('5');
 postgres=*# PREPARE TRANSACTION 'test_prepared1';
 
 postgres=# SELECT * FROM pg_logical_slot_get_changes('regression_slot', NULL, NULL);
-    lsn    | xid |                          data
------------+-----+---------------------------------------------------------
- 0/1689DC0 | 529 | BEGIN 529
- 0/1689DC0 | 529 | table public.data: INSERT: id[integer]:3 data[text]:'5'
- 0/1689FC0 | 529 | PREPARE TRANSACTION 'test_prepared1', txid 529
+    lsn     | xid |                          data
+------------+-----+---------------------------------------------------------
+ 0/01689DC0 | 529 | BEGIN 529
+ 0/01689DC0 | 529 | table public.data: INSERT: id[integer]:3 data[text]:'5'
+ 0/01689FC0 | 529 | PREPARE TRANSACTION 'test_prepared1', txid 529
 (3 rows)
 
 postgres=# COMMIT PREPARED 'test_prepared1';
 postgres=# select * from pg_logical_slot_get_changes('regression_slot', NULL, NULL);
-    lsn    | xid |                    data
------------+-----+--------------------------------------------
- 0/168A060 | 529 | COMMIT PREPARED 'test_prepared1', txid 529
+    lsn     | xid |                    data
+------------+-----+--------------------------------------------
+ 0/0168A060 | 529 | COMMIT PREPARED 'test_prepared1', txid 529
 (4 row)
 
 postgres=#-- you can also rollback a prepared transaction
@@ -219,18 +219,18 @@ postgres=# BEGIN;
 postgres=*# INSERT INTO data(data) VALUES('6');
 postgres=*# PREPARE TRANSACTION 'test_prepared2';
 postgres=# select * from pg_logical_slot_get_changes('regression_slot', NULL, NULL);
-    lsn    | xid |                          data
------------+-----+---------------------------------------------------------
- 0/168A180 | 530 | BEGIN 530
- 0/168A1E8 | 530 | table public.data: INSERT: id[integer]:4 data[text]:'6'
- 0/168A430 | 530 | PREPARE TRANSACTION 'test_prepared2', txid 530
+    lsn     | xid |                          data
+------------+-----+---------------------------------------------------------
+ 0/0168A180 | 530 | BEGIN 530
+ 0/0168A1E8 | 530 | table public.data: INSERT: id[integer]:4 data[text]:'6'
+ 0/0168A430 | 530 | PREPARE TRANSACTION 'test_prepared2', txid 530
 (3 rows)
 
 postgres=# ROLLBACK PREPARED 'test_prepared2';
 postgres=# select * from pg_logical_slot_get_changes('regression_slot', NULL, NULL);
-    lsn    | xid |                     data
------------+-----+----------------------------------------------
- 0/168A4B8 | 530 | ROLLBACK PREPARED 'test_prepared2', txid 530
+    lsn     | xid |                     data
+------------+-----+----------------------------------------------
+ 0/0168A4B8 | 530 | ROLLBACK PREPARED 'test_prepared2', txid 530
 (1 row)
 </programlisting>
 </sect1>
@@ -431,7 +431,7 @@ postgres=# select * from pg_logical_slot_get_changes('regression_slot', NULL, NU
      cases, the following log message may appear:
 <programlisting>
      LOG:  could not synchronize replication slot "failover_slot"
-     DETAIL:  Synchronization could lead to data loss as the remote slot needs WAL at LSN 0/3003F28 and catalog xmin 754, but the standby has LSN 0/3003F28 and catalog xmin 756
+     DETAIL:  Synchronization could lead to data loss as the remote slot needs WAL at LSN 0/03003F28 and catalog xmin 754, but the standby has LSN 0/03003F28 and catalog xmin 756
 </programlisting>
      If the logical replication slot is actively used by a consumer, no
      manual intervention is needed; the slot will advance automatically,
@@ -1412,7 +1412,7 @@ commit_prepared_cb(...);  &lt;-- commit of the prepared transaction
     currently used for decoded changes) is selected and streamed.  However, in
     some cases we still have to spill to disk even if streaming is enabled
     because we exceed the memory threshold but still have not decoded the
-    complete tuple e.g., only decoded toast table insert but not the main table
+    complete tuple e.g., only decoded TOAST table insert but not the main table
     insert.
    </para>
 
diff --git a/doc/src/sgml/maintenance.sgml b/doc/src/sgml/maintenance.sgml
index 600e4b3f2f3b8..e7a9f58c01582 100644
--- a/doc/src/sgml/maintenance.sgml
+++ b/doc/src/sgml/maintenance.sgml
@@ -779,7 +779,10 @@ HINT:  Execute a database-wide VACUUM in that database.
      careful aging management, storage cleanup, and wraparound handling.
      There is a separate storage area which holds the list of members in
      each multixact, which also uses a 32-bit counter and which must also
-     be managed.
+     be managed.  The system function
+     <function>pg_get_multixact_members()</function> described in
+     <xref linkend="functions-pg-snapshot"/> can be used to examine the
+     transaction IDs associated with a multixact ID.
     </para>
 
     <para>
diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 4265a22d4de35..3f4a27a736e27 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -2223,6 +2223,17 @@ description | Waiting for a newly initialized WAL file to reach durable storage
       </para></entry>
      </row>
 
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>confl_update_deleted</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times the tuple to be updated was concurrently deleted by
+       another source during the application of changes. See <xref linkend="conflict-update-deleted"/>
+       for details about this conflict.
+      </para></entry>
+     </row>
+
      <row>
       <entry role="catalog_table_entry"><para role="column_definition">
        <structfield>confl_update_missing</structfield> <type>bigint</type>
@@ -3980,6 +3991,7 @@ description | Waiting for a newly initialized WAL file to reach durable storage
       </para>
       <para>
        Estimated number of rows inserted since this table was last vacuumed
+       (not counting <command>VACUUM FULL</command>)
       </para></entry>
      </row>
 
@@ -4066,7 +4078,8 @@ description | Waiting for a newly initialized WAL file to reach durable storage
        <structfield>total_vacuum_time</structfield> <type>double precision</type>
       </para>
       <para>
-       Total time this table has been manually vacuumed, in milliseconds.
+       Total time this table has been manually vacuumed, in milliseconds
+       (not counting <command>VACUUM FULL</command>).
        (This includes the time spent sleeping due to cost-based delays.)
       </para></entry>
      </row>
@@ -6778,6 +6791,16 @@ FROM pg_stat_get_backend_idset() AS backendid;
        advances when the phase is <literal>streaming database files</literal>.
       </para></entry>
      </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>backup_type</structfield> <type>text</type>
+      </para>
+      <para>
+        Backup type. Either <literal>full</literal> or
+        <literal>incremental</literal>.
+      </para></entry>
+     </row>
     </tbody>
    </tgroup>
   </table>
diff --git a/doc/src/sgml/pageinspect.sgml b/doc/src/sgml/pageinspect.sgml
index 487c5d758ffbf..f5014787c783b 100644
--- a/doc/src/sgml/pageinspect.sgml
+++ b/doc/src/sgml/pageinspect.sgml
@@ -73,9 +73,9 @@
       passed as argument.  For example:
 <screen>
 test=# SELECT * FROM page_header(get_raw_page('pg_class', 0));
-    lsn    | checksum | flags  | lower | upper | special | pagesize | version | prune_xid
------------+----------+--------+-------+-------+---------+----------+---------+-----------
- 0/24A1B50 |        0 |      1 |   232 |   368 |    8192 |     8192 |       4 |         0
+    lsn     | checksum | flags  | lower | upper | special | pagesize | version | prune_xid
+------------+----------+--------+-------+-------+---------+----------+---------+-----------
+ 0/024A1B50 |        0 |      1 |   232 |   368 |    8192 |     8192 |       4 |         0
 </screen>
       The returned columns correspond to the fields in the
       <structname>PageHeaderData</structname> struct.
@@ -741,9 +741,9 @@ test=# SELECT first_tid, nbytes, tids[0:5] AS some_tids
       For example:
 <screen>
 test=# SELECT * FROM gist_page_opaque_info(get_raw_page('test_gist_idx', 2));
- lsn | nsn | rightlink | flags
------+-----+-----------+--------
- 0/1 | 0/0 |         1 | {leaf}
+    lsn     |    nsn     | rightlink | flags
+------------+------------+-----------+--------
+ 0/0B5FE088 | 0/00000000 |         1 | {leaf}
 (1 row)
 </screen>
      </para>
diff --git a/doc/src/sgml/pgbuffercache.sgml b/doc/src/sgml/pgbuffercache.sgml
index 537d601494242..eeb85a0e04908 100644
--- a/doc/src/sgml/pgbuffercache.sgml
+++ b/doc/src/sgml/pgbuffercache.sgml
@@ -19,10 +19,18 @@
   <primary>pg_buffercache_pages</primary>
  </indexterm>
 
+ <indexterm>
+  <primary>pg_buffercache_numa</primary>
+ </indexterm>
+
  <indexterm>
   <primary>pg_buffercache_summary</primary>
  </indexterm>
 
+ <indexterm>
+  <primary>pg_buffercache_usage_counts</primary>
+ </indexterm>
+
  <indexterm>
   <primary>pg_buffercache_evict</primary>
  </indexterm>
@@ -37,12 +45,12 @@
 
  <para>
   This module provides the <function>pg_buffercache_pages()</function>
-  function (wrapped in the <structname>pg_buffercache</structname> view),
+  function (wrapped in the <structname>pg_buffercache</structname> view), the
   <function>pg_buffercache_numa_pages()</function> function (wrapped in the
   <structname>pg_buffercache_numa</structname> view), the
   <function>pg_buffercache_summary()</function> function, the
   <function>pg_buffercache_usage_counts()</function> function, the
-  <function>pg_buffercache_evict()</function>, the
+  <function>pg_buffercache_evict()</function> function, the
   <function>pg_buffercache_evict_relation()</function> function and the
   <function>pg_buffercache_evict_all()</function> function.
  </para>
@@ -55,7 +63,7 @@
  </para>
 
  <para>
-  The <function>pg_buffercache_numa_pages()</function> provides
+  The <function>pg_buffercache_numa_pages()</function> function provides
   <acronym>NUMA</acronym> node mappings for shared buffer entries. This
   information is not part of <function>pg_buffercache_pages()</function>
   itself, as it is much slower to retrieve.
@@ -489,7 +497,7 @@
  </sect2>
 
  <sect2 id="pgbuffercache-pg-buffercache-evict-relation">
-  <title>The <structname>pg_buffercache_evict_relation</structname> Function</title>
+  <title>The <structname>pg_buffercache_evict_relation()</structname> Function</title>
   <para>
    The <function>pg_buffercache_evict_relation()</function> function is very
    similar to the <function>pg_buffercache_evict()</function> function.  The
@@ -507,7 +515,7 @@
  </sect2>
 
  <sect2 id="pgbuffercache-pg-buffercache-evict-all">
-  <title>The <structname>pg_buffercache_evict_all</structname> Function</title>
+  <title>The <structname>pg_buffercache_evict_all()</structname> Function</title>
   <para>
    The <function>pg_buffercache_evict_all()</function> function is very
    similar to the <function>pg_buffercache_evict()</function> function.  The
diff --git a/doc/src/sgml/pglogicalinspect.sgml b/doc/src/sgml/pglogicalinspect.sgml
index 4b111f961133b..1c1a9d14e510a 100644
--- a/doc/src/sgml/pglogicalinspect.sgml
+++ b/doc/src/sgml/pglogicalinspect.sgml
@@ -95,7 +95,7 @@ two_phase_at             | 0/40796AF8
 initial_xmin_horizon     | 0
 building_full_snapshot   | f
 in_slot_creation         | f
-last_serialized_snapshot | 0/0
+last_serialized_snapshot | 0/00000000
 next_phase_at            | 0
 committed_count          | 0
 committed_xip            |
@@ -114,7 +114,7 @@ two_phase_at             | 0/40796AF8
 initial_xmin_horizon     | 0
 building_full_snapshot   | f
 in_slot_creation         | f
-last_serialized_snapshot | 0/0
+last_serialized_snapshot | 0/00000000
 next_phase_at            | 0
 committed_count          | 0
 committed_xip            |
diff --git a/doc/src/sgml/pgoverexplain.sgml b/doc/src/sgml/pgoverexplain.sgml
index 21930fbd3bd76..377ddc8139ecf 100644
--- a/doc/src/sgml/pgoverexplain.sgml
+++ b/doc/src/sgml/pgoverexplain.sgml
@@ -8,7 +8,7 @@
  </indexterm>
 
  <para>
-  The <filename>pg_overexplain</filename> extends <command>EXPLAIN</command>
+  The <filename>pg_overexplain</filename> module extends <command>EXPLAIN</command>
   with new options that provide additional output. It is mostly intended to
   assist with debugging of and development of the planner, rather than for
   general use. Since this module displays internal details of planner data
@@ -17,6 +17,21 @@
   often as) those data structures change.
  </para>
 
+ <para>
+  To use it, simply load it into the server.  You can load it into an
+  individual session:
+
+<programlisting>
+LOAD 'pg_overexplain';
+</programlisting>
+
+  You can also preload it into some or all sessions by including
+  <literal>pg_overexplain</literal> in
+  <xref linkend="guc-session-preload-libraries"/> or
+  <xref linkend="guc-shared-preload-libraries"/> in
+  <filename>postgresql.conf</filename>.
+ </para>
+
  <sect2 id="pgoverexplain-debug">
   <title>EXPLAIN (DEBUG)</title>
 
diff --git a/doc/src/sgml/pgstatstatements.sgml b/doc/src/sgml/pgstatstatements.sgml
index 7baa07dcdbf7f..d753de5836efb 100644
--- a/doc/src/sgml/pgstatstatements.sgml
+++ b/doc/src/sgml/pgstatstatements.sgml
@@ -554,6 +554,24 @@
       </para></entry>
      </row>
 
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>generic_plan_calls</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times the statement has been executed using a generic plan
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>custom_plan_calls</structfield> <type>bigint</type>
+      </para>
+      <para>
+       Number of times the statement has been executed using a custom plan
+      </para></entry>
+     </row>
+
      <row>
       <entry role="catalog_table_entry"><para role="column_definition">
        <structfield>stats_since</structfield> <type>timestamp with time zone</type>
diff --git a/doc/src/sgml/pgstattuple.sgml b/doc/src/sgml/pgstattuple.sgml
index 4071da4ed941a..c747a5818ab7d 100644
--- a/doc/src/sgml/pgstattuple.sgml
+++ b/doc/src/sgml/pgstattuple.sgml
@@ -270,6 +270,15 @@ leaf_fragmentation | 0
      page than is accounted for by <literal>internal_pages + leaf_pages +
      empty_pages + deleted_pages</literal>, because it also includes the
      index's metapage.
+     <literal>avg_leaf_density</literal> is the fraction of the index size that
+     is taken up by user data.  Since indexes have a default fillfactor of 90,
+     this should be around 90 for newly built indexes of non-negligible size,
+     but usually deteriorates over time.
+     <literal>leaf_fragmentation</literal> represents a measure of disorder.
+     A higher <literal>leaf_fragmentation</literal> indicates that the
+     physical order of the index leaf pages increasingly deviates from their
+     logical order. This can have a significant impact if a large part
+     of the index is read from disk.
     </para>
 
     <para>
diff --git a/doc/src/sgml/pgwalinspect.sgml b/doc/src/sgml/pgwalinspect.sgml
index 3a8121c70f1f1..79c3ead40bc71 100644
--- a/doc/src/sgml/pgwalinspect.sgml
+++ b/doc/src/sgml/pgwalinspect.sgml
@@ -73,9 +73,9 @@
 <screen>
 postgres=# SELECT * FROM pg_get_wal_record_info('0/E419E28');
 -[ RECORD 1 ]----+-------------------------------------------------
-start_lsn        | 0/E419E28
-end_lsn          | 0/E419E68
-prev_lsn         | 0/E419D78
+start_lsn        | 0/0E419E28
+end_lsn          | 0/0E419E68
+prev_lsn         | 0/0E419D78
 xid              | 0
 resource_manager | Heap2
 record_type      | VACUUM
@@ -146,9 +146,9 @@ block_ref        |
 <screen>
 postgres=# SELECT * FROM pg_get_wal_block_info('0/1230278', '0/12302B8');
 -[ RECORD 1 ]-----+-----------------------------------
-start_lsn         | 0/1230278
-end_lsn           | 0/12302B8
-prev_lsn          | 0/122FD40
+start_lsn         | 0/01230278
+end_lsn           | 0/012302B8
+prev_lsn          | 0/0122FD40
 block_id          | 0
 reltablespace     | 1663
 reldatabase       | 1
diff --git a/doc/src/sgml/protocol.sgml b/doc/src/sgml/protocol.sgml
index 82fe3f93761dc..cc5c8dc574ce5 100644
--- a/doc/src/sgml/protocol.sgml
+++ b/doc/src/sgml/protocol.sgml
@@ -537,6 +537,11 @@
         The frontend should not respond to this message, but should
         continue listening for a ReadyForQuery message.
        </para>
+       <para>
+        The <productname>PostgreSQL</productname> server will always send this
+        message, but some third party backend implementations of the protocol
+        that don't support query cancellation are known not to.
+       </para>
       </listitem>
      </varlistentry>
 
@@ -886,6 +891,16 @@ SELCT 1/0;<!-- this typo is intentional -->
      Errors detected at semantic analysis or later, such as a misspelled
      table or column name, do not have this effect.
     </para>
+
+    <para>
+     Lastly, note that all the statements within the Query message will
+     observe the same value of <function>statement_timestamp()</function>,
+     since that timestamp is updated only upon receipt of the Query
+     message.  This will result in them all observing the same
+     value of <function>transaction_timestamp()</function> as well,
+     except in cases where the query string ends a previously-started
+     transaction and begins a new one.
+    </para>
    </sect3>
   </sect2>
 
@@ -2225,6 +2240,8 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;"
          <para>
           The name of the slot to create. Must be a valid replication slot
           name (see <xref linkend="streaming-replication-slots-manipulation"/>).
+          The name cannot be <literal>pg_conflict_detection</literal> as it
+          is reserved for the conflict detection.
          </para>
         </listitem>
        </varlistentry>
@@ -2538,8 +2555,8 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;"
       </para>
 
       <variablelist>
-       <varlistentry id="protocol-replication-xlogdata">
-        <term>XLogData (B)</term>
+       <varlistentry id="protocol-replication-waldata">
+        <term>WALData (B)</term>
         <listitem>
          <variablelist>
           <varlistentry>
@@ -2587,11 +2604,11 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;"
             </para>
 
             <para>
-             A single WAL record is never split across two XLogData messages.
+             A single WAL record is never split across two WALData messages.
              When a WAL record crosses a WAL page boundary, and is therefore
              already split using continuation records, it can be split at the page
              boundary. In other words, the first main WAL record and its
-             continuation records can be sent in different XLogData messages.
+             continuation records can be sent in different WALData messages.
             </para>
            </listitem>
           </varlistentry>
@@ -2643,6 +2660,65 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;"
          </variablelist>
         </listitem>
        </varlistentry>
+
+       <varlistentry id="protocol-replication-primary-status-update">
+        <term>Primary status update (B)</term>
+        <listitem>
+         <variablelist>
+          <varlistentry>
+           <term>Byte1('s')</term>
+           <listitem>
+            <para>
+             Identifies the message as a primary status update.
+            </para>
+           </listitem>
+          </varlistentry>
+
+          <varlistentry>
+           <term>Int64</term>
+           <listitem>
+            <para>
+             The latest WAL write position on the server.
+            </para>
+           </listitem>
+          </varlistentry>
+
+          <varlistentry>
+           <term>Int64</term>
+           <listitem>
+            <para>
+             The oldest transaction ID that is currently in the commit phase on
+             the server, along with its epoch. The most significant 32 bits are
+             the epoch. The least significant 32 bits are the transaction ID.
+             If no transactions are active on the server, this number will be
+             the next transaction ID to be assigned.
+            </para>
+           </listitem>
+          </varlistentry>
+
+          <varlistentry>
+           <term>Int64</term>
+           <listitem>
+            <para>
+             The next transaction ID to be assigned on the server, along with
+             its epoch. The most significant 32 bits are the epoch. The least
+             significant 32 bits are the transaction ID.
+            </para>
+           </listitem>
+          </varlistentry>
+
+          <varlistentry>
+           <term>Int64</term>
+           <listitem>
+            <para>
+             The server's system clock at the time of transmission, as
+             microseconds since midnight on 2000-01-01.
+            </para>
+           </listitem>
+          </varlistentry>
+         </variablelist>
+        </listitem>
+       </varlistentry>
       </variablelist>
 
       <para>
@@ -2787,6 +2863,33 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;"
          </variablelist>
         </listitem>
        </varlistentry>
+
+       <varlistentry id="protocol-replication-standby-wal-status-request">
+        <term>Request primary status update (F)</term>
+        <listitem>
+         <variablelist>
+          <varlistentry>
+           <term>Byte1('p')</term>
+           <listitem>
+            <para>
+             Identifies the message as a request for a primary status update.
+            </para>
+           </listitem>
+          </varlistentry>
+
+          <varlistentry>
+           <term>Int64</term>
+           <listitem>
+            <para>
+             The client's system clock at the time of transmission, as
+             microseconds since midnight on 2000-01-01.
+            </para>
+           </listitem>
+          </varlistentry>
+         </variablelist>
+        </listitem>
+       </varlistentry>
+
       </variablelist>
      </listitem>
     </varlistentry>
@@ -3482,6 +3585,7 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;"
       <para>
        Boolean option to use binary transfer mode.  Binary mode is faster
        than the text mode but slightly less robust.
+       The default is <literal>off</literal>.
       </para>
      </listitem>
     </varlistentry>
@@ -3494,6 +3598,7 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;"
       <para>
        Boolean option to enable sending the messages that are written
        by <function>pg_logical_emit_message</function>.
+       The default is <literal>off</literal>.
       </para>
      </listitem>
     </varlistentry>
@@ -3504,11 +3609,13 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;"
      </term>
      <listitem>
       <para>
-       Boolean option to enable streaming of in-progress transactions.
-       It accepts an additional value "parallel" to enable sending extra
-       information with some messages to be used for parallelisation.
-       Minimum protocol version 2 is required to turn it on.  Minimum protocol
-       version 4 is required for the "parallel" option.
+       Option to enable streaming of in-progress transactions. Valid values are
+       <literal>off</literal> (the default), <literal>on</literal> and
+       <literal>parallel</literal>. The setting <literal>parallel</literal>
+       enables sending extra information with some messages to be used for
+       parallelization. Minimum protocol version 2 is required to turn it
+       <literal>on</literal>.  Minimum protocol version 4 is required for the
+       <literal>parallel</literal> value.
       </para>
      </listitem>
     </varlistentry>
@@ -3521,6 +3628,7 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;"
       <para>
        Boolean option to enable two-phase transactions.   Minimum protocol
        version 3 is required to turn it on.
+       The default is <literal>off</literal>.
       </para>
      </listitem>
     </varlistentry>
@@ -3537,6 +3645,7 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;"
        to send the changes regardless of their origin.  This can be used
        to avoid loops (infinite replication of the same data) among
        replication nodes.
+       The default is <literal>any</literal>.
       </para>
      </listitem>
     </varlistentry>
@@ -6081,13 +6190,14 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;"
       </varlistentry>
 
       <varlistentry>
-       <term>Int32(196608)</term>
+       <term>Int32</term>
        <listitem>
         <para>
          The protocol version number.  The most significant 16 bits are
-         the major version number (3 for the protocol described here).
-         The least significant 16 bits are the minor version number
-         (0 for the protocol described here).
+         the major version number. The least significant 16 bits are the minor
+         version number. As an example protocol version 3.2 is represented as
+         <literal>196610</literal> in decimal or more clearly as
+         <literal>0x00030002</literal> in hexadecimal.
         </para>
        </listitem>
       </varlistentry>
diff --git a/doc/src/sgml/query.sgml b/doc/src/sgml/query.sgml
index 727a0cb185fb2..b190f28d41ea6 100644
--- a/doc/src/sgml/query.sgml
+++ b/doc/src/sgml/query.sgml
@@ -264,8 +264,18 @@ COPY weather FROM '/home/user/weather.txt';
 
     where the file name for the source file must be available on the
     machine running the backend process, not the client, since the backend process
-    reads the file directly.  You can read more about the
-    <command>COPY</command> command in <xref linkend="sql-copy"/>.
+    reads the file directly.  The data inserted above into the weather table
+    could also be inserted from a file containing (values are separated by a
+    tab character):
+
+<programlisting>
+San Francisco    46    50    0.25    1994-11-27
+San Francisco    43    57    0.0    1994-11-29
+Hayward    37    54    \N    1994-11-29
+</programlisting>
+
+    You can read more about the <command>COPY</command> command in
+    <xref linkend="sql-copy"/>.
    </para>
   </sect1>
 
diff --git a/doc/src/sgml/ref/alter_subscription.sgml b/doc/src/sgml/ref/alter_subscription.sgml
index fdc648d007f1c..d48cdc76bd34d 100644
--- a/doc/src/sgml/ref/alter_subscription.sgml
+++ b/doc/src/sgml/ref/alter_subscription.sgml
@@ -235,8 +235,9 @@ ALTER SUBSCRIPTION <replaceable class="parameter">name</replaceable> RENAME TO <
       <link linkend="sql-createsubscription-params-with-password-required"><literal>password_required</literal></link>,
       <link linkend="sql-createsubscription-params-with-run-as-owner"><literal>run_as_owner</literal></link>,
       <link linkend="sql-createsubscription-params-with-origin"><literal>origin</literal></link>,
-      <link linkend="sql-createsubscription-params-with-failover"><literal>failover</literal></link>, and
-      <link linkend="sql-createsubscription-params-with-two-phase"><literal>two_phase</literal></link>.
+      <link linkend="sql-createsubscription-params-with-failover"><literal>failover</literal></link>,
+      <link linkend="sql-createsubscription-params-with-two-phase"><literal>two_phase</literal></link>, and
+      <link linkend="sql-createsubscription-params-with-retain-dead-tuples"><literal>retain_dead_tuples</literal></link>.
       Only a superuser can set <literal>password_required = false</literal>.
      </para>
 
@@ -261,8 +262,9 @@ ALTER SUBSCRIPTION <replaceable class="parameter">name</replaceable> RENAME TO <
      </para>
 
      <para>
-      The <link linkend="sql-createsubscription-params-with-failover"><literal>failover</literal></link>
-      and <link linkend="sql-createsubscription-params-with-two-phase"><literal>two_phase</literal></link>
+      The <link linkend="sql-createsubscription-params-with-failover"><literal>failover</literal></link>,
+      <link linkend="sql-createsubscription-params-with-two-phase"><literal>two_phase</literal></link>, and
+      <link linkend="sql-createsubscription-params-with-retain-dead-tuples"><literal>retain_dead_tuples</literal></link>
       parameters can only be altered when the subscription is disabled.
      </para>
 
@@ -285,6 +287,14 @@ ALTER SUBSCRIPTION <replaceable class="parameter">name</replaceable> RENAME TO <
       option is changed from <literal>true</literal> to <literal>false</literal>,
       the publisher will replicate the transactions again when they are committed.
      </para>
+
+     <para>
+      If the <link linkend="sql-createsubscription-params-with-retain-dead-tuples"><literal>retain_dead_tuples</literal></link>
+      option is altered to <literal>false</literal> and no other subscription
+      has this option enabled, the replication slot named
+      <quote><literal>pg_conflict_detection</literal></quote>, created to retain
+      dead tuples for conflict detection, will be dropped.
+     </para>
     </listitem>
    </varlistentry>
 
diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml
index d16969916835d..541e093a519d7 100644
--- a/doc/src/sgml/ref/alter_table.sgml
+++ b/doc/src/sgml/ref/alter_table.sgml
@@ -240,9 +240,10 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
       provided none of the records in the table contain a
       <literal>NULL</literal> value for the column.  Ordinarily this is
       checked during the <literal>ALTER TABLE</literal> by scanning the
-      entire table; however, if a valid <literal>CHECK</literal> constraint is
-      found which proves no <literal>NULL</literal> can exist, then the
-      table scan is skipped.
+      entire table, unless <literal>NOT VALID</literal> is specified;
+      however, if a valid <literal>CHECK</literal> constraint exists
+      (and is not dropped in the same command) which proves no
+      <literal>NULL</literal> can exist, then the table scan is skipped.
       If a column has an invalid not-null constraint,
       <literal>SET NOT NULL</literal> validates it.
      </para>
@@ -852,7 +853,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
 
      <para>
       <literal>SHARE UPDATE EXCLUSIVE</literal> lock will be taken for
-      fillfactor, toast and autovacuum storage parameters, as well as the
+      fillfactor, TOAST and autovacuum storage parameters, as well as the
       planner parameter <varname>parallel_workers</varname>.
      </para>
     </listitem>
diff --git a/doc/src/sgml/ref/checkpoint.sgml b/doc/src/sgml/ref/checkpoint.sgml
index db011a47d0458..cd981cf2cab9f 100644
--- a/doc/src/sgml/ref/checkpoint.sgml
+++ b/doc/src/sgml/ref/checkpoint.sgml
@@ -21,7 +21,12 @@ PostgreSQL documentation
 
  <refsynopsisdiv>
 <synopsis>
-CHECKPOINT
+CHECKPOINT [ ( option [, ...] ) ]
+
+<phrase>where <replaceable class="parameter">option</replaceable> can be one of:</phrase>
+
+    FLUSH_UNLOGGED [ <replaceable class="parameter">boolean</replaceable> ]
+    MODE { FAST | SPREAD }
 </synopsis>
  </refsynopsisdiv>
 
@@ -37,14 +42,24 @@ CHECKPOINT
   </para>
 
   <para>
-   The <command>CHECKPOINT</command> command forces an immediate
+   By default, the <command>CHECKPOINT</command> command forces a fast
    checkpoint when the command is issued, without waiting for a
    regular checkpoint scheduled by the system (controlled by the settings in
    <xref linkend="runtime-config-wal-checkpoints"/>).
+   To request the checkpoint be spread over a longer interval, set the
+   <literal>MODE</literal> option to <literal>SPREAD</literal>.
    <command>CHECKPOINT</command> is not intended for use during normal
    operation.
   </para>
 
+  <para>
+   The server may consolidate concurrently requested checkpoints.  Such
+   consolidated requests will contain a combined set of options.  For example,
+   if one session requests a fast checkpoint and another requests a spread
+   checkpoint, the server may combine those requests and perform one fast
+   checkpoint.
+  </para>
+
   <para>
    If executed during recovery, the <command>CHECKPOINT</command> command
    will force a restartpoint (see <xref linkend="wal-configuration"/>)
@@ -58,6 +73,55 @@ CHECKPOINT
   </para>
  </refsect1>
 
+ <refsect1>
+  <title>Parameters</title>
+
+  <variablelist>
+   <varlistentry>
+    <term><literal>FLUSH_UNLOGGED</literal></term>
+    <listitem>
+     <para>
+      Normally, <command>CHECKPOINT</command> does not flush dirty buffers of
+      unlogged relations.  This option, which is disabled by default, enables
+      flushing unlogged relations to disk.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><literal>MODE</literal></term>
+    <listitem>
+     <para>
+      When set to <literal>FAST</literal>, which is the default, the requested
+      checkpoint will be completed as fast as possible, which may result in a
+      significantly higher rate of I/O during the checkpoint.
+     </para>
+     <para>
+      <literal>MODE</literal> can also be set to <literal>SPREAD</literal> to
+      request the checkpoint be spread over a longer interval (controlled via
+      the settings in <xref linkend="runtime-config-wal-checkpoints"/>), like a
+      regular checkpoint scheduled by the system.  This can reduce the rate of
+      I/O during the checkpoint.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><replaceable class="parameter">boolean</replaceable></term>
+    <listitem>
+     <para>
+      Specifies whether the selected option should be turned on or off.
+      You can write <literal>TRUE</literal>, <literal>ON</literal>, or
+      <literal>1</literal> to enable the option, and <literal>FALSE</literal>,
+      <literal>OFF</literal>, or <literal>0</literal> to disable it.  The
+      <replaceable class="parameter">boolean</replaceable> value can also
+      be omitted, in which case <literal>TRUE</literal> is assumed.
+     </para>
+    </listitem>
+   </varlistentry>
+  </variablelist>
+ </refsect1>
+
  <refsect1>
   <title>Compatibility</title>
 
diff --git a/doc/src/sgml/ref/copy.sgml b/doc/src/sgml/ref/copy.sgml
index 8433344e5b6f5..c2d1fbc1fbe94 100644
--- a/doc/src/sgml/ref/copy.sgml
+++ b/doc/src/sgml/ref/copy.sgml
@@ -37,7 +37,7 @@ COPY { <replaceable class="parameter">table_name</replaceable> [ ( <replaceable
     DELIMITER '<replaceable class="parameter">delimiter_character</replaceable>'
     NULL '<replaceable class="parameter">null_string</replaceable>'
     DEFAULT '<replaceable class="parameter">default_string</replaceable>'
-    HEADER [ <replaceable class="parameter">boolean</replaceable> | MATCH ]
+    HEADER [ <replaceable class="parameter">boolean</replaceable> | <replaceable class="parameter">integer</replaceable> | MATCH ]
     QUOTE '<replaceable class="parameter">quote_character</replaceable>'
     ESCAPE '<replaceable class="parameter">escape_character</replaceable>'
     FORCE_QUOTE { ( <replaceable class="parameter">column_name</replaceable> [, ...] ) | * }
@@ -212,6 +212,15 @@ COPY { <replaceable class="parameter">table_name</replaceable> [ ( <replaceable
     </listitem>
    </varlistentry>
 
+   <varlistentry>
+    <term><replaceable class="parameter">integer</replaceable></term>
+    <listitem>
+     <para>
+      Specifies a non-negative integer value passed to the selected option.
+     </para>
+    </listitem>
+   </varlistentry>
+
    <varlistentry>
     <term><literal>FORMAT</literal></term>
     <listitem>
@@ -303,16 +312,25 @@ COPY { <replaceable class="parameter">table_name</replaceable> [ ( <replaceable
     <term><literal>HEADER</literal></term>
     <listitem>
      <para>
-      Specifies that the file contains a header line with the names of each
-      column in the file.  On output, the first line contains the column
-      names from the table.  On input, the first line is discarded when this
-      option is set to <literal>true</literal> (or equivalent Boolean value).
-      If this option is set to <literal>MATCH</literal>, the number and names
-      of the columns in the header line must match the actual column names of
-      the table, in order;  otherwise an error is raised.
+      On output, if this option is set to <literal>true</literal>
+      (or an equivalent Boolean value), the first line of the output will
+      contain the column names from the table.
+      Integer values <literal>0</literal> and <literal>1</literal> are
+      accepted as Boolean values, but other integers are not allowed for
+      <command>COPY TO</command> commands.
+     </para>
+     <para>
+      On input, if this option is set to <literal>true</literal>
+      (or an equivalent Boolean value), the first line of the input is
+      discarded.  If set to a non-negative integer, that number of
+      lines are discarded.  If set to <literal>MATCH</literal>, the first line
+      is discarded, and it must contain column names that exactly match the
+      table's columns, in both number and order; otherwise, an error is raised.
+      The <literal>MATCH</literal> value is only valid for
+      <command>COPY FROM</command> commands.
+     </para>
+     <para>
       This option is not allowed when using <literal>binary</literal> format.
-      The <literal>MATCH</literal> option is only valid for <command>COPY
-      FROM</command> commands.
      </para>
     </listitem>
    </varlistentry>
diff --git a/doc/src/sgml/ref/create_database.sgml b/doc/src/sgml/ref/create_database.sgml
index 4da8aeebb50a2..3544b15efdafa 100644
--- a/doc/src/sgml/ref/create_database.sgml
+++ b/doc/src/sgml/ref/create_database.sgml
@@ -150,12 +150,12 @@ CREATE DATABASE <replaceable class="parameter">name</replaceable>
        <para>
         Sets the default collation order and character classification in the
         new database.  Collation affects the sort order applied to strings,
-        e.g., in queries with <literal>ORDER BY</literal>, as well as the order used in indexes
-        on text columns.  Character classification affects the categorization
-        of characters, e.g., lower, upper, and digit.  Also sets the
-        associated aspects of the operating system environment,
-        <literal>LC_COLLATE</literal> and <literal>LC_CTYPE</literal>.  The
-        default is the same setting as the template database.  See <xref
+        e.g., in queries with <literal>ORDER BY</literal>, as well as the
+        order used in indexes on text columns.  Character classification
+        affects the categorization of characters, e.g., lower, upper, and
+        digit.  Also sets the <literal>LC_CTYPE</literal> aspect of the
+        operating system environment.  The default is the same setting as the
+        template database.  See <xref
         linkend="collation-managing-create-libc"/> and <xref
         linkend="collation-managing-create-icu"/> for details.
        </para>
@@ -189,17 +189,16 @@ CREATE DATABASE <replaceable class="parameter">name</replaceable>
       <term><replaceable class="parameter">lc_collate</replaceable></term>
       <listitem>
        <para>
-        Sets <literal>LC_COLLATE</literal> in the database server's operating
-        system environment.  The default is the setting of <xref
-        linkend="create-database-locale"/> if specified, otherwise the same
-        setting as the template database.  See below for additional
-        restrictions.
+        If <xref linkend="create-database-locale-provider"/> is
+        <literal>libc</literal>, sets the default collation order to use in
+        the new database, overriding the setting <xref
+        linkend="create-database-locale"/>. Otherwise, this setting is
+        ignored.
        </para>
        <para>
-        If <xref linkend="create-database-locale-provider"/> is
-        <literal>libc</literal>, also sets the default collation order to use
-        in the new database, overriding the setting <xref
-        linkend="create-database-locale"/>.
+        The default is the setting of <xref linkend="create-database-locale"/>
+        if specified, otherwise the same setting as the template database.
+        See below for additional restrictions.
        </para>
       </listitem>
      </varlistentry>
@@ -208,16 +207,18 @@ CREATE DATABASE <replaceable class="parameter">name</replaceable>
       <listitem>
        <para>
         Sets <literal>LC_CTYPE</literal> in the database server's operating
-        system environment.  The default is the setting of <xref
-        linkend="create-database-locale"/> if specified, otherwise the same
-        setting as the template database.  See below for additional
-        restrictions.
+        system environment.
        </para>
        <para>
         If <xref linkend="create-database-locale-provider"/> is
-        <literal>libc</literal>, also sets the default character
-        classification to use in the new database, overriding the setting
-        <xref linkend="create-database-locale"/>.
+        <literal>libc</literal>, sets the default character classification to
+        use in the new database, overriding the setting <xref
+        linkend="create-database-locale"/>.
+       </para>
+       <para>
+        The default is the setting of <xref linkend="create-database-locale"/>
+        if specified, otherwise the same setting as the template database.
+        See below for additional restrictions.
        </para>
       </listitem>
      </varlistentry>
diff --git a/doc/src/sgml/ref/create_operator.sgml b/doc/src/sgml/ref/create_operator.sgml
index 3553d36454185..d2ffb1b2a500f 100644
--- a/doc/src/sgml/ref/create_operator.sgml
+++ b/doc/src/sgml/ref/create_operator.sgml
@@ -23,7 +23,7 @@ PostgreSQL documentation
 <synopsis>
 CREATE OPERATOR <replaceable>name</replaceable> (
     {FUNCTION|PROCEDURE} = <replaceable class="parameter">function_name</replaceable>
-    [, LEFTARG = <replaceable class="parameter">left_type</replaceable> ] [, RIGHTARG = <replaceable class="parameter">right_type</replaceable> ]
+    [, LEFTARG = <replaceable class="parameter">left_type</replaceable> ] , RIGHTARG = <replaceable class="parameter">right_type</replaceable>
     [, COMMUTATOR = <replaceable class="parameter">com_op</replaceable> ] [, NEGATOR = <replaceable class="parameter">neg_op</replaceable> ]
     [, RESTRICT = <replaceable class="parameter">res_proc</replaceable> ] [, JOIN = <replaceable class="parameter">join_proc</replaceable> ]
     [, HASHES ] [, MERGES ]
@@ -88,8 +88,8 @@ CREATE OPERATOR <replaceable>name</replaceable> (
 
   <para>
    For binary operators, both <literal>LEFTARG</literal> and
-   <literal>RIGHTARG</literal> must be defined.  For prefix operators only
-   <literal>RIGHTARG</literal> should be defined.
+   <literal>RIGHTARG</literal> must be defined.  For prefix operators, only
+   <literal>RIGHTARG</literal> must be defined.
    The <replaceable class="parameter">function_name</replaceable>
    function must have been previously defined using <command>CREATE
    FUNCTION</command> and must be defined to accept the correct number
diff --git a/doc/src/sgml/ref/create_subscription.sgml b/doc/src/sgml/ref/create_subscription.sgml
index 57dec28a5df64..247c5bd260410 100644
--- a/doc/src/sgml/ref/create_subscription.sgml
+++ b/doc/src/sgml/ref/create_subscription.sgml
@@ -169,7 +169,9 @@ CREATE SUBSCRIPTION <replaceable class="parameter">subscription_name</replaceabl
         <listitem>
          <para>
           Name of the publisher's replication slot to use.  The default is
-          to use the name of the subscription for the slot name.
+          to use the name of the subscription for the slot name. The name cannot
+          be <literal>pg_conflict_detection</literal> as it is reserved for the
+          conflict detection.
          </para>
 
          <para>
@@ -435,6 +437,90 @@ CREATE SUBSCRIPTION <replaceable class="parameter">subscription_name</replaceabl
          </para>
         </listitem>
        </varlistentry>
+
+      <varlistentry id="sql-createsubscription-params-with-retain-dead-tuples">
+        <term><literal>retain_dead_tuples</literal> (<type>boolean</type>)</term>
+        <listitem>
+         <para>
+          Specifies whether the information (e.g., dead tuples, commit
+          timestamps, and origins) required for conflict detection on the
+          subscriber is retained. The default is <literal>false</literal>.
+          If set to <literal>true</literal>, the detection of
+          <xref linkend="conflict-update-deleted"/> is enabled, and a physical
+          replication slot named <quote><literal>pg_conflict_detection</literal></quote>
+          created on the subscriber to prevent the information for detecting
+          conflicts from being removed.
+         </para>
+
+         <para>
+          Note that the information useful for conflict detection is retained
+          only after the creation of the slot. You can verify the existence of
+          this slot by querying <link linkend="view-pg-replication-slots">pg_replication_slots</link>.
+          And even if multiple subscriptions on one node enable this option,
+          only one replication slot will be created. Also,
+          <varname>wal_level</varname> must be set to <literal>replica</literal>
+          or higher to allow the replication slot to be used.
+         </para>
+
+         <caution>
+          <para>
+           Note that the information for conflict detection cannot be purged if
+           the subscription is disabled; thus, the information will accumulate
+           until the subscription is enabled. To prevent excessive accumulation,
+           it is recommended to disable <literal>retain_dead_tuples</literal>
+           if the subscription will be inactive for an extended period.
+          </para>
+
+          <para>
+           Additionally when enabling <literal>retain_dead_tuples</literal> for
+           conflict detection in logical replication, it is important to design the
+           replication topology to balance data retention requirements with
+           overall system performance. This option provides minimal performance
+           overhead when applied appropriately. The following scenarios illustrate
+           effective usage patterns when enabling this option.
+          </para>
+
+          <para>
+           a. Large Tables with Bidirectional Writes:
+           For large tables subject to concurrent writes on both publisher and
+           subscriber nodes, publishers can define row filters when creating
+           publications to segment data. This allows multiple subscriptions
+           to replicate exclusive subsets of the table in parallel, optimizing
+           the throughput.
+          </para>
+
+          <para>
+           b. Write-Enabled Subscribers:
+           If a subscriber node is expected to perform write operations, replication
+           can be structured using multiple publications and subscriptions. By
+           distributing tables across these publications, the workload is spread among
+           several apply workers, improving concurrency and reducing contention.
+          </para>
+
+          <para>
+           c. Read-Only Subscribers:
+           In configurations involving single or multiple publisher nodes
+           performing concurrent write operations, read-only subscriber nodes may
+           replicate changes without seeing a performance impact if it does index
+           scan. However, if the subscriber is impacted due to replication lag or
+           scan performance (say due to sequential scans), it needs to follow one
+           of the two previous strategies to distribute the workload on the
+           subscriber.
+          </para>
+         </caution>
+
+         <para>
+          This option cannot be enabled if the publisher is a physical standby.
+         </para>
+
+         <para>
+          Enabling this option ensures retention of information useful for
+          conflict detection solely for changes occurring locally on the
+          publisher. For the changes originating from different origins,
+          reliable conflict detection cannot be guaranteed.
+         </para>
+        </listitem>
+       </varlistentry>
       </variablelist></para>
 
     </listitem>
diff --git a/doc/src/sgml/ref/create_trigger.sgml b/doc/src/sgml/ref/create_trigger.sgml
index 982ab6f3ee450..0d8d463479bc1 100644
--- a/doc/src/sgml/ref/create_trigger.sgml
+++ b/doc/src/sgml/ref/create_trigger.sgml
@@ -29,7 +29,7 @@ PostgreSQL documentation
 CREATE [ OR REPLACE ] [ CONSTRAINT ] TRIGGER <replaceable class="parameter">name</replaceable> { BEFORE | AFTER | INSTEAD OF } { <replaceable class="parameter">event</replaceable> [ OR ... ] }
     ON <replaceable class="parameter">table_name</replaceable>
     [ FROM <replaceable class="parameter">referenced_table_name</replaceable> ]
-    [ NOT DEFERRABLE | [ DEFERRABLE ] [ INITIALLY IMMEDIATE | INITIALLY DEFERRED ] ]
+    [ NOT DEFERRABLE | [ DEFERRABLE ] [ INITIALLY IMMEDIATE | INITIALLY DEFERRED ] ] [ ENFORCED ]
     [ REFERENCING { { OLD | NEW } TABLE [ AS ] <replaceable class="parameter">transition_relation_name</replaceable> } [ ... ] ]
     [ FOR [ EACH ] { ROW | STATEMENT } ]
     [ WHEN ( <replaceable class="parameter">condition</replaceable> ) ]
@@ -197,9 +197,11 @@ CREATE [ OR REPLACE ] [ CONSTRAINT ] TRIGGER <replaceable class="parameter">name
    of the rows inserted, deleted, or modified by the current SQL statement.
    This feature lets the trigger see a global view of what the statement did,
    not just one row at a time.  This option is only allowed for
-   an <literal>AFTER</literal> trigger that is not a constraint trigger; also, if
-   the trigger is an <literal>UPDATE</literal> trigger, it must not specify
-   a <replaceable class="parameter">column_name</replaceable> list.
+   an <literal>AFTER</literal> trigger on a plain table (not a foreign table).
+   The trigger should not be a constraint trigger.  Also, if the trigger is
+   an <literal>UPDATE</literal> trigger, it must not specify
+   a <replaceable class="parameter">column_name</replaceable> list when using
+   this option.
    <literal>OLD TABLE</literal> may only be specified once, and only for a trigger
    that can fire on <literal>UPDATE</literal> or <literal>DELETE</literal>; it creates a
    transition relation containing the <firstterm>before-images</firstterm> of all rows
@@ -321,6 +323,15 @@ UPDATE OF <replaceable>column_name1</replaceable> [, <replaceable>column_name2</
     </listitem>
    </varlistentry>
 
+   <varlistentry>
+    <term><literal>ENFORCED</literal></term>
+    <listitem>
+     <para>
+      This is a noise word.  Constraint triggers are always enforced.
+     </para>
+    </listitem>
+   </varlistentry>
+
    <varlistentry>
     <term><literal>REFERENCING</literal></term>
     <listitem>
diff --git a/doc/src/sgml/ref/createdb.sgml b/doc/src/sgml/ref/createdb.sgml
index 5c4e0465ed9da..2ccbe13f39008 100644
--- a/doc/src/sgml/ref/createdb.sgml
+++ b/doc/src/sgml/ref/createdb.sgml
@@ -136,7 +136,8 @@ PostgreSQL documentation
       <term><option>--lc-collate=<replaceable class="parameter">locale</replaceable></option></term>
       <listitem>
        <para>
-        Specifies the LC_COLLATE setting to be used in this database.
+        Specifies the LC_COLLATE setting to be used in this database (ignored
+        unless the locale provider is <literal>libc</literal>).
        </para>
       </listitem>
      </varlistentry>
diff --git a/doc/src/sgml/ref/pg_amcheck.sgml b/doc/src/sgml/ref/pg_amcheck.sgml
index 6bfe28799c4e6..ef2bdfd19ae5d 100644
--- a/doc/src/sgml/ref/pg_amcheck.sgml
+++ b/doc/src/sgml/ref/pg_amcheck.sgml
@@ -41,7 +41,7 @@ PostgreSQL documentation
   </para>
 
   <para>
-   Only ordinary and toast table relations, materialized views, sequences, and
+   Only ordinary and TOAST table relations, materialized views, sequences, and
    btree indexes are currently supported.  Other relation types are silently
    skipped.
   </para>
@@ -276,7 +276,7 @@ PostgreSQL documentation
      <term><option>--no-dependent-toast</option></term>
      <listitem>
       <para>
-       By default, if a table is checked, its toast table, if any, will also
+       By default, if a table is checked, its TOAST table, if any, will also
        be checked, even if it is not explicitly selected by an option
        such as <literal>--table</literal> or <literal>--relation</literal>.
        This option suppresses that behavior.
@@ -306,9 +306,9 @@ PostgreSQL documentation
      <term><option>--exclude-toast-pointers</option></term>
      <listitem>
       <para>
-       By default, whenever a toast pointer is encountered in a table,
+       By default, whenever a TOAST pointer is encountered in a table,
        a lookup is performed to ensure that it references apparently-valid
-       entries in the toast table. These checks can be quite slow, and this
+       entries in the TOAST table. These checks can be quite slow, and this
        option can be used to skip them.
       </para>
      </listitem>
@@ -368,9 +368,9 @@ PostgreSQL documentation
        End checking at the specified block number.  An error will occur if the
        table relation being checked has fewer than this number of blocks.
        This option does not apply to indexes, and is probably only useful when
-       checking a single table relation. If both a regular table and a toast
+       checking a single table relation. If both a regular table and a TOAST
        table are checked, this option will apply to both, but higher-numbered
-       toast blocks may still be accessed while validating toast pointers,
+       TOAST blocks may still be accessed while validating TOAST pointers,
        unless that is suppressed using
        <option>--exclude-toast-pointers</option>.
       </para>
diff --git a/doc/src/sgml/ref/pg_basebackup.sgml b/doc/src/sgml/ref/pg_basebackup.sgml
index 9659f76042c5b..fecee08b0a536 100644
--- a/doc/src/sgml/ref/pg_basebackup.sgml
+++ b/doc/src/sgml/ref/pg_basebackup.sgml
@@ -500,8 +500,9 @@ PostgreSQL documentation
       <term><option>--checkpoint={fast|spread}</option></term>
       <listitem>
        <para>
-        Sets checkpoint mode to fast (immediate) or spread (the default)
+        Sets checkpoint mode to fast or spread
         (see <xref linkend="backup-lowlevel-base-backup"/>).
+        The default is spread.
        </para>
       </listitem>
      </varlistentry>
diff --git a/doc/src/sgml/ref/pg_dump.sgml b/doc/src/sgml/ref/pg_dump.sgml
index 2ae084b5fa6fc..0bc7609bdf815 100644
--- a/doc/src/sgml/ref/pg_dump.sgml
+++ b/doc/src/sgml/ref/pg_dump.sgml
@@ -1354,6 +1354,15 @@ PostgreSQL documentation
        </listitem>
      </varlistentry>
 
+     <varlistentry>
+      <term><option>--statistics</option></term>
+      <listitem>
+       <para>
+        Dump statistics.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry>
       <term><option>--statistics-only</option></term>
       <listitem>
@@ -1440,33 +1449,6 @@ PostgreSQL documentation
       </listitem>
      </varlistentry>
 
-     <varlistentry>
-      <term><option>--with-data</option></term>
-      <listitem>
-       <para>
-        Dump data. This is the default.
-       </para>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><option>--with-schema</option></term>
-      <listitem>
-       <para>
-        Dump schema (data definitions). This is the default.
-       </para>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><option>--with-statistics</option></term>
-      <listitem>
-       <para>
-        Dump statistics.
-       </para>
-      </listitem>
-     </varlistentry>
-
      <varlistentry>
        <term><option>-?</option></term>
        <term><option>--help</option></term>
@@ -1682,7 +1664,7 @@ CREATE DATABASE foo WITH TEMPLATE template0;
   </para>
 
   <para>
-   If <option>--with-statistics</option> is specified,
+   If <option>--statistics</option> is specified,
    <command>pg_dump</command> will include most optimizer statistics in the
    resulting dump file.  However, some statistics may not be included, such as
    those created explicitly with <xref linkend="sql-createstatistics"/> or
diff --git a/doc/src/sgml/ref/pg_dumpall.sgml b/doc/src/sgml/ref/pg_dumpall.sgml
index 8ca68da5a5560..364442f00f28e 100644
--- a/doc/src/sgml/ref/pg_dumpall.sgml
+++ b/doc/src/sgml/ref/pg_dumpall.sgml
@@ -16,10 +16,7 @@ PostgreSQL documentation
 
  <refnamediv>
   <refname>pg_dumpall</refname>
-
-  <refpurpose>
-   export a <productname>PostgreSQL</productname> database cluster as an SQL script or to other formats
-  </refpurpose>
+  <refpurpose>extract a <productname>PostgreSQL</productname> database cluster into a script file</refpurpose>
  </refnamediv>
 
  <refsynopsisdiv>
@@ -36,7 +33,7 @@ PostgreSQL documentation
   <para>
    <application>pg_dumpall</application> is a utility for writing out
    (<quote>dumping</quote>) all <productname>PostgreSQL</productname> databases
-   of a cluster into an SQL script file or an archive.  The output contains
+   of a cluster into one script file.  The script file contains
    <acronym>SQL</acronym> commands that can be used as input to <xref
    linkend="app-psql"/> to restore the databases.  It does this by
    calling <xref linkend="app-pgdump"/> for each database in the cluster.
@@ -55,16 +52,11 @@ PostgreSQL documentation
   </para>
 
   <para>
-   Plain text SQL scripts will be written to the standard output.  Use the
+   The SQL script will be written to the standard output.  Use the
    <option>-f</option>/<option>--file</option> option or shell operators to
    redirect it into a file.
   </para>
 
-  <para>
-   Archives in other formats will be placed in a directory named using the
-   <option>-f</option>/<option>--file</option>, which is required in this case.
-  </para>
-
   <para>
   <application>pg_dumpall</application> needs to connect several
   times to the <productname>PostgreSQL</productname> server (once per
@@ -129,85 +121,10 @@ PostgreSQL documentation
        <para>
         Send output to the specified file.  If this is omitted, the
         standard output is used.
-        Note: This option can only be omitted when <option>--format</option> is plain
        </para>
       </listitem>
      </varlistentry>
 
-     <varlistentry>
-      <term><option>-F <replaceable class="parameter">format</replaceable></option></term>
-      <term><option>--format=<replaceable class="parameter">format</replaceable></option></term>
-      <listitem>
-       <para>
-        Specify the format of dump files.  In plain format, all the dump data is
-        sent in a single text stream. This is the default.
-
-        In all other modes, <application>pg_dumpall</application> first creates two files:
-        <filename>global.dat</filename> and <filename>map.dat</filename>, in the directory
-        specified by <option>--file</option>.
-        The first file contains global data, such as roles and tablespaces. The second
-        contains a mapping between database oids and names. These files are used by
-        <application>pg_restore</application>. Data for individual databases is placed in
-        <filename>databases</filename> subdirectory, named using the database's <type>oid</type>.
-
-       <variablelist>
-        <varlistentry>
-         <term><literal>d</literal></term>
-         <term><literal>directory</literal></term>
-         <listitem>
-          <para>
-           Output directory-format archives for each database,
-           suitable for input into pg_restore. The directory
-           will have database <type>oid</type> as its name.
-          </para>
-         </listitem>
-        </varlistentry>
-
-        <varlistentry>
-         <term><literal>p</literal></term>
-         <term><literal>plain</literal></term>
-         <listitem>
-          <para>
-           Output a plain-text SQL script file (the default).
-          </para>
-         </listitem>
-        </varlistentry>
-
-        <varlistentry>
-         <term><literal>c</literal></term>
-         <term><literal>custom</literal></term>
-         <listitem>
-          <para>
-           Output a custom-format archive for each database,
-           suitable for input into pg_restore. The archive
-           will be named <filename>dboid.dmp</filename> where <type>dboid</type> is the
-           <type>oid</type> of the database.
-          </para>
-         </listitem>
-        </varlistentry>
-
-         <varlistentry>
-         <term><literal>t</literal></term>
-         <term><literal>tar</literal></term>
-         <listitem>
-          <para>
-           Output a tar-format archive for each database,
-           suitable for input into pg_restore. The archive
-           will be named <filename>dboid.tar</filename> where <type>dboid</type> is the
-           <type>oid</type> of the database.
-          </para>
-         </listitem>
-        </varlistentry>
-
-        </variablelist>
-
-       Note: see <xref linkend="app-pgdump"/> for details
-       of how the various non plain text archives work.
-
-        </para>
-      </listitem>
-     </varlistentry>
-
      <varlistentry>
       <term><option>-g</option></term>
       <term><option>--globals-only</option></term>
@@ -688,6 +605,15 @@ exclude database <replaceable class="parameter">PATTERN</replaceable>
       </listitem>
      </varlistentry>
 
+     <varlistentry>
+      <term><option>--statistics</option></term>
+      <listitem>
+       <para>
+        Dump statistics.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry>
       <term><option>--statistics-only</option></term>
       <listitem>
@@ -723,33 +649,6 @@ exclude database <replaceable class="parameter">PATTERN</replaceable>
       </listitem>
      </varlistentry>
 
-     <varlistentry>
-      <term><option>--with-data</option></term>
-      <listitem>
-       <para>
-        Dump data. This is the default.
-       </para>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><option>--with-schema</option></term>
-      <listitem>
-       <para>
-        Dump schema (data definitions). This is the default.
-       </para>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><option>--with-statistics</option></term>
-      <listitem>
-       <para>
-        Dump statistics.
-       </para>
-      </listitem>
-     </varlistentry>
-
      <varlistentry>
        <term><option>-?</option></term>
        <term><option>--help</option></term>
@@ -961,7 +860,7 @@ exclude database <replaceable class="parameter">PATTERN</replaceable>
   </para>
 
   <para>
-   If <option>--with-statistics</option> is specified,
+   If <option>--statistics</option> is specified,
    <command>pg_dumpall</command> will include most optimizer statistics in the
    resulting dump file.  However, some statistics may not be included, such as
    those created explicitly with <xref linkend="sql-createstatistics"/> or
diff --git a/doc/src/sgml/ref/pg_recvlogical.sgml b/doc/src/sgml/ref/pg_recvlogical.sgml
index f68182266a9fa..263ebdeeab4a8 100644
--- a/doc/src/sgml/ref/pg_recvlogical.sgml
+++ b/doc/src/sgml/ref/pg_recvlogical.sgml
@@ -53,6 +53,16 @@ PostgreSQL documentation
    (<keycombo action="simul"><keycap>Control</keycap><keycap>C</keycap></keycombo>)
    or <systemitem>SIGTERM</systemitem> signal.
   </para>
+
+  <para>
+   When <application>pg_recvlogical</application> receives
+   a <systemitem>SIGHUP</systemitem> signal, it closes the current output file
+   and opens a new one using the filename specified by
+   the <option>--file</option> option.  This allows us to rotate
+   the output file by first renaming the current file and then sending
+   a <systemitem>SIGHUP</systemitem> signal to
+   <application>pg_recvlogical</application>.
+  </para>
  </refsect1>
 
  <refsect1>
diff --git a/doc/src/sgml/ref/pg_restore.sgml b/doc/src/sgml/ref/pg_restore.sgml
index b649bd3a5ae0f..261ead1503955 100644
--- a/doc/src/sgml/ref/pg_restore.sgml
+++ b/doc/src/sgml/ref/pg_restore.sgml
@@ -18,9 +18,8 @@ PostgreSQL documentation
   <refname>pg_restore</refname>
 
   <refpurpose>
-   restore <productname>PostgreSQL</productname> databases from archives
-   created by <application>pg_dump</application> or
-   <application>pg_dumpall</application>
+   restore a <productname>PostgreSQL</productname> database from an
+   archive file created by <application>pg_dump</application>
   </refpurpose>
  </refnamediv>
 
@@ -39,14 +38,13 @@ PostgreSQL documentation
 
   <para>
    <application>pg_restore</application> is a utility for restoring a
-   <productname>PostgreSQL</productname> database or cluster from an archive
-   created by <xref linkend="app-pgdump"/> or
-   <xref linkend="app-pg-dumpall"/> in one of the non-plain-text
+   <productname>PostgreSQL</productname> database from an archive
+   created by <xref linkend="app-pgdump"/> in one of the non-plain-text
    formats.  It will issue the commands necessary to reconstruct the
-   database or cluster to the state it was in at the time it was saved. The
-   archives also allow <application>pg_restore</application> to
+   database to the state it was in at the time it was saved.  The
+   archive files also allow <application>pg_restore</application> to
    be selective about what is restored, or even to reorder the items
-   prior to being restored. The archive formats are designed to be
+   prior to being restored. The archive files are designed to be
    portable across architectures.
   </para>
 
@@ -54,17 +52,10 @@ PostgreSQL documentation
    <application>pg_restore</application> can operate in two modes.
    If a database name is specified, <application>pg_restore</application>
    connects to that database and restores archive contents directly into
-   the database.
-   When restoring from a dump made by <application>pg_dumpall</application>,
-   each database will be created and then the restoration will be run in that
-   database.
-
-   Otherwise, when a database name is not specified, a script containing the SQL
-   commands necessary to rebuild the database or cluster is created and written
+   the database.  Otherwise, a script containing the SQL
+   commands necessary to rebuild the database is created and written
    to a file or standard output.  This script output is equivalent to
-   the plain text output format of <application>pg_dump</application> or
-   <application>pg_dumpall</application>.
-
+   the plain text output format of <application>pg_dump</application>.
    Some of the options controlling the output are therefore analogous to
    <application>pg_dump</application> options.
   </para>
@@ -149,8 +140,6 @@ PostgreSQL documentation
         commands that mention this database.
         Access privileges for the database itself are also restored,
         unless <option>--no-acl</option> is specified.
-        <option>--create</option> is required when restoring multiple databases
-        from an archive created by <application>pg_dumpall</application>.
        </para>
 
        <para>
@@ -246,19 +235,6 @@ PostgreSQL documentation
       </listitem>
      </varlistentry>
 
-     <varlistentry>
-      <term><option>-g</option></term>
-      <term><option>--globals-only</option></term>
-      <listitem>
-       <para>
-        Restore only global objects (roles and tablespaces), no databases.
-       </para>
-       <para>
-        This option is only relevant when restoring from an archive made using <application>pg_dumpall</application>.
-       </para>
-      </listitem>
-     </varlistentry>
-
      <varlistentry>
       <term><option>-I <replaceable class="parameter">index</replaceable></option></term>
       <term><option>--index=<replaceable class="parameter">index</replaceable></option></term>
@@ -603,28 +579,6 @@ PostgreSQL documentation
       </listitem>
      </varlistentry>
 
-     <varlistentry>
-      <term><option>--exclude-database=<replaceable class="parameter">pattern</replaceable></option></term>
-      <listitem>
-       <para>
-        Do not restore databases whose name matches
-        <replaceable class="parameter">pattern</replaceable>.
-        Multiple patterns can be excluded by writing multiple
-        <option>--exclude-database</option> switches.  The
-        <replaceable class="parameter">pattern</replaceable> parameter is
-        interpreted as a pattern according to the same rules used by
-        <application>psql</application>'s <literal>\d</literal>
-        commands (see <xref linkend="app-psql-patterns"/>),
-        so multiple databases can also be excluded by writing wildcard
-        characters in the pattern.  When using wildcards, be careful to
-        quote the pattern if needed to prevent shell wildcard expansion.
-       </para>
-       <para>
-        This option is only relevant when restoring from an archive made using <application>pg_dumpall</application>.
-       </para>
-      </listitem>
-     </varlistentry>
-
      <varlistentry>
       <term><option>--filter=<replaceable class="parameter">filename</replaceable></option></term>
       <listitem>
@@ -861,6 +815,16 @@ PostgreSQL documentation
        </listitem>
      </varlistentry>
 
+     <varlistentry>
+      <term><option>--statistics</option></term>
+      <listitem>
+       <para>
+        Output commands to restore statistics, if the archive contains them.
+        This is the default.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry>
       <term><option>--statistics-only</option></term>
       <listitem>
@@ -919,36 +883,6 @@ PostgreSQL documentation
       </listitem>
      </varlistentry>
 
-     <varlistentry>
-      <term><option>--with-data</option></term>
-      <listitem>
-       <para>
-        Output commands to restore data, if the archive contains them.
-        This is the default.
-       </para>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><option>--with-schema</option></term>
-      <listitem>
-       <para>
-        Output commands to restore schema (data definitions), if the archive
-        contains them. This is the default.
-       </para>
-      </listitem>
-     </varlistentry>
-
-     <varlistentry>
-      <term><option>--with-statistics</option></term>
-      <listitem>
-       <para>
-        Output commands to restore statistics, if the archive contains them.
-        This is the default.
-       </para>
-      </listitem>
-     </varlistentry>
-
      <varlistentry>
        <term><option>-?</option></term>
        <term><option>--help</option></term>
diff --git a/doc/src/sgml/ref/pgtesttiming.sgml b/doc/src/sgml/ref/pgtesttiming.sgml
index a5eb3aa25e02f..afe6a12be4b30 100644
--- a/doc/src/sgml/ref/pgtesttiming.sgml
+++ b/doc/src/sgml/ref/pgtesttiming.sgml
@@ -30,11 +30,23 @@ PostgreSQL documentation
   <title>Description</title>
 
  <para>
-  <application>pg_test_timing</application> is a tool to measure the timing overhead
-  on your system and confirm that the system time never moves backwards.
+  <application>pg_test_timing</application> is a tool to measure the
+  timing overhead on your system and confirm that the system time never
+  moves backwards.  It simply reads the system clock over and over again
+  as fast as it can for a specified length of time, and then prints
+  statistics about the observed differences in successive clock readings.
+ </para>
+ <para>
+  Smaller (but not zero) differences are better, since they imply both
+  more-precise clock hardware and less overhead to collect a clock reading.
   Systems that are slow to collect timing data can give less accurate
   <command>EXPLAIN ANALYZE</command> results.
  </para>
+ <para>
+  This tool is also helpful to determine if
+  the <varname>track_io_timing</varname> configuration parameter is likely
+  to produce useful results.
+ </para>
  </refsect1>
 
  <refsect1>
@@ -59,6 +71,21 @@ PostgreSQL documentation
       </listitem>
      </varlistentry>
 
+     <varlistentry>
+      <term><option>-c <replaceable class="parameter">cutoff</replaceable></option></term>
+      <term><option>--cutoff=<replaceable class="parameter">cutoff</replaceable></option></term>
+      <listitem>
+       <para>
+        Specifies the cutoff percentage for the list of exact observed
+        timing durations (that is, the changes in the system clock value
+        from one reading to the next).  The list will end once the running
+        percentage total reaches or exceeds this value, except that the
+        largest observed duration will always be printed.  The default
+        cutoff is 99.99.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry>
       <term><option>-V</option></term>
       <term><option>--version</option></term>
@@ -92,205 +119,83 @@ PostgreSQL documentation
   <title>Interpreting Results</title>
 
   <para>
-   Good results will show most (>90%) individual timing calls take less than
-   one microsecond. Average per loop overhead will be even lower, below 100
-   nanoseconds. This example from an Intel i7-860 system using a TSC clock
-   source shows excellent performance:
-
-<screen><![CDATA[
-Testing timing overhead for 3 seconds.
-Per loop time including overhead: 35.96 ns
-Histogram of timing durations:
-  < us   % of total      count
-     1     96.40465   80435604
-     2      3.59518    2999652
-     4      0.00015        126
-     8      0.00002         13
-    16      0.00000          2
-]]></screen>
+   The first block of output has four columns, with rows showing a
+   shifted-by-one log2(ns) histogram of timing durations (that is, the
+   differences between successive clock readings).  This is not the
+   classic log2(n+1) histogram as it counts zeros separately and then
+   switches to log2(ns) starting from value 1.
   </para>
-
   <para>
-   Note that different units are used for the per loop time than the
-   histogram. The loop can have resolution within a few nanoseconds (ns),
-   while the individual timing calls can only resolve down to one microsecond
-   (us).
+   The columns are:
+   <itemizedlist spacing="compact">
+    <listitem>
+     <simpara>nanosecond value that is &gt;= the durations in this
+     bucket</simpara>
+    </listitem>
+    <listitem>
+     <simpara>percentage of durations in this bucket</simpara>
+    </listitem>
+    <listitem>
+     <simpara>running-sum percentage of durations in this and previous
+     buckets</simpara>
+    </listitem>
+    <listitem>
+     <simpara>count of durations in this bucket</simpara>
+    </listitem>
+   </itemizedlist>
   </para>
-
- </refsect2>
- <refsect2>
-  <title>Measuring Executor Timing Overhead</title>
-
   <para>
-   When the query executor is running a statement using
-   <command>EXPLAIN ANALYZE</command>, individual operations are timed as well
-   as showing a summary.  The overhead of your system can be checked by
-   counting rows with the <application>psql</application> program:
-
-<screen>
-CREATE TABLE t AS SELECT * FROM generate_series(1,100000);
-\timing
-SELECT COUNT(*) FROM t;
-EXPLAIN ANALYZE SELECT COUNT(*) FROM t;
-</screen>
+   The second block of output goes into more detail, showing the exact
+   timing differences observed.  For brevity this list is cut off when the
+   running-sum percentage exceeds the user-selectable cutoff value.
+   However, the largest observed difference is always shown.
   </para>
-
   <para>
-   The i7-860 system measured runs the count query in 9.8 ms while
-   the <command>EXPLAIN ANALYZE</command> version takes 16.6 ms, each
-   processing just over 100,000 rows.  That 6.8 ms difference means the timing
-   overhead per row is 68 ns, about twice what pg_test_timing estimated it
-   would be.  Even that relatively small amount of overhead is making the fully
-   timed count statement take almost 70% longer.  On more substantial queries,
-   the timing overhead would be less problematic.
+   The example results below show that 99.99% of timing loops took between
+   8 and 31 nanoseconds, with the worst case somewhere between 32768 and
+   65535 nanoseconds.  In the second block, we can see that typical loop
+   time is 16 nanoseconds, and the readings appear to have full nanosecond
+   precision.
   </para>
 
- </refsect2>
-
- <refsect2>
-  <title>Changing Time Sources</title>
   <para>
-   On some newer Linux systems, it's possible to change the clock source used
-   to collect timing data at any time.  A second example shows the slowdown
-   possible from switching to the slower acpi_pm time source, on the same
-   system used for the fast results above:
-
 <screen><![CDATA[
-# cat /sys/devices/system/clocksource/clocksource0/available_clocksource
-tsc hpet acpi_pm
-# echo acpi_pm > /sys/devices/system/clocksource/clocksource0/current_clocksource
-# pg_test_timing
-Per loop time including overhead: 722.92 ns
+Testing timing overhead for 3 seconds.
+Average loop time including overhead: 16.40 ns
 Histogram of timing durations:
-  < us   % of total      count
-     1     27.84870    1155682
-     2     72.05956    2990371
-     4      0.07810       3241
-     8      0.01357        563
-    16      0.00007          3
+   <= ns   % of total  running %      count
+       0       0.0000     0.0000          0
+       1       0.0000     0.0000          0
+       3       0.0000     0.0000          0
+       7       0.0000     0.0000          0
+      15       4.5452     4.5452    8313178
+      31      95.4527    99.9979  174581501
+      63       0.0001    99.9981        253
+     127       0.0001    99.9982        165
+     255       0.0000    99.9982         35
+     511       0.0000    99.9982          1
+    1023       0.0013    99.9994       2300
+    2047       0.0004    99.9998        690
+    4095       0.0000    99.9998          9
+    8191       0.0000    99.9998          8
+   16383       0.0002   100.0000        337
+   32767       0.0000   100.0000          2
+   65535       0.0000   100.0000          1
+
+Observed timing durations up to 99.9900%:
+      ns   % of total  running %      count
+      15       4.5452     4.5452    8313178
+      16      58.3785    62.9237  106773354
+      17      33.6840    96.6078   61607584
+      18       3.1151    99.7229    5697480
+      19       0.2638    99.9867     482570
+      20       0.0093    99.9960      17054
+...
+   38051       0.0000   100.0000          1
 ]]></screen>
   </para>
 
-  <para>
-   In this configuration, the sample <command>EXPLAIN ANALYZE</command> above
-   takes 115.9 ms.  That's 1061 ns of timing overhead, again a small multiple
-   of what's measured directly by this utility.  That much timing overhead
-   means the actual query itself is only taking a tiny fraction of the
-   accounted for time, most of it is being consumed in overhead instead.  In
-   this configuration, any <command>EXPLAIN ANALYZE</command> totals involving
-   many timed operations would be inflated significantly by timing overhead.
-  </para>
-
-  <para>
-   FreeBSD also allows changing the time source on the fly, and it logs
-   information about the timer selected during boot:
-
-<screen>
-# dmesg | grep "Timecounter"
-Timecounter "ACPI-fast" frequency 3579545 Hz quality 900
-Timecounter "i8254" frequency 1193182 Hz quality 0
-Timecounters tick every 10.000 msec
-Timecounter "TSC" frequency 2531787134 Hz quality 800
-# sysctl kern.timecounter.hardware=TSC
-kern.timecounter.hardware: ACPI-fast -> TSC
-</screen>
-  </para>
-
-  <para>
-   Other systems may only allow setting the time source on boot.  On older
-   Linux systems the "clock" kernel setting is the only way to make this sort
-   of change.  And even on some more recent ones, the only option you'll see
-   for a clock source is "jiffies".  Jiffies are the older Linux software clock
-   implementation, which can have good resolution when it's backed by fast
-   enough timing hardware, as in this example:
-
-<screen><![CDATA[
-$ cat /sys/devices/system/clocksource/clocksource0/available_clocksource
-jiffies
-$ dmesg | grep time.c
-time.c: Using 3.579545 MHz WALL PM GTOD PIT/TSC timer.
-time.c: Detected 2400.153 MHz processor.
-$ pg_test_timing
-Testing timing overhead for 3 seconds.
-Per timing duration including loop overhead: 97.75 ns
-Histogram of timing durations:
-  < us   % of total      count
-     1     90.23734   27694571
-     2      9.75277    2993204
-     4      0.00981       3010
-     8      0.00007         22
-    16      0.00000          1
-    32      0.00000          1
-]]></screen></para>
-
  </refsect2>
-
- <refsect2>
-  <title>Clock Hardware and Timing Accuracy</title>
-
-  <para>
-   Collecting accurate timing information is normally done on computers using
-   hardware clocks with various levels of accuracy.  With some hardware the
-   operating systems can pass the system clock time almost directly to
-   programs.  A system clock can also be derived from a chip that simply
-   provides timing interrupts, periodic ticks at some known time interval.  In
-   either case, operating system kernels provide a clock source that hides
-   these details.  But the accuracy of that clock source and how quickly it can
-   return results varies based on the underlying hardware.
-  </para>
-
-  <para>
-   Inaccurate time keeping can result in system instability.  Test any change
-   to the clock source very carefully.  Operating system defaults are sometimes
-   made to favor reliability over best accuracy. And if you are using a virtual
-   machine, look into the recommended time sources compatible with it.  Virtual
-   hardware faces additional difficulties when emulating timers, and there are
-   often per operating system settings suggested by vendors.
-  </para>
-
-  <para>
-   The Time Stamp Counter (TSC) clock source is the most accurate one available
-   on current generation CPUs. It's the preferred way to track the system time
-   when it's supported by the operating system and the TSC clock is
-   reliable. There are several ways that TSC can fail to provide an accurate
-   timing source, making it unreliable. Older systems can have a TSC clock that
-   varies based on the CPU temperature, making it unusable for timing. Trying
-   to use TSC on some older multicore CPUs can give a reported time that's
-   inconsistent among multiple cores. This can result in the time going
-   backwards, a problem this program checks for.  And even the newest systems
-   can fail to provide accurate TSC timing with very aggressive power saving
-   configurations.
-  </para>
-
-  <para>
-   Newer operating systems may check for the known TSC problems and switch to a
-   slower, more stable clock source when they are seen.  If your system
-   supports TSC time but doesn't default to that, it may be disabled for a good
-   reason.  And some operating systems may not detect all the possible problems
-   correctly, or will allow using TSC even in situations where it's known to be
-   inaccurate.
-  </para>
-
-  <para>
-   The High Precision Event Timer (HPET) is the preferred timer on systems
-   where it's available and TSC is not accurate.  The timer chip itself is
-   programmable to allow up to 100 nanosecond resolution, but you may not see
-   that much accuracy in your system clock.
-  </para>
-
-  <para>
-   Advanced Configuration and Power Interface (ACPI) provides a Power
-   Management (PM) Timer, which Linux refers to as the acpi_pm.  The clock
-   derived from acpi_pm will at best provide 300 nanosecond resolution.
-  </para>
-
-  <para>
-   Timers used on older PC hardware include the 8254 Programmable Interval
-   Timer (PIT), the real-time clock (RTC), the Advanced Programmable Interrupt
-   Controller (APIC) timer, and the Cyclone timer.  These timers aim for
-   millisecond resolution.
-  </para>
-  </refsect2>
  </refsect1>
 
  <refsect1>
@@ -298,6 +203,8 @@ Histogram of timing durations:
 
   <simplelist type="inline">
    <member><xref linkend="sql-explain"/></member>
+   <member><ulink url="https://wiki.postgresql.org/wiki/Pg_test_timing">Wiki
+   discussion about timing</ulink></member>
   </simplelist>
  </refsect1>
 </refentry>
diff --git a/doc/src/sgml/ref/pgupgrade.sgml b/doc/src/sgml/ref/pgupgrade.sgml
index aeeed297437e6..5ddf3a8ae9257 100644
--- a/doc/src/sgml/ref/pgupgrade.sgml
+++ b/doc/src/sgml/ref/pgupgrade.sgml
@@ -1110,7 +1110,8 @@ psql --username=postgres --file=script.sql postgres
     <member><type>regproc</type></member>
     <member><type>regprocedure</type></member>
    </simplelist>
-   (<type>regclass</type>, <type>regrole</type>, and <type>regtype</type> can be upgraded.)
+   (<type>regclass</type>, <type>regdatabase</type>, <type>regrole</type>, and
+   <type>regtype</type> can be upgraded.)
   </para>
 
   <para>
diff --git a/doc/src/sgml/ref/psql-ref.sgml b/doc/src/sgml/ref/psql-ref.sgml
index 95f4cac2467e3..4f7b11175c671 100644
--- a/doc/src/sgml/ref/psql-ref.sgml
+++ b/doc/src/sgml/ref/psql-ref.sgml
@@ -4623,6 +4623,15 @@ bar
         </listitem>
       </varlistentry>
 
+      <varlistentry id="app-psql-variables-servicefile">
+        <term><varname>SERVICEFILE</varname></term>
+        <listitem>
+        <para>
+        The service file name, if applicable.
+        </para>
+        </listitem>
+      </varlistentry>
+
       <varlistentry id="app-psql-variables-shell-error">
        <term><varname>SHELL_ERROR</varname></term>
        <listitem>
diff --git a/doc/src/sgml/ref/vacuumdb.sgml b/doc/src/sgml/ref/vacuumdb.sgml
index b0680a61814cc..c7d9dca17b867 100644
--- a/doc/src/sgml/ref/vacuumdb.sgml
+++ b/doc/src/sgml/ref/vacuumdb.sgml
@@ -282,9 +282,11 @@ PostgreSQL documentation
       <listitem>
        <para>
         Only analyze relations that are missing statistics for a column, index
-        expression, or extended statistics object.  This option prevents
-        <application>vacuumdb</application> from deleting existing statistics
-        so that the query optimizer's choices do not become transiently worse.
+        expression, or extended statistics object.  When used with
+        <option>--analyze-in-stages</option>, this option prevents
+        <application>vacuumdb</application> from temporarily replacing existing
+        statistics with ones generated with lower statistics targets, thus
+        avoiding transiently worse query optimizer choices.
        </para>
        <para>
         This option can only be used in conjunction with
diff --git a/doc/src/sgml/regress.sgml b/doc/src/sgml/regress.sgml
index bf4ffb3057636..8838fe7f0225f 100644
--- a/doc/src/sgml/regress.sgml
+++ b/doc/src/sgml/regress.sgml
@@ -285,75 +285,88 @@ make check-world PG_TEST_EXTRA='kerberos ldap ssl load_balance libpq_encryption'
     </varlistentry>
 
     <varlistentry>
-     <term><literal>sepgsql</literal></term>
+     <term><literal>libpq_encryption</literal></term>
      <listitem>
       <para>
-       Runs the test suite under <filename>contrib/sepgsql</filename>.  This
-       requires an SELinux environment that is set up in a specific way; see
-       <xref linkend="sepgsql-regression"/>.
+       Runs the test <filename>src/interfaces/libpq/t/005_negotiate_encryption.pl</filename>.
+       This opens TCP/IP listen sockets. If <varname>PG_TEST_EXTRA</varname>
+       also includes <literal>kerberos</literal>, additional tests that require
+       an MIT Kerberos installation are enabled.
       </para>
      </listitem>
     </varlistentry>
 
     <varlistentry>
-     <term><literal>ssl</literal></term>
+     <term><literal>load_balance</literal></term>
      <listitem>
       <para>
-       Runs the test suite under <filename>src/test/ssl</filename>.  This opens TCP/IP listen sockets.
+       Runs the test <filename>src/interfaces/libpq/t/004_load_balance_dns.pl</filename>.
+       This requires editing the system <filename>hosts</filename> file and
+       opens TCP/IP listen sockets.
       </para>
      </listitem>
     </varlistentry>
 
     <varlistentry>
-     <term><literal>load_balance</literal></term>
+     <term><literal>oauth</literal></term>
      <listitem>
       <para>
-       Runs the test <filename>src/interfaces/libpq/t/004_load_balance_dns.pl</filename>.
-       This requires editing the system <filename>hosts</filename> file and
-       opens TCP/IP listen sockets.
+       Runs the test suite under <filename>src/test/modules/oauth_validator</filename>.
+       This opens TCP/IP listen sockets for a test server running HTTPS.
       </para>
      </listitem>
     </varlistentry>
 
     <varlistentry>
-     <term><literal>libpq_encryption</literal></term>
+     <term><literal>regress_dump_restore</literal></term>
      <listitem>
       <para>
-       Runs the test <filename>src/interfaces/libpq/t/005_negotiate_encryption.pl</filename>.
-       This opens TCP/IP listen sockets. If <varname>PG_TEST_EXTRA</varname>
-       also includes <literal>kerberos</literal>, additional tests that require
-       an MIT Kerberos installation are enabled.
+       Runs an additional test suite in
+       <filename>src/bin/pg_upgrade/t/002_pg_upgrade.pl</filename> which
+       cycles the regression database through <command>pg_dump</command>/
+       <command>pg_restore</command>.  Not enabled by default because it
+       is resource intensive.
       </para>
      </listitem>
     </varlistentry>
 
     <varlistentry>
-     <term><literal>wal_consistency_checking</literal></term>
+     <term><literal>sepgsql</literal></term>
      <listitem>
       <para>
-       Uses <literal>wal_consistency_checking=all</literal> while running
-       certain tests under <filename>src/test/recovery</filename>.  Not
-       enabled by default because it is resource intensive.
+       Runs the test suite under <filename>contrib/sepgsql</filename>.  This
+       requires an SELinux environment that is set up in a specific way; see
+       <xref linkend="sepgsql-regression"/>.
       </para>
      </listitem>
     </varlistentry>
 
     <varlistentry>
-     <term><literal>xid_wraparound</literal></term>
+     <term><literal>ssl</literal></term>
      <listitem>
       <para>
-       Runs the test suite under <filename>src/test/modules/xid_wraparound</filename>.
-       Not enabled by default because it is resource intensive.
+       Runs the test suite under <filename>src/test/ssl</filename>.  This opens TCP/IP listen sockets.
       </para>
      </listitem>
     </varlistentry>
 
     <varlistentry>
-     <term><literal>oauth</literal></term>
+     <term><literal>wal_consistency_checking</literal></term>
      <listitem>
       <para>
-       Runs the test suite under <filename>src/test/modules/oauth_validator</filename>.
-       This opens TCP/IP listen sockets for a test server running HTTPS.
+       Uses <literal>wal_consistency_checking=all</literal> while running
+       certain tests under <filename>src/test/recovery</filename>.  Not
+       enabled by default because it is resource intensive.
+      </para>
+     </listitem>
+    </varlistentry>
+
+    <varlistentry>
+     <term><literal>xid_wraparound</literal></term>
+     <listitem>
+      <para>
+       Runs the test suite under <filename>src/test/modules/xid_wraparound</filename>.
+       Not enabled by default because it is resource intensive.
       </para>
      </listitem>
     </varlistentry>
diff --git a/doc/src/sgml/sepgsql.sgml b/doc/src/sgml/sepgsql.sgml
index 03ed7d1c90d15..0708e48bcd950 100644
--- a/doc/src/sgml/sepgsql.sgml
+++ b/doc/src/sgml/sepgsql.sgml
@@ -442,7 +442,7 @@ UPDATE t1 SET x = 2, y = func1(y) WHERE z = 100;
    <para>
     The default database privilege system allows database superusers to
     modify system catalogs using DML commands, and reference or modify
-    toast tables.  These operations are prohibited when
+    TOAST tables.  These operations are prohibited when
     <filename>sepgsql</filename> is enabled.
    </para>
   </sect3>
diff --git a/doc/src/sgml/system-views.sgml b/doc/src/sgml/system-views.sgml
index 986ae1f543dbd..4187191ea7413 100644
--- a/doc/src/sgml/system-views.sgml
+++ b/doc/src/sgml/system-views.sgml
@@ -81,6 +81,11 @@
       <entry>open cursors</entry>
      </row>
 
+     <row>
+      <entry><link linkend="view-pg-dsm-registry-allocations"><structname>pg_dsm_registry_allocations</structname></link></entry>
+      <entry>shared memory allocations tracked in the DSM registry</entry>
+     </row>
+
      <row>
       <entry><link linkend="view-pg-file-settings"><structname>pg_file_settings</structname></link></entry>
       <entry>summary of configuration file contents</entry>
@@ -1086,6 +1091,75 @@ AND c1.path[c2.level] = c2.path[c2.level];
 
  </sect1>
 
+ <sect1 id="view-pg-dsm-registry-allocations">
+  <title><structname>pg_dsm_registry_allocations</structname></title>
+
+  <indexterm zone="view-pg-dsm-registry-allocations">
+   <primary>pg_dsm_registry_allocations</primary>
+  </indexterm>
+
+  <para>
+   The <structname>pg_dsm_registry_allocations</structname> view shows shared
+   memory allocations tracked in the dynamic shared memory (DSM) registry.
+   This includes memory allocated by extensions using the mechanisms detailed
+   in <xref linkend="xfunc-shared-addin-after-startup" />.
+  </para>
+
+  <table>
+   <title><structname>pg_dsm_registry_allocations</structname> Columns</title>
+   <tgroup cols="1">
+    <thead>
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       Column Type
+      </para>
+      <para>
+       Description
+      </para></entry>
+     </row>
+    </thead>
+
+    <tbody>
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>name</structfield> <type>text</type>
+      </para>
+      <para>
+       The name of the allocation in the DSM registry.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>type</structfield> <type>text</type>
+      </para>
+      <para>
+       The type of allocation.  Possible values are <literal>segment</literal>,
+       <literal>area</literal>, and <literal>hash</literal>, which correspond
+       to dynamic shared memory segments, areas, and hash tables, respectively.
+      </para></entry>
+     </row>
+
+     <row>
+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>size</structfield> <type>int8</type>
+      </para>
+      <para>
+       Size of the allocation in bytes.  NULL for entries of type
+       <literal>area</literal> and <literal>hash</literal>.
+      </para></entry>
+     </row>
+    </tbody>
+   </tgroup>
+  </table>
+
+  <para>
+   By default, the <structname>pg_dsm_registry_allocations</structname> view
+   can be read only by superusers or roles with privileges of the
+   <literal>pg_read_all_stats</literal> role.
+  </para>
+ </sect1>
+
  <sect1 id="view-pg-file-settings">
   <title><structname>pg_file_settings</structname></title>
 
@@ -2819,21 +2893,18 @@ SELECT * FROM pg_locks pl LEFT JOIN pg_prepared_xacts ppx
          <para>
           <literal>unreserved</literal> means that the slot no longer
           retains the required WAL files and some of them are to be removed at
-          the next checkpoint.  This state can return
+          the next checkpoint.  This typically occurs when
+          <xref linkend="guc-max-slot-wal-keep-size"/> is set to
+          a non-negative value.  This state can return
           to <literal>reserved</literal> or <literal>extended</literal>.
          </para>
         </listitem>
         <listitem>
          <para>
-          <literal>lost</literal> means that some required WAL files have
-          been removed and this slot is no longer usable.
+          <literal>lost</literal> means that this slot is no longer usable.
          </para>
         </listitem>
        </itemizedlist>
-       The last two states are seen only when
-       <xref linkend="guc-max-slot-wal-keep-size"/> is
-       non-negative. If <structfield>restart_lsn</structfield> is NULL, this
-       field is null.
       </para></entry>
      </row>
 
@@ -2932,7 +3003,7 @@ SELECT * FROM pg_locks pl LEFT JOIN pg_prepared_xacts ppx
         <listitem>
          <para>
           <literal>idle_timeout</literal> means that the slot has remained
-          idle longer than the configured
+          inactive longer than the configured
           <xref linkend="guc-idle-replication-slot-timeout"/> duration.
          </para>
         </listitem>
diff --git a/doc/src/sgml/test-decoding.sgml b/doc/src/sgml/test-decoding.sgml
index 5d1ae8f4f52e2..7d3d590471a32 100644
--- a/doc/src/sgml/test-decoding.sgml
+++ b/doc/src/sgml/test-decoding.sgml
@@ -25,16 +25,16 @@
 
 <programlisting>
 postgres=# SELECT * FROM pg_logical_slot_get_changes('test_slot', NULL, NULL, 'include-xids', '0');
-   lsn     | xid |                       data
------------+-----+--------------------------------------------------
- 0/16D30F8 | 691 | BEGIN
- 0/16D32A0 | 691 | table public.data: INSERT: id[int4]:2 data[text]:'arg'
- 0/16D32A0 | 691 | table public.data: INSERT: id[int4]:3 data[text]:'demo'
- 0/16D32A0 | 691 | COMMIT
- 0/16D32D8 | 692 | BEGIN
- 0/16D3398 | 692 | table public.data: DELETE: id[int4]:2
- 0/16D3398 | 692 | table public.data: DELETE: id[int4]:3
- 0/16D3398 | 692 | COMMIT
+    lsn     | xid |                       data
+------------+-----+--------------------------------------------------
+ 0/016D30F8 | 691 | BEGIN
+ 0/016D32A0 | 691 | table public.data: INSERT: id[int4]:2 data[text]:'arg'
+ 0/016D32A0 | 691 | table public.data: INSERT: id[int4]:3 data[text]:'demo'
+ 0/016D32A0 | 691 | COMMIT
+ 0/016D32D8 | 692 | BEGIN
+ 0/016D3398 | 692 | table public.data: DELETE: id[int4]:2
+ 0/016D3398 | 692 | table public.data: DELETE: id[int4]:3
+ 0/016D3398 | 692 | COMMIT
 (8 rows)
 </programlisting>
  </para>
@@ -45,18 +45,18 @@ postgres=# SELECT * FROM pg_logical_slot_get_changes('test_slot', NULL, NULL, 'i
 
 <programlisting>
 postgres[33712]=#* SELECT * FROM pg_logical_slot_get_changes('test_slot', NULL, NULL, 'stream-changes', '1');
-    lsn    | xid |                       data
------------+-----+--------------------------------------------------
- 0/16B21F8 | 503 | opening a streamed block for transaction TXN 503
- 0/16B21F8 | 503 | streaming change for TXN 503
- 0/16B2300 | 503 | streaming change for TXN 503
- 0/16B2408 | 503 | streaming change for TXN 503
- 0/16BEBA0 | 503 | closing a streamed block for transaction TXN 503
- 0/16B21F8 | 503 | opening a streamed block for transaction TXN 503
- 0/16BECA8 | 503 | streaming change for TXN 503
- 0/16BEDB0 | 503 | streaming change for TXN 503
- 0/16BEEB8 | 503 | streaming change for TXN 503
- 0/16BEBA0 | 503 | closing a streamed block for transaction TXN 503
+    lsn     | xid |                       data
+------------+-----+--------------------------------------------------
+ 0/016B21F8 | 503 | opening a streamed block for transaction TXN 503
+ 0/016B21F8 | 503 | streaming change for TXN 503
+ 0/016B2300 | 503 | streaming change for TXN 503
+ 0/016B2408 | 503 | streaming change for TXN 503
+ 0/016BEBA0 | 503 | closing a streamed block for transaction TXN 503
+ 0/016B21F8 | 503 | opening a streamed block for transaction TXN 503
+ 0/016BECA8 | 503 | streaming change for TXN 503
+ 0/016BEDB0 | 503 | streaming change for TXN 503
+ 0/016BEEB8 | 503 | streaming change for TXN 503
+ 0/016BEBA0 | 503 | closing a streamed block for transaction TXN 503
 (10 rows)
 </programlisting>
  </para>
diff --git a/doc/src/sgml/xfunc.sgml b/doc/src/sgml/xfunc.sgml
index 2d81afce8cb9b..30219f432d970 100644
--- a/doc/src/sgml/xfunc.sgml
+++ b/doc/src/sgml/xfunc.sgml
@@ -2165,7 +2165,7 @@ memcpy(destination->data, buffer, 40);
      it's considered good style to use the macro <literal>VARHDRSZ</literal>
      to refer to the size of the overhead for a variable-length type.
      Also, the length field <emphasis>must</emphasis> be set using the
-     <literal>SET_VARSIZE</literal> macro, not by simple assignment.
+     <literal>SET_VARSIZE</literal> function, not by simple assignment.
     </para>
 
     <para>
diff --git a/doc/src/sgml/xoper.sgml b/doc/src/sgml/xoper.sgml
index 954a90d77d0ed..853b07a9f1489 100644
--- a/doc/src/sgml/xoper.sgml
+++ b/doc/src/sgml/xoper.sgml
@@ -21,7 +21,7 @@
 
   <para>
    <productname>PostgreSQL</productname> supports prefix
-   and infix operators.  Operators can be
+   and binary (or infix) operators.  Operators can be
    overloaded;<indexterm><primary>overloading</primary><secondary>operators</secondary></indexterm>
    that is, the same operator name can be used for different operators
    that have different numbers and types of operands.  When a query is
diff --git a/meson.build b/meson.build
index 36e168a1a2ace..ca423dc8e12f3 100644
--- a/meson.build
+++ b/meson.build
@@ -11,10 +11,11 @@ project('postgresql',
   version: '19devel',
   license: 'PostgreSQL',
 
-  # We want < 0.56 for python 3.5 compatibility on old platforms. EPEL for
-  # RHEL 7 has 0.55. < 0.54 would require replacing some uses of the fs
-  # module, < 0.53 all uses of fs. So far there's no need to go to >=0.56.
-  meson_version: '>=0.54',
+  # We want < 0.62 for python 3.6 compatibility on old platforms.
+  # RHEL 8 has 0.58.  < 0.57 would require various additional
+  # backward-compatibility conditionals.
+  # Meson 0.57.0 and 0.57.1 are buggy, therefore >=0.57.2.
+  meson_version: '>=0.57.2',
   default_options: [
     'warning_level=1', #-Wall equivalent
     'b_pch=false',
@@ -279,6 +280,10 @@ elif host_system == 'windows'
     # define before including <time.h> for getting localtime_r() etc. on MinGW
     cppflags += '-D_POSIX_C_SOURCE'
   endif
+  if cc.get_id() == 'msvc'
+    # required for VA_ARGS_NARGS() in c.h; requires VS 2019
+    cppflags += '/Zc:preprocessor'
+  endif
 
   export_file_format = 'win'
   export_file_suffix = 'def'
@@ -943,10 +948,10 @@ if not libcurlopt.disabled()
   # libcurl and one of either epoll or kqueue.
   oauth_flow_supported = (
     libcurl.found()
-    and (cc.check_header('sys/event.h', required: false,
-                         args: test_c_args, include_directories: postgres_inc)
-         or cc.check_header('sys/epoll.h', required: false,
-                            args: test_c_args, include_directories: postgres_inc))
+    and (cc.has_header('sys/event.h',
+                       args: test_c_args, include_directories: postgres_inc)
+         or cc.has_header('sys/epoll.h',
+                          args: test_c_args, include_directories: postgres_inc))
   )
 
   if oauth_flow_supported
@@ -990,6 +995,12 @@ liburingopt = get_option('liburing')
 liburing = dependency('liburing', required: liburingopt)
 if liburing.found()
   cdata.set('USE_LIBURING', 1)
+
+  if cc.has_function('io_uring_queue_init_mem',
+      dependencies: liburing, args: test_c_args)
+    cdata.set('HAVE_LIBURING_QUEUE_INIT_MEM', 1)
+  endif
+
 endif
 
 
@@ -1284,7 +1295,7 @@ pyopt = get_option('plpython')
 python3_dep = not_found_dep
 if not pyopt.disabled()
   pm = import('python')
-  python3_inst = pm.find_installation(python.path(), required: pyopt)
+  python3_inst = pm.find_installation(python.full_path(), required: pyopt)
   if python3_inst.found()
     python3_dep = python3_inst.dependency(embed: true, required: pyopt)
     # Remove this check after we depend on Meson >= 1.1.0
@@ -1985,10 +1996,7 @@ if cc.links('''
   cdata.set('HAVE__BUILTIN_OP_OVERFLOW', 1)
 endif
 
-
-# XXX: The configure.ac check for __cpuid() is broken, we don't copy that
-# here. To prevent problems due to two detection methods working, stop
-# checking after one.
+# Check for __get_cpuid() and __cpuid().
 if cc.links('''
     #include <cpuid.h>
     int main(int arg, char **argv)
@@ -3146,13 +3154,13 @@ gen_kwlist_cmd = [
 ###
 
 if host_system == 'windows'
-  pg_ico = meson.source_root() / 'src' / 'port' / 'win32.ico'
+  pg_ico = meson.project_source_root() / 'src' / 'port' / 'win32.ico'
   win32ver_rc = files('src/port/win32ver.rc')
   rcgen = find_program('src/tools/rcgen', native: true)
 
   rcgen_base_args = [
     '--srcdir', '@SOURCE_DIR@',
-    '--builddir', meson.build_root(),
+    '--builddir', meson.project_build_root(),
     '--rcout', '@OUTPUT0@',
     '--out', '@OUTPUT1@',
     '--input', '@INPUT@',
@@ -3161,11 +3169,11 @@ if host_system == 'windows'
 
   if cc.get_argument_syntax() == 'msvc'
     rc = find_program('rc', required: true)
-    rcgen_base_args += ['--rc', rc.path()]
+    rcgen_base_args += ['--rc', rc.full_path()]
     rcgen_outputs = ['@BASENAME@.rc', '@BASENAME@.res']
   else
     windres = find_program('windres', required: true)
-    rcgen_base_args += ['--windres', windres.path()]
+    rcgen_base_args += ['--windres', windres.full_path()]
     rcgen_outputs = ['@BASENAME@.rc', '@BASENAME@.obj']
   endif
 
@@ -3398,7 +3406,7 @@ foreach t1 : configure_files
   potentially_conflicting_files += meson.current_build_dir() / t
 endforeach
 foreach sub, fnames : generated_sources_ac
-  sub = meson.build_root() / sub
+  sub = meson.project_build_root() / sub
   foreach fname : fnames
     potentially_conflicting_files += sub / fname
   endforeach
@@ -3498,7 +3506,7 @@ run_target('install-test-files',
 ###############################################################
 
 # DESTDIR for the installation we'll run tests in
-test_install_destdir = meson.build_root() / 'tmp_install/'
+test_install_destdir = meson.project_build_root() / 'tmp_install/'
 
 # DESTDIR + prefix appropriately munged
 if build_system != 'windows'
@@ -3541,7 +3549,7 @@ test('install_test_files',
     is_parallel: false,
     suite: ['setup'])
 
-test_result_dir = meson.build_root() / 'testrun'
+test_result_dir = meson.project_build_root() / 'testrun'
 
 
 # XXX: pg_regress doesn't assign unique ports on windows. To avoid the
@@ -3552,12 +3560,12 @@ testport = 40000
 
 test_env = environment()
 
-test_initdb_template = meson.build_root() / 'tmp_install' / 'initdb-template'
+test_initdb_template = meson.project_build_root() / 'tmp_install' / 'initdb-template'
 test_env.set('PG_REGRESS', pg_regress.full_path())
 test_env.set('REGRESS_SHLIB', regress_module.full_path())
 test_env.set('INITDB_TEMPLATE', test_initdb_template)
 # for Cluster.pm's portlock logic
-test_env.set('top_builddir', meson.build_root())
+test_env.set('top_builddir', meson.project_build_root())
 
 # Add the temporary installation to the library search path on platforms where
 # that works (everything but windows, basically). On windows everything
@@ -3601,26 +3609,20 @@ sys.exit(sp.returncode)
 # Test Generation
 ###############################################################
 
-# When using a meson version understanding exclude_suites, define a
-# 'tmp_install' test setup (the default) that excludes tests running against a
-# pre-existing install and a 'running' setup that conflicts with creation of
-# the temporary installation and tap tests (which don't support running
-# against a running server).
+# Define a 'tmp_install' test setup (the default) that excludes tests
+# running against a pre-existing install and a 'running' setup that
+# conflicts with creation of the temporary installation and tap tests
+# (which don't support running against a running server).
 
 running_suites = []
 install_suites = []
-if meson.version().version_compare('>=0.57')
-  runningcheck = true
-else
-  runningcheck = false
-endif
 
 testwrap = files('src/tools/testwrap')
 
 foreach test_dir : tests
   testwrap_base = [
     testwrap,
-    '--basedir', meson.build_root(),
+    '--basedir', meson.project_build_root(),
     '--srcdir', test_dir['sd'],
     # Some test suites are not run by default but can be run if selected by the
     # user via variable PG_TEST_EXTRA. Pass configuration time value of
@@ -3710,7 +3712,7 @@ foreach test_dir : tests
       install_suites += test_group
 
       # some tests can't support running against running DB
-      if runningcheck and t.get('runningcheck', true)
+      if t.get('runningcheck', true)
         test(test_group_running / kind,
           python,
           args: [
@@ -3737,8 +3739,8 @@ foreach test_dir : tests
       endif
 
       test_command = [
-        perl.path(),
-        '-I', meson.source_root() / 'src/test/perl',
+        perl.full_path(),
+        '-I', meson.project_source_root() / 'src/test/perl',
         '-I', test_dir['sd'],
       ]
 
@@ -3793,13 +3795,11 @@ foreach test_dir : tests
 endforeach # directories with tests
 
 # repeat condition so meson realizes version dependency
-if meson.version().version_compare('>=0.57')
-  add_test_setup('tmp_install',
-    is_default: true,
-    exclude_suites: running_suites)
-  add_test_setup('running',
-    exclude_suites: ['setup'] + install_suites)
-endif
+add_test_setup('tmp_install',
+  is_default: true,
+  exclude_suites: running_suites)
+add_test_setup('running',
+  exclude_suites: ['setup'] + install_suites)
 
 
 
@@ -3856,7 +3856,7 @@ tar_gz = custom_target('tar.gz',
             '--format', 'tar.gz',
             '-9',
             '--prefix', distdir + '/',
-            '-o', join_paths(meson.build_root(), '@OUTPUT@'),
+            '-o', join_paths(meson.project_build_root(), '@OUTPUT@'),
             pg_git_revision],
   output: distdir + '.tar.gz',
 )
@@ -3866,11 +3866,11 @@ if bzip2.found()
     build_always_stale: true,
     command: [git, '-C', '@SOURCE_ROOT@',
               '-c', 'core.autocrlf=false',
-              '-c', 'tar.tar.bz2.command="@0@" -c'.format(bzip2.path()),
+              '-c', 'tar.tar.bz2.command="@0@" -c'.format(bzip2.full_path()),
               'archive',
               '--format', 'tar.bz2',
               '--prefix', distdir + '/',
-              '-o', join_paths(meson.build_root(), '@OUTPUT@'),
+              '-o', join_paths(meson.project_build_root(), '@OUTPUT@'),
               pg_git_revision],
     output: distdir + '.tar.bz2',
   )
@@ -3887,10 +3887,7 @@ alias_target('pgdist', [tar_gz, tar_bz2])
 # But not if we are in a subproject, in case the parent project wants to
 # create a dist using the standard Meson command.
 if not meson.is_subproject()
-  # We can only pass the identifier perl here when we depend on >= 0.55
-  if meson.version().version_compare('>=0.55')
-    meson.add_dist_script(perl, '-e', 'exit 1')
-  endif
+  meson.add_dist_script(perl, '-e', 'exit 1')
 endif
 
 
@@ -3899,106 +3896,102 @@ endif
 # The End, The End, My Friend
 ###############################################################
 
-if meson.version().version_compare('>=0.57')
+summary(
+  {
+    'data block size': '@0@ kB'.format(cdata.get('BLCKSZ') / 1024),
+    'WAL block size': '@0@ kB'.format(cdata.get('XLOG_BLCKSZ') / 1024),
+    'segment size': get_option('segsize_blocks') != 0 ?
+      '@0@ blocks'.format(cdata.get('RELSEG_SIZE')) :
+      '@0@ GB'.format(get_option('segsize')),
+  },
+  section: 'Data layout',
+)
 
-  summary(
-    {
-      'data block size': '@0@ kB'.format(cdata.get('BLCKSZ') / 1024),
-      'WAL block size': '@0@ kB'.format(cdata.get('XLOG_BLCKSZ') / 1024),
-      'segment size': get_option('segsize_blocks') != 0 ?
-        '@0@ blocks'.format(cdata.get('RELSEG_SIZE')) :
-        '@0@ GB'.format(get_option('segsize')),
-    },
-    section: 'Data layout',
-  )
+summary(
+  {
+    'host system': '@0@ @1@'.format(host_system, host_cpu),
+    'build system': '@0@ @1@'.format(build_machine.system(),
+                                     build_machine.cpu_family()),
+  },
+  section: 'System',
+)
 
-  summary(
-    {
-      'host system': '@0@ @1@'.format(host_system, host_cpu),
-      'build system': '@0@ @1@'.format(build_machine.system(),
-                                       build_machine.cpu_family()),
-    },
-    section: 'System',
-  )
+summary(
+  {
+    'linker': '@0@'.format(cc.get_linker_id()),
+    'C compiler': '@0@ @1@'.format(cc.get_id(), cc.version()),
+  },
+  section: 'Compiler',
+)
 
+summary(
+  {
+    'CPP FLAGS': ' '.join(cppflags),
+    'C FLAGS, functional': ' '.join(cflags),
+    'C FLAGS, warnings': ' '.join(cflags_warn),
+    'C FLAGS, modules': ' '.join(cflags_mod),
+    'C FLAGS, user specified': ' '.join(get_option('c_args')),
+    'LD FLAGS': ' '.join(ldflags + get_option('c_link_args')),
+  },
+  section: 'Compiler Flags',
+)
+
+if llvm.found()
   summary(
     {
-      'linker': '@0@'.format(cc.get_linker_id()),
-      'C compiler': '@0@ @1@'.format(cc.get_id(), cc.version()),
+      'C++ compiler': '@0@ @1@'.format(cpp.get_id(), cpp.version()),
     },
     section: 'Compiler',
   )
 
   summary(
     {
-      'CPP FLAGS': ' '.join(cppflags),
-      'C FLAGS, functional': ' '.join(cflags),
-      'C FLAGS, warnings': ' '.join(cflags_warn),
-      'C FLAGS, modules': ' '.join(cflags_mod),
-      'C FLAGS, user specified': ' '.join(get_option('c_args')),
-      'LD FLAGS': ' '.join(ldflags + get_option('c_link_args')),
+      'C++ FLAGS, functional': ' '.join(cxxflags),
+      'C++ FLAGS, warnings': ' '.join(cxxflags_warn),
+      'C++ FLAGS, user specified': ' '.join(get_option('cpp_args')),
     },
     section: 'Compiler Flags',
   )
+endif
 
-  if llvm.found()
-    summary(
-      {
-        'C++ compiler': '@0@ @1@'.format(cpp.get_id(), cpp.version()),
-      },
-      section: 'Compiler',
-    )
-
-    summary(
-      {
-        'C++ FLAGS, functional': ' '.join(cxxflags),
-        'C++ FLAGS, warnings': ' '.join(cxxflags_warn),
-        'C++ FLAGS, user specified': ' '.join(get_option('cpp_args')),
-      },
-      section: 'Compiler Flags',
-    )
-  endif
-
-  summary(
-    {
-      'bison': '@0@ @1@'.format(bison.full_path(), bison_version),
-      'dtrace': dtrace,
-      'flex': '@0@ @1@'.format(flex.full_path(), flex_version),
-    },
-    section: 'Programs',
-  )
-
-  summary(
-    {
-      'bonjour': bonjour,
-      'bsd_auth': bsd_auth,
-      'docs': docs_dep,
-      'docs_pdf': docs_pdf_dep,
-      'gss': gssapi,
-      'icu': icu,
-      'ldap': ldap,
-      'libcurl': libcurl,
-      'libnuma': libnuma,
-      'liburing': liburing,
-      'libxml': libxml,
-      'libxslt': libxslt,
-      'llvm': llvm,
-      'lz4': lz4,
-      'nls': libintl,
-      'openssl': ssl,
-      'pam': pam,
-      'plperl': [perl_dep, perlversion],
-      'plpython': python3_dep,
-      'pltcl': tcl_dep,
-      'readline': readline,
-      'selinux': selinux,
-      'systemd': systemd,
-      'uuid': uuid,
-      'zlib': zlib,
-      'zstd': zstd,
-    },
-    section: 'External libraries',
-    list_sep: ' ',
-  )
+summary(
+  {
+    'bison': '@0@ @1@'.format(bison.full_path(), bison_version),
+    'dtrace': dtrace,
+    'flex': '@0@ @1@'.format(flex.full_path(), flex_version),
+  },
+  section: 'Programs',
+)
 
-endif
+summary(
+  {
+    'bonjour': bonjour,
+    'bsd_auth': bsd_auth,
+    'docs': docs_dep,
+    'docs_pdf': docs_pdf_dep,
+    'gss': gssapi,
+    'icu': icu,
+    'ldap': ldap,
+    'libcurl': libcurl,
+    'libnuma': libnuma,
+    'liburing': liburing,
+    'libxml': libxml,
+    'libxslt': libxslt,
+    'llvm': llvm,
+    'lz4': lz4,
+    'nls': libintl,
+    'openssl': ssl,
+    'pam': pam,
+    'plperl': [perl_dep, perlversion],
+    'plpython': python3_dep,
+    'pltcl': tcl_dep,
+    'readline': readline,
+    'selinux': selinux,
+    'systemd': systemd,
+    'uuid': uuid,
+    'zlib': zlib,
+    'zstd': zstd,
+  },
+  section: 'External libraries',
+  list_sep: ' ',
+)
diff --git a/src/Makefile.global.in b/src/Makefile.global.in
index 04952b533ded9..8b1b357beaa04 100644
--- a/src/Makefile.global.in
+++ b/src/Makefile.global.in
@@ -254,7 +254,7 @@ CPP = @CPP@
 CPPFLAGS = @CPPFLAGS@
 PG_SYSROOT = @PG_SYSROOT@
 
-override CPPFLAGS := $(ICU_CFLAGS) $(LIBNUMA_CFLAGS) $(LIBURING_CFLAGS) $(CPPFLAGS)
+override CPPFLAGS += $(ICU_CFLAGS) $(LIBNUMA_CFLAGS) $(LIBURING_CFLAGS)
 
 ifdef PGXS
 override CPPFLAGS := -I$(includedir_server) -I$(includedir_internal) $(CPPFLAGS)
diff --git a/src/backend/access/brin/brin_minmax_multi.c b/src/backend/access/brin/brin_minmax_multi.c
index 0d1507a2a3624..a5a414182caa6 100644
--- a/src/backend/access/brin/brin_minmax_multi.c
+++ b/src/backend/access/brin/brin_minmax_multi.c
@@ -624,7 +624,7 @@ brin_range_serialize(Ranges *range)
 
 		for (i = 0; i < nvalues; i++)
 		{
-			len += VARSIZE_ANY(range->values[i]);
+			len += VARSIZE_ANY(DatumGetPointer(range->values[i]));
 		}
 	}
 	else if (typlen == -2)		/* cstring */
@@ -2032,7 +2032,7 @@ brin_minmax_multi_distance_numeric(PG_FUNCTION_ARGS)
 
 	d = DirectFunctionCall2(numeric_sub, a2, a1);	/* a2 - a1 */
 
-	PG_RETURN_FLOAT8(DirectFunctionCall1(numeric_float8, d));
+	PG_RETURN_DATUM(DirectFunctionCall1(numeric_float8, d));
 }
 
 /*
diff --git a/src/backend/access/common/heaptuple.c b/src/backend/access/common/heaptuple.c
index 969d1028cae89..a410b5eb99b99 100644
--- a/src/backend/access/common/heaptuple.c
+++ b/src/backend/access/common/heaptuple.c
@@ -189,7 +189,7 @@ getmissingattr(TupleDesc tupleDesc,
 			if (att->attlen > 0)
 				key.len = att->attlen;
 			else
-				key.len = VARSIZE_ANY(attrmiss->am_value);
+				key.len = VARSIZE_ANY(DatumGetPointer(attrmiss->am_value));
 			key.value = attrmiss->am_value;
 
 			entry = hash_search(missing_cache, &key, HASH_ENTER, &found);
@@ -901,9 +901,9 @@ expand_tuple(HeapTuple *targetHeapTuple,
 												  att->attlen,
 												  attrmiss[attnum].am_value);
 
-				targetDataLen = att_addlength_pointer(targetDataLen,
-													  att->attlen,
-													  attrmiss[attnum].am_value);
+				targetDataLen = att_addlength_datum(targetDataLen,
+													att->attlen,
+													attrmiss[attnum].am_value);
 			}
 			else
 			{
diff --git a/src/backend/access/common/printsimple.c b/src/backend/access/common/printsimple.c
index f346ab3e8125b..a09c8fcd3323e 100644
--- a/src/backend/access/common/printsimple.c
+++ b/src/backend/access/common/printsimple.c
@@ -123,7 +123,7 @@ printsimple(TupleTableSlot *slot, DestReceiver *self)
 
 			case OIDOID:
 				{
-					Oid			num = ObjectIdGetDatum(value);
+					Oid			num = DatumGetObjectId(value);
 					char		str[10];	/* 10 digits */
 					int			len;
 
diff --git a/src/backend/access/common/printtup.c b/src/backend/access/common/printtup.c
index 830a3d883aa2e..6d3045e233211 100644
--- a/src/backend/access/common/printtup.c
+++ b/src/backend/access/common/printtup.c
@@ -350,7 +350,7 @@ printtup(TupleTableSlot *slot, DestReceiver *self)
 		 */
 		if (thisState->typisvarlena)
 			VALGRIND_CHECK_MEM_IS_DEFINED(DatumGetPointer(attr),
-										  VARSIZE_ANY(attr));
+										  VARSIZE_ANY(DatumGetPointer(attr)));
 
 		if (thisState->format == 0)
 		{
diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index 50747c1639612..594a657ea1a78 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -1190,8 +1190,8 @@ transformRelOptions(Datum oldOptions, List *defList, const char *namspace,
 
 		for (i = 0; i < noldoptions; i++)
 		{
-			char	   *text_str = VARDATA(oldoptions[i]);
-			int			text_len = VARSIZE(oldoptions[i]) - VARHDRSZ;
+			char	   *text_str = VARDATA(DatumGetPointer(oldoptions[i]));
+			int			text_len = VARSIZE(DatumGetPointer(oldoptions[i])) - VARHDRSZ;
 
 			/* Search for a match in defList */
 			foreach(cell, defList)
@@ -1456,8 +1456,8 @@ parseRelOptionsInternal(Datum options, bool validate,
 
 	for (i = 0; i < noptions; i++)
 	{
-		char	   *text_str = VARDATA(optiondatums[i]);
-		int			text_len = VARSIZE(optiondatums[i]) - VARHDRSZ;
+		char	   *text_str = VARDATA(DatumGetPointer(optiondatums[i]));
+		int			text_len = VARSIZE(DatumGetPointer(optiondatums[i])) - VARHDRSZ;
 		int			j;
 
 		/* Search for a match in reloptions */
diff --git a/src/backend/access/common/toast_compression.c b/src/backend/access/common/toast_compression.c
index 21f2f4af97e3f..926f1e4008abe 100644
--- a/src/backend/access/common/toast_compression.c
+++ b/src/backend/access/common/toast_compression.c
@@ -25,11 +25,11 @@
 /* GUC */
 int			default_toast_compression = TOAST_PGLZ_COMPRESSION;
 
-#define NO_LZ4_SUPPORT() \
+#define NO_COMPRESSION_SUPPORT(method) \
 	ereport(ERROR, \
 			(errcode(ERRCODE_FEATURE_NOT_SUPPORTED), \
-			 errmsg("compression method lz4 not supported"), \
-			 errdetail("This functionality requires the server to be built with lz4 support.")))
+			 errmsg("compression method %s not supported", method), \
+			 errdetail("This functionality requires the server to be built with %s support.", method)))
 
 /*
  * Compress a varlena using PGLZ.
@@ -139,7 +139,7 @@ struct varlena *
 lz4_compress_datum(const struct varlena *value)
 {
 #ifndef USE_LZ4
-	NO_LZ4_SUPPORT();
+	NO_COMPRESSION_SUPPORT("lz4");
 	return NULL;				/* keep compiler quiet */
 #else
 	int32		valsize;
@@ -182,7 +182,7 @@ struct varlena *
 lz4_decompress_datum(const struct varlena *value)
 {
 #ifndef USE_LZ4
-	NO_LZ4_SUPPORT();
+	NO_COMPRESSION_SUPPORT("lz4");
 	return NULL;				/* keep compiler quiet */
 #else
 	int32		rawsize;
@@ -215,7 +215,7 @@ struct varlena *
 lz4_decompress_datum_slice(const struct varlena *value, int32 slicelength)
 {
 #ifndef USE_LZ4
-	NO_LZ4_SUPPORT();
+	NO_COMPRESSION_SUPPORT("lz4");
 	return NULL;				/* keep compiler quiet */
 #else
 	int32		rawsize;
@@ -289,7 +289,7 @@ CompressionNameToMethod(const char *compression)
 	else if (strcmp(compression, "lz4") == 0)
 	{
 #ifndef USE_LZ4
-		NO_LZ4_SUPPORT();
+		NO_COMPRESSION_SUPPORT("lz4");
 #endif
 		return TOAST_LZ4_COMPRESSION;
 	}
diff --git a/src/backend/access/common/toast_internals.c b/src/backend/access/common/toast_internals.c
index 7d8be8346ce52..196e06115e936 100644
--- a/src/backend/access/common/toast_internals.c
+++ b/src/backend/access/common/toast_internals.c
@@ -144,7 +144,7 @@ toast_save_datum(Relation rel, Datum value,
 	int			num_indexes;
 	int			validIndex;
 
-	Assert(!VARATT_IS_EXTERNAL(value));
+	Assert(!VARATT_IS_EXTERNAL(dval));
 
 	/*
 	 * Open the toast relation and its indexes.  We can use the index to check
diff --git a/src/backend/access/common/tupdesc.c b/src/backend/access/common/tupdesc.c
index 020d00cd01ce7..be60005ae4600 100644
--- a/src/backend/access/common/tupdesc.c
+++ b/src/backend/access/common/tupdesc.c
@@ -815,10 +815,10 @@ hashRowType(TupleDesc desc)
 	uint32		s;
 	int			i;
 
-	s = hash_combine(0, hash_uint32(desc->natts));
-	s = hash_combine(s, hash_uint32(desc->tdtypeid));
+	s = hash_combine(0, hash_bytes_uint32(desc->natts));
+	s = hash_combine(s, hash_bytes_uint32(desc->tdtypeid));
 	for (i = 0; i < desc->natts; ++i)
-		s = hash_combine(s, hash_uint32(TupleDescAttr(desc, i)->atttypid));
+		s = hash_combine(s, hash_bytes_uint32(TupleDescAttr(desc, i)->atttypid));
 
 	return s;
 }
diff --git a/src/backend/access/gin/gininsert.c b/src/backend/access/gin/gininsert.c
index a65acd8910493..47b1898a06463 100644
--- a/src/backend/access/gin/gininsert.c
+++ b/src/backend/access/gin/gininsert.c
@@ -2233,7 +2233,7 @@ _gin_build_tuple(OffsetNumber attrnum, unsigned char category,
 	else if (typlen > 0)
 		keylen = typlen;
 	else if (typlen == -1)
-		keylen = VARSIZE_ANY(key);
+		keylen = VARSIZE_ANY(DatumGetPointer(key));
 	else if (typlen == -2)
 		keylen = strlen(DatumGetPointer(key)) + 1;
 	else
diff --git a/src/backend/access/heap/vacuumlazy.c b/src/backend/access/heap/vacuumlazy.c
index 4111a8996b5a1..14036c27e878a 100644
--- a/src/backend/access/heap/vacuumlazy.c
+++ b/src/backend/access/heap/vacuumlazy.c
@@ -423,7 +423,7 @@ typedef struct LVSavedErrInfo
 /* non-export function prototypes */
 static void lazy_scan_heap(LVRelState *vacrel);
 static void heap_vacuum_eager_scan_setup(LVRelState *vacrel,
-										 VacuumParams *params);
+										 const VacuumParams params);
 static BlockNumber heap_vac_scan_next_block(ReadStream *stream,
 											void *callback_private_data,
 											void *per_buffer_data);
@@ -431,7 +431,7 @@ static void find_next_unskippable_block(LVRelState *vacrel, bool *skipsallvis);
 static bool lazy_scan_new_or_empty(LVRelState *vacrel, Buffer buf,
 								   BlockNumber blkno, Page page,
 								   bool sharelock, Buffer vmbuffer);
-static void lazy_scan_prune(LVRelState *vacrel, Buffer buf,
+static int	lazy_scan_prune(LVRelState *vacrel, Buffer buf,
 							BlockNumber blkno, Page page,
 							Buffer vmbuffer, bool all_visible_according_to_vm,
 							bool *has_lpdead_items, bool *vm_page_frozen);
@@ -485,7 +485,7 @@ static void restore_vacuum_error_info(LVRelState *vacrel,
  * vacuum options or for relfrozenxid/relminmxid advancement.
  */
 static void
-heap_vacuum_eager_scan_setup(LVRelState *vacrel, VacuumParams *params)
+heap_vacuum_eager_scan_setup(LVRelState *vacrel, const VacuumParams params)
 {
 	uint32		randseed;
 	BlockNumber allvisible;
@@ -504,7 +504,7 @@ heap_vacuum_eager_scan_setup(LVRelState *vacrel, VacuumParams *params)
 	vacrel->eager_scan_remaining_successes = 0;
 
 	/* If eager scanning is explicitly disabled, just return. */
-	if (params->max_eager_freeze_failure_rate == 0)
+	if (params.max_eager_freeze_failure_rate == 0)
 		return;
 
 	/*
@@ -581,11 +581,11 @@ heap_vacuum_eager_scan_setup(LVRelState *vacrel, VacuumParams *params)
 
 	vacrel->next_eager_scan_region_start = randseed % EAGER_SCAN_REGION_SIZE;
 
-	Assert(params->max_eager_freeze_failure_rate > 0 &&
-		   params->max_eager_freeze_failure_rate <= 1);
+	Assert(params.max_eager_freeze_failure_rate > 0 &&
+		   params.max_eager_freeze_failure_rate <= 1);
 
 	vacrel->eager_scan_max_fails_per_region =
-		params->max_eager_freeze_failure_rate *
+		params.max_eager_freeze_failure_rate *
 		EAGER_SCAN_REGION_SIZE;
 
 	/*
@@ -612,7 +612,7 @@ heap_vacuum_eager_scan_setup(LVRelState *vacrel, VacuumParams *params)
  *		and locked the relation.
  */
 void
-heap_vacuum_rel(Relation rel, VacuumParams *params,
+heap_vacuum_rel(Relation rel, const VacuumParams params,
 				BufferAccessStrategy bstrategy)
 {
 	LVRelState *vacrel;
@@ -634,9 +634,9 @@ heap_vacuum_rel(Relation rel, VacuumParams *params,
 	ErrorContextCallback errcallback;
 	char	  **indnames = NULL;
 
-	verbose = (params->options & VACOPT_VERBOSE) != 0;
+	verbose = (params.options & VACOPT_VERBOSE) != 0;
 	instrument = (verbose || (AmAutoVacuumWorkerProcess() &&
-							  params->log_min_duration >= 0));
+							  params.log_min_duration >= 0));
 	if (instrument)
 	{
 		pg_rusage_init(&ru0);
@@ -699,9 +699,9 @@ heap_vacuum_rel(Relation rel, VacuumParams *params,
 	 * The truncate param allows user to avoid attempting relation truncation,
 	 * though it can't force truncation to happen.
 	 */
-	Assert(params->index_cleanup != VACOPTVALUE_UNSPECIFIED);
-	Assert(params->truncate != VACOPTVALUE_UNSPECIFIED &&
-		   params->truncate != VACOPTVALUE_AUTO);
+	Assert(params.index_cleanup != VACOPTVALUE_UNSPECIFIED);
+	Assert(params.truncate != VACOPTVALUE_UNSPECIFIED &&
+		   params.truncate != VACOPTVALUE_AUTO);
 
 	/*
 	 * While VacuumFailSafeActive is reset to false before calling this, we
@@ -711,14 +711,14 @@ heap_vacuum_rel(Relation rel, VacuumParams *params,
 	vacrel->consider_bypass_optimization = true;
 	vacrel->do_index_vacuuming = true;
 	vacrel->do_index_cleanup = true;
-	vacrel->do_rel_truncate = (params->truncate != VACOPTVALUE_DISABLED);
-	if (params->index_cleanup == VACOPTVALUE_DISABLED)
+	vacrel->do_rel_truncate = (params.truncate != VACOPTVALUE_DISABLED);
+	if (params.index_cleanup == VACOPTVALUE_DISABLED)
 	{
 		/* Force disable index vacuuming up-front */
 		vacrel->do_index_vacuuming = false;
 		vacrel->do_index_cleanup = false;
 	}
-	else if (params->index_cleanup == VACOPTVALUE_ENABLED)
+	else if (params.index_cleanup == VACOPTVALUE_ENABLED)
 	{
 		/* Force index vacuuming.  Note that failsafe can still bypass. */
 		vacrel->consider_bypass_optimization = false;
@@ -726,7 +726,7 @@ heap_vacuum_rel(Relation rel, VacuumParams *params,
 	else
 	{
 		/* Default/auto, make all decisions dynamically */
-		Assert(params->index_cleanup == VACOPTVALUE_AUTO);
+		Assert(params.index_cleanup == VACOPTVALUE_AUTO);
 	}
 
 	/* Initialize page counters explicitly (be tidy) */
@@ -789,7 +789,7 @@ heap_vacuum_rel(Relation rel, VacuumParams *params,
 	 */
 	vacrel->skippedallvis = false;
 	skipwithvm = true;
-	if (params->options & VACOPT_DISABLE_PAGE_SKIPPING)
+	if (params.options & VACOPT_DISABLE_PAGE_SKIPPING)
 	{
 		/*
 		 * Force aggressive mode, and disable skipping blocks using the
@@ -830,7 +830,7 @@ heap_vacuum_rel(Relation rel, VacuumParams *params,
 	 * is already dangerously old.)
 	 */
 	lazy_check_wraparound_failsafe(vacrel);
-	dead_items_alloc(vacrel, params->nworkers);
+	dead_items_alloc(vacrel, params.nworkers);
 
 	/*
 	 * Call lazy_scan_heap to perform all required heap pruning, index
@@ -947,9 +947,9 @@ heap_vacuum_rel(Relation rel, VacuumParams *params,
 	{
 		TimestampTz endtime = GetCurrentTimestamp();
 
-		if (verbose || params->log_min_duration == 0 ||
+		if (verbose || params.log_min_duration == 0 ||
 			TimestampDifferenceExceeds(starttime, endtime,
-									   params->log_min_duration))
+									   params.log_min_duration))
 		{
 			long		secs_dur;
 			int			usecs_dur;
@@ -984,10 +984,10 @@ heap_vacuum_rel(Relation rel, VacuumParams *params,
 				 * Aggressiveness already reported earlier, in dedicated
 				 * VACUUM VERBOSE ereport
 				 */
-				Assert(!params->is_wraparound);
+				Assert(!params.is_wraparound);
 				msgfmt = _("finished vacuuming \"%s.%s.%s\": index scans: %d\n");
 			}
-			else if (params->is_wraparound)
+			else if (params.is_wraparound)
 			{
 				/*
 				 * While it's possible for a VACUUM to be both is_wraparound
@@ -1245,6 +1245,7 @@ lazy_scan_heap(LVRelState *vacrel)
 		Buffer		buf;
 		Page		page;
 		uint8		blk_info = 0;
+		int			ndeleted = 0;
 		bool		has_lpdead_items;
 		void	   *per_buffer_data = NULL;
 		bool		vm_page_frozen = false;
@@ -1387,10 +1388,10 @@ lazy_scan_heap(LVRelState *vacrel)
 		 * line pointers previously marked LP_DEAD.
 		 */
 		if (got_cleanup_lock)
-			lazy_scan_prune(vacrel, buf, blkno, page,
-							vmbuffer,
-							blk_info & VAC_BLK_ALL_VISIBLE_ACCORDING_TO_VM,
-							&has_lpdead_items, &vm_page_frozen);
+			ndeleted = lazy_scan_prune(vacrel, buf, blkno, page,
+									   vmbuffer,
+									   blk_info & VAC_BLK_ALL_VISIBLE_ACCORDING_TO_VM,
+									   &has_lpdead_items, &vm_page_frozen);
 
 		/*
 		 * Count an eagerly scanned page as a failure or a success.
@@ -1481,7 +1482,7 @@ lazy_scan_heap(LVRelState *vacrel)
 			 * table has indexes. There will only be newly-freed space if we
 			 * held the cleanup lock and lazy_scan_prune() was called.
 			 */
-			if (got_cleanup_lock && vacrel->nindexes == 0 && has_lpdead_items &&
+			if (got_cleanup_lock && vacrel->nindexes == 0 && ndeleted > 0 &&
 				blkno - next_fsm_block_to_vacuum >= VACUUM_FSM_EVERY_PAGES)
 			{
 				FreeSpaceMapVacuumRange(vacrel->rel, next_fsm_block_to_vacuum,
@@ -1936,8 +1937,10 @@ cmpOffsetNumbers(const void *a, const void *b)
  * *vm_page_frozen is set to true if the page is newly set all-frozen in the
  * VM. The caller currently only uses this for determining whether an eagerly
  * scanned page was successfully set all-frozen.
+ *
+ * Returns the number of tuples deleted from the page during HOT pruning.
  */
-static void
+static int
 lazy_scan_prune(LVRelState *vacrel,
 				Buffer buf,
 				BlockNumber blkno,
@@ -2208,6 +2211,8 @@ lazy_scan_prune(LVRelState *vacrel,
 			*vm_page_frozen = true;
 		}
 	}
+
+	return presult.ndeleted;
 }
 
 /*
diff --git a/src/backend/access/heap/visibilitymap.c b/src/backend/access/heap/visibilitymap.c
index 745a04ef26e29..8f918e00af7ed 100644
--- a/src/backend/access/heap/visibilitymap.c
+++ b/src/backend/access/heap/visibilitymap.c
@@ -364,7 +364,7 @@ visibilitymap_get_status(Relation rel, BlockNumber heapBlk, Buffer *vmbuf)
 	{
 		*vmbuf = vm_readbuf(rel, mapBlock, false);
 		if (!BufferIsValid(*vmbuf))
-			return false;
+			return (uint8) 0;
 	}
 
 	map = PageGetContents(BufferGetPage(*vmbuf));
diff --git a/src/backend/access/index/amapi.c b/src/backend/access/index/amapi.c
index f0f4f974bcedb..60684c5342279 100644
--- a/src/backend/access/index/amapi.c
+++ b/src/backend/access/index/amapi.c
@@ -42,6 +42,19 @@ GetIndexAmRoutine(Oid amhandler)
 		elog(ERROR, "index access method handler function %u did not return an IndexAmRoutine struct",
 			 amhandler);
 
+	/* Assert that all required callbacks are present. */
+	Assert(routine->ambuild != NULL);
+	Assert(routine->ambuildempty != NULL);
+	Assert(routine->aminsert != NULL);
+	Assert(routine->ambulkdelete != NULL);
+	Assert(routine->amvacuumcleanup != NULL);
+	Assert(routine->amcostestimate != NULL);
+	Assert(routine->amoptions != NULL);
+	Assert(routine->amvalidate != NULL);
+	Assert(routine->ambeginscan != NULL);
+	Assert(routine->amrescan != NULL);
+	Assert(routine->amendscan != NULL);
+
 	return routine;
 }
 
diff --git a/src/backend/access/nbtree/nbtcompare.c b/src/backend/access/nbtree/nbtcompare.c
index 4da5a3c1d161d..e1b52acd20dc2 100644
--- a/src/backend/access/nbtree/nbtcompare.c
+++ b/src/backend/access/nbtree/nbtcompare.c
@@ -555,7 +555,7 @@ btcharcmp(PG_FUNCTION_ARGS)
 static Datum
 char_decrement(Relation rel, Datum existing, bool *underflow)
 {
-	uint8		cexisting = UInt8GetDatum(existing);
+	uint8		cexisting = DatumGetUInt8(existing);
 
 	if (cexisting == 0)
 	{
@@ -571,7 +571,7 @@ char_decrement(Relation rel, Datum existing, bool *underflow)
 static Datum
 char_increment(Relation rel, Datum existing, bool *overflow)
 {
-	uint8		cexisting = UInt8GetDatum(existing);
+	uint8		cexisting = DatumGetUInt8(existing);
 
 	if (cexisting == UCHAR_MAX)
 	{
diff --git a/src/backend/access/nbtree/nbtpreprocesskeys.c b/src/backend/access/nbtree/nbtpreprocesskeys.c
index a136e4bbfdfb5..21c519cd108ed 100644
--- a/src/backend/access/nbtree/nbtpreprocesskeys.c
+++ b/src/backend/access/nbtree/nbtpreprocesskeys.c
@@ -16,6 +16,7 @@
 #include "postgres.h"
 
 #include "access/nbtree.h"
+#include "common/int.h"
 #include "lib/qunique.h"
 #include "utils/array.h"
 #include "utils/lsyscache.h"
@@ -56,6 +57,8 @@ static void _bt_skiparray_strat_decrement(IndexScanDesc scan, ScanKey arraysk,
 										  BTArrayKeyInfo *array);
 static void _bt_skiparray_strat_increment(IndexScanDesc scan, ScanKey arraysk,
 										  BTArrayKeyInfo *array);
+static void _bt_unmark_keys(IndexScanDesc scan, int *keyDataMap);
+static int	_bt_reorder_array_cmp(const void *a, const void *b);
 static ScanKey _bt_preprocess_array_keys(IndexScanDesc scan, int *new_numberOfKeys);
 static void _bt_preprocess_array_keys_final(IndexScanDesc scan, int *keyDataMap);
 static int	_bt_num_array_keys(IndexScanDesc scan, Oid *skip_eq_ops_out,
@@ -96,7 +99,7 @@ static int	_bt_compare_array_elements(const void *a, const void *b, void *arg);
  * incomplete sets of cross-type operators, we may fail to detect redundant
  * or contradictory keys, but we can survive that.)
  *
- * The output keys must be sorted by index attribute.  Presently we expect
+ * Required output keys are sorted by index attribute.  Presently we expect
  * (but verify) that the input keys are already so sorted --- this is done
  * by match_clauses_to_index() in indxpath.c.  Some reordering of the keys
  * within each attribute may be done as a byproduct of the processing here.
@@ -127,29 +130,36 @@ static int	_bt_compare_array_elements(const void *a, const void *b, void *arg);
  * This has the potential to be much more efficient than a full index scan
  * (though it behaves like a full scan when there's many distinct "x" values).
  *
- * If possible, redundant keys are eliminated: we keep only the tightest
+ * Typically, redundant keys are eliminated: we keep only the tightest
  * >/>= bound and the tightest </<= bound, and if there's an = key then
  * that's the only one returned.  (So, we return either a single = key,
  * or one or two boundary-condition keys for each attr.)  However, if we
  * cannot compare two keys for lack of a suitable cross-type operator,
- * we cannot eliminate either.  If there are two such keys of the same
- * operator strategy, the second one is just pushed into the output array
- * without further processing here.  We may also emit both >/>= or both
- * </<= keys if we can't compare them.  The logic about required keys still
- * works if we don't eliminate redundant keys.
- *
- * Note that one reason we need direction-sensitive required-key flags is
- * precisely that we may not be able to eliminate redundant keys.  Suppose
- * we have "x > 4::int AND x > 10::bigint", and we are unable to determine
- * which key is more restrictive for lack of a suitable cross-type operator.
- * _bt_first will arbitrarily pick one of the keys to do the initial
- * positioning with.  If it picks x > 4, then the x > 10 condition will fail
- * until we reach index entries > 10; but we can't stop the scan just because
- * x > 10 is failing.  On the other hand, if we are scanning backwards, then
- * failure of either key is indeed enough to stop the scan.  (In general, when
- * inequality keys are present, the initial-positioning code only promises to
- * position before the first possible match, not exactly at the first match,
- * for a forward scan; or after the last match for a backward scan.)
+ * we cannot eliminate either key.
+ *
+ * When all redundant keys could not be eliminated, we'll output a key array
+ * that can more or less be treated as if it had no redundant keys.  Suppose
+ * we have "x > 4::int AND x > 10::bigint AND x < 70", and we are unable to
+ * determine which > key is more restrictive for lack of a suitable cross-type
+ * operator.  We'll arbitrarily pick one of the > keys; the other > key won't
+ * be marked required.  Obviously, the scan will be less efficient if we
+ * choose x > 4 over x > 10 -- but it can still largely proceed as if there
+ * was only a single > condition.  "x > 10" will be placed at the end of the
+ * so->keyData[] output array.  It'll always be evaluated last, after the keys
+ * that could be marked required in the usual way (after "x > 4 AND x < 70").
+ * This can sometimes result in so->keyData[] keys that aren't even in index
+ * attribute order (if the qual involves multiple attributes).  The scan's
+ * required keys will still be in attribute order, though, so it can't matter.
+ *
+ * This scheme ensures that _bt_first always uses the same set of keys at the
+ * start of a forwards scan as those _bt_checkkeys uses to determine when to
+ * end a similar backwards scan (and vice-versa).  _bt_advance_array_keys
+ * depends on this: it expects to be able to reliably predict what the next
+ * _bt_first call will do by testing whether _bt_checkkeys' routines report
+ * that the final tuple on the page is past the end of matches for the scan's
+ * keys with the scan direction flipped.  If it is (if continuescan=false),
+ * then it follows that calling _bt_first will, at a minimum, relocate the
+ * scan to the very next leaf page (in the current scan direction).
  *
  * As a byproduct of this work, we can detect contradictory quals such
  * as "x = 1 AND x > 2".  If we see that, we return so->qual_ok = false,
@@ -188,7 +198,8 @@ _bt_preprocess_keys(IndexScanDesc scan)
 	int			numberOfEqualCols;
 	ScanKey		inkeys;
 	BTScanKeyPreproc xform[BTMaxStrategyNumber];
-	bool		test_result;
+	bool		test_result,
+				redundant_key_kept = false;
 	AttrNumber	attno;
 	ScanKey		arrayKeyData;
 	int		   *keyDataMap = NULL;
@@ -388,7 +399,8 @@ _bt_preprocess_keys(IndexScanDesc scan)
 						xform[j].inkey = NULL;
 						xform[j].inkeyi = -1;
 					}
-					/* else, cannot determine redundancy, keep both keys */
+					else
+						redundant_key_kept = true;
 				}
 				/* track number of attrs for which we have "=" keys */
 				numberOfEqualCols++;
@@ -409,6 +421,8 @@ _bt_preprocess_keys(IndexScanDesc scan)
 					else
 						xform[BTLessStrategyNumber - 1].inkey = NULL;
 				}
+				else
+					redundant_key_kept = true;
 			}
 
 			/* try to keep only one of >, >= */
@@ -426,6 +440,8 @@ _bt_preprocess_keys(IndexScanDesc scan)
 					else
 						xform[BTGreaterStrategyNumber - 1].inkey = NULL;
 				}
+				else
+					redundant_key_kept = true;
 			}
 
 			/*
@@ -466,25 +482,6 @@ _bt_preprocess_keys(IndexScanDesc scan)
 		/* check strategy this key's operator corresponds to */
 		j = inkey->sk_strategy - 1;
 
-		/* if row comparison, push it directly to the output array */
-		if (inkey->sk_flags & SK_ROW_HEADER)
-		{
-			ScanKey		outkey = &so->keyData[new_numberOfKeys++];
-
-			memcpy(outkey, inkey, sizeof(ScanKeyData));
-			if (arrayKeyData)
-				keyDataMap[new_numberOfKeys - 1] = i;
-			if (numberOfEqualCols == attno - 1)
-				_bt_mark_scankey_required(outkey);
-
-			/*
-			 * We don't support RowCompare using equality; such a qual would
-			 * mess up the numberOfEqualCols tracking.
-			 */
-			Assert(j != (BTEqualStrategyNumber - 1));
-			continue;
-		}
-
 		if (inkey->sk_strategy == BTEqualStrategyNumber &&
 			(inkey->sk_flags & SK_SEARCHARRAY))
 		{
@@ -593,9 +590,8 @@ _bt_preprocess_keys(IndexScanDesc scan)
 				 * the new scan key.
 				 *
 				 * Note: We do things this way around so that our arrays are
-				 * always in the same order as their corresponding scan keys,
-				 * even with incomplete opfamilies.  _bt_advance_array_keys
-				 * depends on this.
+				 * always in the same order as their corresponding scan keys.
+				 * _bt_preprocess_array_keys_final expects this.
 				 */
 				ScanKey		outkey = &so->keyData[new_numberOfKeys++];
 
@@ -607,6 +603,7 @@ _bt_preprocess_keys(IndexScanDesc scan)
 				xform[j].inkey = inkey;
 				xform[j].inkeyi = i;
 				xform[j].arrayidx = arrayidx;
+				redundant_key_kept = true;
 			}
 		}
 	}
@@ -622,6 +619,15 @@ _bt_preprocess_keys(IndexScanDesc scan)
 	if (arrayKeyData)
 		_bt_preprocess_array_keys_final(scan, keyDataMap);
 
+	/*
+	 * If there are remaining redundant inequality keys, we must make sure
+	 * that each index attribute has no more than one required >/>= key, and
+	 * no more than one required </<= key.  Attributes that have one or more
+	 * required = keys now must keep only one required key (the first = key).
+	 */
+	if (unlikely(redundant_key_kept) && so->qual_ok)
+		_bt_unmark_keys(scan, keyDataMap);
+
 	/* Could pfree arrayKeyData/keyDataMap now, but not worth the cycles */
 }
 
@@ -746,9 +752,12 @@ _bt_fix_scankey_strategy(ScanKey skey, int16 *indoption)
  *
  * Depending on the operator type, the key may be required for both scan
  * directions or just one.  Also, if the key is a row comparison header,
- * we have to mark its first subsidiary ScanKey as required.  (Subsequent
- * subsidiary ScanKeys are normally for lower-order columns, and thus
- * cannot be required, since they're after the first non-equality scankey.)
+ * we have to mark the appropriate subsidiary ScanKeys as required.  In such
+ * cases, the first subsidiary key is required, but subsequent ones are
+ * required only as long as they correspond to successive index columns and
+ * match the leading column as to sort direction.  Otherwise the row
+ * comparison ordering is different from the index ordering and so we can't
+ * stop the scan on the basis of those lower-order columns.
  *
  * Note: when we set required-key flag bits in a subsidiary scankey, we are
  * scribbling on a data structure belonging to the index AM's caller, not on
@@ -786,12 +795,25 @@ _bt_mark_scankey_required(ScanKey skey)
 	if (skey->sk_flags & SK_ROW_HEADER)
 	{
 		ScanKey		subkey = (ScanKey) DatumGetPointer(skey->sk_argument);
+		AttrNumber	attno = skey->sk_attno;
 
 		/* First subkey should be same column/operator as the header */
-		Assert(subkey->sk_flags & SK_ROW_MEMBER);
-		Assert(subkey->sk_attno == skey->sk_attno);
+		Assert(subkey->sk_attno == attno);
 		Assert(subkey->sk_strategy == skey->sk_strategy);
-		subkey->sk_flags |= addflags;
+
+		for (;;)
+		{
+			Assert(subkey->sk_flags & SK_ROW_MEMBER);
+			if (subkey->sk_attno != attno)
+				break;			/* non-adjacent key, so not required */
+			if (subkey->sk_strategy != skey->sk_strategy)
+				break;			/* wrong direction, so not required */
+			subkey->sk_flags |= addflags;
+			if (subkey->sk_flags & SK_ROW_END)
+				break;
+			subkey++;
+			attno++;
+		}
 	}
 }
 
@@ -847,8 +869,7 @@ _bt_compare_scankey_args(IndexScanDesc scan, ScanKey op,
 				cmp_op;
 	StrategyNumber strat;
 
-	Assert(!((leftarg->sk_flags | rightarg->sk_flags) &
-			 (SK_ROW_HEADER | SK_ROW_MEMBER)));
+	Assert(!((leftarg->sk_flags | rightarg->sk_flags) & SK_ROW_MEMBER));
 
 	/*
 	 * First, deal with cases where one or both args are NULL.  This should
@@ -924,6 +945,16 @@ _bt_compare_scankey_args(IndexScanDesc scan, ScanKey op,
 		return true;
 	}
 
+	/*
+	 * We don't yet know how to determine redundancy when it involves a row
+	 * compare key (barring simple cases involving IS NULL/IS NOT NULL)
+	 */
+	if ((leftarg->sk_flags | rightarg->sk_flags) & SK_ROW_HEADER)
+	{
+		Assert(!((leftarg->sk_flags | rightarg->sk_flags) & SK_BT_SKIP));
+		return false;
+	}
+
 	/*
 	 * If either leftarg or rightarg are equality-type array scankeys, we need
 	 * specialized handling (since by now we know that IS NULL wasn't used)
@@ -1467,6 +1498,283 @@ _bt_skiparray_strat_increment(IndexScanDesc scan, ScanKey arraysk,
 	}
 }
 
+/*
+ *	_bt_unmark_keys() -- make superfluous required keys nonrequired after all
+ *
+ * When _bt_preprocess_keys fails to eliminate one or more redundant keys, it
+ * calls here to make sure that no index attribute has more than one > or >=
+ * key marked required, and no more than one required < or <= key.  Attributes
+ * with = keys will always get one = key as their required key.  All other
+ * keys that were initially marked required get "unmarked" here.  That way,
+ * _bt_first and _bt_checkkeys will reliably agree on which keys to use to
+ * start and/or to end the scan.
+ *
+ * We also relocate keys that become/started out nonrequired to the end of
+ * so->keyData[].  That way, _bt_first and _bt_checkkeys cannot fail to reach
+ * a required key due to some earlier nonrequired key getting in the way.
+ *
+ * Only call here when _bt_compare_scankey_args returned false at least once
+ * (otherwise, calling here will just waste cycles).
+ */
+static void
+_bt_unmark_keys(IndexScanDesc scan, int *keyDataMap)
+{
+	BTScanOpaque so = (BTScanOpaque) scan->opaque;
+	AttrNumber	attno;
+	bool	   *unmarkikey;
+	int			nunmark,
+				nunmarked,
+				nkept,
+				firsti;
+	ScanKey		keepKeys,
+				unmarkKeys;
+	FmgrInfo   *keepOrderProcs = NULL,
+			   *unmarkOrderProcs = NULL;
+	bool		haveReqEquals,
+				haveReqForward,
+				haveReqBackward;
+
+	/*
+	 * Do an initial pass over so->keyData[] that determines which keys to
+	 * keep as required.  We expect so->keyData[] to still be in attribute
+	 * order when we're called (though we don't expect any particular order
+	 * among each attribute's keys).
+	 *
+	 * When both equality and inequality keys remain on a single attribute, we
+	 * *must* make sure that exactly one of the equalities remains required.
+	 * Any requiredness markings that we might leave on later keys/attributes
+	 * are predicated on there being required = keys on all prior columns.
+	 */
+	unmarkikey = palloc0(so->numberOfKeys * sizeof(bool));
+	nunmark = 0;
+
+	/* Set things up for first key's attribute */
+	attno = so->keyData[0].sk_attno;
+	firsti = 0;
+	haveReqEquals = false;
+	haveReqForward = false;
+	haveReqBackward = false;
+	for (int i = 0; i < so->numberOfKeys; i++)
+	{
+		ScanKey		origkey = &so->keyData[i];
+
+		if (origkey->sk_attno != attno)
+		{
+			/* Reset for next attribute */
+			attno = origkey->sk_attno;
+			firsti = i;
+
+			haveReqEquals = false;
+			haveReqForward = false;
+			haveReqBackward = false;
+		}
+
+		/* Equalities get priority over inequalities */
+		if (haveReqEquals)
+		{
+			/*
+			 * We already found the first "=" key for this attribute.  We've
+			 * already decided that all its other keys will be unmarked.
+			 */
+			Assert(!(origkey->sk_flags & SK_SEARCHNULL));
+			unmarkikey[i] = true;
+			nunmark++;
+			continue;
+		}
+		else if ((origkey->sk_flags & SK_BT_REQFWD) &&
+				 (origkey->sk_flags & SK_BT_REQBKWD))
+		{
+			/*
+			 * Found the first "=" key for attno.  All other attno keys will
+			 * be unmarked.
+			 */
+			Assert(origkey->sk_strategy == BTEqualStrategyNumber);
+
+			haveReqEquals = true;
+			for (int j = firsti; j < i; j++)
+			{
+				/* Unmark any prior inequality keys on attno after all */
+				if (!unmarkikey[j])
+				{
+					unmarkikey[j] = true;
+					nunmark++;
+				}
+			}
+			continue;
+		}
+
+		/* Deal with inequalities next */
+		if ((origkey->sk_flags & SK_BT_REQFWD) && !haveReqForward)
+		{
+			haveReqForward = true;
+			continue;
+		}
+		else if ((origkey->sk_flags & SK_BT_REQBKWD) && !haveReqBackward)
+		{
+			haveReqBackward = true;
+			continue;
+		}
+
+		/*
+		 * We have either a redundant inequality key that will be unmarked, or
+		 * we have a key that wasn't marked required in the first place
+		 */
+		unmarkikey[i] = true;
+		nunmark++;
+	}
+
+	/* Should only be called when _bt_compare_scankey_args reported failure */
+	Assert(nunmark > 0);
+
+	/*
+	 * Next, allocate temp arrays: one for required keys that'll remain
+	 * required, the other for all remaining keys
+	 */
+	unmarkKeys = palloc(nunmark * sizeof(ScanKeyData));
+	keepKeys = palloc((so->numberOfKeys - nunmark) * sizeof(ScanKeyData));
+	nunmarked = 0;
+	nkept = 0;
+	if (so->numArrayKeys)
+	{
+		unmarkOrderProcs = palloc(nunmark * sizeof(FmgrInfo));
+		keepOrderProcs = palloc((so->numberOfKeys - nunmark) * sizeof(FmgrInfo));
+	}
+
+	/*
+	 * Next, copy the contents of so->keyData[] into the appropriate temp
+	 * array.
+	 *
+	 * Scans with = array keys need us to maintain invariants around the order
+	 * of so->orderProcs[] and so->arrayKeys[] relative to so->keyData[].  See
+	 * _bt_preprocess_array_keys_final for a full explanation.
+	 */
+	for (int i = 0; i < so->numberOfKeys; i++)
+	{
+		ScanKey		origkey = &so->keyData[i];
+		ScanKey		unmark;
+
+		if (!unmarkikey[i])
+		{
+			/*
+			 * Key gets to keep its original requiredness markings.
+			 *
+			 * Key will stay in its original position, unless we're going to
+			 * unmark an earlier key (in which case this key gets moved back).
+			 */
+			memcpy(keepKeys + nkept, origkey, sizeof(ScanKeyData));
+
+			if (so->numArrayKeys)
+			{
+				keyDataMap[i] = nkept;
+				memcpy(keepOrderProcs + nkept, &so->orderProcs[i],
+					   sizeof(FmgrInfo));
+			}
+
+			nkept++;
+			continue;
+		}
+
+		/*
+		 * Key will be unmarked as needed, and moved to the end of the array,
+		 * next to other keys that will become (or always were) nonrequired
+		 */
+		unmark = unmarkKeys + nunmarked;
+		memcpy(unmark, origkey, sizeof(ScanKeyData));
+
+		if (so->numArrayKeys)
+		{
+			keyDataMap[i] = (so->numberOfKeys - nunmark) + nunmarked;
+			memcpy(&unmarkOrderProcs[nunmarked], &so->orderProcs[i],
+				   sizeof(FmgrInfo));
+		}
+
+		/*
+		 * Preprocessing only generates skip arrays when it knows that they'll
+		 * be the only required = key on the attr.  We'll never unmark them.
+		 */
+		Assert(!(unmark->sk_flags & SK_BT_SKIP));
+
+		/*
+		 * Also shouldn't have to unmark an IS NULL or an IS NOT NULL key.
+		 * They aren't cross-type, so an incomplete opfamily can't matter.
+		 */
+		Assert(!(unmark->sk_flags & SK_ISNULL) ||
+			   !(unmark->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD)));
+
+		/* Clear requiredness flags on redundant key (and on any subkeys) */
+		unmark->sk_flags &= ~(SK_BT_REQFWD | SK_BT_REQBKWD);
+		if (unmark->sk_flags & SK_ROW_HEADER)
+		{
+			ScanKey		subkey = (ScanKey) DatumGetPointer(unmark->sk_argument);
+
+			Assert(subkey->sk_strategy == unmark->sk_strategy);
+			for (;;)
+			{
+				Assert(subkey->sk_flags & SK_ROW_MEMBER);
+				subkey->sk_flags &= ~(SK_BT_REQFWD | SK_BT_REQBKWD);
+				if (subkey->sk_flags & SK_ROW_END)
+					break;
+				subkey++;
+			}
+		}
+
+		nunmarked++;
+	}
+
+	/* Copy both temp arrays back into so->keyData[] to reorder */
+	Assert(nkept == so->numberOfKeys - nunmark);
+	Assert(nunmarked == nunmark);
+	memcpy(so->keyData, keepKeys, sizeof(ScanKeyData) * nkept);
+	memcpy(so->keyData + nkept, unmarkKeys, sizeof(ScanKeyData) * nunmarked);
+
+	/* Done with temp arrays */
+	pfree(unmarkikey);
+	pfree(keepKeys);
+	pfree(unmarkKeys);
+
+	/*
+	 * Now copy so->orderProcs[] temp entries needed by scans with = array
+	 * keys back (just like with the so->keyData[] temp arrays)
+	 */
+	if (so->numArrayKeys)
+	{
+		memcpy(so->orderProcs, keepOrderProcs, sizeof(FmgrInfo) * nkept);
+		memcpy(so->orderProcs + nkept, unmarkOrderProcs,
+			   sizeof(FmgrInfo) * nunmarked);
+
+		/* Also fix-up array->scan_key references */
+		for (int arridx = 0; arridx < so->numArrayKeys; arridx++)
+		{
+			BTArrayKeyInfo *array = &so->arrayKeys[arridx];
+
+			array->scan_key = keyDataMap[array->scan_key];
+		}
+
+		/*
+		 * Sort so->arrayKeys[] based on its new BTArrayKeyInfo.scan_key
+		 * offsets, so that its order matches so->keyData[] order as expected
+		 */
+		qsort(so->arrayKeys, so->numArrayKeys, sizeof(BTArrayKeyInfo),
+			  _bt_reorder_array_cmp);
+
+		/* Done with temp arrays */
+		pfree(unmarkOrderProcs);
+		pfree(keepOrderProcs);
+	}
+}
+
+/*
+ * qsort comparator for reordering so->arrayKeys[] BTArrayKeyInfo entries
+ */
+static int
+_bt_reorder_array_cmp(const void *a, const void *b)
+{
+	BTArrayKeyInfo *arraya = (BTArrayKeyInfo *) a;
+	BTArrayKeyInfo *arrayb = (BTArrayKeyInfo *) b;
+
+	return pg_cmp_s32(arraya->scan_key, arrayb->scan_key);
+}
+
 /*
  *	_bt_preprocess_array_keys() -- Preprocess SK_SEARCHARRAY scan keys
  *
diff --git a/src/backend/access/nbtree/nbtsearch.c b/src/backend/access/nbtree/nbtsearch.c
index 36544ecfd5878..d69798795b43b 100644
--- a/src/backend/access/nbtree/nbtsearch.c
+++ b/src/backend/access/nbtree/nbtsearch.c
@@ -892,9 +892,9 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
 	OffsetNumber offnum;
 	BTScanInsertData inskey;
 	ScanKey		startKeys[INDEX_MAX_KEYS];
-	ScanKeyData notnullkeys[INDEX_MAX_KEYS];
+	ScanKeyData notnullkey;
 	int			keysz = 0;
-	StrategyNumber strat_total;
+	StrategyNumber strat_total = InvalidStrategy;
 	BlockNumber blkno = InvalidBlockNumber,
 				lastcurrblkno;
 
@@ -960,46 +960,51 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
 
 	/*----------
 	 * Examine the scan keys to discover where we need to start the scan.
+	 * The selected scan keys (at most one per index column) are remembered by
+	 * storing their addresses into the local startKeys[] array.  The final
+	 * startKeys[] entry's strategy is set in strat_total. (Actually, there
+	 * are a couple of cases where we force a less/more restrictive strategy.)
 	 *
-	 * We want to identify the keys that can be used as starting boundaries;
-	 * these are =, >, or >= keys for a forward scan or =, <, <= keys for
-	 * a backwards scan.  We can use keys for multiple attributes so long as
-	 * the prior attributes had only =, >= (resp. =, <=) keys.  Once we accept
-	 * a > or < boundary or find an attribute with no boundary (which can be
-	 * thought of as the same as "> -infinity"), we can't use keys for any
-	 * attributes to its right, because it would break our simplistic notion
-	 * of what initial positioning strategy to use.
+	 * We must use the key that was marked required (in the direction opposite
+	 * our own scan's) during preprocessing.  Each index attribute can only
+	 * have one such required key.  In general, the keys that we use to find
+	 * an initial position when scanning forwards are the same keys that end
+	 * the scan on the leaf level when scanning backwards (and vice-versa).
 	 *
 	 * When the scan keys include cross-type operators, _bt_preprocess_keys
-	 * may not be able to eliminate redundant keys; in such cases we will
-	 * arbitrarily pick a usable one for each attribute.  This is correct
-	 * but possibly not optimal behavior.  (For example, with keys like
-	 * "x >= 4 AND x >= 5" we would elect to scan starting at x=4 when
-	 * x=5 would be more efficient.)  Since the situation only arises given
-	 * a poorly-worded query plus an incomplete opfamily, live with it.
+	 * may not be able to eliminate redundant keys; in such cases it will
+	 * arbitrarily pick a usable key for each attribute (and scan direction),
+	 * ensuring that there is no more than one key required in each direction.
+	 * We stop considering further keys once we reach the first nonrequired
+	 * key (which must come after all required keys), so this can't affect us.
+	 *
+	 * The required keys that we use as starting boundaries have to be =, >,
+	 * or >= keys for a forward scan or =, <, <= keys for a backwards scan.
+	 * We can use keys for multiple attributes so long as the prior attributes
+	 * had only =, >= (resp. =, <=) keys.  These rules are very similar to the
+	 * rules that preprocessing used to determine which keys to mark required.
+	 * We cannot always use every required key as a positioning key, though.
+	 * Skip arrays necessitate independently applying our own rules here.
+	 * Skip arrays are always generally considered = array keys, but we'll
+	 * nevertheless treat them as inequalities at certain points of the scan.
+	 * When that happens, it _might_ have implications for the number of
+	 * required keys that we can safely use for initial positioning purposes.
 	 *
-	 * When both equality and inequality keys appear for a single attribute
-	 * (again, only possible when cross-type operators appear), we *must*
-	 * select one of the equality keys for the starting point, because
-	 * _bt_checkkeys() will stop the scan as soon as an equality qual fails.
-	 * For example, if we have keys like "x >= 4 AND x = 10" and we elect to
-	 * start at x=4, we will fail and stop before reaching x=10.  If multiple
-	 * equality quals survive preprocessing, however, it doesn't matter which
-	 * one we use --- by definition, they are either redundant or
-	 * contradictory.
+	 * For example, a forward scan with a skip array on its leading attribute
+	 * (with no low_compare/high_compare) will have at least two required scan
+	 * keys, but we won't use any of them as boundary keys during the scan's
+	 * initial call here.  Our positioning key during the first call here can
+	 * be thought of as representing "> -infinity".  Similarly, if such a skip
+	 * array's low_compare is "a > 'foo'", then we position using "a > 'foo'"
+	 * during the scan's initial call here; a lower-order key such as "b = 42"
+	 * can't be used until the "a" array advances beyond MINVAL/low_compare.
 	 *
-	 * In practice we rarely see any "attribute boundary key gaps" here.
-	 * Preprocessing can usually backfill skip array keys for any attributes
-	 * that were omitted from the original scan->keyData[] input keys.  All
-	 * array keys are always considered = keys, but we'll sometimes need to
-	 * treat the current key value as if we were using an inequality strategy.
-	 * This happens with range skip arrays, which store inequality keys in the
-	 * array's low_compare/high_compare fields (used to find the first/last
-	 * set of matches, when = key will lack a usable sk_argument value).
-	 * These are always preferred over any redundant "standard" inequality
-	 * keys on the same column (per the usual rule about preferring = keys).
-	 * Note also that any column with an = skip array key can never have an
-	 * additional, contradictory = key.
+	 * On the other hand, if such a skip array's low_compare was "a >= 'foo'",
+	 * then we _can_ use "a >= 'foo' AND b = 42" during the initial call here.
+	 * A subsequent call here might have us use "a = 'fop' AND b = 42".  Note
+	 * that we treat = and >= as equivalent when scanning forwards (just as we
+	 * treat = and <= as equivalent when scanning backwards).  We effectively
+	 * do the same thing (though with a distinct "a" element/value) each time.
 	 *
 	 * All keys (with the exception of SK_SEARCHNULL keys and SK_BT_SKIP
 	 * array keys whose array is "null_elem=true") imply a NOT NULL qualifier.
@@ -1011,41 +1016,38 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
 	 * traversing a lot of null entries at the start of the scan.
 	 *
 	 * In this loop, row-comparison keys are treated the same as keys on their
-	 * first (leftmost) columns.  We'll add on lower-order columns of the row
-	 * comparison below, if possible.
+	 * first (leftmost) columns.  We'll add all lower-order columns of the row
+	 * comparison that were marked required during preprocessing below.
 	 *
-	 * The selected scan keys (at most one per index column) are remembered by
-	 * storing their addresses into the local startKeys[] array.
-	 *
-	 * _bt_checkkeys/_bt_advance_array_keys decide whether and when to start
-	 * the next primitive index scan (for scans with array keys) based in part
-	 * on an understanding of how it'll enable us to reposition the scan.
-	 * They're directly aware of how we'll sometimes cons up an explicit
-	 * SK_SEARCHNOTNULL key.  They'll even end primitive scans by applying a
-	 * symmetric "deduce NOT NULL" rule of their own.  This allows top-level
-	 * scans to skip large groups of NULLs through repeated deductions about
-	 * key strictness (for a required inequality key) and whether NULLs in the
-	 * key's index column are stored last or first (relative to non-NULLs).
+	 * _bt_advance_array_keys needs to know exactly how we'll reposition the
+	 * scan (should it opt to schedule another primitive index scan).  It is
+	 * critical that primscans only be scheduled when they'll definitely make
+	 * some useful progress.  _bt_advance_array_keys does this by calling
+	 * _bt_checkkeys routines that report whether a tuple is past the end of
+	 * matches for the scan's keys (given the scan's current array elements).
+	 * If the page's final tuple is "after the end of matches" for a scan that
+	 * uses the *opposite* scan direction, then it must follow that it's also
+	 * "before the start of matches" for the actual current scan direction.
+	 * It is therefore essential that all of our initial positioning rules are
+	 * symmetric with _bt_checkkeys's corresponding continuescan=false rule.
 	 * If you update anything here, _bt_checkkeys/_bt_advance_array_keys might
 	 * need to be kept in sync.
 	 *----------
 	 */
-	strat_total = BTEqualStrategyNumber;
 	if (so->numberOfKeys > 0)
 	{
 		AttrNumber	curattr;
-		ScanKey		chosen;
+		ScanKey		bkey;
 		ScanKey		impliesNN;
 		ScanKey		cur;
 
 		/*
-		 * chosen is the so-far-chosen key for the current attribute, if any.
-		 * We don't cast the decision in stone until we reach keys for the
-		 * next attribute.
+		 * bkey will be set to the key that preprocessing left behind as the
+		 * boundary key for this attribute, in this scan direction (if any)
 		 */
 		cur = so->keyData;
 		curattr = 1;
-		chosen = NULL;
+		bkey = NULL;
 		/* Also remember any scankey that implies a NOT NULL constraint */
 		impliesNN = NULL;
 
@@ -1058,23 +1060,29 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
 		{
 			if (i >= so->numberOfKeys || cur->sk_attno != curattr)
 			{
+				/* Done looking for the curattr boundary key */
+				Assert(bkey == NULL ||
+					   (bkey->sk_attno == curattr &&
+						(bkey->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD))));
+				Assert(impliesNN == NULL ||
+					   (impliesNN->sk_attno == curattr &&
+						(impliesNN->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD))));
+
 				/*
-				 * Done looking at keys for curattr.
-				 *
 				 * If this is a scan key for a skip array whose current
 				 * element is MINVAL, choose low_compare (when scanning
 				 * backwards it'll be MAXVAL, and we'll choose high_compare).
 				 *
-				 * Note: if the array's low_compare key makes 'chosen' NULL,
+				 * Note: if the array's low_compare key makes 'bkey' NULL,
 				 * then we behave as if the array's first element is -inf,
 				 * except when !array->null_elem implies a usable NOT NULL
 				 * constraint.
 				 */
-				if (chosen != NULL &&
-					(chosen->sk_flags & (SK_BT_MINVAL | SK_BT_MAXVAL)))
+				if (bkey != NULL &&
+					(bkey->sk_flags & (SK_BT_MINVAL | SK_BT_MAXVAL)))
 				{
-					int			ikey = chosen - so->keyData;
-					ScanKey		skipequalitykey = chosen;
+					int			ikey = bkey - so->keyData;
+					ScanKey		skipequalitykey = bkey;
 					BTArrayKeyInfo *array = NULL;
 
 					for (int arridx = 0; arridx < so->numArrayKeys; arridx++)
@@ -1087,42 +1095,41 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
 					if (ScanDirectionIsForward(dir))
 					{
 						Assert(!(skipequalitykey->sk_flags & SK_BT_MAXVAL));
-						chosen = array->low_compare;
+						bkey = array->low_compare;
 					}
 					else
 					{
 						Assert(!(skipequalitykey->sk_flags & SK_BT_MINVAL));
-						chosen = array->high_compare;
+						bkey = array->high_compare;
 					}
 
-					Assert(chosen == NULL ||
-						   chosen->sk_attno == skipequalitykey->sk_attno);
+					Assert(bkey == NULL ||
+						   bkey->sk_attno == skipequalitykey->sk_attno);
 
 					if (!array->null_elem)
 						impliesNN = skipequalitykey;
 					else
-						Assert(chosen == NULL && impliesNN == NULL);
+						Assert(bkey == NULL && impliesNN == NULL);
 				}
 
 				/*
 				 * If we didn't find a usable boundary key, see if we can
 				 * deduce a NOT NULL key
 				 */
-				if (chosen == NULL && impliesNN != NULL &&
+				if (bkey == NULL && impliesNN != NULL &&
 					((impliesNN->sk_flags & SK_BT_NULLS_FIRST) ?
 					 ScanDirectionIsForward(dir) :
 					 ScanDirectionIsBackward(dir)))
 				{
-					/* Yes, so build the key in notnullkeys[keysz] */
-					chosen = &notnullkeys[keysz];
-					ScanKeyEntryInitialize(chosen,
+					/* Final startKeys[] entry will be deduced NOT NULL key */
+					bkey = &notnullkey;
+					ScanKeyEntryInitialize(bkey,
 										   (SK_SEARCHNOTNULL | SK_ISNULL |
 											(impliesNN->sk_flags &
 											 (SK_BT_DESC | SK_BT_NULLS_FIRST))),
 										   curattr,
-										   ((impliesNN->sk_flags & SK_BT_NULLS_FIRST) ?
-											BTGreaterStrategyNumber :
-											BTLessStrategyNumber),
+										   ScanDirectionIsForward(dir) ?
+										   BTGreaterStrategyNumber : BTLessStrategyNumber,
 										   InvalidOid,
 										   InvalidOid,
 										   InvalidOid,
@@ -1130,12 +1137,12 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
 				}
 
 				/*
-				 * If we still didn't find a usable boundary key, quit; else
-				 * save the boundary key pointer in startKeys.
+				 * If preprocessing didn't leave a usable boundary key, quit;
+				 * else save the boundary key pointer in startKeys[]
 				 */
-				if (chosen == NULL)
+				if (bkey == NULL)
 					break;
-				startKeys[keysz++] = chosen;
+				startKeys[keysz++] = bkey;
 
 				/*
 				 * We can only consider adding more boundary keys when the one
@@ -1143,7 +1150,7 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
 				 * (during backwards scans we can only do so when the key that
 				 * we just added to startKeys[] uses the = or <= strategy)
 				 */
-				strat_total = chosen->sk_strategy;
+				strat_total = bkey->sk_strategy;
 				if (strat_total == BTGreaterStrategyNumber ||
 					strat_total == BTLessStrategyNumber)
 					break;
@@ -1154,19 +1161,19 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
 				 * make strat_total > or < (and stop adding boundary keys).
 				 * This can only happen with opclasses that lack skip support.
 				 */
-				if (chosen->sk_flags & (SK_BT_NEXT | SK_BT_PRIOR))
+				if (bkey->sk_flags & (SK_BT_NEXT | SK_BT_PRIOR))
 				{
-					Assert(chosen->sk_flags & SK_BT_SKIP);
+					Assert(bkey->sk_flags & SK_BT_SKIP);
 					Assert(strat_total == BTEqualStrategyNumber);
 
 					if (ScanDirectionIsForward(dir))
 					{
-						Assert(!(chosen->sk_flags & SK_BT_PRIOR));
+						Assert(!(bkey->sk_flags & SK_BT_PRIOR));
 						strat_total = BTGreaterStrategyNumber;
 					}
 					else
 					{
-						Assert(!(chosen->sk_flags & SK_BT_NEXT));
+						Assert(!(bkey->sk_flags & SK_BT_NEXT));
 						strat_total = BTLessStrategyNumber;
 					}
 
@@ -1180,24 +1187,30 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
 
 				/*
 				 * Done if that was the last scan key output by preprocessing.
-				 * Also done if there is a gap index attribute that lacks a
-				 * usable key (only possible when preprocessing was unable to
-				 * generate a skip array key to "fill in the gap").
+				 * Also done if we've now examined all keys marked required.
 				 */
 				if (i >= so->numberOfKeys ||
-					cur->sk_attno != curattr + 1)
+					!(cur->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD)))
 					break;
 
 				/*
 				 * Reset for next attr.
 				 */
+				Assert(cur->sk_attno == curattr + 1);
 				curattr = cur->sk_attno;
-				chosen = NULL;
+				bkey = NULL;
 				impliesNN = NULL;
 			}
 
 			/*
-			 * Can we use this key as a starting boundary for this attr?
+			 * If we've located the starting boundary key for curattr, we have
+			 * no interest in curattr's other required key
+			 */
+			if (bkey != NULL)
+				continue;
+
+			/*
+			 * Is this key the starting boundary key for curattr?
 			 *
 			 * If not, does it imply a NOT NULL constraint?  (Because
 			 * SK_SEARCHNULL keys are always assigned BTEqualStrategyNumber,
@@ -1207,27 +1220,20 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
 			{
 				case BTLessStrategyNumber:
 				case BTLessEqualStrategyNumber:
-					if (chosen == NULL)
-					{
-						if (ScanDirectionIsBackward(dir))
-							chosen = cur;
-						else
-							impliesNN = cur;
-					}
+					if (ScanDirectionIsBackward(dir))
+						bkey = cur;
+					else if (impliesNN == NULL)
+						impliesNN = cur;
 					break;
 				case BTEqualStrategyNumber:
-					/* override any non-equality choice */
-					chosen = cur;
+					bkey = cur;
 					break;
 				case BTGreaterEqualStrategyNumber:
 				case BTGreaterStrategyNumber:
-					if (chosen == NULL)
-					{
-						if (ScanDirectionIsForward(dir))
-							chosen = cur;
-						else
-							impliesNN = cur;
-					}
+					if (ScanDirectionIsForward(dir))
+						bkey = cur;
+					else if (impliesNN == NULL)
+						impliesNN = cur;
 					break;
 			}
 		}
@@ -1253,16 +1259,18 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
 	Assert(keysz <= INDEX_MAX_KEYS);
 	for (int i = 0; i < keysz; i++)
 	{
-		ScanKey		cur = startKeys[i];
+		ScanKey		bkey = startKeys[i];
 
-		Assert(cur->sk_attno == i + 1);
+		Assert(bkey->sk_attno == i + 1);
 
-		if (cur->sk_flags & SK_ROW_HEADER)
+		if (bkey->sk_flags & SK_ROW_HEADER)
 		{
 			/*
 			 * Row comparison header: look to the first row member instead
 			 */
-			ScanKey		subkey = (ScanKey) DatumGetPointer(cur->sk_argument);
+			ScanKey		subkey = (ScanKey) DatumGetPointer(bkey->sk_argument);
+			bool		loosen_strat = false,
+						tighten_strat = false;
 
 			/*
 			 * Cannot be a NULL in the first row member: _bt_preprocess_keys
@@ -1270,9 +1278,18 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
 			 * ever getting this far
 			 */
 			Assert(subkey->sk_flags & SK_ROW_MEMBER);
-			Assert(subkey->sk_attno == cur->sk_attno);
+			Assert(subkey->sk_attno == bkey->sk_attno);
 			Assert(!(subkey->sk_flags & SK_ISNULL));
 
+			/*
+			 * This is either a > or >= key (during backwards scans it is
+			 * either < or <=) that was marked required during preprocessing.
+			 * Later so->keyData[] keys can't have been marked required, so
+			 * our row compare header key must be the final startKeys[] entry.
+			 */
+			Assert(subkey->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD));
+			Assert(i == keysz - 1);
+
 			/*
 			 * The member scankeys are already in insertion format (ie, they
 			 * have sk_func = 3-way-comparison function)
@@ -1280,112 +1297,141 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
 			memcpy(inskey.scankeys + i, subkey, sizeof(ScanKeyData));
 
 			/*
-			 * If the row comparison is the last positioning key we accepted,
-			 * try to add additional keys from the lower-order row members.
-			 * (If we accepted independent conditions on additional index
-			 * columns, we use those instead --- doesn't seem worth trying to
-			 * determine which is more restrictive.)  Note that this is OK
-			 * even if the row comparison is of ">" or "<" type, because the
-			 * condition applied to all but the last row member is effectively
-			 * ">=" or "<=", and so the extra keys don't break the positioning
-			 * scheme.  But, by the same token, if we aren't able to use all
-			 * the row members, then the part of the row comparison that we
-			 * did use has to be treated as just a ">=" or "<=" condition, and
-			 * so we'd better adjust strat_total accordingly.
+			 * Now look to later row compare members.
+			 *
+			 * If there's an "index attribute gap" between two row compare
+			 * members, the second member won't have been marked required, and
+			 * so can't be used as a starting boundary key here.  The part of
+			 * the row comparison that we do still use has to be treated as a
+			 * ">=" or "<=" condition.  For example, a qual "(a, c) > (1, 42)"
+			 * with an omitted intervening index attribute "b" will use an
+			 * insertion scan key "a >= 1".  Even the first "a = 1" tuple on
+			 * the leaf level might satisfy the row compare qual.
+			 *
+			 * We're able to use a _more_ restrictive strategy when we reach a
+			 * NULL row compare member, since they're always unsatisfiable.
+			 * For example, a qual "(a, b, c) >= (1, NULL, 77)" will use an
+			 * insertion scan key "a > 1".  All tuples where "a = 1" cannot
+			 * possibly satisfy the row compare qual, so this is safe.
 			 */
-			if (i == keysz - 1)
+			Assert(!(subkey->sk_flags & SK_ROW_END));
+			for (;;)
 			{
-				bool		used_all_subkeys = false;
+				subkey++;
+				Assert(subkey->sk_flags & SK_ROW_MEMBER);
 
-				Assert(!(subkey->sk_flags & SK_ROW_END));
-				for (;;)
+				if (subkey->sk_flags & SK_ISNULL)
 				{
-					subkey++;
-					Assert(subkey->sk_flags & SK_ROW_MEMBER);
-					if (subkey->sk_attno != keysz + 1)
-						break;	/* out-of-sequence, can't use it */
-					if (subkey->sk_strategy != cur->sk_strategy)
-						break;	/* wrong direction, can't use it */
-					if (subkey->sk_flags & SK_ISNULL)
-						break;	/* can't use null keys */
-					Assert(keysz < INDEX_MAX_KEYS);
-					memcpy(inskey.scankeys + keysz, subkey,
-						   sizeof(ScanKeyData));
-					keysz++;
-					if (subkey->sk_flags & SK_ROW_END)
-					{
-						used_all_subkeys = true;
-						break;
-					}
+					/*
+					 * NULL member key, can only use earlier keys.
+					 *
+					 * We deliberately avoid checking if this key is marked
+					 * required.  All earlier keys are required, and this key
+					 * is unsatisfiable either way, so we can't miss anything.
+					 */
+					tighten_strat = true;
+					break;
 				}
-				if (!used_all_subkeys)
+
+				if (!(subkey->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD)))
 				{
-					switch (strat_total)
-					{
-						case BTLessStrategyNumber:
-							strat_total = BTLessEqualStrategyNumber;
-							break;
-						case BTGreaterStrategyNumber:
-							strat_total = BTGreaterEqualStrategyNumber;
-							break;
-					}
+					/* nonrequired member key, can only use earlier keys */
+					loosen_strat = true;
+					break;
 				}
-				break;			/* done with outer loop */
+
+				Assert(subkey->sk_attno == keysz + 1);
+				Assert(subkey->sk_strategy == bkey->sk_strategy);
+				Assert(keysz < INDEX_MAX_KEYS);
+
+				memcpy(inskey.scankeys + keysz, subkey,
+					   sizeof(ScanKeyData));
+				keysz++;
+				if (subkey->sk_flags & SK_ROW_END)
+					break;
 			}
-		}
-		else
-		{
-			/*
-			 * Ordinary comparison key.  Transform the search-style scan key
-			 * to an insertion scan key by replacing the sk_func with the
-			 * appropriate btree comparison function.
-			 *
-			 * If scankey operator is not a cross-type comparison, we can use
-			 * the cached comparison function; otherwise gotta look it up in
-			 * the catalogs.  (That can't lead to infinite recursion, since no
-			 * indexscan initiated by syscache lookup will use cross-data-type
-			 * operators.)
-			 *
-			 * We support the convention that sk_subtype == InvalidOid means
-			 * the opclass input type; this is a hack to simplify life for
-			 * ScanKeyInit().
-			 */
-			if (cur->sk_subtype == rel->rd_opcintype[i] ||
-				cur->sk_subtype == InvalidOid)
+			Assert(!(loosen_strat && tighten_strat));
+			if (loosen_strat)
 			{
-				FmgrInfo   *procinfo;
-
-				procinfo = index_getprocinfo(rel, cur->sk_attno, BTORDER_PROC);
-				ScanKeyEntryInitializeWithInfo(inskey.scankeys + i,
-											   cur->sk_flags,
-											   cur->sk_attno,
-											   InvalidStrategy,
-											   cur->sk_subtype,
-											   cur->sk_collation,
-											   procinfo,
-											   cur->sk_argument);
+				/* Use less restrictive strategy (and fewer member keys) */
+				switch (strat_total)
+				{
+					case BTLessStrategyNumber:
+						strat_total = BTLessEqualStrategyNumber;
+						break;
+					case BTGreaterStrategyNumber:
+						strat_total = BTGreaterEqualStrategyNumber;
+						break;
+				}
 			}
-			else
+			if (tighten_strat)
 			{
-				RegProcedure cmp_proc;
-
-				cmp_proc = get_opfamily_proc(rel->rd_opfamily[i],
-											 rel->rd_opcintype[i],
-											 cur->sk_subtype,
-											 BTORDER_PROC);
-				if (!RegProcedureIsValid(cmp_proc))
-					elog(ERROR, "missing support function %d(%u,%u) for attribute %d of index \"%s\"",
-						 BTORDER_PROC, rel->rd_opcintype[i], cur->sk_subtype,
-						 cur->sk_attno, RelationGetRelationName(rel));
-				ScanKeyEntryInitialize(inskey.scankeys + i,
-									   cur->sk_flags,
-									   cur->sk_attno,
-									   InvalidStrategy,
-									   cur->sk_subtype,
-									   cur->sk_collation,
-									   cmp_proc,
-									   cur->sk_argument);
+				/* Use more restrictive strategy (and fewer member keys) */
+				switch (strat_total)
+				{
+					case BTLessEqualStrategyNumber:
+						strat_total = BTLessStrategyNumber;
+						break;
+					case BTGreaterEqualStrategyNumber:
+						strat_total = BTGreaterStrategyNumber;
+						break;
+				}
 			}
+
+			/* done adding to inskey (row comparison keys always come last) */
+			break;
+		}
+
+		/*
+		 * Ordinary comparison key/search-style key.
+		 *
+		 * Transform the search-style scan key to an insertion scan key by
+		 * replacing the sk_func with the appropriate btree 3-way-comparison
+		 * function.
+		 *
+		 * If scankey operator is not a cross-type comparison, we can use the
+		 * cached comparison function; otherwise gotta look it up in the
+		 * catalogs.  (That can't lead to infinite recursion, since no
+		 * indexscan initiated by syscache lookup will use cross-data-type
+		 * operators.)
+		 *
+		 * We support the convention that sk_subtype == InvalidOid means the
+		 * opclass input type; this hack simplifies life for ScanKeyInit().
+		 */
+		if (bkey->sk_subtype == rel->rd_opcintype[i] ||
+			bkey->sk_subtype == InvalidOid)
+		{
+			FmgrInfo   *procinfo;
+
+			procinfo = index_getprocinfo(rel, bkey->sk_attno, BTORDER_PROC);
+			ScanKeyEntryInitializeWithInfo(inskey.scankeys + i,
+										   bkey->sk_flags,
+										   bkey->sk_attno,
+										   InvalidStrategy,
+										   bkey->sk_subtype,
+										   bkey->sk_collation,
+										   procinfo,
+										   bkey->sk_argument);
+		}
+		else
+		{
+			RegProcedure cmp_proc;
+
+			cmp_proc = get_opfamily_proc(rel->rd_opfamily[i],
+										 rel->rd_opcintype[i],
+										 bkey->sk_subtype, BTORDER_PROC);
+			if (!RegProcedureIsValid(cmp_proc))
+				elog(ERROR, "missing support function %d(%u,%u) for attribute %d of index \"%s\"",
+					 BTORDER_PROC, rel->rd_opcintype[i], bkey->sk_subtype,
+					 bkey->sk_attno, RelationGetRelationName(rel));
+			ScanKeyEntryInitialize(inskey.scankeys + i,
+								   bkey->sk_flags,
+								   bkey->sk_attno,
+								   InvalidStrategy,
+								   bkey->sk_subtype,
+								   bkey->sk_collation,
+								   cmp_proc,
+								   bkey->sk_argument);
 		}
 	}
 
@@ -1474,6 +1520,8 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
 
 	if (!BufferIsValid(so->currPos.buf))
 	{
+		Assert(!so->needPrimScan);
+
 		/*
 		 * We only get here if the index is completely empty. Lock relation
 		 * because nothing finer to lock exists.  Without a buffer lock, it's
@@ -1492,7 +1540,6 @@ _bt_first(IndexScanDesc scan, ScanDirection dir)
 
 		if (!BufferIsValid(so->currPos.buf))
 		{
-			Assert(!so->needPrimScan);
 			_bt_parallel_done(scan);
 			return false;
 		}
diff --git a/src/backend/access/nbtree/nbtutils.c b/src/backend/access/nbtree/nbtutils.c
index c71d1b6f2e1e0..9aed207995f52 100644
--- a/src/backend/access/nbtree/nbtutils.c
+++ b/src/backend/access/nbtree/nbtutils.c
@@ -44,7 +44,6 @@ static bool _bt_array_decrement(Relation rel, ScanKey skey, BTArrayKeyInfo *arra
 static bool _bt_array_increment(Relation rel, ScanKey skey, BTArrayKeyInfo *array);
 static bool _bt_advance_array_keys_increment(IndexScanDesc scan, ScanDirection dir,
 											 bool *skip_array_set);
-static void _bt_rewind_nonrequired_arrays(IndexScanDesc scan, ScanDirection dir);
 static bool _bt_tuple_before_array_skeys(IndexScanDesc scan, ScanDirection dir,
 										 IndexTuple tuple, TupleDesc tupdesc, int tupnatts,
 										 bool readpagetup, int sktrig, bool *scanBehind);
@@ -52,7 +51,6 @@ static bool _bt_advance_array_keys(IndexScanDesc scan, BTReadPageState *pstate,
 								   IndexTuple tuple, int tupnatts, TupleDesc tupdesc,
 								   int sktrig, bool sktrig_required);
 #ifdef USE_ASSERT_CHECKING
-static bool _bt_verify_arrays_bt_first(IndexScanDesc scan, ScanDirection dir);
 static bool _bt_verify_keys_with_arraykeys(IndexScanDesc scan);
 #endif
 static bool _bt_oppodir_checkkeys(IndexScanDesc scan, ScanDirection dir,
@@ -1034,73 +1032,6 @@ _bt_advance_array_keys_increment(IndexScanDesc scan, ScanDirection dir,
 	return false;
 }
 
-/*
- * _bt_rewind_nonrequired_arrays() -- Rewind SAOP arrays not marked required
- *
- * Called when _bt_advance_array_keys decides to start a new primitive index
- * scan on the basis of the current scan position being before the position
- * that _bt_first is capable of repositioning the scan to by applying an
- * inequality operator required in the opposite-to-scan direction only.
- *
- * Although equality strategy scan keys (for both arrays and non-arrays alike)
- * are either marked required in both directions or in neither direction,
- * there is a sense in which non-required arrays behave like required arrays.
- * With a qual such as "WHERE a IN (100, 200) AND b >= 3 AND c IN (5, 6, 7)",
- * the scan key on "c" is non-required, but nevertheless enables positioning
- * the scan at the first tuple >= "(100, 3, 5)" on the leaf level during the
- * first descent of the tree by _bt_first.  Later on, there could also be a
- * second descent, that places the scan right before tuples >= "(200, 3, 5)".
- * _bt_first must never be allowed to build an insertion scan key whose "c"
- * entry is set to a value other than 5, the "c" array's first element/value.
- * (Actually, it's the first in the current scan direction.  This example uses
- * a forward scan.)
- *
- * Calling here resets the array scan key elements for the scan's non-required
- * arrays.  This is strictly necessary for correctness in a subset of cases
- * involving "required in opposite direction"-triggered primitive index scans.
- * Not all callers are at risk of _bt_first using a non-required array like
- * this, but advancement always resets the arrays when another primitive scan
- * is scheduled, just to keep things simple.  Array advancement even makes
- * sure to reset non-required arrays during scans that have no inequalities.
- * (Advancement still won't call here when there are no inequalities, though
- * that's just because it's all handled indirectly instead.)
- *
- * Note: _bt_verify_arrays_bt_first is called by an assertion to enforce that
- * everybody got this right.
- *
- * Note: In practice almost all SAOP arrays are marked required during
- * preprocessing (if necessary by generating skip arrays).  It is hardly ever
- * truly necessary to call here, but consistently doing so is simpler.
- */
-static void
-_bt_rewind_nonrequired_arrays(IndexScanDesc scan, ScanDirection dir)
-{
-	Relation	rel = scan->indexRelation;
-	BTScanOpaque so = (BTScanOpaque) scan->opaque;
-	int			arrayidx = 0;
-
-	for (int ikey = 0; ikey < so->numberOfKeys; ikey++)
-	{
-		ScanKey		cur = so->keyData + ikey;
-		BTArrayKeyInfo *array = NULL;
-
-		if (!(cur->sk_flags & SK_SEARCHARRAY) ||
-			cur->sk_strategy != BTEqualStrategyNumber)
-			continue;
-
-		array = &so->arrayKeys[arrayidx++];
-		Assert(array->scan_key == ikey);
-
-		if ((cur->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD)))
-			continue;
-
-		Assert(array->num_elems != -1); /* No non-required skip arrays */
-
-		_bt_array_set_low_or_high(rel, cur, array,
-								  ScanDirectionIsForward(dir));
-	}
-}
-
 /*
  * _bt_tuple_before_array_skeys() -- too early to advance required arrays?
  *
@@ -1380,8 +1311,6 @@ _bt_start_prim_scan(IndexScanDesc scan, ScanDirection dir)
 	 */
 	if (so->needPrimScan)
 	{
-		Assert(_bt_verify_arrays_bt_first(scan, dir));
-
 		/*
 		 * Flag was set -- must call _bt_first again, which will reset the
 		 * scan's needPrimScan flag
@@ -2007,14 +1936,7 @@ _bt_advance_array_keys(IndexScanDesc scan, BTReadPageState *pstate,
 	 */
 	else if (has_required_opposite_direction_only && pstate->finaltup &&
 			 unlikely(!_bt_oppodir_checkkeys(scan, dir, pstate->finaltup)))
-	{
-		/*
-		 * Make sure that any SAOP arrays that were not marked required by
-		 * preprocessing are reset to their first element for this direction
-		 */
-		_bt_rewind_nonrequired_arrays(scan, dir);
 		goto new_prim_scan;
-	}
 
 continue_scan:
 
@@ -2045,8 +1967,6 @@ _bt_advance_array_keys(IndexScanDesc scan, BTReadPageState *pstate,
 		 */
 		so->oppositeDirCheck = has_required_opposite_direction_only;
 
-		_bt_rewind_nonrequired_arrays(scan, dir);
-
 		/*
 		 * skip by setting "look ahead" mechanism's offnum for forwards scans
 		 * (backwards scans check scanBehind flag directly instead)
@@ -2142,48 +2062,6 @@ _bt_advance_array_keys(IndexScanDesc scan, BTReadPageState *pstate,
 }
 
 #ifdef USE_ASSERT_CHECKING
-/*
- * Verify that the scan's qual state matches what we expect at the point that
- * _bt_start_prim_scan is about to start a just-scheduled new primitive scan.
- *
- * We enforce a rule against non-required array scan keys: they must start out
- * with whatever element is the first for the scan's current scan direction.
- * See _bt_rewind_nonrequired_arrays comments for an explanation.
- */
-static bool
-_bt_verify_arrays_bt_first(IndexScanDesc scan, ScanDirection dir)
-{
-	BTScanOpaque so = (BTScanOpaque) scan->opaque;
-	int			arrayidx = 0;
-
-	for (int ikey = 0; ikey < so->numberOfKeys; ikey++)
-	{
-		ScanKey		cur = so->keyData + ikey;
-		BTArrayKeyInfo *array = NULL;
-		int			first_elem_dir;
-
-		if (!(cur->sk_flags & SK_SEARCHARRAY) ||
-			cur->sk_strategy != BTEqualStrategyNumber)
-			continue;
-
-		array = &so->arrayKeys[arrayidx++];
-
-		if (((cur->sk_flags & SK_BT_REQFWD) && ScanDirectionIsForward(dir)) ||
-			((cur->sk_flags & SK_BT_REQBKWD) && ScanDirectionIsBackward(dir)))
-			continue;
-
-		if (ScanDirectionIsForward(dir))
-			first_elem_dir = 0;
-		else
-			first_elem_dir = array->num_elems - 1;
-
-		if (array->cur_elem != first_elem_dir)
-			return false;
-	}
-
-	return _bt_verify_keys_with_arraykeys(scan);
-}
-
 /*
  * Verify that the scan's "so->keyData[]" scan keys are in agreement with
  * its array key state
@@ -2194,6 +2072,7 @@ _bt_verify_keys_with_arraykeys(IndexScanDesc scan)
 	BTScanOpaque so = (BTScanOpaque) scan->opaque;
 	int			last_sk_attno = InvalidAttrNumber,
 				arrayidx = 0;
+	bool		nonrequiredseen = false;
 
 	if (!so->qual_ok)
 		return false;
@@ -2217,8 +2096,16 @@ _bt_verify_keys_with_arraykeys(IndexScanDesc scan)
 		if (array->num_elems != -1 &&
 			cur->sk_argument != array->elem_values[array->cur_elem])
 			return false;
-		if (last_sk_attno > cur->sk_attno)
-			return false;
+		if (cur->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD))
+		{
+			if (last_sk_attno > cur->sk_attno)
+				return false;
+			if (nonrequiredseen)
+				return false;
+		}
+		else
+			nonrequiredseen = true;
+
 		last_sk_attno = cur->sk_attno;
 	}
 
@@ -2551,37 +2438,12 @@ _bt_set_startikey(IndexScanDesc scan, BTReadPageState *pstate)
 		if (!(key->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD)))
 		{
 			/* Scan key isn't marked required (corner case) */
-			Assert(!(key->sk_flags & SK_ROW_HEADER));
 			break;				/* unsafe */
 		}
 		if (key->sk_flags & SK_ROW_HEADER)
 		{
-			/*
-			 * RowCompare inequality.
-			 *
-			 * Only the first subkey from a RowCompare can ever be marked
-			 * required (that happens when the row header is marked required).
-			 * There is no simple, general way for us to transitively deduce
-			 * whether or not every tuple on the page satisfies a RowCompare
-			 * key based only on firsttup and lasttup -- so we just give up.
-			 */
-			if (!start_past_saop_eq && !so->skipScan)
-				break;			/* unsafe to go further */
-
-			/*
-			 * We have to be even more careful with RowCompares that come
-			 * after an array: we assume it's unsafe to even bypass the array.
-			 * Calling _bt_start_array_keys to recover the scan's arrays
-			 * following use of forcenonrequired mode isn't compatible with
-			 * _bt_check_rowcompare's continuescan=false behavior with NULL
-			 * row compare members.  _bt_advance_array_keys must not make a
-			 * decision on the basis of a key not being satisfied in the
-			 * opposite-to-scan direction until the scan reaches a leaf page
-			 * where the same key begins to be satisfied in scan direction.
-			 * The _bt_first !used_all_subkeys behavior makes this limitation
-			 * hard to work around some other way.
-			 */
-			return;				/* completely unsafe to set pstate.startikey */
+			/* RowCompare inequalities currently aren't supported */
+			break;				/* "unsafe" */
 		}
 		if (key->sk_strategy != BTEqualStrategyNumber)
 		{
@@ -3078,6 +2940,31 @@ _bt_check_rowcompare(ScanKey skey, IndexTuple tuple, int tupnatts,
 
 		Assert(subkey->sk_flags & SK_ROW_MEMBER);
 
+		/* When a NULL row member is compared, the row never matches */
+		if (subkey->sk_flags & SK_ISNULL)
+		{
+			/*
+			 * Unlike the simple-scankey case, this isn't a disallowed case
+			 * (except when it's the first row element that has the NULL arg).
+			 * But it can never match.  If all the earlier row comparison
+			 * columns are required for the scan direction, we can stop the
+			 * scan, because there can't be another tuple that will succeed.
+			 */
+			Assert(subkey != (ScanKey) DatumGetPointer(skey->sk_argument));
+			subkey--;
+			if (forcenonrequired)
+			{
+				/* treating scan's keys as non-required */
+			}
+			else if ((subkey->sk_flags & SK_BT_REQFWD) &&
+					 ScanDirectionIsForward(dir))
+				*continuescan = false;
+			else if ((subkey->sk_flags & SK_BT_REQBKWD) &&
+					 ScanDirectionIsBackward(dir))
+				*continuescan = false;
+			return false;
+		}
+
 		if (subkey->sk_attno > tupnatts)
 		{
 			/*
@@ -3087,11 +2974,7 @@ _bt_check_rowcompare(ScanKey skey, IndexTuple tuple, int tupnatts,
 			 * attribute passes the qual.
 			 */
 			Assert(BTreeTupleIsPivot(tuple));
-			cmpresult = 0;
-			if (subkey->sk_flags & SK_ROW_END)
-				break;
-			subkey++;
-			continue;
+			return true;
 		}
 
 		datum = index_getattr(tuple,
@@ -3101,6 +2984,8 @@ _bt_check_rowcompare(ScanKey skey, IndexTuple tuple, int tupnatts,
 
 		if (isNull)
 		{
+			int			reqflags;
+
 			if (forcenonrequired)
 			{
 				/* treating scan's keys as non-required */
@@ -3111,15 +2996,35 @@ _bt_check_rowcompare(ScanKey skey, IndexTuple tuple, int tupnatts,
 				 * Since NULLs are sorted before non-NULLs, we know we have
 				 * reached the lower limit of the range of values for this
 				 * index attr.  On a backward scan, we can stop if this qual
-				 * is one of the "must match" subset.  We can stop regardless
-				 * of whether the qual is > or <, so long as it's required,
-				 * because it's not possible for any future tuples to pass. On
-				 * a forward scan, however, we must keep going, because we may
-				 * have initially positioned to the start of the index.
-				 * (_bt_advance_array_keys also relies on this behavior during
-				 * forward scans.)
+				 * is one of the "must match" subset.  However, on a forwards
+				 * scan, we must keep going, because we may have initially
+				 * positioned to the start of the index.
+				 *
+				 * All required NULLS FIRST > row members can use NULL tuple
+				 * values to end backwards scans, just like with other values.
+				 * A qual "WHERE (a, b, c) > (9, 42, 'foo')" can terminate a
+				 * backwards scan upon reaching the index's rightmost "a = 9"
+				 * tuple whose "b" column contains a NULL (if not sooner).
+				 * Since "b" is NULLS FIRST, we can treat its NULLs as "<" 42.
+				 */
+				reqflags = SK_BT_REQBKWD;
+
+				/*
+				 * When a most significant required NULLS FIRST < row compare
+				 * member sees NULL tuple values during a backwards scan, it
+				 * signals the end of matches for the whole row compare/scan.
+				 * A qual "WHERE (a, b, c) < (9, 42, 'foo')" will terminate a
+				 * backwards scan upon reaching the rightmost tuple whose "a"
+				 * column has a NULL.  The "a" NULL value is "<" 9, and yet
+				 * our < row compare will still end the scan.  (This isn't
+				 * safe with later/lower-order row members.  Notice that it
+				 * can only happen with an "a" NULL some time after the scan
+				 * completely stops needing to use its "b" and "c" members.)
 				 */
-				if ((subkey->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD)) &&
+				if (subkey == (ScanKey) DatumGetPointer(skey->sk_argument))
+					reqflags |= SK_BT_REQFWD;	/* safe, first row member */
+
+				if ((subkey->sk_flags & reqflags) &&
 					ScanDirectionIsBackward(dir))
 					*continuescan = false;
 			}
@@ -3129,15 +3034,35 @@ _bt_check_rowcompare(ScanKey skey, IndexTuple tuple, int tupnatts,
 				 * Since NULLs are sorted after non-NULLs, we know we have
 				 * reached the upper limit of the range of values for this
 				 * index attr.  On a forward scan, we can stop if this qual is
-				 * one of the "must match" subset.  We can stop regardless of
-				 * whether the qual is > or <, so long as it's required,
-				 * because it's not possible for any future tuples to pass. On
-				 * a backward scan, however, we must keep going, because we
-				 * may have initially positioned to the end of the index.
-				 * (_bt_advance_array_keys also relies on this behavior during
-				 * backward scans.)
+				 * one of the "must match" subset.  However, on a backward
+				 * scan, we must keep going, because we may have initially
+				 * positioned to the end of the index.
+				 *
+				 * All required NULLS LAST < row members can use NULL tuple
+				 * values to end forwards scans, just like with other values.
+				 * A qual "WHERE (a, b, c) < (9, 42, 'foo')" can terminate a
+				 * forwards scan upon reaching the index's leftmost "a = 9"
+				 * tuple whose "b" column contains a NULL (if not sooner).
+				 * Since "b" is NULLS LAST, we can treat its NULLs as ">" 42.
 				 */
-				if ((subkey->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD)) &&
+				reqflags = SK_BT_REQFWD;
+
+				/*
+				 * When a most significant required NULLS LAST > row compare
+				 * member sees NULL tuple values during a forwards scan, it
+				 * signals the end of matches for the whole row compare/scan.
+				 * A qual "WHERE (a, b, c) > (9, 42, 'foo')" will terminate a
+				 * forwards scan upon reaching the leftmost tuple whose "a"
+				 * column has a NULL.  The "a" NULL value is ">" 9, and yet
+				 * our > row compare will end the scan.  (This isn't safe with
+				 * later/lower-order row members.  Notice that it can only
+				 * happen with an "a" NULL some time after the scan completely
+				 * stops needing to use its "b" and "c" members.)
+				 */
+				if (subkey == (ScanKey) DatumGetPointer(skey->sk_argument))
+					reqflags |= SK_BT_REQBKWD;	/* safe, first row member */
+
+				if ((subkey->sk_flags & reqflags) &&
 					ScanDirectionIsForward(dir))
 					*continuescan = false;
 			}
@@ -3148,30 +3073,6 @@ _bt_check_rowcompare(ScanKey skey, IndexTuple tuple, int tupnatts,
 			return false;
 		}
 
-		if (subkey->sk_flags & SK_ISNULL)
-		{
-			/*
-			 * Unlike the simple-scankey case, this isn't a disallowed case
-			 * (except when it's the first row element that has the NULL arg).
-			 * But it can never match.  If all the earlier row comparison
-			 * columns are required for the scan direction, we can stop the
-			 * scan, because there can't be another tuple that will succeed.
-			 */
-			Assert(subkey != (ScanKey) DatumGetPointer(skey->sk_argument));
-			subkey--;
-			if (forcenonrequired)
-			{
-				/* treating scan's keys as non-required */
-			}
-			else if ((subkey->sk_flags & SK_BT_REQFWD) &&
-					 ScanDirectionIsForward(dir))
-				*continuescan = false;
-			else if ((subkey->sk_flags & SK_BT_REQBKWD) &&
-					 ScanDirectionIsBackward(dir))
-				*continuescan = false;
-			return false;
-		}
-
 		/* Perform the test --- three-way comparison not bool operator */
 		cmpresult = DatumGetInt32(FunctionCall2Coll(&subkey->sk_func,
 													subkey->sk_collation,
diff --git a/src/backend/access/rmgrdesc/replorigindesc.c b/src/backend/access/rmgrdesc/replorigindesc.c
index 5dd742339969a..35e3af2903ed2 100644
--- a/src/backend/access/rmgrdesc/replorigindesc.c
+++ b/src/backend/access/rmgrdesc/replorigindesc.c
@@ -29,7 +29,7 @@ replorigin_desc(StringInfo buf, XLogReaderState *record)
 
 				xlrec = (xl_replorigin_set *) rec;
 
-				appendStringInfo(buf, "set %u; lsn %X/%X; force: %d",
+				appendStringInfo(buf, "set %u; lsn %X/%08X; force: %d",
 								 xlrec->node_id,
 								 LSN_FORMAT_ARGS(xlrec->remote_lsn),
 								 xlrec->force);
diff --git a/src/backend/access/rmgrdesc/xactdesc.c b/src/backend/access/rmgrdesc/xactdesc.c
index 305598e2865c8..f0f696855b9af 100644
--- a/src/backend/access/rmgrdesc/xactdesc.c
+++ b/src/backend/access/rmgrdesc/xactdesc.c
@@ -359,7 +359,7 @@ xact_desc_commit(StringInfo buf, uint8 info, xl_xact_commit *xlrec, RepOriginId
 
 	if (parsed.xinfo & XACT_XINFO_HAS_ORIGIN)
 	{
-		appendStringInfo(buf, "; origin: node %u, lsn %X/%X, at %s",
+		appendStringInfo(buf, "; origin: node %u, lsn %X/%08X, at %s",
 						 origin_id,
 						 LSN_FORMAT_ARGS(parsed.origin_lsn),
 						 timestamptz_to_str(parsed.origin_timestamp));
@@ -384,7 +384,7 @@ xact_desc_abort(StringInfo buf, uint8 info, xl_xact_abort *xlrec, RepOriginId or
 
 	if (parsed.xinfo & XACT_XINFO_HAS_ORIGIN)
 	{
-		appendStringInfo(buf, "; origin: node %u, lsn %X/%X, at %s",
+		appendStringInfo(buf, "; origin: node %u, lsn %X/%08X, at %s",
 						 origin_id,
 						 LSN_FORMAT_ARGS(parsed.origin_lsn),
 						 timestamptz_to_str(parsed.origin_timestamp));
@@ -418,7 +418,7 @@ xact_desc_prepare(StringInfo buf, uint8 info, xl_xact_prepare *xlrec, RepOriginI
 	 * way as PrepareRedoAdd().
 	 */
 	if (origin_id != InvalidRepOriginId)
-		appendStringInfo(buf, "; origin: node %u, lsn %X/%X, at %s",
+		appendStringInfo(buf, "; origin: node %u, lsn %X/%08X, at %s",
 						 origin_id,
 						 LSN_FORMAT_ARGS(parsed.origin_lsn),
 						 timestamptz_to_str(parsed.origin_timestamp));
diff --git a/src/backend/access/rmgrdesc/xlogdesc.c b/src/backend/access/rmgrdesc/xlogdesc.c
index 58040f28656fc..cd6c2a2f650a6 100644
--- a/src/backend/access/rmgrdesc/xlogdesc.c
+++ b/src/backend/access/rmgrdesc/xlogdesc.c
@@ -65,7 +65,7 @@ xlog_desc(StringInfo buf, XLogReaderState *record)
 	{
 		CheckPoint *checkpoint = (CheckPoint *) rec;
 
-		appendStringInfo(buf, "redo %X/%X; "
+		appendStringInfo(buf, "redo %X/%08X; "
 						 "tli %u; prev tli %u; fpw %s; wal_level %s; xid %u:%u; oid %u; multi %u; offset %u; "
 						 "oldest xid %u in DB %u; oldest multi %u in DB %u; "
 						 "oldest/newest commit timestamp xid: %u/%u; "
@@ -111,7 +111,7 @@ xlog_desc(StringInfo buf, XLogReaderState *record)
 		XLogRecPtr	startpoint;
 
 		memcpy(&startpoint, rec, sizeof(XLogRecPtr));
-		appendStringInfo(buf, "%X/%X", LSN_FORMAT_ARGS(startpoint));
+		appendStringInfo(buf, "%X/%08X", LSN_FORMAT_ARGS(startpoint));
 	}
 	else if (info == XLOG_PARAMETER_CHANGE)
 	{
@@ -156,7 +156,7 @@ xlog_desc(StringInfo buf, XLogReaderState *record)
 		xl_overwrite_contrecord xlrec;
 
 		memcpy(&xlrec, rec, sizeof(xl_overwrite_contrecord));
-		appendStringInfo(buf, "lsn %X/%X; time %s",
+		appendStringInfo(buf, "lsn %X/%08X; time %s",
 						 LSN_FORMAT_ARGS(xlrec.overwritten_lsn),
 						 timestamptz_to_str(xlrec.overwrite_time));
 	}
diff --git a/src/backend/access/spgist/spgutils.c b/src/backend/access/spgist/spgutils.c
index 95fea74e296f8..9b86c016acb37 100644
--- a/src/backend/access/spgist/spgutils.c
+++ b/src/backend/access/spgist/spgutils.c
@@ -785,7 +785,7 @@ SpGistGetInnerTypeSize(SpGistTypeDesc *att, Datum datum)
 	else if (att->attlen > 0)
 		size = att->attlen;
 	else
-		size = VARSIZE_ANY(datum);
+		size = VARSIZE_ANY(DatumGetPointer(datum));
 
 	return MAXALIGN(size);
 }
@@ -804,7 +804,7 @@ memcpyInnerDatum(void *target, SpGistTypeDesc *att, Datum datum)
 	}
 	else
 	{
-		size = (att->attlen > 0) ? att->attlen : VARSIZE_ANY(datum);
+		size = (att->attlen > 0) ? att->attlen : VARSIZE_ANY(DatumGetPointer(datum));
 		memcpy(target, DatumGetPointer(datum), size);
 	}
 }
diff --git a/src/backend/access/table/toast_helper.c b/src/backend/access/table/toast_helper.c
index b60fab0a4d294..11f97d65367d5 100644
--- a/src/backend/access/table/toast_helper.c
+++ b/src/backend/access/table/toast_helper.c
@@ -330,7 +330,7 @@ toast_delete_external(Relation rel, const Datum *values, const bool *isnull,
 
 			if (isnull[i])
 				continue;
-			else if (VARATT_IS_EXTERNAL_ONDISK(value))
+			else if (VARATT_IS_EXTERNAL_ONDISK(DatumGetPointer(value)))
 				toast_delete_datum(rel, value, is_speculative);
 		}
 	}
diff --git a/src/backend/access/transam/clog.c b/src/backend/access/transam/clog.c
index 48f10bec91e12..e80fbe109cf3c 100644
--- a/src/backend/access/transam/clog.c
+++ b/src/backend/access/transam/clog.c
@@ -110,9 +110,7 @@ static SlruCtlData XactCtlData;
 #define XactCtl (&XactCtlData)
 
 
-static int	ZeroCLOGPage(int64 pageno, bool writeXlog);
 static bool CLOGPagePrecedes(int64 page1, int64 page2);
-static void WriteZeroPageXlogRec(int64 pageno);
 static void WriteTruncateXlogRec(int64 pageno, TransactionId oldestXact,
 								 Oid oldestXactDb);
 static void TransactionIdSetPageStatus(TransactionId xid, int nsubxids,
@@ -832,41 +830,8 @@ check_transaction_buffers(int *newval, void **extra, GucSource source)
 void
 BootStrapCLOG(void)
 {
-	int			slotno;
-	LWLock	   *lock = SimpleLruGetBankLock(XactCtl, 0);
-
-	LWLockAcquire(lock, LW_EXCLUSIVE);
-
-	/* Create and zero the first page of the commit log */
-	slotno = ZeroCLOGPage(0, false);
-
-	/* Make sure it's written out */
-	SimpleLruWritePage(XactCtl, slotno);
-	Assert(!XactCtl->shared->page_dirty[slotno]);
-
-	LWLockRelease(lock);
-}
-
-/*
- * Initialize (or reinitialize) a page of CLOG to zeroes.
- * If writeXlog is true, also emit an XLOG record saying we did this.
- *
- * The page is not actually written, just set up in shared memory.
- * The slot number of the new page is returned.
- *
- * Control lock must be held at entry, and will be held at exit.
- */
-static int
-ZeroCLOGPage(int64 pageno, bool writeXlog)
-{
-	int			slotno;
-
-	slotno = SimpleLruZeroPage(XactCtl, pageno);
-
-	if (writeXlog)
-		WriteZeroPageXlogRec(pageno);
-
-	return slotno;
+	/* Zero the initial page and flush it to disk */
+	SimpleLruZeroAndWritePage(XactCtl, 0);
 }
 
 /*
@@ -974,8 +939,9 @@ ExtendCLOG(TransactionId newestXact)
 
 	LWLockAcquire(lock, LW_EXCLUSIVE);
 
-	/* Zero the page and make an XLOG entry about it */
-	ZeroCLOGPage(pageno, true);
+	/* Zero the page and make a WAL entry about it */
+	SimpleLruZeroPage(XactCtl, pageno);
+	XLogSimpleInsertInt64(RM_CLOG_ID, CLOG_ZEROPAGE, pageno);
 
 	LWLockRelease(lock);
 }
@@ -1067,17 +1033,6 @@ CLOGPagePrecedes(int64 page1, int64 page2)
 }
 
 
-/*
- * Write a ZEROPAGE xlog record
- */
-static void
-WriteZeroPageXlogRec(int64 pageno)
-{
-	XLogBeginInsert();
-	XLogRegisterData(&pageno, sizeof(pageno));
-	(void) XLogInsert(RM_CLOG_ID, CLOG_ZEROPAGE);
-}
-
 /*
  * Write a TRUNCATE xlog record
  *
@@ -1114,19 +1069,9 @@ clog_redo(XLogReaderState *record)
 	if (info == CLOG_ZEROPAGE)
 	{
 		int64		pageno;
-		int			slotno;
-		LWLock	   *lock;
 
 		memcpy(&pageno, XLogRecGetData(record), sizeof(pageno));
-
-		lock = SimpleLruGetBankLock(XactCtl, pageno);
-		LWLockAcquire(lock, LW_EXCLUSIVE);
-
-		slotno = ZeroCLOGPage(pageno, false);
-		SimpleLruWritePage(XactCtl, slotno);
-		Assert(!XactCtl->shared->page_dirty[slotno]);
-
-		LWLockRelease(lock);
+		SimpleLruZeroAndWritePage(XactCtl, pageno);
 	}
 	else if (info == CLOG_TRUNCATE)
 	{
diff --git a/src/backend/access/transam/commit_ts.c b/src/backend/access/transam/commit_ts.c
index 113fae1437ad8..370b38e048b91 100644
--- a/src/backend/access/transam/commit_ts.c
+++ b/src/backend/access/transam/commit_ts.c
@@ -114,11 +114,9 @@ static void SetXidCommitTsInPage(TransactionId xid, int nsubxids,
 static void TransactionIdSetCommitTs(TransactionId xid, TimestampTz ts,
 									 RepOriginId nodeid, int slotno);
 static void error_commit_ts_disabled(void);
-static int	ZeroCommitTsPage(int64 pageno, bool writeXlog);
 static bool CommitTsPagePrecedes(int64 page1, int64 page2);
 static void ActivateCommitTs(void);
 static void DeactivateCommitTs(void);
-static void WriteZeroPageXlogRec(int64 pageno);
 static void WriteTruncateXlogRec(int64 pageno, TransactionId oldestXid);
 
 /*
@@ -602,28 +600,6 @@ BootStrapCommitTs(void)
 	 */
 }
 
-/*
- * Initialize (or reinitialize) a page of CommitTs to zeroes.
- * If writeXlog is true, also emit an XLOG record saying we did this.
- *
- * The page is not actually written, just set up in shared memory.
- * The slot number of the new page is returned.
- *
- * Control lock must be held at entry, and will be held at exit.
- */
-static int
-ZeroCommitTsPage(int64 pageno, bool writeXlog)
-{
-	int			slotno;
-
-	slotno = SimpleLruZeroPage(CommitTsCtl, pageno);
-
-	if (writeXlog)
-		WriteZeroPageXlogRec(pageno);
-
-	return slotno;
-}
-
 /*
  * This must be called ONCE during postmaster or standalone-backend startup,
  * after StartupXLOG has initialized TransamVariables->nextXid.
@@ -707,6 +683,13 @@ ActivateCommitTs(void)
 	TransactionId xid;
 	int64		pageno;
 
+	/*
+	 * During bootstrap, we should not register commit timestamps so skip the
+	 * activation in this case.
+	 */
+	if (IsBootstrapProcessingMode())
+		return;
+
 	/* If we've done this already, there's nothing to do */
 	LWLockAcquire(CommitTsLock, LW_EXCLUSIVE);
 	if (commitTsShared->commitTsActive)
@@ -747,16 +730,7 @@ ActivateCommitTs(void)
 
 	/* Create the current segment file, if necessary */
 	if (!SimpleLruDoesPhysicalPageExist(CommitTsCtl, pageno))
-	{
-		LWLock	   *lock = SimpleLruGetBankLock(CommitTsCtl, pageno);
-		int			slotno;
-
-		LWLockAcquire(lock, LW_EXCLUSIVE);
-		slotno = ZeroCommitTsPage(pageno, false);
-		SimpleLruWritePage(CommitTsCtl, slotno);
-		Assert(!CommitTsCtl->shared->page_dirty[slotno]);
-		LWLockRelease(lock);
-	}
+		SimpleLruZeroAndWritePage(CommitTsCtl, pageno);
 
 	/* Change the activation status in shared memory. */
 	LWLockAcquire(CommitTsLock, LW_EXCLUSIVE);
@@ -867,8 +841,12 @@ ExtendCommitTs(TransactionId newestXact)
 
 	LWLockAcquire(lock, LW_EXCLUSIVE);
 
-	/* Zero the page and make an XLOG entry about it */
-	ZeroCommitTsPage(pageno, !InRecovery);
+	/* Zero the page ... */
+	SimpleLruZeroPage(CommitTsCtl, pageno);
+
+	/* and make a WAL entry about that, unless we're in REDO */
+	if (!InRecovery)
+		XLogSimpleInsertInt64(RM_COMMIT_TS_ID, COMMIT_TS_ZEROPAGE, pageno);
 
 	LWLockRelease(lock);
 }
@@ -982,17 +960,6 @@ CommitTsPagePrecedes(int64 page1, int64 page2)
 }
 
 
-/*
- * Write a ZEROPAGE xlog record
- */
-static void
-WriteZeroPageXlogRec(int64 pageno)
-{
-	XLogBeginInsert();
-	XLogRegisterData(&pageno, sizeof(pageno));
-	(void) XLogInsert(RM_COMMIT_TS_ID, COMMIT_TS_ZEROPAGE);
-}
-
 /*
  * Write a TRUNCATE xlog record
  */
@@ -1023,19 +990,9 @@ commit_ts_redo(XLogReaderState *record)
 	if (info == COMMIT_TS_ZEROPAGE)
 	{
 		int64		pageno;
-		int			slotno;
-		LWLock	   *lock;
 
 		memcpy(&pageno, XLogRecGetData(record), sizeof(pageno));
-
-		lock = SimpleLruGetBankLock(CommitTsCtl, pageno);
-		LWLockAcquire(lock, LW_EXCLUSIVE);
-
-		slotno = ZeroCommitTsPage(pageno, false);
-		SimpleLruWritePage(CommitTsCtl, slotno);
-		Assert(!CommitTsCtl->shared->page_dirty[slotno]);
-
-		LWLockRelease(lock);
+		SimpleLruZeroAndWritePage(CommitTsCtl, pageno);
 	}
 	else if (info == COMMIT_TS_TRUNCATE)
 	{
diff --git a/src/backend/access/transam/multixact.c b/src/backend/access/transam/multixact.c
index 3c06ac45532f8..3cb09c3d5987c 100644
--- a/src/backend/access/transam/multixact.c
+++ b/src/backend/access/transam/multixact.c
@@ -401,8 +401,6 @@ static void mXactCachePut(MultiXactId multi, int nmembers,
 static char *mxstatus_to_string(MultiXactStatus status);
 
 /* management of SLRU infrastructure */
-static int	ZeroMultiXactOffsetPage(int64 pageno, bool writeXlog);
-static int	ZeroMultiXactMemberPage(int64 pageno, bool writeXlog);
 static bool MultiXactOffsetPagePrecedes(int64 page1, int64 page2);
 static bool MultiXactMemberPagePrecedes(int64 page1, int64 page2);
 static bool MultiXactOffsetPrecedes(MultiXactOffset offset1,
@@ -413,7 +411,6 @@ static bool MultiXactOffsetWouldWrap(MultiXactOffset boundary,
 									 MultiXactOffset start, uint32 distance);
 static bool SetOffsetVacuumLimit(bool is_startup);
 static bool find_multixact_start(MultiXactId multi, MultiXactOffset *result);
-static void WriteMZeroPageXlogRec(int64 pageno, uint8 info);
 static void WriteMTruncateXlogRec(Oid oldestMultiDB,
 								  MultiXactId startTruncOff,
 								  MultiXactId endTruncOff,
@@ -1847,7 +1844,7 @@ AtPrepare_MultiXact(void)
  *		Clean up after successful PREPARE TRANSACTION
  */
 void
-PostPrepare_MultiXact(TransactionId xid)
+PostPrepare_MultiXact(FullTransactionId fxid)
 {
 	MultiXactId myOldestMember;
 
@@ -1858,7 +1855,7 @@ PostPrepare_MultiXact(TransactionId xid)
 	myOldestMember = OldestMemberMXactId[MyProcNumber];
 	if (MultiXactIdIsValid(myOldestMember))
 	{
-		ProcNumber	dummyProcNumber = TwoPhaseGetDummyProcNumber(xid, false);
+		ProcNumber	dummyProcNumber = TwoPhaseGetDummyProcNumber(fxid, false);
 
 		/*
 		 * Even though storing MultiXactId is atomic, acquire lock to make
@@ -1896,10 +1893,10 @@ PostPrepare_MultiXact(TransactionId xid)
  *		Recover the state of a prepared transaction at startup
  */
 void
-multixact_twophase_recover(TransactionId xid, uint16 info,
+multixact_twophase_recover(FullTransactionId fxid, uint16 info,
 						   void *recdata, uint32 len)
 {
-	ProcNumber	dummyProcNumber = TwoPhaseGetDummyProcNumber(xid, false);
+	ProcNumber	dummyProcNumber = TwoPhaseGetDummyProcNumber(fxid, false);
 	MultiXactId oldestMember;
 
 	/*
@@ -1917,10 +1914,10 @@ multixact_twophase_recover(TransactionId xid, uint16 info,
  *		Similar to AtEOXact_MultiXact but for COMMIT PREPARED
  */
 void
-multixact_twophase_postcommit(TransactionId xid, uint16 info,
+multixact_twophase_postcommit(FullTransactionId fxid, uint16 info,
 							  void *recdata, uint32 len)
 {
-	ProcNumber	dummyProcNumber = TwoPhaseGetDummyProcNumber(xid, true);
+	ProcNumber	dummyProcNumber = TwoPhaseGetDummyProcNumber(fxid, true);
 
 	Assert(len == sizeof(MultiXactId));
 
@@ -1932,10 +1929,10 @@ multixact_twophase_postcommit(TransactionId xid, uint16 info,
  *		This is actually just the same as the COMMIT case.
  */
 void
-multixact_twophase_postabort(TransactionId xid, uint16 info,
+multixact_twophase_postabort(FullTransactionId fxid, uint16 info,
 							 void *recdata, uint32 len)
 {
-	multixact_twophase_postcommit(xid, info, recdata, len);
+	multixact_twophase_postcommit(fxid, info, recdata, len);
 }
 
 /*
@@ -2033,70 +2030,9 @@ check_multixact_member_buffers(int *newval, void **extra, GucSource source)
 void
 BootStrapMultiXact(void)
 {
-	int			slotno;
-	LWLock	   *lock;
-
-	lock = SimpleLruGetBankLock(MultiXactOffsetCtl, 0);
-	LWLockAcquire(lock, LW_EXCLUSIVE);
-
-	/* Create and zero the first page of the offsets log */
-	slotno = ZeroMultiXactOffsetPage(0, false);
-
-	/* Make sure it's written out */
-	SimpleLruWritePage(MultiXactOffsetCtl, slotno);
-	Assert(!MultiXactOffsetCtl->shared->page_dirty[slotno]);
-
-	LWLockRelease(lock);
-
-	lock = SimpleLruGetBankLock(MultiXactMemberCtl, 0);
-	LWLockAcquire(lock, LW_EXCLUSIVE);
-
-	/* Create and zero the first page of the members log */
-	slotno = ZeroMultiXactMemberPage(0, false);
-
-	/* Make sure it's written out */
-	SimpleLruWritePage(MultiXactMemberCtl, slotno);
-	Assert(!MultiXactMemberCtl->shared->page_dirty[slotno]);
-
-	LWLockRelease(lock);
-}
-
-/*
- * Initialize (or reinitialize) a page of MultiXactOffset to zeroes.
- * If writeXlog is true, also emit an XLOG record saying we did this.
- *
- * The page is not actually written, just set up in shared memory.
- * The slot number of the new page is returned.
- *
- * Control lock must be held at entry, and will be held at exit.
- */
-static int
-ZeroMultiXactOffsetPage(int64 pageno, bool writeXlog)
-{
-	int			slotno;
-
-	slotno = SimpleLruZeroPage(MultiXactOffsetCtl, pageno);
-
-	if (writeXlog)
-		WriteMZeroPageXlogRec(pageno, XLOG_MULTIXACT_ZERO_OFF_PAGE);
-
-	return slotno;
-}
-
-/*
- * Ditto, for MultiXactMember
- */
-static int
-ZeroMultiXactMemberPage(int64 pageno, bool writeXlog)
-{
-	int			slotno;
-
-	slotno = SimpleLruZeroPage(MultiXactMemberCtl, pageno);
-
-	if (writeXlog)
-		WriteMZeroPageXlogRec(pageno, XLOG_MULTIXACT_ZERO_MEM_PAGE);
-
-	return slotno;
+	/* Zero the initial pages and flush them to disk */
+	SimpleLruZeroAndWritePage(MultiXactOffsetCtl, 0);
+	SimpleLruZeroAndWritePage(MultiXactMemberCtl, 0);
 }
 
 /*
@@ -2134,7 +2070,7 @@ MaybeExtendOffsetSlru(void)
 		 * with creating a new segment file even if the page we're writing is
 		 * not the first in it, so this is enough.
 		 */
-		slotno = ZeroMultiXactOffsetPage(pageno, false);
+		slotno = SimpleLruZeroPage(MultiXactOffsetCtl, pageno);
 		SimpleLruWritePage(MultiXactOffsetCtl, slotno);
 	}
 
@@ -2568,8 +2504,10 @@ ExtendMultiXactOffset(MultiXactId multi)
 
 	LWLockAcquire(lock, LW_EXCLUSIVE);
 
-	/* Zero the page and make an XLOG entry about it */
-	ZeroMultiXactOffsetPage(pageno, true);
+	/* Zero the page and make a WAL entry about it */
+	SimpleLruZeroPage(MultiXactOffsetCtl, pageno);
+	XLogSimpleInsertInt64(RM_MULTIXACT_ID, XLOG_MULTIXACT_ZERO_OFF_PAGE,
+						  pageno);
 
 	LWLockRelease(lock);
 }
@@ -2611,8 +2549,10 @@ ExtendMultiXactMember(MultiXactOffset offset, int nmembers)
 
 			LWLockAcquire(lock, LW_EXCLUSIVE);
 
-			/* Zero the page and make an XLOG entry about it */
-			ZeroMultiXactMemberPage(pageno, true);
+			/* Zero the page and make a WAL entry about it */
+			SimpleLruZeroPage(MultiXactMemberCtl, pageno);
+			XLogSimpleInsertInt64(RM_MULTIXACT_ID,
+								  XLOG_MULTIXACT_ZERO_MEM_PAGE, pageno);
 
 			LWLockRelease(lock);
 		}
@@ -3347,18 +3287,6 @@ MultiXactOffsetPrecedes(MultiXactOffset offset1, MultiXactOffset offset2)
 	return (diff < 0);
 }
 
-/*
- * Write an xlog record reflecting the zeroing of either a MEMBERs or
- * OFFSETs page (info shows which)
- */
-static void
-WriteMZeroPageXlogRec(int64 pageno, uint8 info)
-{
-	XLogBeginInsert();
-	XLogRegisterData(&pageno, sizeof(pageno));
-	(void) XLogInsert(RM_MULTIXACT_ID, info);
-}
-
 /*
  * Write a TRUNCATE xlog record
  *
@@ -3401,36 +3329,16 @@ multixact_redo(XLogReaderState *record)
 	if (info == XLOG_MULTIXACT_ZERO_OFF_PAGE)
 	{
 		int64		pageno;
-		int			slotno;
-		LWLock	   *lock;
 
 		memcpy(&pageno, XLogRecGetData(record), sizeof(pageno));
-
-		lock = SimpleLruGetBankLock(MultiXactOffsetCtl, pageno);
-		LWLockAcquire(lock, LW_EXCLUSIVE);
-
-		slotno = ZeroMultiXactOffsetPage(pageno, false);
-		SimpleLruWritePage(MultiXactOffsetCtl, slotno);
-		Assert(!MultiXactOffsetCtl->shared->page_dirty[slotno]);
-
-		LWLockRelease(lock);
+		SimpleLruZeroAndWritePage(MultiXactOffsetCtl, pageno);
 	}
 	else if (info == XLOG_MULTIXACT_ZERO_MEM_PAGE)
 	{
 		int64		pageno;
-		int			slotno;
-		LWLock	   *lock;
 
 		memcpy(&pageno, XLogRecGetData(record), sizeof(pageno));
-
-		lock = SimpleLruGetBankLock(MultiXactMemberCtl, pageno);
-		LWLockAcquire(lock, LW_EXCLUSIVE);
-
-		slotno = ZeroMultiXactMemberPage(pageno, false);
-		SimpleLruWritePage(MultiXactMemberCtl, slotno);
-		Assert(!MultiXactMemberCtl->shared->page_dirty[slotno]);
-
-		LWLockRelease(lock);
+		SimpleLruZeroAndWritePage(MultiXactMemberCtl, pageno);
 	}
 	else if (info == XLOG_MULTIXACT_CREATE_ID)
 	{
diff --git a/src/backend/access/transam/slru.c b/src/backend/access/transam/slru.c
index fe56286d9a972..10ec259f38295 100644
--- a/src/backend/access/transam/slru.c
+++ b/src/backend/access/transam/slru.c
@@ -433,6 +433,31 @@ SimpleLruZeroLSNs(SlruCtl ctl, int slotno)
 			   shared->lsn_groups_per_page * sizeof(XLogRecPtr));
 }
 
+/*
+ * This is a convenience wrapper for the common case of zeroing a page and
+ * immediately flushing it to disk.
+ *
+ * Control lock is acquired and released here.
+ */
+void
+SimpleLruZeroAndWritePage(SlruCtl ctl, int64 pageno)
+{
+	int			slotno;
+	LWLock	   *lock;
+
+	lock = SimpleLruGetBankLock(ctl, pageno);
+	LWLockAcquire(lock, LW_EXCLUSIVE);
+
+	/* Create and zero the page */
+	slotno = SimpleLruZeroPage(ctl, pageno);
+
+	/* Make sure it's written out */
+	SimpleLruWritePage(ctl, slotno);
+	Assert(!ctl->shared->page_dirty[slotno]);
+
+	LWLockRelease(lock);
+}
+
 /*
  * Wait for any active I/O on a page slot to finish.  (This does not
  * guarantee that new I/O hasn't been started before we return, though.
diff --git a/src/backend/access/transam/subtrans.c b/src/backend/access/transam/subtrans.c
index 15153618fad16..09aace9e09f0e 100644
--- a/src/backend/access/transam/subtrans.c
+++ b/src/backend/access/transam/subtrans.c
@@ -74,7 +74,6 @@ static SlruCtlData SubTransCtlData;
 #define SubTransCtl  (&SubTransCtlData)
 
 
-static int	ZeroSUBTRANSPage(int64 pageno);
 static bool SubTransPagePrecedes(int64 page1, int64 page2);
 
 
@@ -269,33 +268,8 @@ check_subtrans_buffers(int *newval, void **extra, GucSource source)
 void
 BootStrapSUBTRANS(void)
 {
-	int			slotno;
-	LWLock	   *lock = SimpleLruGetBankLock(SubTransCtl, 0);
-
-	LWLockAcquire(lock, LW_EXCLUSIVE);
-
-	/* Create and zero the first page of the subtrans log */
-	slotno = ZeroSUBTRANSPage(0);
-
-	/* Make sure it's written out */
-	SimpleLruWritePage(SubTransCtl, slotno);
-	Assert(!SubTransCtl->shared->page_dirty[slotno]);
-
-	LWLockRelease(lock);
-}
-
-/*
- * Initialize (or reinitialize) a page of SUBTRANS to zeroes.
- *
- * The page is not actually written, just set up in shared memory.
- * The slot number of the new page is returned.
- *
- * Control lock must be held at entry, and will be held at exit.
- */
-static int
-ZeroSUBTRANSPage(int64 pageno)
-{
-	return SimpleLruZeroPage(SubTransCtl, pageno);
+	/* Zero the initial page and flush it to disk */
+	SimpleLruZeroAndWritePage(SubTransCtl, 0);
 }
 
 /*
@@ -335,7 +309,7 @@ StartupSUBTRANS(TransactionId oldestActiveXID)
 			prevlock = lock;
 		}
 
-		(void) ZeroSUBTRANSPage(startPage);
+		(void) SimpleLruZeroPage(SubTransCtl, startPage);
 		if (startPage == endPage)
 			break;
 
@@ -395,7 +369,7 @@ ExtendSUBTRANS(TransactionId newestXact)
 	LWLockAcquire(lock, LW_EXCLUSIVE);
 
 	/* Zero the page */
-	ZeroSUBTRANSPage(pageno);
+	SimpleLruZeroPage(SubTransCtl, pageno);
 
 	LWLockRelease(lock);
 }
diff --git a/src/backend/access/transam/timeline.c b/src/backend/access/transam/timeline.c
index a27f27cc037d1..186eb91f60943 100644
--- a/src/backend/access/transam/timeline.c
+++ b/src/backend/access/transam/timeline.c
@@ -154,7 +154,7 @@ readTimeLineHistory(TimeLineID targetTLI)
 		if (*ptr == '\0' || *ptr == '#')
 			continue;
 
-		nfields = sscanf(fline, "%u\t%X/%X", &tli, &switchpoint_hi, &switchpoint_lo);
+		nfields = sscanf(fline, "%u\t%X/%08X", &tli, &switchpoint_hi, &switchpoint_lo);
 
 		if (nfields < 1)
 		{
@@ -399,7 +399,7 @@ writeTimeLineHistory(TimeLineID newTLI, TimeLineID parentTLI,
 	 * parent file failed to end with one.
 	 */
 	snprintf(buffer, sizeof(buffer),
-			 "%s%u\t%X/%X\t%s\n",
+			 "%s%u\t%X/%08X\t%s\n",
 			 (srcfd < 0) ? "" : "\n",
 			 parentTLI,
 			 LSN_FORMAT_ARGS(switchpoint),
diff --git a/src/backend/access/transam/twophase.c b/src/backend/access/transam/twophase.c
index 73a80559194e7..7918176fc588e 100644
--- a/src/backend/access/transam/twophase.c
+++ b/src/backend/access/transam/twophase.c
@@ -159,7 +159,7 @@ typedef struct GlobalTransactionData
 	 */
 	XLogRecPtr	prepare_start_lsn;	/* XLOG offset of prepare record start */
 	XLogRecPtr	prepare_end_lsn;	/* XLOG offset of prepare record end */
-	TransactionId xid;			/* The GXACT id */
+	FullTransactionId fxid;		/* The GXACT full xid */
 
 	Oid			owner;			/* ID of user that executed the xact */
 	ProcNumber	locking_backend;	/* backend currently working on the xact */
@@ -197,6 +197,7 @@ static GlobalTransaction MyLockedGxact = NULL;
 
 static bool twophaseExitRegistered = false;
 
+static void PrepareRedoRemoveFull(FullTransactionId fxid, bool giveWarning);
 static void RecordTransactionCommitPrepared(TransactionId xid,
 											int nchildren,
 											TransactionId *children,
@@ -216,19 +217,19 @@ static void RecordTransactionAbortPrepared(TransactionId xid,
 										   int nstats,
 										   xl_xact_stats_item *stats,
 										   const char *gid);
-static void ProcessRecords(char *bufptr, TransactionId xid,
+static void ProcessRecords(char *bufptr, FullTransactionId fxid,
 						   const TwoPhaseCallback callbacks[]);
 static void RemoveGXact(GlobalTransaction gxact);
 
 static void XlogReadTwoPhaseData(XLogRecPtr lsn, char **buf, int *len);
-static char *ProcessTwoPhaseBuffer(TransactionId xid,
+static char *ProcessTwoPhaseBuffer(FullTransactionId fxid,
 								   XLogRecPtr prepare_start_lsn,
 								   bool fromdisk, bool setParent, bool setNextXid);
-static void MarkAsPreparingGuts(GlobalTransaction gxact, TransactionId xid,
+static void MarkAsPreparingGuts(GlobalTransaction gxact, FullTransactionId fxid,
 								const char *gid, TimestampTz prepared_at, Oid owner,
 								Oid databaseid);
-static void RemoveTwoPhaseFile(TransactionId xid, bool giveWarning);
-static void RecreateTwoPhaseFile(TransactionId xid, void *content, int len);
+static void RemoveTwoPhaseFile(FullTransactionId fxid, bool giveWarning);
+static void RecreateTwoPhaseFile(FullTransactionId fxid, void *content, int len);
 
 /*
  * Initialization of shared memory
@@ -356,7 +357,7 @@ PostPrepare_Twophase(void)
  *		Reserve the GID for the given transaction.
  */
 GlobalTransaction
-MarkAsPreparing(TransactionId xid, const char *gid,
+MarkAsPreparing(FullTransactionId fxid, const char *gid,
 				TimestampTz prepared_at, Oid owner, Oid databaseid)
 {
 	GlobalTransaction gxact;
@@ -407,7 +408,7 @@ MarkAsPreparing(TransactionId xid, const char *gid,
 	gxact = TwoPhaseState->freeGXacts;
 	TwoPhaseState->freeGXacts = gxact->next;
 
-	MarkAsPreparingGuts(gxact, xid, gid, prepared_at, owner, databaseid);
+	MarkAsPreparingGuts(gxact, fxid, gid, prepared_at, owner, databaseid);
 
 	gxact->ondisk = false;
 
@@ -430,11 +431,13 @@ MarkAsPreparing(TransactionId xid, const char *gid,
  * Note: This function should be called with appropriate locks held.
  */
 static void
-MarkAsPreparingGuts(GlobalTransaction gxact, TransactionId xid, const char *gid,
-					TimestampTz prepared_at, Oid owner, Oid databaseid)
+MarkAsPreparingGuts(GlobalTransaction gxact, FullTransactionId fxid,
+					const char *gid, TimestampTz prepared_at, Oid owner,
+					Oid databaseid)
 {
 	PGPROC	   *proc;
 	int			i;
+	TransactionId xid = XidFromFullTransactionId(fxid);
 
 	Assert(LWLockHeldByMeInMode(TwoPhaseStateLock, LW_EXCLUSIVE));
 
@@ -479,7 +482,7 @@ MarkAsPreparingGuts(GlobalTransaction gxact, TransactionId xid, const char *gid,
 	proc->subxidStatus.count = 0;
 
 	gxact->prepared_at = prepared_at;
-	gxact->xid = xid;
+	gxact->fxid = fxid;
 	gxact->owner = owner;
 	gxact->locking_backend = MyProcNumber;
 	gxact->valid = false;
@@ -797,12 +800,12 @@ pg_prepared_xact(PG_FUNCTION_ARGS)
  * caller had better hold it.
  */
 static GlobalTransaction
-TwoPhaseGetGXact(TransactionId xid, bool lock_held)
+TwoPhaseGetGXact(FullTransactionId fxid, bool lock_held)
 {
 	GlobalTransaction result = NULL;
 	int			i;
 
-	static TransactionId cached_xid = InvalidTransactionId;
+	static FullTransactionId cached_fxid = {InvalidTransactionId};
 	static GlobalTransaction cached_gxact = NULL;
 
 	Assert(!lock_held || LWLockHeldByMe(TwoPhaseStateLock));
@@ -811,7 +814,7 @@ TwoPhaseGetGXact(TransactionId xid, bool lock_held)
 	 * During a recovery, COMMIT PREPARED, or ABORT PREPARED, we'll be called
 	 * repeatedly for the same XID.  We can save work with a simple cache.
 	 */
-	if (xid == cached_xid)
+	if (FullTransactionIdEquals(fxid, cached_fxid))
 		return cached_gxact;
 
 	if (!lock_held)
@@ -821,7 +824,7 @@ TwoPhaseGetGXact(TransactionId xid, bool lock_held)
 	{
 		GlobalTransaction gxact = TwoPhaseState->prepXacts[i];
 
-		if (gxact->xid == xid)
+		if (FullTransactionIdEquals(gxact->fxid, fxid))
 		{
 			result = gxact;
 			break;
@@ -832,9 +835,10 @@ TwoPhaseGetGXact(TransactionId xid, bool lock_held)
 		LWLockRelease(TwoPhaseStateLock);
 
 	if (result == NULL)			/* should not happen */
-		elog(ERROR, "failed to find GlobalTransaction for xid %u", xid);
+		elog(ERROR, "failed to find GlobalTransaction for xid %u",
+			 XidFromFullTransactionId(fxid));
 
-	cached_xid = xid;
+	cached_fxid = fxid;
 	cached_gxact = result;
 
 	return result;
@@ -881,7 +885,7 @@ TwoPhaseGetXidByVirtualXID(VirtualTransactionId vxid,
 				*have_more = true;
 				break;
 			}
-			result = gxact->xid;
+			result = XidFromFullTransactionId(gxact->fxid);
 		}
 	}
 
@@ -892,7 +896,7 @@ TwoPhaseGetXidByVirtualXID(VirtualTransactionId vxid,
 
 /*
  * TwoPhaseGetDummyProcNumber
- *		Get the dummy proc number for prepared transaction specified by XID
+ *		Get the dummy proc number for prepared transaction
  *
  * Dummy proc numbers are similar to proc numbers of real backends.  They
  * start at MaxBackends, and are unique across all currently active real
@@ -900,24 +904,24 @@ TwoPhaseGetXidByVirtualXID(VirtualTransactionId vxid,
  * TwoPhaseStateLock will not be taken, so the caller had better hold it.
  */
 ProcNumber
-TwoPhaseGetDummyProcNumber(TransactionId xid, bool lock_held)
+TwoPhaseGetDummyProcNumber(FullTransactionId fxid, bool lock_held)
 {
-	GlobalTransaction gxact = TwoPhaseGetGXact(xid, lock_held);
+	GlobalTransaction gxact = TwoPhaseGetGXact(fxid, lock_held);
 
 	return gxact->pgprocno;
 }
 
 /*
  * TwoPhaseGetDummyProc
- *		Get the PGPROC that represents a prepared transaction specified by XID
+ *		Get the PGPROC that represents a prepared transaction
  *
  * If lock_held is set to true, TwoPhaseStateLock will not be taken, so the
  * caller had better hold it.
  */
 PGPROC *
-TwoPhaseGetDummyProc(TransactionId xid, bool lock_held)
+TwoPhaseGetDummyProc(FullTransactionId fxid, bool lock_held)
 {
-	GlobalTransaction gxact = TwoPhaseGetGXact(xid, lock_held);
+	GlobalTransaction gxact = TwoPhaseGetGXact(fxid, lock_held);
 
 	return GetPGProcByNumber(gxact->pgprocno);
 }
@@ -942,10 +946,8 @@ AdjustToFullTransactionId(TransactionId xid)
 }
 
 static inline int
-TwoPhaseFilePath(char *path, TransactionId xid)
+TwoPhaseFilePath(char *path, FullTransactionId fxid)
 {
-	FullTransactionId fxid = AdjustToFullTransactionId(xid);
-
 	return snprintf(path, MAXPGPATH, TWOPHASE_DIR "/%08X%08X",
 					EpochFromFullTransactionId(fxid),
 					XidFromFullTransactionId(fxid));
@@ -1049,7 +1051,7 @@ void
 StartPrepare(GlobalTransaction gxact)
 {
 	PGPROC	   *proc = GetPGProcByNumber(gxact->pgprocno);
-	TransactionId xid = gxact->xid;
+	TransactionId xid = XidFromFullTransactionId(gxact->fxid);
 	TwoPhaseFileHeader hdr;
 	TransactionId *children;
 	RelFileLocator *commitrels;
@@ -1181,7 +1183,11 @@ EndPrepare(GlobalTransaction gxact)
 	 * starting immediately after the WAL record is inserted could complete
 	 * without fsync'ing our state file.  (This is essentially the same kind
 	 * of race condition as the COMMIT-to-clog-write case that
-	 * RecordTransactionCommit uses DELAY_CHKPT_START for; see notes there.)
+	 * RecordTransactionCommit uses DELAY_CHKPT_IN_COMMIT for; see notes
+	 * there.) Note that DELAY_CHKPT_IN_COMMIT is used to find transactions in
+	 * the critical commit section. We need to know about such transactions
+	 * for conflict detection in logical replication. See
+	 * GetOldestActiveTransactionId(true, false) and its use.
 	 *
 	 * We save the PREPARE record's location in the gxact for later use by
 	 * CheckPointTwoPhase.
@@ -1281,10 +1287,11 @@ RegisterTwoPhaseRecord(TwoPhaseRmgrId rmid, uint16 info,
  * If it looks OK (has a valid magic number and CRC), return the palloc'd
  * contents of the file, issuing an error when finding corrupted data.  If
  * missing_ok is true, which indicates that missing files can be safely
- * ignored, then return NULL.  This state can be reached when doing recovery.
+ * ignored, then return NULL.  This state can be reached when doing recovery
+ * after discarding two-phase files from frozen epochs.
  */
 static char *
-ReadTwoPhaseFile(TransactionId xid, bool missing_ok)
+ReadTwoPhaseFile(FullTransactionId fxid, bool missing_ok)
 {
 	char		path[MAXPGPATH];
 	char	   *buf;
@@ -1296,7 +1303,7 @@ ReadTwoPhaseFile(TransactionId xid, bool missing_ok)
 				file_crc;
 	int			r;
 
-	TwoPhaseFilePath(path, xid);
+	TwoPhaseFilePath(path, fxid);
 
 	fd = OpenTransientFile(path, O_RDONLY | PG_BINARY);
 	if (fd < 0)
@@ -1426,12 +1433,12 @@ XlogReadTwoPhaseData(XLogRecPtr lsn, char **buf, int *len)
 		if (errormsg)
 			ereport(ERROR,
 					(errcode_for_file_access(),
-					 errmsg("could not read two-phase state from WAL at %X/%X: %s",
+					 errmsg("could not read two-phase state from WAL at %X/%08X: %s",
 							LSN_FORMAT_ARGS(lsn), errormsg)));
 		else
 			ereport(ERROR,
 					(errcode_for_file_access(),
-					 errmsg("could not read two-phase state from WAL at %X/%X",
+					 errmsg("could not read two-phase state from WAL at %X/%08X",
 							LSN_FORMAT_ARGS(lsn))));
 	}
 
@@ -1439,7 +1446,7 @@ XlogReadTwoPhaseData(XLogRecPtr lsn, char **buf, int *len)
 		(XLogRecGetInfo(xlogreader) & XLOG_XACT_OPMASK) != XLOG_XACT_PREPARE)
 		ereport(ERROR,
 				(errcode_for_file_access(),
-				 errmsg("expected two-phase state data is not present in WAL at %X/%X",
+				 errmsg("expected two-phase state data is not present in WAL at %X/%08X",
 						LSN_FORMAT_ARGS(lsn))));
 
 	if (len != NULL)
@@ -1461,6 +1468,7 @@ StandbyTransactionIdIsPrepared(TransactionId xid)
 	char	   *buf;
 	TwoPhaseFileHeader *hdr;
 	bool		result;
+	FullTransactionId fxid;
 
 	Assert(TransactionIdIsValid(xid));
 
@@ -1468,7 +1476,8 @@ StandbyTransactionIdIsPrepared(TransactionId xid)
 		return false;			/* nothing to do */
 
 	/* Read and validate file */
-	buf = ReadTwoPhaseFile(xid, true);
+	fxid = AdjustToFullTransactionId(xid);
+	buf = ReadTwoPhaseFile(fxid, true);
 	if (buf == NULL)
 		return false;
 
@@ -1488,6 +1497,7 @@ FinishPreparedTransaction(const char *gid, bool isCommit)
 {
 	GlobalTransaction gxact;
 	PGPROC	   *proc;
+	FullTransactionId fxid;
 	TransactionId xid;
 	bool		ondisk;
 	char	   *buf;
@@ -1509,7 +1519,8 @@ FinishPreparedTransaction(const char *gid, bool isCommit)
 	 */
 	gxact = LockGXact(gid, GetUserId());
 	proc = GetPGProcByNumber(gxact->pgprocno);
-	xid = gxact->xid;
+	fxid = gxact->fxid;
+	xid = XidFromFullTransactionId(fxid);
 
 	/*
 	 * Read and validate 2PC state data. State data will typically be stored
@@ -1517,7 +1528,7 @@ FinishPreparedTransaction(const char *gid, bool isCommit)
 	 * to disk if for some reason they have lived for a long time.
 	 */
 	if (gxact->ondisk)
-		buf = ReadTwoPhaseFile(xid, false);
+		buf = ReadTwoPhaseFile(fxid, false);
 	else
 		XlogReadTwoPhaseData(gxact->prepare_start_lsn, &buf, NULL);
 
@@ -1636,11 +1647,11 @@ FinishPreparedTransaction(const char *gid, bool isCommit)
 
 	/* And now do the callbacks */
 	if (isCommit)
-		ProcessRecords(bufptr, xid, twophase_postcommit_callbacks);
+		ProcessRecords(bufptr, fxid, twophase_postcommit_callbacks);
 	else
-		ProcessRecords(bufptr, xid, twophase_postabort_callbacks);
+		ProcessRecords(bufptr, fxid, twophase_postabort_callbacks);
 
-	PredicateLockTwoPhaseFinish(xid, isCommit);
+	PredicateLockTwoPhaseFinish(fxid, isCommit);
 
 	/*
 	 * Read this value while holding the two-phase lock, as the on-disk 2PC
@@ -1664,7 +1675,7 @@ FinishPreparedTransaction(const char *gid, bool isCommit)
 	 * And now we can clean up any files we may have left.
 	 */
 	if (ondisk)
-		RemoveTwoPhaseFile(xid, true);
+		RemoveTwoPhaseFile(fxid, true);
 
 	MyLockedGxact = NULL;
 
@@ -1677,7 +1688,7 @@ FinishPreparedTransaction(const char *gid, bool isCommit)
  * Scan 2PC state data in memory and call the indicated callbacks for each 2PC record.
  */
 static void
-ProcessRecords(char *bufptr, TransactionId xid,
+ProcessRecords(char *bufptr, FullTransactionId fxid,
 			   const TwoPhaseCallback callbacks[])
 {
 	for (;;)
@@ -1691,24 +1702,28 @@ ProcessRecords(char *bufptr, TransactionId xid,
 		bufptr += MAXALIGN(sizeof(TwoPhaseRecordOnDisk));
 
 		if (callbacks[record->rmid] != NULL)
-			callbacks[record->rmid] (xid, record->info, bufptr, record->len);
+			callbacks[record->rmid] (fxid, record->info, bufptr, record->len);
 
 		bufptr += MAXALIGN(record->len);
 	}
 }
 
 /*
- * Remove the 2PC file for the specified XID.
+ * Remove the 2PC file.
  *
  * If giveWarning is false, do not complain about file-not-present;
  * this is an expected case during WAL replay.
+ *
+ * This routine is used at early stages at recovery where future and
+ * past orphaned files are checked, hence the FullTransactionId to build
+ * a complete file name fit for the removal.
  */
 static void
-RemoveTwoPhaseFile(TransactionId xid, bool giveWarning)
+RemoveTwoPhaseFile(FullTransactionId fxid, bool giveWarning)
 {
 	char		path[MAXPGPATH];
 
-	TwoPhaseFilePath(path, xid);
+	TwoPhaseFilePath(path, fxid);
 	if (unlink(path))
 		if (errno != ENOENT || giveWarning)
 			ereport(WARNING,
@@ -1723,7 +1738,7 @@ RemoveTwoPhaseFile(TransactionId xid, bool giveWarning)
  * Note: content and len don't include CRC.
  */
 static void
-RecreateTwoPhaseFile(TransactionId xid, void *content, int len)
+RecreateTwoPhaseFile(FullTransactionId fxid, void *content, int len)
 {
 	char		path[MAXPGPATH];
 	pg_crc32c	statefile_crc;
@@ -1734,7 +1749,7 @@ RecreateTwoPhaseFile(TransactionId xid, void *content, int len)
 	COMP_CRC32C(statefile_crc, content, len);
 	FIN_CRC32C(statefile_crc);
 
-	TwoPhaseFilePath(path, xid);
+	TwoPhaseFilePath(path, fxid);
 
 	fd = OpenTransientFile(path,
 						   O_CREAT | O_TRUNC | O_WRONLY | PG_BINARY);
@@ -1846,7 +1861,7 @@ CheckPointTwoPhase(XLogRecPtr redo_horizon)
 			int			len;
 
 			XlogReadTwoPhaseData(gxact->prepare_start_lsn, &buf, &len);
-			RecreateTwoPhaseFile(gxact->xid, buf, len);
+			RecreateTwoPhaseFile(gxact->fxid, buf, len);
 			gxact->ondisk = true;
 			gxact->prepare_start_lsn = InvalidXLogRecPtr;
 			gxact->prepare_end_lsn = InvalidXLogRecPtr;
@@ -1897,19 +1912,17 @@ restoreTwoPhaseData(void)
 		if (strlen(clde->d_name) == 16 &&
 			strspn(clde->d_name, "0123456789ABCDEF") == 16)
 		{
-			TransactionId xid;
 			FullTransactionId fxid;
 			char	   *buf;
 
 			fxid = FullTransactionIdFromU64(strtou64(clde->d_name, NULL, 16));
-			xid = XidFromFullTransactionId(fxid);
 
-			buf = ProcessTwoPhaseBuffer(xid, InvalidXLogRecPtr,
+			buf = ProcessTwoPhaseBuffer(fxid, InvalidXLogRecPtr,
 										true, false, false);
 			if (buf == NULL)
 				continue;
 
-			PrepareRedoAdd(buf, InvalidXLogRecPtr,
+			PrepareRedoAdd(fxid, buf, InvalidXLogRecPtr,
 						   InvalidXLogRecPtr, InvalidRepOriginId);
 		}
 	}
@@ -1968,9 +1981,7 @@ PrescanPreparedTransactions(TransactionId **xids_p, int *nxids_p)
 
 		Assert(gxact->inredo);
 
-		xid = gxact->xid;
-
-		buf = ProcessTwoPhaseBuffer(xid,
+		buf = ProcessTwoPhaseBuffer(gxact->fxid,
 									gxact->prepare_start_lsn,
 									gxact->ondisk, false, true);
 
@@ -1981,6 +1992,7 @@ PrescanPreparedTransactions(TransactionId **xids_p, int *nxids_p)
 		 * OK, we think this file is valid.  Incorporate xid into the
 		 * running-minimum result.
 		 */
+		xid = XidFromFullTransactionId(gxact->fxid);
 		if (TransactionIdPrecedes(xid, result))
 			result = xid;
 
@@ -2036,15 +2048,12 @@ StandbyRecoverPreparedTransactions(void)
 	LWLockAcquire(TwoPhaseStateLock, LW_EXCLUSIVE);
 	for (i = 0; i < TwoPhaseState->numPrepXacts; i++)
 	{
-		TransactionId xid;
 		char	   *buf;
 		GlobalTransaction gxact = TwoPhaseState->prepXacts[i];
 
 		Assert(gxact->inredo);
 
-		xid = gxact->xid;
-
-		buf = ProcessTwoPhaseBuffer(xid,
+		buf = ProcessTwoPhaseBuffer(gxact->fxid,
 									gxact->prepare_start_lsn,
 									gxact->ondisk, true, false);
 		if (buf != NULL)
@@ -2077,16 +2086,14 @@ RecoverPreparedTransactions(void)
 	LWLockAcquire(TwoPhaseStateLock, LW_EXCLUSIVE);
 	for (i = 0; i < TwoPhaseState->numPrepXacts; i++)
 	{
-		TransactionId xid;
 		char	   *buf;
 		GlobalTransaction gxact = TwoPhaseState->prepXacts[i];
+		FullTransactionId fxid = gxact->fxid;
 		char	   *bufptr;
 		TwoPhaseFileHeader *hdr;
 		TransactionId *subxids;
 		const char *gid;
 
-		xid = gxact->xid;
-
 		/*
 		 * Reconstruct subtrans state for the transaction --- needed because
 		 * pg_subtrans is not preserved over a restart.  Note that we are
@@ -2096,17 +2103,20 @@ RecoverPreparedTransactions(void)
 		 * SubTransSetParent has been set before, if the prepared transaction
 		 * generated xid assignment records.
 		 */
-		buf = ProcessTwoPhaseBuffer(xid,
+		buf = ProcessTwoPhaseBuffer(gxact->fxid,
 									gxact->prepare_start_lsn,
 									gxact->ondisk, true, false);
 		if (buf == NULL)
 			continue;
 
 		ereport(LOG,
-				(errmsg("recovering prepared transaction %u from shared memory", xid)));
+				(errmsg("recovering prepared transaction %u of epoch %u from shared memory",
+						XidFromFullTransactionId(gxact->fxid),
+						EpochFromFullTransactionId(gxact->fxid))));
 
 		hdr = (TwoPhaseFileHeader *) buf;
-		Assert(TransactionIdEquals(hdr->xid, xid));
+		Assert(TransactionIdEquals(hdr->xid,
+								   XidFromFullTransactionId(gxact->fxid)));
 		bufptr = buf + MAXALIGN(sizeof(TwoPhaseFileHeader));
 		gid = (const char *) bufptr;
 		bufptr += MAXALIGN(hdr->gidlen);
@@ -2122,7 +2132,7 @@ RecoverPreparedTransactions(void)
 		 * Recreate its GXACT and dummy PGPROC. But, check whether it was
 		 * added in redo and already has a shmem entry for it.
 		 */
-		MarkAsPreparingGuts(gxact, xid, gid,
+		MarkAsPreparingGuts(gxact, gxact->fxid, gid,
 							hdr->prepared_at,
 							hdr->owner, hdr->database);
 
@@ -2137,7 +2147,7 @@ RecoverPreparedTransactions(void)
 		/*
 		 * Recover other state (notably locks) using resource managers.
 		 */
-		ProcessRecords(bufptr, xid, twophase_recover_callbacks);
+		ProcessRecords(bufptr, fxid, twophase_recover_callbacks);
 
 		/*
 		 * Release locks held by the standby process after we process each
@@ -2145,7 +2155,7 @@ RecoverPreparedTransactions(void)
 		 * additional locks at any one time.
 		 */
 		if (InHotStandby)
-			StandbyReleaseLockTree(xid, hdr->nsubxacts, subxids);
+			StandbyReleaseLockTree(hdr->xid, hdr->nsubxacts, subxids);
 
 		/*
 		 * We're done with recovering this transaction. Clear MyLockedGxact,
@@ -2164,7 +2174,7 @@ RecoverPreparedTransactions(void)
 /*
  * ProcessTwoPhaseBuffer
  *
- * Given a transaction id, read it either from disk or read it directly
+ * Given a FullTransactionId, read it either from disk or read it directly
  * via shmem xlog record pointer using the provided "prepare_start_lsn".
  *
  * If setParent is true, set up subtransaction parent linkages.
@@ -2173,13 +2183,12 @@ RecoverPreparedTransactions(void)
  * value scanned.
  */
 static char *
-ProcessTwoPhaseBuffer(TransactionId xid,
+ProcessTwoPhaseBuffer(FullTransactionId fxid,
 					  XLogRecPtr prepare_start_lsn,
 					  bool fromdisk,
 					  bool setParent, bool setNextXid)
 {
 	FullTransactionId nextXid = TransamVariables->nextXid;
-	TransactionId origNextXid = XidFromFullTransactionId(nextXid);
 	TransactionId *subxids;
 	char	   *buf;
 	TwoPhaseFileHeader *hdr;
@@ -2191,41 +2200,46 @@ ProcessTwoPhaseBuffer(TransactionId xid,
 		Assert(prepare_start_lsn != InvalidXLogRecPtr);
 
 	/* Already processed? */
-	if (TransactionIdDidCommit(xid) || TransactionIdDidAbort(xid))
+	if (TransactionIdDidCommit(XidFromFullTransactionId(fxid)) ||
+		TransactionIdDidAbort(XidFromFullTransactionId(fxid)))
 	{
 		if (fromdisk)
 		{
 			ereport(WARNING,
-					(errmsg("removing stale two-phase state file for transaction %u",
-							xid)));
-			RemoveTwoPhaseFile(xid, true);
+					(errmsg("removing stale two-phase state file for transaction %u of epoch %u",
+							XidFromFullTransactionId(fxid),
+							EpochFromFullTransactionId(fxid))));
+			RemoveTwoPhaseFile(fxid, true);
 		}
 		else
 		{
 			ereport(WARNING,
-					(errmsg("removing stale two-phase state from memory for transaction %u",
-							xid)));
-			PrepareRedoRemove(xid, true);
+					(errmsg("removing stale two-phase state from memory for transaction %u of epoch %u",
+							XidFromFullTransactionId(fxid),
+							EpochFromFullTransactionId(fxid))));
+			PrepareRedoRemoveFull(fxid, true);
 		}
 		return NULL;
 	}
 
 	/* Reject XID if too new */
-	if (TransactionIdFollowsOrEquals(xid, origNextXid))
+	if (FullTransactionIdFollowsOrEquals(fxid, nextXid))
 	{
 		if (fromdisk)
 		{
 			ereport(WARNING,
-					(errmsg("removing future two-phase state file for transaction %u",
-							xid)));
-			RemoveTwoPhaseFile(xid, true);
+					(errmsg("removing future two-phase state file for transaction %u of epoch %u",
+							XidFromFullTransactionId(fxid),
+							EpochFromFullTransactionId(fxid))));
+			RemoveTwoPhaseFile(fxid, true);
 		}
 		else
 		{
 			ereport(WARNING,
-					(errmsg("removing future two-phase state from memory for transaction %u",
-							xid)));
-			PrepareRedoRemove(xid, true);
+					(errmsg("removing future two-phase state from memory for transaction %u of epoch %u",
+							XidFromFullTransactionId(fxid),
+							EpochFromFullTransactionId(fxid))));
+			PrepareRedoRemoveFull(fxid, true);
 		}
 		return NULL;
 	}
@@ -2233,7 +2247,7 @@ ProcessTwoPhaseBuffer(TransactionId xid,
 	if (fromdisk)
 	{
 		/* Read and validate file */
-		buf = ReadTwoPhaseFile(xid, false);
+		buf = ReadTwoPhaseFile(fxid, false);
 	}
 	else
 	{
@@ -2243,18 +2257,20 @@ ProcessTwoPhaseBuffer(TransactionId xid,
 
 	/* Deconstruct header */
 	hdr = (TwoPhaseFileHeader *) buf;
-	if (!TransactionIdEquals(hdr->xid, xid))
+	if (!TransactionIdEquals(hdr->xid, XidFromFullTransactionId(fxid)))
 	{
 		if (fromdisk)
 			ereport(ERROR,
 					(errcode(ERRCODE_DATA_CORRUPTED),
-					 errmsg("corrupted two-phase state file for transaction %u",
-							xid)));
+					 errmsg("corrupted two-phase state file for transaction %u of epoch %u",
+							XidFromFullTransactionId(fxid),
+							EpochFromFullTransactionId(fxid))));
 		else
 			ereport(ERROR,
 					(errcode(ERRCODE_DATA_CORRUPTED),
-					 errmsg("corrupted two-phase state in memory for transaction %u",
-							xid)));
+					 errmsg("corrupted two-phase state in memory for transaction %u of epoch %u",
+							XidFromFullTransactionId(fxid),
+							EpochFromFullTransactionId(fxid))));
 	}
 
 	/*
@@ -2268,14 +2284,14 @@ ProcessTwoPhaseBuffer(TransactionId xid,
 	{
 		TransactionId subxid = subxids[i];
 
-		Assert(TransactionIdFollows(subxid, xid));
+		Assert(TransactionIdFollows(subxid, XidFromFullTransactionId(fxid)));
 
 		/* update nextXid if needed */
 		if (setNextXid)
 			AdvanceNextFullTransactionIdPastXid(subxid);
 
 		if (setParent)
-			SubTransSetParent(subxid, xid);
+			SubTransSetParent(subxid, XidFromFullTransactionId(fxid));
 	}
 
 	return buf;
@@ -2286,7 +2302,7 @@ ProcessTwoPhaseBuffer(TransactionId xid,
  *	RecordTransactionCommitPrepared
  *
  * This is basically the same as RecordTransactionCommit (q.v. if you change
- * this function): in particular, we must set DELAY_CHKPT_START to avoid a
+ * this function): in particular, we must set DELAY_CHKPT_IN_COMMIT to avoid a
  * race condition.
  *
  * We know the transaction made at least one XLOG entry (its PREPARE),
@@ -2306,7 +2322,7 @@ RecordTransactionCommitPrepared(TransactionId xid,
 								const char *gid)
 {
 	XLogRecPtr	recptr;
-	TimestampTz committs = GetCurrentTimestamp();
+	TimestampTz committs;
 	bool		replorigin;
 
 	/*
@@ -2319,8 +2335,24 @@ RecordTransactionCommitPrepared(TransactionId xid,
 	START_CRIT_SECTION();
 
 	/* See notes in RecordTransactionCommit */
-	Assert((MyProc->delayChkptFlags & DELAY_CHKPT_START) == 0);
-	MyProc->delayChkptFlags |= DELAY_CHKPT_START;
+	Assert((MyProc->delayChkptFlags & DELAY_CHKPT_IN_COMMIT) == 0);
+	MyProc->delayChkptFlags |= DELAY_CHKPT_IN_COMMIT;
+
+	/*
+	 * Ensures the DELAY_CHKPT_IN_COMMIT flag write is globally visible before
+	 * commit time is written.
+	 */
+	pg_write_barrier();
+
+	/*
+	 * Note it is important to set committs value after marking ourselves as
+	 * in the commit critical section (DELAY_CHKPT_IN_COMMIT). This is because
+	 * we want to ensure all transactions that have acquired commit timestamp
+	 * are finished before we allow the logical replication client to advance
+	 * its xid which is used to hold back dead rows for conflict detection.
+	 * See comments atop worker.c.
+	 */
+	committs = GetCurrentTimestamp();
 
 	/*
 	 * Emit the XLOG commit record. Note that we mark 2PC commits as
@@ -2369,7 +2401,7 @@ RecordTransactionCommitPrepared(TransactionId xid,
 	TransactionIdCommitTree(xid, nchildren, children);
 
 	/* Checkpoint can proceed now */
-	MyProc->delayChkptFlags &= ~DELAY_CHKPT_START;
+	MyProc->delayChkptFlags &= ~DELAY_CHKPT_IN_COMMIT;
 
 	END_CRIT_SECTION();
 
@@ -2466,8 +2498,9 @@ RecordTransactionAbortPrepared(TransactionId xid,
  * data, the entry is marked as located on disk.
  */
 void
-PrepareRedoAdd(char *buf, XLogRecPtr start_lsn,
-			   XLogRecPtr end_lsn, RepOriginId origin_id)
+PrepareRedoAdd(FullTransactionId fxid, char *buf,
+			   XLogRecPtr start_lsn, XLogRecPtr end_lsn,
+			   RepOriginId origin_id)
 {
 	TwoPhaseFileHeader *hdr = (TwoPhaseFileHeader *) buf;
 	char	   *bufptr;
@@ -2477,6 +2510,13 @@ PrepareRedoAdd(char *buf, XLogRecPtr start_lsn,
 	Assert(LWLockHeldByMeInMode(TwoPhaseStateLock, LW_EXCLUSIVE));
 	Assert(RecoveryInProgress());
 
+	if (!FullTransactionIdIsValid(fxid))
+	{
+		Assert(InRecovery);
+		fxid = FullTransactionIdFromAllowableAt(TransamVariables->nextXid,
+												hdr->xid);
+	}
+
 	bufptr = buf + MAXALIGN(sizeof(TwoPhaseFileHeader));
 	gid = (const char *) bufptr;
 
@@ -2505,14 +2545,15 @@ PrepareRedoAdd(char *buf, XLogRecPtr start_lsn,
 	{
 		char		path[MAXPGPATH];
 
-		TwoPhaseFilePath(path, hdr->xid);
+		Assert(InRecovery);
+		TwoPhaseFilePath(path, fxid);
 
 		if (access(path, F_OK) == 0)
 		{
 			ereport(reachedConsistency ? ERROR : WARNING,
 					(errmsg("could not recover two-phase state file for transaction %u",
 							hdr->xid),
-					 errdetail("Two-phase state file has been found in WAL record %X/%X, but this transaction has already been restored from disk.",
+					 errdetail("Two-phase state file has been found in WAL record %X/%08X, but this transaction has already been restored from disk.",
 							   LSN_FORMAT_ARGS(start_lsn))));
 			return;
 		}
@@ -2536,7 +2577,7 @@ PrepareRedoAdd(char *buf, XLogRecPtr start_lsn,
 	gxact->prepared_at = hdr->prepared_at;
 	gxact->prepare_start_lsn = start_lsn;
 	gxact->prepare_end_lsn = end_lsn;
-	gxact->xid = hdr->xid;
+	gxact->fxid = fxid;
 	gxact->owner = hdr->owner;
 	gxact->locking_backend = INVALID_PROC_NUMBER;
 	gxact->valid = false;
@@ -2555,11 +2596,13 @@ PrepareRedoAdd(char *buf, XLogRecPtr start_lsn,
 						   false /* backward */ , false /* WAL */ );
 	}
 
-	elog(DEBUG2, "added 2PC data in shared memory for transaction %u", gxact->xid);
+	elog(DEBUG2, "added 2PC data in shared memory for transaction %u of epoch %u",
+		 XidFromFullTransactionId(gxact->fxid),
+		 EpochFromFullTransactionId(gxact->fxid));
 }
 
 /*
- * PrepareRedoRemove
+ * PrepareRedoRemoveFull
  *
  * Remove the corresponding gxact entry from TwoPhaseState. Also remove
  * the 2PC file if a prepared transaction was saved via an earlier checkpoint.
@@ -2567,8 +2610,8 @@ PrepareRedoAdd(char *buf, XLogRecPtr start_lsn,
  * Caller must hold TwoPhaseStateLock in exclusive mode, because TwoPhaseState
  * is updated.
  */
-void
-PrepareRedoRemove(TransactionId xid, bool giveWarning)
+static void
+PrepareRedoRemoveFull(FullTransactionId fxid, bool giveWarning)
 {
 	GlobalTransaction gxact = NULL;
 	int			i;
@@ -2581,7 +2624,7 @@ PrepareRedoRemove(TransactionId xid, bool giveWarning)
 	{
 		gxact = TwoPhaseState->prepXacts[i];
 
-		if (gxact->xid == xid)
+		if (FullTransactionIdEquals(gxact->fxid, fxid))
 		{
 			Assert(gxact->inredo);
 			found = true;
@@ -2598,12 +2641,28 @@ PrepareRedoRemove(TransactionId xid, bool giveWarning)
 	/*
 	 * And now we can clean up any files we may have left.
 	 */
-	elog(DEBUG2, "removing 2PC data for transaction %u", xid);
+	elog(DEBUG2, "removing 2PC data for transaction %u of epoch %u ",
+		 XidFromFullTransactionId(fxid),
+		 EpochFromFullTransactionId(fxid));
+
 	if (gxact->ondisk)
-		RemoveTwoPhaseFile(xid, giveWarning);
+		RemoveTwoPhaseFile(fxid, giveWarning);
+
 	RemoveGXact(gxact);
 }
 
+/*
+ * Wrapper of PrepareRedoRemoveFull(), for TransactionIds.
+ */
+void
+PrepareRedoRemove(TransactionId xid, bool giveWarning)
+{
+	FullTransactionId fxid =
+		FullTransactionIdFromAllowableAt(TransamVariables->nextXid, xid);
+
+	PrepareRedoRemoveFull(fxid, giveWarning);
+}
+
 /*
  * LookupGXact
  *		Check if the prepared transaction with the given GID, lsn and timestamp
@@ -2648,7 +2707,7 @@ LookupGXact(const char *gid, XLogRecPtr prepare_end_lsn,
 			 * between publisher and subscriber.
 			 */
 			if (gxact->ondisk)
-				buf = ReadTwoPhaseFile(gxact->xid, false);
+				buf = ReadTwoPhaseFile(gxact->fxid, false);
 			else
 			{
 				Assert(gxact->prepare_start_lsn);
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index b885513f76541..b46e7e9c2a6b0 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -1431,10 +1431,22 @@ RecordTransactionCommit(void)
 		 * without holding the ProcArrayLock, since we're the only one
 		 * modifying it.  This makes checkpoint's determination of which xacts
 		 * are delaying the checkpoint a bit fuzzy, but it doesn't matter.
+		 *
+		 * Note, it is important to get the commit timestamp after marking the
+		 * transaction in the commit critical section. See
+		 * RecordTransactionCommitPrepared.
 		 */
-		Assert((MyProc->delayChkptFlags & DELAY_CHKPT_START) == 0);
+		Assert((MyProc->delayChkptFlags & DELAY_CHKPT_IN_COMMIT) == 0);
 		START_CRIT_SECTION();
-		MyProc->delayChkptFlags |= DELAY_CHKPT_START;
+		MyProc->delayChkptFlags |= DELAY_CHKPT_IN_COMMIT;
+
+		Assert(xactStopTimestamp == 0);
+
+		/*
+		 * Ensures the DELAY_CHKPT_IN_COMMIT flag write is globally visible
+		 * before commit time is written.
+		 */
+		pg_write_barrier();
 
 		/*
 		 * Insert the commit XLOG record.
@@ -1537,7 +1549,7 @@ RecordTransactionCommit(void)
 	 */
 	if (markXidCommitted)
 	{
-		MyProc->delayChkptFlags &= ~DELAY_CHKPT_START;
+		MyProc->delayChkptFlags &= ~DELAY_CHKPT_IN_COMMIT;
 		END_CRIT_SECTION();
 	}
 
@@ -2515,7 +2527,7 @@ static void
 PrepareTransaction(void)
 {
 	TransactionState s = CurrentTransactionState;
-	TransactionId xid = GetCurrentTransactionId();
+	FullTransactionId fxid = GetCurrentFullTransactionId();
 	GlobalTransaction gxact;
 	TimestampTz prepared_at;
 
@@ -2644,7 +2656,7 @@ PrepareTransaction(void)
 	 * Reserve the GID for this transaction. This could fail if the requested
 	 * GID is invalid or already in use.
 	 */
-	gxact = MarkAsPreparing(xid, prepareGID, prepared_at,
+	gxact = MarkAsPreparing(fxid, prepareGID, prepared_at,
 							GetUserId(), MyDatabaseId);
 	prepareGID = NULL;
 
@@ -2694,7 +2706,7 @@ PrepareTransaction(void)
 	 * ProcArrayClearTransaction().  Otherwise, a GetLockConflicts() would
 	 * conclude "xact already committed or aborted" for our locks.
 	 */
-	PostPrepare_Locks(xid);
+	PostPrepare_Locks(fxid);
 
 	/*
 	 * Let others know about no transaction in progress by me.  This has to be
@@ -2738,9 +2750,9 @@ PrepareTransaction(void)
 
 	PostPrepare_smgr();
 
-	PostPrepare_MultiXact(xid);
+	PostPrepare_MultiXact(fxid);
 
-	PostPrepare_PredicateLocks(xid);
+	PostPrepare_PredicateLocks(fxid);
 
 	ResourceOwnerRelease(TopTransactionResourceOwner,
 						 RESOURCE_RELEASE_LOCKS,
@@ -6420,7 +6432,8 @@ xact_redo(XLogReaderState *record)
 		 * gxact entry.
 		 */
 		LWLockAcquire(TwoPhaseStateLock, LW_EXCLUSIVE);
-		PrepareRedoAdd(XLogRecGetData(record),
+		PrepareRedoAdd(InvalidFullTransactionId,
+					   XLogRecGetData(record),
 					   record->ReadRecPtr,
 					   record->EndRecPtr,
 					   XLogRecGetOrigin(record));
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 47ffc0a230772..9a4de1616bcc9 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -96,6 +96,7 @@
 #include "utils/guc_hooks.h"
 #include "utils/guc_tables.h"
 #include "utils/injection_point.h"
+#include "utils/pgstat_internal.h"
 #include "utils/ps_status.h"
 #include "utils/relmapper.h"
 #include "utils/snapmgr.h"
@@ -449,7 +450,6 @@ typedef struct XLogCtlData
 	/* Protected by info_lck: */
 	XLogwrtRqst LogwrtRqst;
 	XLogRecPtr	RedoRecPtr;		/* a recent copy of Insert->RedoRecPtr */
-	FullTransactionId ckptFullXid;	/* nextXid of latest checkpoint */
 	XLogRecPtr	asyncXactLSN;	/* LSN of newest async commit/abort */
 	XLogRecPtr	replicationSlotMinLSN;	/* oldest LSN needed by any slot */
 
@@ -703,7 +703,7 @@ static void InitControlFile(uint64 sysidentifier, uint32 data_checksum_version);
 static void WriteControlFile(void);
 static void ReadControlFile(void);
 static void UpdateControlFile(void);
-static char *str_time(pg_time_t tnow);
+static char *str_time(pg_time_t tnow, char *buf, size_t bufsize);
 
 static int	get_sync_bit(int method);
 
@@ -1028,7 +1028,7 @@ XLogInsertRecord(XLogRecData *rdata,
 		oldCxt = MemoryContextSwitchTo(walDebugCxt);
 
 		initStringInfo(&buf);
-		appendStringInfo(&buf, "INSERT @ %X/%X: ", LSN_FORMAT_ARGS(EndPos));
+		appendStringInfo(&buf, "INSERT @ %X/%08X: ", LSN_FORMAT_ARGS(EndPos));
 
 		/*
 		 * We have to piece together the WAL record data from the XLogRecData
@@ -1092,6 +1092,9 @@ XLogInsertRecord(XLogRecData *rdata,
 		pgWalUsage.wal_bytes += rechdr->xl_tot_len;
 		pgWalUsage.wal_records++;
 		pgWalUsage.wal_fpi += num_fpi;
+
+		/* Required for the flush of pending stats WAL data */
+		pgstat_report_fixed = true;
 	}
 
 	return EndPos;
@@ -1549,8 +1552,8 @@ WaitXLogInsertionsToFinish(XLogRecPtr upto)
 	if (upto > reservedUpto)
 	{
 		ereport(LOG,
-				(errmsg("request to flush past end of generated WAL; request %X/%X, current position %X/%X",
-						LSN_FORMAT_ARGS(upto), LSN_FORMAT_ARGS(reservedUpto))));
+				errmsg("request to flush past end of generated WAL; request %X/%08X, current position %X/%08X",
+					   LSN_FORMAT_ARGS(upto), LSN_FORMAT_ARGS(reservedUpto)));
 		upto = reservedUpto;
 	}
 
@@ -1716,7 +1719,7 @@ GetXLogBuffer(XLogRecPtr ptr, TimeLineID tli)
 		endptr = pg_atomic_read_u64(&XLogCtl->xlblocks[idx]);
 
 		if (expectedEndPtr != endptr)
-			elog(PANIC, "could not find WAL buffer for %X/%X",
+			elog(PANIC, "could not find WAL buffer for %X/%08X",
 				 LSN_FORMAT_ARGS(ptr));
 	}
 	else
@@ -1776,7 +1779,7 @@ WALReadFromBuffers(char *dstbuf, XLogRecPtr startptr, Size count,
 	inserted = pg_atomic_read_u64(&XLogCtl->logInsertResult);
 	if (startptr + count > inserted)
 		ereport(ERROR,
-				errmsg("cannot read past end of generated WAL: requested %X/%X, current position %X/%X",
+				errmsg("cannot read past end of generated WAL: requested %X/%08X, current position %X/%08X",
 					   LSN_FORMAT_ARGS(startptr + count),
 					   LSN_FORMAT_ARGS(inserted)));
 
@@ -2109,6 +2112,12 @@ AdvanceXLInsertBuffer(XLogRecPtr upto, TimeLineID tli, bool opportunistic)
 					LWLockRelease(WALWriteLock);
 					pgWalUsage.wal_buffers_full++;
 					TRACE_POSTGRESQL_WAL_BUFFER_WRITE_DIRTY_DONE();
+
+					/*
+					 * Required for the flush of pending stats WAL data, per
+					 * update of pgWalUsage.
+					 */
+					pgstat_report_fixed = true;
 				}
 			}
 		}
@@ -2281,7 +2290,7 @@ AdvanceXLInsertBuffer(XLogRecPtr upto, TimeLineID tli, bool opportunistic)
 #ifdef WAL_DEBUG
 	if (XLOG_DEBUG && npages > 0)
 	{
-		elog(DEBUG1, "initialized %d pages, up to %X/%X",
+		elog(DEBUG1, "initialized %d pages, up to %X/%08X",
 			 npages, LSN_FORMAT_ARGS(NewPageEndPtr));
 	}
 #endif
@@ -2346,25 +2355,6 @@ check_wal_segment_size(int *newval, void **extra, GucSource source)
 	return true;
 }
 
-/*
- * GUC check_hook for max_slot_wal_keep_size
- *
- * We don't allow the value of max_slot_wal_keep_size other than -1 during the
- * binary upgrade. See start_postmaster() in pg_upgrade for more details.
- */
-bool
-check_max_slot_wal_keep_size(int *newval, void **extra, GucSource source)
-{
-	if (IsBinaryUpgrade && *newval != -1)
-	{
-		GUC_check_errdetail("\"%s\" must be set to -1 during binary upgrade mode.",
-							"max_slot_wal_keep_size");
-		return false;
-	}
-
-	return true;
-}
-
 /*
  * At a checkpoint, how many WAL segments to recycle as preallocated future
  * XLOG segments? Returns the highest segment that should be preallocated.
@@ -2492,7 +2482,7 @@ XLogWrite(XLogwrtRqst WriteRqst, TimeLineID tli, bool flexible)
 		XLogRecPtr	EndPtr = pg_atomic_read_u64(&XLogCtl->xlblocks[curridx]);
 
 		if (LogwrtResult.Write >= EndPtr)
-			elog(PANIC, "xlog write request %X/%X is past end of log %X/%X",
+			elog(PANIC, "xlog write request %X/%08X is past end of log %X/%08X",
 				 LSN_FORMAT_ARGS(LogwrtResult.Write),
 				 LSN_FORMAT_ARGS(EndPtr));
 
@@ -2892,7 +2882,7 @@ UpdateMinRecoveryPoint(XLogRecPtr lsn, bool force)
 		newMinRecoveryPoint = GetCurrentReplayRecPtr(&newMinRecoveryPointTLI);
 		if (!force && newMinRecoveryPoint < lsn)
 			elog(WARNING,
-				 "xlog min recovery request %X/%X is past current point %X/%X",
+				 "xlog min recovery request %X/%08X is past current point %X/%08X",
 				 LSN_FORMAT_ARGS(lsn), LSN_FORMAT_ARGS(newMinRecoveryPoint));
 
 		/* update control file */
@@ -2905,9 +2895,9 @@ UpdateMinRecoveryPoint(XLogRecPtr lsn, bool force)
 			LocalMinRecoveryPointTLI = newMinRecoveryPointTLI;
 
 			ereport(DEBUG2,
-					(errmsg_internal("updated min recovery point to %X/%X on timeline %u",
-									 LSN_FORMAT_ARGS(newMinRecoveryPoint),
-									 newMinRecoveryPointTLI)));
+					errmsg_internal("updated min recovery point to %X/%08X on timeline %u",
+									LSN_FORMAT_ARGS(newMinRecoveryPoint),
+									newMinRecoveryPointTLI));
 		}
 	}
 	LWLockRelease(ControlFileLock);
@@ -2945,7 +2935,7 @@ XLogFlush(XLogRecPtr record)
 
 #ifdef WAL_DEBUG
 	if (XLOG_DEBUG)
-		elog(LOG, "xlog flush request %X/%X; write %X/%X; flush %X/%X",
+		elog(LOG, "xlog flush request %X/%08X; write %X/%08X; flush %X/%08X",
 			 LSN_FORMAT_ARGS(record),
 			 LSN_FORMAT_ARGS(LogwrtResult.Write),
 			 LSN_FORMAT_ARGS(LogwrtResult.Flush));
@@ -3078,7 +3068,7 @@ XLogFlush(XLogRecPtr record)
 	 */
 	if (LogwrtResult.Flush < record)
 		elog(ERROR,
-			 "xlog flush request %X/%X is not satisfied --- flushed only to %X/%X",
+			 "xlog flush request %X/%08X is not satisfied --- flushed only to %X/%08X",
 			 LSN_FORMAT_ARGS(record),
 			 LSN_FORMAT_ARGS(LogwrtResult.Flush));
 }
@@ -3205,7 +3195,7 @@ XLogBackgroundFlush(void)
 
 #ifdef WAL_DEBUG
 	if (XLOG_DEBUG)
-		elog(LOG, "xlog bg flush request write %X/%X; flush: %X/%X, current is write %X/%X; flush %X/%X",
+		elog(LOG, "xlog bg flush request write %X/%08X; flush: %X/%08X, current is write %X/%08X; flush %X/%08X",
 			 LSN_FORMAT_ARGS(WriteRqst.Write),
 			 LSN_FORMAT_ARGS(WriteRqst.Flush),
 			 LSN_FORMAT_ARGS(LogwrtResult.Write),
@@ -5381,11 +5371,9 @@ BootStrapXLOG(uint32 data_checksum_version)
 }
 
 static char *
-str_time(pg_time_t tnow)
+str_time(pg_time_t tnow, char *buf, size_t bufsize)
 {
-	char	   *buf = palloc(128);
-
-	pg_strftime(buf, 128,
+	pg_strftime(buf, bufsize,
 				"%Y-%m-%d %H:%M:%S %Z",
 				pg_localtime(&tnow, log_timezone));
 
@@ -5628,6 +5616,7 @@ StartupXLOG(void)
 	XLogRecPtr	missingContrecPtr;
 	TransactionId oldestActiveXID;
 	bool		promoted = false;
+	char		timebuf[128];
 
 	/*
 	 * We should have an aux process resource owner to use, and we should not
@@ -5656,25 +5645,29 @@ StartupXLOG(void)
 			 */
 			ereport(IsPostmasterEnvironment ? LOG : NOTICE,
 					(errmsg("database system was shut down at %s",
-							str_time(ControlFile->time))));
+							str_time(ControlFile->time,
+									 timebuf, sizeof(timebuf)))));
 			break;
 
 		case DB_SHUTDOWNED_IN_RECOVERY:
 			ereport(LOG,
 					(errmsg("database system was shut down in recovery at %s",
-							str_time(ControlFile->time))));
+							str_time(ControlFile->time,
+									 timebuf, sizeof(timebuf)))));
 			break;
 
 		case DB_SHUTDOWNING:
 			ereport(LOG,
 					(errmsg("database system shutdown was interrupted; last known up at %s",
-							str_time(ControlFile->time))));
+							str_time(ControlFile->time,
+									 timebuf, sizeof(timebuf)))));
 			break;
 
 		case DB_IN_CRASH_RECOVERY:
 			ereport(LOG,
 					(errmsg("database system was interrupted while in recovery at %s",
-							str_time(ControlFile->time)),
+							str_time(ControlFile->time,
+									 timebuf, sizeof(timebuf))),
 					 errhint("This probably means that some data is corrupted and"
 							 " you will have to use the last backup for recovery.")));
 			break;
@@ -5682,7 +5675,8 @@ StartupXLOG(void)
 		case DB_IN_ARCHIVE_RECOVERY:
 			ereport(LOG,
 					(errmsg("database system was interrupted while in recovery at log time %s",
-							str_time(ControlFile->checkPointCopy.time)),
+							str_time(ControlFile->checkPointCopy.time,
+									 timebuf, sizeof(timebuf))),
 					 errhint("If this has occurred more than once some data might be corrupted"
 							 " and you might need to choose an earlier recovery target.")));
 			break;
@@ -5690,7 +5684,8 @@ StartupXLOG(void)
 		case DB_IN_PRODUCTION:
 			ereport(LOG,
 					(errmsg("database system was interrupted; last known up at %s",
-							str_time(ControlFile->time))));
+							str_time(ControlFile->time,
+									 timebuf, sizeof(timebuf)))));
 			break;
 
 		default:
@@ -5763,7 +5758,6 @@ StartupXLOG(void)
 	SetMultiXactIdLimit(checkPoint.oldestMulti, checkPoint.oldestMultiDB, true);
 	SetCommitTsLimit(checkPoint.oldestCommitTsXid,
 					 checkPoint.newestCommitTsXid);
-	XLogCtl->ckptFullXid = checkPoint.nextXid;
 
 	/*
 	 * Clear out any old relcache cache files.  This is *necessary* if we do
@@ -6336,6 +6330,12 @@ StartupXLOG(void)
 	 */
 	CompleteCommitTsInitialization();
 
+	/* Clean up EndOfWalRecoveryInfo data to appease Valgrind leak checking */
+	if (endOfRecoveryInfo->lastPage)
+		pfree(endOfRecoveryInfo->lastPage);
+	pfree(endOfRecoveryInfo->recoveryStopReason);
+	pfree(endOfRecoveryInfo);
+
 	/*
 	 * All done with end-of-recovery actions.
 	 *
@@ -6505,7 +6505,7 @@ PerformRecoveryXLogAction(void)
 	else
 	{
 		RequestCheckpoint(CHECKPOINT_END_OF_RECOVERY |
-						  CHECKPOINT_IMMEDIATE |
+						  CHECKPOINT_FAST |
 						  CHECKPOINT_WAIT);
 	}
 
@@ -6814,7 +6814,7 @@ ShutdownXLOG(int code, Datum arg)
 	WalSndWaitStopping();
 
 	if (RecoveryInProgress())
-		CreateRestartPoint(CHECKPOINT_IS_SHUTDOWN | CHECKPOINT_IMMEDIATE);
+		CreateRestartPoint(CHECKPOINT_IS_SHUTDOWN | CHECKPOINT_FAST);
 	else
 	{
 		/*
@@ -6826,7 +6826,7 @@ ShutdownXLOG(int code, Datum arg)
 		if (XLogArchivingActive())
 			RequestXLogSwitch(false);
 
-		CreateCheckPoint(CHECKPOINT_IS_SHUTDOWN | CHECKPOINT_IMMEDIATE);
+		CreateCheckPoint(CHECKPOINT_IS_SHUTDOWN | CHECKPOINT_FAST);
 	}
 }
 
@@ -6842,24 +6842,24 @@ LogCheckpointStart(int flags, bool restartpoint)
 				(errmsg("restartpoint starting:%s%s%s%s%s%s%s%s",
 						(flags & CHECKPOINT_IS_SHUTDOWN) ? " shutdown" : "",
 						(flags & CHECKPOINT_END_OF_RECOVERY) ? " end-of-recovery" : "",
-						(flags & CHECKPOINT_IMMEDIATE) ? " immediate" : "",
+						(flags & CHECKPOINT_FAST) ? " fast" : "",
 						(flags & CHECKPOINT_FORCE) ? " force" : "",
 						(flags & CHECKPOINT_WAIT) ? " wait" : "",
 						(flags & CHECKPOINT_CAUSE_XLOG) ? " wal" : "",
 						(flags & CHECKPOINT_CAUSE_TIME) ? " time" : "",
-						(flags & CHECKPOINT_FLUSH_ALL) ? " flush-all" : "")));
+						(flags & CHECKPOINT_FLUSH_UNLOGGED) ? " flush-unlogged" : "")));
 	else
 		ereport(LOG,
 		/* translator: the placeholders show checkpoint options */
 				(errmsg("checkpoint starting:%s%s%s%s%s%s%s%s",
 						(flags & CHECKPOINT_IS_SHUTDOWN) ? " shutdown" : "",
 						(flags & CHECKPOINT_END_OF_RECOVERY) ? " end-of-recovery" : "",
-						(flags & CHECKPOINT_IMMEDIATE) ? " immediate" : "",
+						(flags & CHECKPOINT_FAST) ? " fast" : "",
 						(flags & CHECKPOINT_FORCE) ? " force" : "",
 						(flags & CHECKPOINT_WAIT) ? " wait" : "",
 						(flags & CHECKPOINT_CAUSE_XLOG) ? " wal" : "",
 						(flags & CHECKPOINT_CAUSE_TIME) ? " time" : "",
-						(flags & CHECKPOINT_FLUSH_ALL) ? " flush-all" : "")));
+						(flags & CHECKPOINT_FLUSH_UNLOGGED) ? " flush-unlogged" : "")));
 }
 
 /*
@@ -6921,7 +6921,7 @@ LogCheckpointEnd(bool restartpoint)
 						"%d removed, %d recycled; write=%ld.%03d s, "
 						"sync=%ld.%03d s, total=%ld.%03d s; sync files=%d, "
 						"longest=%ld.%03d s, average=%ld.%03d s; distance=%d kB, "
-						"estimate=%d kB; lsn=%X/%X, redo lsn=%X/%X",
+						"estimate=%d kB; lsn=%X/%08X, redo lsn=%X/%08X",
 						CheckpointStats.ckpt_bufs_written,
 						(double) CheckpointStats.ckpt_bufs_written * 100 / NBuffers,
 						CheckpointStats.ckpt_slru_written,
@@ -6945,7 +6945,7 @@ LogCheckpointEnd(bool restartpoint)
 						"%d removed, %d recycled; write=%ld.%03d s, "
 						"sync=%ld.%03d s, total=%ld.%03d s; sync files=%d, "
 						"longest=%ld.%03d s, average=%ld.%03d s; distance=%d kB, "
-						"estimate=%d kB; lsn=%X/%X, redo lsn=%X/%X",
+						"estimate=%d kB; lsn=%X/%08X, redo lsn=%X/%08X",
 						CheckpointStats.ckpt_bufs_written,
 						(double) CheckpointStats.ckpt_bufs_written * 100 / NBuffers,
 						CheckpointStats.ckpt_slru_written,
@@ -7042,12 +7042,12 @@ update_checkpoint_display(int flags, bool restartpoint, bool reset)
  * flags is a bitwise OR of the following:
  *	CHECKPOINT_IS_SHUTDOWN: checkpoint is for database shutdown.
  *	CHECKPOINT_END_OF_RECOVERY: checkpoint is for end of WAL recovery.
- *	CHECKPOINT_IMMEDIATE: finish the checkpoint ASAP,
- *		ignoring checkpoint_completion_target parameter.
+ *	CHECKPOINT_FAST: finish the checkpoint ASAP, ignoring
+ *		checkpoint_completion_target parameter.
  *	CHECKPOINT_FORCE: force a checkpoint even if no XLOG activity has occurred
  *		since the last one (implied by CHECKPOINT_IS_SHUTDOWN or
  *		CHECKPOINT_END_OF_RECOVERY).
- *	CHECKPOINT_FLUSH_ALL: also flush buffers of unlogged tables.
+ *	CHECKPOINT_FLUSH_UNLOGGED: also flush buffers of unlogged tables.
  *
  * Note: flags contains other bits, of interest here only for logging purposes.
  * In particular note that this routine is synchronous and does not pay
@@ -7142,7 +7142,7 @@ CreateCheckPoint(int flags)
 	 * starting snapshot of locks and transactions.
 	 */
 	if (!shutdown && XLogStandbyInfoActive())
-		checkPoint.oldestActiveXid = GetOldestActiveTransactionId();
+		checkPoint.oldestActiveXid = GetOldestActiveTransactionId(false, true);
 	else
 		checkPoint.oldestActiveXid = InvalidTransactionId;
 
@@ -7456,11 +7456,6 @@ CreateCheckPoint(int flags)
 	UpdateControlFile();
 	LWLockRelease(ControlFileLock);
 
-	/* Update shared-memory copy of checkpoint XID/epoch */
-	SpinLockAcquire(&XLogCtl->info_lck);
-	XLogCtl->ckptFullXid = checkPoint.nextXid;
-	SpinLockRelease(&XLogCtl->info_lck);
-
 	/*
 	 * We are now done with critical updates; no need for system panic if we
 	 * have trouble while fooling with old log segments.
@@ -7641,7 +7636,7 @@ CreateOverwriteContrecordRecord(XLogRecPtr aborted_lsn, XLogRecPtr pagePtr,
 	if (!RecoveryInProgress())
 		elog(ERROR, "can only be used at end of recovery");
 	if (pagePtr % XLOG_BLCKSZ != 0)
-		elog(ERROR, "invalid position for missing continuation record %X/%X",
+		elog(ERROR, "invalid position for missing continuation record %X/%08X",
 			 LSN_FORMAT_ARGS(pagePtr));
 
 	/* The current WAL insert position should be right after the page header */
@@ -7652,7 +7647,7 @@ CreateOverwriteContrecordRecord(XLogRecPtr aborted_lsn, XLogRecPtr pagePtr,
 		startPos += SizeOfXLogShortPHD;
 	recptr = GetXLogInsertRecPtr();
 	if (recptr != startPos)
-		elog(ERROR, "invalid WAL insert position %X/%X for OVERWRITE_CONTRECORD",
+		elog(ERROR, "invalid WAL insert position %X/%08X for OVERWRITE_CONTRECORD",
 			 LSN_FORMAT_ARGS(recptr));
 
 	START_CRIT_SECTION();
@@ -7682,7 +7677,7 @@ CreateOverwriteContrecordRecord(XLogRecPtr aborted_lsn, XLogRecPtr pagePtr,
 
 	/* check that the record was inserted to the right place */
 	if (ProcLastRecPtr != startPos)
-		elog(ERROR, "OVERWRITE_CONTRECORD was inserted to unexpected position %X/%X",
+		elog(ERROR, "OVERWRITE_CONTRECORD was inserted to unexpected position %X/%08X",
 			 LSN_FORMAT_ARGS(ProcLastRecPtr));
 
 	XLogFlush(recptr);
@@ -7751,8 +7746,7 @@ RecoveryRestartPoint(const CheckPoint *checkPoint, XLogReaderState *record)
 	if (XLogHaveInvalidPages())
 	{
 		elog(DEBUG2,
-			 "could not record restart point at %X/%X because there "
-			 "are unresolved references to invalid pages",
+			 "could not record restart point at %X/%08X because there are unresolved references to invalid pages",
 			 LSN_FORMAT_ARGS(checkPoint->redo));
 		return;
 	}
@@ -7832,8 +7826,8 @@ CreateRestartPoint(int flags)
 		lastCheckPoint.redo <= ControlFile->checkPointCopy.redo)
 	{
 		ereport(DEBUG2,
-				(errmsg_internal("skipping restartpoint, already performed at %X/%X",
-								 LSN_FORMAT_ARGS(lastCheckPoint.redo))));
+				errmsg_internal("skipping restartpoint, already performed at %X/%08X",
+								LSN_FORMAT_ARGS(lastCheckPoint.redo)));
 
 		UpdateMinRecoveryPoint(InvalidXLogRecPtr, true);
 		if (flags & CHECKPOINT_IS_SHUTDOWN)
@@ -8017,10 +8011,10 @@ CreateRestartPoint(int flags)
 
 	xtime = GetLatestXTime();
 	ereport((log_checkpoints ? LOG : DEBUG2),
-			(errmsg("recovery restart point at %X/%X",
-					LSN_FORMAT_ARGS(lastCheckPoint.redo)),
-			 xtime ? errdetail("Last completed transaction was at log time %s.",
-							   timestamptz_to_str(xtime)) : 0));
+			errmsg("recovery restart point at %X/%08X",
+				   LSN_FORMAT_ARGS(lastCheckPoint.redo)),
+			xtime ? errdetail("Last completed transaction was at log time %s.",
+							  timestamptz_to_str(xtime)) : 0);
 
 	/*
 	 * Finally, execute archive_cleanup_command, if any.
@@ -8151,17 +8145,19 @@ KeepLogSeg(XLogRecPtr recptr, XLogSegNo *logSegNo)
 	XLByteToSeg(recptr, currSegNo, wal_segment_size);
 	segno = currSegNo;
 
-	/*
-	 * Calculate how many segments are kept by slots first, adjusting for
-	 * max_slot_wal_keep_size.
-	 */
+	/* Calculate how many segments are kept by slots. */
 	keep = XLogGetReplicationSlotMinimumLSN();
 	if (keep != InvalidXLogRecPtr && keep < recptr)
 	{
 		XLByteToSeg(keep, segno, wal_segment_size);
 
-		/* Cap by max_slot_wal_keep_size ... */
-		if (max_slot_wal_keep_size_mb >= 0)
+		/*
+		 * Account for max_slot_wal_keep_size to avoid keeping more than
+		 * configured.  However, don't do that during a binary upgrade: if
+		 * slots were to be invalidated because of this, it would not be
+		 * possible to preserve logical ones during the upgrade.
+		 */
+		if (max_slot_wal_keep_size_mb >= 0 && !IsBinaryUpgrade)
 		{
 			uint64		slot_keep_segs;
 
@@ -8281,8 +8277,8 @@ XLogRestorePoint(const char *rpName)
 	RecPtr = XLogInsert(RM_XLOG_ID, XLOG_RESTORE_POINT);
 
 	ereport(LOG,
-			(errmsg("restore point \"%s\" created at %X/%X",
-					rpName, LSN_FORMAT_ARGS(RecPtr))));
+			errmsg("restore point \"%s\" created at %X/%08X",
+				   rpName, LSN_FORMAT_ARGS(RecPtr)));
 
 	return RecPtr;
 }
@@ -8534,11 +8530,6 @@ xlog_redo(XLogReaderState *record)
 		ControlFile->checkPointCopy.nextXid = checkPoint.nextXid;
 		LWLockRelease(ControlFileLock);
 
-		/* Update shared-memory copy of checkpoint XID/epoch */
-		SpinLockAcquire(&XLogCtl->info_lck);
-		XLogCtl->ckptFullXid = checkPoint.nextXid;
-		SpinLockRelease(&XLogCtl->info_lck);
-
 		/*
 		 * We should've already switched to the new TLI before replaying this
 		 * record.
@@ -8595,11 +8586,6 @@ xlog_redo(XLogReaderState *record)
 		ControlFile->checkPointCopy.nextXid = checkPoint.nextXid;
 		LWLockRelease(ControlFileLock);
 
-		/* Update shared-memory copy of checkpoint XID/epoch */
-		SpinLockAcquire(&XLogCtl->info_lck);
-		XLogCtl->ckptFullXid = checkPoint.nextXid;
-		SpinLockRelease(&XLogCtl->info_lck);
-
 		/* TLI should not change in an on-line checkpoint */
 		(void) GetCurrentReplayRecPtr(&replayTLI);
 		if (checkPoint.ThisTimeLineID != replayTLI)
@@ -8947,9 +8933,8 @@ issue_xlog_fsync(int fd, XLogSegNo segno, TimeLineID tli)
  * backup state and tablespace map.
  *
  * Input parameters are "state" (the backup state), "fast" (if true, we do
- * the checkpoint in immediate mode to make it faster), and "tablespaces"
- * (if non-NULL, indicates a list of tablespaceinfo structs describing the
- * cluster's tablespaces.).
+ * the checkpoint in fast mode), and "tablespaces" (if non-NULL, indicates a
+ * list of tablespaceinfo structs describing the cluster's tablespaces.).
  *
  * The tablespace map contents are appended to passed-in parameter
  * tablespace_map and the caller is responsible for including it in the backup
@@ -9026,7 +9011,7 @@ do_pg_backup_start(const char *backupidstr, bool fast, List **tablespaces,
 	 * work correctly, it is critical that sessionBackupState is only updated
 	 * after this block is over.
 	 */
-	PG_ENSURE_ERROR_CLEANUP(do_pg_abort_backup, DatumGetBool(true));
+	PG_ENSURE_ERROR_CLEANUP(do_pg_abort_backup, BoolGetDatum(true));
 	{
 		bool		gotUniqueStartpoint = false;
 		DIR		   *tblspcdir;
@@ -9077,11 +9062,11 @@ do_pg_backup_start(const char *backupidstr, bool fast, List **tablespaces,
 			 * during recovery means that checkpointer is running, we can use
 			 * RequestCheckpoint() to establish a restartpoint.
 			 *
-			 * We use CHECKPOINT_IMMEDIATE only if requested by user (via
-			 * passing fast = true).  Otherwise this can take awhile.
+			 * We use CHECKPOINT_FAST only if requested by user (via passing
+			 * fast = true).  Otherwise this can take awhile.
 			 */
 			RequestCheckpoint(CHECKPOINT_FORCE | CHECKPOINT_WAIT |
-							  (fast ? CHECKPOINT_IMMEDIATE : 0));
+							  (fast ? CHECKPOINT_FAST : 0));
 
 			/*
 			 * Now we need to fetch the checkpoint record location, and also
@@ -9265,7 +9250,7 @@ do_pg_backup_start(const char *backupidstr, bool fast, List **tablespaces,
 
 		state->starttime = (pg_time_t) time(NULL);
 	}
-	PG_END_ENSURE_ERROR_CLEANUP(do_pg_abort_backup, DatumGetBool(true));
+	PG_END_ENSURE_ERROR_CLEANUP(do_pg_abort_backup, BoolGetDatum(true));
 
 	state->started_in_recovery = backup_started_in_recovery;
 
@@ -9605,7 +9590,7 @@ register_persistent_abort_backup_handler(void)
 
 	if (already_done)
 		return;
-	before_shmem_exit(do_pg_abort_backup, DatumGetBool(false));
+	before_shmem_exit(do_pg_abort_backup, BoolGetDatum(false));
 	already_done = true;
 }
 
diff --git a/src/backend/access/transam/xlogbackup.c b/src/backend/access/transam/xlogbackup.c
index 342590e0a46d3..cda4b38b7d67d 100644
--- a/src/backend/access/transam/xlogbackup.c
+++ b/src/backend/access/transam/xlogbackup.c
@@ -42,7 +42,7 @@ build_backup_content(BackupState *state, bool ishistoryfile)
 
 	XLByteToSeg(state->startpoint, startsegno, wal_segment_size);
 	XLogFileName(startxlogfile, state->starttli, startsegno, wal_segment_size);
-	appendStringInfo(result, "START WAL LOCATION: %X/%X (file %s)\n",
+	appendStringInfo(result, "START WAL LOCATION: %X/%08X (file %s)\n",
 					 LSN_FORMAT_ARGS(state->startpoint), startxlogfile);
 
 	if (ishistoryfile)
@@ -52,11 +52,11 @@ build_backup_content(BackupState *state, bool ishistoryfile)
 
 		XLByteToSeg(state->stoppoint, stopsegno, wal_segment_size);
 		XLogFileName(stopxlogfile, state->stoptli, stopsegno, wal_segment_size);
-		appendStringInfo(result, "STOP WAL LOCATION: %X/%X (file %s)\n",
+		appendStringInfo(result, "STOP WAL LOCATION: %X/%08X (file %s)\n",
 						 LSN_FORMAT_ARGS(state->stoppoint), stopxlogfile);
 	}
 
-	appendStringInfo(result, "CHECKPOINT LOCATION: %X/%X\n",
+	appendStringInfo(result, "CHECKPOINT LOCATION: %X/%08X\n",
 					 LSN_FORMAT_ARGS(state->checkpointloc));
 	appendStringInfoString(result, "BACKUP METHOD: streamed\n");
 	appendStringInfo(result, "BACKUP FROM: %s\n",
@@ -81,7 +81,7 @@ build_backup_content(BackupState *state, bool ishistoryfile)
 	Assert(XLogRecPtrIsInvalid(state->istartpoint) == (state->istarttli == 0));
 	if (!XLogRecPtrIsInvalid(state->istartpoint))
 	{
-		appendStringInfo(result, "INCREMENTAL FROM LSN: %X/%X\n",
+		appendStringInfo(result, "INCREMENTAL FROM LSN: %X/%08X\n",
 						 LSN_FORMAT_ARGS(state->istartpoint));
 		appendStringInfo(result, "INCREMENTAL FROM TLI: %u\n",
 						 state->istarttli);
diff --git a/src/backend/access/transam/xloginsert.c b/src/backend/access/transam/xloginsert.c
index 5ee9d0b028eae..c7571429e8e97 100644
--- a/src/backend/access/transam/xloginsert.c
+++ b/src/backend/access/transam/xloginsert.c
@@ -529,6 +529,18 @@ XLogInsert(RmgrId rmid, uint8 info)
 	return EndPos;
 }
 
+/*
+ * Simple wrapper to XLogInsert to insert a WAL record with elementary
+ * contents (only an int64 is supported as value currently).
+ */
+XLogRecPtr
+XLogSimpleInsertInt64(RmgrId rmid, uint8 info, int64 value)
+{
+	XLogBeginInsert();
+	XLogRegisterData(&value, sizeof(value));
+	return XLogInsert(rmid, info);
+}
+
 /*
  * Assemble a WAL record from the registered data and buffers into an
  * XLogRecData chain, ready for insertion with XLogInsertRecord().
diff --git a/src/backend/access/transam/xlogprefetcher.c b/src/backend/access/transam/xlogprefetcher.c
index 7735562db01d1..ed3aacabc986e 100644
--- a/src/backend/access/transam/xlogprefetcher.c
+++ b/src/backend/access/transam/xlogprefetcher.c
@@ -546,7 +546,7 @@ XLogPrefetcherNextBlock(uintptr_t pgsr_private, XLogRecPtr *lsn)
 
 #ifdef XLOGPREFETCHER_DEBUG_LEVEL
 					elog(XLOGPREFETCHER_DEBUG_LEVEL,
-						 "suppressing all readahead until %X/%X is replayed due to possible TLI change",
+						 "suppressing all readahead until %X/%08X is replayed due to possible TLI change",
 						 LSN_FORMAT_ARGS(record->lsn));
 #endif
 
@@ -579,7 +579,7 @@ XLogPrefetcherNextBlock(uintptr_t pgsr_private, XLogRecPtr *lsn)
 
 #ifdef XLOGPREFETCHER_DEBUG_LEVEL
 					elog(XLOGPREFETCHER_DEBUG_LEVEL,
-						 "suppressing prefetch in database %u until %X/%X is replayed due to raw file copy",
+						 "suppressing prefetch in database %u until %X/%08X is replayed due to raw file copy",
 						 rlocator.dbOid,
 						 LSN_FORMAT_ARGS(record->lsn));
 #endif
@@ -607,7 +607,7 @@ XLogPrefetcherNextBlock(uintptr_t pgsr_private, XLogRecPtr *lsn)
 
 #ifdef XLOGPREFETCHER_DEBUG_LEVEL
 						elog(XLOGPREFETCHER_DEBUG_LEVEL,
-							 "suppressing prefetch in relation %u/%u/%u until %X/%X is replayed, which creates the relation",
+							 "suppressing prefetch in relation %u/%u/%u until %X/%08X is replayed, which creates the relation",
 							 xlrec->rlocator.spcOid,
 							 xlrec->rlocator.dbOid,
 							 xlrec->rlocator.relNumber,
@@ -630,7 +630,7 @@ XLogPrefetcherNextBlock(uintptr_t pgsr_private, XLogRecPtr *lsn)
 
 #ifdef XLOGPREFETCHER_DEBUG_LEVEL
 					elog(XLOGPREFETCHER_DEBUG_LEVEL,
-						 "suppressing prefetch in relation %u/%u/%u from block %u until %X/%X is replayed, which truncates the relation",
+						 "suppressing prefetch in relation %u/%u/%u from block %u until %X/%08X is replayed, which truncates the relation",
 						 xlrec->rlocator.spcOid,
 						 xlrec->rlocator.dbOid,
 						 xlrec->rlocator.relNumber,
@@ -729,7 +729,7 @@ XLogPrefetcherNextBlock(uintptr_t pgsr_private, XLogRecPtr *lsn)
 			{
 #ifdef XLOGPREFETCHER_DEBUG_LEVEL
 				elog(XLOGPREFETCHER_DEBUG_LEVEL,
-					 "suppressing all prefetch in relation %u/%u/%u until %X/%X is replayed, because the relation does not exist on disk",
+					 "suppressing all prefetch in relation %u/%u/%u until %X/%08X is replayed, because the relation does not exist on disk",
 					 reln->smgr_rlocator.locator.spcOid,
 					 reln->smgr_rlocator.locator.dbOid,
 					 reln->smgr_rlocator.locator.relNumber,
@@ -750,7 +750,7 @@ XLogPrefetcherNextBlock(uintptr_t pgsr_private, XLogRecPtr *lsn)
 			{
 #ifdef XLOGPREFETCHER_DEBUG_LEVEL
 				elog(XLOGPREFETCHER_DEBUG_LEVEL,
-					 "suppressing prefetch in relation %u/%u/%u from block %u until %X/%X is replayed, because the relation is too small",
+					 "suppressing prefetch in relation %u/%u/%u from block %u until %X/%08X is replayed, because the relation is too small",
 					 reln->smgr_rlocator.locator.spcOid,
 					 reln->smgr_rlocator.locator.dbOid,
 					 reln->smgr_rlocator.locator.relNumber,
@@ -928,7 +928,7 @@ XLogPrefetcherIsFiltered(XLogPrefetcher *prefetcher, RelFileLocator rlocator,
 		{
 #ifdef XLOGPREFETCHER_DEBUG_LEVEL
 			elog(XLOGPREFETCHER_DEBUG_LEVEL,
-				 "prefetch of %u/%u/%u block %u suppressed; filtering until LSN %X/%X is replayed (blocks >= %u filtered)",
+				 "prefetch of %u/%u/%u block %u suppressed; filtering until LSN %X/%08X is replayed (blocks >= %u filtered)",
 				 rlocator.spcOid, rlocator.dbOid, rlocator.relNumber, blockno,
 				 LSN_FORMAT_ARGS(filter->filter_until_replayed),
 				 filter->filter_from_block);
@@ -944,7 +944,7 @@ XLogPrefetcherIsFiltered(XLogPrefetcher *prefetcher, RelFileLocator rlocator,
 		{
 #ifdef XLOGPREFETCHER_DEBUG_LEVEL
 			elog(XLOGPREFETCHER_DEBUG_LEVEL,
-				 "prefetch of %u/%u/%u block %u suppressed; filtering until LSN %X/%X is replayed (whole database)",
+				 "prefetch of %u/%u/%u block %u suppressed; filtering until LSN %X/%08X is replayed (whole database)",
 				 rlocator.spcOid, rlocator.dbOid, rlocator.relNumber, blockno,
 				 LSN_FORMAT_ARGS(filter->filter_until_replayed));
 #endif
diff --git a/src/backend/access/transam/xlogreader.c b/src/backend/access/transam/xlogreader.c
index 2790ade1f91e8..dcc8d4f9c1b0b 100644
--- a/src/backend/access/transam/xlogreader.c
+++ b/src/backend/access/transam/xlogreader.c
@@ -617,7 +617,7 @@ XLogDecodeNextRecord(XLogReaderState *state, bool nonblocking)
 	}
 	else if (targetRecOff < pageHeaderSize)
 	{
-		report_invalid_record(state, "invalid record offset at %X/%X: expected at least %u, got %u",
+		report_invalid_record(state, "invalid record offset at %X/%08X: expected at least %u, got %u",
 							  LSN_FORMAT_ARGS(RecPtr),
 							  pageHeaderSize, targetRecOff);
 		goto err;
@@ -626,7 +626,7 @@ XLogDecodeNextRecord(XLogReaderState *state, bool nonblocking)
 	if ((((XLogPageHeader) state->readBuf)->xlp_info & XLP_FIRST_IS_CONTRECORD) &&
 		targetRecOff == pageHeaderSize)
 	{
-		report_invalid_record(state, "contrecord is requested by %X/%X",
+		report_invalid_record(state, "contrecord is requested by %X/%08X",
 							  LSN_FORMAT_ARGS(RecPtr));
 		goto err;
 	}
@@ -667,7 +667,7 @@ XLogDecodeNextRecord(XLogReaderState *state, bool nonblocking)
 		if (total_len < SizeOfXLogRecord)
 		{
 			report_invalid_record(state,
-								  "invalid record length at %X/%X: expected at least %u, got %u",
+								  "invalid record length at %X/%08X: expected at least %u, got %u",
 								  LSN_FORMAT_ARGS(RecPtr),
 								  (uint32) SizeOfXLogRecord, total_len);
 			goto err;
@@ -723,11 +723,12 @@ XLogDecodeNextRecord(XLogReaderState *state, bool nonblocking)
 			/* Calculate pointer to beginning of next page */
 			targetPagePtr += XLOG_BLCKSZ;
 
-			/* Wait for the next page to become available */
-			readOff = ReadPageInternal(state, targetPagePtr,
-									   Min(total_len - gotlen + SizeOfXLogShortPHD,
-										   XLOG_BLCKSZ));
-
+			/*
+			 * Read the page header before processing the record data, so we
+			 * can handle the case where the previous record ended as being a
+			 * partial one.
+			 */
+			readOff = ReadPageInternal(state, targetPagePtr, SizeOfXLogShortPHD);
 			if (readOff == XLREAD_WOULDBLOCK)
 				return XLREAD_WOULDBLOCK;
 			else if (readOff < 0)
@@ -756,7 +757,7 @@ XLogDecodeNextRecord(XLogReaderState *state, bool nonblocking)
 			if (!(pageHeader->xlp_info & XLP_FIRST_IS_CONTRECORD))
 			{
 				report_invalid_record(state,
-									  "there is no contrecord flag at %X/%X",
+									  "there is no contrecord flag at %X/%08X",
 									  LSN_FORMAT_ARGS(RecPtr));
 				goto err;
 			}
@@ -769,13 +770,22 @@ XLogDecodeNextRecord(XLogReaderState *state, bool nonblocking)
 				total_len != (pageHeader->xlp_rem_len + gotlen))
 			{
 				report_invalid_record(state,
-									  "invalid contrecord length %u (expected %lld) at %X/%X",
+									  "invalid contrecord length %u (expected %lld) at %X/%08X",
 									  pageHeader->xlp_rem_len,
 									  ((long long) total_len) - gotlen,
 									  LSN_FORMAT_ARGS(RecPtr));
 				goto err;
 			}
 
+			/* Wait for the next page to become available */
+			readOff = ReadPageInternal(state, targetPagePtr,
+									   Min(total_len - gotlen + SizeOfXLogShortPHD,
+										   XLOG_BLCKSZ));
+			if (readOff == XLREAD_WOULDBLOCK)
+				return XLREAD_WOULDBLOCK;
+			else if (readOff < 0)
+				goto err;
+
 			/* Append the continuation from this page to the buffer */
 			pageHeaderSize = XLogPageHeaderSize(pageHeader);
 
@@ -1132,7 +1142,7 @@ ValidXLogRecordHeader(XLogReaderState *state, XLogRecPtr RecPtr,
 	if (record->xl_tot_len < SizeOfXLogRecord)
 	{
 		report_invalid_record(state,
-							  "invalid record length at %X/%X: expected at least %u, got %u",
+							  "invalid record length at %X/%08X: expected at least %u, got %u",
 							  LSN_FORMAT_ARGS(RecPtr),
 							  (uint32) SizeOfXLogRecord, record->xl_tot_len);
 		return false;
@@ -1140,7 +1150,7 @@ ValidXLogRecordHeader(XLogReaderState *state, XLogRecPtr RecPtr,
 	if (!RmgrIdIsValid(record->xl_rmid))
 	{
 		report_invalid_record(state,
-							  "invalid resource manager ID %u at %X/%X",
+							  "invalid resource manager ID %u at %X/%08X",
 							  record->xl_rmid, LSN_FORMAT_ARGS(RecPtr));
 		return false;
 	}
@@ -1153,7 +1163,7 @@ ValidXLogRecordHeader(XLogReaderState *state, XLogRecPtr RecPtr,
 		if (!(record->xl_prev < RecPtr))
 		{
 			report_invalid_record(state,
-								  "record with incorrect prev-link %X/%X at %X/%X",
+								  "record with incorrect prev-link %X/%08X at %X/%08X",
 								  LSN_FORMAT_ARGS(record->xl_prev),
 								  LSN_FORMAT_ARGS(RecPtr));
 			return false;
@@ -1169,7 +1179,7 @@ ValidXLogRecordHeader(XLogReaderState *state, XLogRecPtr RecPtr,
 		if (record->xl_prev != PrevRecPtr)
 		{
 			report_invalid_record(state,
-								  "record with incorrect prev-link %X/%X at %X/%X",
+								  "record with incorrect prev-link %X/%08X at %X/%08X",
 								  LSN_FORMAT_ARGS(record->xl_prev),
 								  LSN_FORMAT_ARGS(RecPtr));
 			return false;
@@ -1207,7 +1217,7 @@ ValidXLogRecord(XLogReaderState *state, XLogRecord *record, XLogRecPtr recptr)
 	if (!EQ_CRC32C(record->xl_crc, crc))
 	{
 		report_invalid_record(state,
-							  "incorrect resource manager data checksum in record at %X/%X",
+							  "incorrect resource manager data checksum in record at %X/%08X",
 							  LSN_FORMAT_ARGS(recptr));
 		return false;
 	}
@@ -1241,7 +1251,7 @@ XLogReaderValidatePageHeader(XLogReaderState *state, XLogRecPtr recptr,
 		XLogFileName(fname, state->seg.ws_tli, segno, state->segcxt.ws_segsize);
 
 		report_invalid_record(state,
-							  "invalid magic number %04X in WAL segment %s, LSN %X/%X, offset %u",
+							  "invalid magic number %04X in WAL segment %s, LSN %X/%08X, offset %u",
 							  hdr->xlp_magic,
 							  fname,
 							  LSN_FORMAT_ARGS(recptr),
@@ -1256,7 +1266,7 @@ XLogReaderValidatePageHeader(XLogReaderState *state, XLogRecPtr recptr,
 		XLogFileName(fname, state->seg.ws_tli, segno, state->segcxt.ws_segsize);
 
 		report_invalid_record(state,
-							  "invalid info bits %04X in WAL segment %s, LSN %X/%X, offset %u",
+							  "invalid info bits %04X in WAL segment %s, LSN %X/%08X, offset %u",
 							  hdr->xlp_info,
 							  fname,
 							  LSN_FORMAT_ARGS(recptr),
@@ -1298,7 +1308,7 @@ XLogReaderValidatePageHeader(XLogReaderState *state, XLogRecPtr recptr,
 
 		/* hmm, first page of file doesn't have a long header? */
 		report_invalid_record(state,
-							  "invalid info bits %04X in WAL segment %s, LSN %X/%X, offset %u",
+							  "invalid info bits %04X in WAL segment %s, LSN %X/%08X, offset %u",
 							  hdr->xlp_info,
 							  fname,
 							  LSN_FORMAT_ARGS(recptr),
@@ -1318,7 +1328,7 @@ XLogReaderValidatePageHeader(XLogReaderState *state, XLogRecPtr recptr,
 		XLogFileName(fname, state->seg.ws_tli, segno, state->segcxt.ws_segsize);
 
 		report_invalid_record(state,
-							  "unexpected pageaddr %X/%X in WAL segment %s, LSN %X/%X, offset %u",
+							  "unexpected pageaddr %X/%08X in WAL segment %s, LSN %X/%08X, offset %u",
 							  LSN_FORMAT_ARGS(hdr->xlp_pageaddr),
 							  fname,
 							  LSN_FORMAT_ARGS(recptr),
@@ -1344,7 +1354,7 @@ XLogReaderValidatePageHeader(XLogReaderState *state, XLogRecPtr recptr,
 			XLogFileName(fname, state->seg.ws_tli, segno, state->segcxt.ws_segsize);
 
 			report_invalid_record(state,
-								  "out-of-sequence timeline ID %u (after %u) in WAL segment %s, LSN %X/%X, offset %u",
+								  "out-of-sequence timeline ID %u (after %u) in WAL segment %s, LSN %X/%08X, offset %u",
 								  hdr->xlp_tli,
 								  state->latestPageTLI,
 								  fname,
@@ -1756,7 +1766,7 @@ DecodeXLogRecord(XLogReaderState *state,
 			if (block_id <= decoded->max_block_id)
 			{
 				report_invalid_record(state,
-									  "out-of-order block_id %u at %X/%X",
+									  "out-of-order block_id %u at %X/%08X",
 									  block_id,
 									  LSN_FORMAT_ARGS(state->ReadRecPtr));
 				goto err;
@@ -1780,14 +1790,14 @@ DecodeXLogRecord(XLogReaderState *state,
 			if (blk->has_data && blk->data_len == 0)
 			{
 				report_invalid_record(state,
-									  "BKPBLOCK_HAS_DATA set, but no data included at %X/%X",
+									  "BKPBLOCK_HAS_DATA set, but no data included at %X/%08X",
 									  LSN_FORMAT_ARGS(state->ReadRecPtr));
 				goto err;
 			}
 			if (!blk->has_data && blk->data_len != 0)
 			{
 				report_invalid_record(state,
-									  "BKPBLOCK_HAS_DATA not set, but data length is %u at %X/%X",
+									  "BKPBLOCK_HAS_DATA not set, but data length is %u at %X/%08X",
 									  (unsigned int) blk->data_len,
 									  LSN_FORMAT_ARGS(state->ReadRecPtr));
 				goto err;
@@ -1823,7 +1833,7 @@ DecodeXLogRecord(XLogReaderState *state,
 					 blk->bimg_len == BLCKSZ))
 				{
 					report_invalid_record(state,
-										  "BKPIMAGE_HAS_HOLE set, but hole offset %u length %u block image length %u at %X/%X",
+										  "BKPIMAGE_HAS_HOLE set, but hole offset %u length %u block image length %u at %X/%08X",
 										  (unsigned int) blk->hole_offset,
 										  (unsigned int) blk->hole_length,
 										  (unsigned int) blk->bimg_len,
@@ -1839,7 +1849,7 @@ DecodeXLogRecord(XLogReaderState *state,
 					(blk->hole_offset != 0 || blk->hole_length != 0))
 				{
 					report_invalid_record(state,
-										  "BKPIMAGE_HAS_HOLE not set, but hole offset %u length %u at %X/%X",
+										  "BKPIMAGE_HAS_HOLE not set, but hole offset %u length %u at %X/%08X",
 										  (unsigned int) blk->hole_offset,
 										  (unsigned int) blk->hole_length,
 										  LSN_FORMAT_ARGS(state->ReadRecPtr));
@@ -1853,7 +1863,7 @@ DecodeXLogRecord(XLogReaderState *state,
 					blk->bimg_len == BLCKSZ)
 				{
 					report_invalid_record(state,
-										  "BKPIMAGE_COMPRESSED set, but block image length %u at %X/%X",
+										  "BKPIMAGE_COMPRESSED set, but block image length %u at %X/%08X",
 										  (unsigned int) blk->bimg_len,
 										  LSN_FORMAT_ARGS(state->ReadRecPtr));
 					goto err;
@@ -1868,7 +1878,7 @@ DecodeXLogRecord(XLogReaderState *state,
 					blk->bimg_len != BLCKSZ)
 				{
 					report_invalid_record(state,
-										  "neither BKPIMAGE_HAS_HOLE nor BKPIMAGE_COMPRESSED set, but block image length is %u at %X/%X",
+										  "neither BKPIMAGE_HAS_HOLE nor BKPIMAGE_COMPRESSED set, but block image length is %u at %X/%08X",
 										  (unsigned int) blk->data_len,
 										  LSN_FORMAT_ARGS(state->ReadRecPtr));
 					goto err;
@@ -1884,7 +1894,7 @@ DecodeXLogRecord(XLogReaderState *state,
 				if (rlocator == NULL)
 				{
 					report_invalid_record(state,
-										  "BKPBLOCK_SAME_REL set but no previous rel at %X/%X",
+										  "BKPBLOCK_SAME_REL set but no previous rel at %X/%08X",
 										  LSN_FORMAT_ARGS(state->ReadRecPtr));
 					goto err;
 				}
@@ -1896,7 +1906,7 @@ DecodeXLogRecord(XLogReaderState *state,
 		else
 		{
 			report_invalid_record(state,
-								  "invalid block_id %u at %X/%X",
+								  "invalid block_id %u at %X/%08X",
 								  block_id, LSN_FORMAT_ARGS(state->ReadRecPtr));
 			goto err;
 		}
@@ -1963,7 +1973,7 @@ DecodeXLogRecord(XLogReaderState *state,
 
 shortdata_err:
 	report_invalid_record(state,
-						  "record with invalid length at %X/%X",
+						  "record with invalid length at %X/%08X",
 						  LSN_FORMAT_ARGS(state->ReadRecPtr));
 err:
 	*errormsg = state->errormsg_buf;
@@ -2073,14 +2083,14 @@ RestoreBlockImage(XLogReaderState *record, uint8 block_id, char *page)
 		!record->record->blocks[block_id].in_use)
 	{
 		report_invalid_record(record,
-							  "could not restore image at %X/%X with invalid block %d specified",
+							  "could not restore image at %X/%08X with invalid block %d specified",
 							  LSN_FORMAT_ARGS(record->ReadRecPtr),
 							  block_id);
 		return false;
 	}
 	if (!record->record->blocks[block_id].has_image)
 	{
-		report_invalid_record(record, "could not restore image at %X/%X with invalid state, block %d",
+		report_invalid_record(record, "could not restore image at %X/%08X with invalid state, block %d",
 							  LSN_FORMAT_ARGS(record->ReadRecPtr),
 							  block_id);
 		return false;
@@ -2107,7 +2117,7 @@ RestoreBlockImage(XLogReaderState *record, uint8 block_id, char *page)
 									bkpb->bimg_len, BLCKSZ - bkpb->hole_length) <= 0)
 				decomp_success = false;
 #else
-			report_invalid_record(record, "could not restore image at %X/%X compressed with %s not supported by build, block %d",
+			report_invalid_record(record, "could not restore image at %X/%08X compressed with %s not supported by build, block %d",
 								  LSN_FORMAT_ARGS(record->ReadRecPtr),
 								  "LZ4",
 								  block_id);
@@ -2124,7 +2134,7 @@ RestoreBlockImage(XLogReaderState *record, uint8 block_id, char *page)
 			if (ZSTD_isError(decomp_result))
 				decomp_success = false;
 #else
-			report_invalid_record(record, "could not restore image at %X/%X compressed with %s not supported by build, block %d",
+			report_invalid_record(record, "could not restore image at %X/%08X compressed with %s not supported by build, block %d",
 								  LSN_FORMAT_ARGS(record->ReadRecPtr),
 								  "zstd",
 								  block_id);
@@ -2133,7 +2143,7 @@ RestoreBlockImage(XLogReaderState *record, uint8 block_id, char *page)
 		}
 		else
 		{
-			report_invalid_record(record, "could not restore image at %X/%X compressed with unknown method, block %d",
+			report_invalid_record(record, "could not restore image at %X/%08X compressed with unknown method, block %d",
 								  LSN_FORMAT_ARGS(record->ReadRecPtr),
 								  block_id);
 			return false;
@@ -2141,7 +2151,7 @@ RestoreBlockImage(XLogReaderState *record, uint8 block_id, char *page)
 
 		if (!decomp_success)
 		{
-			report_invalid_record(record, "could not decompress image at %X/%X, block %d",
+			report_invalid_record(record, "could not decompress image at %X/%08X, block %d",
 								  LSN_FORMAT_ARGS(record->ReadRecPtr),
 								  block_id);
 			return false;
diff --git a/src/backend/access/transam/xlogrecovery.c b/src/backend/access/transam/xlogrecovery.c
index 6ce979f2d8bc4..f23ec8969c27d 100644
--- a/src/backend/access/transam/xlogrecovery.c
+++ b/src/backend/access/transam/xlogrecovery.c
@@ -620,10 +620,10 @@ InitWalRecovery(ControlFileData *ControlFile, bool *wasShutdown_ptr,
 		 * than ControlFile->checkPoint is used.
 		 */
 		ereport(LOG,
-				(errmsg("starting backup recovery with redo LSN %X/%X, checkpoint LSN %X/%X, on timeline ID %u",
-						LSN_FORMAT_ARGS(RedoStartLSN),
-						LSN_FORMAT_ARGS(CheckPointLoc),
-						CheckPointTLI)));
+				errmsg("starting backup recovery with redo LSN %X/%08X, checkpoint LSN %X/%08X, on timeline ID %u",
+					   LSN_FORMAT_ARGS(RedoStartLSN),
+					   LSN_FORMAT_ARGS(CheckPointLoc),
+					   CheckPointTLI));
 
 		/*
 		 * When a backup_label file is present, we want to roll forward from
@@ -636,8 +636,8 @@ InitWalRecovery(ControlFileData *ControlFile, bool *wasShutdown_ptr,
 			memcpy(&checkPoint, XLogRecGetData(xlogreader), sizeof(CheckPoint));
 			wasShutdown = ((record->xl_info & ~XLR_INFO_MASK) == XLOG_CHECKPOINT_SHUTDOWN);
 			ereport(DEBUG1,
-					(errmsg_internal("checkpoint record is at %X/%X",
-									 LSN_FORMAT_ARGS(CheckPointLoc))));
+					errmsg_internal("checkpoint record is at %X/%08X",
+									LSN_FORMAT_ARGS(CheckPointLoc)));
 			InRecovery = true;	/* force recovery even if SHUTDOWNED */
 
 			/*
@@ -652,23 +652,23 @@ InitWalRecovery(ControlFileData *ControlFile, bool *wasShutdown_ptr,
 				if (!ReadRecord(xlogprefetcher, LOG, false,
 								checkPoint.ThisTimeLineID))
 					ereport(FATAL,
-							(errmsg("could not find redo location %X/%X referenced by checkpoint record at %X/%X",
-									LSN_FORMAT_ARGS(checkPoint.redo), LSN_FORMAT_ARGS(CheckPointLoc)),
-							 errhint("If you are restoring from a backup, touch \"%s/recovery.signal\" or \"%s/standby.signal\" and add required recovery options.\n"
-									 "If you are not restoring from a backup, try removing the file \"%s/backup_label\".\n"
-									 "Be careful: removing \"%s/backup_label\" will result in a corrupt cluster if restoring from a backup.",
-									 DataDir, DataDir, DataDir, DataDir)));
+							errmsg("could not find redo location %X/%08X referenced by checkpoint record at %X/%08X",
+								   LSN_FORMAT_ARGS(checkPoint.redo), LSN_FORMAT_ARGS(CheckPointLoc)),
+							errhint("If you are restoring from a backup, touch \"%s/recovery.signal\" or \"%s/standby.signal\" and add required recovery options.\n"
+									"If you are not restoring from a backup, try removing the file \"%s/backup_label\".\n"
+									"Be careful: removing \"%s/backup_label\" will result in a corrupt cluster if restoring from a backup.",
+									DataDir, DataDir, DataDir, DataDir));
 			}
 		}
 		else
 		{
 			ereport(FATAL,
-					(errmsg("could not locate required checkpoint record at %X/%X",
-							LSN_FORMAT_ARGS(CheckPointLoc)),
-					 errhint("If you are restoring from a backup, touch \"%s/recovery.signal\" or \"%s/standby.signal\" and add required recovery options.\n"
-							 "If you are not restoring from a backup, try removing the file \"%s/backup_label\".\n"
-							 "Be careful: removing \"%s/backup_label\" will result in a corrupt cluster if restoring from a backup.",
-							 DataDir, DataDir, DataDir, DataDir)));
+					errmsg("could not locate required checkpoint record at %X/%08X",
+						   LSN_FORMAT_ARGS(CheckPointLoc)),
+					errhint("If you are restoring from a backup, touch \"%s/recovery.signal\" or \"%s/standby.signal\" and add required recovery options.\n"
+							"If you are not restoring from a backup, try removing the file \"%s/backup_label\".\n"
+							"Be careful: removing \"%s/backup_label\" will result in a corrupt cluster if restoring from a backup.",
+							DataDir, DataDir, DataDir, DataDir));
 			wasShutdown = false;	/* keep compiler quiet */
 		}
 
@@ -773,8 +773,8 @@ InitWalRecovery(ControlFileData *ControlFile, bool *wasShutdown_ptr,
 		 */
 		if (!XLogRecPtrIsInvalid(ControlFile->backupStartPoint))
 			ereport(LOG,
-					(errmsg("restarting backup recovery with redo LSN %X/%X",
-							LSN_FORMAT_ARGS(ControlFile->backupStartPoint))));
+					errmsg("restarting backup recovery with redo LSN %X/%08X",
+						   LSN_FORMAT_ARGS(ControlFile->backupStartPoint)));
 
 		/* Get the last valid checkpoint record. */
 		CheckPointLoc = ControlFile->checkPoint;
@@ -786,8 +786,8 @@ InitWalRecovery(ControlFileData *ControlFile, bool *wasShutdown_ptr,
 		if (record != NULL)
 		{
 			ereport(DEBUG1,
-					(errmsg_internal("checkpoint record is at %X/%X",
-									 LSN_FORMAT_ARGS(CheckPointLoc))));
+					errmsg_internal("checkpoint record is at %X/%08X",
+									LSN_FORMAT_ARGS(CheckPointLoc)));
 		}
 		else
 		{
@@ -798,8 +798,8 @@ InitWalRecovery(ControlFileData *ControlFile, bool *wasShutdown_ptr,
 			 * simplify processing around checkpoints.
 			 */
 			ereport(PANIC,
-					(errmsg("could not locate a valid checkpoint record at %X/%X",
-							LSN_FORMAT_ARGS(CheckPointLoc))));
+					errmsg("could not locate a valid checkpoint record at %X/%08X",
+						   LSN_FORMAT_ARGS(CheckPointLoc)));
 		}
 		memcpy(&checkPoint, XLogRecGetData(xlogreader), sizeof(CheckPoint));
 		wasShutdown = ((record->xl_info & ~XLR_INFO_MASK) == XLOG_CHECKPOINT_SHUTDOWN);
@@ -824,8 +824,8 @@ InitWalRecovery(ControlFileData *ControlFile, bool *wasShutdown_ptr,
 							recoveryTargetName)));
 		else if (recoveryTarget == RECOVERY_TARGET_LSN)
 			ereport(LOG,
-					(errmsg("starting point-in-time recovery to WAL location (LSN) \"%X/%X\"",
-							LSN_FORMAT_ARGS(recoveryTargetLSN))));
+					errmsg("starting point-in-time recovery to WAL location (LSN) \"%X/%08X\"",
+						   LSN_FORMAT_ARGS(recoveryTargetLSN)));
 		else if (recoveryTarget == RECOVERY_TARGET_IMMEDIATE)
 			ereport(LOG,
 					(errmsg("starting point-in-time recovery to earliest consistent point")));
@@ -855,7 +855,7 @@ InitWalRecovery(ControlFileData *ControlFile, bool *wasShutdown_ptr,
 				(errmsg("requested timeline %u is not a child of this server's history",
 						recoveryTargetTLI),
 		/* translator: %s is a backup_label file or a pg_control file */
-				 errdetail("Latest checkpoint in file \"%s\" is at %X/%X on timeline %u, but in the history of the requested timeline, the server forked off from that timeline at %X/%X.",
+				 errdetail("Latest checkpoint in file \"%s\" is at %X/%08X on timeline %u, but in the history of the requested timeline, the server forked off from that timeline at %X/%08X.",
 						   haveBackupLabel ? "backup_label" : "pg_control",
 						   LSN_FORMAT_ARGS(CheckPointLoc),
 						   CheckPointTLI,
@@ -870,15 +870,15 @@ InitWalRecovery(ControlFileData *ControlFile, bool *wasShutdown_ptr,
 		tliOfPointInHistory(ControlFile->minRecoveryPoint - 1, expectedTLEs) !=
 		ControlFile->minRecoveryPointTLI)
 		ereport(FATAL,
-				(errmsg("requested timeline %u does not contain minimum recovery point %X/%X on timeline %u",
-						recoveryTargetTLI,
-						LSN_FORMAT_ARGS(ControlFile->minRecoveryPoint),
-						ControlFile->minRecoveryPointTLI)));
+				errmsg("requested timeline %u does not contain minimum recovery point %X/%08X on timeline %u",
+					   recoveryTargetTLI,
+					   LSN_FORMAT_ARGS(ControlFile->minRecoveryPoint),
+					   ControlFile->minRecoveryPointTLI));
 
 	ereport(DEBUG1,
-			(errmsg_internal("redo record is at %X/%X; shutdown %s",
-							 LSN_FORMAT_ARGS(checkPoint.redo),
-							 wasShutdown ? "true" : "false")));
+			errmsg_internal("redo record is at %X/%08X; shutdown %s",
+							LSN_FORMAT_ARGS(checkPoint.redo),
+							wasShutdown ? "true" : "false"));
 	ereport(DEBUG1,
 			(errmsg_internal("next transaction ID: " UINT64_FORMAT "; next OID: %u",
 							 U64FromFullTransactionId(checkPoint.nextXid),
@@ -1253,14 +1253,14 @@ read_backup_label(XLogRecPtr *checkPointLoc, TimeLineID *backupLabelTLI,
 	 * is pretty crude, but we are not expecting any variability in the file
 	 * format).
 	 */
-	if (fscanf(lfp, "START WAL LOCATION: %X/%X (file %08X%16s)%c",
+	if (fscanf(lfp, "START WAL LOCATION: %X/%08X (file %08X%16s)%c",
 			   &hi, &lo, &tli_from_walseg, startxlogfilename, &ch) != 5 || ch != '\n')
 		ereport(FATAL,
 				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
 				 errmsg("invalid data in file \"%s\"", BACKUP_LABEL_FILE)));
 	RedoStartLSN = ((uint64) hi) << 32 | lo;
 	RedoStartTLI = tli_from_walseg;
-	if (fscanf(lfp, "CHECKPOINT LOCATION: %X/%X%c",
+	if (fscanf(lfp, "CHECKPOINT LOCATION: %X/%08X%c",
 			   &hi, &lo, &ch) != 3 || ch != '\n')
 		ereport(FATAL,
 				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
@@ -1332,7 +1332,7 @@ read_backup_label(XLogRecPtr *checkPointLoc, TimeLineID *backupLabelTLI,
 								 tli_from_file, BACKUP_LABEL_FILE)));
 	}
 
-	if (fscanf(lfp, "INCREMENTAL FROM LSN: %X/%X\n", &hi, &lo) > 0)
+	if (fscanf(lfp, "INCREMENTAL FROM LSN: %X/%08X\n", &hi, &lo) > 0)
 		ereport(FATAL,
 				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
 				 errmsg("this is an incremental backup, not a data directory"),
@@ -1626,6 +1626,7 @@ ShutdownWalRecovery(void)
 		close(readFile);
 		readFile = -1;
 	}
+	pfree(xlogreader->private_data);
 	XLogReaderFree(xlogreader);
 	XLogPrefetcherFree(xlogprefetcher);
 
@@ -1722,8 +1723,8 @@ PerformWalRecovery(void)
 		if (record->xl_rmid != RM_XLOG_ID ||
 			(record->xl_info & ~XLR_INFO_MASK) != XLOG_CHECKPOINT_REDO)
 			ereport(FATAL,
-					(errmsg("unexpected record type found at redo point %X/%X",
-							LSN_FORMAT_ARGS(xlogreader->ReadRecPtr))));
+					errmsg("unexpected record type found at redo point %X/%08X",
+						   LSN_FORMAT_ARGS(xlogreader->ReadRecPtr)));
 	}
 	else
 	{
@@ -1745,8 +1746,8 @@ PerformWalRecovery(void)
 		RmgrStartup();
 
 		ereport(LOG,
-				(errmsg("redo starts at %X/%X",
-						LSN_FORMAT_ARGS(xlogreader->ReadRecPtr))));
+				errmsg("redo starts at %X/%08X",
+					   LSN_FORMAT_ARGS(xlogreader->ReadRecPtr)));
 
 		/* Prepare to report progress of the redo phase. */
 		if (!StandbyMode)
@@ -1758,7 +1759,7 @@ PerformWalRecovery(void)
 		do
 		{
 			if (!StandbyMode)
-				ereport_startup_progress("redo in progress, elapsed time: %ld.%02d s, current LSN: %X/%X",
+				ereport_startup_progress("redo in progress, elapsed time: %ld.%02d s, current LSN: %X/%08X",
 										 LSN_FORMAT_ARGS(xlogreader->ReadRecPtr));
 
 #ifdef WAL_DEBUG
@@ -1767,7 +1768,7 @@ PerformWalRecovery(void)
 				StringInfoData buf;
 
 				initStringInfo(&buf);
-				appendStringInfo(&buf, "REDO @ %X/%X; LSN %X/%X: ",
+				appendStringInfo(&buf, "REDO @ %X/%08X; LSN %X/%08X: ",
 								 LSN_FORMAT_ARGS(xlogreader->ReadRecPtr),
 								 LSN_FORMAT_ARGS(xlogreader->EndRecPtr));
 				xlog_outrec(&buf, xlogreader);
@@ -1880,9 +1881,9 @@ PerformWalRecovery(void)
 		RmgrCleanup();
 
 		ereport(LOG,
-				(errmsg("redo done at %X/%X system usage: %s",
-						LSN_FORMAT_ARGS(xlogreader->ReadRecPtr),
-						pg_rusage_show(&ru0))));
+				errmsg("redo done at %X/%08X system usage: %s",
+					   LSN_FORMAT_ARGS(xlogreader->ReadRecPtr),
+					   pg_rusage_show(&ru0)));
 		xtime = GetLatestXTime();
 		if (xtime)
 			ereport(LOG,
@@ -2092,7 +2093,7 @@ xlogrecovery_redo(XLogReaderState *record, TimeLineID replayTLI)
 
 		memcpy(&xlrec, XLogRecGetData(record), sizeof(xl_overwrite_contrecord));
 		if (xlrec.overwritten_lsn != record->overwrittenRecPtr)
-			elog(FATAL, "mismatching overwritten LSN %X/%X -> %X/%X",
+			elog(FATAL, "mismatching overwritten LSN %X/%08X -> %X/%08X",
 				 LSN_FORMAT_ARGS(xlrec.overwritten_lsn),
 				 LSN_FORMAT_ARGS(record->overwrittenRecPtr));
 
@@ -2101,9 +2102,9 @@ xlogrecovery_redo(XLogReaderState *record, TimeLineID replayTLI)
 		missingContrecPtr = InvalidXLogRecPtr;
 
 		ereport(LOG,
-				(errmsg("successfully skipped missing contrecord at %X/%X, overwritten at %s",
-						LSN_FORMAT_ARGS(xlrec.overwritten_lsn),
-						timestamptz_to_str(xlrec.overwrite_time))));
+				errmsg("successfully skipped missing contrecord at %X/%08X, overwritten at %s",
+					   LSN_FORMAT_ARGS(xlrec.overwritten_lsn),
+					   timestamptz_to_str(xlrec.overwrite_time)));
 
 		/* Verifying the record should only happen once */
 		record->overwrittenRecPtr = InvalidXLogRecPtr;
@@ -2129,7 +2130,7 @@ xlogrecovery_redo(XLogReaderState *record, TimeLineID replayTLI)
 			backupEndPoint = lsn;
 		}
 		else
-			elog(DEBUG1, "saw end-of-backup record for backup starting at %X/%X, waiting for %X/%X",
+			elog(DEBUG1, "saw end-of-backup record for backup starting at %X/%08X, waiting for %X/%08X",
 				 LSN_FORMAT_ARGS(startpoint), LSN_FORMAT_ARGS(backupStartPoint));
 	}
 }
@@ -2224,9 +2225,9 @@ CheckRecoveryConsistency(void)
 		backupEndRequired = false;
 
 		ereport(LOG,
-				(errmsg("completed backup recovery with redo LSN %X/%X and end LSN %X/%X",
-						LSN_FORMAT_ARGS(saveBackupStartPoint),
-						LSN_FORMAT_ARGS(saveBackupEndPoint))));
+				errmsg("completed backup recovery with redo LSN %X/%08X and end LSN %X/%08X",
+					   LSN_FORMAT_ARGS(saveBackupStartPoint),
+					   LSN_FORMAT_ARGS(saveBackupEndPoint)));
 	}
 
 	/*
@@ -2255,8 +2256,8 @@ CheckRecoveryConsistency(void)
 		reachedConsistency = true;
 		SendPostmasterSignal(PMSIGNAL_RECOVERY_CONSISTENT);
 		ereport(LOG,
-				(errmsg("consistent recovery state reached at %X/%X",
-						LSN_FORMAT_ARGS(lastReplayedEndRecPtr))));
+				errmsg("consistent recovery state reached at %X/%08X",
+					   LSN_FORMAT_ARGS(lastReplayedEndRecPtr)));
 	}
 
 	/*
@@ -2293,7 +2294,7 @@ rm_redo_error_callback(void *arg)
 	xlog_block_info(&buf, record);
 
 	/* translator: %s is a WAL record description */
-	errcontext("WAL redo at %X/%X for %s",
+	errcontext("WAL redo at %X/%08X for %s",
 			   LSN_FORMAT_ARGS(record->ReadRecPtr),
 			   buf.data);
 
@@ -2328,7 +2329,7 @@ xlog_outdesc(StringInfo buf, XLogReaderState *record)
 static void
 xlog_outrec(StringInfo buf, XLogReaderState *record)
 {
-	appendStringInfo(buf, "prev %X/%X; xid %u",
+	appendStringInfo(buf, "prev %X/%08X; xid %u",
 					 LSN_FORMAT_ARGS(XLogRecGetPrev(record)),
 					 XLogRecGetXid(record));
 
@@ -2416,10 +2417,10 @@ checkTimeLineSwitch(XLogRecPtr lsn, TimeLineID newTLI, TimeLineID prevTLI,
 		lsn < minRecoveryPoint &&
 		newTLI > minRecoveryPointTLI)
 		ereport(PANIC,
-				(errmsg("unexpected timeline ID %u in checkpoint record, before reaching minimum recovery point %X/%X on timeline %u",
-						newTLI,
-						LSN_FORMAT_ARGS(minRecoveryPoint),
-						minRecoveryPointTLI)));
+				errmsg("unexpected timeline ID %u in checkpoint record, before reaching minimum recovery point %X/%08X on timeline %u",
+					   newTLI,
+					   LSN_FORMAT_ARGS(minRecoveryPoint),
+					   minRecoveryPointTLI));
 
 	/* Looks good */
 }
@@ -2621,8 +2622,8 @@ recoveryStopsBefore(XLogReaderState *record)
 		recoveryStopTime = 0;
 		recoveryStopName[0] = '\0';
 		ereport(LOG,
-				(errmsg("recovery stopping before WAL location (LSN) \"%X/%X\"",
-						LSN_FORMAT_ARGS(recoveryStopLSN))));
+				errmsg("recovery stopping before WAL location (LSN) \"%X/%08X\"",
+					   LSN_FORMAT_ARGS(recoveryStopLSN)));
 		return true;
 	}
 
@@ -2789,8 +2790,8 @@ recoveryStopsAfter(XLogReaderState *record)
 		recoveryStopTime = 0;
 		recoveryStopName[0] = '\0';
 		ereport(LOG,
-				(errmsg("recovery stopping after WAL location (LSN) \"%X/%X\"",
-						LSN_FORMAT_ARGS(recoveryStopLSN))));
+				errmsg("recovery stopping after WAL location (LSN) \"%X/%08X\"",
+					   LSN_FORMAT_ARGS(recoveryStopLSN)));
 		return true;
 	}
 
@@ -2910,7 +2911,7 @@ getRecoveryStopReason(void)
 				 timestamptz_to_str(recoveryStopTime));
 	else if (recoveryTarget == RECOVERY_TARGET_LSN)
 		snprintf(reason, sizeof(reason),
-				 "%s LSN %X/%X\n",
+				 "%s LSN %X/%08X\n",
 				 recoveryStopAfter ? "after" : "before",
 				 LSN_FORMAT_ARGS(recoveryStopLSN));
 	else if (recoveryTarget == RECOVERY_TARGET_NAME)
@@ -3213,11 +3214,11 @@ ReadRecord(XLogPrefetcher *xlogprefetcher, int emode,
 			XLogFileName(fname, xlogreader->seg.ws_tli, segno,
 						 wal_segment_size);
 			ereport(emode_for_corrupt_record(emode, xlogreader->EndRecPtr),
-					(errmsg("unexpected timeline ID %u in WAL segment %s, LSN %X/%X, offset %u",
-							xlogreader->latestPageTLI,
-							fname,
-							LSN_FORMAT_ARGS(xlogreader->latestPagePtr),
-							offset)));
+					errmsg("unexpected timeline ID %u in WAL segment %s, LSN %X/%08X, offset %u",
+						   xlogreader->latestPageTLI,
+						   fname,
+						   LSN_FORMAT_ARGS(xlogreader->latestPagePtr),
+						   offset));
 			record = NULL;
 		}
 
@@ -3429,14 +3430,14 @@ XLogPageRead(XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, int reqLen,
 			errno = save_errno;
 			ereport(emode_for_corrupt_record(emode, targetPagePtr + reqLen),
 					(errcode_for_file_access(),
-					 errmsg("could not read from WAL segment %s, LSN %X/%X, offset %u: %m",
+					 errmsg("could not read from WAL segment %s, LSN %X/%08X, offset %u: %m",
 							fname, LSN_FORMAT_ARGS(targetPagePtr),
 							readOff)));
 		}
 		else
 			ereport(emode_for_corrupt_record(emode, targetPagePtr + reqLen),
 					(errcode(ERRCODE_DATA_CORRUPTED),
-					 errmsg("could not read from WAL segment %s, LSN %X/%X, offset %u: read %d of %zu",
+					 errmsg("could not read from WAL segment %s, LSN %X/%08X, offset %u: read %d of %zu",
 							fname, LSN_FORMAT_ARGS(targetPagePtr),
 							readOff, r, (Size) XLOG_BLCKSZ)));
 		goto next_record_is_invalid;
@@ -3718,7 +3719,7 @@ WaitForWALToBecomeAvailable(XLogRecPtr RecPtr, bool randAccess,
 						wait_time = wal_retrieve_retry_interval -
 							TimestampDifferenceMilliseconds(last_fail_time, now);
 
-						elog(LOG, "waiting for WAL to become available at %X/%X",
+						elog(LOG, "waiting for WAL to become available at %X/%08X",
 							 LSN_FORMAT_ARGS(RecPtr));
 
 						/* Do background tasks that might benefit us later. */
@@ -3864,7 +3865,7 @@ WaitForWALToBecomeAvailable(XLogRecPtr RecPtr, bool randAccess,
 							tli = tliOfPointInHistory(tliRecPtr, expectedTLEs);
 
 							if (curFileTLI > 0 && tli < curFileTLI)
-								elog(ERROR, "according to history file, WAL location %X/%X belongs to timeline %u, but previous recovered WAL file came from timeline %u",
+								elog(ERROR, "according to history file, WAL location %X/%08X belongs to timeline %u, but previous recovered WAL file came from timeline %u",
 									 LSN_FORMAT_ARGS(tliRecPtr),
 									 tli, curFileTLI);
 						}
@@ -4177,10 +4178,10 @@ rescanLatestTimeLine(TimeLineID replayTLI, XLogRecPtr replayLSN)
 	if (currentTle->end < replayLSN)
 	{
 		ereport(LOG,
-				(errmsg("new timeline %u forked off current database system timeline %u before current recovery point %X/%X",
-						newtarget,
-						replayTLI,
-						LSN_FORMAT_ARGS(replayLSN))));
+				errmsg("new timeline %u forked off current database system timeline %u before current recovery point %X/%08X",
+					   newtarget,
+					   replayTLI,
+					   LSN_FORMAT_ARGS(replayLSN)));
 		return false;
 	}
 
@@ -4760,7 +4761,7 @@ bool
 check_primary_slot_name(char **newval, void **extra, GucSource source)
 {
 	if (*newval && strcmp(*newval, "") != 0 &&
-		!ReplicationSlotValidateName(*newval, WARNING))
+		!ReplicationSlotValidateName(*newval, false, WARNING))
 		return false;
 
 	return true;
@@ -4994,13 +4995,25 @@ check_recovery_target_timeline(char **newval, void **extra, GucSource source)
 		rttg = RECOVERY_TARGET_TIMELINE_LATEST;
 	else
 	{
+		char	   *endp;
+		uint64		timeline;
+
 		rttg = RECOVERY_TARGET_TIMELINE_NUMERIC;
 
 		errno = 0;
-		strtoul(*newval, NULL, 0);
-		if (errno == EINVAL || errno == ERANGE)
+		timeline = strtou64(*newval, &endp, 0);
+
+		if (*endp != '\0' || errno == EINVAL || errno == ERANGE)
+		{
+			GUC_check_errdetail("\"%s\" is not a valid number.",
+								"recovery_target_timeline");
+			return false;
+		}
+
+		if (timeline < 1 || timeline > PG_UINT32_MAX)
 		{
-			GUC_check_errdetail("\"recovery_target_timeline\" is not a valid number.");
+			GUC_check_errdetail("\"%s\" must be between %u and %u.",
+								"recovery_target_timeline", 1, UINT_MAX);
 			return false;
 		}
 	}
diff --git a/src/backend/access/transam/xlogutils.c b/src/backend/access/transam/xlogutils.c
index c389b27f77d47..27ea52fdfee66 100644
--- a/src/backend/access/transam/xlogutils.c
+++ b/src/backend/access/transam/xlogutils.c
@@ -795,7 +795,7 @@ XLogReadDetermineTimeline(XLogReaderState *state, XLogRecPtr wantPage,
 
 		list_free_deep(timelineHistory);
 
-		elog(DEBUG3, "switched to timeline %u valid until %X/%X",
+		elog(DEBUG3, "switched to timeline %u valid until %X/%08X",
 			 state->currTLI,
 			 LSN_FORMAT_ARGS(state->currTLIValidUntil));
 	}
diff --git a/src/backend/backup/backup_manifest.c b/src/backend/backup/backup_manifest.c
index 22e2be37c95c3..d05252f383c80 100644
--- a/src/backend/backup/backup_manifest.c
+++ b/src/backend/backup/backup_manifest.c
@@ -281,7 +281,7 @@ AddWALInfoToBackupManifest(backup_manifest_info *manifest, XLogRecPtr startptr,
 		}
 
 		AppendToManifest(manifest,
-						 "%s{ \"Timeline\": %u, \"Start-LSN\": \"%X/%X\", \"End-LSN\": \"%X/%X\" }",
+						 "%s{ \"Timeline\": %u, \"Start-LSN\": \"%X/%08X\", \"End-LSN\": \"%X/%08X\" }",
 						 first_wal_range ? "" : ",\n",
 						 entry->tli,
 						 LSN_FORMAT_ARGS(tl_beginptr),
diff --git a/src/backend/backup/basebackup.c b/src/backend/backup/basebackup.c
index f0f88838dc21a..bb7d90aa5d963 100644
--- a/src/backend/backup/basebackup.c
+++ b/src/backend/backup/basebackup.c
@@ -1048,7 +1048,7 @@ SendBaseBackup(BaseBackupCmd *cmd, IncrementalBackupInfo *ib)
 		sink = bbsink_zstd_new(sink, &opt.compression_specification);
 
 	/* Set up progress reporting. */
-	sink = bbsink_progress_new(sink, opt.progress);
+	sink = bbsink_progress_new(sink, opt.progress, opt.incremental);
 
 	/*
 	 * Perform the base backup, but make sure we clean up the bbsink even if
diff --git a/src/backend/backup/basebackup_copy.c b/src/backend/backup/basebackup_copy.c
index a284ce318ff7d..18b0b5a52d3f8 100644
--- a/src/backend/backup/basebackup_copy.c
+++ b/src/backend/backup/basebackup_copy.c
@@ -361,7 +361,7 @@ SendXlogRecPtrResult(XLogRecPtr ptr, TimeLineID tli)
 	tstate = begin_tup_output_tupdesc(dest, tupdesc, &TTSOpsVirtual);
 
 	/* Data row */
-	values[0] = CStringGetTextDatum(psprintf("%X/%X", LSN_FORMAT_ARGS(ptr)));
+	values[0] = CStringGetTextDatum(psprintf("%X/%08X", LSN_FORMAT_ARGS(ptr)));
 	values[1] = Int64GetDatum(tli);
 	do_tup_output(tstate, values, nulls);
 
diff --git a/src/backend/backup/basebackup_incremental.c b/src/backend/backup/basebackup_incremental.c
index 28491b1e0ab08..a0d48ff0fefa9 100644
--- a/src/backend/backup/basebackup_incremental.c
+++ b/src/backend/backup/basebackup_incremental.c
@@ -409,7 +409,7 @@ PrepareForIncrementalBackup(IncrementalBackupInfo *ib,
 			if (range->start_lsn < tlep[i]->begin)
 				ereport(ERROR,
 						(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-						 errmsg("manifest requires WAL from initial timeline %u starting at %X/%X, but that timeline begins at %X/%X",
+						 errmsg("manifest requires WAL from initial timeline %u starting at %X/%08X, but that timeline begins at %X/%08X",
 								range->tli,
 								LSN_FORMAT_ARGS(range->start_lsn),
 								LSN_FORMAT_ARGS(tlep[i]->begin))));
@@ -419,7 +419,7 @@ PrepareForIncrementalBackup(IncrementalBackupInfo *ib,
 			if (range->start_lsn != tlep[i]->begin)
 				ereport(ERROR,
 						(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-						 errmsg("manifest requires WAL from continuation timeline %u starting at %X/%X, but that timeline begins at %X/%X",
+						 errmsg("manifest requires WAL from continuation timeline %u starting at %X/%08X, but that timeline begins at %X/%08X",
 								range->tli,
 								LSN_FORMAT_ARGS(range->start_lsn),
 								LSN_FORMAT_ARGS(tlep[i]->begin))));
@@ -430,7 +430,7 @@ PrepareForIncrementalBackup(IncrementalBackupInfo *ib,
 			if (range->end_lsn > backup_state->startpoint)
 				ereport(ERROR,
 						(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-						 errmsg("manifest requires WAL from final timeline %u ending at %X/%X, but this backup starts at %X/%X",
+						 errmsg("manifest requires WAL from final timeline %u ending at %X/%08X, but this backup starts at %X/%08X",
 								range->tli,
 								LSN_FORMAT_ARGS(range->end_lsn),
 								LSN_FORMAT_ARGS(backup_state->startpoint)),
@@ -441,7 +441,7 @@ PrepareForIncrementalBackup(IncrementalBackupInfo *ib,
 			if (range->end_lsn != tlep[i]->end)
 				ereport(ERROR,
 						(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-						 errmsg("manifest requires WAL from non-final timeline %u ending at %X/%X, but this server switched timelines at %X/%X",
+						 errmsg("manifest requires WAL from non-final timeline %u ending at %X/%08X, but this server switched timelines at %X/%08X",
 								range->tli,
 								LSN_FORMAT_ARGS(range->end_lsn),
 								LSN_FORMAT_ARGS(tlep[i]->end))));
@@ -522,18 +522,18 @@ PrepareForIncrementalBackup(IncrementalBackupInfo *ib,
 			if (XLogRecPtrIsInvalid(tli_missing_lsn))
 				ereport(ERROR,
 						(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-						 errmsg("WAL summaries are required on timeline %u from %X/%X to %X/%X, but no summaries for that timeline and LSN range exist",
+						 errmsg("WAL summaries are required on timeline %u from %X/%08X to %X/%08X, but no summaries for that timeline and LSN range exist",
 								tle->tli,
 								LSN_FORMAT_ARGS(tli_start_lsn),
 								LSN_FORMAT_ARGS(tli_end_lsn))));
 			else
 				ereport(ERROR,
 						(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-						 errmsg("WAL summaries are required on timeline %u from %X/%X to %X/%X, but the summaries for that timeline and LSN range are incomplete",
+						 errmsg("WAL summaries are required on timeline %u from %X/%08X to %X/%08X, but the summaries for that timeline and LSN range are incomplete",
 								tle->tli,
 								LSN_FORMAT_ARGS(tli_start_lsn),
 								LSN_FORMAT_ARGS(tli_end_lsn)),
-						 errdetail("The first unsummarized LSN in this range is %X/%X.",
+						 errdetail("The first unsummarized LSN in this range is %X/%08X.",
 								   LSN_FORMAT_ARGS(tli_missing_lsn))));
 		}
 
diff --git a/src/backend/backup/basebackup_progress.c b/src/backend/backup/basebackup_progress.c
index 1d22b541f89af..dac205936229b 100644
--- a/src/backend/backup/basebackup_progress.c
+++ b/src/backend/backup/basebackup_progress.c
@@ -56,7 +56,7 @@ static const bbsink_ops bbsink_progress_ops = {
  * forwards data to a successor sink.
  */
 bbsink *
-bbsink_progress_new(bbsink *next, bool estimate_backup_size)
+bbsink_progress_new(bbsink *next, bool estimate_backup_size, bool incremental)
 {
 	bbsink	   *sink;
 
@@ -69,10 +69,15 @@ bbsink_progress_new(bbsink *next, bool estimate_backup_size)
 	/*
 	 * Report that a base backup is in progress, and set the total size of the
 	 * backup to -1, which will get translated to NULL. If we're estimating
-	 * the backup size, we'll insert the real estimate when we have it.
+	 * the backup size, we'll insert the real estimate when we have it. Also,
+	 * the backup type is set.
 	 */
 	pgstat_progress_start_command(PROGRESS_COMMAND_BASEBACKUP, InvalidOid);
 	pgstat_progress_update_param(PROGRESS_BASEBACKUP_BACKUP_TOTAL, -1);
+	pgstat_progress_update_param(PROGRESS_BASEBACKUP_BACKUP_TYPE,
+								 incremental
+								 ? PROGRESS_BASEBACKUP_BACKUP_TYPE_INCREMENTAL
+								 : PROGRESS_BASEBACKUP_BACKUP_TYPE_FULL);
 
 	return sink;
 }
diff --git a/src/backend/bootstrap/bootstrap.c b/src/backend/bootstrap/bootstrap.c
index 6db864892d0dd..fc8638c1b61b6 100644
--- a/src/backend/bootstrap/bootstrap.c
+++ b/src/backend/bootstrap/bootstrap.c
@@ -109,6 +109,8 @@ static const struct typinfo TypInfo[] = {
 	F_REGROLEIN, F_REGROLEOUT},
 	{"regnamespace", REGNAMESPACEOID, 0, 4, true, TYPALIGN_INT, TYPSTORAGE_PLAIN, InvalidOid,
 	F_REGNAMESPACEIN, F_REGNAMESPACEOUT},
+	{"regdatabase", REGDATABASEOID, 0, 4, true, TYPALIGN_INT, TYPSTORAGE_PLAIN, InvalidOid,
+	F_REGDATABASEIN, F_REGDATABASEOUT},
 	{"text", TEXTOID, 0, -1, false, TYPALIGN_INT, TYPSTORAGE_EXTENDED, DEFAULT_COLLATION_OID,
 	F_TEXTIN, F_TEXTOUT},
 	{"oid", OIDOID, 0, 4, true, TYPALIGN_INT, TYPSTORAGE_PLAIN, InvalidOid,
diff --git a/src/backend/catalog/dependency.c b/src/backend/catalog/dependency.c
index 18316a3968bcf..7dded634eb810 100644
--- a/src/backend/catalog/dependency.c
+++ b/src/backend/catalog/dependency.c
@@ -1850,6 +1850,17 @@ find_expr_references_walker(Node *node,
 							 errmsg("constant of the type %s cannot be used here",
 									"regrole")));
 					break;
+
+					/*
+					 * Dependencies for regdatabase should be shared among all
+					 * databases, so explicitly inhibit to have dependencies.
+					 */
+				case REGDATABASEOID:
+					ereport(ERROR,
+							(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+							 errmsg("constant of the type %s cannot be used here",
+									"regdatabase")));
+					break;
 			}
 		}
 		return false;
diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c
index aa216683b74fe..c4029a4f3d310 100644
--- a/src/backend/catalog/index.c
+++ b/src/backend/catalog/index.c
@@ -800,11 +800,11 @@ index_create(Relation heapRelation,
 				 errmsg("user-defined indexes on system catalog tables are not supported")));
 
 	/*
-	 * Btree text_pattern_ops uses text_eq as the equality operator, which is
-	 * fine as long as the collation is deterministic; text_eq then reduces to
+	 * Btree text_pattern_ops uses texteq as the equality operator, which is
+	 * fine as long as the collation is deterministic; texteq then reduces to
 	 * bitwise equality and so it is semantically compatible with the other
 	 * operators and functions in that opclass.  But with a nondeterministic
-	 * collation, text_eq could yield results that are incompatible with the
+	 * collation, texteq could yield results that are incompatible with the
 	 * actual behavior of the index (which is determined by the opclass's
 	 * comparison function).  We prevent such problems by refusing creation of
 	 * an index with that opclass and a nondeterministic collation.
@@ -814,7 +814,7 @@ index_create(Relation heapRelation,
 	 * opclasses as incompatible with nondeterminism; but for now, this small
 	 * hack suffices.
 	 *
-	 * Another solution is to use a special operator, not text_eq, as the
+	 * Another solution is to use a special operator, not texteq, as the
 	 * equality opclass member; but that is undesirable because it would
 	 * prevent index usage in many queries that work fine today.
 	 */
diff --git a/src/backend/catalog/pg_subscription.c b/src/backend/catalog/pg_subscription.c
index 1395032413e3d..244acf52f3602 100644
--- a/src/backend/catalog/pg_subscription.c
+++ b/src/backend/catalog/pg_subscription.c
@@ -103,6 +103,7 @@ GetSubscription(Oid subid, bool missing_ok)
 	sub->passwordrequired = subform->subpasswordrequired;
 	sub->runasowner = subform->subrunasowner;
 	sub->failover = subform->subfailover;
+	sub->retaindeadtuples = subform->subretaindeadtuples;
 
 	/* Get conninfo */
 	datum = SysCacheGetAttrNotNull(SUBSCRIPTIONOID,
@@ -319,7 +320,7 @@ AddSubscriptionRelState(Oid subid, Oid relid, char state,
  */
 void
 UpdateSubscriptionRelState(Oid subid, Oid relid, char state,
-						   XLogRecPtr sublsn)
+						   XLogRecPtr sublsn, bool already_locked)
 {
 	Relation	rel;
 	HeapTuple	tup;
@@ -327,9 +328,24 @@ UpdateSubscriptionRelState(Oid subid, Oid relid, char state,
 	Datum		values[Natts_pg_subscription_rel];
 	bool		replaces[Natts_pg_subscription_rel];
 
-	LockSharedObject(SubscriptionRelationId, subid, 0, AccessShareLock);
+	if (already_locked)
+	{
+#ifdef USE_ASSERT_CHECKING
+		LOCKTAG		tag;
 
-	rel = table_open(SubscriptionRelRelationId, RowExclusiveLock);
+		Assert(CheckRelationOidLockedByMe(SubscriptionRelRelationId,
+										  RowExclusiveLock, true));
+		SET_LOCKTAG_OBJECT(tag, InvalidOid, SubscriptionRelationId, subid, 0);
+		Assert(LockHeldByMe(&tag, AccessShareLock, true));
+#endif
+
+		rel = table_open(SubscriptionRelRelationId, NoLock);
+	}
+	else
+	{
+		LockSharedObject(SubscriptionRelationId, subid, 0, AccessShareLock);
+		rel = table_open(SubscriptionRelRelationId, RowExclusiveLock);
+	}
 
 	/* Try finding existing mapping. */
 	tup = SearchSysCacheCopy2(SUBSCRIPTIONRELMAP,
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 08f780a2e6382..1b3c5a55882df 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -666,6 +666,14 @@ GRANT SELECT ON pg_shmem_allocations_numa TO pg_read_all_stats;
 REVOKE EXECUTE ON FUNCTION pg_get_shmem_allocations_numa() FROM PUBLIC;
 GRANT EXECUTE ON FUNCTION pg_get_shmem_allocations_numa() TO pg_read_all_stats;
 
+CREATE VIEW pg_dsm_registry_allocations AS
+    SELECT * FROM pg_get_dsm_registry_allocations();
+
+REVOKE ALL ON pg_dsm_registry_allocations FROM PUBLIC;
+GRANT SELECT ON pg_dsm_registry_allocations TO pg_read_all_stats;
+REVOKE EXECUTE ON FUNCTION pg_get_dsm_registry_allocations() FROM PUBLIC;
+GRANT EXECUTE ON FUNCTION pg_get_dsm_registry_allocations() TO pg_read_all_stats;
+
 CREATE VIEW pg_backend_memory_contexts AS
     SELECT * FROM pg_get_backend_memory_contexts();
 
@@ -895,7 +903,7 @@ CREATE VIEW pg_stat_activity AS
             S.wait_event,
             S.state,
             S.backend_xid,
-            s.backend_xmin,
+            S.backend_xmin,
             S.query_id,
             S.query,
             S.backend_type
@@ -1319,7 +1327,10 @@ CREATE VIEW pg_stat_progress_basebackup AS
         CASE S.param2 WHEN -1 THEN NULL ELSE S.param2 END AS backup_total,
         S.param3 AS backup_streamed,
         S.param4 AS tablespaces_total,
-        S.param5 AS tablespaces_streamed
+        S.param5 AS tablespaces_streamed,
+        CASE S.param6 WHEN 1 THEN 'full'
+                      WHEN 2 THEN 'incremental'
+                      END AS backup_type
     FROM pg_stat_get_progress_info('BASEBACKUP') AS S;
 
 
@@ -1378,7 +1389,8 @@ REVOKE ALL ON pg_subscription FROM public;
 GRANT SELECT (oid, subdbid, subskiplsn, subname, subowner, subenabled,
               subbinary, substream, subtwophasestate, subdisableonerr,
 			  subpasswordrequired, subrunasowner, subfailover,
-              subslotname, subsynccommit, subpublications, suborigin)
+			  subretaindeadtuples, subslotname, subsynccommit,
+			  subpublications, suborigin)
     ON pg_subscription TO public;
 
 CREATE VIEW pg_stat_subscription_stats AS
@@ -1390,6 +1402,7 @@ CREATE VIEW pg_stat_subscription_stats AS
         ss.confl_insert_exists,
         ss.confl_update_origin_differs,
         ss.confl_update_exists,
+        ss.confl_update_deleted,
         ss.confl_update_missing,
         ss.confl_delete_origin_differs,
         ss.confl_delete_missing,
diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c
index 4fffb76e55735..40d66537ad730 100644
--- a/src/backend/commands/analyze.c
+++ b/src/backend/commands/analyze.c
@@ -76,7 +76,7 @@ static BufferAccessStrategy vac_strategy;
 
 
 static void do_analyze_rel(Relation onerel,
-						   VacuumParams *params, List *va_cols,
+						   const VacuumParams params, List *va_cols,
 						   AcquireSampleRowsFunc acquirefunc, BlockNumber relpages,
 						   bool inh, bool in_outer_xact, int elevel);
 static void compute_index_stats(Relation onerel, double totalrows,
@@ -107,7 +107,7 @@ static Datum ind_fetch_func(VacAttrStatsP stats, int rownum, bool *isNull);
  */
 void
 analyze_rel(Oid relid, RangeVar *relation,
-			VacuumParams *params, List *va_cols, bool in_outer_xact,
+			const VacuumParams params, List *va_cols, bool in_outer_xact,
 			BufferAccessStrategy bstrategy)
 {
 	Relation	onerel;
@@ -116,7 +116,7 @@ analyze_rel(Oid relid, RangeVar *relation,
 	BlockNumber relpages = 0;
 
 	/* Select logging level */
-	if (params->options & VACOPT_VERBOSE)
+	if (params.options & VACOPT_VERBOSE)
 		elevel = INFO;
 	else
 		elevel = DEBUG2;
@@ -138,8 +138,8 @@ analyze_rel(Oid relid, RangeVar *relation,
 	 *
 	 * Make sure to generate only logs for ANALYZE in this case.
 	 */
-	onerel = vacuum_open_relation(relid, relation, params->options & ~(VACOPT_VACUUM),
-								  params->log_min_duration >= 0,
+	onerel = vacuum_open_relation(relid, relation, params.options & ~(VACOPT_VACUUM),
+								  params.log_min_duration >= 0,
 								  ShareUpdateExclusiveLock);
 
 	/* leave if relation could not be opened or locked */
@@ -155,7 +155,7 @@ analyze_rel(Oid relid, RangeVar *relation,
 	 */
 	if (!vacuum_is_permitted_for_relation(RelationGetRelid(onerel),
 										  onerel->rd_rel,
-										  params->options & ~VACOPT_VACUUM))
+										  params.options & ~VACOPT_VACUUM))
 	{
 		relation_close(onerel, ShareUpdateExclusiveLock);
 		return;
@@ -227,7 +227,7 @@ analyze_rel(Oid relid, RangeVar *relation,
 	else
 	{
 		/* No need for a WARNING if we already complained during VACUUM */
-		if (!(params->options & VACOPT_VACUUM))
+		if (!(params.options & VACOPT_VACUUM))
 			ereport(WARNING,
 					(errmsg("skipping \"%s\" --- cannot analyze non-tables or special system tables",
 							RelationGetRelationName(onerel))));
@@ -275,7 +275,7 @@ analyze_rel(Oid relid, RangeVar *relation,
  * appropriate acquirefunc for each child table.
  */
 static void
-do_analyze_rel(Relation onerel, VacuumParams *params,
+do_analyze_rel(Relation onerel, const VacuumParams params,
 			   List *va_cols, AcquireSampleRowsFunc acquirefunc,
 			   BlockNumber relpages, bool inh, bool in_outer_xact,
 			   int elevel)
@@ -309,9 +309,9 @@ do_analyze_rel(Relation onerel, VacuumParams *params,
 	PgStat_Counter startreadtime = 0;
 	PgStat_Counter startwritetime = 0;
 
-	verbose = (params->options & VACOPT_VERBOSE) != 0;
+	verbose = (params.options & VACOPT_VERBOSE) != 0;
 	instrument = (verbose || (AmAutoVacuumWorkerProcess() &&
-							  params->log_min_duration >= 0));
+							  params.log_min_duration >= 0));
 	if (inh)
 		ereport(elevel,
 				(errmsg("analyzing \"%s.%s\" inheritance tree",
@@ -690,8 +690,8 @@ do_analyze_rel(Relation onerel, VacuumParams *params,
 	 * only do it for inherited stats. (We're never called for not-inherited
 	 * stats on partitioned tables anyway.)
 	 *
-	 * Reset the changes_since_analyze counter only if we analyzed all
-	 * columns; otherwise, there is still work for auto-analyze to do.
+	 * Reset the mod_since_analyze counter only if we analyzed all columns;
+	 * otherwise, there is still work for auto-analyze to do.
 	 */
 	if (!inh)
 		pgstat_report_analyze(onerel, totalrows, totaldeadrows,
@@ -706,7 +706,7 @@ do_analyze_rel(Relation onerel, VacuumParams *params,
 	 * amvacuumcleanup() when called in ANALYZE-only mode.  The only exception
 	 * among core index AMs is GIN/ginvacuumcleanup().
 	 */
-	if (!(params->options & VACOPT_VACUUM))
+	if (!(params.options & VACOPT_VACUUM))
 	{
 		for (ind = 0; ind < nindexes; ind++)
 		{
@@ -736,9 +736,9 @@ do_analyze_rel(Relation onerel, VacuumParams *params,
 	{
 		TimestampTz endtime = GetCurrentTimestamp();
 
-		if (verbose || params->log_min_duration == 0 ||
+		if (verbose || params.log_min_duration == 0 ||
 			TimestampDifferenceExceeds(starttime, endtime,
-									   params->log_min_duration))
+									   params.log_min_duration))
 		{
 			long		delay_in_ms;
 			WalUsage	walusage;
diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c
index 54a08e4102e14..b55221d44cd00 100644
--- a/src/backend/commands/cluster.c
+++ b/src/backend/commands/cluster.c
@@ -917,7 +917,7 @@ copy_table_data(Relation NewHeap, Relation OldHeap, Relation OldIndex, bool verb
 	 * not to be aggressive about this.
 	 */
 	memset(&params, 0, sizeof(VacuumParams));
-	vacuum_get_cutoffs(OldHeap, &params, &cutoffs);
+	vacuum_get_cutoffs(OldHeap, params, &cutoffs);
 
 	/*
 	 * FreezeXid will become the table's new relfrozenxid, and that mustn't go
diff --git a/src/backend/commands/copy.c b/src/backend/commands/copy.c
index 74ae42b19a710..fae9c41db6565 100644
--- a/src/backend/commands/copy.c
+++ b/src/backend/commands/copy.c
@@ -322,11 +322,13 @@ DoCopy(ParseState *pstate, const CopyStmt *stmt,
 }
 
 /*
- * Extract a CopyHeaderChoice value from a DefElem.  This is like
- * defGetBoolean() but also accepts the special value "match".
+ * Extract the CopyFormatOptions.header_line value from a DefElem.
+ *
+ * Parses the HEADER option for COPY, which can be a boolean, a non-negative
+ * integer (number of lines to skip), or the special value "match".
  */
-static CopyHeaderChoice
-defGetCopyHeaderChoice(DefElem *def, bool is_from)
+static int
+defGetCopyHeaderOption(DefElem *def, bool is_from)
 {
 	/*
 	 * If no parameter value given, assume "true" is meant.
@@ -335,20 +337,27 @@ defGetCopyHeaderChoice(DefElem *def, bool is_from)
 		return COPY_HEADER_TRUE;
 
 	/*
-	 * Allow 0, 1, "true", "false", "on", "off", or "match".
+	 * Allow 0, 1, "true", "false", "on", "off", a non-negative integer, or
+	 * "match".
 	 */
 	switch (nodeTag(def->arg))
 	{
 		case T_Integer:
-			switch (intVal(def->arg))
 			{
-				case 0:
-					return COPY_HEADER_FALSE;
-				case 1:
-					return COPY_HEADER_TRUE;
-				default:
-					/* otherwise, error out below */
-					break;
+				int			ival = intVal(def->arg);
+
+				if (ival < 0)
+					ereport(ERROR,
+							(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+							 errmsg("a negative integer value cannot be "
+									"specified for %s", def->defname)));
+
+				if (!is_from && ival > 1)
+					ereport(ERROR,
+							(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+							 errmsg("cannot use multi-line header in COPY TO")));
+
+				return ival;
 			}
 			break;
 		default:
@@ -381,7 +390,8 @@ defGetCopyHeaderChoice(DefElem *def, bool is_from)
 	}
 	ereport(ERROR,
 			(errcode(ERRCODE_SYNTAX_ERROR),
-			 errmsg("%s requires a Boolean value or \"match\"",
+			 errmsg("%s requires a Boolean value, a non-negative integer, "
+					"or the string \"match\"",
 					def->defname)));
 	return COPY_HEADER_FALSE;	/* keep compiler quiet */
 }
@@ -566,7 +576,7 @@ ProcessCopyOptions(ParseState *pstate,
 			if (header_specified)
 				errorConflictingDefElem(defel, pstate);
 			header_specified = true;
-			opts_out->header_line = defGetCopyHeaderChoice(defel, is_from);
+			opts_out->header_line = defGetCopyHeaderOption(defel, is_from);
 		}
 		else if (strcmp(defel->defname, "quote") == 0)
 		{
@@ -769,7 +779,7 @@ ProcessCopyOptions(ParseState *pstate,
 				 errmsg("COPY delimiter cannot be \"%s\"", opts_out->delim)));
 
 	/* Check header */
-	if (opts_out->binary && opts_out->header_line)
+	if (opts_out->binary && opts_out->header_line != COPY_HEADER_FALSE)
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 		/*- translator: %s is the name of a COPY option, e.g. ON_ERROR */
diff --git a/src/backend/commands/copyfromparse.c b/src/backend/commands/copyfromparse.c
index f5fc346e2013b..b1ae97b833dff 100644
--- a/src/backend/commands/copyfromparse.c
+++ b/src/backend/commands/copyfromparse.c
@@ -771,21 +771,30 @@ static pg_attribute_always_inline bool
 NextCopyFromRawFieldsInternal(CopyFromState cstate, char ***fields, int *nfields, bool is_csv)
 {
 	int			fldct;
-	bool		done;
+	bool		done = false;
 
 	/* only available for text or csv input */
 	Assert(!cstate->opts.binary);
 
 	/* on input check that the header line is correct if needed */
-	if (cstate->cur_lineno == 0 && cstate->opts.header_line)
+	if (cstate->cur_lineno == 0 && cstate->opts.header_line != COPY_HEADER_FALSE)
 	{
 		ListCell   *cur;
 		TupleDesc	tupDesc;
+		int			lines_to_skip = cstate->opts.header_line;
+
+		/* If set to "match", one header line is skipped */
+		if (cstate->opts.header_line == COPY_HEADER_MATCH)
+			lines_to_skip = 1;
 
 		tupDesc = RelationGetDescr(cstate->rel);
 
-		cstate->cur_lineno++;
-		done = CopyReadLine(cstate, is_csv);
+		for (int i = 0; i < lines_to_skip; i++)
+		{
+			cstate->cur_lineno++;
+			if ((done = CopyReadLine(cstate, is_csv)))
+				break;
+		}
 
 		if (cstate->opts.header_line == COPY_HEADER_MATCH)
 		{
@@ -1538,7 +1547,7 @@ GetDecimalFromHex(char hex)
 	if (isdigit((unsigned char) hex))
 		return hex - '0';
 	else
-		return tolower((unsigned char) hex) - 'a' + 10;
+		return pg_ascii_tolower((unsigned char) hex) - 'a' + 10;
 }
 
 /*
diff --git a/src/backend/commands/copyto.c b/src/backend/commands/copyto.c
index ea6f18f2c8008..67b94b91cae44 100644
--- a/src/backend/commands/copyto.c
+++ b/src/backend/commands/copyto.c
@@ -199,7 +199,7 @@ CopyToTextLikeStart(CopyToState cstate, TupleDesc tupDesc)
 														  cstate->file_encoding);
 
 	/* if a header has been requested send the line */
-	if (cstate->opts.header_line)
+	if (cstate->opts.header_line == COPY_HEADER_TRUE)
 	{
 		ListCell   *cur;
 		bool		hdr_delim = false;
diff --git a/src/backend/commands/dbcommands.c b/src/backend/commands/dbcommands.c
index c95eb94501671..92a396b8406a3 100644
--- a/src/backend/commands/dbcommands.c
+++ b/src/backend/commands/dbcommands.c
@@ -570,8 +570,8 @@ CreateDatabaseUsingFileCopy(Oid src_dboid, Oid dst_dboid, Oid src_tsid,
 	 * any CREATE DATABASE commands.
 	 */
 	if (!IsBinaryUpgrade)
-		RequestCheckpoint(CHECKPOINT_IMMEDIATE | CHECKPOINT_FORCE |
-						  CHECKPOINT_WAIT | CHECKPOINT_FLUSH_ALL);
+		RequestCheckpoint(CHECKPOINT_FAST | CHECKPOINT_FORCE |
+						  CHECKPOINT_WAIT | CHECKPOINT_FLUSH_UNLOGGED);
 
 	/*
 	 * Iterate through all tablespaces of the template database, and copy each
@@ -673,7 +673,7 @@ CreateDatabaseUsingFileCopy(Oid src_dboid, Oid dst_dboid, Oid src_tsid,
 	 * strategy that avoids these problems.
 	 */
 	if (!IsBinaryUpgrade)
-		RequestCheckpoint(CHECKPOINT_IMMEDIATE | CHECKPOINT_FORCE |
+		RequestCheckpoint(CHECKPOINT_FAST | CHECKPOINT_FORCE |
 						  CHECKPOINT_WAIT);
 }
 
@@ -1052,7 +1052,7 @@ createdb(ParseState *pstate, const CreatedbStmt *stmt)
 		dbctype = src_ctype;
 	if (dblocprovider == '\0')
 		dblocprovider = src_locprovider;
-	if (dblocale == NULL)
+	if (dblocale == NULL && dblocprovider == src_locprovider)
 		dblocale = src_locale;
 	if (dbicurules == NULL)
 		dbicurules = src_icurules;
@@ -1870,7 +1870,7 @@ dropdb(const char *dbname, bool missing_ok, bool force)
 	 * Force a checkpoint to make sure the checkpointer has received the
 	 * message sent by ForgetDatabaseSyncRequests.
 	 */
-	RequestCheckpoint(CHECKPOINT_IMMEDIATE | CHECKPOINT_FORCE | CHECKPOINT_WAIT);
+	RequestCheckpoint(CHECKPOINT_FAST | CHECKPOINT_FORCE | CHECKPOINT_WAIT);
 
 	/* Close all smgr fds in all backends. */
 	WaitForProcSignalBarrier(EmitProcSignalBarrier(PROCSIGNAL_BARRIER_SMGRRELEASE));
@@ -2120,8 +2120,8 @@ movedb(const char *dbname, const char *tblspcname)
 	 * On Windows, this also ensures that background procs don't hold any open
 	 * files, which would cause rmdir() to fail.
 	 */
-	RequestCheckpoint(CHECKPOINT_IMMEDIATE | CHECKPOINT_FORCE | CHECKPOINT_WAIT
-					  | CHECKPOINT_FLUSH_ALL);
+	RequestCheckpoint(CHECKPOINT_FAST | CHECKPOINT_FORCE | CHECKPOINT_WAIT
+					  | CHECKPOINT_FLUSH_UNLOGGED);
 
 	/* Close all smgr fds in all backends. */
 	WaitForProcSignalBarrier(EmitProcSignalBarrier(PROCSIGNAL_BARRIER_SMGRRELEASE));
@@ -2252,7 +2252,7 @@ movedb(const char *dbname, const char *tblspcname)
 		 * any unlogged operations done in the new DB tablespace before the
 		 * next checkpoint.
 		 */
-		RequestCheckpoint(CHECKPOINT_IMMEDIATE | CHECKPOINT_FORCE | CHECKPOINT_WAIT);
+		RequestCheckpoint(CHECKPOINT_FAST | CHECKPOINT_FORCE | CHECKPOINT_WAIT);
 
 		/*
 		 * Force synchronous commit, thus minimizing the window between
diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c
index 7e2792ead715b..8345bc0264b23 100644
--- a/src/backend/commands/explain.c
+++ b/src/backend/commands/explain.c
@@ -3582,6 +3582,7 @@ static void
 show_memoize_info(MemoizeState *mstate, List *ancestors, ExplainState *es)
 {
 	Plan	   *plan = ((PlanState *) mstate)->plan;
+	Memoize    *mplan = (Memoize *) plan;
 	ListCell   *lc;
 	List	   *context;
 	StringInfoData keystr;
@@ -3602,7 +3603,7 @@ show_memoize_info(MemoizeState *mstate, List *ancestors, ExplainState *es)
 									   plan,
 									   ancestors);
 
-	foreach(lc, ((Memoize *) plan)->param_exprs)
+	foreach(lc, mplan->param_exprs)
 	{
 		Node	   *expr = (Node *) lfirst(lc);
 
@@ -3618,6 +3619,24 @@ show_memoize_info(MemoizeState *mstate, List *ancestors, ExplainState *es)
 
 	pfree(keystr.data);
 
+	if (es->costs)
+	{
+		if (es->format == EXPLAIN_FORMAT_TEXT)
+		{
+			ExplainIndentText(es);
+			appendStringInfo(es->str, "Estimates: capacity=%u distinct keys=%.0f lookups=%.0f hit percent=%.2f%%\n",
+							 mplan->est_entries, mplan->est_unique_keys,
+							 mplan->est_calls, mplan->est_hit_ratio * 100.0);
+		}
+		else
+		{
+			ExplainPropertyUInteger("Estimated Capacity", NULL, mplan->est_entries, es);
+			ExplainPropertyFloat("Estimated Distinct Lookup Keys", NULL, mplan->est_unique_keys, 0, es);
+			ExplainPropertyFloat("Estimated Lookups", NULL, mplan->est_calls, 0, es);
+			ExplainPropertyFloat("Estimated Hit Percent", NULL, mplan->est_hit_ratio * 100.0, 2, es);
+		}
+	}
+
 	if (!es->analyze)
 		return;
 
diff --git a/src/backend/commands/foreigncmds.c b/src/backend/commands/foreigncmds.c
index 8d2d743154462..77f8461f42eee 100644
--- a/src/backend/commands/foreigncmds.c
+++ b/src/backend/commands/foreigncmds.c
@@ -1588,6 +1588,7 @@ ImportForeignSchema(ImportForeignSchemaStmt *stmt)
 			pstmt->utilityStmt = (Node *) cstmt;
 			pstmt->stmt_location = rs->stmt_location;
 			pstmt->stmt_len = rs->stmt_len;
+			pstmt->planOrigin = PLAN_STMT_INTERNAL;
 
 			/* Execute statement */
 			ProcessUtility(pstmt, cmd, false,
diff --git a/src/backend/commands/publicationcmds.c b/src/backend/commands/publicationcmds.c
index 1bf7eaae5b362..803c26ab216dd 100644
--- a/src/backend/commands/publicationcmds.c
+++ b/src/backend/commands/publicationcmds.c
@@ -2113,20 +2113,20 @@ AlterPublicationOwner_oid(Oid pubid, Oid newOwnerId)
 static char
 defGetGeneratedColsOption(DefElem *def)
 {
-	char	   *sval;
+	char	   *sval = "";
 
 	/*
-	 * If no parameter value given, assume "stored" is meant.
+	 * A parameter value is required.
 	 */
-	if (!def->arg)
-		return PUBLISH_GENCOLS_STORED;
-
-	sval = defGetString(def);
+	if (def->arg)
+	{
+		sval = defGetString(def);
 
-	if (pg_strcasecmp(sval, "none") == 0)
-		return PUBLISH_GENCOLS_NONE;
-	if (pg_strcasecmp(sval, "stored") == 0)
-		return PUBLISH_GENCOLS_STORED;
+		if (pg_strcasecmp(sval, "none") == 0)
+			return PUBLISH_GENCOLS_NONE;
+		if (pg_strcasecmp(sval, "stored") == 0)
+			return PUBLISH_GENCOLS_STORED;
+	}
 
 	ereport(ERROR,
 			errcode(ERRCODE_SYNTAX_ERROR),
diff --git a/src/backend/commands/schemacmds.c b/src/backend/commands/schemacmds.c
index 546160f09410e..0f03d9743d203 100644
--- a/src/backend/commands/schemacmds.c
+++ b/src/backend/commands/schemacmds.c
@@ -215,6 +215,7 @@ CreateSchemaCommand(CreateSchemaStmt *stmt, const char *queryString,
 		wrapper->utilityStmt = stmt;
 		wrapper->stmt_location = stmt_location;
 		wrapper->stmt_len = stmt_len;
+		wrapper->planOrigin = PLAN_STMT_INTERNAL;
 
 		/* do this step */
 		ProcessUtility(wrapper,
diff --git a/src/backend/commands/subscriptioncmds.c b/src/backend/commands/subscriptioncmds.c
index 4ff246cd94321..cd6c3684482f9 100644
--- a/src/backend/commands/subscriptioncmds.c
+++ b/src/backend/commands/subscriptioncmds.c
@@ -14,6 +14,7 @@
 
 #include "postgres.h"
 
+#include "access/commit_ts.h"
 #include "access/htup_details.h"
 #include "access/table.h"
 #include "access/twophase.h"
@@ -71,8 +72,9 @@
 #define SUBOPT_PASSWORD_REQUIRED	0x00000800
 #define SUBOPT_RUN_AS_OWNER			0x00001000
 #define SUBOPT_FAILOVER				0x00002000
-#define SUBOPT_LSN					0x00004000
-#define SUBOPT_ORIGIN				0x00008000
+#define SUBOPT_RETAIN_DEAD_TUPLES	0x00004000
+#define SUBOPT_LSN					0x00008000
+#define SUBOPT_ORIGIN				0x00010000
 
 /* check if the 'val' has 'bits' set */
 #define IsSet(val, bits)  (((val) & (bits)) == (bits))
@@ -98,6 +100,7 @@ typedef struct SubOpts
 	bool		passwordrequired;
 	bool		runasowner;
 	bool		failover;
+	bool		retaindeadtuples;
 	char	   *origin;
 	XLogRecPtr	lsn;
 } SubOpts;
@@ -105,8 +108,10 @@ typedef struct SubOpts
 static List *fetch_table_list(WalReceiverConn *wrconn, List *publications);
 static void check_publications_origin(WalReceiverConn *wrconn,
 									  List *publications, bool copydata,
-									  char *origin, Oid *subrel_local_oids,
-									  int subrel_count, char *subname);
+									  bool retain_dead_tuples, char *origin,
+									  Oid *subrel_local_oids, int subrel_count,
+									  char *subname);
+static void check_pub_dead_tuple_retention(WalReceiverConn *wrconn);
 static void check_duplicates_in_publist(List *publist, Datum *datums);
 static List *merge_publications(List *oldpublist, List *newpublist, bool addpub, const char *subname);
 static void ReportSlotConnectionError(List *rstates, Oid subid, char *slotname, char *err);
@@ -162,6 +167,8 @@ parse_subscription_options(ParseState *pstate, List *stmt_options,
 		opts->runasowner = false;
 	if (IsSet(supported_opts, SUBOPT_FAILOVER))
 		opts->failover = false;
+	if (IsSet(supported_opts, SUBOPT_RETAIN_DEAD_TUPLES))
+		opts->retaindeadtuples = false;
 	if (IsSet(supported_opts, SUBOPT_ORIGIN))
 		opts->origin = pstrdup(LOGICALREP_ORIGIN_ANY);
 
@@ -210,7 +217,7 @@ parse_subscription_options(ParseState *pstate, List *stmt_options,
 			if (strcmp(opts->slot_name, "none") == 0)
 				opts->slot_name = NULL;
 			else
-				ReplicationSlotValidateName(opts->slot_name, ERROR);
+				ReplicationSlotValidateName(opts->slot_name, false, ERROR);
 		}
 		else if (IsSet(supported_opts, SUBOPT_COPY_DATA) &&
 				 strcmp(defel->defname, "copy_data") == 0)
@@ -307,6 +314,15 @@ parse_subscription_options(ParseState *pstate, List *stmt_options,
 			opts->specified_opts |= SUBOPT_FAILOVER;
 			opts->failover = defGetBoolean(defel);
 		}
+		else if (IsSet(supported_opts, SUBOPT_RETAIN_DEAD_TUPLES) &&
+				 strcmp(defel->defname, "retain_dead_tuples") == 0)
+		{
+			if (IsSet(opts->specified_opts, SUBOPT_RETAIN_DEAD_TUPLES))
+				errorConflictingDefElem(defel, pstate);
+
+			opts->specified_opts |= SUBOPT_RETAIN_DEAD_TUPLES;
+			opts->retaindeadtuples = defGetBoolean(defel);
+		}
 		else if (IsSet(supported_opts, SUBOPT_ORIGIN) &&
 				 strcmp(defel->defname, "origin") == 0)
 		{
@@ -563,7 +579,8 @@ CreateSubscription(ParseState *pstate, CreateSubscriptionStmt *stmt,
 					  SUBOPT_SYNCHRONOUS_COMMIT | SUBOPT_BINARY |
 					  SUBOPT_STREAMING | SUBOPT_TWOPHASE_COMMIT |
 					  SUBOPT_DISABLE_ON_ERR | SUBOPT_PASSWORD_REQUIRED |
-					  SUBOPT_RUN_AS_OWNER | SUBOPT_FAILOVER | SUBOPT_ORIGIN);
+					  SUBOPT_RUN_AS_OWNER | SUBOPT_FAILOVER |
+					  SUBOPT_RETAIN_DEAD_TUPLES | SUBOPT_ORIGIN);
 	parse_subscription_options(pstate, stmt->options, supported_opts, &opts);
 
 	/*
@@ -630,6 +647,10 @@ CreateSubscription(ParseState *pstate, CreateSubscriptionStmt *stmt,
 						stmt->subname)));
 	}
 
+	/* Ensure that we can enable retain_dead_tuples */
+	if (opts.retaindeadtuples)
+		CheckSubDeadTupleRetention(true, !opts.enabled, WARNING);
+
 	if (!IsSet(opts.specified_opts, SUBOPT_SLOT_NAME) &&
 		opts.slot_name == NULL)
 		opts.slot_name = stmt->subname;
@@ -670,6 +691,8 @@ CreateSubscription(ParseState *pstate, CreateSubscriptionStmt *stmt,
 	values[Anum_pg_subscription_subpasswordrequired - 1] = BoolGetDatum(opts.passwordrequired);
 	values[Anum_pg_subscription_subrunasowner - 1] = BoolGetDatum(opts.runasowner);
 	values[Anum_pg_subscription_subfailover - 1] = BoolGetDatum(opts.failover);
+	values[Anum_pg_subscription_subretaindeadtuples - 1] =
+		BoolGetDatum(opts.retaindeadtuples);
 	values[Anum_pg_subscription_subconninfo - 1] =
 		CStringGetTextDatum(conninfo);
 	if (opts.slot_name)
@@ -722,7 +745,11 @@ CreateSubscription(ParseState *pstate, CreateSubscriptionStmt *stmt,
 		{
 			check_publications(wrconn, publications);
 			check_publications_origin(wrconn, publications, opts.copy_data,
-									  opts.origin, NULL, 0, stmt->subname);
+									  opts.retaindeadtuples, opts.origin,
+									  NULL, 0, stmt->subname);
+
+			if (opts.retaindeadtuples)
+				check_pub_dead_tuple_retention(wrconn);
 
 			/*
 			 * Set sync state based on if we were asked to do data copy or
@@ -881,8 +908,8 @@ AlterSubscription_refresh(Subscription *sub, bool copy_data,
 			  sizeof(Oid), oid_cmp);
 
 		check_publications_origin(wrconn, sub->publications, copy_data,
-								  sub->origin, subrel_local_oids,
-								  subrel_count, sub->name);
+								  sub->retaindeadtuples, sub->origin,
+								  subrel_local_oids, subrel_count, sub->name);
 
 		/*
 		 * Rels that we want to remove from subscription and drop any slots
@@ -1040,18 +1067,22 @@ AlterSubscription_refresh(Subscription *sub, bool copy_data,
 }
 
 /*
- * Common checks for altering failover and two_phase options.
+ * Common checks for altering failover, two_phase, and retain_dead_tuples
+ * options.
  */
 static void
 CheckAlterSubOption(Subscription *sub, const char *option,
 					bool slot_needs_update, bool isTopLevel)
 {
+	Assert(strcmp(option, "failover") == 0 ||
+		   strcmp(option, "two_phase") == 0 ||
+		   strcmp(option, "retain_dead_tuples") == 0);
+
 	/*
-	 * The checks in this function are required only for failover and
-	 * two_phase options.
+	 * Altering the retain_dead_tuples option does not update the slot on the
+	 * publisher.
 	 */
-	Assert(strcmp(option, "failover") == 0 ||
-		   strcmp(option, "two_phase") == 0);
+	Assert(!slot_needs_update || strcmp(option, "retain_dead_tuples") != 0);
 
 	/*
 	 * Do not allow changing the option if the subscription is enabled. This
@@ -1063,6 +1094,39 @@ CheckAlterSubOption(Subscription *sub, const char *option,
 	 * the publisher by the existing walsender, so we could have allowed that
 	 * even when the subscription is enabled. But we kept this restriction for
 	 * the sake of consistency and simplicity.
+	 *
+	 * Additionally, do not allow changing the retain_dead_tuples option when
+	 * the subscription is enabled to prevent race conditions arising from the
+	 * new option value being acknowledged asynchronously by the launcher and
+	 * apply workers.
+	 *
+	 * Without the restriction, a race condition may arise when a user
+	 * disables and immediately re-enables the retain_dead_tuples option. In
+	 * this case, the launcher might drop the slot upon noticing the disabled
+	 * action, while the apply worker may keep maintaining
+	 * oldest_nonremovable_xid without noticing the option change. During this
+	 * period, a transaction ID wraparound could falsely make this ID appear
+	 * as if it originates from the future w.r.t the transaction ID stored in
+	 * the slot maintained by launcher.
+	 *
+	 * Similarly, if the user enables retain_dead_tuples concurrently with the
+	 * launcher starting the worker, the apply worker may start calculating
+	 * oldest_nonremovable_xid before the launcher notices the enable action.
+	 * Consequently, the launcher may update slot.xmin to a newer value than
+	 * that maintained by the worker. In subsequent cycles, upon integrating
+	 * the worker's oldest_nonremovable_xid, the launcher might detect a
+	 * retreat in the calculated xmin, necessitating additional handling.
+	 *
+	 * XXX To address the above race conditions, we can define
+	 * oldest_nonremovable_xid as FullTransactionID and adds the check to
+	 * disallow retreating the conflict slot's xmin. For now, we kept the
+	 * implementation simple by disallowing change to the retain_dead_tuples,
+	 * but in the future we can change this after some more analysis.
+	 *
+	 * Note that we could restrict only the enabling of retain_dead_tuples to
+	 * avoid the race conditions described above, but we maintain the
+	 * restriction for both enable and disable operations for the sake of
+	 * consistency.
 	 */
 	if (sub->enabled)
 		ereport(ERROR,
@@ -1110,6 +1174,9 @@ AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt,
 	bool		update_tuple = false;
 	bool		update_failover = false;
 	bool		update_two_phase = false;
+	bool		check_pub_rdt = false;
+	bool		retain_dead_tuples;
+	char	   *origin;
 	Subscription *sub;
 	Form_pg_subscription form;
 	bits32		supported_opts;
@@ -1137,6 +1204,9 @@ AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt,
 
 	sub = GetSubscription(subid, false);
 
+	retain_dead_tuples = sub->retaindeadtuples;
+	origin = sub->origin;
+
 	/*
 	 * Don't allow non-superuser modification of a subscription with
 	 * password_required=false.
@@ -1165,7 +1235,7 @@ AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt,
 								  SUBOPT_DISABLE_ON_ERR |
 								  SUBOPT_PASSWORD_REQUIRED |
 								  SUBOPT_RUN_AS_OWNER | SUBOPT_FAILOVER |
-								  SUBOPT_ORIGIN);
+								  SUBOPT_RETAIN_DEAD_TUPLES | SUBOPT_ORIGIN);
 
 				parse_subscription_options(pstate, stmt->options,
 										   supported_opts, &opts);
@@ -1325,11 +1395,62 @@ AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt,
 					replaces[Anum_pg_subscription_subfailover - 1] = true;
 				}
 
+				if (IsSet(opts.specified_opts, SUBOPT_RETAIN_DEAD_TUPLES))
+				{
+					values[Anum_pg_subscription_subretaindeadtuples - 1] =
+						BoolGetDatum(opts.retaindeadtuples);
+					replaces[Anum_pg_subscription_subretaindeadtuples - 1] = true;
+
+					CheckAlterSubOption(sub, "retain_dead_tuples", false, isTopLevel);
+
+					/*
+					 * Workers may continue running even after the
+					 * subscription has been disabled.
+					 *
+					 * To prevent race conditions (as described in
+					 * CheckAlterSubOption()), ensure that all worker
+					 * processes have already exited before proceeding.
+					 */
+					if (logicalrep_workers_find(subid, true, true))
+						ereport(ERROR,
+								(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+								 errmsg("cannot alter retain_dead_tuples when logical replication worker is still running"),
+								 errhint("Try again after some time.")));
+
+					/*
+					 * Remind the user that enabling subscription will prevent
+					 * the accumulation of dead tuples.
+					 */
+					if (opts.retaindeadtuples)
+						CheckSubDeadTupleRetention(true, !sub->enabled, NOTICE);
+
+					/*
+					 * Notify the launcher to manage the replication slot for
+					 * conflict detection. This ensures that replication slot
+					 * is efficiently handled (created, updated, or dropped)
+					 * in response to any configuration changes.
+					 */
+					ApplyLauncherWakeupAtCommit();
+
+					check_pub_rdt = opts.retaindeadtuples;
+					retain_dead_tuples = opts.retaindeadtuples;
+				}
+
 				if (IsSet(opts.specified_opts, SUBOPT_ORIGIN))
 				{
 					values[Anum_pg_subscription_suborigin - 1] =
 						CStringGetTextDatum(opts.origin);
 					replaces[Anum_pg_subscription_suborigin - 1] = true;
+
+					/*
+					 * Check if changes from different origins may be received
+					 * from the publisher when the origin is changed to ANY
+					 * and retain_dead_tuples is enabled.
+					 */
+					check_pub_rdt = retain_dead_tuples &&
+						pg_strcasecmp(opts.origin, LOGICALREP_ORIGIN_ANY) == 0;
+
+					origin = opts.origin;
 				}
 
 				update_tuple = true;
@@ -1347,6 +1468,15 @@ AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt,
 							(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
 							 errmsg("cannot enable subscription that does not have a slot name")));
 
+				/*
+				 * Check track_commit_timestamp only when enabling the
+				 * subscription in case it was disabled after creation. See
+				 * comments atop CheckSubDeadTupleRetention() for details.
+				 */
+				if (sub->retaindeadtuples)
+					CheckSubDeadTupleRetention(opts.enabled, !opts.enabled,
+											   WARNING);
+
 				values[Anum_pg_subscription_subenabled - 1] =
 					BoolGetDatum(opts.enabled);
 				replaces[Anum_pg_subscription_subenabled - 1] = true;
@@ -1355,6 +1485,14 @@ AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt,
 					ApplyLauncherWakeupAtCommit();
 
 				update_tuple = true;
+
+				/*
+				 * The subscription might be initially created with
+				 * connect=false and retain_dead_tuples=true, meaning the
+				 * remote server's status may not be checked. Ensure this
+				 * check is conducted now.
+				 */
+				check_pub_rdt = sub->retaindeadtuples && opts.enabled;
 				break;
 			}
 
@@ -1369,6 +1507,13 @@ AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt,
 				CStringGetTextDatum(stmt->conninfo);
 			replaces[Anum_pg_subscription_subconninfo - 1] = true;
 			update_tuple = true;
+
+			/*
+			 * Since the remote server configuration might have changed,
+			 * perform a check to ensure it permits enabling
+			 * retain_dead_tuples.
+			 */
+			check_pub_rdt = sub->retaindeadtuples;
 			break;
 
 		case ALTER_SUBSCRIPTION_SET_PUBLICATION:
@@ -1539,7 +1684,7 @@ AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt,
 					if (!XLogRecPtrIsInvalid(remote_lsn) && opts.lsn < remote_lsn)
 						ereport(ERROR,
 								(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-								 errmsg("skip WAL location (LSN %X/%X) must be greater than origin LSN %X/%X",
+								 errmsg("skip WAL location (LSN %X/%08X) must be greater than origin LSN %X/%08X",
 										LSN_FORMAT_ARGS(opts.lsn),
 										LSN_FORMAT_ARGS(remote_lsn))));
 				}
@@ -1568,14 +1713,15 @@ AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt,
 	}
 
 	/*
-	 * Try to acquire the connection necessary for altering the slot, if
-	 * needed.
+	 * Try to acquire the connection necessary either for modifying the slot
+	 * or for checking if the remote server permits enabling
+	 * retain_dead_tuples.
 	 *
 	 * This has to be at the end because otherwise if there is an error while
 	 * doing the database operations we won't be able to rollback altered
 	 * slot.
 	 */
-	if (update_failover || update_two_phase)
+	if (update_failover || update_two_phase || check_pub_rdt)
 	{
 		bool		must_use_password;
 		char	   *err;
@@ -1584,10 +1730,14 @@ AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt,
 		/* Load the library providing us libpq calls. */
 		load_file("libpqwalreceiver", false);
 
-		/* Try to connect to the publisher. */
+		/*
+		 * Try to connect to the publisher, using the new connection string if
+		 * available.
+		 */
 		must_use_password = sub->passwordrequired && !sub->ownersuperuser;
-		wrconn = walrcv_connect(sub->conninfo, true, true, must_use_password,
-								sub->name, &err);
+		wrconn = walrcv_connect(stmt->conninfo ? stmt->conninfo : sub->conninfo,
+								true, true, must_use_password, sub->name,
+								&err);
 		if (!wrconn)
 			ereport(ERROR,
 					(errcode(ERRCODE_CONNECTION_FAILURE),
@@ -1596,9 +1746,17 @@ AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt,
 
 		PG_TRY();
 		{
-			walrcv_alter_slot(wrconn, sub->slotname,
-							  update_failover ? &opts.failover : NULL,
-							  update_two_phase ? &opts.twophase : NULL);
+			if (retain_dead_tuples)
+				check_pub_dead_tuple_retention(wrconn);
+
+			check_publications_origin(wrconn, sub->publications, false,
+									  retain_dead_tuples, origin, NULL, 0,
+									  sub->name);
+
+			if (update_failover || update_two_phase)
+				walrcv_alter_slot(wrconn, sub->slotname,
+								  update_failover ? &opts.failover : NULL,
+								  update_two_phase ? &opts.twophase : NULL);
 		}
 		PG_FINALLY();
 		{
@@ -2086,20 +2244,29 @@ AlterSubscriptionOwner_oid(Oid subid, Oid newOwnerId)
  * Check and log a warning if the publisher has subscribed to the same table,
  * its partition ancestors (if it's a partition), or its partition children (if
  * it's a partitioned table), from some other publishers. This check is
- * required only if "copy_data = true" and "origin = none" for CREATE
- * SUBSCRIPTION and ALTER SUBSCRIPTION ... REFRESH statements to notify the
- * user that data having origin might have been copied.
+ * required in the following scenarios:
  *
- * This check need not be performed on the tables that are already added
- * because incremental sync for those tables will happen through WAL and the
- * origin of the data can be identified from the WAL records.
+ * 1) For CREATE SUBSCRIPTION and ALTER SUBSCRIPTION ... REFRESH statements
+ *    with "copy_data = true" and "origin = none":
+ *    - Warn the user that data with an origin might have been copied.
+ *    - This check is skipped for tables already added, as incremental sync via
+ *      WAL allows origin tracking. The list of such tables is in
+ *      subrel_local_oids.
  *
- * subrel_local_oids contains the list of relation oids that are already
- * present on the subscriber.
+ * 2) For CREATE SUBSCRIPTION and ALTER SUBSCRIPTION ... REFRESH statements
+ *    with "retain_dead_tuples = true" and "origin = any", and for ALTER
+ *    SUBSCRIPTION statements that modify retain_dead_tuples or origin, or
+ *    when the publisher's status changes (e.g., due to a connection string
+ *    update):
+ *    - Warn the user that only conflict detection info for local changes on
+ *      the publisher is retained. Data from other origins may lack sufficient
+ *      details for reliable conflict detection.
+ *    - See comments atop worker.c for more details.
  */
 static void
 check_publications_origin(WalReceiverConn *wrconn, List *publications,
-						  bool copydata, char *origin, Oid *subrel_local_oids,
+						  bool copydata, bool retain_dead_tuples,
+						  char *origin, Oid *subrel_local_oids,
 						  int subrel_count, char *subname)
 {
 	WalRcvExecResult *res;
@@ -2108,9 +2275,29 @@ check_publications_origin(WalReceiverConn *wrconn, List *publications,
 	Oid			tableRow[1] = {TEXTOID};
 	List	   *publist = NIL;
 	int			i;
+	bool		check_rdt;
+	bool		check_table_sync;
+	bool		origin_none = origin &&
+		pg_strcasecmp(origin, LOGICALREP_ORIGIN_NONE) == 0;
+
+	/*
+	 * Enable retain_dead_tuples checks only when origin is set to 'any',
+	 * since with origin='none' only local changes are replicated to the
+	 * subscriber.
+	 */
+	check_rdt = retain_dead_tuples && !origin_none;
+
+	/*
+	 * Enable table synchronization checks only when origin is 'none', to
+	 * ensure that data from other origins is not inadvertently copied.
+	 */
+	check_table_sync = copydata && origin_none;
 
-	if (!copydata || !origin ||
-		(pg_strcasecmp(origin, LOGICALREP_ORIGIN_NONE) != 0))
+	/* retain_dead_tuples and table sync checks occur separately */
+	Assert(!(check_rdt && check_table_sync));
+
+	/* Return if no checks are required */
+	if (!check_rdt && !check_table_sync)
 		return;
 
 	initStringInfo(&cmd);
@@ -2129,16 +2316,23 @@ check_publications_origin(WalReceiverConn *wrconn, List *publications,
 	/*
 	 * In case of ALTER SUBSCRIPTION ... REFRESH, subrel_local_oids contains
 	 * the list of relation oids that are already present on the subscriber.
-	 * This check should be skipped for these tables.
+	 * This check should be skipped for these tables if checking for table
+	 * sync scenario. However, when handling the retain_dead_tuples scenario,
+	 * ensure all tables are checked, as some existing tables may now include
+	 * changes from other origins due to newly created subscriptions on the
+	 * publisher.
 	 */
-	for (i = 0; i < subrel_count; i++)
+	if (check_table_sync)
 	{
-		Oid			relid = subrel_local_oids[i];
-		char	   *schemaname = get_namespace_name(get_rel_namespace(relid));
-		char	   *tablename = get_rel_name(relid);
+		for (i = 0; i < subrel_count; i++)
+		{
+			Oid			relid = subrel_local_oids[i];
+			char	   *schemaname = get_namespace_name(get_rel_namespace(relid));
+			char	   *tablename = get_rel_name(relid);
 
-		appendStringInfo(&cmd, "AND NOT (N.nspname = '%s' AND C.relname = '%s')\n",
-						 schemaname, tablename);
+			appendStringInfo(&cmd, "AND NOT (N.nspname = '%s' AND C.relname = '%s')\n",
+							 schemaname, tablename);
+		}
 	}
 
 	res = walrcv_exec(wrconn, cmd.data, 1, tableRow);
@@ -2173,22 +2367,37 @@ check_publications_origin(WalReceiverConn *wrconn, List *publications,
 	 * XXX: For simplicity, we don't check whether the table has any data or
 	 * not. If the table doesn't have any data then we don't need to
 	 * distinguish between data having origin and data not having origin so we
-	 * can avoid logging a warning in that case.
+	 * can avoid logging a warning for table sync scenario.
 	 */
 	if (publist)
 	{
 		StringInfo	pubnames = makeStringInfo();
+		StringInfo	err_msg = makeStringInfo();
+		StringInfo	err_hint = makeStringInfo();
 
 		/* Prepare the list of publication(s) for warning message. */
 		GetPublicationsStr(publist, pubnames, false);
+
+		if (check_table_sync)
+		{
+			appendStringInfo(err_msg, _("subscription \"%s\" requested copy_data with origin = NONE but might copy data that had a different origin"),
+							 subname);
+			appendStringInfoString(err_hint, _("Verify that initial data copied from the publisher tables did not come from other origins."));
+		}
+		else
+		{
+			appendStringInfo(err_msg, _("subscription \"%s\" enabled retain_dead_tuples but might not reliably detect conflicts for changes from different origins"),
+							 subname);
+			appendStringInfoString(err_hint, _("Consider using origin = NONE or disabling retain_dead_tuples."));
+		}
+
 		ereport(WARNING,
 				errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-				errmsg("subscription \"%s\" requested copy_data with origin = NONE but might copy data that had a different origin",
-					   subname),
-				errdetail_plural("The subscription being created subscribes to a publication (%s) that contains tables that are written to by other subscriptions.",
-								 "The subscription being created subscribes to publications (%s) that contain tables that are written to by other subscriptions.",
+				errmsg_internal("%s", err_msg->data),
+				errdetail_plural("The subscription subscribes to a publication (%s) that contains tables that are written to by other subscriptions.",
+								 "The subscription subscribes to publications (%s) that contain tables that are written to by other subscriptions.",
 								 list_length(publist), pubnames->data),
-				errhint("Verify that initial data copied from the publisher tables did not come from other origins."));
+				errhint_internal("%s", err_hint->data));
 	}
 
 	ExecDropSingleTupleTableSlot(slot);
@@ -2196,6 +2405,101 @@ check_publications_origin(WalReceiverConn *wrconn, List *publications,
 	walrcv_clear_result(res);
 }
 
+/*
+ * Determine whether the retain_dead_tuples can be enabled based on the
+ * publisher's status.
+ *
+ * This option is disallowed if the publisher is running a version earlier
+ * than the PG19, or if the publisher is in recovery (i.e., it is a standby
+ * server).
+ *
+ * See comments atop worker.c for a detailed explanation.
+ */
+static void
+check_pub_dead_tuple_retention(WalReceiverConn *wrconn)
+{
+	WalRcvExecResult *res;
+	Oid			RecoveryRow[1] = {BOOLOID};
+	TupleTableSlot *slot;
+	bool		isnull;
+	bool		remote_in_recovery;
+
+	if (walrcv_server_version(wrconn) < 19000)
+		ereport(ERROR,
+				errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				errmsg("cannot enable retain_dead_tuples if the publisher is running a version earlier than PostgreSQL 19"));
+
+	res = walrcv_exec(wrconn, "SELECT pg_is_in_recovery()", 1, RecoveryRow);
+
+	if (res->status != WALRCV_OK_TUPLES)
+		ereport(ERROR,
+				(errcode(ERRCODE_CONNECTION_FAILURE),
+				 errmsg("could not obtain recovery progress from the publisher: %s",
+						res->err)));
+
+	slot = MakeSingleTupleTableSlot(res->tupledesc, &TTSOpsMinimalTuple);
+	if (!tuplestore_gettupleslot(res->tuplestore, true, false, slot))
+		elog(ERROR, "failed to fetch tuple for the recovery progress");
+
+	remote_in_recovery = DatumGetBool(slot_getattr(slot, 1, &isnull));
+
+	if (remote_in_recovery)
+		ereport(ERROR,
+				errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				errmsg("cannot enable retain_dead_tuples if the publisher is in recovery."));
+
+	ExecDropSingleTupleTableSlot(slot);
+
+	walrcv_clear_result(res);
+}
+
+/*
+ * Check if the subscriber's configuration is adequate to enable the
+ * retain_dead_tuples option.
+ *
+ * Issue an ERROR if the wal_level does not support the use of replication
+ * slots when check_guc is set to true.
+ *
+ * Issue a WARNING if track_commit_timestamp is not enabled when check_guc is
+ * set to true. This is only to highlight the importance of enabling
+ * track_commit_timestamp instead of catching all the misconfigurations, as
+ * this setting can be adjusted after subscription creation. Without it, the
+ * apply worker will simply skip conflict detection.
+ *
+ * Issue a WARNING or NOTICE if the subscription is disabled. Do not raise an
+ * ERROR since users can only modify retain_dead_tuples for disabled
+ * subscriptions. And as long as the subscription is enabled promptly, it will
+ * not pose issues.
+ */
+void
+CheckSubDeadTupleRetention(bool check_guc, bool sub_disabled,
+						   int elevel_for_sub_disabled)
+{
+	Assert(elevel_for_sub_disabled == NOTICE ||
+		   elevel_for_sub_disabled == WARNING);
+
+	if (check_guc && wal_level < WAL_LEVEL_REPLICA)
+		ereport(ERROR,
+				errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				errmsg("\"wal_level\" is insufficient to create the replication slot required by retain_dead_tuples"),
+				errhint("\"wal_level\" must be set to \"replica\" or \"logical\" at server start."));
+
+	if (check_guc && !track_commit_timestamp)
+		ereport(WARNING,
+				errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				errmsg("commit timestamp and origin data required for detecting conflicts won't be retained"),
+				errhint("Consider setting \"%s\" to true.",
+						"track_commit_timestamp"));
+
+	if (sub_disabled)
+		ereport(elevel_for_sub_disabled,
+				errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				errmsg("deleted rows to detect conflicts would not be removed until the subscription is enabled"),
+				(elevel_for_sub_disabled > NOTICE)
+				? errhint("Consider setting %s to false.",
+						  "retain_dead_tuples") : 0);
+}
+
 /*
  * Get the list of tables which belong to specified publications on the
  * publisher connection.
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index b8837f26cb4fd..cb811520c2959 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -2711,8 +2711,7 @@ MergeAttributes(List *columns, const List *supers, char relpersistence,
 							RelationGetRelationName(relation))));
 
 		/* If existing rel is temp, it must belong to this session */
-		if (relation->rd_rel->relpersistence == RELPERSISTENCE_TEMP &&
-			!relation->rd_islocaltemp)
+		if (RELATION_IS_OTHER_TEMP(relation))
 			ereport(ERROR,
 					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
 					 errmsg(!is_partition
@@ -15488,6 +15487,14 @@ ATPostAlterTypeCleanup(List **wqueue, AlteredTableInfo *tab, LOCKMODE lockmode)
 		Oid			relid;
 
 		relid = IndexGetRelation(oldId, false);
+
+		/*
+		 * As above, make sure we have lock on the index's table if it's not
+		 * the same table.
+		 */
+		if (relid != tab->relid)
+			LockRelationOid(relid, AccessExclusiveLock);
+
 		ATPostAlterTypeParse(oldId, relid, InvalidOid,
 							 (char *) lfirst(def_item),
 							 wqueue, lockmode, tab->rewrite);
@@ -15504,6 +15511,20 @@ ATPostAlterTypeCleanup(List **wqueue, AlteredTableInfo *tab, LOCKMODE lockmode)
 		Oid			relid;
 
 		relid = StatisticsGetRelation(oldId, false);
+
+		/*
+		 * As above, make sure we have lock on the statistics object's table
+		 * if it's not the same table.  However, we take
+		 * ShareUpdateExclusiveLock here, aligning with the lock level used in
+		 * CreateStatistics and RemoveStatisticsById.
+		 *
+		 * CAUTION: this should be done after all cases that grab
+		 * AccessExclusiveLock, else we risk causing deadlock due to needing
+		 * to promote our table lock.
+		 */
+		if (relid != tab->relid)
+			LockRelationOid(relid, ShareUpdateExclusiveLock);
+
 		ATPostAlterTypeParse(oldId, relid, InvalidOid,
 							 (char *) lfirst(def_item),
 							 wqueue, lockmode, tab->rewrite);
@@ -15727,7 +15748,7 @@ ATPostAlterTypeParse(Oid oldId, Oid oldRelId, Oid refRelId, char *cmd,
 		{
 			AlterDomainStmt *stmt = (AlterDomainStmt *) stm;
 
-			if (stmt->subtype == 'C')	/* ADD CONSTRAINT */
+			if (stmt->subtype == AD_AddConstraint)
 			{
 				Constraint *con = castNode(Constraint, stmt->def);
 				AlterTableCmd *cmd = makeNode(AlterTableCmd);
@@ -17230,15 +17251,13 @@ ATExecAddInherit(Relation child_rel, RangeVar *parent, LOCKMODE lockmode)
 						RelationGetRelationName(parent_rel))));
 
 	/* If parent rel is temp, it must belong to this session */
-	if (parent_rel->rd_rel->relpersistence == RELPERSISTENCE_TEMP &&
-		!parent_rel->rd_islocaltemp)
+	if (RELATION_IS_OTHER_TEMP(parent_rel))
 		ereport(ERROR,
 				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
 				 errmsg("cannot inherit from temporary relation of another session")));
 
 	/* Ditto for the child */
-	if (child_rel->rd_rel->relpersistence == RELPERSISTENCE_TEMP &&
-		!child_rel->rd_islocaltemp)
+	if (RELATION_IS_OTHER_TEMP(child_rel))
 		ereport(ERROR,
 				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
 				 errmsg("cannot inherit to temporary relation of another session")));
@@ -20309,15 +20328,13 @@ ATExecAttachPartition(List **wqueue, Relation rel, PartitionCmd *cmd,
 						RelationGetRelationName(rel))));
 
 	/* If the parent is temp, it must belong to this session */
-	if (rel->rd_rel->relpersistence == RELPERSISTENCE_TEMP &&
-		!rel->rd_islocaltemp)
+	if (RELATION_IS_OTHER_TEMP(rel))
 		ereport(ERROR,
 				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
 				 errmsg("cannot attach as partition of temporary relation of another session")));
 
 	/* Ditto for the partition */
-	if (attachrel->rd_rel->relpersistence == RELPERSISTENCE_TEMP &&
-		!attachrel->rd_islocaltemp)
+	if (RELATION_IS_OTHER_TEMP(attachrel))
 		ereport(ERROR,
 				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
 				 errmsg("cannot attach temporary relation of another session as partition")));
diff --git a/src/backend/commands/tablespace.c b/src/backend/commands/tablespace.c
index a9005cc7212b6..df31eace47ac9 100644
--- a/src/backend/commands/tablespace.c
+++ b/src/backend/commands/tablespace.c
@@ -500,7 +500,7 @@ DropTableSpace(DropTableSpaceStmt *stmt)
 		 * mustn't delete.  So instead, we force a checkpoint which will clean
 		 * out any lingering files, and try again.
 		 */
-		RequestCheckpoint(CHECKPOINT_IMMEDIATE | CHECKPOINT_FORCE | CHECKPOINT_WAIT);
+		RequestCheckpoint(CHECKPOINT_FAST | CHECKPOINT_FORCE | CHECKPOINT_WAIT);
 
 		/*
 		 * On Windows, an unlinked file persists in the directory listing
diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c
index 67f8e70f9c166..7dc121f73f17e 100644
--- a/src/backend/commands/trigger.c
+++ b/src/backend/commands/trigger.c
@@ -80,6 +80,7 @@ static bool GetTupleForTrigger(EState *estate,
 							   ItemPointer tid,
 							   LockTupleMode lockmode,
 							   TupleTableSlot *oldslot,
+							   bool do_epq_recheck,
 							   TupleTableSlot **epqslot,
 							   TM_Result *tmresultp,
 							   TM_FailureData *tmfdp);
@@ -2693,7 +2694,8 @@ ExecBRDeleteTriggers(EState *estate, EPQState *epqstate,
 					 HeapTuple fdw_trigtuple,
 					 TupleTableSlot **epqslot,
 					 TM_Result *tmresult,
-					 TM_FailureData *tmfd)
+					 TM_FailureData *tmfd,
+					 bool is_merge_delete)
 {
 	TupleTableSlot *slot = ExecGetTriggerOldSlot(estate, relinfo);
 	TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
@@ -2708,9 +2710,17 @@ ExecBRDeleteTriggers(EState *estate, EPQState *epqstate,
 	{
 		TupleTableSlot *epqslot_candidate = NULL;
 
+		/*
+		 * Get a copy of the on-disk tuple we are planning to delete.  In
+		 * general, if the tuple has been concurrently updated, we should
+		 * recheck it using EPQ.  However, if this is a MERGE DELETE action,
+		 * we skip this EPQ recheck and leave it to the caller (it must do
+		 * additional rechecking, and might end up executing a different
+		 * action entirely).
+		 */
 		if (!GetTupleForTrigger(estate, epqstate, relinfo, tupleid,
-								LockTupleExclusive, slot, &epqslot_candidate,
-								tmresult, tmfd))
+								LockTupleExclusive, slot, !is_merge_delete,
+								&epqslot_candidate, tmresult, tmfd))
 			return false;
 
 		/*
@@ -2800,6 +2810,7 @@ ExecARDeleteTriggers(EState *estate,
 							   tupleid,
 							   LockTupleExclusive,
 							   slot,
+							   false,
 							   NULL,
 							   NULL,
 							   NULL);
@@ -2944,7 +2955,8 @@ ExecBRUpdateTriggers(EState *estate, EPQState *epqstate,
 					 HeapTuple fdw_trigtuple,
 					 TupleTableSlot *newslot,
 					 TM_Result *tmresult,
-					 TM_FailureData *tmfd)
+					 TM_FailureData *tmfd,
+					 bool is_merge_update)
 {
 	TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
 	TupleTableSlot *oldslot = ExecGetTriggerOldSlot(estate, relinfo);
@@ -2965,10 +2977,17 @@ ExecBRUpdateTriggers(EState *estate, EPQState *epqstate,
 	{
 		TupleTableSlot *epqslot_candidate = NULL;
 
-		/* get a copy of the on-disk tuple we are planning to update */
+		/*
+		 * Get a copy of the on-disk tuple we are planning to update.  In
+		 * general, if the tuple has been concurrently updated, we should
+		 * recheck it using EPQ.  However, if this is a MERGE UPDATE action,
+		 * we skip this EPQ recheck and leave it to the caller (it must do
+		 * additional rechecking, and might end up executing a different
+		 * action entirely).
+		 */
 		if (!GetTupleForTrigger(estate, epqstate, relinfo, tupleid,
-								lockmode, oldslot, &epqslot_candidate,
-								tmresult, tmfd))
+								lockmode, oldslot, !is_merge_update,
+								&epqslot_candidate, tmresult, tmfd))
 			return false;		/* cancel the update action */
 
 		/*
@@ -3142,6 +3161,7 @@ ExecARUpdateTriggers(EState *estate, ResultRelInfo *relinfo,
 							   tupleid,
 							   LockTupleExclusive,
 							   oldslot,
+							   false,
 							   NULL,
 							   NULL,
 							   NULL);
@@ -3298,6 +3318,7 @@ GetTupleForTrigger(EState *estate,
 				   ItemPointer tid,
 				   LockTupleMode lockmode,
 				   TupleTableSlot *oldslot,
+				   bool do_epq_recheck,
 				   TupleTableSlot **epqslot,
 				   TM_Result *tmresultp,
 				   TM_FailureData *tmfdp)
@@ -3357,29 +3378,30 @@ GetTupleForTrigger(EState *estate,
 				if (tmfd.traversed)
 				{
 					/*
-					 * Recheck the tuple using EPQ. For MERGE, we leave this
-					 * to the caller (it must do additional rechecking, and
-					 * might end up executing a different action entirely).
+					 * Recheck the tuple using EPQ, if requested.  Otherwise,
+					 * just return that it was concurrently updated.
 					 */
-					if (estate->es_plannedstmt->commandType == CMD_MERGE)
+					if (do_epq_recheck)
 					{
-						if (tmresultp)
-							*tmresultp = TM_Updated;
-						return false;
+						*epqslot = EvalPlanQual(epqstate,
+												relation,
+												relinfo->ri_RangeTableIndex,
+												oldslot);
+
+						/*
+						 * If PlanQual failed for updated tuple - we must not
+						 * process this tuple!
+						 */
+						if (TupIsNull(*epqslot))
+						{
+							*epqslot = NULL;
+							return false;
+						}
 					}
-
-					*epqslot = EvalPlanQual(epqstate,
-											relation,
-											relinfo->ri_RangeTableIndex,
-											oldslot);
-
-					/*
-					 * If PlanQual failed for updated tuple - we must not
-					 * process this tuple!
-					 */
-					if (TupIsNull(*epqslot))
+					else
 					{
-						*epqslot = NULL;
+						if (tmresultp)
+							*tmresultp = TM_Updated;
 						return false;
 					}
 				}
diff --git a/src/backend/commands/typecmds.c b/src/backend/commands/typecmds.c
index 45ae7472ab5ad..26d985193aea4 100644
--- a/src/backend/commands/typecmds.c
+++ b/src/backend/commands/typecmds.c
@@ -939,11 +939,19 @@ DefineDomain(ParseState *pstate, CreateDomainStmt *stmt)
 				break;
 
 			case CONSTR_NOTNULL:
-				if (nullDefined && !typNotNull)
+				if (nullDefined)
+				{
+					if (!typNotNull)
+						ereport(ERROR,
+								errcode(ERRCODE_SYNTAX_ERROR),
+								errmsg("conflicting NULL/NOT NULL constraints"),
+								parser_errposition(pstate, constr->location));
+
 					ereport(ERROR,
-							errcode(ERRCODE_SYNTAX_ERROR),
-							errmsg("conflicting NULL/NOT NULL constraints"),
+							errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
+							errmsg("redundant NOT NULL constraint definition"),
 							parser_errposition(pstate, constr->location));
+				}
 				if (constr->is_no_inherit)
 					ereport(ERROR,
 							errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 02993d320dafc..733ef40ae7c52 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -124,7 +124,7 @@ static void vac_truncate_clog(TransactionId frozenXID,
 							  MultiXactId minMulti,
 							  TransactionId lastSaneFrozenXid,
 							  MultiXactId lastSaneMinMulti);
-static bool vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params,
+static bool vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 					   BufferAccessStrategy bstrategy);
 static double compute_parallel_delay(void);
 static VacOptValue get_vacoptval_from_boolean(DefElem *def);
@@ -465,7 +465,7 @@ ExecVacuum(ParseState *pstate, VacuumStmt *vacstmt, bool isTopLevel)
 	}
 
 	/* Now go through the common routine */
-	vacuum(vacstmt->rels, &params, bstrategy, vac_context, isTopLevel);
+	vacuum(vacstmt->rels, params, bstrategy, vac_context, isTopLevel);
 
 	/* Finally, clean up the vacuum memory context */
 	MemoryContextDelete(vac_context);
@@ -494,7 +494,7 @@ ExecVacuum(ParseState *pstate, VacuumStmt *vacstmt, bool isTopLevel)
  * memory context that will not disappear at transaction commit.
  */
 void
-vacuum(List *relations, VacuumParams *params, BufferAccessStrategy bstrategy,
+vacuum(List *relations, const VacuumParams params, BufferAccessStrategy bstrategy,
 	   MemoryContext vac_context, bool isTopLevel)
 {
 	static bool in_vacuum = false;
@@ -503,9 +503,7 @@ vacuum(List *relations, VacuumParams *params, BufferAccessStrategy bstrategy,
 	volatile bool in_outer_xact,
 				use_own_xacts;
 
-	Assert(params != NULL);
-
-	stmttype = (params->options & VACOPT_VACUUM) ? "VACUUM" : "ANALYZE";
+	stmttype = (params.options & VACOPT_VACUUM) ? "VACUUM" : "ANALYZE";
 
 	/*
 	 * We cannot run VACUUM inside a user transaction block; if we were inside
@@ -515,7 +513,7 @@ vacuum(List *relations, VacuumParams *params, BufferAccessStrategy bstrategy,
 	 *
 	 * ANALYZE (without VACUUM) can run either way.
 	 */
-	if (params->options & VACOPT_VACUUM)
+	if (params.options & VACOPT_VACUUM)
 	{
 		PreventInTransactionBlock(isTopLevel, stmttype);
 		in_outer_xact = false;
@@ -538,7 +536,7 @@ vacuum(List *relations, VacuumParams *params, BufferAccessStrategy bstrategy,
 	 * Build list of relation(s) to process, putting any new data in
 	 * vac_context for safekeeping.
 	 */
-	if (params->options & VACOPT_ONLY_DATABASE_STATS)
+	if (params.options & VACOPT_ONLY_DATABASE_STATS)
 	{
 		/* We don't process any tables in this case */
 		Assert(relations == NIL);
@@ -554,7 +552,7 @@ vacuum(List *relations, VacuumParams *params, BufferAccessStrategy bstrategy,
 			List	   *sublist;
 			MemoryContext old_context;
 
-			sublist = expand_vacuum_rel(vrel, vac_context, params->options);
+			sublist = expand_vacuum_rel(vrel, vac_context, params.options);
 			old_context = MemoryContextSwitchTo(vac_context);
 			newrels = list_concat(newrels, sublist);
 			MemoryContextSwitchTo(old_context);
@@ -562,7 +560,7 @@ vacuum(List *relations, VacuumParams *params, BufferAccessStrategy bstrategy,
 		relations = newrels;
 	}
 	else
-		relations = get_all_vacuum_rels(vac_context, params->options);
+		relations = get_all_vacuum_rels(vac_context, params.options);
 
 	/*
 	 * Decide whether we need to start/commit our own transactions.
@@ -578,11 +576,11 @@ vacuum(List *relations, VacuumParams *params, BufferAccessStrategy bstrategy,
 	 * transaction block, and also in an autovacuum worker, use own
 	 * transactions so we can release locks sooner.
 	 */
-	if (params->options & VACOPT_VACUUM)
+	if (params.options & VACOPT_VACUUM)
 		use_own_xacts = true;
 	else
 	{
-		Assert(params->options & VACOPT_ANALYZE);
+		Assert(params.options & VACOPT_ANALYZE);
 		if (AmAutoVacuumWorkerProcess())
 			use_own_xacts = true;
 		else if (in_outer_xact)
@@ -633,21 +631,13 @@ vacuum(List *relations, VacuumParams *params, BufferAccessStrategy bstrategy,
 		{
 			VacuumRelation *vrel = lfirst_node(VacuumRelation, cur);
 
-			if (params->options & VACOPT_VACUUM)
+			if (params.options & VACOPT_VACUUM)
 			{
-				VacuumParams params_copy;
-
-				/*
-				 * vacuum_rel() scribbles on the parameters, so give it a copy
-				 * to avoid affecting other relations.
-				 */
-				memcpy(&params_copy, params, sizeof(VacuumParams));
-
-				if (!vacuum_rel(vrel->oid, vrel->relation, &params_copy, bstrategy))
+				if (!vacuum_rel(vrel->oid, vrel->relation, params, bstrategy))
 					continue;
 			}
 
-			if (params->options & VACOPT_ANALYZE)
+			if (params.options & VACOPT_ANALYZE)
 			{
 				/*
 				 * If using separate xacts, start one for analyze. Otherwise,
@@ -711,8 +701,8 @@ vacuum(List *relations, VacuumParams *params, BufferAccessStrategy bstrategy,
 		StartTransactionCommand();
 	}
 
-	if ((params->options & VACOPT_VACUUM) &&
-		!(params->options & VACOPT_SKIP_DATABASE_STATS))
+	if ((params.options & VACOPT_VACUUM) &&
+		!(params.options & VACOPT_SKIP_DATABASE_STATS))
 	{
 		/*
 		 * Update pg_database.datfrozenxid, and truncate pg_xact if possible.
@@ -1110,7 +1100,7 @@ get_all_vacuum_rels(MemoryContext vac_context, int options)
  * minimum).
  */
 bool
-vacuum_get_cutoffs(Relation rel, const VacuumParams *params,
+vacuum_get_cutoffs(Relation rel, const VacuumParams params,
 				   struct VacuumCutoffs *cutoffs)
 {
 	int			freeze_min_age,
@@ -1126,10 +1116,10 @@ vacuum_get_cutoffs(Relation rel, const VacuumParams *params,
 				aggressiveMXIDCutoff;
 
 	/* Use mutable copies of freeze age parameters */
-	freeze_min_age = params->freeze_min_age;
-	multixact_freeze_min_age = params->multixact_freeze_min_age;
-	freeze_table_age = params->freeze_table_age;
-	multixact_freeze_table_age = params->multixact_freeze_table_age;
+	freeze_min_age = params.freeze_min_age;
+	multixact_freeze_min_age = params.multixact_freeze_min_age;
+	freeze_table_age = params.freeze_table_age;
+	multixact_freeze_table_age = params.multixact_freeze_table_age;
 
 	/* Set pg_class fields in cutoffs */
 	cutoffs->relfrozenxid = rel->rd_rel->relfrozenxid;
@@ -2006,7 +1996,7 @@ vac_truncate_clog(TransactionId frozenXID,
  *		At entry and exit, we are not inside a transaction.
  */
 static bool
-vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params,
+vacuum_rel(Oid relid, RangeVar *relation, VacuumParams params,
 		   BufferAccessStrategy bstrategy)
 {
 	LOCKMODE	lmode;
@@ -2019,18 +2009,16 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params,
 	int			save_nestlevel;
 	VacuumParams toast_vacuum_params;
 
-	Assert(params != NULL);
-
 	/*
 	 * This function scribbles on the parameters, so make a copy early to
 	 * avoid affecting the TOAST table (if we do end up recursing to it).
 	 */
-	memcpy(&toast_vacuum_params, params, sizeof(VacuumParams));
+	memcpy(&toast_vacuum_params, &params, sizeof(VacuumParams));
 
 	/* Begin a transaction for vacuuming this relation */
 	StartTransactionCommand();
 
-	if (!(params->options & VACOPT_FULL))
+	if (!(params.options & VACOPT_FULL))
 	{
 		/*
 		 * In lazy vacuum, we can set the PROC_IN_VACUUM flag, which lets
@@ -2056,7 +2044,7 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params,
 		 */
 		LWLockAcquire(ProcArrayLock, LW_EXCLUSIVE);
 		MyProc->statusFlags |= PROC_IN_VACUUM;
-		if (params->is_wraparound)
+		if (params.is_wraparound)
 			MyProc->statusFlags |= PROC_VACUUM_FOR_WRAPAROUND;
 		ProcGlobal->statusFlags[MyProc->pgxactoff] = MyProc->statusFlags;
 		LWLockRelease(ProcArrayLock);
@@ -2080,12 +2068,12 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params,
 	 * vacuum, but just ShareUpdateExclusiveLock for concurrent vacuum. Either
 	 * way, we can be sure that no other backend is vacuuming the same table.
 	 */
-	lmode = (params->options & VACOPT_FULL) ?
+	lmode = (params.options & VACOPT_FULL) ?
 		AccessExclusiveLock : ShareUpdateExclusiveLock;
 
 	/* open the relation and get the appropriate lock on it */
-	rel = vacuum_open_relation(relid, relation, params->options,
-							   params->log_min_duration >= 0, lmode);
+	rel = vacuum_open_relation(relid, relation, params.options,
+							   params.log_min_duration >= 0, lmode);
 
 	/* leave if relation could not be opened or locked */
 	if (!rel)
@@ -2100,8 +2088,8 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params,
 	 * This is only safe to do because we hold a session lock on the main
 	 * relation that prevents concurrent deletion.
 	 */
-	if (OidIsValid(params->toast_parent))
-		priv_relid = params->toast_parent;
+	if (OidIsValid(params.toast_parent))
+		priv_relid = params.toast_parent;
 	else
 		priv_relid = RelationGetRelid(rel);
 
@@ -2114,7 +2102,7 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params,
 	 */
 	if (!vacuum_is_permitted_for_relation(priv_relid,
 										  rel->rd_rel,
-										  params->options & ~VACOPT_ANALYZE))
+										  params.options & ~VACOPT_ANALYZE))
 	{
 		relation_close(rel, lmode);
 		PopActiveSnapshot();
@@ -2185,7 +2173,7 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params,
 	 * Set index_cleanup option based on index_cleanup reloption if it wasn't
 	 * specified in VACUUM command, or when running in an autovacuum worker
 	 */
-	if (params->index_cleanup == VACOPTVALUE_UNSPECIFIED)
+	if (params.index_cleanup == VACOPTVALUE_UNSPECIFIED)
 	{
 		StdRdOptIndexCleanup vacuum_index_cleanup;
 
@@ -2196,23 +2184,23 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params,
 				((StdRdOptions *) rel->rd_options)->vacuum_index_cleanup;
 
 		if (vacuum_index_cleanup == STDRD_OPTION_VACUUM_INDEX_CLEANUP_AUTO)
-			params->index_cleanup = VACOPTVALUE_AUTO;
+			params.index_cleanup = VACOPTVALUE_AUTO;
 		else if (vacuum_index_cleanup == STDRD_OPTION_VACUUM_INDEX_CLEANUP_ON)
-			params->index_cleanup = VACOPTVALUE_ENABLED;
+			params.index_cleanup = VACOPTVALUE_ENABLED;
 		else
 		{
 			Assert(vacuum_index_cleanup ==
 				   STDRD_OPTION_VACUUM_INDEX_CLEANUP_OFF);
-			params->index_cleanup = VACOPTVALUE_DISABLED;
+			params.index_cleanup = VACOPTVALUE_DISABLED;
 		}
 	}
 
 #ifdef USE_INJECTION_POINTS
-	if (params->index_cleanup == VACOPTVALUE_AUTO)
+	if (params.index_cleanup == VACOPTVALUE_AUTO)
 		INJECTION_POINT("vacuum-index-cleanup-auto", NULL);
-	else if (params->index_cleanup == VACOPTVALUE_DISABLED)
+	else if (params.index_cleanup == VACOPTVALUE_DISABLED)
 		INJECTION_POINT("vacuum-index-cleanup-disabled", NULL);
-	else if (params->index_cleanup == VACOPTVALUE_ENABLED)
+	else if (params.index_cleanup == VACOPTVALUE_ENABLED)
 		INJECTION_POINT("vacuum-index-cleanup-enabled", NULL);
 #endif
 
@@ -2222,36 +2210,36 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params,
 	 */
 	if (rel->rd_options != NULL &&
 		((StdRdOptions *) rel->rd_options)->vacuum_max_eager_freeze_failure_rate >= 0)
-		params->max_eager_freeze_failure_rate =
+		params.max_eager_freeze_failure_rate =
 			((StdRdOptions *) rel->rd_options)->vacuum_max_eager_freeze_failure_rate;
 
 	/*
 	 * Set truncate option based on truncate reloption or GUC if it wasn't
 	 * specified in VACUUM command, or when running in an autovacuum worker
 	 */
-	if (params->truncate == VACOPTVALUE_UNSPECIFIED)
+	if (params.truncate == VACOPTVALUE_UNSPECIFIED)
 	{
 		StdRdOptions *opts = (StdRdOptions *) rel->rd_options;
 
 		if (opts && opts->vacuum_truncate_set)
 		{
 			if (opts->vacuum_truncate)
-				params->truncate = VACOPTVALUE_ENABLED;
+				params.truncate = VACOPTVALUE_ENABLED;
 			else
-				params->truncate = VACOPTVALUE_DISABLED;
+				params.truncate = VACOPTVALUE_DISABLED;
 		}
 		else if (vacuum_truncate)
-			params->truncate = VACOPTVALUE_ENABLED;
+			params.truncate = VACOPTVALUE_ENABLED;
 		else
-			params->truncate = VACOPTVALUE_DISABLED;
+			params.truncate = VACOPTVALUE_DISABLED;
 	}
 
 #ifdef USE_INJECTION_POINTS
-	if (params->truncate == VACOPTVALUE_AUTO)
+	if (params.truncate == VACOPTVALUE_AUTO)
 		INJECTION_POINT("vacuum-truncate-auto", NULL);
-	else if (params->truncate == VACOPTVALUE_DISABLED)
+	else if (params.truncate == VACOPTVALUE_DISABLED)
 		INJECTION_POINT("vacuum-truncate-disabled", NULL);
-	else if (params->truncate == VACOPTVALUE_ENABLED)
+	else if (params.truncate == VACOPTVALUE_ENABLED)
 		INJECTION_POINT("vacuum-truncate-enabled", NULL);
 #endif
 
@@ -2261,9 +2249,9 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params,
 	 * automatically rebuilt by cluster_rel so we shouldn't recurse to it,
 	 * unless PROCESS_MAIN is disabled.
 	 */
-	if ((params->options & VACOPT_PROCESS_TOAST) != 0 &&
-		((params->options & VACOPT_FULL) == 0 ||
-		 (params->options & VACOPT_PROCESS_MAIN) == 0))
+	if ((params.options & VACOPT_PROCESS_TOAST) != 0 &&
+		((params.options & VACOPT_FULL) == 0 ||
+		 (params.options & VACOPT_PROCESS_MAIN) == 0))
 		toast_relid = rel->rd_rel->reltoastrelid;
 	else
 		toast_relid = InvalidOid;
@@ -2286,16 +2274,16 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params,
 	 * table is required (e.g., PROCESS_TOAST is set), we force PROCESS_MAIN
 	 * to be set when we recurse to the TOAST table.
 	 */
-	if (params->options & VACOPT_PROCESS_MAIN)
+	if (params.options & VACOPT_PROCESS_MAIN)
 	{
 		/*
 		 * Do the actual work --- either FULL or "lazy" vacuum
 		 */
-		if (params->options & VACOPT_FULL)
+		if (params.options & VACOPT_FULL)
 		{
 			ClusterParams cluster_params = {0};
 
-			if ((params->options & VACOPT_VERBOSE) != 0)
+			if ((params.options & VACOPT_VERBOSE) != 0)
 				cluster_params.options |= CLUOPT_VERBOSE;
 
 			/* VACUUM FULL is now a variant of CLUSTER; see cluster.c */
@@ -2342,7 +2330,7 @@ vacuum_rel(Oid relid, RangeVar *relation, VacuumParams *params,
 		toast_vacuum_params.options |= VACOPT_PROCESS_MAIN;
 		toast_vacuum_params.toast_parent = relid;
 
-		vacuum_rel(toast_relid, NULL, &toast_vacuum_params, bstrategy);
+		vacuum_rel(toast_relid, NULL, toast_vacuum_params, bstrategy);
 	}
 
 	/*
diff --git a/src/backend/executor/execExprInterp.c b/src/backend/executor/execExprInterp.c
index 8a72b5e70a4ec..1a37737d4a235 100644
--- a/src/backend/executor/execExprInterp.c
+++ b/src/backend/executor/execExprInterp.c
@@ -5228,7 +5228,6 @@ ExecEvalJsonCoercionFinish(ExprState *state, ExprEvalStep *op)
 		 * JsonBehavior expression.
 		 */
 		jsestate->escontext.error_occurred = false;
-		jsestate->escontext.error_occurred = false;
 		jsestate->escontext.details_wanted = true;
 	}
 }
diff --git a/src/backend/executor/execIndexing.c b/src/backend/executor/execIndexing.c
index bdf862b24062e..ca33a854278ed 100644
--- a/src/backend/executor/execIndexing.c
+++ b/src/backend/executor/execIndexing.c
@@ -279,7 +279,7 @@ ExecCloseIndices(ResultRelInfo *resultRelInfo)
  *		executor is performing an UPDATE that could not use an
  *		optimization like heapam's HOT (in more general terms a
  *		call to table_tuple_update() took place and set
- *		'update_indexes' to TUUI_All).  Receiving this hint makes
+ *		'update_indexes' to TU_All).  Receiving this hint makes
  *		us consider if we should pass down the 'indexUnchanged'
  *		hint in turn.  That's something that we figure out for
  *		each index_insert() call iff 'update' is true.
@@ -290,7 +290,7 @@ ExecCloseIndices(ResultRelInfo *resultRelInfo)
  *		HOT has been applied and any updated columns are indexed
  *		only by summarizing indexes (or in more general terms a
  *		call to table_tuple_update() took place and set
- *		'update_indexes' to TUUI_Summarizing). We can (and must)
+ *		'update_indexes' to TU_Summarizing). We can (and must)
  *		therefore only update the indexes that have
  *		'amsummarizing' = true.
  *
diff --git a/src/backend/executor/execParallel.c b/src/backend/executor/execParallel.c
index f3e77bda27906..f098a5557cf07 100644
--- a/src/backend/executor/execParallel.c
+++ b/src/backend/executor/execParallel.c
@@ -189,6 +189,7 @@ ExecSerializePlan(Plan *plan, EState *estate)
 	pstmt->permInfos = estate->es_rteperminfos;
 	pstmt->resultRelations = NIL;
 	pstmt->appendRelations = NIL;
+	pstmt->planOrigin = PLAN_STMT_INTERNAL;
 
 	/*
 	 * Transfer only parallel-safe subplans, leaving a NULL "hole" in the list
diff --git a/src/backend/executor/execReplication.c b/src/backend/executor/execReplication.c
index 53ddd25c42db9..68184f5d671e2 100644
--- a/src/backend/executor/execReplication.c
+++ b/src/backend/executor/execReplication.c
@@ -14,12 +14,14 @@
 
 #include "postgres.h"
 
+#include "access/commit_ts.h"
 #include "access/genam.h"
 #include "access/gist.h"
 #include "access/relscan.h"
 #include "access/tableam.h"
 #include "access/transam.h"
 #include "access/xact.h"
+#include "access/heapam.h"
 #include "catalog/pg_am_d.h"
 #include "commands/trigger.h"
 #include "executor/executor.h"
@@ -36,7 +38,7 @@
 
 
 static bool tuples_equal(TupleTableSlot *slot1, TupleTableSlot *slot2,
-						 TypeCacheEntry **eq);
+						 TypeCacheEntry **eq, Bitmapset *columns);
 
 /*
  * Setup a ScanKey for a search in the relation 'rel' for a tuple 'key' that
@@ -221,7 +223,7 @@ RelationFindReplTupleByIndex(Relation rel, Oid idxoid,
 			if (eq == NULL)
 				eq = palloc0(sizeof(*eq) * outslot->tts_tupleDescriptor->natts);
 
-			if (!tuples_equal(outslot, searchslot, eq))
+			if (!tuples_equal(outslot, searchslot, eq, NULL))
 				continue;
 		}
 
@@ -277,10 +279,13 @@ RelationFindReplTupleByIndex(Relation rel, Oid idxoid,
 
 /*
  * Compare the tuples in the slots by checking if they have equal values.
+ *
+ * If 'columns' is not null, only the columns specified within it will be
+ * considered for the equality check, ignoring all other columns.
  */
 static bool
 tuples_equal(TupleTableSlot *slot1, TupleTableSlot *slot2,
-			 TypeCacheEntry **eq)
+			 TypeCacheEntry **eq, Bitmapset *columns)
 {
 	int			attrnum;
 
@@ -305,6 +310,14 @@ tuples_equal(TupleTableSlot *slot1, TupleTableSlot *slot2,
 		if (att->attisdropped || att->attgenerated)
 			continue;
 
+		/*
+		 * Ignore columns that are not listed for checking.
+		 */
+		if (columns &&
+			!bms_is_member(att->attnum - FirstLowInvalidHeapAttributeNumber,
+						   columns))
+			continue;
+
 		/*
 		 * If one value is NULL and other is not, then they are certainly not
 		 * equal
@@ -380,7 +393,7 @@ RelationFindReplTupleSeq(Relation rel, LockTupleMode lockmode,
 	/* Try to find the tuple */
 	while (table_scan_getnextslot(scan, ForwardScanDirection, scanslot))
 	{
-		if (!tuples_equal(scanslot, searchslot, eq))
+		if (!tuples_equal(scanslot, searchslot, eq, NULL))
 			continue;
 
 		found = true;
@@ -455,6 +468,236 @@ BuildConflictIndexInfo(ResultRelInfo *resultRelInfo, Oid conflictindex)
 	}
 }
 
+/*
+ * If the tuple is recently dead and was deleted by a transaction with a newer
+ * commit timestamp than previously recorded, update the associated transaction
+ * ID, commit time, and origin. This helps ensure that conflict detection uses
+ * the most recent and relevant deletion metadata.
+ */
+static void
+update_most_recent_deletion_info(TupleTableSlot *scanslot,
+								 TransactionId oldestxmin,
+								 TransactionId *delete_xid,
+								 TimestampTz *delete_time,
+								 RepOriginId *delete_origin)
+{
+	BufferHeapTupleTableSlot *hslot;
+	HeapTuple	tuple;
+	Buffer		buf;
+	bool		recently_dead = false;
+	TransactionId xmax;
+	TimestampTz localts;
+	RepOriginId localorigin;
+
+	hslot = (BufferHeapTupleTableSlot *) scanslot;
+
+	tuple = ExecFetchSlotHeapTuple(scanslot, false, NULL);
+	buf = hslot->buffer;
+
+	LockBuffer(buf, BUFFER_LOCK_SHARE);
+
+	/*
+	 * We do not consider HEAPTUPLE_DEAD status because it indicates either
+	 * tuples whose inserting transaction was aborted (meaning there is no
+	 * commit timestamp or origin), or tuples deleted by a transaction older
+	 * than oldestxmin, making it safe to ignore them during conflict
+	 * detection (See comments atop worker.c for details).
+	 */
+	if (HeapTupleSatisfiesVacuum(tuple, oldestxmin, buf) == HEAPTUPLE_RECENTLY_DEAD)
+		recently_dead = true;
+
+	LockBuffer(buf, BUFFER_LOCK_UNLOCK);
+
+	if (!recently_dead)
+		return;
+
+	xmax = HeapTupleHeaderGetUpdateXid(tuple->t_data);
+	if (!TransactionIdIsValid(xmax))
+		return;
+
+	/* Select the dead tuple with the most recent commit timestamp */
+	if (TransactionIdGetCommitTsData(xmax, &localts, &localorigin) &&
+		TimestampDifferenceExceeds(*delete_time, localts, 0))
+	{
+		*delete_xid = xmax;
+		*delete_time = localts;
+		*delete_origin = localorigin;
+	}
+}
+
+/*
+ * Searches the relation 'rel' for the most recently deleted tuple that matches
+ * the values in 'searchslot' and is not yet removable by VACUUM. The function
+ * returns the transaction ID, origin, and commit timestamp of the transaction
+ * that deleted this tuple.
+ *
+ * 'oldestxmin' acts as a cutoff transaction ID. Tuples deleted by transactions
+ * with IDs >= 'oldestxmin' are considered recently dead and are eligible for
+ * conflict detection.
+ *
+ * Instead of stopping at the first match, we scan all matching dead tuples to
+ * identify most recent deletion. This is crucial because only the latest
+ * deletion is relevant for resolving conflicts.
+ *
+ * For example, consider a scenario on the subscriber where a row is deleted,
+ * re-inserted, and then deleted again only on the subscriber:
+ *
+ *   - (pk, 1) - deleted at 9:00,
+ *   - (pk, 1) - deleted at 9:02,
+ *
+ * Now, a remote update arrives: (pk, 1) -> (pk, 2), timestamped at 9:01.
+ *
+ * If we mistakenly return the older deletion (9:00), the system may wrongly
+ * apply the remote update using a last-update-wins strategy. Instead, we must
+ * recognize the more recent deletion at 9:02 and skip the update. See
+ * comments atop worker.c for details. Note, as of now, conflict resolution
+ * is not implemented. Consequently, the system may incorrectly report the
+ * older tuple as the conflicted one, leading to misleading results.
+ *
+ * The commit timestamp of the deleting transaction is used to determine which
+ * tuple was deleted most recently.
+ */
+bool
+RelationFindDeletedTupleInfoSeq(Relation rel, TupleTableSlot *searchslot,
+								TransactionId oldestxmin,
+								TransactionId *delete_xid,
+								RepOriginId *delete_origin,
+								TimestampTz *delete_time)
+{
+	TupleTableSlot *scanslot;
+	TableScanDesc scan;
+	TypeCacheEntry **eq;
+	Bitmapset  *indexbitmap;
+	TupleDesc	desc PG_USED_FOR_ASSERTS_ONLY = RelationGetDescr(rel);
+
+	Assert(equalTupleDescs(desc, searchslot->tts_tupleDescriptor));
+
+	*delete_xid = InvalidTransactionId;
+	*delete_origin = InvalidRepOriginId;
+	*delete_time = 0;
+
+	/*
+	 * If the relation has a replica identity key or a primary key that is
+	 * unusable for locating deleted tuples (see
+	 * IsIndexUsableForFindingDeletedTuple), a full table scan becomes
+	 * necessary. In such cases, comparing the entire tuple is not required,
+	 * since the remote tuple might not include all column values. Instead,
+	 * the indexed columns alone are suffcient to identify the target tuple
+	 * (see logicalrep_rel_mark_updatable).
+	 */
+	indexbitmap = RelationGetIndexAttrBitmap(rel,
+											 INDEX_ATTR_BITMAP_IDENTITY_KEY);
+
+	/* fallback to PK if no replica identity */
+	if (!indexbitmap)
+		indexbitmap = RelationGetIndexAttrBitmap(rel,
+												 INDEX_ATTR_BITMAP_PRIMARY_KEY);
+
+	eq = palloc0(sizeof(*eq) * searchslot->tts_tupleDescriptor->natts);
+
+	/*
+	 * Start a heap scan using SnapshotAny to identify dead tuples that are
+	 * not visible under a standard MVCC snapshot. Tuples from transactions
+	 * not yet committed or those just committed prior to the scan are
+	 * excluded in update_most_recent_deletion_info().
+	 */
+	scan = table_beginscan(rel, SnapshotAny, 0, NULL);
+	scanslot = table_slot_create(rel, NULL);
+
+	table_rescan(scan, NULL);
+
+	/* Try to find the tuple */
+	while (table_scan_getnextslot(scan, ForwardScanDirection, scanslot))
+	{
+		if (!tuples_equal(scanslot, searchslot, eq, indexbitmap))
+			continue;
+
+		update_most_recent_deletion_info(scanslot, oldestxmin, delete_xid,
+										 delete_time, delete_origin);
+	}
+
+	table_endscan(scan);
+	ExecDropSingleTupleTableSlot(scanslot);
+
+	return *delete_time != 0;
+}
+
+/*
+ * Similar to RelationFindDeletedTupleInfoSeq() but using index scan to locate
+ * the deleted tuple.
+ */
+bool
+RelationFindDeletedTupleInfoByIndex(Relation rel, Oid idxoid,
+									TupleTableSlot *searchslot,
+									TransactionId oldestxmin,
+									TransactionId *delete_xid,
+									RepOriginId *delete_origin,
+									TimestampTz *delete_time)
+{
+	Relation	idxrel;
+	ScanKeyData skey[INDEX_MAX_KEYS];
+	int			skey_attoff;
+	IndexScanDesc scan;
+	TupleTableSlot *scanslot;
+	TypeCacheEntry **eq = NULL;
+	bool		isIdxSafeToSkipDuplicates;
+	TupleDesc	desc PG_USED_FOR_ASSERTS_ONLY = RelationGetDescr(rel);
+
+	Assert(equalTupleDescs(desc, searchslot->tts_tupleDescriptor));
+	Assert(OidIsValid(idxoid));
+
+	*delete_xid = InvalidTransactionId;
+	*delete_time = 0;
+	*delete_origin = InvalidRepOriginId;
+
+	isIdxSafeToSkipDuplicates = (GetRelationIdentityOrPK(rel) == idxoid);
+
+	scanslot = table_slot_create(rel, NULL);
+
+	idxrel = index_open(idxoid, RowExclusiveLock);
+
+	/* Build scan key. */
+	skey_attoff = build_replindex_scan_key(skey, rel, idxrel, searchslot);
+
+	/*
+	 * Start an index scan using SnapshotAny to identify dead tuples that are
+	 * not visible under a standard MVCC snapshot. Tuples from transactions
+	 * not yet committed or those just committed prior to the scan are
+	 * excluded in update_most_recent_deletion_info().
+	 */
+	scan = index_beginscan(rel, idxrel, SnapshotAny, NULL, skey_attoff, 0);
+
+	index_rescan(scan, skey, skey_attoff, NULL, 0);
+
+	/* Try to find the tuple */
+	while (index_getnext_slot(scan, ForwardScanDirection, scanslot))
+	{
+		/*
+		 * Avoid expensive equality check if the index is primary key or
+		 * replica identity index.
+		 */
+		if (!isIdxSafeToSkipDuplicates)
+		{
+			if (eq == NULL)
+				eq = palloc0(sizeof(*eq) * scanslot->tts_tupleDescriptor->natts);
+
+			if (!tuples_equal(scanslot, searchslot, eq, NULL))
+				continue;
+		}
+
+		update_most_recent_deletion_info(scanslot, oldestxmin, delete_xid,
+										 delete_time, delete_origin);
+	}
+
+	index_endscan(scan);
+
+	index_close(idxrel, NoLock);
+
+	ExecDropSingleTupleTableSlot(scanslot);
+
+	return *delete_time != 0;
+}
+
 /*
  * Find the tuple that violates the passed unique index (conflictindex).
  *
@@ -670,7 +913,7 @@ ExecSimpleRelationUpdate(ResultRelInfo *resultRelInfo,
 		resultRelInfo->ri_TrigDesc->trig_update_before_row)
 	{
 		if (!ExecBRUpdateTriggers(estate, epqstate, resultRelInfo,
-								  tid, NULL, slot, NULL, NULL))
+								  tid, NULL, slot, NULL, NULL, false))
 			skip_tuple = true;	/* "do nothing" */
 	}
 
@@ -746,7 +989,7 @@ ExecSimpleRelationDelete(ResultRelInfo *resultRelInfo,
 		resultRelInfo->ri_TrigDesc->trig_delete_before_row)
 	{
 		skip_tuple = !ExecBRDeleteTriggers(estate, epqstate, resultRelInfo,
-										   tid, NULL, NULL, NULL, NULL);
+										   tid, NULL, NULL, NULL, NULL, false);
 	}
 
 	if (!skip_tuple)
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 54da8e7995bd3..7c6c2c1f6e42a 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1474,7 +1474,8 @@ ExecDeletePrologue(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
 
 		return ExecBRDeleteTriggers(context->estate, context->epqstate,
 									resultRelInfo, tupleid, oldtuple,
-									epqreturnslot, result, &context->tmfd);
+									epqreturnslot, result, &context->tmfd,
+									context->mtstate->operation == CMD_MERGE);
 	}
 
 	return true;
@@ -2117,7 +2118,8 @@ ExecUpdatePrologue(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
 
 		return ExecBRUpdateTriggers(context->estate, context->epqstate,
 									resultRelInfo, tupleid, oldtuple, slot,
-									result, &context->tmfd);
+									result, &context->tmfd,
+									context->mtstate->operation == CMD_MERGE);
 	}
 
 	return true;
diff --git a/src/backend/jit/llvm/Makefile b/src/backend/jit/llvm/Makefile
index e8c12060b93df..68677ba42e189 100644
--- a/src/backend/jit/llvm/Makefile
+++ b/src/backend/jit/llvm/Makefile
@@ -31,7 +31,7 @@ endif
 # All files in this directory use LLVM.
 CFLAGS += $(LLVM_CFLAGS)
 CXXFLAGS += $(LLVM_CXXFLAGS)
-override CPPFLAGS := $(LLVM_CPPFLAGS) $(CPPFLAGS)
+override CPPFLAGS += $(LLVM_CPPFLAGS)
 SHLIB_LINK += $(LLVM_LIBS)
 
 # Because this module includes C++ files, we need to use a C++
diff --git a/src/backend/jit/llvm/meson.build b/src/backend/jit/llvm/meson.build
index c8e06dfbe351b..805fbd6900679 100644
--- a/src/backend/jit/llvm/meson.build
+++ b/src/backend/jit/llvm/meson.build
@@ -53,7 +53,7 @@ llvm_irgen_args = [
 
 if ccache.found()
   llvm_irgen_command = ccache
-  llvm_irgen_args = [clang.path()] + llvm_irgen_args
+  llvm_irgen_args = [clang.full_path()] + llvm_irgen_args
 else
   llvm_irgen_command = clang
 endif
diff --git a/src/backend/libpq/auth.c b/src/backend/libpq/auth.c
index 9f4d05ffbd453..4da46666439db 100644
--- a/src/backend/libpq/auth.c
+++ b/src/backend/libpq/auth.c
@@ -94,8 +94,16 @@ static int	auth_peer(hbaPort *port);
 
 #define PGSQL_PAM_SERVICE "postgresql"	/* Service name passed to PAM */
 
+/* Work around original Solaris' lack of "const" in the conv_proc signature */
+#ifdef _PAM_LEGACY_NONCONST
+#define PG_PAM_CONST
+#else
+#define PG_PAM_CONST const
+#endif
+
 static int	CheckPAMAuth(Port *port, const char *user, const char *password);
-static int	pam_passwd_conv_proc(int num_msg, const struct pam_message **msg,
+static int	pam_passwd_conv_proc(int num_msg,
+								 PG_PAM_CONST struct pam_message **msg,
 								 struct pam_response **resp, void *appdata_ptr);
 
 static struct pam_conv pam_passw_conv = {
@@ -1917,7 +1925,7 @@ auth_peer(hbaPort *port)
  */
 
 static int
-pam_passwd_conv_proc(int num_msg, const struct pam_message **msg,
+pam_passwd_conv_proc(int num_msg, PG_PAM_CONST struct pam_message **msg,
 					 struct pam_response **resp, void *appdata_ptr)
 {
 	const char *passwd;
diff --git a/src/backend/libpq/hba.c b/src/backend/libpq/hba.c
index 332fad278351c..fecee8224d075 100644
--- a/src/backend/libpq/hba.c
+++ b/src/backend/libpq/hba.c
@@ -2873,8 +2873,11 @@ check_ident_usermap(IdentLine *identLine, const char *usermap_name,
 			!token_has_regexp(identLine->pg_user) &&
 			(ofs = strstr(identLine->pg_user->string, "\\1")) != NULL)
 		{
+			const char *repl_str;
+			size_t		repl_len;
+			char	   *old_pg_user;
 			char	   *expanded_pg_user;
-			int			offset;
+			size_t		offset;
 
 			/* substitution of the first argument requested */
 			if (matches[1].rm_so < 0)
@@ -2886,18 +2889,33 @@ check_ident_usermap(IdentLine *identLine, const char *usermap_name,
 				*error_p = true;
 				return;
 			}
+			repl_str = system_user + matches[1].rm_so;
+			repl_len = matches[1].rm_eo - matches[1].rm_so;
 
 			/*
-			 * length: original length minus length of \1 plus length of match
-			 * plus null terminator
+			 * It's allowed to have more than one \1 in the string, and we'll
+			 * replace them all.  But that's pretty unusual so we optimize on
+			 * the assumption of only one occurrence, which motivates doing
+			 * repeated replacements instead of making two passes over the
+			 * string to determine the final length right away.
 			 */
-			expanded_pg_user = palloc0(strlen(identLine->pg_user->string) - 2 + (matches[1].rm_eo - matches[1].rm_so) + 1);
-			offset = ofs - identLine->pg_user->string;
-			memcpy(expanded_pg_user, identLine->pg_user->string, offset);
-			memcpy(expanded_pg_user + offset,
-				   system_user + matches[1].rm_so,
-				   matches[1].rm_eo - matches[1].rm_so);
-			strcat(expanded_pg_user, ofs + 2);
+			old_pg_user = identLine->pg_user->string;
+			do
+			{
+				/*
+				 * length: current length minus length of \1 plus length of
+				 * replacement plus null terminator
+				 */
+				expanded_pg_user = palloc(strlen(old_pg_user) - 2 + repl_len + 1);
+				/* ofs points into the old_pg_user string at this point */
+				offset = ofs - old_pg_user;
+				memcpy(expanded_pg_user, old_pg_user, offset);
+				memcpy(expanded_pg_user + offset, repl_str, repl_len);
+				strcpy(expanded_pg_user + offset + repl_len, ofs + 2);
+				if (old_pg_user != identLine->pg_user->string)
+					pfree(old_pg_user);
+				old_pg_user = expanded_pg_user;
+			} while ((ofs = strstr(old_pg_user + offset + repl_len, "\\1")) != NULL);
 
 			/*
 			 * Mark the token as quoted, so it will only be compared literally
diff --git a/src/backend/libpq/pg_ident.conf.sample b/src/backend/libpq/pg_ident.conf.sample
index f5225f26cdf2c..8ee6c0ba31576 100644
--- a/src/backend/libpq/pg_ident.conf.sample
+++ b/src/backend/libpq/pg_ident.conf.sample
@@ -13,25 +13,25 @@
 # user names to their corresponding PostgreSQL user names.  Records
 # are of the form:
 #
-# MAPNAME  SYSTEM-USERNAME  PG-USERNAME
+# MAPNAME  SYSTEM-USERNAME  DATABASE-USERNAME
 #
 # (The uppercase quantities must be replaced by actual values.)
 #
 # MAPNAME is the (otherwise freely chosen) map name that was used in
 # pg_hba.conf.  SYSTEM-USERNAME is the detected user name of the
-# client.  PG-USERNAME is the requested PostgreSQL user name.  The
-# existence of a record specifies that SYSTEM-USERNAME may connect as
-# PG-USERNAME.
+# client.  DATABASE-USERNAME is the requested PostgreSQL user name.
+# The existence of a record specifies that SYSTEM-USERNAME may connect
+# as DATABASE-USERNAME.
 #
-# If SYSTEM-USERNAME starts with a slash (/), it will be treated as a
-# regular expression.  Optionally this can contain a capture (a
-# parenthesized subexpression).  The substring matching the capture
-# will be substituted for \1 (backslash-one) if present in
-# PG-USERNAME.
+# If SYSTEM-USERNAME starts with a slash (/), the rest of it will be
+# treated as a regular expression.  Optionally this can contain a capture
+# (a parenthesized subexpression).  The substring matching the capture
+# will be substituted for \1 (backslash-one) if that appears in
+# DATABASE-USERNAME.
 #
-# PG-USERNAME can be "all", a user name, a group name prefixed with "+", or
-# a regular expression (if it starts with a slash (/)).  If it is a regular
-# expression, the substring matching with \1 has no effect.
+# DATABASE-USERNAME can be "all", a user name, a group name prefixed with "+",
+# or a regular expression (if it starts with a slash (/)).  If it is a regular
+# expression, no substitution for \1 will occur.
 #
 # Multiple maps may be specified in this file and used by pg_hba.conf.
 #
@@ -69,4 +69,4 @@
 # Put your actual configuration here
 # ----------------------------------
 
-# MAPNAME       SYSTEM-USERNAME         PG-USERNAME
+# MAPNAME       SYSTEM-USERNAME         DATABASE-USERNAME
diff --git a/src/backend/libpq/pqcomm.c b/src/backend/libpq/pqcomm.c
index e5171467de18d..25f739a6a17d4 100644
--- a/src/backend/libpq/pqcomm.c
+++ b/src/backend/libpq/pqcomm.c
@@ -858,7 +858,6 @@ RemoveSocketFiles(void)
 		(void) unlink(sock_path);
 	}
 	/* Since we're about to exit, no need to reclaim storage */
-	sock_paths = NIL;
 }
 
 
diff --git a/src/backend/libpq/pqmq.c b/src/backend/libpq/pqmq.c
index f1a08bc32ca17..5f39949a36773 100644
--- a/src/backend/libpq/pqmq.c
+++ b/src/backend/libpq/pqmq.c
@@ -23,7 +23,7 @@
 #include "tcop/tcopprot.h"
 #include "utils/builtins.h"
 
-static shm_mq_handle *pq_mq_handle;
+static shm_mq_handle *pq_mq_handle = NULL;
 static bool pq_mq_busy = false;
 static pid_t pq_mq_parallel_leader_pid = 0;
 static ProcNumber pq_mq_parallel_leader_proc_number = INVALID_PROC_NUMBER;
@@ -66,7 +66,11 @@ pq_redirect_to_shm_mq(dsm_segment *seg, shm_mq_handle *mqh)
 static void
 pq_cleanup_redirect_to_shm_mq(dsm_segment *seg, Datum arg)
 {
-	pq_mq_handle = NULL;
+	if (pq_mq_handle != NULL)
+	{
+		pfree(pq_mq_handle);
+		pq_mq_handle = NULL;
+	}
 	whereToSendOutput = DestNone;
 }
 
@@ -131,8 +135,11 @@ mq_putmessage(char msgtype, const char *s, size_t len)
 	if (pq_mq_busy)
 	{
 		if (pq_mq_handle != NULL)
+		{
 			shm_mq_detach(pq_mq_handle);
-		pq_mq_handle = NULL;
+			pfree(pq_mq_handle);
+			pq_mq_handle = NULL;
+		}
 		return EOF;
 	}
 
@@ -152,8 +159,6 @@ mq_putmessage(char msgtype, const char *s, size_t len)
 	iov[1].data = s;
 	iov[1].len = len;
 
-	Assert(pq_mq_handle != NULL);
-
 	for (;;)
 	{
 		/*
@@ -161,6 +166,7 @@ mq_putmessage(char msgtype, const char *s, size_t len)
 		 * that the shared memory value is updated before we send the parallel
 		 * message signal right after this.
 		 */
+		Assert(pq_mq_handle != NULL);
 		result = shm_mq_sendv(pq_mq_handle, iov, 2, true, true);
 
 		if (pq_mq_parallel_leader_pid != 0)
diff --git a/src/backend/main/main.c b/src/backend/main/main.c
index 7d63cf94a6b44..bdcb5e4f26159 100644
--- a/src/backend/main/main.c
+++ b/src/backend/main/main.c
@@ -125,13 +125,17 @@ main(int argc, char *argv[])
 	set_pglocale_pgservice(argv[0], PG_TEXTDOMAIN("postgres"));
 
 	/*
-	 * In the postmaster, absorb the environment values for LC_COLLATE and
-	 * LC_CTYPE.  Individual backends will change these later to settings
-	 * taken from pg_database, but the postmaster cannot do that.  If we leave
-	 * these set to "C" then message localization might not work well in the
-	 * postmaster.
+	 * Collation is handled by pg_locale.c, and the behavior is dependent on
+	 * the provider. strcoll(), etc., should not be called directly.
+	 */
+	init_locale("LC_COLLATE", LC_COLLATE, "C");
+
+	/*
+	 * In the postmaster, absorb the environment value for LC_CTYPE.
+	 * Individual backends will change it later to pg_database.datctype, but
+	 * the postmaster cannot do that.  If we leave it set to "C" then message
+	 * localization might not work well in the postmaster.
 	 */
-	init_locale("LC_COLLATE", LC_COLLATE, "");
 	init_locale("LC_CTYPE", LC_CTYPE, "");
 
 	/*
diff --git a/src/backend/optimizer/path/costsize.c b/src/backend/optimizer/path/costsize.c
index 3d44815ed5adf..344a3188317b1 100644
--- a/src/backend/optimizer/path/costsize.c
+++ b/src/backend/optimizer/path/costsize.c
@@ -2247,7 +2247,7 @@ append_nonpartial_cost(List *subpaths, int numpaths, int parallel_workers)
  *	  Determines and returns the cost of an Append node.
  */
 void
-cost_append(AppendPath *apath)
+cost_append(AppendPath *apath, PlannerInfo *root)
 {
 	ListCell   *l;
 
@@ -2309,26 +2309,52 @@ cost_append(AppendPath *apath)
 			foreach(l, apath->subpaths)
 			{
 				Path	   *subpath = (Path *) lfirst(l);
-				Path		sort_path;	/* dummy for result of cost_sort */
+				int			presorted_keys;
+				Path		sort_path;	/* dummy for result of
+										 * cost_sort/cost_incremental_sort */
 
-				if (!pathkeys_contained_in(pathkeys, subpath->pathkeys))
+				if (!pathkeys_count_contained_in(pathkeys, subpath->pathkeys,
+												 &presorted_keys))
 				{
 					/*
 					 * We'll need to insert a Sort node, so include costs for
-					 * that.  We can use the parent's LIMIT if any, since we
+					 * that.  We choose to use incremental sort if it is
+					 * enabled and there are presorted keys; otherwise we use
+					 * full sort.
+					 *
+					 * We can use the parent's LIMIT if any, since we
 					 * certainly won't pull more than that many tuples from
 					 * any child.
 					 */
-					cost_sort(&sort_path,
-							  NULL, /* doesn't currently need root */
-							  pathkeys,
-							  subpath->disabled_nodes,
-							  subpath->total_cost,
-							  subpath->rows,
-							  subpath->pathtarget->width,
-							  0.0,
-							  work_mem,
-							  apath->limit_tuples);
+					if (enable_incremental_sort && presorted_keys > 0)
+					{
+						cost_incremental_sort(&sort_path,
+											  root,
+											  pathkeys,
+											  presorted_keys,
+											  subpath->disabled_nodes,
+											  subpath->startup_cost,
+											  subpath->total_cost,
+											  subpath->rows,
+											  subpath->pathtarget->width,
+											  0.0,
+											  work_mem,
+											  apath->limit_tuples);
+					}
+					else
+					{
+						cost_sort(&sort_path,
+								  root,
+								  pathkeys,
+								  subpath->disabled_nodes,
+								  subpath->total_cost,
+								  subpath->rows,
+								  subpath->pathtarget->width,
+								  0.0,
+								  work_mem,
+								  apath->limit_tuples);
+					}
+
 					subpath = &sort_path;
 				}
 
@@ -2546,13 +2572,13 @@ cost_memoize_rescan(PlannerInfo *root, MemoizePath *mpath,
 	Cost		input_startup_cost = mpath->subpath->startup_cost;
 	Cost		input_total_cost = mpath->subpath->total_cost;
 	double		tuples = mpath->subpath->rows;
-	double		calls = mpath->calls;
+	Cardinality est_calls = mpath->est_calls;
 	int			width = mpath->subpath->pathtarget->width;
 
 	double		hash_mem_bytes;
 	double		est_entry_bytes;
-	double		est_cache_entries;
-	double		ndistinct;
+	Cardinality est_cache_entries;
+	Cardinality ndistinct;
 	double		evict_ratio;
 	double		hit_ratio;
 	Cost		startup_cost;
@@ -2578,7 +2604,7 @@ cost_memoize_rescan(PlannerInfo *root, MemoizePath *mpath,
 	est_cache_entries = floor(hash_mem_bytes / est_entry_bytes);
 
 	/* estimate on the distinct number of parameter values */
-	ndistinct = estimate_num_groups(root, mpath->param_exprs, calls, NULL,
+	ndistinct = estimate_num_groups(root, mpath->param_exprs, est_calls, NULL,
 									&estinfo);
 
 	/*
@@ -2590,7 +2616,10 @@ cost_memoize_rescan(PlannerInfo *root, MemoizePath *mpath,
 	 * certainly mean a MemoizePath will never survive add_path().
 	 */
 	if ((estinfo.flags & SELFLAG_USED_DEFAULT) != 0)
-		ndistinct = calls;
+		ndistinct = est_calls;
+
+	/* Remember the ndistinct estimate for EXPLAIN */
+	mpath->est_unique_keys = ndistinct;
 
 	/*
 	 * Since we've already estimated the maximum number of entries we can
@@ -2618,9 +2647,12 @@ cost_memoize_rescan(PlannerInfo *root, MemoizePath *mpath,
 	 * must look at how many scans are estimated in total for this node and
 	 * how many of those scans we expect to get a cache hit.
 	 */
-	hit_ratio = ((calls - ndistinct) / calls) *
+	hit_ratio = ((est_calls - ndistinct) / est_calls) *
 		(est_cache_entries / Max(ndistinct, est_cache_entries));
 
+	/* Remember the hit ratio estimate for EXPLAIN */
+	mpath->est_hit_ratio = hit_ratio;
+
 	Assert(hit_ratio >= 0 && hit_ratio <= 1.0);
 
 	/*
diff --git a/src/backend/optimizer/path/joinpath.c b/src/backend/optimizer/path/joinpath.c
index 7aa8f5d799cac..ebedc5574ca9c 100644
--- a/src/backend/optimizer/path/joinpath.c
+++ b/src/backend/optimizer/path/joinpath.c
@@ -154,13 +154,17 @@ add_paths_to_joinrel(PlannerInfo *root,
 	/*
 	 * See if the inner relation is provably unique for this outer rel.
 	 *
-	 * We have some special cases: for JOIN_SEMI and JOIN_ANTI, it doesn't
-	 * matter since the executor can make the equivalent optimization anyway;
-	 * we need not expend planner cycles on proofs.  For JOIN_UNIQUE_INNER, we
-	 * must be considering a semijoin whose inner side is not provably unique
-	 * (else reduce_unique_semijoins would've simplified it), so there's no
-	 * point in calling innerrel_is_unique.  However, if the LHS covers all of
-	 * the semijoin's min_lefthand, then it's appropriate to set inner_unique
+	 * We have some special cases: for JOIN_SEMI, it doesn't matter since the
+	 * executor can make the equivalent optimization anyway.  It also doesn't
+	 * help enable use of Memoize, since a semijoin with a provably unique
+	 * inner side should have been reduced to an inner join in that case.
+	 * Therefore, we need not expend planner cycles on proofs.  (For
+	 * JOIN_ANTI, although it doesn't help the executor for the same reason,
+	 * it can benefit Memoize paths.)  For JOIN_UNIQUE_INNER, we must be
+	 * considering a semijoin whose inner side is not provably unique (else
+	 * reduce_unique_semijoins would've simplified it), so there's no point in
+	 * calling innerrel_is_unique.  However, if the LHS covers all of the
+	 * semijoin's min_lefthand, then it's appropriate to set inner_unique
 	 * because the path produced by create_unique_path will be unique relative
 	 * to the LHS.  (If we have an LHS that's only part of the min_lefthand,
 	 * that is *not* true.)  For JOIN_UNIQUE_OUTER, pass JOIN_INNER to avoid
@@ -169,12 +173,6 @@ add_paths_to_joinrel(PlannerInfo *root,
 	switch (jointype)
 	{
 		case JOIN_SEMI:
-		case JOIN_ANTI:
-
-			/*
-			 * XXX it may be worth proving this to allow a Memoize to be
-			 * considered for Nested Loop Semi/Anti Joins.
-			 */
 			extra.inner_unique = false; /* well, unproven */
 			break;
 		case JOIN_UNIQUE_INNER:
@@ -715,16 +713,21 @@ get_memoize_path(PlannerInfo *root, RelOptInfo *innerrel,
 		return NULL;
 
 	/*
-	 * Currently we don't do this for SEMI and ANTI joins unless they're
-	 * marked as inner_unique.  This is because nested loop SEMI/ANTI joins
-	 * don't scan the inner node to completion, which will mean memoize cannot
-	 * mark the cache entry as complete.
-	 *
-	 * XXX Currently we don't attempt to mark SEMI/ANTI joins as inner_unique
-	 * = true.  Should we?  See add_paths_to_joinrel()
+	 * Currently we don't do this for SEMI and ANTI joins, because nested loop
+	 * SEMI/ANTI joins don't scan the inner node to completion, which means
+	 * memoize cannot mark the cache entry as complete.  Nor can we mark the
+	 * cache entry as complete after fetching the first inner tuple, because
+	 * if that tuple and the current outer tuple don't satisfy the join
+	 * clauses, a second inner tuple that satisfies the parameters would find
+	 * the cache entry already marked as complete.  The only exception is when
+	 * the inner relation is provably unique, as in that case, there won't be
+	 * a second matching tuple and we can safely mark the cache entry as
+	 * complete after fetching the first inner tuple.  Note that in such
+	 * cases, the SEMI join should have been reduced to an inner join by
+	 * reduce_unique_semijoins.
 	 */
-	if (!extra->inner_unique && (jointype == JOIN_SEMI ||
-								 jointype == JOIN_ANTI))
+	if ((jointype == JOIN_SEMI || jointype == JOIN_ANTI) &&
+		!extra->inner_unique)
 		return NULL;
 
 	/*
diff --git a/src/backend/optimizer/plan/createplan.c b/src/backend/optimizer/plan/createplan.c
index 0b61aef962c6d..bfefc7dbea106 100644
--- a/src/backend/optimizer/plan/createplan.c
+++ b/src/backend/optimizer/plan/createplan.c
@@ -284,7 +284,10 @@ static Material *make_material(Plan *lefttree);
 static Memoize *make_memoize(Plan *lefttree, Oid *hashoperators,
 							 Oid *collations, List *param_exprs,
 							 bool singlerow, bool binary_mode,
-							 uint32 est_entries, Bitmapset *keyparamids);
+							 uint32 est_entries, Bitmapset *keyparamids,
+							 Cardinality est_calls,
+							 Cardinality est_unique_keys,
+							 double est_hit_ratio);
 static WindowAgg *make_windowagg(List *tlist, WindowClause *wc,
 								 int partNumCols, AttrNumber *partColIdx, Oid *partOperators, Oid *partCollations,
 								 int ordNumCols, AttrNumber *ordColIdx, Oid *ordOperators, Oid *ordCollations,
@@ -1318,6 +1321,7 @@ create_append_plan(PlannerInfo *root, AppendPath *best_path, int flags)
 			Oid		   *sortOperators;
 			Oid		   *collations;
 			bool	   *nullsFirst;
+			int			presorted_keys;
 
 			/*
 			 * Compute sort column info, and adjust subplan's tlist as needed.
@@ -1353,14 +1357,38 @@ create_append_plan(PlannerInfo *root, AppendPath *best_path, int flags)
 						  numsortkeys * sizeof(bool)) == 0);
 
 			/* Now, insert a Sort node if subplan isn't sufficiently ordered */
-			if (!pathkeys_contained_in(pathkeys, subpath->pathkeys))
+			if (!pathkeys_count_contained_in(pathkeys, subpath->pathkeys,
+											 &presorted_keys))
 			{
-				Sort	   *sort = make_sort(subplan, numsortkeys,
+				Plan	   *sort_plan;
+
+				/*
+				 * We choose to use incremental sort if it is enabled and
+				 * there are presorted keys; otherwise we use full sort.
+				 */
+				if (enable_incremental_sort && presorted_keys > 0)
+				{
+					sort_plan = (Plan *)
+						make_incrementalsort(subplan, numsortkeys, presorted_keys,
 											 sortColIdx, sortOperators,
 											 collations, nullsFirst);
 
-				label_sort_with_costsize(root, sort, best_path->limit_tuples);
-				subplan = (Plan *) sort;
+					label_incrementalsort_with_costsize(root,
+														(IncrementalSort *) sort_plan,
+														pathkeys,
+														best_path->limit_tuples);
+				}
+				else
+				{
+					sort_plan = (Plan *) make_sort(subplan, numsortkeys,
+												   sortColIdx, sortOperators,
+												   collations, nullsFirst);
+
+					label_sort_with_costsize(root, (Sort *) sort_plan,
+											 best_path->limit_tuples);
+				}
+
+				subplan = sort_plan;
 			}
 		}
 
@@ -1491,6 +1519,7 @@ create_merge_append_plan(PlannerInfo *root, MergeAppendPath *best_path,
 		Oid		   *sortOperators;
 		Oid		   *collations;
 		bool	   *nullsFirst;
+		int			presorted_keys;
 
 		/* Build the child plan */
 		/* Must insist that all children return the same tlist */
@@ -1525,14 +1554,38 @@ create_merge_append_plan(PlannerInfo *root, MergeAppendPath *best_path,
 					  numsortkeys * sizeof(bool)) == 0);
 
 		/* Now, insert a Sort node if subplan isn't sufficiently ordered */
-		if (!pathkeys_contained_in(pathkeys, subpath->pathkeys))
+		if (!pathkeys_count_contained_in(pathkeys, subpath->pathkeys,
+										 &presorted_keys))
 		{
-			Sort	   *sort = make_sort(subplan, numsortkeys,
+			Plan	   *sort_plan;
+
+			/*
+			 * We choose to use incremental sort if it is enabled and there
+			 * are presorted keys; otherwise we use full sort.
+			 */
+			if (enable_incremental_sort && presorted_keys > 0)
+			{
+				sort_plan = (Plan *)
+					make_incrementalsort(subplan, numsortkeys, presorted_keys,
 										 sortColIdx, sortOperators,
 										 collations, nullsFirst);
 
-			label_sort_with_costsize(root, sort, best_path->limit_tuples);
-			subplan = (Plan *) sort;
+				label_incrementalsort_with_costsize(root,
+													(IncrementalSort *) sort_plan,
+													pathkeys,
+													best_path->limit_tuples);
+			}
+			else
+			{
+				sort_plan = (Plan *) make_sort(subplan, numsortkeys,
+											   sortColIdx, sortOperators,
+											   collations, nullsFirst);
+
+				label_sort_with_costsize(root, (Sort *) sort_plan,
+										 best_path->limit_tuples);
+			}
+
+			subplan = sort_plan;
 		}
 
 		subplans = lappend(subplans, subplan);
@@ -1703,7 +1756,8 @@ create_memoize_plan(PlannerInfo *root, MemoizePath *best_path, int flags)
 
 	plan = make_memoize(subplan, operators, collations, param_exprs,
 						best_path->singlerow, best_path->binary_mode,
-						best_path->est_entries, keyparamids);
+						best_path->est_entries, keyparamids, best_path->est_calls,
+						best_path->est_unique_keys, best_path->est_hit_ratio);
 
 	copy_generic_path_info(&plan->plan, (Path *) best_path);
 
@@ -6699,7 +6753,9 @@ materialize_finished_plan(Plan *subplan)
 static Memoize *
 make_memoize(Plan *lefttree, Oid *hashoperators, Oid *collations,
 			 List *param_exprs, bool singlerow, bool binary_mode,
-			 uint32 est_entries, Bitmapset *keyparamids)
+			 uint32 est_entries, Bitmapset *keyparamids,
+			 Cardinality est_calls, Cardinality est_unique_keys,
+			 double est_hit_ratio)
 {
 	Memoize    *node = makeNode(Memoize);
 	Plan	   *plan = &node->plan;
@@ -6717,6 +6773,9 @@ make_memoize(Plan *lefttree, Oid *hashoperators, Oid *collations,
 	node->binary_mode = binary_mode;
 	node->est_entries = est_entries;
 	node->keyparamids = keyparamids;
+	node->est_calls = est_calls;
+	node->est_unique_keys = est_unique_keys;
+	node->est_hit_ratio = est_hit_ratio;
 
 	return node;
 }
diff --git a/src/backend/optimizer/plan/initsplan.c b/src/backend/optimizer/plan/initsplan.c
index 01804b085b3ba..3e3fec8925291 100644
--- a/src/backend/optimizer/plan/initsplan.c
+++ b/src/backend/optimizer/plan/initsplan.c
@@ -3048,36 +3048,16 @@ add_base_clause_to_rel(PlannerInfo *root, Index relid,
  * expr_is_nonnullable
  *	  Check to see if the Expr cannot be NULL
  *
- * If the Expr is a simple Var that is defined NOT NULL and meanwhile is not
- * nulled by any outer joins, then we can know that it cannot be NULL.
+ * Currently we only support simple Vars.
  */
 static bool
 expr_is_nonnullable(PlannerInfo *root, Expr *expr)
 {
-	RelOptInfo *rel;
-	Var		   *var;
-
 	/* For now only check simple Vars */
 	if (!IsA(expr, Var))
 		return false;
 
-	var = (Var *) expr;
-
-	/* could the Var be nulled by any outer joins? */
-	if (!bms_is_empty(var->varnullingrels))
-		return false;
-
-	/* system columns cannot be NULL */
-	if (var->varattno < 0)
-		return true;
-
-	/* is the column defined NOT NULL? */
-	rel = find_base_rel(root, var->varno);
-	if (var->varattno > 0 &&
-		bms_is_member(var->varattno, rel->notnullattnums))
-		return true;
-
-	return false;
+	return var_is_nonnullable(root, (Var *) expr, true);
 }
 
 /*
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c
index 549aedcfa991a..d59d6e4c6a021 100644
--- a/src/backend/optimizer/plan/planner.c
+++ b/src/backend/optimizer/plan/planner.c
@@ -342,6 +342,7 @@ standard_planner(Query *parse, const char *query_string, int cursorOptions,
 	glob->transientPlan = false;
 	glob->dependsOnRole = false;
 	glob->partition_directory = NULL;
+	glob->rel_notnullatts_hash = NULL;
 
 	/*
 	 * Assess whether it's feasible to use parallel mode for this query. We
@@ -557,6 +558,7 @@ standard_planner(Query *parse, const char *query_string, int cursorOptions,
 
 	result->commandType = parse->commandType;
 	result->queryId = parse->queryId;
+	result->planOrigin = PLAN_STMT_STANDARD;
 	result->hasReturning = (parse->returningList != NIL);
 	result->hasModifyingCTE = parse->hasModifyingCTE;
 	result->canSetTag = parse->canSetTag;
@@ -720,6 +722,18 @@ subquery_planner(PlannerGlobal *glob, Query *parse, PlannerInfo *parent_root,
 	 */
 	transform_MERGE_to_join(parse);
 
+	/*
+	 * Scan the rangetable for relation RTEs and retrieve the necessary
+	 * catalog information for each relation.  Using this information, clear
+	 * the inh flag for any relation that has no children, collect not-null
+	 * attribute numbers for any relation that has column not-null
+	 * constraints, and expand virtual generated columns for any relation that
+	 * contains them.  Note that this step does not descend into sublinks and
+	 * subqueries; if we pull up any sublinks or subqueries below, their
+	 * relation RTEs are processed just before pulling them up.
+	 */
+	parse = root->parse = preprocess_relation_rtes(root);
+
 	/*
 	 * If the FROM clause is empty, replace it with a dummy RTE_RESULT RTE, so
 	 * that we don't need so many special cases to deal with that situation.
@@ -743,14 +757,6 @@ subquery_planner(PlannerGlobal *glob, Query *parse, PlannerInfo *parent_root,
 	 */
 	preprocess_function_rtes(root);
 
-	/*
-	 * Scan the rangetable for relations with virtual generated columns, and
-	 * replace all Var nodes in the query that reference these columns with
-	 * the generation expressions.  Recursion issues here are handled in the
-	 * same way as for SubLinks.
-	 */
-	parse = root->parse = expand_virtual_generated_columns(root);
-
 	/*
 	 * Check to see if any subqueries in the jointree can be merged into this
 	 * query.
@@ -787,23 +793,6 @@ subquery_planner(PlannerGlobal *glob, Query *parse, PlannerInfo *parent_root,
 
 		switch (rte->rtekind)
 		{
-			case RTE_RELATION:
-				if (rte->inh)
-				{
-					/*
-					 * Check to see if the relation actually has any children;
-					 * if not, clear the inh flag so we can treat it as a
-					 * plain base relation.
-					 *
-					 * Note: this could give a false-positive result, if the
-					 * rel once had children but no longer does.  We used to
-					 * be able to clear rte->inh later on when we discovered
-					 * that, but no more; we have to handle such cases as
-					 * full-fledged inheritance.
-					 */
-					rte->inh = has_subclass(rte->relid);
-				}
-				break;
 			case RTE_JOIN:
 				root->hasJoinRTEs = true;
 				if (IS_OUTER_JOIN(rte->jointype))
diff --git a/src/backend/optimizer/plan/subselect.c b/src/backend/optimizer/plan/subselect.c
index e7cb3fede6658..d71ed958e31b3 100644
--- a/src/backend/optimizer/plan/subselect.c
+++ b/src/backend/optimizer/plan/subselect.c
@@ -1454,6 +1454,7 @@ convert_EXISTS_sublink_to_join(PlannerInfo *root, SubLink *sublink,
 	Query	   *parse = root->parse;
 	Query	   *subselect = (Query *) sublink->subselect;
 	Node	   *whereClause;
+	PlannerInfo subroot;
 	int			rtoffset;
 	int			varno;
 	Relids		clause_varnos;
@@ -1515,6 +1516,35 @@ convert_EXISTS_sublink_to_join(PlannerInfo *root, SubLink *sublink,
 	if (contain_volatile_functions(whereClause))
 		return NULL;
 
+	/*
+	 * Scan the rangetable for relation RTEs and retrieve the necessary
+	 * catalog information for each relation.  Using this information, clear
+	 * the inh flag for any relation that has no children, collect not-null
+	 * attribute numbers for any relation that has column not-null
+	 * constraints, and expand virtual generated columns for any relation that
+	 * contains them.
+	 *
+	 * Note: we construct up an entirely dummy PlannerInfo for use here.  This
+	 * is fine because only the "glob" and "parse" links will be used in this
+	 * case.
+	 *
+	 * Note: we temporarily assign back the WHERE clause so that any virtual
+	 * generated column references within it can be expanded.  It should be
+	 * separated out again afterward.
+	 */
+	MemSet(&subroot, 0, sizeof(subroot));
+	subroot.type = T_PlannerInfo;
+	subroot.glob = root->glob;
+	subroot.parse = subselect;
+	subselect->jointree->quals = whereClause;
+	subselect = preprocess_relation_rtes(&subroot);
+
+	/*
+	 * Now separate out the WHERE clause again.
+	 */
+	whereClause = subselect->jointree->quals;
+	subselect->jointree->quals = NULL;
+
 	/*
 	 * The subquery must have a nonempty jointree, but we can make it so.
 	 */
@@ -1732,6 +1762,7 @@ convert_EXISTS_to_ANY(PlannerInfo *root, Query *subselect,
 					  Node **testexpr, List **paramIds)
 {
 	Node	   *whereClause;
+	PlannerInfo subroot;
 	List	   *leftargs,
 			   *rightargs,
 			   *opids,
@@ -1791,12 +1822,15 @@ convert_EXISTS_to_ANY(PlannerInfo *root, Query *subselect,
 	 * parent aliases were flattened already, and we're not going to pull any
 	 * child Vars (of any description) into the parent.
 	 *
-	 * Note: passing the parent's root to eval_const_expressions is
-	 * technically wrong, but we can get away with it since only the
-	 * boundParams (if any) are used, and those would be the same in a
-	 * subroot.
-	 */
-	whereClause = eval_const_expressions(root, whereClause);
+	 * Note: we construct up an entirely dummy PlannerInfo to pass to
+	 * eval_const_expressions.  This is fine because only the "glob" and
+	 * "parse" links are used by eval_const_expressions.
+	 */
+	MemSet(&subroot, 0, sizeof(subroot));
+	subroot.type = T_PlannerInfo;
+	subroot.glob = root->glob;
+	subroot.parse = subselect;
+	whereClause = eval_const_expressions(&subroot, whereClause);
 	whereClause = (Node *) canonicalize_qual((Expr *) whereClause, false);
 	whereClause = (Node *) make_ands_implicit((Expr *) whereClause);
 
diff --git a/src/backend/optimizer/prep/prepjointree.c b/src/backend/optimizer/prep/prepjointree.c
index 87dc6f56b576f..35e8d3c183b47 100644
--- a/src/backend/optimizer/prep/prepjointree.c
+++ b/src/backend/optimizer/prep/prepjointree.c
@@ -4,10 +4,10 @@
  *	  Planner preprocessing for subqueries and join tree manipulation.
  *
  * NOTE: the intended sequence for invoking these operations is
+ *		preprocess_relation_rtes
  *		replace_empty_jointree
  *		pull_up_sublinks
  *		preprocess_function_rtes
- *		expand_virtual_generated_columns
  *		pull_up_subqueries
  *		flatten_simple_union_all
  *		do expression preprocessing (including flattening JOIN alias vars)
@@ -36,6 +36,7 @@
 #include "optimizer/clauses.h"
 #include "optimizer/optimizer.h"
 #include "optimizer/placeholder.h"
+#include "optimizer/plancat.h"
 #include "optimizer/prep.h"
 #include "optimizer/subselect.h"
 #include "optimizer/tlist.h"
@@ -102,6 +103,9 @@ typedef struct reduce_outer_joins_partial_state
 	Relids		unreduced_side; /* relids in its still-nullable side */
 } reduce_outer_joins_partial_state;
 
+static Query *expand_virtual_generated_columns(PlannerInfo *root, Query *parse,
+											   RangeTblEntry *rte, int rt_index,
+											   Relation relation);
 static Node *pull_up_sublinks_jointree_recurse(PlannerInfo *root, Node *jtnode,
 											   Relids *relids);
 static Node *pull_up_sublinks_qual_recurse(PlannerInfo *root, Node *node,
@@ -392,6 +396,181 @@ transform_MERGE_to_join(Query *parse)
 		parse->mergeJoinCondition = NULL;	/* join condition not needed */
 }
 
+/*
+ * preprocess_relation_rtes
+ *		Do the preprocessing work for any relation RTEs in the FROM clause.
+ *
+ * This scans the rangetable for relation RTEs and retrieves the necessary
+ * catalog information for each relation.  Using this information, it clears
+ * the inh flag for any relation that has no children, collects not-null
+ * attribute numbers for any relation that has column not-null constraints, and
+ * expands virtual generated columns for any relation that contains them.
+ *
+ * Note that expanding virtual generated columns may cause the query tree to
+ * have new copies of rangetable entries.  Therefore, we have to use list_nth
+ * instead of foreach when iterating over the query's rangetable.
+ *
+ * Returns a modified copy of the query tree, if any relations with virtual
+ * generated columns are present.
+ */
+Query *
+preprocess_relation_rtes(PlannerInfo *root)
+{
+	Query	   *parse = root->parse;
+	int			rtable_size;
+	int			rt_index;
+
+	rtable_size = list_length(parse->rtable);
+
+	for (rt_index = 0; rt_index < rtable_size; rt_index++)
+	{
+		RangeTblEntry *rte = rt_fetch(rt_index + 1, parse->rtable);
+		Relation	relation;
+
+		/* We only care about relation RTEs. */
+		if (rte->rtekind != RTE_RELATION)
+			continue;
+
+		/*
+		 * We need not lock the relation since it was already locked by the
+		 * rewriter.
+		 */
+		relation = table_open(rte->relid, NoLock);
+
+		/*
+		 * Check to see if the relation actually has any children; if not,
+		 * clear the inh flag so we can treat it as a plain base relation.
+		 *
+		 * Note: this could give a false-positive result, if the rel once had
+		 * children but no longer does.  We used to be able to clear rte->inh
+		 * later on when we discovered that, but no more; we have to handle
+		 * such cases as full-fledged inheritance.
+		 */
+		if (rte->inh)
+			rte->inh = relation->rd_rel->relhassubclass;
+
+		/*
+		 * Check to see if the relation has any column not-null constraints;
+		 * if so, retrieve the constraint information and store it in a
+		 * relation OID based hash table.
+		 */
+		get_relation_notnullatts(root, relation);
+
+		/*
+		 * Check to see if the relation has any virtual generated columns; if
+		 * so, replace all Var nodes in the query that reference these columns
+		 * with the generation expressions.
+		 */
+		parse = expand_virtual_generated_columns(root, parse,
+												 rte, rt_index + 1,
+												 relation);
+
+		table_close(relation, NoLock);
+	}
+
+	return parse;
+}
+
+/*
+ * expand_virtual_generated_columns
+ *		Expand virtual generated columns for the given relation.
+ *
+ * This checks whether the given relation has any virtual generated columns,
+ * and if so, replaces all Var nodes in the query that reference those columns
+ * with their generation expressions.
+ *
+ * Returns a modified copy of the query tree if the relation contains virtual
+ * generated columns.
+ */
+static Query *
+expand_virtual_generated_columns(PlannerInfo *root, Query *parse,
+								 RangeTblEntry *rte, int rt_index,
+								 Relation relation)
+{
+	TupleDesc	tupdesc;
+
+	/* Only normal relations can have virtual generated columns */
+	Assert(rte->rtekind == RTE_RELATION);
+
+	tupdesc = RelationGetDescr(relation);
+	if (tupdesc->constr && tupdesc->constr->has_generated_virtual)
+	{
+		List	   *tlist = NIL;
+		pullup_replace_vars_context rvcontext;
+
+		for (int i = 0; i < tupdesc->natts; i++)
+		{
+			Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
+			TargetEntry *tle;
+
+			if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL)
+			{
+				Node	   *defexpr;
+
+				defexpr = build_generation_expression(relation, i + 1);
+				ChangeVarNodes(defexpr, 1, rt_index, 0);
+
+				tle = makeTargetEntry((Expr *) defexpr, i + 1, 0, false);
+				tlist = lappend(tlist, tle);
+			}
+			else
+			{
+				Var		   *var;
+
+				var = makeVar(rt_index,
+							  i + 1,
+							  attr->atttypid,
+							  attr->atttypmod,
+							  attr->attcollation,
+							  0);
+
+				tle = makeTargetEntry((Expr *) var, i + 1, 0, false);
+				tlist = lappend(tlist, tle);
+			}
+		}
+
+		Assert(list_length(tlist) > 0);
+		Assert(!rte->lateral);
+
+		/*
+		 * The relation's targetlist items are now in the appropriate form to
+		 * insert into the query, except that we may need to wrap them in
+		 * PlaceHolderVars.  Set up required context data for
+		 * pullup_replace_vars.
+		 */
+		rvcontext.root = root;
+		rvcontext.targetlist = tlist;
+		rvcontext.target_rte = rte;
+		rvcontext.result_relation = parse->resultRelation;
+		/* won't need these values */
+		rvcontext.relids = NULL;
+		rvcontext.nullinfo = NULL;
+		/* pass NULL for outer_hasSubLinks */
+		rvcontext.outer_hasSubLinks = NULL;
+		rvcontext.varno = rt_index;
+		/* this flag will be set below, if needed */
+		rvcontext.wrap_option = REPLACE_WRAP_NONE;
+		/* initialize cache array with indexes 0 .. length(tlist) */
+		rvcontext.rv_cache = palloc0((list_length(tlist) + 1) *
+									 sizeof(Node *));
+
+		/*
+		 * If the query uses grouping sets, we need a PlaceHolderVar for each
+		 * expression of the relation's targetlist items.  (See comments in
+		 * pull_up_simple_subquery().)
+		 */
+		if (parse->groupingSets)
+			rvcontext.wrap_option = REPLACE_WRAP_ALL;
+
+		/*
+		 * Apply pullup variable replacement throughout the query tree.
+		 */
+		parse = (Query *) pullup_replace_vars((Node *) parse, &rvcontext);
+	}
+
+	return parse;
+}
+
 /*
  * replace_empty_jointree
  *		If the Query's jointree is empty, replace it with a dummy RTE_RESULT
@@ -949,128 +1128,6 @@ preprocess_function_rtes(PlannerInfo *root)
 	}
 }
 
-/*
- * expand_virtual_generated_columns
- *		Expand all virtual generated column references in a query.
- *
- * This scans the rangetable for relations with virtual generated columns, and
- * replaces all Var nodes in the query that reference these columns with the
- * generation expressions.  Note that we do not descend into subqueries; that
- * is taken care of when the subqueries are planned.
- *
- * This has to be done after we have pulled up any SubLinks within the query's
- * quals; otherwise any virtual generated column references within the SubLinks
- * that should be transformed into joins wouldn't get expanded.
- *
- * Returns a modified copy of the query tree, if any relations with virtual
- * generated columns are present.
- */
-Query *
-expand_virtual_generated_columns(PlannerInfo *root)
-{
-	Query	   *parse = root->parse;
-	int			rt_index;
-	ListCell   *lc;
-
-	rt_index = 0;
-	foreach(lc, parse->rtable)
-	{
-		RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc);
-		Relation	rel;
-		TupleDesc	tupdesc;
-
-		++rt_index;
-
-		/*
-		 * Only normal relations can have virtual generated columns.
-		 */
-		if (rte->rtekind != RTE_RELATION)
-			continue;
-
-		rel = table_open(rte->relid, NoLock);
-
-		tupdesc = RelationGetDescr(rel);
-		if (tupdesc->constr && tupdesc->constr->has_generated_virtual)
-		{
-			List	   *tlist = NIL;
-			pullup_replace_vars_context rvcontext;
-
-			for (int i = 0; i < tupdesc->natts; i++)
-			{
-				Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
-				TargetEntry *tle;
-
-				if (attr->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL)
-				{
-					Node	   *defexpr;
-
-					defexpr = build_generation_expression(rel, i + 1);
-					ChangeVarNodes(defexpr, 1, rt_index, 0);
-
-					tle = makeTargetEntry((Expr *) defexpr, i + 1, 0, false);
-					tlist = lappend(tlist, tle);
-				}
-				else
-				{
-					Var		   *var;
-
-					var = makeVar(rt_index,
-								  i + 1,
-								  attr->atttypid,
-								  attr->atttypmod,
-								  attr->attcollation,
-								  0);
-
-					tle = makeTargetEntry((Expr *) var, i + 1, 0, false);
-					tlist = lappend(tlist, tle);
-				}
-			}
-
-			Assert(list_length(tlist) > 0);
-			Assert(!rte->lateral);
-
-			/*
-			 * The relation's targetlist items are now in the appropriate form
-			 * to insert into the query, except that we may need to wrap them
-			 * in PlaceHolderVars.  Set up required context data for
-			 * pullup_replace_vars.
-			 */
-			rvcontext.root = root;
-			rvcontext.targetlist = tlist;
-			rvcontext.target_rte = rte;
-			rvcontext.result_relation = parse->resultRelation;
-			/* won't need these values */
-			rvcontext.relids = NULL;
-			rvcontext.nullinfo = NULL;
-			/* pass NULL for outer_hasSubLinks */
-			rvcontext.outer_hasSubLinks = NULL;
-			rvcontext.varno = rt_index;
-			/* this flag will be set below, if needed */
-			rvcontext.wrap_option = REPLACE_WRAP_NONE;
-			/* initialize cache array with indexes 0 .. length(tlist) */
-			rvcontext.rv_cache = palloc0((list_length(tlist) + 1) *
-										 sizeof(Node *));
-
-			/*
-			 * If the query uses grouping sets, we need a PlaceHolderVar for
-			 * each expression of the relation's targetlist items.  (See
-			 * comments in pull_up_simple_subquery().)
-			 */
-			if (parse->groupingSets)
-				rvcontext.wrap_option = REPLACE_WRAP_ALL;
-
-			/*
-			 * Apply pullup variable replacement throughout the query tree.
-			 */
-			parse = (Query *) pullup_replace_vars((Node *) parse, &rvcontext);
-		}
-
-		table_close(rel, NoLock);
-	}
-
-	return parse;
-}
-
 /*
  * pull_up_subqueries
  *		Look for subqueries in the rangetable that can be pulled up into
@@ -1333,6 +1390,16 @@ pull_up_simple_subquery(PlannerInfo *root, Node *jtnode, RangeTblEntry *rte,
 	/* No CTEs to worry about */
 	Assert(subquery->cteList == NIL);
 
+	/*
+	 * Scan the rangetable for relation RTEs and retrieve the necessary
+	 * catalog information for each relation.  Using this information, clear
+	 * the inh flag for any relation that has no children, collect not-null
+	 * attribute numbers for any relation that has column not-null
+	 * constraints, and expand virtual generated columns for any relation that
+	 * contains them.
+	 */
+	subquery = subroot->parse = preprocess_relation_rtes(subroot);
+
 	/*
 	 * If the FROM clause is empty, replace it with a dummy RTE_RESULT RTE, so
 	 * that we don't need so many special cases to deal with that situation.
@@ -1352,13 +1419,6 @@ pull_up_simple_subquery(PlannerInfo *root, Node *jtnode, RangeTblEntry *rte,
 	 */
 	preprocess_function_rtes(subroot);
 
-	/*
-	 * Scan the rangetable for relations with virtual generated columns, and
-	 * replace all Var nodes in the query that reference these columns with
-	 * the generation expressions.
-	 */
-	subquery = subroot->parse = expand_virtual_generated_columns(subroot);
-
 	/*
 	 * Recursively pull up the subquery's subqueries, so that
 	 * pull_up_subqueries' processing is complete for its jointree and
diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c
index 26a3e0500866c..6f0b338d2cdf1 100644
--- a/src/backend/optimizer/util/clauses.c
+++ b/src/backend/optimizer/util/clauses.c
@@ -20,6 +20,7 @@
 #include "postgres.h"
 
 #include "access/htup_details.h"
+#include "catalog/pg_class.h"
 #include "catalog/pg_language.h"
 #include "catalog/pg_operator.h"
 #include "catalog/pg_proc.h"
@@ -36,6 +37,7 @@
 #include "optimizer/clauses.h"
 #include "optimizer/cost.h"
 #include "optimizer/optimizer.h"
+#include "optimizer/pathnode.h"
 #include "optimizer/plancat.h"
 #include "optimizer/planmain.h"
 #include "parser/analyze.h"
@@ -43,6 +45,7 @@
 #include "parser/parse_collate.h"
 #include "parser/parse_func.h"
 #include "parser/parse_oper.h"
+#include "parser/parsetree.h"
 #include "rewrite/rewriteHandler.h"
 #include "rewrite/rewriteManip.h"
 #include "tcop/tcopprot.h"
@@ -2242,7 +2245,8 @@ rowtype_field_matches(Oid rowtypeid, int fieldnum,
  * only operators and functions that are reasonable to try to execute.
  *
  * NOTE: "root" can be passed as NULL if the caller never wants to do any
- * Param substitutions nor receive info about inlined functions.
+ * Param substitutions nor receive info about inlined functions nor reduce
+ * NullTest for Vars to constant true or constant false.
  *
  * NOTE: the planner assumes that this will always flatten nested AND and
  * OR clauses into N-argument form.  See comments in prepqual.c.
@@ -3333,6 +3337,13 @@ eval_const_expressions_mutator(Node *node,
 												  -1,
 												  coalesceexpr->coalescecollid);
 
+				/*
+				 * If there's exactly one surviving argument, we no longer
+				 * need COALESCE at all: the result is that argument
+				 */
+				if (list_length(newargs) == 1)
+					return (Node *) linitial(newargs);
+
 				newcoalesce = makeNode(CoalesceExpr);
 				newcoalesce->coalescetype = coalesceexpr->coalescetype;
 				newcoalesce->coalescecollid = coalesceexpr->coalescecollid;
@@ -3537,6 +3548,31 @@ eval_const_expressions_mutator(Node *node,
 
 					return makeBoolConst(result, false);
 				}
+				if (!ntest->argisrow && arg && IsA(arg, Var) && context->root)
+				{
+					Var		   *varg = (Var *) arg;
+					bool		result;
+
+					if (var_is_nonnullable(context->root, varg, false))
+					{
+						switch (ntest->nulltesttype)
+						{
+							case IS_NULL:
+								result = false;
+								break;
+							case IS_NOT_NULL:
+								result = true;
+								break;
+							default:
+								elog(ERROR, "unrecognized nulltesttype: %d",
+									 (int) ntest->nulltesttype);
+								result = false; /* keep compiler quiet */
+								break;
+						}
+
+						return makeBoolConst(result, false);
+					}
+				}
 
 				newntest = makeNode(NullTest);
 				newntest->arg = (Expr *) arg;
@@ -4155,6 +4191,67 @@ simplify_function(Oid funcid, Oid result_type, int32 result_typmod,
 	return newexpr;
 }
 
+/*
+ * var_is_nonnullable: check to see if the Var cannot be NULL
+ *
+ * If the Var is defined NOT NULL and meanwhile is not nulled by any outer
+ * joins or grouping sets, then we can know that it cannot be NULL.
+ *
+ * use_rel_info indicates whether the corresponding RelOptInfo is available for
+ * use.
+ */
+bool
+var_is_nonnullable(PlannerInfo *root, Var *var, bool use_rel_info)
+{
+	Relids		notnullattnums = NULL;
+
+	Assert(IsA(var, Var));
+
+	/* skip upper-level Vars */
+	if (var->varlevelsup != 0)
+		return false;
+
+	/* could the Var be nulled by any outer joins or grouping sets? */
+	if (!bms_is_empty(var->varnullingrels))
+		return false;
+
+	/* system columns cannot be NULL */
+	if (var->varattno < 0)
+		return true;
+
+	/*
+	 * Check if the Var is defined as NOT NULL.  We retrieve the column NOT
+	 * NULL constraint information from the corresponding RelOptInfo if it is
+	 * available; otherwise, we search the hash table for this information.
+	 */
+	if (use_rel_info)
+	{
+		RelOptInfo *rel = find_base_rel(root, var->varno);
+
+		notnullattnums = rel->notnullattnums;
+	}
+	else
+	{
+		RangeTblEntry *rte = planner_rt_fetch(var->varno, root);
+
+		/*
+		 * We must skip inheritance parent tables, as some child tables may
+		 * have a NOT NULL constraint for a column while others may not.  This
+		 * cannot happen with partitioned tables, though.
+		 */
+		if (rte->inh && rte->relkind != RELKIND_PARTITIONED_TABLE)
+			return false;
+
+		notnullattnums = find_relation_notnullatts(root, rte->relid);
+	}
+
+	if (var->varattno > 0 &&
+		bms_is_member(var->varattno, notnullattnums))
+		return true;
+
+	return false;
+}
+
 /*
  * expand_function_arguments: convert named-notation args to positional args
  * and/or insert default args, as needed
diff --git a/src/backend/optimizer/util/inherit.c b/src/backend/optimizer/util/inherit.c
index 17e51cd75d744..30d158069e332 100644
--- a/src/backend/optimizer/util/inherit.c
+++ b/src/backend/optimizer/util/inherit.c
@@ -466,8 +466,7 @@ expand_single_inheritance_child(PlannerInfo *root, RangeTblEntry *parentrte,
 								Index *childRTindex_p)
 {
 	Query	   *parse = root->parse;
-	Oid			parentOID PG_USED_FOR_ASSERTS_ONLY =
-		RelationGetRelid(parentrel);
+	Oid			parentOID = RelationGetRelid(parentrel);
 	Oid			childOID = RelationGetRelid(childrel);
 	RangeTblEntry *childrte;
 	Index		childRTindex;
@@ -513,6 +512,13 @@ expand_single_inheritance_child(PlannerInfo *root, RangeTblEntry *parentrte,
 	*childrte_p = childrte;
 	*childRTindex_p = childRTindex;
 
+	/*
+	 * Retrieve column not-null constraint information for the child relation
+	 * if its relation OID is different from the parent's.
+	 */
+	if (childOID != parentOID)
+		get_relation_notnullatts(root, childrel);
+
 	/*
 	 * Build an AppendRelInfo struct for each parent/child pair.
 	 */
diff --git a/src/backend/optimizer/util/pathnode.c b/src/backend/optimizer/util/pathnode.c
index e0192d4a491d2..a4c5867cdcb84 100644
--- a/src/backend/optimizer/util/pathnode.c
+++ b/src/backend/optimizer/util/pathnode.c
@@ -1404,12 +1404,12 @@ create_append_path(PlannerInfo *root,
 			pathnode->path.total_cost = child->total_cost;
 		}
 		else
-			cost_append(pathnode);
+			cost_append(pathnode, root);
 		/* Must do this last, else cost_append complains */
 		pathnode->path.pathkeys = child->pathkeys;
 	}
 	else
-		cost_append(pathnode);
+		cost_append(pathnode, root);
 
 	/* If the caller provided a row estimate, override the computed value. */
 	if (rows >= 0)
@@ -1515,6 +1515,9 @@ create_merge_append_path(PlannerInfo *root,
 	foreach(l, subpaths)
 	{
 		Path	   *subpath = (Path *) lfirst(l);
+		int			presorted_keys;
+		Path		sort_path;	/* dummy for result of
+								 * cost_sort/cost_incremental_sort */
 
 		/* All child paths should be unparameterized */
 		Assert(bms_is_empty(PATH_REQ_OUTER(subpath)));
@@ -1523,32 +1526,52 @@ create_merge_append_path(PlannerInfo *root,
 		pathnode->path.parallel_safe = pathnode->path.parallel_safe &&
 			subpath->parallel_safe;
 
-		if (pathkeys_contained_in(pathkeys, subpath->pathkeys))
+		if (!pathkeys_count_contained_in(pathkeys, subpath->pathkeys,
+										 &presorted_keys))
 		{
-			/* Subpath is adequately ordered, we won't need to sort it */
-			input_disabled_nodes += subpath->disabled_nodes;
-			input_startup_cost += subpath->startup_cost;
-			input_total_cost += subpath->total_cost;
-		}
-		else
-		{
-			/* We'll need to insert a Sort node, so include cost for that */
-			Path		sort_path;	/* dummy for result of cost_sort */
+			/*
+			 * We'll need to insert a Sort node, so include costs for that. We
+			 * choose to use incremental sort if it is enabled and there are
+			 * presorted keys; otherwise we use full sort.
+			 *
+			 * We can use the parent's LIMIT if any, since we certainly won't
+			 * pull more than that many tuples from any child.
+			 */
+			if (enable_incremental_sort && presorted_keys > 0)
+			{
+				cost_incremental_sort(&sort_path,
+									  root,
+									  pathkeys,
+									  presorted_keys,
+									  subpath->disabled_nodes,
+									  subpath->startup_cost,
+									  subpath->total_cost,
+									  subpath->rows,
+									  subpath->pathtarget->width,
+									  0.0,
+									  work_mem,
+									  pathnode->limit_tuples);
+			}
+			else
+			{
+				cost_sort(&sort_path,
+						  root,
+						  pathkeys,
+						  subpath->disabled_nodes,
+						  subpath->total_cost,
+						  subpath->rows,
+						  subpath->pathtarget->width,
+						  0.0,
+						  work_mem,
+						  pathnode->limit_tuples);
+			}
 
-			cost_sort(&sort_path,
-					  root,
-					  pathkeys,
-					  subpath->disabled_nodes,
-					  subpath->total_cost,
-					  subpath->rows,
-					  subpath->pathtarget->width,
-					  0.0,
-					  work_mem,
-					  pathnode->limit_tuples);
-			input_disabled_nodes += sort_path.disabled_nodes;
-			input_startup_cost += sort_path.startup_cost;
-			input_total_cost += sort_path.total_cost;
+			subpath = &sort_path;
 		}
+
+		input_disabled_nodes += subpath->disabled_nodes;
+		input_startup_cost += subpath->startup_cost;
+		input_total_cost += subpath->total_cost;
 	}
 
 	/*
@@ -1666,7 +1689,7 @@ create_material_path(RelOptInfo *rel, Path *subpath)
 MemoizePath *
 create_memoize_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath,
 					List *param_exprs, List *hash_operators,
-					bool singlerow, bool binary_mode, double calls)
+					bool singlerow, bool binary_mode, Cardinality est_calls)
 {
 	MemoizePath *pathnode = makeNode(MemoizePath);
 
@@ -1687,7 +1710,6 @@ create_memoize_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath,
 	pathnode->param_exprs = param_exprs;
 	pathnode->singlerow = singlerow;
 	pathnode->binary_mode = binary_mode;
-	pathnode->calls = clamp_row_est(calls);
 
 	/*
 	 * For now we set est_entries to 0.  cost_memoize_rescan() does all the
@@ -1697,6 +1719,12 @@ create_memoize_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath,
 	 */
 	pathnode->est_entries = 0;
 
+	pathnode->est_calls = clamp_row_est(est_calls);
+
+	/* These will also be set later in cost_memoize_rescan() */
+	pathnode->est_unique_keys = 0.0;
+	pathnode->est_hit_ratio = 0.0;
+
 	/* we should not generate this path type when enable_memoize=false */
 	Assert(enable_memoize);
 	pathnode->path.disabled_nodes = subpath->disabled_nodes;
@@ -4236,7 +4264,7 @@ reparameterize_path(PlannerInfo *root, Path *path,
 													mpath->hash_operators,
 													mpath->singlerow,
 													mpath->binary_mode,
-													mpath->calls);
+													mpath->est_calls);
 			}
 		default:
 			break;
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index 59233b647302d..c6a58afc5e506 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -59,6 +59,12 @@ int			constraint_exclusion = CONSTRAINT_EXCLUSION_PARTITION;
 /* Hook for plugins to get control in get_relation_info() */
 get_relation_info_hook_type get_relation_info_hook = NULL;
 
+typedef struct NotnullHashEntry
+{
+	Oid			relid;			/* OID of the relation */
+	Relids		notnullattnums; /* attnums of NOT NULL columns */
+} NotnullHashEntry;
+
 
 static void get_relation_foreign_keys(PlannerInfo *root, RelOptInfo *rel,
 									  Relation relation, bool inhparent);
@@ -172,27 +178,7 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 	 * RangeTblEntry does get populated.
 	 */
 	if (!inhparent || relation->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
-	{
-		for (int i = 0; i < relation->rd_att->natts; i++)
-		{
-			CompactAttribute *attr = TupleDescCompactAttr(relation->rd_att, i);
-
-			Assert(attr->attnullability != ATTNULLABLE_UNKNOWN);
-
-			if (attr->attnullability == ATTNULLABLE_VALID)
-			{
-				rel->notnullattnums = bms_add_member(rel->notnullattnums,
-													 i + 1);
-
-				/*
-				 * Per RemoveAttributeById(), dropped columns will have their
-				 * attnotnull unset, so we needn't check for dropped columns
-				 * in the above condition.
-				 */
-				Assert(!attr->attisdropped);
-			}
-		}
-	}
+		rel->notnullattnums = find_relation_notnullatts(root, relationObjectId);
 
 	/*
 	 * Estimate relation size --- unless it's an inheritance parent, in which
@@ -683,6 +669,105 @@ get_relation_foreign_keys(PlannerInfo *root, RelOptInfo *rel,
 	}
 }
 
+/*
+ * get_relation_notnullatts -
+ *	  Retrieves column not-null constraint information for a given relation.
+ *
+ * We do this while we have the relcache entry open, and store the column
+ * not-null constraint information in a hash table based on the relation OID.
+ */
+void
+get_relation_notnullatts(PlannerInfo *root, Relation relation)
+{
+	Oid			relid = RelationGetRelid(relation);
+	NotnullHashEntry *hentry;
+	bool		found;
+	Relids		notnullattnums = NULL;
+
+	/* bail out if the relation has no not-null constraints */
+	if (relation->rd_att->constr == NULL ||
+		!relation->rd_att->constr->has_not_null)
+		return;
+
+	/* create the hash table if it hasn't been created yet */
+	if (root->glob->rel_notnullatts_hash == NULL)
+	{
+		HTAB	   *hashtab;
+		HASHCTL		hash_ctl;
+
+		hash_ctl.keysize = sizeof(Oid);
+		hash_ctl.entrysize = sizeof(NotnullHashEntry);
+		hash_ctl.hcxt = CurrentMemoryContext;
+
+		hashtab = hash_create("Relation NOT NULL attnums",
+							  64L,	/* arbitrary initial size */
+							  &hash_ctl,
+							  HASH_ELEM | HASH_BLOBS | HASH_CONTEXT);
+
+		root->glob->rel_notnullatts_hash = hashtab;
+	}
+
+	/*
+	 * Create a hash entry for this relation OID, if we don't have one
+	 * already.
+	 */
+	hentry = (NotnullHashEntry *) hash_search(root->glob->rel_notnullatts_hash,
+											  &relid,
+											  HASH_ENTER,
+											  &found);
+
+	/* bail out if a hash entry already exists for this relation OID */
+	if (found)
+		return;
+
+	/* collect the column not-null constraint information for this relation */
+	for (int i = 0; i < relation->rd_att->natts; i++)
+	{
+		CompactAttribute *attr = TupleDescCompactAttr(relation->rd_att, i);
+
+		Assert(attr->attnullability != ATTNULLABLE_UNKNOWN);
+
+		if (attr->attnullability == ATTNULLABLE_VALID)
+		{
+			notnullattnums = bms_add_member(notnullattnums, i + 1);
+
+			/*
+			 * Per RemoveAttributeById(), dropped columns will have their
+			 * attnotnull unset, so we needn't check for dropped columns in
+			 * the above condition.
+			 */
+			Assert(!attr->attisdropped);
+		}
+	}
+
+	/* ... and initialize the new hash entry */
+	hentry->notnullattnums = notnullattnums;
+}
+
+/*
+ * find_relation_notnullatts -
+ *	  Searches the hash table and returns the column not-null constraint
+ *	  information for a given relation.
+ */
+Relids
+find_relation_notnullatts(PlannerInfo *root, Oid relid)
+{
+	NotnullHashEntry *hentry;
+	bool		found;
+
+	if (root->glob->rel_notnullatts_hash == NULL)
+		return NULL;
+
+	hentry = (NotnullHashEntry *) hash_search(root->glob->rel_notnullatts_hash,
+											  &relid,
+											  HASH_FIND,
+											  &found);
+	if (!found)
+		return NULL;
+
+	return hentry->notnullattnums;
+}
+
 /*
  * infer_arbiter_indexes -
  *	  Determine the unique indexes used to arbitrate speculative insertion.
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 50f53159d5819..db43034b9db57 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -318,6 +318,11 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 %type <list>		opt_qualified_name
 %type <boolean>		opt_concurrently
 %type <dbehavior>	opt_drop_behavior
+%type <list>		opt_utility_option_list
+%type <list>		utility_option_list
+%type <defelt>		utility_option_elem
+%type <str>			utility_option_name
+%type <node>		utility_option_arg
 
 %type <node>	alter_column_default opclass_item opclass_drop alter_using
 %type <ival>	add_drop opt_asc_desc opt_nulls_order
@@ -338,10 +343,6 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 				create_extension_opt_item alter_extension_opt_item
 
 %type <ival>	opt_lock lock_type cast_context
-%type <str>		utility_option_name
-%type <defelt>	utility_option_elem
-%type <list>	utility_option_list
-%type <node>	utility_option_arg
 %type <defelt>	drop_option
 %type <boolean>	opt_or_replace opt_no
 				opt_grant_grant_option
@@ -556,7 +557,6 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
 %type <list>	generic_option_list alter_generic_option_list
 
 %type <ival>	reindex_target_relation reindex_target_all
-%type <list>	opt_reindex_option_list
 
 %type <node>	copy_generic_opt_arg copy_generic_opt_arg_list_item
 %type <defelt>	copy_generic_opt_elem
@@ -1141,6 +1141,41 @@ opt_drop_behavior:
 			| /* EMPTY */					{ $$ = DROP_RESTRICT; /* default */ }
 		;
 
+opt_utility_option_list:
+			'(' utility_option_list ')'		{ $$ = $2; }
+			| /* EMPTY */					{ $$ = NULL; }
+		;
+
+utility_option_list:
+			utility_option_elem
+				{
+					$$ = list_make1($1);
+				}
+			| utility_option_list ',' utility_option_elem
+				{
+					$$ = lappend($1, $3);
+				}
+		;
+
+utility_option_elem:
+			utility_option_name utility_option_arg
+				{
+					$$ = makeDefElem($1, $2, @1);
+				}
+		;
+
+utility_option_name:
+			NonReservedWord					{ $$ = $1; }
+			| analyze_keyword				{ $$ = "analyze"; }
+			| FORMAT_LA						{ $$ = "format"; }
+		;
+
+utility_option_arg:
+			opt_boolean_or_string			{ $$ = (Node *) makeString($1); }
+			| NumericOnly					{ $$ = (Node *) $1; }
+			| /* EMPTY */					{ $$ = NULL; }
+		;
+
 /*****************************************************************************
  *
  * CALL statement
@@ -2028,11 +2063,12 @@ constraints_set_mode:
  * Checkpoint statement
  */
 CheckPointStmt:
-			CHECKPOINT
+			CHECKPOINT opt_utility_option_list
 				{
 					CheckPointStmt *n = makeNode(CheckPointStmt);
 
 					$$ = (Node *) n;
+					n->options = $2;
 				}
 		;
 
@@ -2668,6 +2704,12 @@ alter_table_cmd:
 						c->alterDeferrability = true;
 					if ($4 & CAS_NO_INHERIT)
 						c->alterInheritability = true;
+					/* handle unsupported case with specific error message */
+					if ($4 & CAS_NOT_VALID)
+						ereport(ERROR,
+								errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+								errmsg("constraints cannot be altered to be NOT VALID"),
+								parser_errposition(@4));
 					processCASbits($4, @4, "FOREIGN KEY",
 									&c->deferrable,
 									&c->initdeferred,
@@ -6035,6 +6077,26 @@ CreateTrigStmt:
 			EXECUTE FUNCTION_or_PROCEDURE func_name '(' TriggerFuncArgs ')'
 				{
 					CreateTrigStmt *n = makeNode(CreateTrigStmt);
+					bool		dummy;
+
+					if (($11 & CAS_NOT_VALID) != 0)
+						ereport(ERROR,
+								errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+								errmsg("constraint triggers cannot be marked %s",
+									   "NOT VALID"),
+								parser_errposition(@11));
+					if (($11 & CAS_NO_INHERIT) != 0)
+						ereport(ERROR,
+								errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+								errmsg("constraint triggers cannot be marked %s",
+									   "NO INHERIT"),
+								parser_errposition(@11));
+					if (($11 & CAS_NOT_ENFORCED) != 0)
+						ereport(ERROR,
+								errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+								errmsg("constraint triggers cannot be marked %s",
+									   "NOT ENFORCED"),
+								parser_errposition(@11));
 
 					n->replace = $2;
 					if (n->replace) /* not supported, see CreateTrigger */
@@ -6054,7 +6116,7 @@ CreateTrigStmt:
 					n->whenClause = $15;
 					n->transitionRels = NIL;
 					processCASbits($11, @11, "TRIGGER",
-								   &n->deferrable, &n->initdeferred, NULL,
+								   &n->deferrable, &n->initdeferred, &dummy,
 								   NULL, NULL, yyscanner);
 					n->constrrel = $10;
 					$$ = (Node *) n;
@@ -7477,6 +7539,8 @@ fetch_args:	cursor_name
 					n->portalname = $1;
 					n->direction = FETCH_FORWARD;
 					n->howMany = 1;
+					n->location = -1;
+					n->direction_keyword = FETCH_KEYWORD_NONE;
 					$$ = (Node *) n;
 				}
 			| from_in cursor_name
@@ -7486,6 +7550,19 @@ fetch_args:	cursor_name
 					n->portalname = $2;
 					n->direction = FETCH_FORWARD;
 					n->howMany = 1;
+					n->location = -1;
+					n->direction_keyword = FETCH_KEYWORD_NONE;
+					$$ = (Node *) n;
+				}
+			| SignedIconst opt_from_in cursor_name
+				{
+					FetchStmt *n = makeNode(FetchStmt);
+
+					n->portalname = $3;
+					n->direction = FETCH_FORWARD;
+					n->howMany = $1;
+					n->location = @1;
+					n->direction_keyword = FETCH_KEYWORD_NONE;
 					$$ = (Node *) n;
 				}
 			| NEXT opt_from_in cursor_name
@@ -7495,6 +7572,8 @@ fetch_args:	cursor_name
 					n->portalname = $3;
 					n->direction = FETCH_FORWARD;
 					n->howMany = 1;
+					n->location = -1;
+					n->direction_keyword = FETCH_KEYWORD_NEXT;
 					$$ = (Node *) n;
 				}
 			| PRIOR opt_from_in cursor_name
@@ -7504,6 +7583,8 @@ fetch_args:	cursor_name
 					n->portalname = $3;
 					n->direction = FETCH_BACKWARD;
 					n->howMany = 1;
+					n->location = -1;
+					n->direction_keyword = FETCH_KEYWORD_PRIOR;
 					$$ = (Node *) n;
 				}
 			| FIRST_P opt_from_in cursor_name
@@ -7513,6 +7594,8 @@ fetch_args:	cursor_name
 					n->portalname = $3;
 					n->direction = FETCH_ABSOLUTE;
 					n->howMany = 1;
+					n->location = -1;
+					n->direction_keyword = FETCH_KEYWORD_FIRST;
 					$$ = (Node *) n;
 				}
 			| LAST_P opt_from_in cursor_name
@@ -7522,6 +7605,8 @@ fetch_args:	cursor_name
 					n->portalname = $3;
 					n->direction = FETCH_ABSOLUTE;
 					n->howMany = -1;
+					n->location = -1;
+					n->direction_keyword = FETCH_KEYWORD_LAST;
 					$$ = (Node *) n;
 				}
 			| ABSOLUTE_P SignedIconst opt_from_in cursor_name
@@ -7531,6 +7616,8 @@ fetch_args:	cursor_name
 					n->portalname = $4;
 					n->direction = FETCH_ABSOLUTE;
 					n->howMany = $2;
+					n->location = @2;
+					n->direction_keyword = FETCH_KEYWORD_ABSOLUTE;
 					$$ = (Node *) n;
 				}
 			| RELATIVE_P SignedIconst opt_from_in cursor_name
@@ -7540,15 +7627,8 @@ fetch_args:	cursor_name
 					n->portalname = $4;
 					n->direction = FETCH_RELATIVE;
 					n->howMany = $2;
-					$$ = (Node *) n;
-				}
-			| SignedIconst opt_from_in cursor_name
-				{
-					FetchStmt *n = makeNode(FetchStmt);
-
-					n->portalname = $3;
-					n->direction = FETCH_FORWARD;
-					n->howMany = $1;
+					n->location = @2;
+					n->direction_keyword = FETCH_KEYWORD_RELATIVE;
 					$$ = (Node *) n;
 				}
 			| ALL opt_from_in cursor_name
@@ -7558,6 +7638,8 @@ fetch_args:	cursor_name
 					n->portalname = $3;
 					n->direction = FETCH_FORWARD;
 					n->howMany = FETCH_ALL;
+					n->location = -1;
+					n->direction_keyword = FETCH_KEYWORD_ALL;
 					$$ = (Node *) n;
 				}
 			| FORWARD opt_from_in cursor_name
@@ -7567,6 +7649,8 @@ fetch_args:	cursor_name
 					n->portalname = $3;
 					n->direction = FETCH_FORWARD;
 					n->howMany = 1;
+					n->location = -1;
+					n->direction_keyword = FETCH_KEYWORD_FORWARD;
 					$$ = (Node *) n;
 				}
 			| FORWARD SignedIconst opt_from_in cursor_name
@@ -7576,6 +7660,8 @@ fetch_args:	cursor_name
 					n->portalname = $4;
 					n->direction = FETCH_FORWARD;
 					n->howMany = $2;
+					n->location = @2;
+					n->direction_keyword = FETCH_KEYWORD_FORWARD;
 					$$ = (Node *) n;
 				}
 			| FORWARD ALL opt_from_in cursor_name
@@ -7585,6 +7671,8 @@ fetch_args:	cursor_name
 					n->portalname = $4;
 					n->direction = FETCH_FORWARD;
 					n->howMany = FETCH_ALL;
+					n->location = -1;
+					n->direction_keyword = FETCH_KEYWORD_FORWARD_ALL;
 					$$ = (Node *) n;
 				}
 			| BACKWARD opt_from_in cursor_name
@@ -7594,6 +7682,8 @@ fetch_args:	cursor_name
 					n->portalname = $3;
 					n->direction = FETCH_BACKWARD;
 					n->howMany = 1;
+					n->location = -1;
+					n->direction_keyword = FETCH_KEYWORD_BACKWARD;
 					$$ = (Node *) n;
 				}
 			| BACKWARD SignedIconst opt_from_in cursor_name
@@ -7603,6 +7693,8 @@ fetch_args:	cursor_name
 					n->portalname = $4;
 					n->direction = FETCH_BACKWARD;
 					n->howMany = $2;
+					n->location = @2;
+					n->direction_keyword = FETCH_KEYWORD_BACKWARD;
 					$$ = (Node *) n;
 				}
 			| BACKWARD ALL opt_from_in cursor_name
@@ -7612,6 +7704,8 @@ fetch_args:	cursor_name
 					n->portalname = $4;
 					n->direction = FETCH_BACKWARD;
 					n->howMany = FETCH_ALL;
+					n->location = -1;
+					n->direction_keyword = FETCH_KEYWORD_BACKWARD_ALL;
 					$$ = (Node *) n;
 				}
 		;
@@ -9289,7 +9383,7 @@ DropTransformStmt: DROP TRANSFORM opt_if_exists FOR Typename LANGUAGE name opt_d
  *****************************************************************************/
 
 ReindexStmt:
-			REINDEX opt_reindex_option_list reindex_target_relation opt_concurrently qualified_name
+			REINDEX opt_utility_option_list reindex_target_relation opt_concurrently qualified_name
 				{
 					ReindexStmt *n = makeNode(ReindexStmt);
 
@@ -9302,7 +9396,7 @@ ReindexStmt:
 											makeDefElem("concurrently", NULL, @4));
 					$$ = (Node *) n;
 				}
-			| REINDEX opt_reindex_option_list SCHEMA opt_concurrently name
+			| REINDEX opt_utility_option_list SCHEMA opt_concurrently name
 				{
 					ReindexStmt *n = makeNode(ReindexStmt);
 
@@ -9315,7 +9409,7 @@ ReindexStmt:
 											makeDefElem("concurrently", NULL, @4));
 					$$ = (Node *) n;
 				}
-			| REINDEX opt_reindex_option_list reindex_target_all opt_concurrently opt_single_name
+			| REINDEX opt_utility_option_list reindex_target_all opt_concurrently opt_single_name
 				{
 					ReindexStmt *n = makeNode(ReindexStmt);
 
@@ -9337,10 +9431,6 @@ reindex_target_all:
 			SYSTEM_P				{ $$ = REINDEX_OBJECT_SYSTEM; }
 			| DATABASE				{ $$ = REINDEX_OBJECT_DATABASE; }
 		;
-opt_reindex_option_list:
-			'(' utility_option_list ')'				{ $$ = $2; }
-			| /* EMPTY */							{ $$ = NULL; }
-		;
 
 /*****************************************************************************
  *
@@ -11627,7 +11717,7 @@ AlterDomainStmt:
 				{
 					AlterDomainStmt *n = makeNode(AlterDomainStmt);
 
-					n->subtype = 'T';
+					n->subtype = AD_AlterDefault;
 					n->typeName = $3;
 					n->def = $4;
 					$$ = (Node *) n;
@@ -11637,7 +11727,7 @@ AlterDomainStmt:
 				{
 					AlterDomainStmt *n = makeNode(AlterDomainStmt);
 
-					n->subtype = 'N';
+					n->subtype = AD_DropNotNull;
 					n->typeName = $3;
 					$$ = (Node *) n;
 				}
@@ -11646,7 +11736,7 @@ AlterDomainStmt:
 				{
 					AlterDomainStmt *n = makeNode(AlterDomainStmt);
 
-					n->subtype = 'O';
+					n->subtype = AD_SetNotNull;
 					n->typeName = $3;
 					$$ = (Node *) n;
 				}
@@ -11655,7 +11745,7 @@ AlterDomainStmt:
 				{
 					AlterDomainStmt *n = makeNode(AlterDomainStmt);
 
-					n->subtype = 'C';
+					n->subtype = AD_AddConstraint;
 					n->typeName = $3;
 					n->def = $5;
 					$$ = (Node *) n;
@@ -11665,7 +11755,7 @@ AlterDomainStmt:
 				{
 					AlterDomainStmt *n = makeNode(AlterDomainStmt);
 
-					n->subtype = 'X';
+					n->subtype = AD_DropConstraint;
 					n->typeName = $3;
 					n->name = $6;
 					n->behavior = $7;
@@ -11677,7 +11767,7 @@ AlterDomainStmt:
 				{
 					AlterDomainStmt *n = makeNode(AlterDomainStmt);
 
-					n->subtype = 'X';
+					n->subtype = AD_DropConstraint;
 					n->typeName = $3;
 					n->name = $8;
 					n->behavior = $9;
@@ -11689,7 +11779,7 @@ AlterDomainStmt:
 				{
 					AlterDomainStmt *n = makeNode(AlterDomainStmt);
 
-					n->subtype = 'V';
+					n->subtype = AD_ValidateConstraint;
 					n->typeName = $3;
 					n->name = $6;
 					$$ = (Node *) n;
@@ -11838,13 +11928,13 @@ ClusterStmt:
 					n->params = $3;
 					$$ = (Node *) n;
 				}
-			| CLUSTER '(' utility_option_list ')'
+			| CLUSTER opt_utility_option_list
 				{
 					ClusterStmt *n = makeNode(ClusterStmt);
 
 					n->relation = NULL;
 					n->indexname = NULL;
-					n->params = $3;
+					n->params = $2;
 					$$ = (Node *) n;
 				}
 			/* unparenthesized VERBOSE kept for pre-14 compatibility */
@@ -11854,21 +11944,18 @@ ClusterStmt:
 
 					n->relation = $3;
 					n->indexname = $4;
-					n->params = NIL;
 					if ($2)
-						n->params = lappend(n->params, makeDefElem("verbose", NULL, @2));
+						n->params = list_make1(makeDefElem("verbose", NULL, @2));
 					$$ = (Node *) n;
 				}
 			/* unparenthesized VERBOSE kept for pre-17 compatibility */
-			| CLUSTER opt_verbose
+			| CLUSTER VERBOSE
 				{
 					ClusterStmt *n = makeNode(ClusterStmt);
 
 					n->relation = NULL;
 					n->indexname = NULL;
-					n->params = NIL;
-					if ($2)
-						n->params = lappend(n->params, makeDefElem("verbose", NULL, @2));
+					n->params = list_make1(makeDefElem("verbose", NULL, @2));
 					$$ = (Node *) n;
 				}
 			/* kept for pre-8.3 compatibility */
@@ -11878,9 +11965,8 @@ ClusterStmt:
 
 					n->relation = $5;
 					n->indexname = $3;
-					n->params = NIL;
 					if ($2)
-						n->params = lappend(n->params, makeDefElem("verbose", NULL, @2));
+						n->params = list_make1(makeDefElem("verbose", NULL, @2));
 					$$ = (Node *) n;
 				}
 		;
@@ -11931,64 +12017,31 @@ VacuumStmt: VACUUM opt_full opt_freeze opt_verbose opt_analyze opt_vacuum_relati
 				}
 		;
 
-AnalyzeStmt: analyze_keyword opt_verbose opt_vacuum_relation_list
+AnalyzeStmt: analyze_keyword opt_utility_option_list opt_vacuum_relation_list
 				{
 					VacuumStmt *n = makeNode(VacuumStmt);
 
-					n->options = NIL;
-					if ($2)
-						n->options = lappend(n->options,
-											 makeDefElem("verbose", NULL, @2));
+					n->options = $2;
 					n->rels = $3;
 					n->is_vacuumcmd = false;
 					$$ = (Node *) n;
 				}
-			| analyze_keyword '(' utility_option_list ')' opt_vacuum_relation_list
+			| analyze_keyword VERBOSE opt_vacuum_relation_list
 				{
 					VacuumStmt *n = makeNode(VacuumStmt);
 
-					n->options = $3;
-					n->rels = $5;
+					n->options = list_make1(makeDefElem("verbose", NULL, @2));
+					n->rels = $3;
 					n->is_vacuumcmd = false;
 					$$ = (Node *) n;
 				}
 		;
 
-utility_option_list:
-			utility_option_elem
-				{
-					$$ = list_make1($1);
-				}
-			| utility_option_list ',' utility_option_elem
-				{
-					$$ = lappend($1, $3);
-				}
-		;
-
 analyze_keyword:
 			ANALYZE
 			| ANALYSE /* British */
 		;
 
-utility_option_elem:
-			utility_option_name utility_option_arg
-				{
-					$$ = makeDefElem($1, $2, @1);
-				}
-		;
-
-utility_option_name:
-			NonReservedWord							{ $$ = $1; }
-			| analyze_keyword						{ $$ = "analyze"; }
-			| FORMAT_LA								{ $$ = "format"; }
-		;
-
-utility_option_arg:
-			opt_boolean_or_string					{ $$ = (Node *) makeString($1); }
-			| NumericOnly							{ $$ = (Node *) $1; }
-			| /* EMPTY */							{ $$ = NULL; }
-		;
-
 opt_analyze:
 			analyze_keyword							{ $$ = true; }
 			| /*EMPTY*/								{ $$ = false; }
diff --git a/src/backend/partitioning/partbounds.c b/src/backend/partitioning/partbounds.c
index 4bdc2941efb21..822cf4ec451a4 100644
--- a/src/backend/partitioning/partbounds.c
+++ b/src/backend/partitioning/partbounds.c
@@ -1007,9 +1007,6 @@ partition_bounds_copy(PartitionBoundInfo src,
 	int			ndatums;
 	int			nindexes;
 	int			partnatts;
-	bool		hash_part;
-	int			natts;
-	Datum	   *boundDatums;
 
 	dest = (PartitionBoundInfo) palloc(sizeof(PartitionBoundInfoData));
 
@@ -1023,7 +1020,7 @@ partition_bounds_copy(PartitionBoundInfo src,
 
 	dest->datums = (Datum **) palloc(sizeof(Datum *) * ndatums);
 
-	if (src->kind != NULL)
+	if (src->kind != NULL && ndatums > 0)
 	{
 		PartitionRangeDatumKind *boundKinds;
 
@@ -1058,36 +1055,40 @@ partition_bounds_copy(PartitionBoundInfo src,
 	 * For hash partitioning, datums array will have two elements - modulus
 	 * and remainder.
 	 */
-	hash_part = (key->strategy == PARTITION_STRATEGY_HASH);
-	natts = hash_part ? 2 : partnatts;
-	boundDatums = palloc(ndatums * natts * sizeof(Datum));
-
-	for (i = 0; i < ndatums; i++)
+	if (ndatums > 0)
 	{
-		int			j;
-
-		dest->datums[i] = &boundDatums[i * natts];
+		bool		hash_part = (key->strategy == PARTITION_STRATEGY_HASH);
+		int			natts = hash_part ? 2 : partnatts;
+		Datum	   *boundDatums = palloc(ndatums * natts * sizeof(Datum));
 
-		for (j = 0; j < natts; j++)
+		for (i = 0; i < ndatums; i++)
 		{
-			bool		byval;
-			int			typlen;
+			int			j;
 
-			if (hash_part)
-			{
-				typlen = sizeof(int32); /* Always int4 */
-				byval = true;	/* int4 is pass-by-value */
-			}
-			else
+			dest->datums[i] = &boundDatums[i * natts];
+
+			for (j = 0; j < natts; j++)
 			{
-				byval = key->parttypbyval[j];
-				typlen = key->parttyplen[j];
-			}
+				if (dest->kind == NULL ||
+					dest->kind[i][j] == PARTITION_RANGE_DATUM_VALUE)
+				{
+					bool		byval;
+					int			typlen;
 
-			if (dest->kind == NULL ||
-				dest->kind[i][j] == PARTITION_RANGE_DATUM_VALUE)
-				dest->datums[i][j] = datumCopy(src->datums[i][j],
-											   byval, typlen);
+					if (hash_part)
+					{
+						typlen = sizeof(int32); /* Always int4 */
+						byval = true;	/* int4 is pass-by-value */
+					}
+					else
+					{
+						byval = key->parttypbyval[j];
+						typlen = key->parttyplen[j];
+					}
+					dest->datums[i][j] = datumCopy(src->datums[i][j],
+												   byval, typlen);
+				}
+			}
 		}
 	}
 
diff --git a/src/backend/postmaster/autovacuum.c b/src/backend/postmaster/autovacuum.c
index 451fb90a610a7..ff96b36d71025 100644
--- a/src/backend/postmaster/autovacuum.c
+++ b/src/backend/postmaster/autovacuum.c
@@ -310,6 +310,16 @@ static AutoVacuumShmemStruct *AutoVacuumShmem;
 static dlist_head DatabaseList = DLIST_STATIC_INIT(DatabaseList);
 static MemoryContext DatabaseListCxt = NULL;
 
+/*
+ * Dummy pointer to persuade Valgrind that we've not leaked the array of
+ * avl_dbase structs.  Make it global to ensure the compiler doesn't
+ * optimize it away.
+ */
+#ifdef USE_VALGRIND
+extern avl_dbase *avl_dbase_array;
+avl_dbase  *avl_dbase_array;
+#endif
+
 /* Pointer to my own WorkerInfo, valid on each worker */
 static WorkerInfo MyWorkerInfo = NULL;
 
@@ -562,10 +572,10 @@ AutoVacLauncherMain(const void *startup_data, size_t startup_data_len)
 
 	/*
 	 * Create the initial database list.  The invariant we want this list to
-	 * keep is that it's ordered by decreasing next_time.  As soon as an entry
-	 * is updated to a higher time, it will be moved to the front (which is
-	 * correct because the only operation is to add autovacuum_naptime to the
-	 * entry, and time always increases).
+	 * keep is that it's ordered by decreasing next_worker.  As soon as an
+	 * entry is updated to a higher time, it will be moved to the front (which
+	 * is correct because the only operation is to add autovacuum_naptime to
+	 * the entry, and time always increases).
 	 */
 	rebuild_database_list(InvalidOid);
 
@@ -1020,6 +1030,10 @@ rebuild_database_list(Oid newdb)
 
 		/* put all the hash elements into an array */
 		dbary = palloc(nelems * sizeof(avl_dbase));
+		/* keep Valgrind quiet */
+#ifdef USE_VALGRIND
+		avl_dbase_array = dbary;
+#endif
 
 		i = 0;
 		hash_seq_init(&seq, dbhash);
@@ -2565,8 +2579,18 @@ do_autovacuum(void)
 
 	/*
 	 * We leak table_toast_map here (among other things), but since we're
-	 * going away soon, it's not a problem.
+	 * going away soon, it's not a problem normally.  But when using Valgrind,
+	 * release some stuff to reduce complaints about leaked storage.
 	 */
+#ifdef USE_VALGRIND
+	hash_destroy(table_toast_map);
+	FreeTupleDesc(pg_class_desc);
+	if (bstrategy)
+		pfree(bstrategy);
+#endif
+
+	/* Run the rest in xact context, mainly to avoid Valgrind leak warnings */
+	MemoryContextSwitchTo(TopTransactionContext);
 
 	/*
 	 * Update pg_database.datfrozenxid, and truncate pg_xact if possible. We
@@ -3190,7 +3214,7 @@ autovacuum_do_vac_analyze(autovac_table *tab, BufferAccessStrategy bstrategy)
 	rel_list = list_make1(rel);
 	MemoryContextSwitchTo(old_context);
 
-	vacuum(rel_list, &tab->at_params, bstrategy, vac_context, true);
+	vacuum(rel_list, tab->at_params, bstrategy, vac_context, true);
 
 	MemoryContextDelete(vac_context);
 }
diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c
index 116ddf7b835f1..1ad65c237c34e 100644
--- a/src/backend/postmaster/bgworker.c
+++ b/src/backend/postmaster/bgworker.c
@@ -613,6 +613,7 @@ ResetBackgroundWorkerCrashTimes(void)
 			 * resetting.
 			 */
 			rw->rw_crashed_at = 0;
+			rw->rw_pid = 0;
 
 			/*
 			 * If there was anyone waiting for it, they're history.
diff --git a/src/backend/postmaster/checkpointer.c b/src/backend/postmaster/checkpointer.c
index fda91ffd1ce2d..8490148a47d52 100644
--- a/src/backend/postmaster/checkpointer.c
+++ b/src/backend/postmaster/checkpointer.c
@@ -42,6 +42,8 @@
 #include "access/xlog.h"
 #include "access/xlog_internal.h"
 #include "access/xlogrecovery.h"
+#include "catalog/pg_authid.h"
+#include "commands/defrem.h"
 #include "libpq/pqsignal.h"
 #include "miscadmin.h"
 #include "pgstat.h"
@@ -61,6 +63,7 @@
 #include "storage/shmem.h"
 #include "storage/smgr.h"
 #include "storage/spin.h"
+#include "utils/acl.h"
 #include "utils/guc.h"
 #include "utils/memutils.h"
 #include "utils/resowner.h"
@@ -127,6 +130,13 @@ typedef struct
 
 	int			num_requests;	/* current # of requests */
 	int			max_requests;	/* allocated array size */
+
+	int			head;			/* Index of the first request in the ring
+								 * buffer */
+	int			tail;			/* Index of the last request in the ring
+								 * buffer */
+
+	/* The ring buffer of pending checkpointer requests */
 	CheckpointerRequest requests[FLEXIBLE_ARRAY_MEMBER];
 } CheckpointerShmemStruct;
 
@@ -135,6 +145,12 @@ static CheckpointerShmemStruct *CheckpointerShmem;
 /* interval for calling AbsorbSyncRequests in CheckpointWriteDelay */
 #define WRITES_PER_ABSORB		1000
 
+/* Maximum number of checkpointer requests to process in one batch */
+#define CKPT_REQ_BATCH_SIZE 10000
+
+/* Max number of requests the checkpointer request queue can hold */
+#define MAX_CHECKPOINT_REQUESTS 10000000
+
 /*
  * GUC parameters
  */
@@ -161,7 +177,7 @@ static pg_time_t last_xlog_switch_time;
 static void ProcessCheckpointerInterrupts(void);
 static void CheckArchiveTimeout(void);
 static bool IsCheckpointOnSchedule(double progress);
-static bool ImmediateCheckpointRequested(void);
+static bool FastCheckpointRequested(void);
 static bool CompactCheckpointerRequestQueue(void);
 static void UpdateSharedMemoryConfig(void);
 
@@ -734,12 +750,12 @@ CheckArchiveTimeout(void)
 }
 
 /*
- * Returns true if an immediate checkpoint request is pending.  (Note that
- * this does not check the *current* checkpoint's IMMEDIATE flag, but whether
- * there is one pending behind it.)
+ * Returns true if a fast checkpoint request is pending.  (Note that this does
+ * not check the *current* checkpoint's FAST flag, but whether there is one
+ * pending behind it.)
  */
 static bool
-ImmediateCheckpointRequested(void)
+FastCheckpointRequested(void)
 {
 	volatile CheckpointerShmemStruct *cps = CheckpointerShmem;
 
@@ -747,7 +763,7 @@ ImmediateCheckpointRequested(void)
 	 * We don't need to acquire the ckpt_lck in this case because we're only
 	 * looking at a single flag bit.
 	 */
-	if (cps->ckpt_flags & CHECKPOINT_IMMEDIATE)
+	if (cps->ckpt_flags & CHECKPOINT_FAST)
 		return true;
 	return false;
 }
@@ -760,7 +776,7 @@ ImmediateCheckpointRequested(void)
  * checkpoint_completion_target.
  *
  * The checkpoint request flags should be passed in; currently the only one
- * examined is CHECKPOINT_IMMEDIATE, which disables delays between writes.
+ * examined is CHECKPOINT_FAST, which disables delays between writes.
  *
  * 'progress' is an estimate of how much of the work has been done, as a
  * fraction between 0.0 meaning none, and 1.0 meaning all done.
@@ -778,10 +794,10 @@ CheckpointWriteDelay(int flags, double progress)
 	 * Perform the usual duties and take a nap, unless we're behind schedule,
 	 * in which case we just try to catch up as quickly as possible.
 	 */
-	if (!(flags & CHECKPOINT_IMMEDIATE) &&
+	if (!(flags & CHECKPOINT_FAST) &&
 		!ShutdownXLOGPending &&
 		!ShutdownRequestPending &&
-		!ImmediateCheckpointRequested() &&
+		!FastCheckpointRequested() &&
 		IsCheckpointOnSchedule(progress))
 	{
 		if (ConfigReloadPending)
@@ -970,12 +986,63 @@ CheckpointerShmemInit(void)
 		 */
 		MemSet(CheckpointerShmem, 0, size);
 		SpinLockInit(&CheckpointerShmem->ckpt_lck);
-		CheckpointerShmem->max_requests = NBuffers;
+		CheckpointerShmem->max_requests = Min(NBuffers, MAX_CHECKPOINT_REQUESTS);
+		CheckpointerShmem->head = CheckpointerShmem->tail = 0;
 		ConditionVariableInit(&CheckpointerShmem->start_cv);
 		ConditionVariableInit(&CheckpointerShmem->done_cv);
 	}
 }
 
+/*
+ * ExecCheckpoint
+ *		Primary entry point for manual CHECKPOINT commands
+ *
+ * This is mainly a wrapper for RequestCheckpoint().
+ */
+void
+ExecCheckpoint(ParseState *pstate, CheckPointStmt *stmt)
+{
+	bool		fast = true;
+	bool		unlogged = false;
+
+	foreach_ptr(DefElem, opt, stmt->options)
+	{
+		if (strcmp(opt->defname, "mode") == 0)
+		{
+			char	   *mode = defGetString(opt);
+
+			if (strcmp(mode, "spread") == 0)
+				fast = false;
+			else if (strcmp(mode, "fast") != 0)
+				ereport(ERROR,
+						(errcode(ERRCODE_SYNTAX_ERROR),
+						 errmsg("unrecognized MODE option \"%s\"", mode),
+						 parser_errposition(pstate, opt->location)));
+		}
+		else if (strcmp(opt->defname, "flush_unlogged") == 0)
+			unlogged = defGetBoolean(opt);
+		else
+			ereport(ERROR,
+					(errcode(ERRCODE_SYNTAX_ERROR),
+					 errmsg("unrecognized CHECKPOINT option \"%s\"", opt->defname),
+					 parser_errposition(pstate, opt->location)));
+	}
+
+	if (!has_privs_of_role(GetUserId(), ROLE_PG_CHECKPOINT))
+		ereport(ERROR,
+				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+		/* translator: %s is name of an SQL command (e.g., CHECKPOINT) */
+				 errmsg("permission denied to execute %s command",
+						"CHECKPOINT"),
+				 errdetail("Only roles with privileges of the \"%s\" role may execute this command.",
+						   "pg_checkpoint")));
+
+	RequestCheckpoint(CHECKPOINT_WAIT |
+					  (fast ? CHECKPOINT_FAST : 0) |
+					  (unlogged ? CHECKPOINT_FLUSH_UNLOGGED : 0) |
+					  (RecoveryInProgress() ? 0 : CHECKPOINT_FORCE));
+}
+
 /*
  * RequestCheckpoint
  *		Called in backend processes to request a checkpoint
@@ -983,11 +1050,11 @@ CheckpointerShmemInit(void)
  * flags is a bitwise OR of the following:
  *	CHECKPOINT_IS_SHUTDOWN: checkpoint is for database shutdown.
  *	CHECKPOINT_END_OF_RECOVERY: checkpoint is for end of WAL recovery.
- *	CHECKPOINT_IMMEDIATE: finish the checkpoint ASAP,
+ *	CHECKPOINT_FAST: finish the checkpoint ASAP,
  *		ignoring checkpoint_completion_target parameter.
  *	CHECKPOINT_FORCE: force a checkpoint even if no XLOG activity has occurred
  *		since the last one (implied by CHECKPOINT_IS_SHUTDOWN or
- *		CHECKPOINT_END_OF_RECOVERY).
+ *		CHECKPOINT_END_OF_RECOVERY, and the CHECKPOINT command).
  *	CHECKPOINT_WAIT: wait for completion before returning (otherwise,
  *		just signal checkpointer to do it, and return).
  *	CHECKPOINT_CAUSE_XLOG: checkpoint is requested due to xlog filling.
@@ -1009,7 +1076,7 @@ RequestCheckpoint(int flags)
 		 * There's no point in doing slow checkpoints in a standalone backend,
 		 * because there's no other backends the checkpoint could disrupt.
 		 */
-		CreateCheckPoint(flags | CHECKPOINT_IMMEDIATE);
+		CreateCheckPoint(flags | CHECKPOINT_FAST);
 
 		/* Free all smgr objects, as CheckpointerMain() normally would. */
 		smgrdestroyall();
@@ -1148,6 +1215,7 @@ ForwardSyncRequest(const FileTag *ftag, SyncRequestType type)
 {
 	CheckpointerRequest *request;
 	bool		too_full;
+	int			insert_pos;
 
 	if (!IsUnderPostmaster)
 		return false;			/* probably shouldn't even get here */
@@ -1171,10 +1239,14 @@ ForwardSyncRequest(const FileTag *ftag, SyncRequestType type)
 	}
 
 	/* OK, insert request */
-	request = &CheckpointerShmem->requests[CheckpointerShmem->num_requests++];
+	insert_pos = CheckpointerShmem->tail;
+	request = &CheckpointerShmem->requests[insert_pos];
 	request->ftag = *ftag;
 	request->type = type;
 
+	CheckpointerShmem->tail = (CheckpointerShmem->tail + 1) % CheckpointerShmem->max_requests;
+	CheckpointerShmem->num_requests++;
+
 	/* If queue is more than half full, nudge the checkpointer to empty it */
 	too_full = (CheckpointerShmem->num_requests >=
 				CheckpointerShmem->max_requests / 2);
@@ -1216,12 +1288,16 @@ CompactCheckpointerRequestQueue(void)
 	struct CheckpointerSlotMapping
 	{
 		CheckpointerRequest request;
-		int			slot;
+		int			ring_idx;
 	};
 
-	int			n,
-				preserve_count;
+	int			n;
 	int			num_skipped = 0;
+	int			head;
+	int			max_requests;
+	int			num_requests;
+	int			read_idx,
+				write_idx;
 	HASHCTL		ctl;
 	HTAB	   *htab;
 	bool	   *skip_slot;
@@ -1233,8 +1309,13 @@ CompactCheckpointerRequestQueue(void)
 	if (CritSectionCount > 0)
 		return false;
 
+	max_requests = CheckpointerShmem->max_requests;
+	num_requests = CheckpointerShmem->num_requests;
+
 	/* Initialize skip_slot array */
-	skip_slot = palloc0(sizeof(bool) * CheckpointerShmem->num_requests);
+	skip_slot = palloc0(sizeof(bool) * max_requests);
+
+	head = CheckpointerShmem->head;
 
 	/* Initialize temporary hash table */
 	ctl.keysize = sizeof(CheckpointerRequest);
@@ -1258,7 +1339,8 @@ CompactCheckpointerRequestQueue(void)
 	 * away preceding entries that would end up being canceled anyhow), but
 	 * it's not clear that the extra complexity would buy us anything.
 	 */
-	for (n = 0; n < CheckpointerShmem->num_requests; n++)
+	read_idx = head;
+	for (n = 0; n < num_requests; n++)
 	{
 		CheckpointerRequest *request;
 		struct CheckpointerSlotMapping *slotmap;
@@ -1271,16 +1353,19 @@ CompactCheckpointerRequestQueue(void)
 		 * CheckpointerShmemInit.  Note also that RelFileLocator had better
 		 * contain no pad bytes.
 		 */
-		request = &CheckpointerShmem->requests[n];
+		request = &CheckpointerShmem->requests[read_idx];
 		slotmap = hash_search(htab, request, HASH_ENTER, &found);
 		if (found)
 		{
 			/* Duplicate, so mark the previous occurrence as skippable */
-			skip_slot[slotmap->slot] = true;
+			skip_slot[slotmap->ring_idx] = true;
 			num_skipped++;
 		}
 		/* Remember slot containing latest occurrence of this request value */
-		slotmap->slot = n;
+		slotmap->ring_idx = read_idx;
+
+		/* Move to the next request in the ring buffer */
+		read_idx = (read_idx + 1) % max_requests;
 	}
 
 	/* Done with the hash table. */
@@ -1294,17 +1379,34 @@ CompactCheckpointerRequestQueue(void)
 	}
 
 	/* We found some duplicates; remove them. */
-	preserve_count = 0;
-	for (n = 0; n < CheckpointerShmem->num_requests; n++)
+	read_idx = write_idx = head;
+	for (n = 0; n < num_requests; n++)
 	{
-		if (skip_slot[n])
-			continue;
-		CheckpointerShmem->requests[preserve_count++] = CheckpointerShmem->requests[n];
+		/* If this slot is NOT skipped, keep it */
+		if (!skip_slot[read_idx])
+		{
+			/* If the read and write positions are different, copy the request */
+			if (write_idx != read_idx)
+				CheckpointerShmem->requests[write_idx] =
+					CheckpointerShmem->requests[read_idx];
+
+			/* Advance the write position */
+			write_idx = (write_idx + 1) % max_requests;
+		}
+
+		read_idx = (read_idx + 1) % max_requests;
 	}
+
+	/*
+	 * Update ring buffer state: head remains the same, tail moves, count
+	 * decreases
+	 */
+	CheckpointerShmem->tail = write_idx;
+	CheckpointerShmem->num_requests -= num_skipped;
+
 	ereport(DEBUG1,
 			(errmsg_internal("compacted fsync request queue from %d entries to %d entries",
-							 CheckpointerShmem->num_requests, preserve_count)));
-	CheckpointerShmem->num_requests = preserve_count;
+							 num_requests, CheckpointerShmem->num_requests)));
 
 	/* Cleanup. */
 	pfree(skip_slot);
@@ -1325,40 +1427,64 @@ AbsorbSyncRequests(void)
 {
 	CheckpointerRequest *requests = NULL;
 	CheckpointerRequest *request;
-	int			n;
+	int			n,
+				i;
+	bool		loop;
 
 	if (!AmCheckpointerProcess())
 		return;
 
-	LWLockAcquire(CheckpointerCommLock, LW_EXCLUSIVE);
-
-	/*
-	 * We try to avoid holding the lock for a long time by copying the request
-	 * array, and processing the requests after releasing the lock.
-	 *
-	 * Once we have cleared the requests from shared memory, we have to PANIC
-	 * if we then fail to absorb them (eg, because our hashtable runs out of
-	 * memory).  This is because the system cannot run safely if we are unable
-	 * to fsync what we have been told to fsync.  Fortunately, the hashtable
-	 * is so small that the problem is quite unlikely to arise in practice.
-	 */
-	n = CheckpointerShmem->num_requests;
-	if (n > 0)
+	do
 	{
-		requests = (CheckpointerRequest *) palloc(n * sizeof(CheckpointerRequest));
-		memcpy(requests, CheckpointerShmem->requests, n * sizeof(CheckpointerRequest));
-	}
+		LWLockAcquire(CheckpointerCommLock, LW_EXCLUSIVE);
+
+		/*---
+		 * We try to avoid holding the lock for a long time by:
+		 * 1. Copying the request array and processing the requests after
+		 *    releasing the lock;
+		 * 2. Processing not the whole queue, but only batches of
+		 *    CKPT_REQ_BATCH_SIZE at once.
+		 *
+		 * Once we have cleared the requests from shared memory, we must
+		 * PANIC if we then fail to absorb them (e.g., because our hashtable
+		 * runs out of memory).  This is because the system cannot run safely
+		 * if we are unable to fsync what we have been told to fsync.
+		 * Fortunately, the hashtable is so small that the problem is quite
+		 * unlikely to arise in practice.
+		 *
+		 * Note: The maximum possible size of a ring buffer is
+		 * MAX_CHECKPOINT_REQUESTS entries, which fit into a maximum palloc
+		 * allocation size of 1Gb.  Our maximum batch size,
+		 * CKPT_REQ_BATCH_SIZE, is even smaller.
+		 */
+		n = Min(CheckpointerShmem->num_requests, CKPT_REQ_BATCH_SIZE);
+		if (n > 0)
+		{
+			if (!requests)
+				requests = (CheckpointerRequest *) palloc(n * sizeof(CheckpointerRequest));
 
-	START_CRIT_SECTION();
+			for (i = 0; i < n; i++)
+			{
+				requests[i] = CheckpointerShmem->requests[CheckpointerShmem->head];
+				CheckpointerShmem->head = (CheckpointerShmem->head + 1) % CheckpointerShmem->max_requests;
+			}
 
-	CheckpointerShmem->num_requests = 0;
+			CheckpointerShmem->num_requests -= n;
 
-	LWLockRelease(CheckpointerCommLock);
+		}
+
+		START_CRIT_SECTION();
+
+		/* Are there any requests in the queue? If so, keep going. */
+		loop = CheckpointerShmem->num_requests != 0;
+
+		LWLockRelease(CheckpointerCommLock);
 
-	for (request = requests; n > 0; request++, n--)
-		RememberSyncRequest(&request->ftag, request->type);
+		for (request = requests; n > 0; request++, n--)
+			RememberSyncRequest(&request->ftag, request->type);
 
-	END_CRIT_SECTION();
+		END_CRIT_SECTION();
+	} while (loop);
 
 	if (requests)
 		pfree(requests);
diff --git a/src/backend/postmaster/pgarch.c b/src/backend/postmaster/pgarch.c
index 7e622ae4bd2a7..78e39e5f866a7 100644
--- a/src/backend/postmaster/pgarch.c
+++ b/src/backend/postmaster/pgarch.c
@@ -718,15 +718,15 @@ pgarch_readyXlog(char *xlog)
 		/*
 		 * Store the file in our max-heap if it has a high enough priority.
 		 */
-		if (arch_files->arch_heap->bh_size < NUM_FILES_PER_DIRECTORY_SCAN)
+		if (binaryheap_size(arch_files->arch_heap) < NUM_FILES_PER_DIRECTORY_SCAN)
 		{
 			/* If the heap isn't full yet, quickly add it. */
-			arch_file = arch_files->arch_filenames[arch_files->arch_heap->bh_size];
+			arch_file = arch_files->arch_filenames[binaryheap_size(arch_files->arch_heap)];
 			strcpy(arch_file, basename);
 			binaryheap_add_unordered(arch_files->arch_heap, CStringGetDatum(arch_file));
 
 			/* If we just filled the heap, make it a valid one. */
-			if (arch_files->arch_heap->bh_size == NUM_FILES_PER_DIRECTORY_SCAN)
+			if (binaryheap_size(arch_files->arch_heap) == NUM_FILES_PER_DIRECTORY_SCAN)
 				binaryheap_build(arch_files->arch_heap);
 		}
 		else if (ready_file_comparator(binaryheap_first(arch_files->arch_heap),
@@ -744,21 +744,21 @@ pgarch_readyXlog(char *xlog)
 	FreeDir(rldir);
 
 	/* If no files were found, simply return. */
-	if (arch_files->arch_heap->bh_size == 0)
+	if (binaryheap_empty(arch_files->arch_heap))
 		return false;
 
 	/*
 	 * If we didn't fill the heap, we didn't make it a valid one.  Do that
 	 * now.
 	 */
-	if (arch_files->arch_heap->bh_size < NUM_FILES_PER_DIRECTORY_SCAN)
+	if (binaryheap_size(arch_files->arch_heap) < NUM_FILES_PER_DIRECTORY_SCAN)
 		binaryheap_build(arch_files->arch_heap);
 
 	/*
 	 * Fill arch_files array with the files to archive in ascending order of
 	 * priority.
 	 */
-	arch_files->arch_files_size = arch_files->arch_heap->bh_size;
+	arch_files->arch_files_size = binaryheap_size(arch_files->arch_heap);
 	for (int i = 0; i < arch_files->arch_files_size; i++)
 		arch_files->arch_files[i] = DatumGetCString(binaryheap_remove_first(arch_files->arch_heap));
 
diff --git a/src/backend/postmaster/pmchild.c b/src/backend/postmaster/pmchild.c
index cde1d23a4ca8b..584bb58c8abaf 100644
--- a/src/backend/postmaster/pmchild.c
+++ b/src/backend/postmaster/pmchild.c
@@ -59,6 +59,17 @@ NON_EXEC_STATIC int num_pmchild_slots = 0;
  */
 dlist_head	ActiveChildList;
 
+/*
+ * Dummy pointer to persuade Valgrind that we've not leaked the array of
+ * PMChild structs.  Make it global to ensure the compiler doesn't
+ * optimize it away.
+ */
+#ifdef USE_VALGRIND
+extern PMChild *pmchild_array;
+PMChild    *pmchild_array;
+#endif
+
+
 /*
  * MaxLivePostmasterChildren
  *
@@ -125,8 +136,13 @@ InitPostmasterChildSlots(void)
 	for (int i = 0; i < BACKEND_NUM_TYPES; i++)
 		num_pmchild_slots += pmchild_pools[i].size;
 
-	/* Initialize them */
+	/* Allocate enough slots, and make sure Valgrind doesn't complain */
 	slots = palloc(num_pmchild_slots * sizeof(PMChild));
+#ifdef USE_VALGRIND
+	pmchild_array = slots;
+#endif
+
+	/* Initialize them */
 	slotno = 0;
 	for (int btype = 0; btype < BACKEND_NUM_TYPES; btype++)
 	{
diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index 490f7ce36645b..e01d9f0cfe81e 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -2630,6 +2630,13 @@ CleanupBackend(PMChild *bp,
 	}
 	bp = NULL;
 
+	/*
+	 * In a crash case, exit immediately without resetting background worker
+	 * state. However, if restart_after_crash is enabled, the background
+	 * worker state (e.g., rw_pid) still needs be reset so the worker can
+	 * restart after crash recovery. This reset is handled in
+	 * ResetBackgroundWorkerCrashTimes(), not here.
+	 */
 	if (crashed)
 	{
 		HandleChildCrash(bp_pid, exitstatus, procname);
@@ -4337,15 +4344,15 @@ maybe_start_bgworkers(void)
 static bool
 maybe_reap_io_worker(int pid)
 {
-	for (int id = 0; id < MAX_IO_WORKERS; ++id)
+	for (int i = 0; i < MAX_IO_WORKERS; ++i)
 	{
-		if (io_worker_children[id] &&
-			io_worker_children[id]->pid == pid)
+		if (io_worker_children[i] &&
+			io_worker_children[i]->pid == pid)
 		{
-			ReleasePostmasterChildSlot(io_worker_children[id]);
+			ReleasePostmasterChildSlot(io_worker_children[i]);
 
 			--io_worker_count;
-			io_worker_children[id] = NULL;
+			io_worker_children[i] = NULL;
 			return true;
 		}
 	}
@@ -4389,22 +4396,22 @@ maybe_adjust_io_workers(void)
 	while (io_worker_count < io_workers)
 	{
 		PMChild    *child;
-		int			id;
+		int			i;
 
 		/* find unused entry in io_worker_children array */
-		for (id = 0; id < MAX_IO_WORKERS; ++id)
+		for (i = 0; i < MAX_IO_WORKERS; ++i)
 		{
-			if (io_worker_children[id] == NULL)
+			if (io_worker_children[i] == NULL)
 				break;
 		}
-		if (id == MAX_IO_WORKERS)
-			elog(ERROR, "could not find a free IO worker ID");
+		if (i == MAX_IO_WORKERS)
+			elog(ERROR, "could not find a free IO worker slot");
 
 		/* Try to launch one. */
 		child = StartChildProcess(B_IO_WORKER);
 		if (child != NULL)
 		{
-			io_worker_children[id] = child;
+			io_worker_children[i] = child;
 			++io_worker_count;
 		}
 		else
@@ -4415,11 +4422,11 @@ maybe_adjust_io_workers(void)
 	if (io_worker_count > io_workers)
 	{
 		/* ask the IO worker in the highest slot to exit */
-		for (int id = MAX_IO_WORKERS - 1; id >= 0; --id)
+		for (int i = MAX_IO_WORKERS - 1; i >= 0; --i)
 		{
-			if (io_worker_children[id] != NULL)
+			if (io_worker_children[i] != NULL)
 			{
-				kill(io_worker_children[id]->pid, SIGUSR2);
+				kill(io_worker_children[i]->pid, SIGUSR2);
 				break;
 			}
 		}
diff --git a/src/backend/postmaster/walsummarizer.c b/src/backend/postmaster/walsummarizer.c
index 0fec4f1f871ce..777c9a8d5553b 100644
--- a/src/backend/postmaster/walsummarizer.c
+++ b/src/backend/postmaster/walsummarizer.c
@@ -385,7 +385,7 @@ WalSummarizerMain(const void *startup_data, size_t startup_data_len)
 
 			switch_lsn = tliSwitchPoint(current_tli, tles, &switch_tli);
 			ereport(DEBUG1,
-					errmsg_internal("switch point from TLI %u to TLI %u is at %X/%X",
+					errmsg_internal("switch point from TLI %u to TLI %u is at %X/%08X",
 									current_tli, switch_tli, LSN_FORMAT_ARGS(switch_lsn)));
 		}
 
@@ -741,7 +741,7 @@ WaitForWalSummarization(XLogRecPtr lsn)
 				ereport(ERROR,
 						(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
 						 errmsg("WAL summarization is not progressing"),
-						 errdetail("Summarization is needed through %X/%X, but is stuck at %X/%X on disk and %X/%X in memory.",
+						 errdetail("Summarization is needed through %X/%08X, but is stuck at %X/%08X on disk and %X/%08X in memory.",
 								   LSN_FORMAT_ARGS(lsn),
 								   LSN_FORMAT_ARGS(summarized_lsn),
 								   LSN_FORMAT_ARGS(pending_lsn))));
@@ -755,12 +755,12 @@ WaitForWalSummarization(XLogRecPtr lsn)
 												current_time) / 1000;
 			ereport(WARNING,
 					(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-					 errmsg_plural("still waiting for WAL summarization through %X/%X after %ld second",
-								   "still waiting for WAL summarization through %X/%X after %ld seconds",
+					 errmsg_plural("still waiting for WAL summarization through %X/%08X after %ld second",
+								   "still waiting for WAL summarization through %X/%08X after %ld seconds",
 								   elapsed_seconds,
 								   LSN_FORMAT_ARGS(lsn),
 								   elapsed_seconds),
-					 errdetail("Summarization has reached %X/%X on disk and %X/%X in memory.",
+					 errdetail("Summarization has reached %X/%08X on disk and %X/%08X in memory.",
 							   LSN_FORMAT_ARGS(summarized_lsn),
 							   LSN_FORMAT_ARGS(pending_lsn))));
 		}
@@ -981,7 +981,7 @@ SummarizeWAL(TimeLineID tli, XLogRecPtr start_lsn, bool exact,
 			if (private_data->end_of_wal)
 			{
 				ereport(DEBUG1,
-						errmsg_internal("could not read WAL from timeline %u at %X/%X: end of WAL at %X/%X",
+						errmsg_internal("could not read WAL from timeline %u at %X/%08X: end of WAL at %X/%08X",
 										tli,
 										LSN_FORMAT_ARGS(start_lsn),
 										LSN_FORMAT_ARGS(private_data->read_upto)));
@@ -1000,8 +1000,8 @@ SummarizeWAL(TimeLineID tli, XLogRecPtr start_lsn, bool exact,
 			}
 			else
 				ereport(ERROR,
-						(errmsg("could not find a valid record after %X/%X",
-								LSN_FORMAT_ARGS(start_lsn))));
+						errmsg("could not find a valid record after %X/%08X",
+							   LSN_FORMAT_ARGS(start_lsn)));
 		}
 
 		/* We shouldn't go backward. */
@@ -1034,7 +1034,7 @@ SummarizeWAL(TimeLineID tli, XLogRecPtr start_lsn, bool exact,
 				 * able to read a complete record.
 				 */
 				ereport(DEBUG1,
-						errmsg_internal("could not read WAL from timeline %u at %X/%X: end of WAL at %X/%X",
+						errmsg_internal("could not read WAL from timeline %u at %X/%08X: end of WAL at %X/%08X",
 										tli,
 										LSN_FORMAT_ARGS(xlogreader->EndRecPtr),
 										LSN_FORMAT_ARGS(private_data->read_upto)));
@@ -1045,13 +1045,13 @@ SummarizeWAL(TimeLineID tli, XLogRecPtr start_lsn, bool exact,
 			if (errormsg)
 				ereport(ERROR,
 						(errcode_for_file_access(),
-						 errmsg("could not read WAL from timeline %u at %X/%X: %s",
+						 errmsg("could not read WAL from timeline %u at %X/%08X: %s",
 								tli, LSN_FORMAT_ARGS(xlogreader->EndRecPtr),
 								errormsg)));
 			else
 				ereport(ERROR,
 						(errcode_for_file_access(),
-						 errmsg("could not read WAL from timeline %u at %X/%X",
+						 errmsg("could not read WAL from timeline %u at %X/%08X",
 								tli, LSN_FORMAT_ARGS(xlogreader->EndRecPtr))));
 		}
 
@@ -1222,7 +1222,7 @@ SummarizeWAL(TimeLineID tli, XLogRecPtr start_lsn, bool exact,
 
 		/* Tell the user what we did. */
 		ereport(DEBUG1,
-				errmsg_internal("summarized WAL on TLI %u from %X/%X to %X/%X",
+				errmsg_internal("summarized WAL on TLI %u from %X/%08X to %X/%08X",
 								tli,
 								LSN_FORMAT_ARGS(summary_start_lsn),
 								LSN_FORMAT_ARGS(summary_end_lsn)));
@@ -1234,7 +1234,7 @@ SummarizeWAL(TimeLineID tli, XLogRecPtr start_lsn, bool exact,
 	/* If we skipped a non-zero amount of WAL, log a debug message. */
 	if (summary_end_lsn > summary_start_lsn && fast_forward)
 		ereport(DEBUG1,
-				errmsg_internal("skipped summarizing WAL on TLI %u from %X/%X to %X/%X",
+				errmsg_internal("skipped summarizing WAL on TLI %u from %X/%08X to %X/%08X",
 								tli,
 								LSN_FORMAT_ARGS(summary_start_lsn),
 								LSN_FORMAT_ARGS(summary_end_lsn)));
@@ -1580,7 +1580,7 @@ summarizer_read_local_xlog_page(XLogReaderState *state,
 
 					/* Debugging output. */
 					ereport(DEBUG1,
-							errmsg_internal("timeline %u became historic, can read up to %X/%X",
+							errmsg_internal("timeline %u became historic, can read up to %X/%08X",
 											private_data->tli, LSN_FORMAT_ARGS(private_data->read_upto)));
 				}
 
diff --git a/src/backend/regex/regc_pg_locale.c b/src/backend/regex/regc_pg_locale.c
index 78193cfb964e5..d9eab5357bc38 100644
--- a/src/backend/regex/regc_pg_locale.c
+++ b/src/backend/regex/regc_pg_locale.c
@@ -20,58 +20,13 @@
 #include "common/unicode_category.h"
 #include "utils/pg_locale.h"
 
-/*
- * For the libc provider, to provide as much functionality as possible on a
- * variety of platforms without going so far as to implement everything from
- * scratch, we use several implementation strategies depending on the
- * situation:
- *
- * 1. In C/POSIX collations, we use hard-wired code.  We can't depend on
- * the <ctype.h> functions since those will obey LC_CTYPE.  Note that these
- * collations don't give a fig about multibyte characters.
- *
- * 2. When working in UTF8 encoding, we use the <wctype.h> functions.
- * This assumes that every platform uses Unicode codepoints directly
- * as the wchar_t representation of Unicode.  (XXX: ICU makes this assumption
- * even for non-UTF8 encodings, which may be a problem.)  On some platforms
- * wchar_t is only 16 bits wide, so we have to punt for codepoints > 0xFFFF.
- *
- * 3. In all other encodings, we use the <ctype.h> functions for pg_wchar
- * values up to 255, and punt for values above that.  This is 100% correct
- * only in single-byte encodings such as LATINn.  However, non-Unicode
- * multibyte encodings are mostly Far Eastern character sets for which the
- * properties being tested here aren't very relevant for higher code values
- * anyway.  The difficulty with using the <wctype.h> functions with
- * non-Unicode multibyte encodings is that we can have no certainty that
- * the platform's wchar_t representation matches what we do in pg_wchar
- * conversions.
- *
- * As a special case, in the "default" collation, (2) and (3) force ASCII
- * letters to follow ASCII upcase/downcase rules, while in a non-default
- * collation we just let the library functions do what they will.  The case
- * where this matters is treatment of I/i in Turkish, and the behavior is
- * meant to match the upper()/lower() SQL functions.
- *
- * We store the active collation setting in static variables.  In principle
- * it could be passed down to here via the regex library's "struct vars" data
- * structure; but that would require somewhat invasive changes in the regex
- * library, and right now there's no real benefit to be gained from that.
- *
- * NB: the coding here assumes pg_wchar is an unsigned type.
- */
-
-typedef enum
-{
-	PG_REGEX_STRATEGY_C,		/* C locale (encoding independent) */
-	PG_REGEX_STRATEGY_BUILTIN,	/* built-in Unicode semantics */
-	PG_REGEX_STRATEGY_LIBC_WIDE,	/* Use locale_t <wctype.h> functions */
-	PG_REGEX_STRATEGY_LIBC_1BYTE,	/* Use locale_t <ctype.h> functions */
-	PG_REGEX_STRATEGY_ICU,		/* Use ICU uchar.h functions */
-} PG_Locale_Strategy;
-
-static PG_Locale_Strategy pg_regex_strategy;
 static pg_locale_t pg_regex_locale;
 
+static struct pg_locale_struct dummy_c_locale = {
+	.collate_is_c = true,
+	.ctype_is_c = true,
+};
+
 /*
  * Hard-wired character properties for C locale
  */
@@ -228,7 +183,6 @@ void
 pg_set_regex_collation(Oid collation)
 {
 	pg_locale_t locale = 0;
-	PG_Locale_Strategy strategy;
 
 	if (!OidIsValid(collation))
 	{
@@ -249,8 +203,7 @@ pg_set_regex_collation(Oid collation)
 		 * catalog access is available, so we can't call
 		 * pg_newlocale_from_collation().
 		 */
-		strategy = PG_REGEX_STRATEGY_C;
-		locale = 0;
+		locale = &dummy_c_locale;
 	}
 	else
 	{
@@ -267,113 +220,41 @@ pg_set_regex_collation(Oid collation)
 			 * C/POSIX collations use this path regardless of database
 			 * encoding
 			 */
-			strategy = PG_REGEX_STRATEGY_C;
-			locale = 0;
-		}
-		else if (locale->provider == COLLPROVIDER_BUILTIN)
-		{
-			Assert(GetDatabaseEncoding() == PG_UTF8);
-			strategy = PG_REGEX_STRATEGY_BUILTIN;
-		}
-#ifdef USE_ICU
-		else if (locale->provider == COLLPROVIDER_ICU)
-		{
-			strategy = PG_REGEX_STRATEGY_ICU;
-		}
-#endif
-		else
-		{
-			Assert(locale->provider == COLLPROVIDER_LIBC);
-			if (GetDatabaseEncoding() == PG_UTF8)
-				strategy = PG_REGEX_STRATEGY_LIBC_WIDE;
-			else
-				strategy = PG_REGEX_STRATEGY_LIBC_1BYTE;
+			locale = &dummy_c_locale;
 		}
 	}
 
-	pg_regex_strategy = strategy;
 	pg_regex_locale = locale;
 }
 
 static int
 pg_wc_isdigit(pg_wchar c)
 {
-	switch (pg_regex_strategy)
-	{
-		case PG_REGEX_STRATEGY_C:
-			return (c <= (pg_wchar) 127 &&
-					(pg_char_properties[c] & PG_ISDIGIT));
-		case PG_REGEX_STRATEGY_BUILTIN:
-			return pg_u_isdigit(c, !pg_regex_locale->info.builtin.casemap_full);
-		case PG_REGEX_STRATEGY_LIBC_WIDE:
-			if (sizeof(wchar_t) >= 4 || c <= (pg_wchar) 0xFFFF)
-				return iswdigit_l((wint_t) c, pg_regex_locale->info.lt);
-			/* FALL THRU */
-		case PG_REGEX_STRATEGY_LIBC_1BYTE:
-			return (c <= (pg_wchar) UCHAR_MAX &&
-					isdigit_l((unsigned char) c, pg_regex_locale->info.lt));
-			break;
-		case PG_REGEX_STRATEGY_ICU:
-#ifdef USE_ICU
-			return u_isdigit(c);
-#endif
-			break;
-	}
-	return 0;					/* can't get here, but keep compiler quiet */
+	if (pg_regex_locale->ctype_is_c)
+		return (c <= (pg_wchar) 127 &&
+				(pg_char_properties[c] & PG_ISDIGIT));
+	else
+		return pg_regex_locale->ctype->wc_isdigit(c, pg_regex_locale);
 }
 
 static int
 pg_wc_isalpha(pg_wchar c)
 {
-	switch (pg_regex_strategy)
-	{
-		case PG_REGEX_STRATEGY_C:
-			return (c <= (pg_wchar) 127 &&
-					(pg_char_properties[c] & PG_ISALPHA));
-		case PG_REGEX_STRATEGY_BUILTIN:
-			return pg_u_isalpha(c);
-		case PG_REGEX_STRATEGY_LIBC_WIDE:
-			if (sizeof(wchar_t) >= 4 || c <= (pg_wchar) 0xFFFF)
-				return iswalpha_l((wint_t) c, pg_regex_locale->info.lt);
-			/* FALL THRU */
-		case PG_REGEX_STRATEGY_LIBC_1BYTE:
-			return (c <= (pg_wchar) UCHAR_MAX &&
-					isalpha_l((unsigned char) c, pg_regex_locale->info.lt));
-			break;
-		case PG_REGEX_STRATEGY_ICU:
-#ifdef USE_ICU
-			return u_isalpha(c);
-#endif
-			break;
-	}
-	return 0;					/* can't get here, but keep compiler quiet */
+	if (pg_regex_locale->ctype_is_c)
+		return (c <= (pg_wchar) 127 &&
+				(pg_char_properties[c] & PG_ISALPHA));
+	else
+		return pg_regex_locale->ctype->wc_isalpha(c, pg_regex_locale);
 }
 
 static int
 pg_wc_isalnum(pg_wchar c)
 {
-	switch (pg_regex_strategy)
-	{
-		case PG_REGEX_STRATEGY_C:
-			return (c <= (pg_wchar) 127 &&
-					(pg_char_properties[c] & PG_ISALNUM));
-		case PG_REGEX_STRATEGY_BUILTIN:
-			return pg_u_isalnum(c, !pg_regex_locale->info.builtin.casemap_full);
-		case PG_REGEX_STRATEGY_LIBC_WIDE:
-			if (sizeof(wchar_t) >= 4 || c <= (pg_wchar) 0xFFFF)
-				return iswalnum_l((wint_t) c, pg_regex_locale->info.lt);
-			/* FALL THRU */
-		case PG_REGEX_STRATEGY_LIBC_1BYTE:
-			return (c <= (pg_wchar) UCHAR_MAX &&
-					isalnum_l((unsigned char) c, pg_regex_locale->info.lt));
-			break;
-		case PG_REGEX_STRATEGY_ICU:
-#ifdef USE_ICU
-			return u_isalnum(c);
-#endif
-			break;
-	}
-	return 0;					/* can't get here, but keep compiler quiet */
+	if (pg_regex_locale->ctype_is_c)
+		return (c <= (pg_wchar) 127 &&
+				(pg_char_properties[c] & PG_ISALNUM));
+	else
+		return pg_regex_locale->ctype->wc_isalnum(c, pg_regex_locale);
 }
 
 static int
@@ -388,231 +269,87 @@ pg_wc_isword(pg_wchar c)
 static int
 pg_wc_isupper(pg_wchar c)
 {
-	switch (pg_regex_strategy)
-	{
-		case PG_REGEX_STRATEGY_C:
-			return (c <= (pg_wchar) 127 &&
-					(pg_char_properties[c] & PG_ISUPPER));
-		case PG_REGEX_STRATEGY_BUILTIN:
-			return pg_u_isupper(c);
-		case PG_REGEX_STRATEGY_LIBC_WIDE:
-			if (sizeof(wchar_t) >= 4 || c <= (pg_wchar) 0xFFFF)
-				return iswupper_l((wint_t) c, pg_regex_locale->info.lt);
-			/* FALL THRU */
-		case PG_REGEX_STRATEGY_LIBC_1BYTE:
-			return (c <= (pg_wchar) UCHAR_MAX &&
-					isupper_l((unsigned char) c, pg_regex_locale->info.lt));
-			break;
-		case PG_REGEX_STRATEGY_ICU:
-#ifdef USE_ICU
-			return u_isupper(c);
-#endif
-			break;
-	}
-	return 0;					/* can't get here, but keep compiler quiet */
+	if (pg_regex_locale->ctype_is_c)
+		return (c <= (pg_wchar) 127 &&
+				(pg_char_properties[c] & PG_ISUPPER));
+	else
+		return pg_regex_locale->ctype->wc_isupper(c, pg_regex_locale);
 }
 
 static int
 pg_wc_islower(pg_wchar c)
 {
-	switch (pg_regex_strategy)
-	{
-		case PG_REGEX_STRATEGY_C:
-			return (c <= (pg_wchar) 127 &&
-					(pg_char_properties[c] & PG_ISLOWER));
-		case PG_REGEX_STRATEGY_BUILTIN:
-			return pg_u_islower(c);
-		case PG_REGEX_STRATEGY_LIBC_WIDE:
-			if (sizeof(wchar_t) >= 4 || c <= (pg_wchar) 0xFFFF)
-				return iswlower_l((wint_t) c, pg_regex_locale->info.lt);
-			/* FALL THRU */
-		case PG_REGEX_STRATEGY_LIBC_1BYTE:
-			return (c <= (pg_wchar) UCHAR_MAX &&
-					islower_l((unsigned char) c, pg_regex_locale->info.lt));
-			break;
-		case PG_REGEX_STRATEGY_ICU:
-#ifdef USE_ICU
-			return u_islower(c);
-#endif
-			break;
-	}
-	return 0;					/* can't get here, but keep compiler quiet */
+	if (pg_regex_locale->ctype_is_c)
+		return (c <= (pg_wchar) 127 &&
+				(pg_char_properties[c] & PG_ISLOWER));
+	else
+		return pg_regex_locale->ctype->wc_islower(c, pg_regex_locale);
 }
 
 static int
 pg_wc_isgraph(pg_wchar c)
 {
-	switch (pg_regex_strategy)
-	{
-		case PG_REGEX_STRATEGY_C:
-			return (c <= (pg_wchar) 127 &&
-					(pg_char_properties[c] & PG_ISGRAPH));
-		case PG_REGEX_STRATEGY_BUILTIN:
-			return pg_u_isgraph(c);
-		case PG_REGEX_STRATEGY_LIBC_WIDE:
-			if (sizeof(wchar_t) >= 4 || c <= (pg_wchar) 0xFFFF)
-				return iswgraph_l((wint_t) c, pg_regex_locale->info.lt);
-			/* FALL THRU */
-		case PG_REGEX_STRATEGY_LIBC_1BYTE:
-			return (c <= (pg_wchar) UCHAR_MAX &&
-					isgraph_l((unsigned char) c, pg_regex_locale->info.lt));
-			break;
-		case PG_REGEX_STRATEGY_ICU:
-#ifdef USE_ICU
-			return u_isgraph(c);
-#endif
-			break;
-	}
-	return 0;					/* can't get here, but keep compiler quiet */
+	if (pg_regex_locale->ctype_is_c)
+		return (c <= (pg_wchar) 127 &&
+				(pg_char_properties[c] & PG_ISGRAPH));
+	else
+		return pg_regex_locale->ctype->wc_isgraph(c, pg_regex_locale);
 }
 
 static int
 pg_wc_isprint(pg_wchar c)
 {
-	switch (pg_regex_strategy)
-	{
-		case PG_REGEX_STRATEGY_C:
-			return (c <= (pg_wchar) 127 &&
-					(pg_char_properties[c] & PG_ISPRINT));
-		case PG_REGEX_STRATEGY_BUILTIN:
-			return pg_u_isprint(c);
-		case PG_REGEX_STRATEGY_LIBC_WIDE:
-			if (sizeof(wchar_t) >= 4 || c <= (pg_wchar) 0xFFFF)
-				return iswprint_l((wint_t) c, pg_regex_locale->info.lt);
-			/* FALL THRU */
-		case PG_REGEX_STRATEGY_LIBC_1BYTE:
-			return (c <= (pg_wchar) UCHAR_MAX &&
-					isprint_l((unsigned char) c, pg_regex_locale->info.lt));
-			break;
-		case PG_REGEX_STRATEGY_ICU:
-#ifdef USE_ICU
-			return u_isprint(c);
-#endif
-			break;
-	}
-	return 0;					/* can't get here, but keep compiler quiet */
+	if (pg_regex_locale->ctype_is_c)
+		return (c <= (pg_wchar) 127 &&
+				(pg_char_properties[c] & PG_ISPRINT));
+	else
+		return pg_regex_locale->ctype->wc_isprint(c, pg_regex_locale);
 }
 
 static int
 pg_wc_ispunct(pg_wchar c)
 {
-	switch (pg_regex_strategy)
-	{
-		case PG_REGEX_STRATEGY_C:
-			return (c <= (pg_wchar) 127 &&
-					(pg_char_properties[c] & PG_ISPUNCT));
-		case PG_REGEX_STRATEGY_BUILTIN:
-			return pg_u_ispunct(c, !pg_regex_locale->info.builtin.casemap_full);
-		case PG_REGEX_STRATEGY_LIBC_WIDE:
-			if (sizeof(wchar_t) >= 4 || c <= (pg_wchar) 0xFFFF)
-				return iswpunct_l((wint_t) c, pg_regex_locale->info.lt);
-			/* FALL THRU */
-		case PG_REGEX_STRATEGY_LIBC_1BYTE:
-			return (c <= (pg_wchar) UCHAR_MAX &&
-					ispunct_l((unsigned char) c, pg_regex_locale->info.lt));
-			break;
-		case PG_REGEX_STRATEGY_ICU:
-#ifdef USE_ICU
-			return u_ispunct(c);
-#endif
-			break;
-	}
-	return 0;					/* can't get here, but keep compiler quiet */
+	if (pg_regex_locale->ctype_is_c)
+		return (c <= (pg_wchar) 127 &&
+				(pg_char_properties[c] & PG_ISPUNCT));
+	else
+		return pg_regex_locale->ctype->wc_ispunct(c, pg_regex_locale);
 }
 
 static int
 pg_wc_isspace(pg_wchar c)
 {
-	switch (pg_regex_strategy)
-	{
-		case PG_REGEX_STRATEGY_C:
-			return (c <= (pg_wchar) 127 &&
-					(pg_char_properties[c] & PG_ISSPACE));
-		case PG_REGEX_STRATEGY_BUILTIN:
-			return pg_u_isspace(c);
-		case PG_REGEX_STRATEGY_LIBC_WIDE:
-			if (sizeof(wchar_t) >= 4 || c <= (pg_wchar) 0xFFFF)
-				return iswspace_l((wint_t) c, pg_regex_locale->info.lt);
-			/* FALL THRU */
-		case PG_REGEX_STRATEGY_LIBC_1BYTE:
-			return (c <= (pg_wchar) UCHAR_MAX &&
-					isspace_l((unsigned char) c, pg_regex_locale->info.lt));
-			break;
-		case PG_REGEX_STRATEGY_ICU:
-#ifdef USE_ICU
-			return u_isspace(c);
-#endif
-			break;
-	}
-	return 0;					/* can't get here, but keep compiler quiet */
+	if (pg_regex_locale->ctype_is_c)
+		return (c <= (pg_wchar) 127 &&
+				(pg_char_properties[c] & PG_ISSPACE));
+	else
+		return pg_regex_locale->ctype->wc_isspace(c, pg_regex_locale);
 }
 
 static pg_wchar
 pg_wc_toupper(pg_wchar c)
 {
-	switch (pg_regex_strategy)
+	if (pg_regex_locale->ctype_is_c)
 	{
-		case PG_REGEX_STRATEGY_C:
-			if (c <= (pg_wchar) 127)
-				return pg_ascii_toupper((unsigned char) c);
-			return c;
-		case PG_REGEX_STRATEGY_BUILTIN:
-			return unicode_uppercase_simple(c);
-		case PG_REGEX_STRATEGY_LIBC_WIDE:
-			/* force C behavior for ASCII characters, per comments above */
-			if (pg_regex_locale->is_default && c <= (pg_wchar) 127)
-				return pg_ascii_toupper((unsigned char) c);
-			if (sizeof(wchar_t) >= 4 || c <= (pg_wchar) 0xFFFF)
-				return towupper_l((wint_t) c, pg_regex_locale->info.lt);
-			/* FALL THRU */
-		case PG_REGEX_STRATEGY_LIBC_1BYTE:
-			/* force C behavior for ASCII characters, per comments above */
-			if (pg_regex_locale->is_default && c <= (pg_wchar) 127)
-				return pg_ascii_toupper((unsigned char) c);
-			if (c <= (pg_wchar) UCHAR_MAX)
-				return toupper_l((unsigned char) c, pg_regex_locale->info.lt);
-			return c;
-		case PG_REGEX_STRATEGY_ICU:
-#ifdef USE_ICU
-			return u_toupper(c);
-#endif
-			break;
+		if (c <= (pg_wchar) 127)
+			return pg_ascii_toupper((unsigned char) c);
+		return c;
 	}
-	return 0;					/* can't get here, but keep compiler quiet */
+	else
+		return pg_regex_locale->ctype->wc_toupper(c, pg_regex_locale);
 }
 
 static pg_wchar
 pg_wc_tolower(pg_wchar c)
 {
-	switch (pg_regex_strategy)
+	if (pg_regex_locale->ctype_is_c)
 	{
-		case PG_REGEX_STRATEGY_C:
-			if (c <= (pg_wchar) 127)
-				return pg_ascii_tolower((unsigned char) c);
-			return c;
-		case PG_REGEX_STRATEGY_BUILTIN:
-			return unicode_lowercase_simple(c);
-		case PG_REGEX_STRATEGY_LIBC_WIDE:
-			/* force C behavior for ASCII characters, per comments above */
-			if (pg_regex_locale->is_default && c <= (pg_wchar) 127)
-				return pg_ascii_tolower((unsigned char) c);
-			if (sizeof(wchar_t) >= 4 || c <= (pg_wchar) 0xFFFF)
-				return towlower_l((wint_t) c, pg_regex_locale->info.lt);
-			/* FALL THRU */
-		case PG_REGEX_STRATEGY_LIBC_1BYTE:
-			/* force C behavior for ASCII characters, per comments above */
-			if (pg_regex_locale->is_default && c <= (pg_wchar) 127)
-				return pg_ascii_tolower((unsigned char) c);
-			if (c <= (pg_wchar) UCHAR_MAX)
-				return tolower_l((unsigned char) c, pg_regex_locale->info.lt);
-			return c;
-		case PG_REGEX_STRATEGY_ICU:
-#ifdef USE_ICU
-			return u_tolower(c);
-#endif
-			break;
+		if (c <= (pg_wchar) 127)
+			return pg_ascii_tolower((unsigned char) c);
+		return c;
 	}
-	return 0;					/* can't get here, but keep compiler quiet */
+	else
+		return pg_regex_locale->ctype->wc_tolower(c, pg_regex_locale);
 }
 
 
@@ -738,37 +475,25 @@ pg_ctype_get_cache(pg_wc_probefunc probefunc, int cclasscode)
 	 * would always be true for production values of MAX_SIMPLE_CHR, but it's
 	 * useful to allow it to be small for testing purposes.)
 	 */
-	switch (pg_regex_strategy)
+	if (pg_regex_locale->ctype_is_c)
 	{
-		case PG_REGEX_STRATEGY_C:
 #if MAX_SIMPLE_CHR >= 127
-			max_chr = (pg_wchar) 127;
-			pcc->cv.cclasscode = -1;
+		max_chr = (pg_wchar) 127;
+		pcc->cv.cclasscode = -1;
 #else
-			max_chr = (pg_wchar) MAX_SIMPLE_CHR;
+		max_chr = (pg_wchar) MAX_SIMPLE_CHR;
 #endif
-			break;
-		case PG_REGEX_STRATEGY_BUILTIN:
-			max_chr = (pg_wchar) MAX_SIMPLE_CHR;
-			break;
-		case PG_REGEX_STRATEGY_LIBC_WIDE:
-			max_chr = (pg_wchar) MAX_SIMPLE_CHR;
-			break;
-		case PG_REGEX_STRATEGY_LIBC_1BYTE:
-#if MAX_SIMPLE_CHR >= UCHAR_MAX
-			max_chr = (pg_wchar) UCHAR_MAX;
+	}
+	else
+	{
+		if (pg_regex_locale->ctype->max_chr != 0 &&
+			pg_regex_locale->ctype->max_chr <= MAX_SIMPLE_CHR)
+		{
+			max_chr = pg_regex_locale->ctype->max_chr;
 			pcc->cv.cclasscode = -1;
-#else
-			max_chr = (pg_wchar) MAX_SIMPLE_CHR;
-#endif
-			break;
-		case PG_REGEX_STRATEGY_ICU:
+		}
+		else
 			max_chr = (pg_wchar) MAX_SIMPLE_CHR;
-			break;
-		default:
-			Assert(false);
-			max_chr = 0;		/* can't get here, but keep compiler quiet */
-			break;
 	}
 
 	/*
diff --git a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
index 7b4ddf7a8f52f..239641bfbb66a 100644
--- a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
+++ b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
@@ -232,6 +232,9 @@ libpqrcv_connect(const char *conninfo, bool replication, bool logical,
 				 errhint("Target server's authentication method must be changed, or set password_required=false in the subscription parameters.")));
 	}
 
+	PQsetNoticeReceiver(conn->streamConn, libpqsrv_notice_receiver,
+						"received message via replication");
+
 	/*
 	 * Set always-secure search path for the cases where the connection is
 	 * used to run SQL queries, so malicious users can't get control.
@@ -418,31 +421,22 @@ libpqrcv_identify_system(WalReceiverConn *conn, TimeLineID *primary_tli)
 						"IDENTIFY_SYSTEM",
 						WAIT_EVENT_LIBPQWALRECEIVER_RECEIVE);
 	if (PQresultStatus(res) != PGRES_TUPLES_OK)
-	{
-		PQclear(res);
 		ereport(ERROR,
 				(errcode(ERRCODE_PROTOCOL_VIOLATION),
 				 errmsg("could not receive database system identifier and timeline ID from "
 						"the primary server: %s",
 						pchomp(PQerrorMessage(conn->streamConn)))));
-	}
 
 	/*
 	 * IDENTIFY_SYSTEM returns 3 columns in 9.3 and earlier, and 4 columns in
 	 * 9.4 and onwards.
 	 */
 	if (PQnfields(res) < 3 || PQntuples(res) != 1)
-	{
-		int			ntuples = PQntuples(res);
-		int			nfields = PQnfields(res);
-
-		PQclear(res);
 		ereport(ERROR,
 				(errcode(ERRCODE_PROTOCOL_VIOLATION),
 				 errmsg("invalid response from primary server"),
 				 errdetail("Could not identify system: got %d rows and %d fields, expected %d rows and %d or more fields.",
-						   ntuples, nfields, 1, 3)));
-	}
+						   PQntuples(res), PQnfields(res), 1, 3)));
 	primary_sysid = pstrdup(PQgetvalue(res, 0, 0));
 	*primary_tli = pg_strtoint32(PQgetvalue(res, 0, 1));
 	PQclear(res);
@@ -534,7 +528,7 @@ libpqrcv_startstreaming(WalReceiverConn *conn,
 	if (options->logical)
 		appendStringInfoString(&cmd, " LOGICAL");
 
-	appendStringInfo(&cmd, " %X/%X", LSN_FORMAT_ARGS(options->startpoint));
+	appendStringInfo(&cmd, " %X/%08X", LSN_FORMAT_ARGS(options->startpoint));
 
 	/*
 	 * Additional options are different depending on if we are doing logical
@@ -604,13 +598,10 @@ libpqrcv_startstreaming(WalReceiverConn *conn,
 		return false;
 	}
 	else if (PQresultStatus(res) != PGRES_COPY_BOTH)
-	{
-		PQclear(res);
 		ereport(ERROR,
 				(errcode(ERRCODE_PROTOCOL_VIOLATION),
 				 errmsg("could not start WAL streaming: %s",
 						pchomp(PQerrorMessage(conn->streamConn)))));
-	}
 	PQclear(res);
 	return true;
 }
@@ -718,26 +709,17 @@ libpqrcv_readtimelinehistoryfile(WalReceiverConn *conn,
 						cmd,
 						WAIT_EVENT_LIBPQWALRECEIVER_RECEIVE);
 	if (PQresultStatus(res) != PGRES_TUPLES_OK)
-	{
-		PQclear(res);
 		ereport(ERROR,
 				(errcode(ERRCODE_PROTOCOL_VIOLATION),
 				 errmsg("could not receive timeline history file from "
 						"the primary server: %s",
 						pchomp(PQerrorMessage(conn->streamConn)))));
-	}
 	if (PQnfields(res) != 2 || PQntuples(res) != 1)
-	{
-		int			ntuples = PQntuples(res);
-		int			nfields = PQnfields(res);
-
-		PQclear(res);
 		ereport(ERROR,
 				(errcode(ERRCODE_PROTOCOL_VIOLATION),
 				 errmsg("invalid response from primary server"),
 				 errdetail("Expected 1 tuple with 2 fields, got %d tuples with %d fields.",
-						   ntuples, nfields)));
-	}
+						   PQntuples(res), PQnfields(res))));
 	*filename = pstrdup(PQgetvalue(res, 0, 0));
 
 	*len = PQgetlength(res, 0, 1);
@@ -841,13 +823,10 @@ libpqrcv_receive(WalReceiverConn *conn, char **buffer,
 			return -1;
 		}
 		else
-		{
-			PQclear(res);
 			ereport(ERROR,
 					(errcode(ERRCODE_PROTOCOL_VIOLATION),
 					 errmsg("could not receive data from WAL stream: %s",
 							pchomp(PQerrorMessage(conn->streamConn)))));
-		}
 	}
 	if (rawlen < -1)
 		ereport(ERROR,
@@ -971,13 +950,10 @@ libpqrcv_create_slot(WalReceiverConn *conn, const char *slotname,
 	pfree(cmd.data);
 
 	if (PQresultStatus(res) != PGRES_TUPLES_OK)
-	{
-		PQclear(res);
 		ereport(ERROR,
 				(errcode(ERRCODE_PROTOCOL_VIOLATION),
 				 errmsg("could not create replication slot \"%s\": %s",
 						slotname, pchomp(PQerrorMessage(conn->streamConn)))));
-	}
 
 	if (lsn)
 		*lsn = DatumGetLSN(DirectFunctionCall1Coll(pg_lsn_in, InvalidOid,
diff --git a/src/backend/replication/logical/applyparallelworker.c b/src/backend/replication/logical/applyparallelworker.c
index d25085d351535..1fa931a74229d 100644
--- a/src/backend/replication/logical/applyparallelworker.c
+++ b/src/backend/replication/logical/applyparallelworker.c
@@ -441,7 +441,8 @@ pa_launch_parallel_worker(void)
 										MySubscription->name,
 										MyLogicalRepWorker->userid,
 										InvalidOid,
-										dsm_segment_handle(winfo->dsm_seg));
+										dsm_segment_handle(winfo->dsm_seg),
+										false);
 
 	if (launched)
 	{
diff --git a/src/backend/replication/logical/conflict.c b/src/backend/replication/logical/conflict.c
index 97c4e26b58654..2fd3e8bbda50b 100644
--- a/src/backend/replication/logical/conflict.c
+++ b/src/backend/replication/logical/conflict.c
@@ -29,6 +29,7 @@ static const char *const ConflictTypeNames[] = {
 	[CT_UPDATE_EXISTS] = "update_exists",
 	[CT_UPDATE_MISSING] = "update_missing",
 	[CT_DELETE_ORIGIN_DIFFERS] = "delete_origin_differs",
+	[CT_UPDATE_DELETED] = "update_deleted",
 	[CT_DELETE_MISSING] = "delete_missing",
 	[CT_MULTIPLE_UNIQUE_CONFLICTS] = "multiple_unique_conflicts"
 };
@@ -176,6 +177,7 @@ errcode_apply_conflict(ConflictType type)
 		case CT_UPDATE_ORIGIN_DIFFERS:
 		case CT_UPDATE_MISSING:
 		case CT_DELETE_ORIGIN_DIFFERS:
+		case CT_UPDATE_DELETED:
 		case CT_DELETE_MISSING:
 			return errcode(ERRCODE_T_R_SERIALIZATION_FAILURE);
 	}
@@ -261,6 +263,26 @@ errdetail_apply_conflict(EState *estate, ResultRelInfo *relinfo,
 
 			break;
 
+		case CT_UPDATE_DELETED:
+			if (localts)
+			{
+				if (localorigin == InvalidRepOriginId)
+					appendStringInfo(&err_detail, _("The row to be updated was deleted locally in transaction %u at %s."),
+									 localxmin, timestamptz_to_str(localts));
+				else if (replorigin_by_oid(localorigin, true, &origin_name))
+					appendStringInfo(&err_detail, _("The row to be updated was deleted by a different origin \"%s\" in transaction %u at %s."),
+									 origin_name, localxmin, timestamptz_to_str(localts));
+
+				/* The origin that modified this row has been removed. */
+				else
+					appendStringInfo(&err_detail, _("The row to be updated was deleted by a non-existent origin in transaction %u at %s."),
+									 localxmin, timestamptz_to_str(localts));
+			}
+			else
+				appendStringInfo(&err_detail, _("The row to be updated was deleted."));
+
+			break;
+
 		case CT_UPDATE_MISSING:
 			appendStringInfoString(&err_detail, _("Could not find the row to be updated."));
 			break;
diff --git a/src/backend/replication/logical/launcher.c b/src/backend/replication/logical/launcher.c
index 4aed0dfcebb24..37377f7eb636c 100644
--- a/src/backend/replication/logical/launcher.c
+++ b/src/backend/replication/logical/launcher.c
@@ -32,6 +32,7 @@
 #include "postmaster/interrupt.h"
 #include "replication/logicallauncher.h"
 #include "replication/origin.h"
+#include "replication/slot.h"
 #include "replication/walreceiver.h"
 #include "replication/worker_internal.h"
 #include "storage/ipc.h"
@@ -91,7 +92,6 @@ static dshash_table *last_start_times = NULL;
 static bool on_commit_launcher_wakeup = false;
 
 
-static void ApplyLauncherWakeup(void);
 static void logicalrep_launcher_onexit(int code, Datum arg);
 static void logicalrep_worker_onexit(int code, Datum arg);
 static void logicalrep_worker_detach(void);
@@ -100,6 +100,9 @@ static int	logicalrep_pa_worker_count(Oid subid);
 static void logicalrep_launcher_attach_dshmem(void);
 static void ApplyLauncherSetWorkerStartTime(Oid subid, TimestampTz start_time);
 static TimestampTz ApplyLauncherGetWorkerStartTime(Oid subid);
+static void compute_min_nonremovable_xid(LogicalRepWorker *worker, TransactionId *xmin);
+static bool acquire_conflict_slot_if_exists(void);
+static void advance_conflict_slot_xmin(TransactionId new_xmin);
 
 
 /*
@@ -148,6 +151,7 @@ get_subscription_list(void)
 		sub->owner = subform->subowner;
 		sub->enabled = subform->subenabled;
 		sub->name = pstrdup(NameStr(subform->subname));
+		sub->retaindeadtuples = subform->subretaindeadtuples;
 		/* We don't fill fields we are not interested in. */
 
 		res = lappend(res, sub);
@@ -309,7 +313,8 @@ logicalrep_workers_find(Oid subid, bool only_running, bool acquire_lock)
 bool
 logicalrep_worker_launch(LogicalRepWorkerType wtype,
 						 Oid dbid, Oid subid, const char *subname, Oid userid,
-						 Oid relid, dsm_handle subworker_dsm)
+						 Oid relid, dsm_handle subworker_dsm,
+						 bool retain_dead_tuples)
 {
 	BackgroundWorker bgw;
 	BackgroundWorkerHandle *bgw_handle;
@@ -328,10 +333,13 @@ logicalrep_worker_launch(LogicalRepWorkerType wtype,
 	 * - must be valid worker type
 	 * - tablesync workers are only ones to have relid
 	 * - parallel apply worker is the only kind of subworker
+	 * - The replication slot used in conflict detection is created when
+	 *   retain_dead_tuples is enabled
 	 */
 	Assert(wtype != WORKERTYPE_UNKNOWN);
 	Assert(is_tablesync_worker == OidIsValid(relid));
 	Assert(is_parallel_apply_worker == (subworker_dsm != DSM_HANDLE_INVALID));
+	Assert(!retain_dead_tuples || MyReplicationSlot);
 
 	ereport(DEBUG1,
 			(errmsg_internal("starting logical replication worker for subscription \"%s\"",
@@ -454,6 +462,9 @@ logicalrep_worker_launch(LogicalRepWorkerType wtype,
 	worker->stream_fileset = NULL;
 	worker->leader_pid = is_parallel_apply_worker ? MyProcPid : InvalidPid;
 	worker->parallel_apply = is_parallel_apply_worker;
+	worker->oldest_nonremovable_xid = retain_dead_tuples
+		? MyReplicationSlot->data.xmin
+		: InvalidTransactionId;
 	worker->last_lsn = InvalidXLogRecPtr;
 	TIMESTAMP_NOBEGIN(worker->last_send_time);
 	TIMESTAMP_NOBEGIN(worker->last_recv_time);
@@ -779,6 +790,8 @@ logicalrep_worker_detach(void)
 		}
 
 		LWLockRelease(LogicalRepWorkerLock);
+
+		list_free(workers);
 	}
 
 	/* Block concurrent access. */
@@ -1118,7 +1131,10 @@ ApplyLauncherWakeupAtCommit(void)
 		on_commit_launcher_wakeup = true;
 }
 
-static void
+/*
+ * Wakeup the launcher immediately.
+ */
+void
 ApplyLauncherWakeup(void)
 {
 	if (LogicalRepCtx->launcher_pid != 0)
@@ -1150,6 +1166,12 @@ ApplyLauncherMain(Datum main_arg)
 	 */
 	BackgroundWorkerInitializeConnection(NULL, NULL, 0);
 
+	/*
+	 * Acquire the conflict detection slot at startup to ensure it can be
+	 * dropped if no longer needed after a restart.
+	 */
+	acquire_conflict_slot_if_exists();
+
 	/* Enter main loop */
 	for (;;)
 	{
@@ -1159,6 +1181,9 @@ ApplyLauncherMain(Datum main_arg)
 		MemoryContext subctx;
 		MemoryContext oldctx;
 		long		wait_time = DEFAULT_NAPTIME_PER_CYCLE;
+		bool		can_advance_xmin = true;
+		bool		retain_dead_tuples = false;
+		TransactionId xmin = InvalidTransactionId;
 
 		CHECK_FOR_INTERRUPTS();
 
@@ -1168,7 +1193,14 @@ ApplyLauncherMain(Datum main_arg)
 									   ALLOCSET_DEFAULT_SIZES);
 		oldctx = MemoryContextSwitchTo(subctx);
 
-		/* Start any missing workers for enabled subscriptions. */
+		/*
+		 * Start any missing workers for enabled subscriptions.
+		 *
+		 * Also, during the iteration through all subscriptions, we compute
+		 * the minimum XID required to protect deleted tuples for conflict
+		 * detection if one of the subscription enables retain_dead_tuples
+		 * option.
+		 */
 		sublist = get_subscription_list();
 		foreach(lc, sublist)
 		{
@@ -1178,6 +1210,38 @@ ApplyLauncherMain(Datum main_arg)
 			TimestampTz now;
 			long		elapsed;
 
+			if (sub->retaindeadtuples)
+			{
+				retain_dead_tuples = true;
+
+				/*
+				 * Can't advance xmin of the slot unless all the subscriptions
+				 * with retain_dead_tuples are enabled. This is required to
+				 * ensure that we don't advance the xmin of
+				 * CONFLICT_DETECTION_SLOT if one of the subscriptions is not
+				 * enabled. Otherwise, we won't be able to detect conflicts
+				 * reliably for such a subscription even though it has set the
+				 * retain_dead_tuples option.
+				 */
+				can_advance_xmin &= sub->enabled;
+
+				/*
+				 * Create a replication slot to retain information necessary
+				 * for conflict detection such as dead tuples, commit
+				 * timestamps, and origins.
+				 *
+				 * The slot is created before starting the apply worker to
+				 * prevent it from unnecessarily maintaining its
+				 * oldest_nonremovable_xid.
+				 *
+				 * The slot is created even for a disabled subscription to
+				 * ensure that conflict-related information is available when
+				 * applying remote changes that occurred before the
+				 * subscription was enabled.
+				 */
+				CreateConflictDetectionSlot();
+			}
+
 			if (!sub->enabled)
 				continue;
 
@@ -1186,7 +1250,27 @@ ApplyLauncherMain(Datum main_arg)
 			LWLockRelease(LogicalRepWorkerLock);
 
 			if (w != NULL)
-				continue;		/* worker is running already */
+			{
+				/*
+				 * Compute the minimum xmin required to protect dead tuples
+				 * required for conflict detection among all running apply
+				 * workers that enables retain_dead_tuples.
+				 */
+				if (sub->retaindeadtuples && can_advance_xmin)
+					compute_min_nonremovable_xid(w, &xmin);
+
+				/* worker is running already */
+				continue;
+			}
+
+			/*
+			 * Can't advance xmin of the slot unless all the workers
+			 * corresponding to subscriptions with retain_dead_tuples are
+			 * running, disabling the further computation of the minimum
+			 * nonremovable xid.
+			 */
+			if (sub->retaindeadtuples)
+				can_advance_xmin = false;
 
 			/*
 			 * If the worker is eligible to start now, launch it.  Otherwise,
@@ -1210,7 +1294,8 @@ ApplyLauncherMain(Datum main_arg)
 				if (!logicalrep_worker_launch(WORKERTYPE_APPLY,
 											  sub->dbid, sub->oid, sub->name,
 											  sub->owner, InvalidOid,
-											  DSM_HANDLE_INVALID))
+											  DSM_HANDLE_INVALID,
+											  sub->retaindeadtuples))
 				{
 					/*
 					 * We get here either if we failed to launch a worker
@@ -1230,6 +1315,20 @@ ApplyLauncherMain(Datum main_arg)
 			}
 		}
 
+		/*
+		 * Drop the CONFLICT_DETECTION_SLOT slot if there is no subscription
+		 * that requires us to retain dead tuples. Otherwise, if required,
+		 * advance the slot's xmin to protect dead tuples required for the
+		 * conflict detection.
+		 */
+		if (MyReplicationSlot)
+		{
+			if (!retain_dead_tuples)
+				ReplicationSlotDropAcquired();
+			else if (can_advance_xmin)
+				advance_conflict_slot_xmin(xmin);
+		}
+
 		/* Switch back to original memory context. */
 		MemoryContextSwitchTo(oldctx);
 		/* Clean the temporary memory. */
@@ -1257,6 +1356,125 @@ ApplyLauncherMain(Datum main_arg)
 	/* Not reachable */
 }
 
+/*
+ * Determine the minimum non-removable transaction ID across all apply workers
+ * for subscriptions that have retain_dead_tuples enabled. Store the result
+ * in *xmin.
+ */
+static void
+compute_min_nonremovable_xid(LogicalRepWorker *worker, TransactionId *xmin)
+{
+	TransactionId nonremovable_xid;
+
+	Assert(worker != NULL);
+
+	/*
+	 * The replication slot for conflict detection must be created before the
+	 * worker starts.
+	 */
+	Assert(MyReplicationSlot);
+
+	SpinLockAcquire(&worker->relmutex);
+	nonremovable_xid = worker->oldest_nonremovable_xid;
+	SpinLockRelease(&worker->relmutex);
+
+	Assert(TransactionIdIsValid(nonremovable_xid));
+
+	if (!TransactionIdIsValid(*xmin) ||
+		TransactionIdPrecedes(nonremovable_xid, *xmin))
+		*xmin = nonremovable_xid;
+}
+
+/*
+ * Acquire the replication slot used to retain information for conflict
+ * detection, if it exists.
+ *
+ * Return true if successfully acquired, otherwise return false.
+ */
+static bool
+acquire_conflict_slot_if_exists(void)
+{
+	if (!SearchNamedReplicationSlot(CONFLICT_DETECTION_SLOT, true))
+		return false;
+
+	ReplicationSlotAcquire(CONFLICT_DETECTION_SLOT, true, false);
+	return true;
+}
+
+/*
+ * Advance the xmin the replication slot used to retain information required
+ * for conflict detection.
+ */
+static void
+advance_conflict_slot_xmin(TransactionId new_xmin)
+{
+	Assert(MyReplicationSlot);
+	Assert(TransactionIdIsValid(new_xmin));
+	Assert(TransactionIdPrecedesOrEquals(MyReplicationSlot->data.xmin, new_xmin));
+
+	/* Return if the xmin value of the slot cannot be advanced */
+	if (TransactionIdEquals(MyReplicationSlot->data.xmin, new_xmin))
+		return;
+
+	SpinLockAcquire(&MyReplicationSlot->mutex);
+	MyReplicationSlot->effective_xmin = new_xmin;
+	MyReplicationSlot->data.xmin = new_xmin;
+	SpinLockRelease(&MyReplicationSlot->mutex);
+
+	elog(DEBUG1, "updated xmin: %u", MyReplicationSlot->data.xmin);
+
+	ReplicationSlotMarkDirty();
+	ReplicationSlotsComputeRequiredXmin(false);
+
+	/*
+	 * Like PhysicalConfirmReceivedLocation(), do not save slot information
+	 * each time. This is acceptable because all concurrent transactions on
+	 * the publisher that require the data preceding the slot's xmin should
+	 * have already been applied and flushed on the subscriber before the xmin
+	 * is advanced. So, even if the slot's xmin regresses after a restart, it
+	 * will be advanced again in the next cycle. Therefore, no data required
+	 * for conflict detection will be prematurely removed.
+	 */
+	return;
+}
+
+/*
+ * Create and acquire the replication slot used to retain information for
+ * conflict detection, if not yet.
+ */
+void
+CreateConflictDetectionSlot(void)
+{
+	TransactionId xmin_horizon;
+
+	/* Exit early, if the replication slot is already created and acquired */
+	if (MyReplicationSlot)
+		return;
+
+	ereport(LOG,
+			errmsg("creating replication conflict detection slot"));
+
+	ReplicationSlotCreate(CONFLICT_DETECTION_SLOT, false, RS_PERSISTENT, false,
+						  false, false);
+
+	LWLockAcquire(ProcArrayLock, LW_EXCLUSIVE);
+
+	xmin_horizon = GetOldestSafeDecodingTransactionId(false);
+
+	SpinLockAcquire(&MyReplicationSlot->mutex);
+	MyReplicationSlot->effective_xmin = xmin_horizon;
+	MyReplicationSlot->data.xmin = xmin_horizon;
+	SpinLockRelease(&MyReplicationSlot->mutex);
+
+	ReplicationSlotsComputeRequiredXmin(true);
+
+	LWLockRelease(ProcArrayLock);
+
+	/* Write this slot to disk */
+	ReplicationSlotMarkDirty();
+	ReplicationSlotSave();
+}
+
 /*
  * Is current process the logical replication launcher?
  */
diff --git a/src/backend/replication/logical/logical.c b/src/backend/replication/logical/logical.c
index f1eb798f3e97a..7e363a7c05b4f 100644
--- a/src/backend/replication/logical/logical.c
+++ b/src/backend/replication/logical/logical.c
@@ -567,7 +567,7 @@ CreateDecodingContext(XLogRecPtr start_lsn,
 		 * kinds of client errors; so the client may wish to check that
 		 * confirmed_flush_lsn matches its expectations.
 		 */
-		elog(LOG, "%X/%X has been already streamed, forwarding to %X/%X",
+		elog(LOG, "%X/%08X has been already streamed, forwarding to %X/%08X",
 			 LSN_FORMAT_ARGS(start_lsn),
 			 LSN_FORMAT_ARGS(slot->data.confirmed_flush));
 
@@ -610,7 +610,7 @@ CreateDecodingContext(XLogRecPtr start_lsn,
 	ereport(LOG,
 			(errmsg("starting logical decoding for slot \"%s\"",
 					NameStr(slot->data.name)),
-			 errdetail("Streaming transactions committing after %X/%X, reading WAL from %X/%X.",
+			 errdetail("Streaming transactions committing after %X/%08X, reading WAL from %X/%08X.",
 					   LSN_FORMAT_ARGS(slot->data.confirmed_flush),
 					   LSN_FORMAT_ARGS(slot->data.restart_lsn))));
 
@@ -637,7 +637,7 @@ DecodingContextFindStartpoint(LogicalDecodingContext *ctx)
 	/* Initialize from where to start reading WAL. */
 	XLogBeginRead(ctx->reader, slot->data.restart_lsn);
 
-	elog(DEBUG1, "searching for logical decoding starting point, starting at %X/%X",
+	elog(DEBUG1, "searching for logical decoding starting point, starting at %X/%08X",
 		 LSN_FORMAT_ARGS(slot->data.restart_lsn));
 
 	/* Wait for a consistent starting point */
@@ -758,7 +758,7 @@ output_plugin_error_callback(void *arg)
 
 	/* not all callbacks have an associated LSN  */
 	if (state->report_location != InvalidXLogRecPtr)
-		errcontext("slot \"%s\", output plugin \"%s\", in the %s callback, associated LSN %X/%X",
+		errcontext("slot \"%s\", output plugin \"%s\", in the %s callback, associated LSN %X/%08X",
 				   NameStr(state->ctx->slot->data.name),
 				   NameStr(state->ctx->slot->data.plugin),
 				   state->callback_name,
@@ -1725,7 +1725,7 @@ LogicalIncreaseXminForSlot(XLogRecPtr current_lsn, TransactionId xmin)
 	SpinLockRelease(&slot->mutex);
 
 	if (got_new_xmin)
-		elog(DEBUG1, "got new catalog xmin %u at %X/%X", xmin,
+		elog(DEBUG1, "got new catalog xmin %u at %X/%08X", xmin,
 			 LSN_FORMAT_ARGS(current_lsn));
 
 	/* candidate already valid with the current flush position, apply */
@@ -1785,7 +1785,7 @@ LogicalIncreaseRestartDecodingForSlot(XLogRecPtr current_lsn, XLogRecPtr restart
 		slot->candidate_restart_lsn = restart_lsn;
 		SpinLockRelease(&slot->mutex);
 
-		elog(DEBUG1, "got new restart lsn %X/%X at %X/%X",
+		elog(DEBUG1, "got new restart lsn %X/%08X at %X/%08X",
 			 LSN_FORMAT_ARGS(restart_lsn),
 			 LSN_FORMAT_ARGS(current_lsn));
 	}
@@ -1800,7 +1800,7 @@ LogicalIncreaseRestartDecodingForSlot(XLogRecPtr current_lsn, XLogRecPtr restart
 		confirmed_flush = slot->data.confirmed_flush;
 		SpinLockRelease(&slot->mutex);
 
-		elog(DEBUG1, "failed to increase restart lsn: proposed %X/%X, after %X/%X, current candidate %X/%X, current after %X/%X, flushed up to %X/%X",
+		elog(DEBUG1, "failed to increase restart lsn: proposed %X/%08X, after %X/%08X, current candidate %X/%08X, current after %X/%08X, flushed up to %X/%08X",
 			 LSN_FORMAT_ARGS(restart_lsn),
 			 LSN_FORMAT_ARGS(current_lsn),
 			 LSN_FORMAT_ARGS(candidate_restart_lsn),
diff --git a/src/backend/replication/logical/origin.c b/src/backend/replication/logical/origin.c
index a17bacf88e7f3..87f10e50dcc4d 100644
--- a/src/backend/replication/logical/origin.c
+++ b/src/backend/replication/logical/origin.c
@@ -826,9 +826,9 @@ StartupReplicationOrigin(void)
 		last_state++;
 
 		ereport(LOG,
-				(errmsg("recovered replication state of node %d to %X/%X",
-						disk_state.roident,
-						LSN_FORMAT_ARGS(disk_state.remote_lsn))));
+				errmsg("recovered replication state of node %d to %X/%08X",
+					   disk_state.roident,
+					   LSN_FORMAT_ARGS(disk_state.remote_lsn)));
 	}
 
 	/* now check checksum */
diff --git a/src/backend/replication/logical/proto.c b/src/backend/replication/logical/proto.c
index 1a352b542dc56..1b3d9eb49dd70 100644
--- a/src/backend/replication/logical/proto.c
+++ b/src/backend/replication/logical/proto.c
@@ -809,7 +809,7 @@ logicalrep_write_tuple(StringInfo out, Relation rel, TupleTableSlot *slot,
 			continue;
 		}
 
-		if (att->attlen == -1 && VARATT_IS_EXTERNAL_ONDISK(values[i]))
+		if (att->attlen == -1 && VARATT_IS_EXTERNAL_ONDISK(DatumGetPointer(values[i])))
 		{
 			/*
 			 * Unchanged toasted datum.  (Note that we don't promise to detect
diff --git a/src/backend/replication/logical/reorderbuffer.c b/src/backend/replication/logical/reorderbuffer.c
index c4299c76fb16b..34cf05668ae84 100644
--- a/src/backend/replication/logical/reorderbuffer.c
+++ b/src/backend/replication/logical/reorderbuffer.c
@@ -1415,7 +1415,7 @@ ReorderBufferIterTXNNext(ReorderBuffer *rb, ReorderBufferIterTXNState *state)
 	int32		off;
 
 	/* nothing there anymore */
-	if (state->heap->bh_size == 0)
+	if (binaryheap_empty(state->heap))
 		return NULL;
 
 	off = DatumGetInt32(binaryheap_first(state->heap));
@@ -2599,7 +2599,7 @@ ReorderBufferProcessTXN(ReorderBuffer *rb, ReorderBufferTXN *txn,
 
 			if (++changes_count >= CHANGES_THRESHOLD)
 			{
-				rb->update_progress_txn(rb, txn, change->lsn);
+				rb->update_progress_txn(rb, txn, prev_lsn);
 				changes_count = 0;
 			}
 		}
@@ -4917,7 +4917,7 @@ StartupReorderBuffer(void)
 			continue;
 
 		/* if it cannot be a slot, skip the directory */
-		if (!ReplicationSlotValidateName(logical_de->d_name, DEBUG2))
+		if (!ReplicationSlotValidateName(logical_de->d_name, true, DEBUG2))
 			continue;
 
 		/*
diff --git a/src/backend/replication/logical/slotsync.c b/src/backend/replication/logical/slotsync.c
index 3ec3abfa3da60..3773844011358 100644
--- a/src/backend/replication/logical/slotsync.c
+++ b/src/backend/replication/logical/slotsync.c
@@ -213,7 +213,7 @@ update_local_synced_slot(RemoteSlot *remote_slot, Oid remote_dbid,
 		ereport(slot->data.persistency == RS_TEMPORARY ? LOG : DEBUG1,
 				errmsg("could not synchronize replication slot \"%s\"",
 					   remote_slot->name),
-				errdetail("Synchronization could lead to data loss, because the remote slot needs WAL at LSN %X/%X and catalog xmin %u, but the standby has LSN %X/%X and catalog xmin %u.",
+				errdetail("Synchronization could lead to data loss, because the remote slot needs WAL at LSN %X/%08X and catalog xmin %u, but the standby has LSN %X/%08X and catalog xmin %u.",
 						  LSN_FORMAT_ARGS(remote_slot->restart_lsn),
 						  remote_slot->catalog_xmin,
 						  LSN_FORMAT_ARGS(slot->data.restart_lsn),
@@ -275,7 +275,7 @@ update_local_synced_slot(RemoteSlot *remote_slot, Oid remote_dbid,
 				ereport(ERROR,
 						errmsg_internal("synchronized confirmed_flush for slot \"%s\" differs from remote slot",
 										remote_slot->name),
-						errdetail_internal("Remote slot has LSN %X/%X but local slot has LSN %X/%X.",
+						errdetail_internal("Remote slot has LSN %X/%08X but local slot has LSN %X/%08X.",
 										   LSN_FORMAT_ARGS(remote_slot->confirmed_lsn),
 										   LSN_FORMAT_ARGS(slot->data.confirmed_flush)));
 		}
@@ -593,7 +593,7 @@ update_and_persist_local_synced_slot(RemoteSlot *remote_slot, Oid remote_dbid)
 	{
 		ereport(LOG,
 				errmsg("could not synchronize replication slot \"%s\"", remote_slot->name),
-				errdetail("Synchronization could lead to data loss, because the standby could not build a consistent snapshot to decode WALs at LSN %X/%X.",
+				errdetail("Synchronization could lead to data loss, because the standby could not build a consistent snapshot to decode WALs at LSN %X/%08X.",
 						  LSN_FORMAT_ARGS(slot->data.restart_lsn)));
 
 		return false;
@@ -642,7 +642,7 @@ synchronize_one_slot(RemoteSlot *remote_slot, Oid remote_dbid)
 		ereport(AmLogicalSlotSyncWorkerProcess() ? LOG : ERROR,
 				errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
 				errmsg("skipping slot synchronization because the received slot sync"
-					   " LSN %X/%X for slot \"%s\" is ahead of the standby position %X/%X",
+					   " LSN %X/%08X for slot \"%s\" is ahead of the standby position %X/%08X",
 					   LSN_FORMAT_ARGS(remote_slot->confirmed_lsn),
 					   remote_slot->name,
 					   LSN_FORMAT_ARGS(latestFlushPtr)));
@@ -733,7 +733,7 @@ synchronize_one_slot(RemoteSlot *remote_slot, Oid remote_dbid)
 				ereport(ERROR,
 						errmsg_internal("cannot synchronize local slot \"%s\"",
 										remote_slot->name),
-						errdetail_internal("Local slot's start streaming location LSN(%X/%X) is ahead of remote slot's LSN(%X/%X).",
+						errdetail_internal("Local slot's start streaming location LSN(%X/%08X) is ahead of remote slot's LSN(%X/%08X).",
 										   LSN_FORMAT_ARGS(slot->data.confirmed_flush),
 										   LSN_FORMAT_ARGS(remote_slot->confirmed_lsn)));
 
@@ -1059,14 +1059,14 @@ ValidateSlotSyncParams(int elevel)
 {
 	/*
 	 * Logical slot sync/creation requires wal_level >= logical.
-	 *
-	 * Since altering the wal_level requires a server restart, so error out in
-	 * this case regardless of elevel provided by caller.
 	 */
 	if (wal_level < WAL_LEVEL_LOGICAL)
-		ereport(ERROR,
+	{
+		ereport(elevel,
 				errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				errmsg("replication slot synchronization requires \"wal_level\" >= \"logical\""));
+		return false;
+	}
 
 	/*
 	 * A physical replication slot(primary_slot_name) is required on the
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index adf18c397db43..8532bfd27e53f 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -774,7 +774,7 @@ SnapBuildDistributeSnapshotAndInval(SnapBuild *builder, XLogRecPtr lsn, Transact
 		if (rbtxn_is_prepared(txn))
 			continue;
 
-		elog(DEBUG2, "adding a new snapshot and invalidations to %u at %X/%X",
+		elog(DEBUG2, "adding a new snapshot and invalidations to %u at %X/%08X",
 			 txn->xid, LSN_FORMAT_ARGS(lsn));
 
 		/*
@@ -1271,10 +1271,10 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 									builder->initial_xmin_horizon))
 	{
 		ereport(DEBUG1,
-				(errmsg_internal("skipping snapshot at %X/%X while building logical decoding snapshot, xmin horizon too low",
-								 LSN_FORMAT_ARGS(lsn)),
-				 errdetail_internal("initial xmin horizon of %u vs the snapshot's %u",
-									builder->initial_xmin_horizon, running->oldestRunningXid)));
+				errmsg_internal("skipping snapshot at %X/%08X while building logical decoding snapshot, xmin horizon too low",
+								LSN_FORMAT_ARGS(lsn)),
+				errdetail_internal("initial xmin horizon of %u vs the snapshot's %u",
+								   builder->initial_xmin_horizon, running->oldestRunningXid));
 
 
 		SnapBuildWaitSnapshot(running, builder->initial_xmin_horizon);
@@ -1310,9 +1310,9 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->next_phase_at = InvalidTransactionId;
 
 		ereport(LOG,
-				(errmsg("logical decoding found consistent point at %X/%X",
-						LSN_FORMAT_ARGS(lsn)),
-				 errdetail("There are no running transactions.")));
+				errmsg("logical decoding found consistent point at %X/%08X",
+					   LSN_FORMAT_ARGS(lsn)),
+				errdetail("There are no running transactions."));
 
 		return false;
 	}
@@ -1359,10 +1359,10 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		Assert(TransactionIdIsNormal(builder->xmax));
 
 		ereport(LOG,
-				(errmsg("logical decoding found initial starting point at %X/%X",
-						LSN_FORMAT_ARGS(lsn)),
-				 errdetail("Waiting for transactions (approximately %d) older than %u to end.",
-						   running->xcnt, running->nextXid)));
+				errmsg("logical decoding found initial starting point at %X/%08X",
+					   LSN_FORMAT_ARGS(lsn)),
+				errdetail("Waiting for transactions (approximately %d) older than %u to end.",
+						  running->xcnt, running->nextXid));
 
 		SnapBuildWaitSnapshot(running, running->nextXid);
 	}
@@ -1383,10 +1383,10 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->next_phase_at = running->nextXid;
 
 		ereport(LOG,
-				(errmsg("logical decoding found initial consistent point at %X/%X",
-						LSN_FORMAT_ARGS(lsn)),
-				 errdetail("Waiting for transactions (approximately %d) older than %u to end.",
-						   running->xcnt, running->nextXid)));
+				errmsg("logical decoding found initial consistent point at %X/%08X",
+					   LSN_FORMAT_ARGS(lsn)),
+				errdetail("Waiting for transactions (approximately %d) older than %u to end.",
+						  running->xcnt, running->nextXid));
 
 		SnapBuildWaitSnapshot(running, running->nextXid);
 	}
@@ -1407,9 +1407,9 @@ SnapBuildFindSnapshot(SnapBuild *builder, XLogRecPtr lsn, xl_running_xacts *runn
 		builder->next_phase_at = InvalidTransactionId;
 
 		ereport(LOG,
-				(errmsg("logical decoding found consistent point at %X/%X",
-						LSN_FORMAT_ARGS(lsn)),
-				 errdetail("There are no old transactions anymore.")));
+				errmsg("logical decoding found consistent point at %X/%08X",
+					   LSN_FORMAT_ARGS(lsn)),
+				errdetail("There are no old transactions anymore."));
 	}
 
 	/*
@@ -1913,9 +1913,9 @@ SnapBuildRestore(SnapBuild *builder, XLogRecPtr lsn)
 	Assert(builder->state == SNAPBUILD_CONSISTENT);
 
 	ereport(LOG,
-			(errmsg("logical decoding found consistent point at %X/%X",
-					LSN_FORMAT_ARGS(lsn)),
-			 errdetail("Logical decoding will begin using saved snapshot.")));
+			errmsg("logical decoding found consistent point at %X/%08X",
+				   LSN_FORMAT_ARGS(lsn)),
+			errdetail("Logical decoding will begin using saved snapshot."));
 	return true;
 
 snapshot_not_interesting:
@@ -2061,7 +2061,7 @@ SnapBuildSnapshotExists(XLogRecPtr lsn)
 	int			ret;
 	struct stat stat_buf;
 
-	sprintf(path, "%s/%X-%X.snap",
+	sprintf(path, "%s/%08X-%08X.snap",
 			PG_LOGICAL_SNAPSHOTS_DIR,
 			LSN_FORMAT_ARGS(lsn));
 
diff --git a/src/backend/replication/logical/tablesync.c b/src/backend/replication/logical/tablesync.c
index c90f23ee5b0b2..d3356bc84ee0c 100644
--- a/src/backend/replication/logical/tablesync.c
+++ b/src/backend/replication/logical/tablesync.c
@@ -316,7 +316,8 @@ process_syncing_tables_for_sync(XLogRecPtr current_lsn)
 		UpdateSubscriptionRelState(MyLogicalRepWorker->subid,
 								   MyLogicalRepWorker->relid,
 								   MyLogicalRepWorker->relstate,
-								   MyLogicalRepWorker->relstate_lsn);
+								   MyLogicalRepWorker->relstate_lsn,
+								   false);
 
 		/*
 		 * End streaming so that LogRepWorkerWalRcvConn can be used to drop
@@ -425,6 +426,7 @@ process_syncing_tables_for_apply(XLogRecPtr current_lsn)
 	ListCell   *lc;
 	bool		started_tx = false;
 	bool		should_exit = false;
+	Relation	rel = NULL;
 
 	Assert(!IsTransactionState());
 
@@ -492,7 +494,17 @@ process_syncing_tables_for_apply(XLogRecPtr current_lsn)
 				 * worker to remove the origin tracking as if there is any
 				 * error while dropping we won't restart it to drop the
 				 * origin. So passing missing_ok = true.
+				 *
+				 * Lock the subscription and origin in the same order as we
+				 * are doing during DDL commands to avoid deadlocks. See
+				 * AlterSubscription_refresh.
 				 */
+				LockSharedObject(SubscriptionRelationId, MyLogicalRepWorker->subid,
+								 0, AccessShareLock);
+
+				if (!rel)
+					rel = table_open(SubscriptionRelRelationId, RowExclusiveLock);
+
 				ReplicationOriginNameForLogicalRep(MyLogicalRepWorker->subid,
 												   rstate->relid,
 												   originname,
@@ -504,7 +516,7 @@ process_syncing_tables_for_apply(XLogRecPtr current_lsn)
 				 */
 				UpdateSubscriptionRelState(MyLogicalRepWorker->subid,
 										   rstate->relid, rstate->state,
-										   rstate->lsn);
+										   rstate->lsn, true);
 			}
 		}
 		else
@@ -555,7 +567,14 @@ process_syncing_tables_for_apply(XLogRecPtr current_lsn)
 						 * This is required to avoid any undetected deadlocks
 						 * due to any existing lock as deadlock detector won't
 						 * be able to detect the waits on the latch.
+						 *
+						 * Also close any tables prior to the commit.
 						 */
+						if (rel)
+						{
+							table_close(rel, NoLock);
+							rel = NULL;
+						}
 						CommitTransactionCommand();
 						pgstat_report_stat(false);
 					}
@@ -615,13 +634,19 @@ process_syncing_tables_for_apply(XLogRecPtr current_lsn)
 														MySubscription->name,
 														MyLogicalRepWorker->userid,
 														rstate->relid,
-														DSM_HANDLE_INVALID);
+														DSM_HANDLE_INVALID,
+														false);
 					}
 				}
 			}
 		}
 	}
 
+	/* Close table if opened */
+	if (rel)
+		table_close(rel, NoLock);
+
+
 	if (started_tx)
 	{
 		/*
@@ -1413,7 +1438,8 @@ LogicalRepSyncTableStart(XLogRecPtr *origin_startpos)
 	UpdateSubscriptionRelState(MyLogicalRepWorker->subid,
 							   MyLogicalRepWorker->relid,
 							   MyLogicalRepWorker->relstate,
-							   MyLogicalRepWorker->relstate_lsn);
+							   MyLogicalRepWorker->relstate_lsn,
+							   false);
 	CommitTransactionCommand();
 	pgstat_report_stat(true);
 
@@ -1546,14 +1572,15 @@ LogicalRepSyncTableStart(XLogRecPtr *origin_startpos)
 	UpdateSubscriptionRelState(MyLogicalRepWorker->subid,
 							   MyLogicalRepWorker->relid,
 							   SUBREL_STATE_FINISHEDCOPY,
-							   MyLogicalRepWorker->relstate_lsn);
+							   MyLogicalRepWorker->relstate_lsn,
+							   false);
 
 	CommitTransactionCommand();
 
 copy_table_done:
 
 	elog(DEBUG1,
-		 "LogicalRepSyncTableStart: '%s' origin_startpos lsn %X/%X",
+		 "LogicalRepSyncTableStart: '%s' origin_startpos lsn %X/%08X",
 		 originname, LSN_FORMAT_ARGS(*origin_startpos));
 
 	/*
diff --git a/src/backend/replication/logical/worker.c b/src/backend/replication/logical/worker.c
index fd11805a44cf9..89e241c839280 100644
--- a/src/backend/replication/logical/worker.c
+++ b/src/backend/replication/logical/worker.c
@@ -132,6 +132,96 @@
  * failover = true when creating the subscription. Enabling failover allows us
  * to smoothly transition to the promoted standby, ensuring that we can
  * subscribe to the new primary without losing any data.
+ *
+ * RETAIN DEAD TUPLES
+ * ----------------------
+ * Each apply worker that enabled retain_dead_tuples option maintains a
+ * non-removable transaction ID (oldest_nonremovable_xid) in shared memory to
+ * prevent dead rows from being removed prematurely when the apply worker still
+ * needs them to detect update_deleted conflicts. Additionally, this helps to
+ * retain the required commit_ts module information, which further helps to
+ * detect update_origin_differs and delete_origin_differs conflicts reliably, as
+ * otherwise, vacuum freeze could remove the required information.
+ *
+ * The logical replication launcher manages an internal replication slot named
+ * "pg_conflict_detection". It asynchronously aggregates the non-removable
+ * transaction ID from all apply workers to determine the appropriate xmin for
+ * the slot, thereby retaining necessary tuples.
+ *
+ * The non-removable transaction ID in the apply worker is advanced to the
+ * oldest running transaction ID once all concurrent transactions on the
+ * publisher have been applied and flushed locally. The process involves:
+ *
+ * - RDT_GET_CANDIDATE_XID:
+ *   Call GetOldestActiveTransactionId() to take oldestRunningXid as the
+ *   candidate xid.
+ *
+ * - RDT_REQUEST_PUBLISHER_STATUS:
+ *   Send a message to the walsender requesting the publisher status, which
+ *   includes the latest WAL write position and information about transactions
+ *   that are in the commit phase.
+ *
+ * - RDT_WAIT_FOR_PUBLISHER_STATUS:
+ *   Wait for the status from the walsender. After receiving the first status,
+ *   do not proceed if there are concurrent remote transactions that are still
+ *   in the commit phase. These transactions might have been assigned an
+ *   earlier commit timestamp but have not yet written the commit WAL record.
+ *   Continue to request the publisher status (RDT_REQUEST_PUBLISHER_STATUS)
+ *   until all these transactions have completed.
+ *
+ * - RDT_WAIT_FOR_LOCAL_FLUSH:
+ *   Advance the non-removable transaction ID if the current flush location has
+ *   reached or surpassed the last received WAL position.
+ *
+ * The overall state progression is: GET_CANDIDATE_XID ->
+ * REQUEST_PUBLISHER_STATUS -> WAIT_FOR_PUBLISHER_STATUS -> (loop to
+ * REQUEST_PUBLISHER_STATUS till concurrent remote transactions end) ->
+ * WAIT_FOR_LOCAL_FLUSH -> loop back to GET_CANDIDATE_XID.
+ *
+ * Retaining the dead tuples for this period is sufficient for ensuring
+ * eventual consistency using last-update-wins strategy, as dead tuples are
+ * useful for detecting conflicts only during the application of concurrent
+ * transactions from remote nodes. After applying and flushing all remote
+ * transactions that occurred concurrently with the tuple DELETE, any
+ * subsequent UPDATE from a remote node should have a later timestamp. In such
+ * cases, it is acceptable to detect an update_missing scenario and convert the
+ * UPDATE to an INSERT when applying it. But, for concurrent remote
+ * transactions with earlier timestamps than the DELETE, detecting
+ * update_deleted is necessary, as the UPDATEs in remote transactions should be
+ * ignored if their timestamp is earlier than that of the dead tuples.
+ *
+ * Note that advancing the non-removable transaction ID is not supported if the
+ * publisher is also a physical standby. This is because the logical walsender
+ * on the standby can only get the WAL replay position but there may be more
+ * WALs that are being replicated from the primary and those WALs could have
+ * earlier commit timestamp.
+ *
+ * Similarly, when the publisher has subscribed to another publisher,
+ * information necessary for conflict detection cannot be retained for
+ * changes from origins other than the publisher. This is because publisher
+ * lacks the information on concurrent transactions of other publishers to
+ * which it subscribes. As the information on concurrent transactions is
+ * unavailable beyond subscriber's immediate publishers, the non-removable
+ * transaction ID might be advanced prematurely before changes from other
+ * origins have been fully applied.
+ *
+ * XXX Retaining information for changes from other origins might be possible
+ * by requesting the subscription on that origin to enable retain_dead_tuples
+ * and fetching the conflict detection slot.xmin along with the publisher's
+ * status. In the RDT_WAIT_FOR_PUBLISHER_STATUS phase, the apply worker could
+ * wait for the remote slot's xmin to reach the oldest active transaction ID,
+ * ensuring that all transactions from other origins have been applied on the
+ * publisher, thereby getting the latest WAL position that includes all
+ * concurrent changes. However, this approach may impact performance, so it
+ * might not worth the effort.
+ *
+ * XXX It seems feasible to get the latest commit's WAL location from the
+ * publisher and wait till that is applied. However, we can't do that
+ * because commit timestamps can regress as a commit with a later LSN is not
+ * guaranteed to have a later timestamp than those with earlier LSNs. Having
+ * said that, even if that is possible, it won't improve performance much as
+ * the apply always lag and moves slowly as compared with the transactions
+ * on the publisher.
  *-------------------------------------------------------------------------
  */
 
@@ -140,6 +230,7 @@
 #include <sys/stat.h>
 #include <unistd.h>
 
+#include "access/commit_ts.h"
 #include "access/table.h"
 #include "access/tableam.h"
 #include "access/twophase.h"
@@ -148,6 +239,7 @@
 #include "catalog/pg_inherits.h"
 #include "catalog/pg_subscription.h"
 #include "catalog/pg_subscription_rel.h"
+#include "commands/subscriptioncmds.h"
 #include "commands/tablecmds.h"
 #include "commands/trigger.h"
 #include "executor/executor.h"
@@ -166,12 +258,14 @@
 #include "replication/logicalrelation.h"
 #include "replication/logicalworker.h"
 #include "replication/origin.h"
+#include "replication/slot.h"
 #include "replication/walreceiver.h"
 #include "replication/worker_internal.h"
 #include "rewrite/rewriteHandler.h"
 #include "storage/buffile.h"
 #include "storage/ipc.h"
 #include "storage/lmgr.h"
+#include "storage/procarray.h"
 #include "tcop/tcopprot.h"
 #include "utils/acl.h"
 #include "utils/dynahash.h"
@@ -268,6 +362,78 @@ typedef enum
 	TRANS_PARALLEL_APPLY,
 } TransApplyAction;
 
+/*
+ * The phases involved in advancing the non-removable transaction ID.
+ *
+ * See comments atop worker.c for details of the transition between these
+ * phases.
+ */
+typedef enum
+{
+	RDT_GET_CANDIDATE_XID,
+	RDT_REQUEST_PUBLISHER_STATUS,
+	RDT_WAIT_FOR_PUBLISHER_STATUS,
+	RDT_WAIT_FOR_LOCAL_FLUSH
+} RetainDeadTuplesPhase;
+
+/*
+ * Critical information for managing phase transitions within the
+ * RetainDeadTuplesPhase.
+ */
+typedef struct RetainDeadTuplesData
+{
+	RetainDeadTuplesPhase phase;	/* current phase */
+	XLogRecPtr	remote_lsn;		/* WAL write position on the publisher */
+
+	/*
+	 * Oldest transaction ID that was in the commit phase on the publisher.
+	 * Use FullTransactionId to prevent issues with transaction ID wraparound,
+	 * where a new remote_oldestxid could falsely appear to originate from the
+	 * past and block advancement.
+	 */
+	FullTransactionId remote_oldestxid;
+
+	/*
+	 * Next transaction ID to be assigned on the publisher. Use
+	 * FullTransactionId for consistency and to allow straightforward
+	 * comparisons with remote_oldestxid.
+	 */
+	FullTransactionId remote_nextxid;
+
+	TimestampTz reply_time;		/* when the publisher responds with status */
+
+	/*
+	 * Publisher transaction ID that must be awaited to complete before
+	 * entering the final phase (RDT_WAIT_FOR_LOCAL_FLUSH). Use
+	 * FullTransactionId for the same reason as remote_nextxid.
+	 */
+	FullTransactionId remote_wait_for;
+
+	TransactionId candidate_xid;	/* candidate for the non-removable
+									 * transaction ID */
+	TimestampTz flushpos_update_time;	/* when the remote flush position was
+										 * updated in final phase
+										 * (RDT_WAIT_FOR_LOCAL_FLUSH) */
+
+	/*
+	 * The following fields are used to determine the timing for the next
+	 * round of transaction ID advancement.
+	 */
+	TimestampTz last_recv_time; /* when the last message was received */
+	TimestampTz candidate_xid_time; /* when the candidate_xid is decided */
+	int			xid_advance_interval;	/* how much time (ms) to wait before
+										 * attempting to advance the
+										 * non-removable transaction ID */
+} RetainDeadTuplesData;
+
+/*
+ * The minimum (100ms) and maximum (3 minutes) intervals for advancing
+ * non-removable transaction IDs. The maximum interval is a bit arbitrary but
+ * is sufficient to not cause any undue network traffic.
+ */
+#define MIN_XID_ADVANCE_INTERVAL 100
+#define MAX_XID_ADVANCE_INTERVAL 180000
+
 /* errcontext tracker */
 static ApplyErrorCallbackArg apply_error_callback_arg =
 {
@@ -332,6 +498,13 @@ static XLogRecPtr skip_xact_finish_lsn = InvalidXLogRecPtr;
 /* BufFile handle of the current streaming file */
 static BufFile *stream_fd = NULL;
 
+/*
+ * The remote WAL position that has been applied and flushed locally. We record
+ * and use this information both while sending feedback to the server and
+ * advancing oldest_nonremovable_xid.
+ */
+static XLogRecPtr last_flushpos = InvalidXLogRecPtr;
+
 typedef struct SubXactInfo
 {
 	TransactionId xid;			/* XID of the subxact */
@@ -372,6 +545,19 @@ static void stream_close_file(void);
 
 static void send_feedback(XLogRecPtr recvpos, bool force, bool requestReply);
 
+static void maybe_advance_nonremovable_xid(RetainDeadTuplesData *rdt_data,
+										   bool status_received);
+static bool can_advance_nonremovable_xid(RetainDeadTuplesData *rdt_data);
+static void process_rdt_phase_transition(RetainDeadTuplesData *rdt_data,
+										 bool status_received);
+static void get_candidate_xid(RetainDeadTuplesData *rdt_data);
+static void request_publisher_status(RetainDeadTuplesData *rdt_data);
+static void wait_for_publisher_status(RetainDeadTuplesData *rdt_data,
+									  bool status_received);
+static void wait_for_local_flush(RetainDeadTuplesData *rdt_data);
+static void adjust_xid_advance_interval(RetainDeadTuplesData *rdt_data,
+										bool new_xid_found);
+
 static void apply_handle_commit_internal(LogicalRepCommitData *commit_data);
 static void apply_handle_insert_internal(ApplyExecutionData *edata,
 										 ResultRelInfo *relinfo,
@@ -390,6 +576,12 @@ static bool FindReplTupleInLocalRel(ApplyExecutionData *edata, Relation localrel
 									Oid localidxoid,
 									TupleTableSlot *remoteslot,
 									TupleTableSlot **localslot);
+static bool FindDeletedTupleInLocalRel(Relation localrel,
+									   Oid localidxoid,
+									   TupleTableSlot *remoteslot,
+									   TransactionId *delete_xid,
+									   RepOriginId *delete_origin,
+									   TimestampTz *delete_time);
 static void apply_handle_tuple_routing(ApplyExecutionData *edata,
 									   TupleTableSlot *remoteslot,
 									   LogicalRepTupleData *newtup,
@@ -1016,7 +1208,7 @@ apply_handle_commit(StringInfo s)
 	if (commit_data.commit_lsn != remote_final_lsn)
 		ereport(ERROR,
 				(errcode(ERRCODE_PROTOCOL_VIOLATION),
-				 errmsg_internal("incorrect commit LSN %X/%X in commit message (expected %X/%X)",
+				 errmsg_internal("incorrect commit LSN %X/%08X in commit message (expected %X/%08X)",
 								 LSN_FORMAT_ARGS(commit_data.commit_lsn),
 								 LSN_FORMAT_ARGS(remote_final_lsn))));
 
@@ -1108,7 +1300,7 @@ apply_handle_prepare(StringInfo s)
 	if (prepare_data.prepare_lsn != remote_final_lsn)
 		ereport(ERROR,
 				(errcode(ERRCODE_PROTOCOL_VIOLATION),
-				 errmsg_internal("incorrect prepare LSN %X/%X in prepare message (expected %X/%X)",
+				 errmsg_internal("incorrect prepare LSN %X/%08X in prepare message (expected %X/%08X)",
 								 LSN_FORMAT_ARGS(prepare_data.prepare_lsn),
 								 LSN_FORMAT_ARGS(remote_final_lsn))));
 
@@ -2726,17 +2918,31 @@ apply_handle_update_internal(ApplyExecutionData *edata,
 	}
 	else
 	{
+		ConflictType type;
 		TupleTableSlot *newslot = localslot;
 
+		/*
+		 * Detecting whether the tuple was recently deleted or never existed
+		 * is crucial to avoid misleading the user during confict handling.
+		 */
+		if (FindDeletedTupleInLocalRel(localrel, localindexoid, remoteslot,
+									   &conflicttuple.xmin,
+									   &conflicttuple.origin,
+									   &conflicttuple.ts) &&
+			conflicttuple.origin != replorigin_session_origin)
+			type = CT_UPDATE_DELETED;
+		else
+			type = CT_UPDATE_MISSING;
+
 		/* Store the new tuple for conflict reporting */
 		slot_store_data(newslot, relmapentry, newtup);
 
 		/*
-		 * The tuple to be updated could not be found.  Do nothing except for
-		 * emitting a log message.
+		 * The tuple to be updated could not be found or was deleted.  Do
+		 * nothing except for emitting a log message.
 		 */
-		ReportApplyConflict(estate, relinfo, LOG, CT_UPDATE_MISSING,
-							remoteslot, newslot, list_make1(&conflicttuple));
+		ReportApplyConflict(estate, relinfo, LOG, type, remoteslot, newslot,
+							list_make1(&conflicttuple));
 	}
 
 	/* Cleanup. */
@@ -2956,6 +3162,112 @@ FindReplTupleInLocalRel(ApplyExecutionData *edata, Relation localrel,
 	return found;
 }
 
+/*
+ * Determine whether the index can reliably locate the deleted tuple in the
+ * local relation.
+ *
+ * An index may exclude deleted tuples if it was re-indexed or re-created during
+ * change application. Therefore, an index is considered usable only if the
+ * conflict detection slot.xmin (conflict_detection_xmin) is greater than the
+ * index tuple's xmin. This ensures that any tuples deleted prior to the index
+ * creation or re-indexing are not relevant for conflict detection in the
+ * current apply worker.
+ *
+ * Note that indexes may also be excluded if they were modified by other DDL
+ * operations, such as ALTER INDEX. However, this is acceptable, as the
+ * likelihood of such DDL changes coinciding with the need to scan dead
+ * tuples for the update_deleted is low.
+ */
+static bool
+IsIndexUsableForFindingDeletedTuple(Oid localindexoid,
+									TransactionId conflict_detection_xmin)
+{
+	HeapTuple	index_tuple;
+	TransactionId index_xmin;
+
+	index_tuple = SearchSysCache1(INDEXRELID, ObjectIdGetDatum(localindexoid));
+
+	if (!HeapTupleIsValid(index_tuple)) /* should not happen */
+		elog(ERROR, "cache lookup failed for index %u", localindexoid);
+
+	/*
+	 * No need to check for a frozen transaction ID, as
+	 * TransactionIdPrecedes() manages it internally, treating it as falling
+	 * behind the conflict_detection_xmin.
+	 */
+	index_xmin = HeapTupleHeaderGetXmin(index_tuple->t_data);
+
+	ReleaseSysCache(index_tuple);
+
+	return TransactionIdPrecedes(index_xmin, conflict_detection_xmin);
+}
+
+/*
+ * Attempts to locate a deleted tuple in the local relation that matches the
+ * values of the tuple received from the publication side (in 'remoteslot').
+ * The search is performed using either the replica identity index, primary
+ * key, other available index, or a sequential scan if necessary.
+ *
+ * Returns true if the deleted tuple is found. If found, the transaction ID,
+ * origin, and commit timestamp of the deletion are stored in '*delete_xid',
+ * '*delete_origin', and '*delete_time' respectively.
+ */
+static bool
+FindDeletedTupleInLocalRel(Relation localrel, Oid localidxoid,
+						   TupleTableSlot *remoteslot,
+						   TransactionId *delete_xid, RepOriginId *delete_origin,
+						   TimestampTz *delete_time)
+{
+	TransactionId oldestxmin;
+	ReplicationSlot *slot;
+
+	/*
+	 * Return false if either dead tuples are not retained or commit timestamp
+	 * data is not available.
+	 */
+	if (!MySubscription->retaindeadtuples || !track_commit_timestamp)
+		return false;
+
+	/*
+	 * For conflict detection, we use the conflict slot's xmin value instead
+	 * of invoking GetOldestNonRemovableTransactionId(). The slot.xmin acts as
+	 * a threshold to identify tuples that were recently deleted. These tuples
+	 * are not visible to concurrent transactions, but we log an
+	 * update_deleted conflict if such a tuple matches the remote update being
+	 * applied.
+	 *
+	 * Although GetOldestNonRemovableTransactionId() can return a value older
+	 * than the slot's xmin, for our current purpose it is acceptable to treat
+	 * tuples deleted by transactions prior to slot.xmin as update_missing
+	 * conflicts.
+	 *
+	 * Ideally, we would use oldest_nonremovable_xid, which is directly
+	 * maintained by the leader apply worker. However, this value is not
+	 * available to table synchronization or parallel apply workers, making
+	 * slot.xmin a practical alternative in those contexts.
+	 */
+	slot = SearchNamedReplicationSlot(CONFLICT_DETECTION_SLOT, true);
+
+	Assert(slot);
+
+	SpinLockAcquire(&slot->mutex);
+	oldestxmin = slot->data.xmin;
+	SpinLockRelease(&slot->mutex);
+
+	Assert(TransactionIdIsValid(oldestxmin));
+
+	if (OidIsValid(localidxoid) &&
+		IsIndexUsableForFindingDeletedTuple(localidxoid, oldestxmin))
+		return RelationFindDeletedTupleInfoByIndex(localrel, localidxoid,
+												   remoteslot, oldestxmin,
+												   delete_xid, delete_origin,
+												   delete_time);
+	else
+		return RelationFindDeletedTupleInfoSeq(localrel, remoteslot,
+											   oldestxmin, delete_xid,
+											   delete_origin, delete_time);
+}
+
 /*
  * This handles insert, update, delete on a partitioned table.
  */
@@ -3074,18 +3386,35 @@ apply_handle_tuple_routing(ApplyExecutionData *edata,
 												remoteslot_part, &localslot);
 				if (!found)
 				{
+					ConflictType type;
 					TupleTableSlot *newslot = localslot;
 
+					/*
+					 * Detecting whether the tuple was recently deleted or
+					 * never existed is crucial to avoid misleading the user
+					 * during confict handling.
+					 */
+					if (FindDeletedTupleInLocalRel(partrel,
+												   part_entry->localindexoid,
+												   remoteslot_part,
+												   &conflicttuple.xmin,
+												   &conflicttuple.origin,
+												   &conflicttuple.ts) &&
+						conflicttuple.origin != replorigin_session_origin)
+						type = CT_UPDATE_DELETED;
+					else
+						type = CT_UPDATE_MISSING;
+
 					/* Store the new tuple for conflict reporting */
 					slot_store_data(newslot, part_entry, newtup);
 
 					/*
-					 * The tuple to be updated could not be found.  Do nothing
-					 * except for emitting a log message.
+					 * The tuple to be updated could not be found or was
+					 * deleted.  Do nothing except for emitting a log message.
 					 */
 					ReportApplyConflict(estate, partrelinfo, LOG,
-										CT_UPDATE_MISSING, remoteslot_part,
-										newslot, list_make1(&conflicttuple));
+										type, remoteslot_part, newslot,
+										list_make1(&conflicttuple));
 
 					return;
 				}
@@ -3577,6 +3906,7 @@ LogicalRepApplyLoop(XLogRecPtr last_received)
 	bool		ping_sent = false;
 	TimeLineID	tli;
 	ErrorContextCallback errcallback;
+	RetainDeadTuplesData rdt_data = {0};
 
 	/*
 	 * Init the ApplyMessageContext which we clean up after each replication
@@ -3655,6 +3985,8 @@ LogicalRepApplyLoop(XLogRecPtr last_received)
 					last_recv_timestamp = GetCurrentTimestamp();
 					ping_sent = false;
 
+					rdt_data.last_recv_time = last_recv_timestamp;
+
 					/* Ensure we are reading the data into our memory context. */
 					MemoryContextSwitchTo(ApplyMessageContext);
 
@@ -3681,6 +4013,8 @@ LogicalRepApplyLoop(XLogRecPtr last_received)
 						UpdateWorkerStats(last_received, send_time, false);
 
 						apply_dispatch(&s);
+
+						maybe_advance_nonremovable_xid(&rdt_data, false);
 					}
 					else if (c == 'k')
 					{
@@ -3696,8 +4030,31 @@ LogicalRepApplyLoop(XLogRecPtr last_received)
 							last_received = end_lsn;
 
 						send_feedback(last_received, reply_requested, false);
+
+						maybe_advance_nonremovable_xid(&rdt_data, false);
+
 						UpdateWorkerStats(last_received, timestamp, true);
 					}
+					else if (c == 's')	/* Primary status update */
+					{
+						rdt_data.remote_lsn = pq_getmsgint64(&s);
+						rdt_data.remote_oldestxid = FullTransactionIdFromU64((uint64) pq_getmsgint64(&s));
+						rdt_data.remote_nextxid = FullTransactionIdFromU64((uint64) pq_getmsgint64(&s));
+						rdt_data.reply_time = pq_getmsgint64(&s);
+
+						/*
+						 * This should never happen, see
+						 * ProcessStandbyPSRequestMessage. But if it happens
+						 * due to a bug, we don't want to proceed as it can
+						 * incorrectly advance oldest_nonremovable_xid.
+						 */
+						if (XLogRecPtrIsInvalid(rdt_data.remote_lsn))
+							elog(ERROR, "cannot get the latest WAL position from the publisher");
+
+						maybe_advance_nonremovable_xid(&rdt_data, true);
+
+						UpdateWorkerStats(last_received, rdt_data.reply_time, false);
+					}
 					/* other message types are purposefully ignored */
 
 					MemoryContextReset(ApplyMessageContext);
@@ -3710,6 +4067,11 @@ LogicalRepApplyLoop(XLogRecPtr last_received)
 		/* confirm all writes so far */
 		send_feedback(last_received, false, false);
 
+		/* Reset the timestamp if no message was received */
+		rdt_data.last_recv_time = 0;
+
+		maybe_advance_nonremovable_xid(&rdt_data, false);
+
 		if (!in_remote_transaction && !in_streamed_transaction)
 		{
 			/*
@@ -3744,6 +4106,14 @@ LogicalRepApplyLoop(XLogRecPtr last_received)
 		else
 			wait_time = NAPTIME_PER_CYCLE;
 
+		/*
+		 * Ensure to wake up when it's possible to advance the non-removable
+		 * transaction ID.
+		 */
+		if (rdt_data.phase == RDT_GET_CANDIDATE_XID &&
+			rdt_data.xid_advance_interval)
+			wait_time = Min(wait_time, rdt_data.xid_advance_interval);
+
 		rc = WaitLatchOrSocket(MyLatch,
 							   WL_SOCKET_READABLE | WL_LATCH_SET |
 							   WL_TIMEOUT | WL_EXIT_ON_PM_DEATH,
@@ -3807,6 +4177,8 @@ LogicalRepApplyLoop(XLogRecPtr last_received)
 
 			send_feedback(last_received, requestReply, requestReply);
 
+			maybe_advance_nonremovable_xid(&rdt_data, false);
+
 			/*
 			 * Force reporting to ensure long idle periods don't lead to
 			 * arbitrarily delayed stats. Stats can only be reported outside
@@ -3842,7 +4214,6 @@ send_feedback(XLogRecPtr recvpos, bool force, bool requestReply)
 
 	static XLogRecPtr last_recvpos = InvalidXLogRecPtr;
 	static XLogRecPtr last_writepos = InvalidXLogRecPtr;
-	static XLogRecPtr last_flushpos = InvalidXLogRecPtr;
 
 	XLogRecPtr	writepos;
 	XLogRecPtr	flushpos;
@@ -3903,7 +4274,7 @@ send_feedback(XLogRecPtr recvpos, bool force, bool requestReply)
 	pq_sendint64(reply_message, now);	/* sendTime */
 	pq_sendbyte(reply_message, requestReply);	/* replyRequested */
 
-	elog(DEBUG2, "sending feedback (force %d) to recv %X/%X, write %X/%X, flush %X/%X",
+	elog(DEBUG2, "sending feedback (force %d) to recv %X/%08X, write %X/%08X, flush %X/%08X",
 		 force,
 		 LSN_FORMAT_ARGS(recvpos),
 		 LSN_FORMAT_ARGS(writepos),
@@ -3920,6 +4291,368 @@ send_feedback(XLogRecPtr recvpos, bool force, bool requestReply)
 		last_flushpos = flushpos;
 }
 
+/*
+ * Attempt to advance the non-removable transaction ID.
+ *
+ * See comments atop worker.c for details.
+ */
+static void
+maybe_advance_nonremovable_xid(RetainDeadTuplesData *rdt_data,
+							   bool status_received)
+{
+	if (!can_advance_nonremovable_xid(rdt_data))
+		return;
+
+	process_rdt_phase_transition(rdt_data, status_received);
+}
+
+/*
+ * Preliminary check to determine if advancing the non-removable transaction ID
+ * is allowed.
+ */
+static bool
+can_advance_nonremovable_xid(RetainDeadTuplesData *rdt_data)
+{
+	/*
+	 * It is sufficient to manage non-removable transaction ID for a
+	 * subscription by the main apply worker to detect update_deleted reliably
+	 * even for table sync or parallel apply workers.
+	 */
+	if (!am_leader_apply_worker())
+		return false;
+
+	/* No need to advance if retaining dead tuples is not required */
+	if (!MySubscription->retaindeadtuples)
+		return false;
+
+	return true;
+}
+
+/*
+ * Process phase transitions during the non-removable transaction ID
+ * advancement. See comments atop worker.c for details of the transition.
+ */
+static void
+process_rdt_phase_transition(RetainDeadTuplesData *rdt_data,
+							 bool status_received)
+{
+	switch (rdt_data->phase)
+	{
+		case RDT_GET_CANDIDATE_XID:
+			get_candidate_xid(rdt_data);
+			break;
+		case RDT_REQUEST_PUBLISHER_STATUS:
+			request_publisher_status(rdt_data);
+			break;
+		case RDT_WAIT_FOR_PUBLISHER_STATUS:
+			wait_for_publisher_status(rdt_data, status_received);
+			break;
+		case RDT_WAIT_FOR_LOCAL_FLUSH:
+			wait_for_local_flush(rdt_data);
+			break;
+	}
+}
+
+/*
+ * Workhorse for the RDT_GET_CANDIDATE_XID phase.
+ */
+static void
+get_candidate_xid(RetainDeadTuplesData *rdt_data)
+{
+	TransactionId oldest_running_xid;
+	TimestampTz now;
+
+	/*
+	 * Use last_recv_time when applying changes in the loop to avoid
+	 * unnecessary system time retrieval. If last_recv_time is not available,
+	 * obtain the current timestamp.
+	 */
+	now = rdt_data->last_recv_time ? rdt_data->last_recv_time : GetCurrentTimestamp();
+
+	/*
+	 * Compute the candidate_xid and request the publisher status at most once
+	 * per xid_advance_interval. Refer to adjust_xid_advance_interval() for
+	 * details on how this value is dynamically adjusted. This is to avoid
+	 * using CPU and network resources without making much progress.
+	 */
+	if (!TimestampDifferenceExceeds(rdt_data->candidate_xid_time, now,
+									rdt_data->xid_advance_interval))
+		return;
+
+	/*
+	 * Immediately update the timer, even if the function returns later
+	 * without setting candidate_xid due to inactivity on the subscriber. This
+	 * avoids frequent calls to GetOldestActiveTransactionId.
+	 */
+	rdt_data->candidate_xid_time = now;
+
+	/*
+	 * Consider transactions in the current database, as only dead tuples from
+	 * this database are required for conflict detection.
+	 */
+	oldest_running_xid = GetOldestActiveTransactionId(false, false);
+
+	/*
+	 * Oldest active transaction ID (oldest_running_xid) can't be behind any
+	 * of its previously computed value.
+	 */
+	Assert(TransactionIdPrecedesOrEquals(MyLogicalRepWorker->oldest_nonremovable_xid,
+										 oldest_running_xid));
+
+	/* Return if the oldest_nonremovable_xid cannot be advanced */
+	if (TransactionIdEquals(MyLogicalRepWorker->oldest_nonremovable_xid,
+							oldest_running_xid))
+	{
+		adjust_xid_advance_interval(rdt_data, false);
+		return;
+	}
+
+	adjust_xid_advance_interval(rdt_data, true);
+
+	rdt_data->candidate_xid = oldest_running_xid;
+	rdt_data->phase = RDT_REQUEST_PUBLISHER_STATUS;
+
+	/* process the next phase */
+	process_rdt_phase_transition(rdt_data, false);
+}
+
+/*
+ * Workhorse for the RDT_REQUEST_PUBLISHER_STATUS phase.
+ */
+static void
+request_publisher_status(RetainDeadTuplesData *rdt_data)
+{
+	static StringInfo request_message = NULL;
+
+	if (!request_message)
+	{
+		MemoryContext oldctx = MemoryContextSwitchTo(ApplyContext);
+
+		request_message = makeStringInfo();
+		MemoryContextSwitchTo(oldctx);
+	}
+	else
+		resetStringInfo(request_message);
+
+	/*
+	 * Send the current time to update the remote walsender's latest reply
+	 * message received time.
+	 */
+	pq_sendbyte(request_message, 'p');
+	pq_sendint64(request_message, GetCurrentTimestamp());
+
+	elog(DEBUG2, "sending publisher status request message");
+
+	/* Send a request for the publisher status */
+	walrcv_send(LogRepWorkerWalRcvConn,
+				request_message->data, request_message->len);
+
+	rdt_data->phase = RDT_WAIT_FOR_PUBLISHER_STATUS;
+
+	/*
+	 * Skip calling maybe_advance_nonremovable_xid() since further transition
+	 * is possible only once we receive the publisher status message.
+	 */
+}
+
+/*
+ * Workhorse for the RDT_WAIT_FOR_PUBLISHER_STATUS phase.
+ */
+static void
+wait_for_publisher_status(RetainDeadTuplesData *rdt_data,
+						  bool status_received)
+{
+	/*
+	 * Return if we have requested but not yet received the publisher status.
+	 */
+	if (!status_received)
+		return;
+
+	if (!FullTransactionIdIsValid(rdt_data->remote_wait_for))
+		rdt_data->remote_wait_for = rdt_data->remote_nextxid;
+
+	/*
+	 * Check if all remote concurrent transactions that were active at the
+	 * first status request have now completed. If completed, proceed to the
+	 * next phase; otherwise, continue checking the publisher status until
+	 * these transactions finish.
+	 *
+	 * It's possible that transactions in the commit phase during the last
+	 * cycle have now finished committing, but remote_oldestxid remains older
+	 * than remote_wait_for. This can happen if some old transaction came in
+	 * the commit phase when we requested status in this cycle. We do not
+	 * handle this case explicitly as it's rare and the benefit doesn't
+	 * justify the required complexity. Tracking would require either caching
+	 * all xids at the publisher or sending them to subscribers. The condition
+	 * will resolve naturally once the remaining transactions are finished.
+	 *
+	 * Directly advancing the non-removable transaction ID is possible if
+	 * there are no activities on the publisher since the last advancement
+	 * cycle. However, it requires maintaining two fields, last_remote_nextxid
+	 * and last_remote_lsn, within the structure for comparison with the
+	 * current cycle's values. Considering the minimal cost of continuing in
+	 * RDT_WAIT_FOR_LOCAL_FLUSH without awaiting changes, we opted not to
+	 * advance the transaction ID here.
+	 */
+	if (FullTransactionIdPrecedesOrEquals(rdt_data->remote_wait_for,
+										  rdt_data->remote_oldestxid))
+		rdt_data->phase = RDT_WAIT_FOR_LOCAL_FLUSH;
+	else
+		rdt_data->phase = RDT_REQUEST_PUBLISHER_STATUS;
+
+	/* process the next phase */
+	process_rdt_phase_transition(rdt_data, false);
+}
+
+/*
+ * Workhorse for the RDT_WAIT_FOR_LOCAL_FLUSH phase.
+ */
+static void
+wait_for_local_flush(RetainDeadTuplesData *rdt_data)
+{
+	Assert(!XLogRecPtrIsInvalid(rdt_data->remote_lsn) &&
+		   TransactionIdIsValid(rdt_data->candidate_xid));
+
+	/*
+	 * We expect the publisher and subscriber clocks to be in sync using time
+	 * sync service like NTP. Otherwise, we will advance this worker's
+	 * oldest_nonremovable_xid prematurely, leading to the removal of rows
+	 * required to detect update_deleted reliably. This check primarily
+	 * addresses scenarios where the publisher's clock falls behind; if the
+	 * publisher's clock is ahead, subsequent transactions will naturally bear
+	 * later commit timestamps, conforming to the design outlined atop
+	 * worker.c.
+	 *
+	 * XXX Consider waiting for the publisher's clock to catch up with the
+	 * subscriber's before proceeding to the next phase.
+	 */
+	if (TimestampDifferenceExceeds(rdt_data->reply_time,
+								   rdt_data->candidate_xid_time, 0))
+		ereport(ERROR,
+				errmsg_internal("oldest_nonremovable_xid transaction ID could be advanced prematurely"),
+				errdetail_internal("The clock on the publisher is behind that of the subscriber."));
+
+	/*
+	 * Do not attempt to advance the non-removable transaction ID when table
+	 * sync is in progress. During this time, changes from a single
+	 * transaction may be applied by multiple table sync workers corresponding
+	 * to the target tables. So, it's necessary for all table sync workers to
+	 * apply and flush the corresponding changes before advancing the
+	 * transaction ID, otherwise, dead tuples that are still needed for
+	 * conflict detection in table sync workers could be removed prematurely.
+	 * However, confirming the apply and flush progress across all table sync
+	 * workers is complex and not worth the effort, so we simply return if not
+	 * all tables are in the READY state.
+	 *
+	 * It is safe to add new tables with initial states to the subscription
+	 * after this check because any changes applied to these tables should
+	 * have a WAL position greater than the rdt_data->remote_lsn.
+	 */
+	if (!AllTablesyncsReady())
+		return;
+
+	/*
+	 * Update and check the remote flush position if we are applying changes
+	 * in a loop. This is done at most once per WalWriterDelay to avoid
+	 * performing costly operations in get_flush_position() too frequently
+	 * during change application.
+	 */
+	if (last_flushpos < rdt_data->remote_lsn && rdt_data->last_recv_time &&
+		TimestampDifferenceExceeds(rdt_data->flushpos_update_time,
+								   rdt_data->last_recv_time, WalWriterDelay))
+	{
+		XLogRecPtr	writepos;
+		XLogRecPtr	flushpos;
+		bool		have_pending_txes;
+
+		/* Fetch the latest remote flush position */
+		get_flush_position(&writepos, &flushpos, &have_pending_txes);
+
+		if (flushpos > last_flushpos)
+			last_flushpos = flushpos;
+
+		rdt_data->flushpos_update_time = rdt_data->last_recv_time;
+	}
+
+	/* Return to wait for the changes to be applied */
+	if (last_flushpos < rdt_data->remote_lsn)
+		return;
+
+	/*
+	 * Reaching here means the remote WAL position has been received, and all
+	 * transactions up to that position on the publisher have been applied and
+	 * flushed locally. So, we can advance the non-removable transaction ID.
+	 */
+	SpinLockAcquire(&MyLogicalRepWorker->relmutex);
+	MyLogicalRepWorker->oldest_nonremovable_xid = rdt_data->candidate_xid;
+	SpinLockRelease(&MyLogicalRepWorker->relmutex);
+
+	elog(DEBUG2, "confirmed flush up to remote lsn %X/%X: new oldest_nonremovable_xid %u",
+		 LSN_FORMAT_ARGS(rdt_data->remote_lsn),
+		 rdt_data->candidate_xid);
+
+	/* Notify launcher to update the xmin of the conflict slot */
+	ApplyLauncherWakeup();
+
+	/*
+	 * Reset all data fields except those used to determine the timing for the
+	 * next round of transaction ID advancement. We can even use
+	 * flushpos_update_time in the next round to decide whether to get the
+	 * latest flush position.
+	 */
+	rdt_data->phase = RDT_GET_CANDIDATE_XID;
+	rdt_data->remote_lsn = InvalidXLogRecPtr;
+	rdt_data->remote_oldestxid = InvalidFullTransactionId;
+	rdt_data->remote_nextxid = InvalidFullTransactionId;
+	rdt_data->reply_time = 0;
+	rdt_data->remote_wait_for = InvalidFullTransactionId;
+	rdt_data->candidate_xid = InvalidTransactionId;
+
+	/* process the next phase */
+	process_rdt_phase_transition(rdt_data, false);
+}
+
+/*
+ * Adjust the interval for advancing non-removable transaction IDs.
+ *
+ * We double the interval to try advancing the non-removable transaction IDs
+ * if there is no activity on the node. The maximum value of the interval is
+ * capped by wal_receiver_status_interval if it is not zero, otherwise to a
+ * 3 minutes which should be sufficient to avoid using CPU or network
+ * resources without much benefit.
+ *
+ * The interval is reset to a minimum value of 100ms once there is some
+ * activity on the node.
+ *
+ * XXX The use of wal_receiver_status_interval is a bit arbitrary so we can
+ * consider the other interval or a separate GUC if the need arises.
+ */
+static void
+adjust_xid_advance_interval(RetainDeadTuplesData *rdt_data, bool new_xid_found)
+{
+	if (!new_xid_found && rdt_data->xid_advance_interval)
+	{
+		int			max_interval = wal_receiver_status_interval
+			? wal_receiver_status_interval * 1000
+			: MAX_XID_ADVANCE_INTERVAL;
+
+		/*
+		 * No new transaction ID has been assigned since the last check, so
+		 * double the interval, but not beyond the maximum allowable value.
+		 */
+		rdt_data->xid_advance_interval = Min(rdt_data->xid_advance_interval * 2,
+											 max_interval);
+	}
+	else
+	{
+		/*
+		 * A new transaction ID was found or the interval is not yet
+		 * initialized, so set the interval to the minimum value.
+		 */
+		rdt_data->xid_advance_interval = MIN_XID_ADVANCE_INTERVAL;
+	}
+}
+
 /*
  * Exit routine for apply workers due to subscription parameter changes.
  */
@@ -4708,6 +5441,30 @@ InitializeLogRepWorker(void)
 		apply_worker_exit();
 	}
 
+	/*
+	 * Restart the worker if retain_dead_tuples was enabled during startup.
+	 *
+	 * At this point, the replication slot used for conflict detection might
+	 * not exist yet, or could be dropped soon if the launcher perceives
+	 * retain_dead_tuples as disabled. To avoid unnecessary tracking of
+	 * oldest_nonremovable_xid when the slot is absent or at risk of being
+	 * dropped, a restart is initiated.
+	 *
+	 * The oldest_nonremovable_xid should be initialized only when the
+	 * retain_dead_tuples is enabled before launching the worker. See
+	 * logicalrep_worker_launch.
+	 */
+	if (am_leader_apply_worker() &&
+		MySubscription->retaindeadtuples &&
+		!TransactionIdIsValid(MyLogicalRepWorker->oldest_nonremovable_xid))
+	{
+		ereport(LOG,
+				errmsg("logical replication worker for subscription \"%s\" will restart because the option %s was enabled during startup",
+					   MySubscription->name, "retain_dead_tuples"));
+
+		apply_worker_exit();
+	}
+
 	/* Setup synchronous commit according to the user's wishes */
 	SetConfigOption("synchronous_commit", MySubscription->synccommit,
 					PGC_BACKEND, PGC_S_OVERRIDE);
@@ -4864,6 +5621,14 @@ DisableSubscriptionAndExit(void)
 			errmsg("subscription \"%s\" has been disabled because of an error",
 				   MySubscription->name));
 
+	/*
+	 * Skip the track_commit_timestamp check when disabling the worker due to
+	 * an error, as verifying commit timestamps is unnecessary in this
+	 * context.
+	 */
+	if (MySubscription->retaindeadtuples)
+		CheckSubDeadTupleRetention(false, true, WARNING);
+
 	proc_exit(0);
 }
 
@@ -4909,7 +5674,7 @@ maybe_start_skipping_changes(XLogRecPtr finish_lsn)
 	skip_xact_finish_lsn = finish_lsn;
 
 	ereport(LOG,
-			errmsg("logical replication starts skipping transaction at LSN %X/%X",
+			errmsg("logical replication starts skipping transaction at LSN %X/%08X",
 				   LSN_FORMAT_ARGS(skip_xact_finish_lsn)));
 }
 
@@ -4923,8 +5688,8 @@ stop_skipping_changes(void)
 		return;
 
 	ereport(LOG,
-			(errmsg("logical replication completed skipping transaction at LSN %X/%X",
-					LSN_FORMAT_ARGS(skip_xact_finish_lsn))));
+			errmsg("logical replication completed skipping transaction at LSN %X/%08X",
+				   LSN_FORMAT_ARGS(skip_xact_finish_lsn)));
 
 	/* Stop skipping changes */
 	skip_xact_finish_lsn = InvalidXLogRecPtr;
@@ -5012,7 +5777,7 @@ clear_subscription_skip_lsn(XLogRecPtr finish_lsn)
 		if (myskiplsn != finish_lsn)
 			ereport(WARNING,
 					errmsg("skip-LSN of subscription \"%s\" cleared", MySubscription->name),
-					errdetail("Remote transaction's finish WAL location (LSN) %X/%X did not match skip-LSN %X/%X.",
+					errdetail("Remote transaction's finish WAL location (LSN) %X/%08X did not match skip-LSN %X/%08X.",
 							  LSN_FORMAT_ARGS(finish_lsn),
 							  LSN_FORMAT_ARGS(myskiplsn)));
 	}
@@ -5049,7 +5814,7 @@ apply_error_callback(void *arg)
 					   logicalrep_message_type(errarg->command),
 					   errarg->remote_xid);
 		else
-			errcontext("processing remote data for replication origin \"%s\" during message type \"%s\" in transaction %u, finished at %X/%X",
+			errcontext("processing remote data for replication origin \"%s\" during message type \"%s\" in transaction %u, finished at %X/%08X",
 					   errarg->origin_name,
 					   logicalrep_message_type(errarg->command),
 					   errarg->remote_xid,
@@ -5067,7 +5832,7 @@ apply_error_callback(void *arg)
 						   errarg->rel->remoterel.relname,
 						   errarg->remote_xid);
 			else
-				errcontext("processing remote data for replication origin \"%s\" during message type \"%s\" for replication target relation \"%s.%s\" in transaction %u, finished at %X/%X",
+				errcontext("processing remote data for replication origin \"%s\" during message type \"%s\" for replication target relation \"%s.%s\" in transaction %u, finished at %X/%08X",
 						   errarg->origin_name,
 						   logicalrep_message_type(errarg->command),
 						   errarg->rel->remoterel.nspname,
@@ -5086,7 +5851,7 @@ apply_error_callback(void *arg)
 						   errarg->rel->remoterel.attnames[errarg->remote_attnum],
 						   errarg->remote_xid);
 			else
-				errcontext("processing remote data for replication origin \"%s\" during message type \"%s\" for replication target relation \"%s.%s\" column \"%s\" in transaction %u, finished at %X/%X",
+				errcontext("processing remote data for replication origin \"%s\" during message type \"%s\" for replication target relation \"%s.%s\" column \"%s\" in transaction %u, finished at %X/%08X",
 						   errarg->origin_name,
 						   logicalrep_message_type(errarg->command),
 						   errarg->rel->remoterel.nspname,
diff --git a/src/backend/replication/pgoutput/pgoutput.c b/src/backend/replication/pgoutput/pgoutput.c
index 082b4d9d32798..80540c017bd3a 100644
--- a/src/backend/replication/pgoutput/pgoutput.c
+++ b/src/backend/replication/pgoutput/pgoutput.c
@@ -297,10 +297,12 @@ parse_output_parameters(List *options, PGOutputData *data)
 	bool		two_phase_option_given = false;
 	bool		origin_option_given = false;
 
+	/* Initialize optional parameters to defaults */
 	data->binary = false;
 	data->streaming = LOGICALREP_STREAM_OFF;
 	data->messages = false;
 	data->two_phase = false;
+	data->publish_no_origin = false;
 
 	foreach(lc, options)
 	{
@@ -1372,8 +1374,8 @@ pgoutput_row_filter(Relation relation, TupleTableSlot *old_slot,
 		 * VARTAG_INDIRECT. See ReorderBufferToastReplace.
 		 */
 		if (att->attlen == -1 &&
-			VARATT_IS_EXTERNAL_ONDISK(new_slot->tts_values[i]) &&
-			!VARATT_IS_EXTERNAL_ONDISK(old_slot->tts_values[i]))
+			VARATT_IS_EXTERNAL_ONDISK(DatumGetPointer(new_slot->tts_values[i])) &&
+			!VARATT_IS_EXTERNAL_ONDISK(DatumGetPointer(old_slot->tts_values[i])))
 		{
 			if (!tmp_new_slot)
 			{
diff --git a/src/backend/replication/repl_gram.y b/src/backend/replication/repl_gram.y
index 7440aae5a1a7e..8a649199ec69c 100644
--- a/src/backend/replication/repl_gram.y
+++ b/src/backend/replication/repl_gram.y
@@ -279,7 +279,7 @@ alter_replication_slot:
 			;
 
 /*
- * START_REPLICATION [SLOT slot] [PHYSICAL] %X/%X [TIMELINE %u]
+ * START_REPLICATION [SLOT slot] [PHYSICAL] %X/%08X [TIMELINE %u]
  */
 start_replication:
 			K_START_REPLICATION opt_slot opt_physical RECPTR opt_timeline
@@ -295,7 +295,7 @@ start_replication:
 				}
 			;
 
-/* START_REPLICATION SLOT slot LOGICAL %X/%X options */
+/* START_REPLICATION SLOT slot LOGICAL %X/%08X options */
 start_logical_replication:
 			K_START_REPLICATION K_SLOT IDENT K_LOGICAL RECPTR plugin_options
 				{
diff --git a/src/backend/replication/repl_scanner.l b/src/backend/replication/repl_scanner.l
index 014ea8d25c6b7..b6930e2865953 100644
--- a/src/backend/replication/repl_scanner.l
+++ b/src/backend/replication/repl_scanner.l
@@ -155,7 +155,7 @@ UPLOAD_MANIFEST		{ return K_UPLOAD_MANIFEST; }
 {hexdigit}+\/{hexdigit}+		{
 					uint32	hi,
 							lo;
-					if (sscanf(yytext, "%X/%X", &hi, &lo) != 2)
+					if (sscanf(yytext, "%X/%08X", &hi, &lo) != 2)
 						replication_yyerror(NULL, yyscanner, "invalid streaming start location");
 					yylval->recptr = ((uint64) hi) << 32 | lo;
 					return RECPTR;
diff --git a/src/backend/replication/slot.c b/src/backend/replication/slot.c
index f9fec50ae883f..8605776ad8631 100644
--- a/src/backend/replication/slot.c
+++ b/src/backend/replication/slot.c
@@ -47,6 +47,7 @@
 #include "miscadmin.h"
 #include "pgstat.h"
 #include "postmaster/interrupt.h"
+#include "replication/logicallauncher.h"
 #include "replication/slotsync.h"
 #include "replication/slot.h"
 #include "replication/walsender_private.h"
@@ -154,7 +155,7 @@ int			max_replication_slots = 10; /* the maximum number of replication
  * Invalidate replication slots that have remained idle longer than this
  * duration; '0' disables it.
  */
-int			idle_replication_slot_timeout_mins = 0;
+int			idle_replication_slot_timeout_secs = 0;
 
 /*
  * This GUC lists streaming replication standby server slot names that
@@ -172,6 +173,7 @@ static SyncStandbySlotsConfigData *synchronized_standby_slots_config;
 static XLogRecPtr ss_oldest_flush_lsn = InvalidXLogRecPtr;
 
 static void ReplicationSlotShmemExit(int code, Datum arg);
+static bool IsSlotForConflictCheck(const char *name);
 static void ReplicationSlotDropPtr(ReplicationSlot *slot);
 
 /* internal persistency functions */
@@ -258,13 +260,17 @@ ReplicationSlotShmemExit(int code, Datum arg)
 /*
  * Check whether the passed slot name is valid and report errors at elevel.
  *
+ * An error will be reported for a reserved replication slot name if
+ * allow_reserved_name is set to false.
+ *
  * Slot names may consist out of [a-z0-9_]{1,NAMEDATALEN-1} which should allow
  * the name to be used as a directory name on every supported OS.
  *
  * Returns whether the directory name is valid or not if elevel < ERROR.
  */
 bool
-ReplicationSlotValidateName(const char *name, int elevel)
+ReplicationSlotValidateName(const char *name, bool allow_reserved_name,
+							int elevel)
 {
 	const char *cp;
 
@@ -300,9 +306,31 @@ ReplicationSlotValidateName(const char *name, int elevel)
 			return false;
 		}
 	}
+
+	if (!allow_reserved_name && IsSlotForConflictCheck(name))
+	{
+		ereport(elevel,
+				errcode(ERRCODE_RESERVED_NAME),
+				errmsg("replication slot name \"%s\" is reserved",
+					   name),
+				errdetail("The name \"%s\" is reserved for the conflict detection slot.",
+						  CONFLICT_DETECTION_SLOT));
+
+		return false;
+	}
+
 	return true;
 }
 
+/*
+ * Return true if the replication slot name is "pg_conflict_detection".
+ */
+static bool
+IsSlotForConflictCheck(const char *name)
+{
+	return (strcmp(name, CONFLICT_DETECTION_SLOT) == 0);
+}
+
 /*
  * Create a new replication slot and mark it as used by this backend.
  *
@@ -330,7 +358,12 @@ ReplicationSlotCreate(const char *name, bool db_specific,
 
 	Assert(MyReplicationSlot == NULL);
 
-	ReplicationSlotValidateName(name, ERROR);
+	/*
+	 * The logical launcher or pg_upgrade may create or migrate an internal
+	 * slot, so using a reserved name is allowed in these cases.
+	 */
+	ReplicationSlotValidateName(name, IsBinaryUpgrade || IsLogicalLauncher(),
+								ERROR);
 
 	if (failover)
 	{
@@ -581,6 +614,17 @@ ReplicationSlotAcquire(const char *name, bool nowait, bool error_if_invalid)
 						name)));
 	}
 
+	/*
+	 * Do not allow users to acquire the reserved slot. This scenario may
+	 * occur if the launcher that owns the slot has terminated unexpectedly
+	 * due to an error, and a backend process attempts to reuse the slot.
+	 */
+	if (!IsLogicalLauncher() && IsSlotForConflictCheck(name))
+		ereport(ERROR,
+				errcode(ERRCODE_UNDEFINED_OBJECT),
+				errmsg("cannot acquire replication slot \"%s\"", name),
+				errdetail("The slot is reserved for conflict detection and can only be acquired by logical replication launcher."));
+
 	/*
 	 * This is the slot we want; check if it's active under some other
 	 * process.  In single user mode, we don't need this check.
@@ -1591,8 +1635,8 @@ ReportSlotInvalidation(ReplicationSlotInvalidationCause cause,
 				uint64		ex = oldestLSN - restart_lsn;
 
 				appendStringInfo(&err_detail,
-								 ngettext("The slot's restart_lsn %X/%X exceeds the limit by %" PRIu64 " byte.",
-										  "The slot's restart_lsn %X/%X exceeds the limit by %" PRIu64 " bytes.",
+								 ngettext("The slot's restart_lsn %X/%08X exceeds the limit by %" PRIu64 " byte.",
+										  "The slot's restart_lsn %X/%08X exceeds the limit by %" PRIu64 " bytes.",
 										  ex),
 								 LSN_FORMAT_ARGS(restart_lsn),
 								 ex);
@@ -1612,13 +1656,10 @@ ReportSlotInvalidation(ReplicationSlotInvalidationCause cause,
 
 		case RS_INVAL_IDLE_TIMEOUT:
 			{
-				int			minutes = slot_idle_seconds / SECS_PER_MINUTE;
-				int			secs = slot_idle_seconds % SECS_PER_MINUTE;
-
 				/* translator: %s is a GUC variable name */
-				appendStringInfo(&err_detail, _("The slot's idle time of %dmin %02ds exceeds the configured \"%s\" duration of %dmin."),
-								 minutes, secs, "idle_replication_slot_timeout",
-								 idle_replication_slot_timeout_mins);
+				appendStringInfo(&err_detail, _("The slot's idle time of %lds exceeds the configured \"%s\" duration of %ds."),
+								 slot_idle_seconds, "idle_replication_slot_timeout",
+								 idle_replication_slot_timeout_secs);
 				/* translator: %s is a GUC variable name */
 				appendStringInfo(&err_hint, _("You might need to increase \"%s\"."),
 								 "idle_replication_slot_timeout");
@@ -1656,7 +1697,7 @@ ReportSlotInvalidation(ReplicationSlotInvalidationCause cause,
 static inline bool
 CanInvalidateIdleSlot(ReplicationSlot *s)
 {
-	return (idle_replication_slot_timeout_mins != 0 &&
+	return (idle_replication_slot_timeout_secs != 0 &&
 			!XLogRecPtrIsInvalid(s->data.restart_lsn) &&
 			s->inactive_since > 0 &&
 			!(RecoveryInProgress() && s->data.synced));
@@ -1717,9 +1758,9 @@ DetermineSlotInvalidationCause(uint32 possible_causes, ReplicationSlot *s,
 		if (CanInvalidateIdleSlot(s))
 		{
 			/*
-			 * We simulate the invalidation due to idle_timeout as the minimum
-			 * time idle time is one minute which makes tests take a long
-			 * time.
+			 * Simulate the invalidation due to idle_timeout to test the
+			 * timeout behavior promptly, without waiting for it to trigger
+			 * naturally.
 			 */
 #ifdef USE_INJECTION_POINTS
 			if (IS_INJECTION_POINT_ATTACHED("slot-timeout-inval"))
@@ -1734,7 +1775,7 @@ DetermineSlotInvalidationCause(uint32 possible_causes, ReplicationSlot *s,
 			 * idle_replication_slot_timeout GUC.
 			 */
 			if (TimestampDifferenceExceedsSeconds(s->inactive_since, now,
-												  idle_replication_slot_timeout_mins * SECS_PER_MINUTE))
+												  idle_replication_slot_timeout_secs))
 			{
 				*inactive_since = s->inactive_since;
 				return RS_INVAL_IDLE_TIMEOUT;
@@ -1890,15 +1931,6 @@ InvalidatePossiblyObsoleteSlot(uint32 possible_causes,
 
 		SpinLockRelease(&s->mutex);
 
-		/*
-		 * The logical replication slots shouldn't be invalidated as GUC
-		 * max_slot_wal_keep_size is set to -1 and
-		 * idle_replication_slot_timeout is set to 0 during the binary
-		 * upgrade. See check_old_cluster_for_valid_slots() where we ensure
-		 * that no invalidated before the upgrade.
-		 */
-		Assert(!(*invalidated && SlotIsLogical(s) && IsBinaryUpgrade));
-
 		/*
 		 * Calculate the idle time duration of the slot if slot is marked
 		 * invalidated with RS_INVAL_IDLE_TIMEOUT.
@@ -2045,6 +2077,10 @@ InvalidateObsoleteReplicationSlots(uint32 possible_causes,
 		if (!s->in_use)
 			continue;
 
+		/* Prevent invalidation of logical slots during binary upgrade */
+		if (SlotIsLogical(s) && IsBinaryUpgrade)
+			continue;
+
 		if (InvalidatePossiblyObsoleteSlot(possible_causes, s, oldestLSN, dboid,
 										   snapshotConflictHorizon,
 										   &invalidated))
@@ -3057,22 +3093,3 @@ WaitForStandbyConfirmation(XLogRecPtr wait_for_lsn)
 
 	ConditionVariableCancelSleep();
 }
-
-/*
- * GUC check_hook for idle_replication_slot_timeout
- *
- * The value of idle_replication_slot_timeout must be set to 0 during
- * a binary upgrade. See start_postmaster() in pg_upgrade for more details.
- */
-bool
-check_idle_replication_slot_timeout(int *newval, void **extra, GucSource source)
-{
-	if (IsBinaryUpgrade && *newval != 0)
-	{
-		GUC_check_errdetail("\"%s\" must be set to 0 during binary upgrade mode.",
-							"idle_replication_slot_timeout");
-		return false;
-	}
-
-	return true;
-}
diff --git a/src/backend/replication/slotfuncs.c b/src/backend/replication/slotfuncs.c
index 36cc2ed4e440f..69f4c6157c518 100644
--- a/src/backend/replication/slotfuncs.c
+++ b/src/backend/replication/slotfuncs.c
@@ -566,7 +566,7 @@ pg_replication_slot_advance(PG_FUNCTION_ARGS)
 	if (moveto < minlsn)
 		ereport(ERROR,
 				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-				 errmsg("cannot advance replication slot to %X/%X, minimum is %X/%X",
+				 errmsg("cannot advance replication slot to %X/%08X, minimum is %X/%08X",
 						LSN_FORMAT_ARGS(moveto), LSN_FORMAT_ARGS(minlsn))));
 
 	/* Do the actual slot update, depending on the slot type */
diff --git a/src/backend/replication/syncrep.c b/src/backend/replication/syncrep.c
index cc35984ad0085..32cf3a48b897d 100644
--- a/src/backend/replication/syncrep.c
+++ b/src/backend/replication/syncrep.c
@@ -258,7 +258,7 @@ SyncRepWaitForLSN(XLogRecPtr lsn, bool commit)
 	{
 		char		buffer[32];
 
-		sprintf(buffer, "waiting for %X/%X", LSN_FORMAT_ARGS(lsn));
+		sprintf(buffer, "waiting for %X/%08X", LSN_FORMAT_ARGS(lsn));
 		set_ps_display_suffix(buffer);
 	}
 
@@ -566,7 +566,7 @@ SyncRepReleaseWaiters(void)
 
 	LWLockRelease(SyncRepLock);
 
-	elog(DEBUG3, "released %d procs up to write %X/%X, %d procs up to flush %X/%X, %d procs up to apply %X/%X",
+	elog(DEBUG3, "released %d procs up to write %X/%08X, %d procs up to flush %X/%08X, %d procs up to apply %X/%08X",
 		 numwrite, LSN_FORMAT_ARGS(writePtr),
 		 numflush, LSN_FORMAT_ARGS(flushPtr),
 		 numapply, LSN_FORMAT_ARGS(applyPtr));
diff --git a/src/backend/replication/syncrep_scanner.l b/src/backend/replication/syncrep_scanner.l
index 7dec1f869c745..02004d621e73d 100644
--- a/src/backend/replication/syncrep_scanner.l
+++ b/src/backend/replication/syncrep_scanner.l
@@ -157,17 +157,16 @@ syncrep_yyerror(SyncRepConfigData **syncrep_parse_result_p, char **syncrep_parse
 {
 	struct yyguts_t *yyg = (struct yyguts_t *) yyscanner;	/* needed for yytext
 															 * macro */
-	char *syncrep_parse_error_msg = *syncrep_parse_error_msg_p;
 
 	/* report only the first error in a parse operation */
-	if (syncrep_parse_error_msg)
+	if (*syncrep_parse_error_msg_p)
 		return;
 	if (yytext[0])
-		syncrep_parse_error_msg = psprintf("%s at or near \"%s\"",
-										   message, yytext);
+		*syncrep_parse_error_msg_p = psprintf("%s at or near \"%s\"",
+											  message, yytext);
 	else
-		syncrep_parse_error_msg = psprintf("%s at end of input",
-										   message);
+		*syncrep_parse_error_msg_p = psprintf("%s at end of input",
+											  message);
 }
 
 void
diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c
index 8c4d0fd9aed2b..b62811017116f 100644
--- a/src/backend/replication/walreceiver.c
+++ b/src/backend/replication/walreceiver.c
@@ -386,12 +386,12 @@ WalReceiverMain(const void *startup_data, size_t startup_data_len)
 		{
 			if (first_stream)
 				ereport(LOG,
-						(errmsg("started streaming WAL from primary at %X/%X on timeline %u",
-								LSN_FORMAT_ARGS(startpoint), startpointTLI)));
+						errmsg("started streaming WAL from primary at %X/%08X on timeline %u",
+							   LSN_FORMAT_ARGS(startpoint), startpointTLI));
 			else
 				ereport(LOG,
-						(errmsg("restarted WAL streaming at %X/%X on timeline %u",
-								LSN_FORMAT_ARGS(startpoint), startpointTLI)));
+						errmsg("restarted WAL streaming at %X/%08X on timeline %u",
+							   LSN_FORMAT_ARGS(startpoint), startpointTLI));
 			first_stream = false;
 
 			/* Initialize LogstreamResult and buffers for processing messages */
@@ -470,7 +470,7 @@ WalReceiverMain(const void *startup_data, size_t startup_data_len)
 						{
 							ereport(LOG,
 									(errmsg("replication terminated by primary server"),
-									 errdetail("End of WAL reached on timeline %u at %X/%X.",
+									 errdetail("End of WAL reached on timeline %u at %X/%08X.",
 											   startpointTLI,
 											   LSN_FORMAT_ARGS(LogstreamResult.Write))));
 							endofwal = true;
@@ -711,7 +711,7 @@ WalRcvWaitForStartPosition(XLogRecPtr *startpoint, TimeLineID *startpointTLI)
 	{
 		char		activitymsg[50];
 
-		snprintf(activitymsg, sizeof(activitymsg), "restarting at %X/%X",
+		snprintf(activitymsg, sizeof(activitymsg), "restarting at %X/%08X",
 				 LSN_FORMAT_ARGS(*startpoint));
 		set_ps_display(activitymsg);
 	}
@@ -1014,7 +1014,7 @@ XLogWalRcvFlush(bool dying, TimeLineID tli)
 		{
 			char		activitymsg[50];
 
-			snprintf(activitymsg, sizeof(activitymsg), "streaming %X/%X",
+			snprintf(activitymsg, sizeof(activitymsg), "streaming %X/%08X",
 					 LSN_FORMAT_ARGS(LogstreamResult.Write));
 			set_ps_display(activitymsg);
 		}
@@ -1138,7 +1138,7 @@ XLogWalRcvSendReply(bool force, bool requestReply)
 	pq_sendbyte(&reply_message, requestReply ? 1 : 0);
 
 	/* Send it */
-	elog(DEBUG2, "sending write %X/%X flush %X/%X apply %X/%X%s",
+	elog(DEBUG2, "sending write %X/%08X flush %X/%08X apply %X/%08X%s",
 		 LSN_FORMAT_ARGS(writePtr),
 		 LSN_FORMAT_ARGS(flushPtr),
 		 LSN_FORMAT_ARGS(applyPtr),
diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c
index f2c33250e8b2f..ee911394a23c6 100644
--- a/src/backend/replication/walsender.c
+++ b/src/backend/replication/walsender.c
@@ -65,6 +65,7 @@
 #include "funcapi.h"
 #include "libpq/libpq.h"
 #include "libpq/pqformat.h"
+#include "libpq/protocol.h"
 #include "miscadmin.h"
 #include "nodes/replnodes.h"
 #include "pgstat.h"
@@ -84,6 +85,7 @@
 #include "storage/ipc.h"
 #include "storage/pmsignal.h"
 #include "storage/proc.h"
+#include "storage/procarray.h"
 #include "tcop/dest.h"
 #include "tcop/tcopprot.h"
 #include "utils/acl.h"
@@ -258,6 +260,7 @@ static void StartLogicalReplication(StartReplicationCmd *cmd);
 static void ProcessStandbyMessage(void);
 static void ProcessStandbyReplyMessage(void);
 static void ProcessStandbyHSFeedbackMessage(void);
+static void ProcessStandbyPSRequestMessage(void);
 static void ProcessRepliesIfAny(void);
 static void ProcessPendingWrites(void);
 static void WalSndKeepalive(bool requestReply, XLogRecPtr writePtr);
@@ -408,7 +411,7 @@ IdentifySystem(void)
 	else
 		logptr = GetFlushRecPtr(&currTLI);
 
-	snprintf(xloc, sizeof(xloc), "%X/%X", LSN_FORMAT_ARGS(logptr));
+	snprintf(xloc, sizeof(xloc), "%X/%08X", LSN_FORMAT_ARGS(logptr));
 
 	if (MyDatabaseId != InvalidOid)
 	{
@@ -515,7 +518,7 @@ ReadReplicationSlot(ReadReplicationSlotCmd *cmd)
 		{
 			char		xloc[64];
 
-			snprintf(xloc, sizeof(xloc), "%X/%X",
+			snprintf(xloc, sizeof(xloc), "%X/%08X",
 					 LSN_FORMAT_ARGS(slot_contents.data.restart_lsn));
 			values[i] = CStringGetTextDatum(xloc);
 			nulls[i] = false;
@@ -733,13 +736,13 @@ HandleUploadManifestPacket(StringInfo buf, off_t *offset,
 
 	switch (mtype)
 	{
-		case 'd':				/* CopyData */
+		case PqMsg_CopyData:
 			maxmsglen = PQ_LARGE_MESSAGE_LIMIT;
 			break;
-		case 'c':				/* CopyDone */
-		case 'f':				/* CopyFail */
-		case 'H':				/* Flush */
-		case 'S':				/* Sync */
+		case PqMsg_CopyDone:
+		case PqMsg_CopyFail:
+		case PqMsg_Flush:
+		case PqMsg_Sync:
 			maxmsglen = PQ_SMALL_MESSAGE_LIMIT;
 			break;
 		default:
@@ -761,19 +764,19 @@ HandleUploadManifestPacket(StringInfo buf, off_t *offset,
 	/* Process the message */
 	switch (mtype)
 	{
-		case 'd':				/* CopyData */
+		case PqMsg_CopyData:
 			AppendIncrementalManifestData(ib, buf->data, buf->len);
 			return true;
 
-		case 'c':				/* CopyDone */
+		case PqMsg_CopyDone:
 			return false;
 
-		case 'H':				/* Sync */
-		case 'S':				/* Flush */
+		case PqMsg_Sync:
+		case PqMsg_Flush:
 			/* Ignore these while in CopyOut mode as we do elsewhere. */
 			return true;
 
-		case 'f':
+		case PqMsg_CopyFail:
 			ereport(ERROR,
 					(errcode(ERRCODE_QUERY_CANCELED),
 					 errmsg("COPY from stdin failed: %s",
@@ -892,12 +895,12 @@ StartReplication(StartReplicationCmd *cmd)
 				switchpoint < cmd->startpoint)
 			{
 				ereport(ERROR,
-						(errmsg("requested starting point %X/%X on timeline %u is not in this server's history",
-								LSN_FORMAT_ARGS(cmd->startpoint),
-								cmd->timeline),
-						 errdetail("This server's history forked from timeline %u at %X/%X.",
-								   cmd->timeline,
-								   LSN_FORMAT_ARGS(switchpoint))));
+						errmsg("requested starting point %X/%08X on timeline %u is not in this server's history",
+							   LSN_FORMAT_ARGS(cmd->startpoint),
+							   cmd->timeline),
+						errdetail("This server's history forked from timeline %u at %X/%08X.",
+								  cmd->timeline,
+								  LSN_FORMAT_ARGS(switchpoint)));
 			}
 			sendTimeLineValidUpto = switchpoint;
 		}
@@ -939,9 +942,9 @@ StartReplication(StartReplicationCmd *cmd)
 		if (FlushPtr < cmd->startpoint)
 		{
 			ereport(ERROR,
-					(errmsg("requested starting point %X/%X is ahead of the WAL flush position of this server %X/%X",
-							LSN_FORMAT_ARGS(cmd->startpoint),
-							LSN_FORMAT_ARGS(FlushPtr))));
+					errmsg("requested starting point %X/%08X is ahead of the WAL flush position of this server %X/%08X",
+						   LSN_FORMAT_ARGS(cmd->startpoint),
+						   LSN_FORMAT_ARGS(FlushPtr)));
 		}
 
 		/* Start streaming from the requested point */
@@ -983,7 +986,7 @@ StartReplication(StartReplicationCmd *cmd)
 		Datum		values[2];
 		bool		nulls[2] = {0};
 
-		snprintf(startpos_str, sizeof(startpos_str), "%X/%X",
+		snprintf(startpos_str, sizeof(startpos_str), "%X/%08X",
 				 LSN_FORMAT_ARGS(sendTimeLineValidUpto));
 
 		dest = CreateDestReceiver(DestRemoteSimple);
@@ -1324,7 +1327,7 @@ CreateReplicationSlot(CreateReplicationSlotCmd *cmd)
 			ReplicationSlotPersist();
 	}
 
-	snprintf(xloc, sizeof(xloc), "%X/%X",
+	snprintf(xloc, sizeof(xloc), "%X/%08X",
 			 LSN_FORMAT_ARGS(MyReplicationSlot->data.confirmed_flush));
 
 	dest = CreateDestReceiver(DestRemoteSimple);
@@ -1567,7 +1570,7 @@ WalSndWriteData(LogicalDecodingContext *ctx, XLogRecPtr lsn, TransactionId xid,
 		   tmpbuf.data, sizeof(int64));
 
 	/* output previously gathered data in a CopyData packet */
-	pq_putmessage_noblock('d', ctx->out->data, ctx->out->len);
+	pq_putmessage_noblock(PqMsg_CopyData, ctx->out->data, ctx->out->len);
 
 	CHECK_FOR_INTERRUPTS();
 
@@ -2303,7 +2306,7 @@ ProcessRepliesIfAny(void)
 			case PqMsg_CopyDone:
 				if (!streamingDoneSending)
 				{
-					pq_putmessage_noblock('c', NULL, 0);
+					pq_putmessage_noblock(PqMsg_CopyDone, NULL, 0);
 					streamingDoneSending = true;
 				}
 
@@ -2355,6 +2358,10 @@ ProcessStandbyMessage(void)
 			ProcessStandbyHSFeedbackMessage();
 			break;
 
+		case 'p':
+			ProcessStandbyPSRequestMessage();
+			break;
+
 		default:
 			ereport(COMMERROR,
 					(errcode(ERRCODE_PROTOCOL_VIOLATION),
@@ -2429,7 +2436,7 @@ ProcessStandbyReplyMessage(void)
 		/* Copy because timestamptz_to_str returns a static buffer */
 		replyTimeStr = pstrdup(timestamptz_to_str(replyTime));
 
-		elog(DEBUG2, "write %X/%X flush %X/%X apply %X/%X%s reply_time %s",
+		elog(DEBUG2, "write %X/%08X flush %X/%08X apply %X/%08X%s reply_time %s",
 			 LSN_FORMAT_ARGS(writePtr),
 			 LSN_FORMAT_ARGS(flushPtr),
 			 LSN_FORMAT_ARGS(applyPtr),
@@ -2701,6 +2708,60 @@ ProcessStandbyHSFeedbackMessage(void)
 	}
 }
 
+/*
+ * Process the request for a primary status update message.
+ */
+static void
+ProcessStandbyPSRequestMessage(void)
+{
+	XLogRecPtr	lsn = InvalidXLogRecPtr;
+	TransactionId oldestXidInCommit;
+	FullTransactionId nextFullXid;
+	FullTransactionId fullOldestXidInCommit;
+	WalSnd	   *walsnd = MyWalSnd;
+	TimestampTz replyTime;
+
+	/*
+	 * This shouldn't happen because we don't support getting primary status
+	 * message from standby.
+	 */
+	if (RecoveryInProgress())
+		elog(ERROR, "the primary status is unavailable during recovery");
+
+	replyTime = pq_getmsgint64(&reply_message);
+
+	/*
+	 * Update shared state for this WalSender process based on reply data from
+	 * standby.
+	 */
+	SpinLockAcquire(&walsnd->mutex);
+	walsnd->replyTime = replyTime;
+	SpinLockRelease(&walsnd->mutex);
+
+	/*
+	 * Consider transactions in the current database, as only these are the
+	 * ones replicated.
+	 */
+	oldestXidInCommit = GetOldestActiveTransactionId(true, false);
+	nextFullXid = ReadNextFullTransactionId();
+	fullOldestXidInCommit = FullTransactionIdFromAllowableAt(nextFullXid,
+															 oldestXidInCommit);
+	lsn = GetXLogWriteRecPtr();
+
+	elog(DEBUG2, "sending primary status");
+
+	/* construct the message... */
+	resetStringInfo(&output_message);
+	pq_sendbyte(&output_message, 's');
+	pq_sendint64(&output_message, lsn);
+	pq_sendint64(&output_message, (int64) U64FromFullTransactionId(fullOldestXidInCommit));
+	pq_sendint64(&output_message, (int64) U64FromFullTransactionId(nextFullXid));
+	pq_sendint64(&output_message, GetCurrentTimestamp());
+
+	/* ... and send it wrapped in CopyData */
+	pq_putmessage_noblock(PqMsg_CopyData, output_message.data, output_message.len);
+}
+
 /*
  * Compute how long send/receive loops should sleep.
  *
@@ -3246,12 +3307,12 @@ XLogSendPhysical(void)
 			wal_segment_close(xlogreader);
 
 		/* Send CopyDone */
-		pq_putmessage_noblock('c', NULL, 0);
+		pq_putmessage_noblock(PqMsg_CopyDone, NULL, 0);
 		streamingDoneSending = true;
 
 		WalSndCaughtUp = true;
 
-		elog(DEBUG1, "walsender reached end of timeline at %X/%X (sent up to %X/%X)",
+		elog(DEBUG1, "walsender reached end of timeline at %X/%08X (sent up to %X/%08X)",
 			 LSN_FORMAT_ARGS(sendTimeLineValidUpto),
 			 LSN_FORMAT_ARGS(sentPtr));
 		return;
@@ -3374,7 +3435,7 @@ XLogSendPhysical(void)
 	memcpy(&output_message.data[1 + sizeof(int64) + sizeof(int64)],
 		   tmpbuf.data, sizeof(int64));
 
-	pq_putmessage_noblock('d', output_message.data, output_message.len);
+	pq_putmessage_noblock(PqMsg_CopyData, output_message.data, output_message.len);
 
 	sentPtr = endptr;
 
@@ -3392,7 +3453,7 @@ XLogSendPhysical(void)
 	{
 		char		activitymsg[50];
 
-		snprintf(activitymsg, sizeof(activitymsg), "streaming %X/%X",
+		snprintf(activitymsg, sizeof(activitymsg), "streaming %X/%08X",
 				 LSN_FORMAT_ARGS(sentPtr));
 		set_ps_display(activitymsg);
 	}
@@ -4080,7 +4141,7 @@ WalSndKeepalive(bool requestReply, XLogRecPtr writePtr)
 	pq_sendbyte(&output_message, requestReply ? 1 : 0);
 
 	/* ... and send it wrapped in CopyData */
-	pq_putmessage_noblock('d', output_message.data, output_message.len);
+	pq_putmessage_noblock(PqMsg_CopyData, output_message.data, output_message.len);
 
 	/* Set local flag */
 	if (requestReply)
diff --git a/src/backend/rewrite/rewriteHandler.c b/src/backend/rewrite/rewriteHandler.c
index 2ef0e7fbf3a69..adc9e7600e1ed 100644
--- a/src/backend/rewrite/rewriteHandler.c
+++ b/src/backend/rewrite/rewriteHandler.c
@@ -923,8 +923,9 @@ rewriteTargetListIU(List *targetList,
 				apply_default = true;
 
 			/*
-			 * Can only insert DEFAULT into generated columns, regardless of
-			 * any OVERRIDING clauses.
+			 * Can only insert DEFAULT into generated columns.  (The
+			 * OVERRIDING clause does not apply to generated columns, so we
+			 * don't consider it here.)
 			 */
 			if (att_tup->attgenerated && !apply_default)
 			{
diff --git a/src/backend/statistics/mcv.c b/src/backend/statistics/mcv.c
index d98cda698d941..f59fb82154370 100644
--- a/src/backend/statistics/mcv.c
+++ b/src/backend/statistics/mcv.c
@@ -767,7 +767,7 @@ statext_mcv_serialize(MCVList *mcvlist, VacAttrStats **stats)
 				values[dim][i] = PointerGetDatum(PG_DETOAST_DATUM(values[dim][i]));
 
 				/* serialized length (uint32 length + data) */
-				len = VARSIZE_ANY_EXHDR(values[dim][i]);
+				len = VARSIZE_ANY_EXHDR(DatumGetPointer(values[dim][i]));
 				info[dim].nbytes += sizeof(uint32); /* length */
 				info[dim].nbytes += len;	/* value (no header) */
 
diff --git a/src/backend/storage/aio/README.md b/src/backend/storage/aio/README.md
index f10b5c7e31ec7..72ae3b3737d51 100644
--- a/src/backend/storage/aio/README.md
+++ b/src/backend/storage/aio/README.md
@@ -94,7 +94,7 @@ pgaio_io_register_callbacks(ioh, PGAIO_HCB_SHARED_BUFFER_READV, 0);
  *
  * In this example we're reading only a single buffer, hence the 1.
  */
-pgaio_io_set_handle_data_32(ioh, (uint32 *) buffer, 1);
+pgaio_io_set_handle_data_32(ioh, (uint32 *) &buffer, 1);
 
 /*
  * Pass the AIO handle to lower-level function. When operating on the level of
@@ -119,8 +119,9 @@ pgaio_io_set_handle_data_32(ioh, (uint32 *) buffer, 1);
  * e.g. due to reaching a limit on the number of unsubmitted IOs, and even
  * complete before smgrstartreadv() returns.
  */
+void *page = BufferGetBlock(buffer);
 smgrstartreadv(ioh, operation->smgr, forknum, blkno,
-               BufferGetBlock(buffer), 1);
+               &page, 1);
 
 /*
  * To benefit from AIO, it is beneficial to perform other work, including
diff --git a/src/backend/storage/aio/method_io_uring.c b/src/backend/storage/aio/method_io_uring.c
index b78048328e113..0a8c054162f06 100644
--- a/src/backend/storage/aio/method_io_uring.c
+++ b/src/backend/storage/aio/method_io_uring.c
@@ -29,6 +29,9 @@
 
 #ifdef IOMETHOD_IO_URING_ENABLED
 
+#include <sys/mman.h>
+#include <unistd.h>
+
 #include <liburing.h>
 
 #include "miscadmin.h"
@@ -94,12 +97,32 @@ PgAioUringContext
 	struct io_uring io_uring_ring;
 } PgAioUringContext;
 
+/*
+ * Information about the capabilities that io_uring has.
+ *
+ * Depending on liburing and kernel version different features are
+ * supported. At least for the kernel a kernel version check does not suffice
+ * as various vendors do backport features to older kernels :(.
+ */
+typedef struct PgAioUringCaps
+{
+	bool		checked;
+	/* -1 if io_uring_queue_init_mem() is unsupported */
+	int			mem_init_size;
+} PgAioUringCaps;
+
+
 /* PgAioUringContexts for all backends */
 static PgAioUringContext *pgaio_uring_contexts;
 
 /* the current backend's context */
 static PgAioUringContext *pgaio_my_uring_context;
 
+static PgAioUringCaps pgaio_uring_caps =
+{
+	.checked = false,
+	.mem_init_size = -1,
+};
 
 static uint32
 pgaio_uring_procs(void)
@@ -111,16 +134,145 @@ pgaio_uring_procs(void)
 	return MaxBackends + NUM_AUXILIARY_PROCS - MAX_IO_WORKERS;
 }
 
-static Size
+/*
+ * Initializes pgaio_uring_caps, unless that's already done.
+ */
+static void
+pgaio_uring_check_capabilities(void)
+{
+	if (pgaio_uring_caps.checked)
+		return;
+
+	/*
+	 * By default io_uring creates a shared memory mapping for each io_uring
+	 * instance, leading to a large number of memory mappings. Unfortunately a
+	 * large number of memory mappings slows things down, backend exit is
+	 * particularly affected.  To address that, newer kernels (6.5) support
+	 * using user-provided memory for the memory, by putting the relevant
+	 * memory into shared memory we don't need any additional mappings.
+	 *
+	 * To know whether this is supported, we unfortunately need to probe the
+	 * kernel by trying to create a ring with userspace-provided memory. This
+	 * also has a secondary benefit: We can determine precisely how much
+	 * memory we need for each io_uring instance.
+	 */
+#if defined(HAVE_LIBURING_QUEUE_INIT_MEM) && defined(IORING_SETUP_NO_MMAP)
+	{
+		struct io_uring test_ring;
+		size_t		ring_size;
+		void	   *ring_ptr;
+		struct io_uring_params p = {0};
+		int			ret;
+
+		/*
+		 * Liburing does not yet provide an API to query how much memory a
+		 * ring will need. So we over-estimate it here. As the memory is freed
+		 * just below that's small temporary waste of memory.
+		 *
+		 * 1MB is more than enough for rings within io_max_concurrency's
+		 * range.
+		 */
+		ring_size = 1024 * 1024;
+
+		/*
+		 * Hard to believe a system exists where 1MB would not be a multiple
+		 * of the page size. But it's cheap to ensure...
+		 */
+		ring_size -= ring_size % sysconf(_SC_PAGESIZE);
+
+		ring_ptr = mmap(NULL, ring_size, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0);
+		if (ring_ptr == MAP_FAILED)
+			elog(ERROR,
+				 "mmap(%zu) to determine io_uring_queue_init_mem() support failed: %m",
+				 ring_size);
+
+		ret = io_uring_queue_init_mem(io_max_concurrency, &test_ring, &p, ring_ptr, ring_size);
+		if (ret > 0)
+		{
+			pgaio_uring_caps.mem_init_size = ret;
+
+			elog(DEBUG1,
+				 "can use combined memory mapping for io_uring, each ring needs %d bytes",
+				 ret);
+
+			/* clean up the created ring, it was just for a test */
+			io_uring_queue_exit(&test_ring);
+		}
+		else
+		{
+			/*
+			 * There are different reasons for ring creation to fail, but it's
+			 * ok to treat that just as io_uring_queue_init_mem() not being
+			 * supported. We'll report a more detailed error in
+			 * pgaio_uring_shmem_init().
+			 */
+			errno = -ret;
+			elog(DEBUG1,
+				 "cannot use combined memory mapping for io_uring, ring creation failed: %m");
+
+		}
+
+		if (munmap(ring_ptr, ring_size) != 0)
+			elog(ERROR, "munmap() failed: %m");
+	}
+#else
+	{
+		elog(DEBUG1,
+			 "can't use combined memory mapping for io_uring, kernel or liburing too old");
+	}
+#endif
+
+	pgaio_uring_caps.checked = true;
+}
+
+/*
+ * Memory for all PgAioUringContext instances
+ */
+static size_t
 pgaio_uring_context_shmem_size(void)
 {
 	return mul_size(pgaio_uring_procs(), sizeof(PgAioUringContext));
 }
 
+/*
+ * Memory for the combined memory used by io_uring instances. Returns 0 if
+ * that is not supported by kernel/liburing.
+ */
+static size_t
+pgaio_uring_ring_shmem_size(void)
+{
+	size_t		sz = 0;
+
+	if (pgaio_uring_caps.mem_init_size > 0)
+	{
+		/*
+		 * Memory for rings needs to be allocated to the page boundary,
+		 * reserve space. Luckily it does not need to be aligned to hugepage
+		 * boundaries, even if huge pages are used.
+		 */
+		sz = add_size(sz, sysconf(_SC_PAGESIZE));
+		sz = add_size(sz, mul_size(pgaio_uring_procs(),
+								   pgaio_uring_caps.mem_init_size));
+	}
+
+	return sz;
+}
+
 static size_t
 pgaio_uring_shmem_size(void)
 {
-	return pgaio_uring_context_shmem_size();
+	size_t		sz;
+
+	/*
+	 * Kernel and liburing support for various features influences how much
+	 * shmem we need, perform the necessary checks.
+	 */
+	pgaio_uring_check_capabilities();
+
+	sz = pgaio_uring_context_shmem_size();
+	sz = add_size(sz, pgaio_uring_ring_shmem_size());
+
+	return sz;
 }
 
 static void
@@ -128,13 +280,38 @@ pgaio_uring_shmem_init(bool first_time)
 {
 	int			TotalProcs = pgaio_uring_procs();
 	bool		found;
+	char	   *shmem;
+	size_t		ring_mem_remain = 0;
+	char	   *ring_mem_next = 0;
 
-	pgaio_uring_contexts = (PgAioUringContext *)
-		ShmemInitStruct("AioUring", pgaio_uring_shmem_size(), &found);
-
+	/*
+	 * We allocate memory for all PgAioUringContext instances and, if
+	 * supported, the memory required for each of the io_uring instances, in
+	 * one ShmemInitStruct().
+	 */
+	shmem = ShmemInitStruct("AioUringContext", pgaio_uring_shmem_size(), &found);
 	if (found)
 		return;
 
+	pgaio_uring_contexts = (PgAioUringContext *) shmem;
+	shmem += pgaio_uring_context_shmem_size();
+
+	/* if supported, handle memory alignment / sizing for io_uring memory */
+	if (pgaio_uring_caps.mem_init_size > 0)
+	{
+		ring_mem_remain = pgaio_uring_ring_shmem_size();
+		ring_mem_next = (char *) shmem;
+
+		/* align to page boundary, see also pgaio_uring_ring_shmem_size() */
+		ring_mem_next = (char *) TYPEALIGN(sysconf(_SC_PAGESIZE), ring_mem_next);
+
+		/* account for alignment */
+		ring_mem_remain -= ring_mem_next - shmem;
+		shmem += ring_mem_next - shmem;
+
+		shmem += ring_mem_remain;
+	}
+
 	for (int contextno = 0; contextno < TotalProcs; contextno++)
 	{
 		PgAioUringContext *context = &pgaio_uring_contexts[contextno];
@@ -158,7 +335,28 @@ pgaio_uring_shmem_init(bool first_time)
 		 * be worth using that - also need to evaluate if that causes
 		 * noticeable additional contention?
 		 */
-		ret = io_uring_queue_init(io_max_concurrency, &context->io_uring_ring, 0);
+
+		/*
+		 * If supported (c.f. pgaio_uring_check_capabilities()), create ring
+		 * with its data in shared memory. Otherwise fall back io_uring
+		 * creating a memory mapping for each ring.
+		 */
+#if defined(HAVE_LIBURING_QUEUE_INIT_MEM) && defined(IORING_SETUP_NO_MMAP)
+		if (pgaio_uring_caps.mem_init_size > 0)
+		{
+			struct io_uring_params p = {0};
+
+			ret = io_uring_queue_init_mem(io_max_concurrency, &context->io_uring_ring, &p, ring_mem_next, ring_mem_remain);
+
+			ring_mem_remain -= ret;
+			ring_mem_next += ret;
+		}
+		else
+#endif
+		{
+			ret = io_uring_queue_init(io_max_concurrency, &context->io_uring_ring, 0);
+		}
+
 		if (ret < 0)
 		{
 			char	   *hint = NULL;
diff --git a/src/backend/storage/aio/method_worker.c b/src/backend/storage/aio/method_worker.c
index 36be179678d7a..bf8f77e6ff606 100644
--- a/src/backend/storage/aio/method_worker.c
+++ b/src/backend/storage/aio/method_worker.c
@@ -52,26 +52,26 @@
 #define IO_WORKER_WAKEUP_FANOUT 2
 
 
-typedef struct AioWorkerSubmissionQueue
+typedef struct PgAioWorkerSubmissionQueue
 {
 	uint32		size;
 	uint32		mask;
 	uint32		head;
 	uint32		tail;
-	uint32		ios[FLEXIBLE_ARRAY_MEMBER];
-} AioWorkerSubmissionQueue;
+	uint32		sqes[FLEXIBLE_ARRAY_MEMBER];
+} PgAioWorkerSubmissionQueue;
 
-typedef struct AioWorkerSlot
+typedef struct PgAioWorkerSlot
 {
 	Latch	   *latch;
 	bool		in_use;
-} AioWorkerSlot;
+} PgAioWorkerSlot;
 
-typedef struct AioWorkerControl
+typedef struct PgAioWorkerControl
 {
 	uint64		idle_worker_mask;
-	AioWorkerSlot workers[FLEXIBLE_ARRAY_MEMBER];
-} AioWorkerControl;
+	PgAioWorkerSlot workers[FLEXIBLE_ARRAY_MEMBER];
+} PgAioWorkerControl;
 
 
 static size_t pgaio_worker_shmem_size(void);
@@ -96,8 +96,8 @@ int			io_workers = 3;
 
 static int	io_worker_queue_size = 64;
 static int	MyIoWorkerId;
-static AioWorkerSubmissionQueue *io_worker_submission_queue;
-static AioWorkerControl *io_worker_control;
+static PgAioWorkerSubmissionQueue *io_worker_submission_queue;
+static PgAioWorkerControl *io_worker_control;
 
 
 static size_t
@@ -106,15 +106,15 @@ pgaio_worker_queue_shmem_size(int *queue_size)
 	/* Round size up to next power of two so we can make a mask. */
 	*queue_size = pg_nextpower2_32(io_worker_queue_size);
 
-	return offsetof(AioWorkerSubmissionQueue, ios) +
+	return offsetof(PgAioWorkerSubmissionQueue, sqes) +
 		sizeof(uint32) * *queue_size;
 }
 
 static size_t
 pgaio_worker_control_shmem_size(void)
 {
-	return offsetof(AioWorkerControl, workers) +
-		sizeof(AioWorkerSlot) * MAX_IO_WORKERS;
+	return offsetof(PgAioWorkerControl, workers) +
+		sizeof(PgAioWorkerSlot) * MAX_IO_WORKERS;
 }
 
 static size_t
@@ -162,7 +162,7 @@ pgaio_worker_shmem_init(bool first_time)
 }
 
 static int
-pgaio_choose_idle_worker(void)
+pgaio_worker_choose_idle(void)
 {
 	int			worker;
 
@@ -172,6 +172,7 @@ pgaio_choose_idle_worker(void)
 	/* Find the lowest bit position, and clear it. */
 	worker = pg_rightmost_one_pos64(io_worker_control->idle_worker_mask);
 	io_worker_control->idle_worker_mask &= ~(UINT64_C(1) << worker);
+	Assert(io_worker_control->workers[worker].in_use);
 
 	return worker;
 }
@@ -179,7 +180,7 @@ pgaio_choose_idle_worker(void)
 static bool
 pgaio_worker_submission_queue_insert(PgAioHandle *ioh)
 {
-	AioWorkerSubmissionQueue *queue;
+	PgAioWorkerSubmissionQueue *queue;
 	uint32		new_head;
 
 	queue = io_worker_submission_queue;
@@ -191,7 +192,7 @@ pgaio_worker_submission_queue_insert(PgAioHandle *ioh)
 		return false;			/* full */
 	}
 
-	queue->ios[queue->head] = pgaio_io_get_id(ioh);
+	queue->sqes[queue->head] = pgaio_io_get_id(ioh);
 	queue->head = new_head;
 
 	return true;
@@ -200,14 +201,14 @@ pgaio_worker_submission_queue_insert(PgAioHandle *ioh)
 static uint32
 pgaio_worker_submission_queue_consume(void)
 {
-	AioWorkerSubmissionQueue *queue;
+	PgAioWorkerSubmissionQueue *queue;
 	uint32		result;
 
 	queue = io_worker_submission_queue;
 	if (queue->tail == queue->head)
 		return UINT32_MAX;		/* empty */
 
-	result = queue->ios[queue->tail];
+	result = queue->sqes[queue->tail];
 	queue->tail = (queue->tail + 1) & (queue->size - 1);
 
 	return result;
@@ -240,37 +241,37 @@ pgaio_worker_needs_synchronous_execution(PgAioHandle *ioh)
 }
 
 static void
-pgaio_worker_submit_internal(int nios, PgAioHandle *ios[])
+pgaio_worker_submit_internal(int num_staged_ios, PgAioHandle **staged_ios)
 {
 	PgAioHandle *synchronous_ios[PGAIO_SUBMIT_BATCH_SIZE];
 	int			nsync = 0;
 	Latch	   *wakeup = NULL;
 	int			worker;
 
-	Assert(nios <= PGAIO_SUBMIT_BATCH_SIZE);
+	Assert(num_staged_ios <= PGAIO_SUBMIT_BATCH_SIZE);
 
 	LWLockAcquire(AioWorkerSubmissionQueueLock, LW_EXCLUSIVE);
-	for (int i = 0; i < nios; ++i)
+	for (int i = 0; i < num_staged_ios; ++i)
 	{
-		Assert(!pgaio_worker_needs_synchronous_execution(ios[i]));
-		if (!pgaio_worker_submission_queue_insert(ios[i]))
+		Assert(!pgaio_worker_needs_synchronous_execution(staged_ios[i]));
+		if (!pgaio_worker_submission_queue_insert(staged_ios[i]))
 		{
 			/*
 			 * We'll do it synchronously, but only after we've sent as many as
 			 * we can to workers, to maximize concurrency.
 			 */
-			synchronous_ios[nsync++] = ios[i];
+			synchronous_ios[nsync++] = staged_ios[i];
 			continue;
 		}
 
 		if (wakeup == NULL)
 		{
 			/* Choose an idle worker to wake up if we haven't already. */
-			worker = pgaio_choose_idle_worker();
+			worker = pgaio_worker_choose_idle();
 			if (worker >= 0)
 				wakeup = io_worker_control->workers[worker].latch;
 
-			pgaio_debug_io(DEBUG4, ios[i],
+			pgaio_debug_io(DEBUG4, staged_ios[i],
 						   "choosing worker %d",
 						   worker);
 		}
@@ -316,6 +317,7 @@ pgaio_worker_die(int code, Datum arg)
 	Assert(io_worker_control->workers[MyIoWorkerId].in_use);
 	Assert(io_worker_control->workers[MyIoWorkerId].latch == MyLatch);
 
+	io_worker_control->idle_worker_mask &= ~(UINT64_C(1) << MyIoWorkerId);
 	io_worker_control->workers[MyIoWorkerId].in_use = false;
 	io_worker_control->workers[MyIoWorkerId].latch = NULL;
 	LWLockRelease(AioWorkerSubmissionQueueLock);
@@ -488,7 +490,7 @@ IoWorkerMain(const void *startup_data, size_t startup_data_len)
 						   IO_WORKER_WAKEUP_FANOUT);
 			for (int i = 0; i < nwakeups; ++i)
 			{
-				if ((worker = pgaio_choose_idle_worker()) < 0)
+				if ((worker = pgaio_worker_choose_idle()) < 0)
 					break;
 				latches[nlatches++] = io_worker_control->workers[worker].latch;
 			}
@@ -573,6 +575,12 @@ IoWorkerMain(const void *startup_data, size_t startup_data_len)
 		}
 
 		CHECK_FOR_INTERRUPTS();
+
+		if (ConfigReloadPending)
+		{
+			ConfigReloadPending = false;
+			ProcessConfigFile(PGC_SIGHUP);
+		}
 	}
 
 	error_context_stack = errcallback.previous;
diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index 667aa0c0c78d4..67431208e7f5f 100644
--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@@ -2743,12 +2743,10 @@ ExtendBufferedRelShared(BufferManagerRelation bmr,
 		 * because mdread doesn't complain about reads beyond EOF (when
 		 * zero_damaged_pages is ON) and so a previous attempt to read a block
 		 * beyond EOF could have left a "valid" zero-filled buffer.
-		 * Unfortunately, we have also seen this case occurring because of
-		 * buggy Linux kernels that sometimes return an lseek(SEEK_END) result
-		 * that doesn't account for a recent write. In that situation, the
-		 * pre-existing buffer would contain valid data that we don't want to
-		 * overwrite.  Since the legitimate cases should always have left a
-		 * zero-filled buffer, complain if not PageIsNew.
+		 *
+		 * This has also been observed when relation was overwritten by
+		 * external process. Since the legitimate cases should always have
+		 * left a zero-filled buffer, complain if not PageIsNew.
 		 */
 		if (existing_id >= 0)
 		{
@@ -2778,8 +2776,7 @@ ExtendBufferedRelShared(BufferManagerRelation bmr,
 				ereport(ERROR,
 						(errmsg("unexpected data beyond EOF in block %u of relation %s",
 								existing_hdr->tag.blockNum,
-								relpath(bmr.smgr->smgr_rlocator, fork).str),
-						 errhint("This has been seen to occur with buggy kernels; consider updating your system.")));
+								relpath(bmr.smgr->smgr_rlocator, fork).str)));
 
 			/*
 			 * We *must* do smgr[zero]extend before succeeding, else the page
@@ -3339,10 +3336,10 @@ UnpinBufferNoOwner(BufferDesc *buf)
  * BufferSync -- Write out all dirty buffers in the pool.
  *
  * This is called at checkpoint time to write out all dirty shared buffers.
- * The checkpoint request flags should be passed in.  If CHECKPOINT_IMMEDIATE
- * is set, we disable delays between writes; if CHECKPOINT_IS_SHUTDOWN,
- * CHECKPOINT_END_OF_RECOVERY or CHECKPOINT_FLUSH_ALL is set, we write even
- * unlogged buffers, which are otherwise skipped.  The remaining flags
+ * The checkpoint request flags should be passed in.  If CHECKPOINT_FAST is
+ * set, we disable delays between writes; if CHECKPOINT_IS_SHUTDOWN,
+ * CHECKPOINT_END_OF_RECOVERY or CHECKPOINT_FLUSH_UNLOGGED is set, we write
+ * even unlogged buffers, which are otherwise skipped.  The remaining flags
  * currently have no effect here.
  */
 static void
@@ -3367,7 +3364,7 @@ BufferSync(int flags)
 	 * recovery, we write all dirty buffers.
 	 */
 	if (!((flags & (CHECKPOINT_IS_SHUTDOWN | CHECKPOINT_END_OF_RECOVERY |
-					CHECKPOINT_FLUSH_ALL))))
+					CHECKPOINT_FLUSH_UNLOGGED))))
 		mask |= BM_PERMANENT;
 
 	/*
@@ -4550,11 +4547,9 @@ DropRelationBuffers(SMgrRelation smgr_reln, ForkNumber *forkNum,
 	if (RelFileLocatorBackendIsTemp(rlocator))
 	{
 		if (rlocator.backend == MyProcNumber)
-		{
-			for (j = 0; j < nforks; j++)
-				DropRelationLocalBuffers(rlocator.locator, forkNum[j],
-										 firstDelBlock[j]);
-		}
+			DropRelationLocalBuffers(rlocator.locator, forkNum, nforks,
+									 firstDelBlock);
+
 		return;
 	}
 
diff --git a/src/backend/storage/buffer/localbuf.c b/src/backend/storage/buffer/localbuf.c
index ba26627f7b00d..3c0d20f4659d2 100644
--- a/src/backend/storage/buffer/localbuf.c
+++ b/src/backend/storage/buffer/localbuf.c
@@ -660,10 +660,11 @@ InvalidateLocalBuffer(BufferDesc *bufHdr, bool check_unreferenced)
  *		See DropRelationBuffers in bufmgr.c for more notes.
  */
 void
-DropRelationLocalBuffers(RelFileLocator rlocator, ForkNumber forkNum,
-						 BlockNumber firstDelBlock)
+DropRelationLocalBuffers(RelFileLocator rlocator, ForkNumber *forkNum,
+						 int nforks, BlockNumber *firstDelBlock)
 {
 	int			i;
+	int			j;
 
 	for (i = 0; i < NLocBuffer; i++)
 	{
@@ -672,12 +673,18 @@ DropRelationLocalBuffers(RelFileLocator rlocator, ForkNumber forkNum,
 
 		buf_state = pg_atomic_read_u32(&bufHdr->state);
 
-		if ((buf_state & BM_TAG_VALID) &&
-			BufTagMatchesRelFileLocator(&bufHdr->tag, &rlocator) &&
-			BufTagGetForkNum(&bufHdr->tag) == forkNum &&
-			bufHdr->tag.blockNum >= firstDelBlock)
+		if (!(buf_state & BM_TAG_VALID) ||
+			!BufTagMatchesRelFileLocator(&bufHdr->tag, &rlocator))
+			continue;
+
+		for (j = 0; j < nforks; j++)
 		{
-			InvalidateLocalBuffer(bufHdr, true);
+			if (BufTagGetForkNum(&bufHdr->tag) == forkNum[j] &&
+				bufHdr->tag.blockNum >= firstDelBlock[j])
+			{
+				InvalidateLocalBuffer(bufHdr, true);
+				break;
+			}
 		}
 	}
 }
@@ -925,10 +932,11 @@ GetLocalBufferStorage(void)
 		num_bufs = Min(num_bufs, MaxAllocSize / BLCKSZ);
 
 		/* Buffers should be I/O aligned. */
-		cur_block = (char *)
-			TYPEALIGN(PG_IO_ALIGN_SIZE,
-					  MemoryContextAlloc(LocalBufferContext,
-										 num_bufs * BLCKSZ + PG_IO_ALIGN_SIZE));
+		cur_block = MemoryContextAllocAligned(LocalBufferContext,
+											  num_bufs * BLCKSZ,
+											  PG_IO_ALIGN_SIZE,
+											  0);
+
 		next_buf_in_block = 0;
 		num_bufs_in_block = num_bufs;
 	}
diff --git a/src/backend/storage/file/fd.c b/src/backend/storage/file/fd.c
index 0e8299dd55646..a4ec7959f31cf 100644
--- a/src/backend/storage/file/fd.c
+++ b/src/backend/storage/file/fd.c
@@ -400,25 +400,22 @@ pg_fsync(int fd)
 	 * portable, even if it runs ok on the current system.
 	 *
 	 * We assert here that a descriptor for a file was opened with write
-	 * permissions (either O_RDWR or O_WRONLY) and for a directory without
-	 * write permissions (O_RDONLY).
+	 * permissions (i.e., not O_RDONLY) and for a directory without write
+	 * permissions (O_RDONLY).  Notice that the assertion check is made even
+	 * if fsync() is disabled.
 	 *
-	 * Ignore any fstat errors and let the follow-up fsync() do its work.
-	 * Doing this sanity check here counts for the case where fsync() is
-	 * disabled.
+	 * If fstat() fails, ignore it and let the follow-up fsync() complain.
 	 */
 	if (fstat(fd, &st) == 0)
 	{
 		int			desc_flags = fcntl(fd, F_GETFL);
 
-		/*
-		 * O_RDONLY is historically 0, so just make sure that for directories
-		 * no write flags are used.
-		 */
+		desc_flags &= O_ACCMODE;
+
 		if (S_ISDIR(st.st_mode))
-			Assert((desc_flags & (O_RDWR | O_WRONLY)) == 0);
+			Assert(desc_flags == O_RDONLY);
 		else
-			Assert((desc_flags & (O_RDWR | O_WRONLY)) != 0);
+			Assert(desc_flags != O_RDONLY);
 	}
 	errno = 0;
 #endif
diff --git a/src/backend/storage/file/fileset.c b/src/backend/storage/file/fileset.c
index 64141c7cb91c9..4d5ee353fd7a0 100644
--- a/src/backend/storage/file/fileset.c
+++ b/src/backend/storage/file/fileset.c
@@ -185,7 +185,7 @@ FileSetPath(char *path, FileSet *fileset, Oid tablespace)
 static Oid
 ChooseTablespace(const FileSet *fileset, const char *name)
 {
-	uint32		hash = hash_any((const unsigned char *) name, strlen(name));
+	uint32		hash = hash_bytes((const unsigned char *) name, strlen(name));
 
 	return fileset->tablespaces[hash % fileset->ntablespaces];
 }
diff --git a/src/backend/storage/ipc/dsm_registry.c b/src/backend/storage/ipc/dsm_registry.c
index 1d4fd31ffedbc..1682cc6d34c7f 100644
--- a/src/backend/storage/ipc/dsm_registry.c
+++ b/src/backend/storage/ipc/dsm_registry.c
@@ -15,6 +15,20 @@
  * current backend.  This function guarantees that only one backend
  * initializes the segment and that all other backends just attach it.
  *
+ * A DSA can be created in or retrieved from the registry by calling
+ * GetNamedDSA().  As with GetNamedDSMSegment(), if a DSA with the provided
+ * name does not yet exist, it is created.  Otherwise, GetNamedDSA()
+ * ensures the DSA is attached to the current backend.  This function
+ * guarantees that only one backend initializes the DSA and that all other
+ * backends just attach it.
+ *
+ * A dshash table can be created in or retrieved from the registry by
+ * calling GetNamedDSHash().  As with GetNamedDSMSegment(), if a hash
+ * table with the provided name does not yet exist, it is created.
+ * Otherwise, GetNamedDSHash() ensures the hash table is attached to the
+ * current backend.  This function guarantees that only one backend
+ * initializes the table and that all other backends just attach it.
+ *
  * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
@@ -26,12 +40,20 @@
 
 #include "postgres.h"
 
+#include "funcapi.h"
 #include "lib/dshash.h"
 #include "storage/dsm_registry.h"
 #include "storage/lwlock.h"
 #include "storage/shmem.h"
+#include "utils/builtins.h"
 #include "utils/memutils.h"
 
+#define DSMR_NAME_LEN				128
+
+#define DSMR_DSA_TRANCHE_SUFFIX		" DSA"
+#define DSMR_DSA_TRANCHE_SUFFIX_LEN (sizeof(DSMR_DSA_TRANCHE_SUFFIX) - 1)
+#define DSMR_DSA_TRANCHE_NAME_LEN	(DSMR_NAME_LEN + DSMR_DSA_TRANCHE_SUFFIX_LEN)
+
 typedef struct DSMRegistryCtxStruct
 {
 	dsa_handle	dsah;
@@ -40,15 +62,55 @@ typedef struct DSMRegistryCtxStruct
 
 static DSMRegistryCtxStruct *DSMRegistryCtx;
 
-typedef struct DSMRegistryEntry
+typedef struct NamedDSMState
 {
-	char		name[64];
 	dsm_handle	handle;
 	size_t		size;
+} NamedDSMState;
+
+typedef struct NamedDSAState
+{
+	dsa_handle	handle;
+	int			tranche;
+	char		tranche_name[DSMR_DSA_TRANCHE_NAME_LEN];
+} NamedDSAState;
+
+typedef struct NamedDSHState
+{
+	NamedDSAState dsa;
+	dshash_table_handle handle;
+	int			tranche;
+	char		tranche_name[DSMR_NAME_LEN];
+} NamedDSHState;
+
+typedef enum DSMREntryType
+{
+	DSMR_ENTRY_TYPE_DSM,
+	DSMR_ENTRY_TYPE_DSA,
+	DSMR_ENTRY_TYPE_DSH,
+} DSMREntryType;
+
+static const char *const DSMREntryTypeNames[] =
+{
+	[DSMR_ENTRY_TYPE_DSM] = "segment",
+	[DSMR_ENTRY_TYPE_DSA] = "area",
+	[DSMR_ENTRY_TYPE_DSH] = "hash",
+};
+
+typedef struct DSMRegistryEntry
+{
+	char		name[DSMR_NAME_LEN];
+	DSMREntryType type;
+	union
+	{
+		NamedDSMState dsm;
+		NamedDSAState dsa;
+		NamedDSHState dsh;
+	}			data;
 } DSMRegistryEntry;
 
 static const dshash_parameters dsh_params = {
-	offsetof(DSMRegistryEntry, handle),
+	offsetof(DSMRegistryEntry, type),
 	sizeof(DSMRegistryEntry),
 	dshash_strcmp,
 	dshash_strhash,
@@ -141,7 +203,7 @@ GetNamedDSMSegment(const char *name, size_t size,
 		ereport(ERROR,
 				(errmsg("DSM segment name cannot be empty")));
 
-	if (strlen(name) >= offsetof(DSMRegistryEntry, handle))
+	if (strlen(name) >= offsetof(DSMRegistryEntry, type))
 		ereport(ERROR,
 				(errmsg("DSM segment name too long")));
 
@@ -158,32 +220,39 @@ GetNamedDSMSegment(const char *name, size_t size,
 	entry = dshash_find_or_insert(dsm_registry_table, name, found);
 	if (!(*found))
 	{
+		NamedDSMState *state = &entry->data.dsm;
+		dsm_segment *seg;
+
+		entry->type = DSMR_ENTRY_TYPE_DSM;
+
 		/* Initialize the segment. */
-		dsm_segment *seg = dsm_create(size, 0);
+		seg = dsm_create(size, 0);
 
 		dsm_pin_segment(seg);
 		dsm_pin_mapping(seg);
-		entry->handle = dsm_segment_handle(seg);
-		entry->size = size;
+		state->handle = dsm_segment_handle(seg);
+		state->size = size;
 		ret = dsm_segment_address(seg);
 
 		if (init_callback)
 			(*init_callback) (ret);
 	}
-	else if (entry->size != size)
-	{
+	else if (entry->type != DSMR_ENTRY_TYPE_DSM)
 		ereport(ERROR,
-				(errmsg("requested DSM segment size does not match size of "
-						"existing segment")));
-	}
+				(errmsg("requested DSM segment does not match type of existing entry")));
+	else if (entry->data.dsm.size != size)
+		ereport(ERROR,
+				(errmsg("requested DSM segment size does not match size of existing segment")));
 	else
 	{
-		dsm_segment *seg = dsm_find_mapping(entry->handle);
+		NamedDSMState *state = &entry->data.dsm;
+		dsm_segment *seg;
 
 		/* If the existing segment is not already attached, attach it now. */
+		seg = dsm_find_mapping(state->handle);
 		if (seg == NULL)
 		{
-			seg = dsm_attach(entry->handle);
+			seg = dsm_attach(state->handle);
 			if (seg == NULL)
 				elog(ERROR, "could not map dynamic shared memory segment");
 
@@ -198,3 +267,220 @@ GetNamedDSMSegment(const char *name, size_t size,
 
 	return ret;
 }
+
+/*
+ * Initialize or attach a named DSA.
+ *
+ * This routine returns a pointer to the DSA.  A new LWLock tranche ID will be
+ * generated if needed.  Note that the lock tranche will be registered with the
+ * provided name.  Also note that this should be called at most once for a
+ * given DSA in each backend.
+ */
+dsa_area *
+GetNamedDSA(const char *name, bool *found)
+{
+	DSMRegistryEntry *entry;
+	MemoryContext oldcontext;
+	dsa_area   *ret;
+
+	Assert(found);
+
+	if (!name || *name == '\0')
+		ereport(ERROR,
+				(errmsg("DSA name cannot be empty")));
+
+	if (strlen(name) >= offsetof(DSMRegistryEntry, type))
+		ereport(ERROR,
+				(errmsg("DSA name too long")));
+
+	/* Be sure any local memory allocated by DSM/DSA routines is persistent. */
+	oldcontext = MemoryContextSwitchTo(TopMemoryContext);
+
+	/* Connect to the registry. */
+	init_dsm_registry();
+
+	entry = dshash_find_or_insert(dsm_registry_table, name, found);
+	if (!(*found))
+	{
+		NamedDSAState *state = &entry->data.dsa;
+
+		entry->type = DSMR_ENTRY_TYPE_DSA;
+
+		/* Initialize the LWLock tranche for the DSA. */
+		state->tranche = LWLockNewTrancheId();
+		strcpy(state->tranche_name, name);
+		LWLockRegisterTranche(state->tranche, state->tranche_name);
+
+		/* Initialize the DSA. */
+		ret = dsa_create(state->tranche);
+		dsa_pin(ret);
+		dsa_pin_mapping(ret);
+
+		/* Store handle for other backends to use. */
+		state->handle = dsa_get_handle(ret);
+	}
+	else if (entry->type != DSMR_ENTRY_TYPE_DSA)
+		ereport(ERROR,
+				(errmsg("requested DSA does not match type of existing entry")));
+	else
+	{
+		NamedDSAState *state = &entry->data.dsa;
+
+		if (dsa_is_attached(state->handle))
+			ereport(ERROR,
+					(errmsg("requested DSA already attached to current process")));
+
+		/* Initialize existing LWLock tranche for the DSA. */
+		LWLockRegisterTranche(state->tranche, state->tranche_name);
+
+		/* Attach to existing DSA. */
+		ret = dsa_attach(state->handle);
+		dsa_pin_mapping(ret);
+	}
+
+	dshash_release_lock(dsm_registry_table, entry);
+	MemoryContextSwitchTo(oldcontext);
+
+	return ret;
+}
+
+/*
+ * Initialize or attach a named dshash table.
+ *
+ * This routine returns the address of the table.  The tranche_id member of
+ * params is ignored; new tranche IDs will be generated if needed.  Note that
+ * the DSA lock tranche will be registered with the provided name with " DSA"
+ * appended.  The dshash lock tranche will be registered with the provided
+ * name.  Also note that this should be called at most once for a given table
+ * in each backend.
+ */
+dshash_table *
+GetNamedDSHash(const char *name, const dshash_parameters *params, bool *found)
+{
+	DSMRegistryEntry *entry;
+	MemoryContext oldcontext;
+	dshash_table *ret;
+
+	Assert(params);
+	Assert(found);
+
+	if (!name || *name == '\0')
+		ereport(ERROR,
+				(errmsg("DSHash name cannot be empty")));
+
+	if (strlen(name) >= offsetof(DSMRegistryEntry, type))
+		ereport(ERROR,
+				(errmsg("DSHash name too long")));
+
+	/* Be sure any local memory allocated by DSM/DSA routines is persistent. */
+	oldcontext = MemoryContextSwitchTo(TopMemoryContext);
+
+	/* Connect to the registry. */
+	init_dsm_registry();
+
+	entry = dshash_find_or_insert(dsm_registry_table, name, found);
+	if (!(*found))
+	{
+		NamedDSAState *dsa_state = &entry->data.dsh.dsa;
+		NamedDSHState *dsh_state = &entry->data.dsh;
+		dshash_parameters params_copy;
+		dsa_area   *dsa;
+
+		entry->type = DSMR_ENTRY_TYPE_DSH;
+
+		/* Initialize the LWLock tranche for the DSA. */
+		dsa_state->tranche = LWLockNewTrancheId();
+		sprintf(dsa_state->tranche_name, "%s%s", name, DSMR_DSA_TRANCHE_SUFFIX);
+		LWLockRegisterTranche(dsa_state->tranche, dsa_state->tranche_name);
+
+		/* Initialize the LWLock tranche for the dshash table. */
+		dsh_state->tranche = LWLockNewTrancheId();
+		strcpy(dsh_state->tranche_name, name);
+		LWLockRegisterTranche(dsh_state->tranche, dsh_state->tranche_name);
+
+		/* Initialize the DSA for the hash table. */
+		dsa = dsa_create(dsa_state->tranche);
+		dsa_pin(dsa);
+		dsa_pin_mapping(dsa);
+
+		/* Initialize the dshash table. */
+		memcpy(&params_copy, params, sizeof(dshash_parameters));
+		params_copy.tranche_id = dsh_state->tranche;
+		ret = dshash_create(dsa, &params_copy, NULL);
+
+		/* Store handles for other backends to use. */
+		dsa_state->handle = dsa_get_handle(dsa);
+		dsh_state->handle = dshash_get_hash_table_handle(ret);
+	}
+	else if (entry->type != DSMR_ENTRY_TYPE_DSH)
+		ereport(ERROR,
+				(errmsg("requested DSHash does not match type of existing entry")));
+	else
+	{
+		NamedDSAState *dsa_state = &entry->data.dsh.dsa;
+		NamedDSHState *dsh_state = &entry->data.dsh;
+		dsa_area   *dsa;
+
+		/* XXX: Should we verify params matches what table was created with? */
+
+		if (dsa_is_attached(dsa_state->handle))
+			ereport(ERROR,
+					(errmsg("requested DSHash already attached to current process")));
+
+		/* Initialize existing LWLock tranches for the DSA and dshash table. */
+		LWLockRegisterTranche(dsa_state->tranche, dsa_state->tranche_name);
+		LWLockRegisterTranche(dsh_state->tranche, dsh_state->tranche_name);
+
+		/* Attach to existing DSA for the hash table. */
+		dsa = dsa_attach(dsa_state->handle);
+		dsa_pin_mapping(dsa);
+
+		/* Attach to existing dshash table. */
+		ret = dshash_attach(dsa, params, dsh_state->handle, NULL);
+	}
+
+	dshash_release_lock(dsm_registry_table, entry);
+	MemoryContextSwitchTo(oldcontext);
+
+	return ret;
+}
+
+Datum
+pg_get_dsm_registry_allocations(PG_FUNCTION_ARGS)
+{
+	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
+	DSMRegistryEntry *entry;
+	MemoryContext oldcontext;
+	dshash_seq_status status;
+
+	InitMaterializedSRF(fcinfo, MAT_SRF_USE_EXPECTED_DESC);
+
+	/* Be sure any local memory allocated by DSM/DSA routines is persistent. */
+	oldcontext = MemoryContextSwitchTo(TopMemoryContext);
+	init_dsm_registry();
+	MemoryContextSwitchTo(oldcontext);
+
+	dshash_seq_init(&status, dsm_registry_table, false);
+	while ((entry = dshash_seq_next(&status)) != NULL)
+	{
+		Datum		vals[3];
+		bool		nulls[3] = {0};
+
+		vals[0] = CStringGetTextDatum(entry->name);
+		vals[1] = CStringGetTextDatum(DSMREntryTypeNames[entry->type]);
+
+		/*
+		 * Since we can't know the size of DSA/dshash entries without first
+		 * attaching to them, return NULL for those.
+		 */
+		if (entry->type == DSMR_ENTRY_TYPE_DSM)
+			vals[2] = Int64GetDatum(entry->data.dsm.size);
+		else
+			nulls[2] = true;
+
+		tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, vals, nulls);
+	}
+	dshash_seq_term(&status);
+
+	return (Datum) 0;
+}
diff --git a/src/backend/storage/ipc/latch.c b/src/backend/storage/ipc/latch.c
index c6aefd2f688dd..beadeb5e46afa 100644
--- a/src/backend/storage/ipc/latch.c
+++ b/src/backend/storage/ipc/latch.c
@@ -187,9 +187,11 @@ WaitLatch(Latch *latch, int wakeEvents, long timeout,
 	if (!(wakeEvents & WL_LATCH_SET))
 		latch = NULL;
 	ModifyWaitEvent(LatchWaitSet, LatchWaitSetLatchPos, WL_LATCH_SET, latch);
-	ModifyWaitEvent(LatchWaitSet, LatchWaitSetPostmasterDeathPos,
-					(wakeEvents & (WL_EXIT_ON_PM_DEATH | WL_POSTMASTER_DEATH)),
-					NULL);
+
+	if (IsUnderPostmaster)
+		ModifyWaitEvent(LatchWaitSet, LatchWaitSetPostmasterDeathPos,
+						(wakeEvents & (WL_EXIT_ON_PM_DEATH | WL_POSTMASTER_DEATH)),
+						NULL);
 
 	if (WaitEventSetWait(LatchWaitSet,
 						 (wakeEvents & WL_TIMEOUT) ? timeout : -1,
diff --git a/src/backend/storage/ipc/procarray.c b/src/backend/storage/ipc/procarray.c
index e5b945a9ee39c..bf987aed8d327 100644
--- a/src/backend/storage/ipc/procarray.c
+++ b/src/backend/storage/ipc/procarray.c
@@ -1622,58 +1622,6 @@ TransactionIdIsInProgress(TransactionId xid)
 	return false;
 }
 
-/*
- * TransactionIdIsActive -- is xid the top-level XID of an active backend?
- *
- * This differs from TransactionIdIsInProgress in that it ignores prepared
- * transactions, as well as transactions running on the primary if we're in
- * hot standby.  Also, we ignore subtransactions since that's not needed
- * for current uses.
- */
-bool
-TransactionIdIsActive(TransactionId xid)
-{
-	bool		result = false;
-	ProcArrayStruct *arrayP = procArray;
-	TransactionId *other_xids = ProcGlobal->xids;
-	int			i;
-
-	/*
-	 * Don't bother checking a transaction older than RecentXmin; it could not
-	 * possibly still be running.
-	 */
-	if (TransactionIdPrecedes(xid, RecentXmin))
-		return false;
-
-	LWLockAcquire(ProcArrayLock, LW_SHARED);
-
-	for (i = 0; i < arrayP->numProcs; i++)
-	{
-		int			pgprocno = arrayP->pgprocnos[i];
-		PGPROC	   *proc = &allProcs[pgprocno];
-		TransactionId pxid;
-
-		/* Fetch xid just once - see GetNewTransactionId */
-		pxid = UINT32_ACCESS_ONCE(other_xids[i]);
-
-		if (!TransactionIdIsValid(pxid))
-			continue;
-
-		if (proc->pid == 0)
-			continue;			/* ignore prepared transactions */
-
-		if (TransactionIdEquals(pxid, xid))
-		{
-			result = true;
-			break;
-		}
-	}
-
-	LWLockRelease(ProcArrayLock);
-
-	return result;
-}
-
 
 /*
  * Determine XID horizons.
@@ -2866,8 +2814,10 @@ GetRunningTransactionData(void)
  *
  * Similar to GetSnapshotData but returns just oldestActiveXid. We include
  * all PGPROCs with an assigned TransactionId, even VACUUM processes.
- * We look at all databases, though there is no need to include WALSender
- * since this has no effect on hot standby conflicts.
+ *
+ * If allDbs is true, we look at all databases, though there is no need to
+ * include WALSender since this has no effect on hot standby conflicts. If
+ * allDbs is false, skip processes attached to other databases.
  *
  * This is never executed during recovery so there is no need to look at
  * KnownAssignedXids.
@@ -2875,9 +2825,12 @@ GetRunningTransactionData(void)
  * We don't worry about updating other counters, we want to keep this as
  * simple as possible and leave GetSnapshotData() as the primary code for
  * that bookkeeping.
+ *
+ * inCommitOnly indicates getting the oldestActiveXid among the transactions
+ * in the commit critical section.
  */
 TransactionId
-GetOldestActiveTransactionId(void)
+GetOldestActiveTransactionId(bool inCommitOnly, bool allDbs)
 {
 	ProcArrayStruct *arrayP = procArray;
 	TransactionId *other_xids = ProcGlobal->xids;
@@ -2904,6 +2857,8 @@ GetOldestActiveTransactionId(void)
 	for (index = 0; index < arrayP->numProcs; index++)
 	{
 		TransactionId xid;
+		int			pgprocno = arrayP->pgprocnos[index];
+		PGPROC	   *proc = &allProcs[pgprocno];
 
 		/* Fetch xid just once - see GetNewTransactionId */
 		xid = UINT32_ACCESS_ONCE(other_xids[index]);
@@ -2911,6 +2866,13 @@ GetOldestActiveTransactionId(void)
 		if (!TransactionIdIsNormal(xid))
 			continue;
 
+		if (inCommitOnly &&
+			(proc->delayChkptFlags & DELAY_CHKPT_IN_COMMIT) == 0)
+			continue;
+
+		if (!allDbs && proc->databaseId != MyDatabaseId)
+			continue;
+
 		if (TransactionIdPrecedes(xid, oldestRunningXid))
 			oldestRunningXid = xid;
 
diff --git a/src/backend/storage/ipc/procsignal.c b/src/backend/storage/ipc/procsignal.c
index a9bb540b55ac2..087821311cceb 100644
--- a/src/backend/storage/ipc/procsignal.c
+++ b/src/backend/storage/ipc/procsignal.c
@@ -728,7 +728,11 @@ procsignal_sigusr1_handler(SIGNAL_ARGS)
 void
 SendCancelRequest(int backendPID, const uint8 *cancel_key, int cancel_key_len)
 {
-	Assert(backendPID != 0);
+	if (backendPID == 0)
+	{
+		ereport(LOG, (errmsg("invalid cancel request with PID 0")));
+		return;
+	}
 
 	/*
 	 * See if we have a matching backend. Reading the pss_pid and
diff --git a/src/backend/storage/ipc/shmem.c b/src/backend/storage/ipc/shmem.c
index c9ae3b45b76b1..ca3656fc76f43 100644
--- a/src/backend/storage/ipc/shmem.c
+++ b/src/backend/storage/ipc/shmem.c
@@ -679,12 +679,10 @@ pg_get_shmem_allocations_numa(PG_FUNCTION_ARGS)
 		 */
 		for (i = 0; i < shm_ent_page_count; i++)
 		{
-			volatile uint64 touch pg_attribute_unused();
-
 			page_ptrs[i] = startptr + (i * os_page_size);
 
 			if (firstNumaTouch)
-				pg_numa_touch_mem_if_required(touch, page_ptrs[i]);
+				pg_numa_touch_mem_if_required(page_ptrs[i]);
 
 			CHECK_FOR_INTERRUPTS();
 		}
diff --git a/src/backend/storage/ipc/standby.c b/src/backend/storage/ipc/standby.c
index 7fa8d9247e097..4222bdab07807 100644
--- a/src/backend/storage/ipc/standby.c
+++ b/src/backend/storage/ipc/standby.c
@@ -1376,7 +1376,7 @@ LogCurrentRunningXacts(RunningTransactions CurrRunningXacts)
 
 	if (xlrec.subxid_overflow)
 		elog(DEBUG2,
-			 "snapshot of %d running transactions overflowed (lsn %X/%X oldest xid %u latest complete %u next xid %u)",
+			 "snapshot of %d running transactions overflowed (lsn %X/%08X oldest xid %u latest complete %u next xid %u)",
 			 CurrRunningXacts->xcnt,
 			 LSN_FORMAT_ARGS(recptr),
 			 CurrRunningXacts->oldestRunningXid,
@@ -1384,7 +1384,7 @@ LogCurrentRunningXacts(RunningTransactions CurrRunningXacts)
 			 CurrRunningXacts->nextXid);
 	else
 		elog(DEBUG2,
-			 "snapshot of %d+%d running transaction ids (lsn %X/%X oldest xid %u latest complete %u next xid %u)",
+			 "snapshot of %d+%d running transaction ids (lsn %X/%08X oldest xid %u latest complete %u next xid %u)",
 			 CurrRunningXacts->xcnt, CurrRunningXacts->subxcnt,
 			 LSN_FORMAT_ARGS(recptr),
 			 CurrRunningXacts->oldestRunningXid,
diff --git a/src/backend/storage/large_object/inv_api.c b/src/backend/storage/large_object/inv_api.c
index 68b76f2cc18a0..a874000c8ca26 100644
--- a/src/backend/storage/large_object/inv_api.c
+++ b/src/backend/storage/large_object/inv_api.c
@@ -561,7 +561,7 @@ inv_write(LargeObjectDesc *obj_desc, const char *buf, int nbytes)
 		char		data[LOBLKSIZE + VARHDRSZ];
 		/* ensure union is aligned well enough: */
 		int32		align_it;
-	}			workbuf;
+	}			workbuf = {0};
 	char	   *workb = VARDATA(&workbuf.hdr);
 	HeapTuple	newtup;
 	Datum		values[Natts_pg_largeobject];
@@ -752,7 +752,7 @@ inv_truncate(LargeObjectDesc *obj_desc, int64 len)
 		char		data[LOBLKSIZE + VARHDRSZ];
 		/* ensure union is aligned well enough: */
 		int32		align_it;
-	}			workbuf;
+	}			workbuf = {0};
 	char	   *workb = VARDATA(&workbuf.hdr);
 	HeapTuple	newtup;
 	Datum		values[Natts_pg_largeobject];
diff --git a/src/backend/storage/lmgr/generate-lwlocknames.pl b/src/backend/storage/lmgr/generate-lwlocknames.pl
index 4441b7cba0c5f..cd3e43c448aed 100644
--- a/src/backend/storage/lmgr/generate-lwlocknames.pl
+++ b/src/backend/storage/lmgr/generate-lwlocknames.pl
@@ -10,7 +10,6 @@
 my $output_path = '.';
 
 my $lastlockidx = -1;
-my $continue = "\n";
 
 GetOptions('outdir:s' => \$output_path);
 
@@ -28,18 +27,24 @@
 
 
 #
-# First, record the predefined LWLocks listed in wait_event_names.txt.  We'll
-# cross-check those with the ones in lwlocklist.h.
+# First, record the predefined LWLocks and built-in tranches listed in
+# wait_event_names.txt.  We'll cross-check those with the ones in lwlocklist.h.
 #
+my @wait_event_tranches;
 my @wait_event_lwlocks;
 my $record_lwlocks = 0;
+my $in_tranches = 0;
 
 while (<$wait_event_names>)
 {
 	chomp;
 
 	# Check for end marker.
-	last if /^# END OF PREDEFINED LWLOCKS/;
+	if (/^# END OF PREDEFINED LWLOCKS/)
+	{
+		$in_tranches = 1;
+		next;
+	}
 
 	# Skip comments and empty lines.
 	next if /^#/;
@@ -55,13 +60,29 @@
 	# Go to the next line if we are not yet recording LWLocks.
 	next if not $record_lwlocks;
 
+	# Stop recording if we reach another section.
+	last if /^Section:/;
+
 	# Record the LWLock.
 	(my $waiteventname, my $waitevendocsentence) = split(/\t/, $_);
-	push(@wait_event_lwlocks, $waiteventname);
+
+	if ($in_tranches)
+	{
+		push(@wait_event_tranches, $waiteventname);
+	}
+	else
+	{
+		push(@wait_event_lwlocks, $waiteventname);
+	}
 }
 
+#
+# While gathering the list of predefined LWLocks, cross-check the lists in
+# lwlocklist.h with the wait events we just recorded.
+#
 my $in_comment = 0;
-my $i = 0;
+my $lwlock_count = 0;
+my $tranche_count = 0;
 while (<$lwlocklist>)
 {
 	chomp;
@@ -82,40 +103,72 @@
 		next;
 	}
 
-	die "unable to parse lwlocklist.h line \"$_\""
-	  unless /^PG_LWLOCK\((\d+),\s+(\w+)\)$/;
+	#
+	# Gather list of predefined LWLocks and cross-check with the wait events.
+	#
+	if (/^PG_LWLOCK\((\d+),\s+(\w+)\)$/)
+	{
+		my ($lockidx, $lockname) = ($1, $2);
 
-	(my $lockidx, my $lockname) = ($1, $2);
+		die "lwlocklist.h not in order" if $lockidx < $lastlockidx;
+		die "lwlocklist.h has duplicates" if $lockidx == $lastlockidx;
 
-	die "lwlocklist.h not in order" if $lockidx < $lastlockidx;
-	die "lwlocklist.h has duplicates" if $lockidx == $lastlockidx;
+		die "$lockname defined in lwlocklist.h but missing from "
+		  . "wait_event_names.txt"
+		  if $lwlock_count >= scalar @wait_event_lwlocks;
+		die "lists of predefined LWLocks do not match (first mismatch at "
+		  . "$wait_event_lwlocks[$lwlock_count] in wait_event_names.txt and "
+		  . "$lockname in lwlocklist.h)"
+		  if $wait_event_lwlocks[$lwlock_count] ne $lockname;
 
-	die "$lockname defined in lwlocklist.h but missing from "
-	  . "wait_event_names.txt"
-	  if $i >= scalar @wait_event_lwlocks;
-	die "lists of predefined LWLocks do not match (first mismatch at "
-	  . "$wait_event_lwlocks[$i] in wait_event_names.txt and $lockname in "
-	  . "lwlocklist.h)"
-	  if $wait_event_lwlocks[$i] ne $lockname;
-	$i++;
+		$lwlock_count++;
 
-	while ($lastlockidx < $lockidx - 1)
+		while ($lastlockidx < $lockidx - 1)
+		{
+			++$lastlockidx;
+		}
+		$lastlockidx = $lockidx;
+
+		# Add a "Lock" suffix to each lock name, as the C code depends on that.
+		printf $h "#define %-32s (&MainLWLockArray[$lockidx].lock)\n",
+		  $lockname . "Lock";
+
+		next;
+	}
+
+	#
+	# Cross-check the built-in LWLock tranches with the wait events.
+	#
+	if (/^PG_LWLOCKTRANCHE\((\w+),\s+(\w+)\)$/)
 	{
-		++$lastlockidx;
-		$continue = ",\n";
+		my ($tranche_id, $tranche_name) = ($1, $2);
+
+		die "$tranche_name defined in lwlocklist.h but missing from "
+		  . "wait_event_names.txt"
+		  if $tranche_count >= scalar @wait_event_tranches;
+		die
+		  "lists of built-in LWLock tranches do not match (first mismatch at "
+		  . "$wait_event_tranches[$tranche_count] in wait_event_names.txt and "
+		  . "$tranche_name in lwlocklist.h)"
+		  if $wait_event_tranches[$tranche_count] ne $tranche_name;
+
+		$tranche_count++;
+
+		next;
 	}
-	$lastlockidx = $lockidx;
-	$continue = ",\n";
 
-	# Add a "Lock" suffix to each lock name, as the C code depends on that
-	printf $h "#define %-32s (&MainLWLockArray[$lockidx].lock)\n",
-	  $lockname . "Lock";
+	die "unable to parse lwlocklist.h line \"$_\"";
 }
 
 die
-  "$wait_event_lwlocks[$i] defined in wait_event_names.txt but missing from "
-  . "lwlocklist.h"
-  if $i < scalar @wait_event_lwlocks;
+  "$wait_event_lwlocks[$lwlock_count] defined in wait_event_names.txt but "
+  . " missing from lwlocklist.h"
+  if $lwlock_count < scalar @wait_event_lwlocks;
+
+die
+  "$wait_event_tranches[$tranche_count] defined in wait_event_names.txt but "
+  . "missing from lwlocklist.h"
+  if $tranche_count < scalar @wait_event_tranches;
 
 print $h "\n";
 printf $h "#define NUM_INDIVIDUAL_LWLOCKS		%s\n", $lastlockidx + 1;
diff --git a/src/backend/storage/lmgr/lock.c b/src/backend/storage/lmgr/lock.c
index 2776ceb295be4..62f3471448ebc 100644
--- a/src/backend/storage/lmgr/lock.c
+++ b/src/backend/storage/lmgr/lock.c
@@ -3539,9 +3539,9 @@ AtPrepare_Locks(void)
  * but that probably costs more cycles.
  */
 void
-PostPrepare_Locks(TransactionId xid)
+PostPrepare_Locks(FullTransactionId fxid)
 {
-	PGPROC	   *newproc = TwoPhaseGetDummyProc(xid, false);
+	PGPROC	   *newproc = TwoPhaseGetDummyProc(fxid, false);
 	HASH_SEQ_STATUS status;
 	LOCALLOCK  *locallock;
 	LOCK	   *lock;
@@ -4324,11 +4324,11 @@ DumpAllLocks(void)
  * and PANIC anyway.
  */
 void
-lock_twophase_recover(TransactionId xid, uint16 info,
+lock_twophase_recover(FullTransactionId fxid, uint16 info,
 					  void *recdata, uint32 len)
 {
 	TwoPhaseLockRecord *rec = (TwoPhaseLockRecord *) recdata;
-	PGPROC	   *proc = TwoPhaseGetDummyProc(xid, false);
+	PGPROC	   *proc = TwoPhaseGetDummyProc(fxid, false);
 	LOCKTAG    *locktag;
 	LOCKMODE	lockmode;
 	LOCKMETHODID lockmethodid;
@@ -4505,7 +4505,7 @@ lock_twophase_recover(TransactionId xid, uint16 info,
  * starting up into hot standby mode.
  */
 void
-lock_twophase_standby_recover(TransactionId xid, uint16 info,
+lock_twophase_standby_recover(FullTransactionId fxid, uint16 info,
 							  void *recdata, uint32 len)
 {
 	TwoPhaseLockRecord *rec = (TwoPhaseLockRecord *) recdata;
@@ -4524,7 +4524,7 @@ lock_twophase_standby_recover(TransactionId xid, uint16 info,
 	if (lockmode == AccessExclusiveLock &&
 		locktag->locktag_type == LOCKTAG_RELATION)
 	{
-		StandbyAcquireAccessExclusiveLock(xid,
+		StandbyAcquireAccessExclusiveLock(XidFromFullTransactionId(fxid),
 										  locktag->locktag_field1 /* dboid */ ,
 										  locktag->locktag_field2 /* reloid */ );
 	}
@@ -4537,11 +4537,11 @@ lock_twophase_standby_recover(TransactionId xid, uint16 info,
  * Find and release the lock indicated by the 2PC record.
  */
 void
-lock_twophase_postcommit(TransactionId xid, uint16 info,
+lock_twophase_postcommit(FullTransactionId fxid, uint16 info,
 						 void *recdata, uint32 len)
 {
 	TwoPhaseLockRecord *rec = (TwoPhaseLockRecord *) recdata;
-	PGPROC	   *proc = TwoPhaseGetDummyProc(xid, true);
+	PGPROC	   *proc = TwoPhaseGetDummyProc(fxid, true);
 	LOCKTAG    *locktag;
 	LOCKMETHODID lockmethodid;
 	LockMethod	lockMethodTable;
@@ -4563,10 +4563,10 @@ lock_twophase_postcommit(TransactionId xid, uint16 info,
  * This is actually just the same as the COMMIT case.
  */
 void
-lock_twophase_postabort(TransactionId xid, uint16 info,
+lock_twophase_postabort(FullTransactionId fxid, uint16 info,
 						void *recdata, uint32 len)
 {
-	lock_twophase_postcommit(xid, info, recdata, len);
+	lock_twophase_postcommit(fxid, info, recdata, len);
 }
 
 /*
diff --git a/src/backend/storage/lmgr/lwlock.c b/src/backend/storage/lmgr/lwlock.c
index 46f44bc45113f..ec9c345ffdfb8 100644
--- a/src/backend/storage/lmgr/lwlock.c
+++ b/src/backend/storage/lmgr/lwlock.c
@@ -122,9 +122,8 @@ StaticAssertDecl((LW_VAL_EXCLUSIVE & LW_FLAG_MASK) == 0,
  * own tranche.  We absorb the names of these tranches from there into
  * BuiltinTrancheNames here.
  *
- * 2. There are some predefined tranches for built-in groups of locks.
- * These are listed in enum BuiltinTrancheIds in lwlock.h, and their names
- * appear in BuiltinTrancheNames[] below.
+ * 2. There are some predefined tranches for built-in groups of locks defined
+ * in lwlocklist.h.  We absorb the names of these tranches, too.
  *
  * 3. Extensions can create new tranches, via either RequestNamedLWLockTranche
  * or LWLockRegisterTranche.  The names of these that are known in the current
@@ -135,49 +134,10 @@ StaticAssertDecl((LW_VAL_EXCLUSIVE & LW_FLAG_MASK) == 0,
  */
 static const char *const BuiltinTrancheNames[] = {
 #define PG_LWLOCK(id, lockname) [id] = CppAsString(lockname),
+#define PG_LWLOCKTRANCHE(id, lockname) [LWTRANCHE_##id] = CppAsString(lockname),
 #include "storage/lwlocklist.h"
 #undef PG_LWLOCK
-	[LWTRANCHE_XACT_BUFFER] = "XactBuffer",
-	[LWTRANCHE_COMMITTS_BUFFER] = "CommitTsBuffer",
-	[LWTRANCHE_SUBTRANS_BUFFER] = "SubtransBuffer",
-	[LWTRANCHE_MULTIXACTOFFSET_BUFFER] = "MultiXactOffsetBuffer",
-	[LWTRANCHE_MULTIXACTMEMBER_BUFFER] = "MultiXactMemberBuffer",
-	[LWTRANCHE_NOTIFY_BUFFER] = "NotifyBuffer",
-	[LWTRANCHE_SERIAL_BUFFER] = "SerialBuffer",
-	[LWTRANCHE_WAL_INSERT] = "WALInsert",
-	[LWTRANCHE_BUFFER_CONTENT] = "BufferContent",
-	[LWTRANCHE_REPLICATION_ORIGIN_STATE] = "ReplicationOriginState",
-	[LWTRANCHE_REPLICATION_SLOT_IO] = "ReplicationSlotIO",
-	[LWTRANCHE_LOCK_FASTPATH] = "LockFastPath",
-	[LWTRANCHE_BUFFER_MAPPING] = "BufferMapping",
-	[LWTRANCHE_LOCK_MANAGER] = "LockManager",
-	[LWTRANCHE_PREDICATE_LOCK_MANAGER] = "PredicateLockManager",
-	[LWTRANCHE_PARALLEL_HASH_JOIN] = "ParallelHashJoin",
-	[LWTRANCHE_PARALLEL_BTREE_SCAN] = "ParallelBtreeScan",
-	[LWTRANCHE_PARALLEL_QUERY_DSA] = "ParallelQueryDSA",
-	[LWTRANCHE_PER_SESSION_DSA] = "PerSessionDSA",
-	[LWTRANCHE_PER_SESSION_RECORD_TYPE] = "PerSessionRecordType",
-	[LWTRANCHE_PER_SESSION_RECORD_TYPMOD] = "PerSessionRecordTypmod",
-	[LWTRANCHE_SHARED_TUPLESTORE] = "SharedTupleStore",
-	[LWTRANCHE_SHARED_TIDBITMAP] = "SharedTidBitmap",
-	[LWTRANCHE_PARALLEL_APPEND] = "ParallelAppend",
-	[LWTRANCHE_PER_XACT_PREDICATE_LIST] = "PerXactPredicateList",
-	[LWTRANCHE_PGSTATS_DSA] = "PgStatsDSA",
-	[LWTRANCHE_PGSTATS_HASH] = "PgStatsHash",
-	[LWTRANCHE_PGSTATS_DATA] = "PgStatsData",
-	[LWTRANCHE_LAUNCHER_DSA] = "LogicalRepLauncherDSA",
-	[LWTRANCHE_LAUNCHER_HASH] = "LogicalRepLauncherHash",
-	[LWTRANCHE_DSM_REGISTRY_DSA] = "DSMRegistryDSA",
-	[LWTRANCHE_DSM_REGISTRY_HASH] = "DSMRegistryHash",
-	[LWTRANCHE_COMMITTS_SLRU] = "CommitTsSLRU",
-	[LWTRANCHE_MULTIXACTOFFSET_SLRU] = "MultixactOffsetSLRU",
-	[LWTRANCHE_MULTIXACTMEMBER_SLRU] = "MultixactMemberSLRU",
-	[LWTRANCHE_NOTIFY_SLRU] = "NotifySLRU",
-	[LWTRANCHE_SERIAL_SLRU] = "SerialSLRU",
-	[LWTRANCHE_SUBTRANS_SLRU] = "SubtransSLRU",
-	[LWTRANCHE_XACT_SLRU] = "XactSLRU",
-	[LWTRANCHE_PARALLEL_VACUUM_DSA] = "ParallelVacuumDSA",
-	[LWTRANCHE_AIO_URING_COMPLETION] = "AioUringCompletion",
+#undef PG_LWLOCKTRANCHE
 };
 
 StaticAssertDecl(lengthof(BuiltinTrancheNames) ==
diff --git a/src/backend/storage/lmgr/predicate.c b/src/backend/storage/lmgr/predicate.c
index d82114ffca165..c07fb58835557 100644
--- a/src/backend/storage/lmgr/predicate.c
+++ b/src/backend/storage/lmgr/predicate.c
@@ -191,7 +191,7 @@
  *		AtPrepare_PredicateLocks(void);
  *		PostPrepare_PredicateLocks(TransactionId xid);
  *		PredicateLockTwoPhaseFinish(TransactionId xid, bool isCommit);
- *		predicatelock_twophase_recover(TransactionId xid, uint16 info,
+ *		predicatelock_twophase_recover(FullTransactionId fxid, uint16 info,
  *									   void *recdata, uint32 len);
  */
 
@@ -4856,7 +4856,7 @@ AtPrepare_PredicateLocks(void)
  *		anyway. We only need to clean up our local state.
  */
 void
-PostPrepare_PredicateLocks(TransactionId xid)
+PostPrepare_PredicateLocks(FullTransactionId fxid)
 {
 	if (MySerializableXact == InvalidSerializableXact)
 		return;
@@ -4879,12 +4879,12 @@ PostPrepare_PredicateLocks(TransactionId xid)
  *		commits or aborts.
  */
 void
-PredicateLockTwoPhaseFinish(TransactionId xid, bool isCommit)
+PredicateLockTwoPhaseFinish(FullTransactionId fxid, bool isCommit)
 {
 	SERIALIZABLEXID *sxid;
 	SERIALIZABLEXIDTAG sxidtag;
 
-	sxidtag.xid = xid;
+	sxidtag.xid = XidFromFullTransactionId(fxid);
 
 	LWLockAcquire(SerializableXactHashLock, LW_SHARED);
 	sxid = (SERIALIZABLEXID *)
@@ -4906,10 +4906,11 @@ PredicateLockTwoPhaseFinish(TransactionId xid, bool isCommit)
  * Re-acquire a predicate lock belonging to a transaction that was prepared.
  */
 void
-predicatelock_twophase_recover(TransactionId xid, uint16 info,
+predicatelock_twophase_recover(FullTransactionId fxid, uint16 info,
 							   void *recdata, uint32 len)
 {
 	TwoPhasePredicateRecord *record;
+	TransactionId xid = XidFromFullTransactionId(fxid);
 
 	Assert(len == sizeof(TwoPhasePredicateRecord));
 
diff --git a/src/backend/tcop/backend_startup.c b/src/backend/tcop/backend_startup.c
index ad0af5edc1f21..14d5fc0b1965a 100644
--- a/src/backend/tcop/backend_startup.c
+++ b/src/backend/tcop/backend_startup.c
@@ -492,7 +492,7 @@ static int
 ProcessStartupPacket(Port *port, bool ssl_done, bool gss_done)
 {
 	int32		len;
-	char	   *buf;
+	char	   *buf = NULL;
 	ProtocolVersion proto;
 	MemoryContext oldcontext;
 
@@ -516,7 +516,7 @@ ProcessStartupPacket(Port *port, bool ssl_done, bool gss_done)
 		 * scanners, which may be less benign, but it's not really our job to
 		 * notice those.)
 		 */
-		return STATUS_ERROR;
+		goto fail;
 	}
 
 	if (pq_getbytes(((char *) &len) + 1, 3) == EOF)
@@ -526,7 +526,7 @@ ProcessStartupPacket(Port *port, bool ssl_done, bool gss_done)
 			ereport(COMMERROR,
 					(errcode(ERRCODE_PROTOCOL_VIOLATION),
 					 errmsg("incomplete startup packet")));
-		return STATUS_ERROR;
+		goto fail;
 	}
 
 	len = pg_ntoh32(len);
@@ -538,7 +538,7 @@ ProcessStartupPacket(Port *port, bool ssl_done, bool gss_done)
 		ereport(COMMERROR,
 				(errcode(ERRCODE_PROTOCOL_VIOLATION),
 				 errmsg("invalid length of startup packet")));
-		return STATUS_ERROR;
+		goto fail;
 	}
 
 	/*
@@ -554,7 +554,7 @@ ProcessStartupPacket(Port *port, bool ssl_done, bool gss_done)
 		ereport(COMMERROR,
 				(errcode(ERRCODE_PROTOCOL_VIOLATION),
 				 errmsg("incomplete startup packet")));
-		return STATUS_ERROR;
+		goto fail;
 	}
 	pq_endmsgread();
 
@@ -568,7 +568,7 @@ ProcessStartupPacket(Port *port, bool ssl_done, bool gss_done)
 	{
 		ProcessCancelRequestPacket(port, buf, len);
 		/* Not really an error, but we don't want to proceed further */
-		return STATUS_ERROR;
+		goto fail;
 	}
 
 	if (proto == NEGOTIATE_SSL_CODE && !ssl_done)
@@ -607,14 +607,16 @@ ProcessStartupPacket(Port *port, bool ssl_done, bool gss_done)
 			ereport(COMMERROR,
 					(errcode_for_socket_access(),
 					 errmsg("failed to send SSL negotiation response: %m")));
-			return STATUS_ERROR;	/* close the connection */
+			goto fail;			/* close the connection */
 		}
 
 #ifdef USE_SSL
 		if (SSLok == 'S' && secure_open_server(port) == -1)
-			return STATUS_ERROR;
+			goto fail;
 #endif
 
+		pfree(buf);
+
 		/*
 		 * At this point we should have no data already buffered.  If we do,
 		 * it was received before we performed the SSL handshake, so it wasn't
@@ -661,14 +663,16 @@ ProcessStartupPacket(Port *port, bool ssl_done, bool gss_done)
 			ereport(COMMERROR,
 					(errcode_for_socket_access(),
 					 errmsg("failed to send GSSAPI negotiation response: %m")));
-			return STATUS_ERROR;	/* close the connection */
+			goto fail;			/* close the connection */
 		}
 
 #ifdef ENABLE_GSS
 		if (GSSok == 'G' && secure_open_gssapi(port) == -1)
-			return STATUS_ERROR;
+			goto fail;
 #endif
 
+		pfree(buf);
+
 		/*
 		 * At this point we should have no data already buffered.  If we do,
 		 * it was received before we performed the GSS handshake, so it wasn't
@@ -863,7 +867,16 @@ ProcessStartupPacket(Port *port, bool ssl_done, bool gss_done)
 	 */
 	MemoryContextSwitchTo(oldcontext);
 
+	pfree(buf);
+
 	return STATUS_OK;
+
+fail:
+	/* be tidy, just to avoid Valgrind complaints */
+	if (buf)
+		pfree(buf);
+
+	return STATUS_ERROR;
 }
 
 /*
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 2f8c3d5f91822..0cecd4649020f 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -988,6 +988,7 @@ pg_plan_queries(List *querytrees, const char *query_string, int cursorOptions,
 			stmt->stmt_location = query->stmt_location;
 			stmt->stmt_len = query->stmt_len;
 			stmt->queryId = query->queryId;
+			stmt->planOrigin = PLAN_STMT_INTERNAL;
 		}
 		else
 		{
diff --git a/src/backend/tcop/pquery.c b/src/backend/tcop/pquery.c
index d1593f38b35fd..08791b8f75ec2 100644
--- a/src/backend/tcop/pquery.c
+++ b/src/backend/tcop/pquery.c
@@ -1350,24 +1350,15 @@ PortalRunMulti(Portal portal,
 		PopActiveSnapshot();
 
 	/*
-	 * If a query completion data was supplied, use it.  Otherwise use the
-	 * portal's query completion data.
-	 *
-	 * Exception: Clients expect INSERT/UPDATE/DELETE tags to have counts, so
-	 * fake them with zeros.  This can happen with DO INSTEAD rules if there
-	 * is no replacement query of the same type as the original.  We print "0
-	 * 0" here because technically there is no query of the matching tag type,
-	 * and printing a non-zero count for a different query type seems wrong,
-	 * e.g.  an INSERT that does an UPDATE instead should not print "0 1" if
-	 * one row was updated.  See QueryRewrite(), step 3, for details.
+	 * If a command tag was requested and we did not fill in a run-time-
+	 * determined tag above, copy the parse-time tag from the Portal.  (There
+	 * might not be any tag there either, in edge cases such as empty prepared
+	 * statements.  That's OK.)
 	 */
-	if (qc && qc->commandTag == CMDTAG_UNKNOWN)
-	{
-		if (portal->qc.commandTag != CMDTAG_UNKNOWN)
-			CopyQueryCompletion(qc, &portal->qc);
-		/* If the caller supplied a qc, we should have set it by now. */
-		Assert(qc->commandTag != CMDTAG_UNKNOWN);
-	}
+	if (qc &&
+		qc->commandTag == CMDTAG_UNKNOWN &&
+		portal->qc.commandTag != CMDTAG_UNKNOWN)
+		CopyQueryCompletion(qc, &portal->qc);
 }
 
 /*
diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index 25fe3d5801665..4f4191b0ea6b4 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -943,17 +943,7 @@ standard_ProcessUtility(PlannedStmt *pstmt,
 			break;
 
 		case T_CheckPointStmt:
-			if (!has_privs_of_role(GetUserId(), ROLE_PG_CHECKPOINT))
-				ereport(ERROR,
-						(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
-				/* translator: %s is name of a SQL command, eg CHECKPOINT */
-						 errmsg("permission denied to execute %s command",
-								"CHECKPOINT"),
-						 errdetail("Only roles with privileges of the \"%s\" role may execute this command.",
-								   "pg_checkpoint")));
-
-			RequestCheckpoint(CHECKPOINT_IMMEDIATE | CHECKPOINT_WAIT |
-							  (RecoveryInProgress() ? 0 : CHECKPOINT_FORCE));
+			ExecCheckpoint(pstate, (CheckPointStmt *) parsetree);
 			break;
 
 			/*
@@ -1244,6 +1234,7 @@ ProcessUtilitySlow(ParseState *pstate,
 							wrapper->utilityStmt = stmt;
 							wrapper->stmt_location = pstmt->stmt_location;
 							wrapper->stmt_len = pstmt->stmt_len;
+							wrapper->planOrigin = PLAN_STMT_INTERNAL;
 
 							ProcessUtility(wrapper,
 										   queryString,
@@ -1343,7 +1334,7 @@ ProcessUtilitySlow(ParseState *pstate,
 					 */
 					switch (stmt->subtype)
 					{
-						case 'T':	/* ALTER DOMAIN DEFAULT */
+						case AD_AlterDefault:
 
 							/*
 							 * Recursively alter column default for table and,
@@ -1353,30 +1344,30 @@ ProcessUtilitySlow(ParseState *pstate,
 								AlterDomainDefault(stmt->typeName,
 												   stmt->def);
 							break;
-						case 'N':	/* ALTER DOMAIN DROP NOT NULL */
+						case AD_DropNotNull:
 							address =
 								AlterDomainNotNull(stmt->typeName,
 												   false);
 							break;
-						case 'O':	/* ALTER DOMAIN SET NOT NULL */
+						case AD_SetNotNull:
 							address =
 								AlterDomainNotNull(stmt->typeName,
 												   true);
 							break;
-						case 'C':	/* ADD CONSTRAINT */
+						case AD_AddConstraint:
 							address =
 								AlterDomainAddConstraint(stmt->typeName,
 														 stmt->def,
 														 &secondaryObject);
 							break;
-						case 'X':	/* DROP CONSTRAINT */
+						case AD_DropConstraint:
 							address =
 								AlterDomainDropConstraint(stmt->typeName,
 														  stmt->name,
 														  stmt->behavior,
 														  stmt->missing_ok);
 							break;
-						case 'V':	/* VALIDATE CONSTRAINT */
+						case AD_ValidateConstraint:
 							address =
 								AlterDomainValidateConstraint(stmt->typeName,
 															  stmt->name);
@@ -1974,6 +1965,7 @@ ProcessUtilityForAlterTable(Node *stmt, AlterTableUtilityContext *context)
 	wrapper->utilityStmt = stmt;
 	wrapper->stmt_location = context->pstmt->stmt_location;
 	wrapper->stmt_len = context->pstmt->stmt_len;
+	wrapper->planOrigin = PLAN_STMT_INTERNAL;
 
 	ProcessUtility(wrapper,
 				   context->queryString,
diff --git a/src/backend/tsearch/dict_ispell.c b/src/backend/tsearch/dict_ispell.c
index 63bd193a78a89..debfbf956cc1f 100644
--- a/src/backend/tsearch/dict_ispell.c
+++ b/src/backend/tsearch/dict_ispell.c
@@ -47,24 +47,30 @@ dispell_init(PG_FUNCTION_ARGS)
 
 		if (strcmp(defel->defname, "dictfile") == 0)
 		{
+			char	   *filename;
+
 			if (dictloaded)
 				ereport(ERROR,
 						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 						 errmsg("multiple DictFile parameters")));
-			NIImportDictionary(&(d->obj),
-							   get_tsearch_config_filename(defGetString(defel),
-														   "dict"));
+			filename = get_tsearch_config_filename(defGetString(defel),
+												   "dict");
+			NIImportDictionary(&(d->obj), filename);
+			pfree(filename);
 			dictloaded = true;
 		}
 		else if (strcmp(defel->defname, "afffile") == 0)
 		{
+			char	   *filename;
+
 			if (affloaded)
 				ereport(ERROR,
 						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 						 errmsg("multiple AffFile parameters")));
-			NIImportAffixes(&(d->obj),
-							get_tsearch_config_filename(defGetString(defel),
-														"affix"));
+			filename = get_tsearch_config_filename(defGetString(defel),
+												   "affix");
+			NIImportAffixes(&(d->obj), filename);
+			pfree(filename);
 			affloaded = true;
 		}
 		else if (strcmp(defel->defname, "stopwords") == 0)
diff --git a/src/backend/tsearch/dict_synonym.c b/src/backend/tsearch/dict_synonym.c
index 0da5a9d686802..c2773eb01adee 100644
--- a/src/backend/tsearch/dict_synonym.c
+++ b/src/backend/tsearch/dict_synonym.c
@@ -199,6 +199,7 @@ dsynonym_init(PG_FUNCTION_ARGS)
 	}
 
 	tsearch_readline_end(&trst);
+	pfree(filename);
 
 	d->len = cur;
 	qsort(d->syn, d->len, sizeof(Syn), compareSyn);
diff --git a/src/backend/tsearch/dict_thesaurus.c b/src/backend/tsearch/dict_thesaurus.c
index 1bebe36a6910e..1e6bbde1ca7d8 100644
--- a/src/backend/tsearch/dict_thesaurus.c
+++ b/src/backend/tsearch/dict_thesaurus.c
@@ -167,17 +167,17 @@ addWrd(DictThesaurus *d, char *b, char *e, uint32 idsubst, uint16 nwrd, uint16 p
 static void
 thesaurusRead(const char *filename, DictThesaurus *d)
 {
+	char	   *real_filename = get_tsearch_config_filename(filename, "ths");
 	tsearch_readline_state trst;
 	uint32		idsubst = 0;
 	bool		useasis = false;
 	char	   *line;
 
-	filename = get_tsearch_config_filename(filename, "ths");
-	if (!tsearch_readline_begin(&trst, filename))
+	if (!tsearch_readline_begin(&trst, real_filename))
 		ereport(ERROR,
 				(errcode(ERRCODE_CONFIG_FILE_ERROR),
 				 errmsg("could not open thesaurus file \"%s\": %m",
-						filename)));
+						real_filename)));
 
 	while ((line = tsearch_readline(&trst)) != NULL)
 	{
@@ -297,6 +297,7 @@ thesaurusRead(const char *filename, DictThesaurus *d)
 	d->nsubst = idsubst;
 
 	tsearch_readline_end(&trst);
+	pfree(real_filename);
 }
 
 static TheLexeme *
diff --git a/src/backend/tsearch/ts_locale.c b/src/backend/tsearch/ts_locale.c
index b77d8c23d3694..4801fe90089e6 100644
--- a/src/backend/tsearch/ts_locale.c
+++ b/src/backend/tsearch/ts_locale.c
@@ -36,7 +36,7 @@ t_isalpha(const char *ptr)
 {
 	int			clen = pg_mblen(ptr);
 	wchar_t		character[WC_BUF_LEN];
-	pg_locale_t mylocale = 0;	/* TODO */
+	locale_t	mylocale = 0;	/* TODO */
 
 	if (clen == 1 || database_ctype_is_c)
 		return isalpha(TOUCHAR(ptr));
@@ -51,7 +51,7 @@ t_isalnum(const char *ptr)
 {
 	int			clen = pg_mblen(ptr);
 	wchar_t		character[WC_BUF_LEN];
-	pg_locale_t mylocale = 0;	/* TODO */
+	locale_t	mylocale = 0;	/* TODO */
 
 	if (clen == 1 || database_ctype_is_c)
 		return isalnum(TOUCHAR(ptr));
diff --git a/src/backend/tsearch/ts_selfuncs.c b/src/backend/tsearch/ts_selfuncs.c
index 0c1d2bc1109da..453a5e5c2ea06 100644
--- a/src/backend/tsearch/ts_selfuncs.c
+++ b/src/backend/tsearch/ts_selfuncs.c
@@ -233,7 +233,7 @@ mcelem_tsquery_selec(TSQuery query, Datum *mcelem, int nmcelem,
 		 * The text Datums came from an array, so it cannot be compressed or
 		 * stored out-of-line -- it's safe to use VARSIZE_ANY*.
 		 */
-		Assert(!VARATT_IS_COMPRESSED(mcelem[i]) && !VARATT_IS_EXTERNAL(mcelem[i]));
+		Assert(!VARATT_IS_COMPRESSED(DatumGetPointer(mcelem[i])) && !VARATT_IS_EXTERNAL(DatumGetPointer(mcelem[i])));
 		lookup[i].element = (text *) DatumGetPointer(mcelem[i]);
 		lookup[i].frequency = numbers[i];
 	}
diff --git a/src/backend/tsearch/wparser_def.c b/src/backend/tsearch/wparser_def.c
index 79bcd32a0639e..e2dd3da3aa35f 100644
--- a/src/backend/tsearch/wparser_def.c
+++ b/src/backend/tsearch/wparser_def.c
@@ -299,7 +299,7 @@ TParserInit(char *str, int len)
 	 */
 	if (prs->charmaxlen > 1)
 	{
-		pg_locale_t mylocale = 0;	/* TODO */
+		locale_t	mylocale = 0;	/* TODO */
 
 		prs->usewide = true;
 		if (database_ctype_is_c)
diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c
index 8b57845e8709f..6bc91ce0dadda 100644
--- a/src/backend/utils/activity/pgstat.c
+++ b/src/backend/utils/activity/pgstat.c
@@ -212,6 +212,11 @@ int			pgstat_fetch_consistency = PGSTAT_FETCH_CONSISTENCY_CACHE;
 
 PgStat_LocalState pgStatLocal;
 
+/*
+ * Track pending reports for fixed-numbered stats, used by
+ * pgstat_report_stat().
+ */
+bool		pgstat_report_fixed = false;
 
 /* ----------
  * Local data
@@ -370,7 +375,6 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
 		.shared_data_off = offsetof(PgStatShared_Backend, stats),
 		.shared_data_len = sizeof(((PgStatShared_Backend *) 0)->stats),
 
-		.have_static_pending_cb = pgstat_backend_have_pending_cb,
 		.flush_static_cb = pgstat_backend_flush_cb,
 		.reset_timestamp_cb = pgstat_backend_reset_timestamp_cb,
 	},
@@ -437,7 +441,6 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
 		.shared_data_len = sizeof(((PgStatShared_IO *) 0)->stats),
 
 		.flush_static_cb = pgstat_io_flush_cb,
-		.have_static_pending_cb = pgstat_io_have_pending_cb,
 		.init_shmem_cb = pgstat_io_init_shmem_cb,
 		.reset_all_cb = pgstat_io_reset_all_cb,
 		.snapshot_cb = pgstat_io_snapshot_cb,
@@ -455,7 +458,6 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
 		.shared_data_len = sizeof(((PgStatShared_SLRU *) 0)->stats),
 
 		.flush_static_cb = pgstat_slru_flush_cb,
-		.have_static_pending_cb = pgstat_slru_have_pending_cb,
 		.init_shmem_cb = pgstat_slru_init_shmem_cb,
 		.reset_all_cb = pgstat_slru_reset_all_cb,
 		.snapshot_cb = pgstat_slru_snapshot_cb,
@@ -474,7 +476,6 @@ static const PgStat_KindInfo pgstat_kind_builtin_infos[PGSTAT_KIND_BUILTIN_SIZE]
 
 		.init_backend_cb = pgstat_wal_init_backend_cb,
 		.flush_static_cb = pgstat_wal_flush_cb,
-		.have_static_pending_cb = pgstat_wal_have_pending_cb,
 		.init_shmem_cb = pgstat_wal_init_shmem_cb,
 		.reset_all_cb = pgstat_wal_reset_all_cb,
 		.snapshot_cb = pgstat_wal_snapshot_cb,
@@ -708,29 +709,10 @@ pgstat_report_stat(bool force)
 	}
 
 	/* Don't expend a clock check if nothing to do */
-	if (dlist_is_empty(&pgStatPending))
+	if (dlist_is_empty(&pgStatPending) &&
+		!pgstat_report_fixed)
 	{
-		bool		do_flush = false;
-
-		/* Check for pending stats */
-		for (PgStat_Kind kind = PGSTAT_KIND_MIN; kind <= PGSTAT_KIND_MAX; kind++)
-		{
-			const PgStat_KindInfo *kind_info = pgstat_get_kind_info(kind);
-
-			if (!kind_info)
-				continue;
-			if (!kind_info->have_static_pending_cb)
-				continue;
-
-			if (kind_info->have_static_pending_cb())
-			{
-				do_flush = true;
-				break;
-			}
-		}
-
-		if (!do_flush)
-			return 0;
+		return 0;
 	}
 
 	/*
@@ -784,16 +766,19 @@ pgstat_report_stat(bool force)
 	partial_flush |= pgstat_flush_pending_entries(nowait);
 
 	/* flush of other stats kinds */
-	for (PgStat_Kind kind = PGSTAT_KIND_MIN; kind <= PGSTAT_KIND_MAX; kind++)
+	if (pgstat_report_fixed)
 	{
-		const PgStat_KindInfo *kind_info = pgstat_get_kind_info(kind);
+		for (PgStat_Kind kind = PGSTAT_KIND_MIN; kind <= PGSTAT_KIND_MAX; kind++)
+		{
+			const PgStat_KindInfo *kind_info = pgstat_get_kind_info(kind);
 
-		if (!kind_info)
-			continue;
-		if (!kind_info->flush_static_cb)
-			continue;
+			if (!kind_info)
+				continue;
+			if (!kind_info->flush_static_cb)
+				continue;
 
-		partial_flush |= kind_info->flush_static_cb(nowait);
+			partial_flush |= kind_info->flush_static_cb(nowait);
+		}
 	}
 
 	last_flush = now;
@@ -815,6 +800,7 @@ pgstat_report_stat(bool force)
 	}
 
 	pending_since = 0;
+	pgstat_report_fixed = false;
 
 	return 0;
 }
diff --git a/src/backend/utils/activity/pgstat_backend.c b/src/backend/utils/activity/pgstat_backend.c
index 51256277e8d37..8714a85e2d936 100644
--- a/src/backend/utils/activity/pgstat_backend.c
+++ b/src/backend/utils/activity/pgstat_backend.c
@@ -66,6 +66,7 @@ pgstat_count_backend_io_op_time(IOObject io_object, IOContext io_context,
 				   io_time);
 
 	backend_has_iostats = true;
+	pgstat_report_fixed = true;
 }
 
 void
@@ -81,6 +82,7 @@ pgstat_count_backend_io_op(IOObject io_object, IOContext io_context,
 	PendingBackendStats.pending_io.bytes[io_object][io_context][io_op] += bytes;
 
 	backend_has_iostats = true;
+	pgstat_report_fixed = true;
 }
 
 /*
@@ -301,18 +303,6 @@ pgstat_flush_backend(bool nowait, bits32 flags)
 	return false;
 }
 
-/*
- * Check if there are any backend stats waiting for flush.
- */
-bool
-pgstat_backend_have_pending_cb(void)
-{
-	if (!pgstat_tracks_backend_bktype(MyBackendType))
-		return false;
-
-	return (backend_has_iostats || pgstat_backend_wal_have_pending());
-}
-
 /*
  * Callback to flush out locally pending backend statistics.
  *
diff --git a/src/backend/utils/activity/pgstat_io.c b/src/backend/utils/activity/pgstat_io.c
index d8d26379a571e..13ae57ed6498d 100644
--- a/src/backend/utils/activity/pgstat_io.c
+++ b/src/backend/utils/activity/pgstat_io.c
@@ -80,6 +80,7 @@ pgstat_count_io_op(IOObject io_object, IOContext io_context, IOOp io_op,
 	pgstat_count_backend_io_op(io_object, io_context, io_op, cnt, bytes);
 
 	have_iostats = true;
+	pgstat_report_fixed = true;
 }
 
 /*
@@ -167,15 +168,6 @@ pgstat_fetch_stat_io(void)
 	return &pgStatLocal.snapshot.io;
 }
 
-/*
- * Check if there any IO stats waiting for flush.
- */
-bool
-pgstat_io_have_pending_cb(void)
-{
-	return have_iostats;
-}
-
 /*
  * Simpler wrapper of pgstat_io_flush_cb()
  */
diff --git a/src/backend/utils/activity/pgstat_relation.c b/src/backend/utils/activity/pgstat_relation.c
index 28587e2916b1d..69df741cbf630 100644
--- a/src/backend/utils/activity/pgstat_relation.c
+++ b/src/backend/utils/activity/pgstat_relation.c
@@ -744,7 +744,7 @@ PostPrepare_PgStat_Relations(PgStat_SubXactStatus *xact_state)
  * Load the saved counts into our local pgstats state.
  */
 void
-pgstat_twophase_postcommit(TransactionId xid, uint16 info,
+pgstat_twophase_postcommit(FullTransactionId fxid, uint16 info,
 						   void *recdata, uint32 len)
 {
 	TwoPhasePgStatRecord *rec = (TwoPhasePgStatRecord *) recdata;
@@ -780,7 +780,7 @@ pgstat_twophase_postcommit(TransactionId xid, uint16 info,
  * as aborted.
  */
 void
-pgstat_twophase_postabort(TransactionId xid, uint16 info,
+pgstat_twophase_postabort(FullTransactionId fxid, uint16 info,
 						  void *recdata, uint32 len)
 {
 	TwoPhasePgStatRecord *rec = (TwoPhasePgStatRecord *) recdata;
diff --git a/src/backend/utils/activity/pgstat_slru.c b/src/backend/utils/activity/pgstat_slru.c
index b9e940dde45b6..7bd8744accb0e 100644
--- a/src/backend/utils/activity/pgstat_slru.c
+++ b/src/backend/utils/activity/pgstat_slru.c
@@ -143,15 +143,6 @@ pgstat_get_slru_index(const char *name)
 	return (SLRU_NUM_ELEMENTS - 1);
 }
 
-/*
- * Check if there are any SLRU stats entries waiting for flush.
- */
-bool
-pgstat_slru_have_pending_cb(void)
-{
-	return have_slrustats;
-}
-
 /*
  * Flush out locally pending SLRU stats entries
  *
@@ -247,6 +238,7 @@ get_slru_entry(int slru_idx)
 	Assert((slru_idx >= 0) && (slru_idx < SLRU_NUM_ELEMENTS));
 
 	have_slrustats = true;
+	pgstat_report_fixed = true;
 
 	return &pending_SLRUStats[slru_idx];
 }
diff --git a/src/backend/utils/activity/pgstat_wal.c b/src/backend/utils/activity/pgstat_wal.c
index 16a1ecb4d90d2..0d04480d2f6d0 100644
--- a/src/backend/utils/activity/pgstat_wal.c
+++ b/src/backend/utils/activity/pgstat_wal.c
@@ -71,6 +71,15 @@ pgstat_fetch_stat_wal(void)
 	return &pgStatLocal.snapshot.wal;
 }
 
+/*
+ * To determine whether WAL usage happened.
+ */
+static inline bool
+pgstat_wal_have_pending(void)
+{
+	return pgWalUsage.wal_records != prevWalUsage.wal_records;
+}
+
 /*
  * Calculate how much WAL usage counters have increased by subtracting the
  * previous counters from the current ones.
@@ -92,7 +101,7 @@ pgstat_wal_flush_cb(bool nowait)
 	 * This function can be called even if nothing at all has happened. Avoid
 	 * taking lock for nothing in that case.
 	 */
-	if (!pgstat_wal_have_pending_cb())
+	if (!pgstat_wal_have_pending())
 		return false;
 
 	/*
@@ -136,15 +145,6 @@ pgstat_wal_init_backend_cb(void)
 	prevWalUsage = pgWalUsage;
 }
 
-/*
- * To determine whether WAL usage happened.
- */
-bool
-pgstat_wal_have_pending_cb(void)
-{
-	return pgWalUsage.wal_records != prevWalUsage.wal_records;
-}
-
 void
 pgstat_wal_init_shmem_cb(void *stats)
 {
diff --git a/src/backend/utils/activity/wait_event_names.txt b/src/backend/utils/activity/wait_event_names.txt
index 4da68312b5f97..0be307d2ca04b 100644
--- a/src/backend/utils/activity/wait_event_names.txt
+++ b/src/backend/utils/activity/wait_event_names.txt
@@ -356,9 +356,13 @@ AioWorkerSubmissionQueue	"Waiting to access AIO worker submission queue."
 #
 # END OF PREDEFINED LWLOCKS (DO NOT CHANGE THIS LINE)
 #
-# Predefined LWLocks (i.e., those declared in lwlocknames.h) must be listed
-# in the section above and must be listed in the same order as in
-# lwlocknames.h.  Other LWLocks must be listed in the section below.
+# Predefined LWLocks (i.e., those declared at the top of lwlocknames.h) must be
+# listed in the section above and must be listed in the same order as in
+# lwlocknames.h.
+#
+# Likewise, the built-in LWLock tranches (i.e., those declared at the bottom of
+# lwlocknames.h) must be listed in the section below and must be listed in the
+# same order as in lwlocknames.h.
 #
 
 XactBuffer	"Waiting for I/O on a transaction status SLRU buffer."
diff --git a/src/backend/utils/adt/Makefile b/src/backend/utils/adt/Makefile
index 4a233b63c3280..ffeacf2b819f3 100644
--- a/src/backend/utils/adt/Makefile
+++ b/src/backend/utils/adt/Makefile
@@ -23,6 +23,7 @@ OBJS = \
 	arrayutils.o \
 	ascii.o \
 	bool.o \
+	bytea.o \
 	cash.o \
 	char.o \
 	cryptohashfuncs.o \
diff --git a/src/backend/utils/adt/acl.c b/src/backend/utils/adt/acl.c
index ca3c5ee3df3ae..1213f9106d515 100644
--- a/src/backend/utils/adt/acl.c
+++ b/src/backend/utils/adt/acl.c
@@ -134,6 +134,22 @@ static AclResult pg_role_aclcheck(Oid role_oid, Oid roleid, AclMode mode);
 static void RoleMembershipCacheCallback(Datum arg, int cacheid, uint32 hashvalue);
 
 
+/*
+ * Test whether an identifier char can be left unquoted in ACLs.
+ *
+ * Formerly, we used isalnum() even on non-ASCII characters, resulting in
+ * unportable behavior.  To ensure dump compatibility with old versions,
+ * we now treat high-bit-set characters as always requiring quoting during
+ * putid(), but getid() will always accept them without quotes.
+ */
+static inline bool
+is_safe_acl_char(unsigned char c, bool is_getid)
+{
+	if (IS_HIGHBIT_SET(c))
+		return is_getid;
+	return isalnum(c) || c == '_';
+}
+
 /*
  * getid
  *		Consumes the first alphanumeric string (identifier) found in string
@@ -159,21 +175,22 @@ getid(const char *s, char *n, Node *escontext)
 
 	while (isspace((unsigned char) *s))
 		s++;
-	/* This code had better match what putid() does, below */
 	for (;
 		 *s != '\0' &&
-		 (isalnum((unsigned char) *s) ||
-		  *s == '_' ||
-		  *s == '"' ||
-		  in_quotes);
+		 (in_quotes || *s == '"' || is_safe_acl_char(*s, true));
 		 s++)
 	{
 		if (*s == '"')
 		{
+			if (!in_quotes)
+			{
+				in_quotes = true;
+				continue;
+			}
 			/* safe to look at next char (could be '\0' though) */
 			if (*(s + 1) != '"')
 			{
-				in_quotes = !in_quotes;
+				in_quotes = false;
 				continue;
 			}
 			/* it's an escaped double quote; skip the escaping char */
@@ -207,10 +224,10 @@ putid(char *p, const char *s)
 	const char *src;
 	bool		safe = true;
 
+	/* Detect whether we need to use double quotes */
 	for (src = s; *src; src++)
 	{
-		/* This test had better match what getid() does, above */
-		if (!isalnum((unsigned char) *src) && *src != '_')
+		if (!is_safe_acl_char(*src, false))
 		{
 			safe = false;
 			break;
diff --git a/src/backend/utils/adt/bytea.c b/src/backend/utils/adt/bytea.c
new file mode 100644
index 0000000000000..6e7b914c56395
--- /dev/null
+++ b/src/backend/utils/adt/bytea.c
@@ -0,0 +1,1114 @@
+/*-------------------------------------------------------------------------
+ *
+ * bytea.c
+ *	  Functions for the bytea type.
+ *
+ * Portions Copyright (c) 2025, PostgreSQL Global Development Group
+ *
+ *
+ * IDENTIFICATION
+ *	  src/backend/utils/adt/bytea.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#include "access/detoast.h"
+#include "catalog/pg_collation_d.h"
+#include "catalog/pg_type_d.h"
+#include "common/int.h"
+#include "fmgr.h"
+#include "libpq/pqformat.h"
+#include "port/pg_bitutils.h"
+#include "utils/builtins.h"
+#include "utils/bytea.h"
+#include "utils/fmgrprotos.h"
+#include "utils/memutils.h"
+#include "utils/sortsupport.h"
+#include "utils/varlena.h"
+#include "varatt.h"
+
+/* GUC variable */
+int			bytea_output = BYTEA_OUTPUT_HEX;
+
+static bytea *bytea_catenate(bytea *t1, bytea *t2);
+static bytea *bytea_substring(Datum str, int S, int L,
+							  bool length_not_specified);
+static bytea *bytea_overlay(bytea *t1, bytea *t2, int sp, int sl);
+
+/*
+ * bytea_catenate
+ *	Guts of byteacat(), broken out so it can be used by other functions
+ *
+ * Arguments can be in short-header form, but not compressed or out-of-line
+ */
+static bytea *
+bytea_catenate(bytea *t1, bytea *t2)
+{
+	bytea	   *result;
+	int			len1,
+				len2,
+				len;
+	char	   *ptr;
+
+	len1 = VARSIZE_ANY_EXHDR(t1);
+	len2 = VARSIZE_ANY_EXHDR(t2);
+
+	/* paranoia ... probably should throw error instead? */
+	if (len1 < 0)
+		len1 = 0;
+	if (len2 < 0)
+		len2 = 0;
+
+	len = len1 + len2 + VARHDRSZ;
+	result = (bytea *) palloc(len);
+
+	/* Set size of result string... */
+	SET_VARSIZE(result, len);
+
+	/* Fill data field of result string... */
+	ptr = VARDATA(result);
+	if (len1 > 0)
+		memcpy(ptr, VARDATA_ANY(t1), len1);
+	if (len2 > 0)
+		memcpy(ptr + len1, VARDATA_ANY(t2), len2);
+
+	return result;
+}
+
+#define PG_STR_GET_BYTEA(str_) \
+	DatumGetByteaPP(DirectFunctionCall1(byteain, CStringGetDatum(str_)))
+
+static bytea *
+bytea_substring(Datum str,
+				int S,
+				int L,
+				bool length_not_specified)
+{
+	int32		S1;				/* adjusted start position */
+	int32		L1;				/* adjusted substring length */
+	int32		E;				/* end position */
+
+	/*
+	 * The logic here should generally match text_substring().
+	 */
+	S1 = Max(S, 1);
+
+	if (length_not_specified)
+	{
+		/*
+		 * Not passed a length - DatumGetByteaPSlice() grabs everything to the
+		 * end of the string if we pass it a negative value for length.
+		 */
+		L1 = -1;
+	}
+	else if (L < 0)
+	{
+		/* SQL99 says to throw an error for E < S, i.e., negative length */
+		ereport(ERROR,
+				(errcode(ERRCODE_SUBSTRING_ERROR),
+				 errmsg("negative substring length not allowed")));
+		L1 = -1;				/* silence stupider compilers */
+	}
+	else if (pg_add_s32_overflow(S, L, &E))
+	{
+		/*
+		 * L could be large enough for S + L to overflow, in which case the
+		 * substring must run to end of string.
+		 */
+		L1 = -1;
+	}
+	else
+	{
+		/*
+		 * A zero or negative value for the end position can happen if the
+		 * start was negative or one. SQL99 says to return a zero-length
+		 * string.
+		 */
+		if (E < 1)
+			return PG_STR_GET_BYTEA("");
+
+		L1 = E - S1;
+	}
+
+	/*
+	 * If the start position is past the end of the string, SQL99 says to
+	 * return a zero-length string -- DatumGetByteaPSlice() will do that for
+	 * us.  We need only convert S1 to zero-based starting position.
+	 */
+	return DatumGetByteaPSlice(str, S1 - 1, L1);
+}
+
+static bytea *
+bytea_overlay(bytea *t1, bytea *t2, int sp, int sl)
+{
+	bytea	   *result;
+	bytea	   *s1;
+	bytea	   *s2;
+	int			sp_pl_sl;
+
+	/*
+	 * Check for possible integer-overflow cases.  For negative sp, throw a
+	 * "substring length" error because that's what should be expected
+	 * according to the spec's definition of OVERLAY().
+	 */
+	if (sp <= 0)
+		ereport(ERROR,
+				(errcode(ERRCODE_SUBSTRING_ERROR),
+				 errmsg("negative substring length not allowed")));
+	if (pg_add_s32_overflow(sp, sl, &sp_pl_sl))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("integer out of range")));
+
+	s1 = bytea_substring(PointerGetDatum(t1), 1, sp - 1, false);
+	s2 = bytea_substring(PointerGetDatum(t1), sp_pl_sl, -1, true);
+	result = bytea_catenate(s1, t2);
+	result = bytea_catenate(result, s2);
+
+	return result;
+}
+
+/*****************************************************************************
+ *	 USER I/O ROUTINES														 *
+ *****************************************************************************/
+
+#define VAL(CH)			((CH) - '0')
+#define DIG(VAL)		((VAL) + '0')
+
+/*
+ *		byteain			- converts from printable representation of byte array
+ *
+ *		Non-printable characters must be passed as '\nnn' (octal) and are
+ *		converted to internal form.  '\' must be passed as '\\'.
+ */
+Datum
+byteain(PG_FUNCTION_ARGS)
+{
+	char	   *inputText = PG_GETARG_CSTRING(0);
+	Node	   *escontext = fcinfo->context;
+	size_t		len = strlen(inputText);
+	size_t		bc;
+	char	   *tp;
+	char	   *rp;
+	bytea	   *result;
+
+	/* Recognize hex input */
+	if (inputText[0] == '\\' && inputText[1] == 'x')
+	{
+		bc = (len - 2) / 2 + VARHDRSZ;	/* maximum possible length */
+		result = palloc(bc);
+		bc = hex_decode_safe(inputText + 2, len - 2, VARDATA(result),
+							 escontext);
+		SET_VARSIZE(result, bc + VARHDRSZ); /* actual length */
+
+		PG_RETURN_BYTEA_P(result);
+	}
+
+	/* Else, it's the traditional escaped style */
+	result = (bytea *) palloc(len + VARHDRSZ);	/* maximum possible length */
+
+	tp = inputText;
+	rp = VARDATA(result);
+	while (*tp != '\0')
+	{
+		if (tp[0] != '\\')
+			*rp++ = *tp++;
+		else if ((tp[1] >= '0' && tp[1] <= '3') &&
+				 (tp[2] >= '0' && tp[2] <= '7') &&
+				 (tp[3] >= '0' && tp[3] <= '7'))
+		{
+			int			v;
+
+			v = VAL(tp[1]);
+			v <<= 3;
+			v += VAL(tp[2]);
+			v <<= 3;
+			*rp++ = v + VAL(tp[3]);
+
+			tp += 4;
+		}
+		else if (tp[1] == '\\')
+		{
+			*rp++ = '\\';
+			tp += 2;
+		}
+		else
+		{
+			/*
+			 * one backslash, not followed by another or ### valid octal
+			 */
+			ereturn(escontext, (Datum) 0,
+					(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+					 errmsg("invalid input syntax for type %s", "bytea")));
+		}
+	}
+
+	bc = rp - VARDATA(result);	/* actual length */
+	SET_VARSIZE(result, bc + VARHDRSZ);
+
+	PG_RETURN_BYTEA_P(result);
+}
+
+/*
+ *		byteaout		- converts to printable representation of byte array
+ *
+ *		In the traditional escaped format, non-printable characters are
+ *		printed as '\nnn' (octal) and '\' as '\\'.
+ */
+Datum
+byteaout(PG_FUNCTION_ARGS)
+{
+	bytea	   *vlena = PG_GETARG_BYTEA_PP(0);
+	char	   *result;
+	char	   *rp;
+
+	if (bytea_output == BYTEA_OUTPUT_HEX)
+	{
+		/* Print hex format */
+		rp = result = palloc(VARSIZE_ANY_EXHDR(vlena) * 2 + 2 + 1);
+		*rp++ = '\\';
+		*rp++ = 'x';
+		rp += hex_encode(VARDATA_ANY(vlena), VARSIZE_ANY_EXHDR(vlena), rp);
+	}
+	else if (bytea_output == BYTEA_OUTPUT_ESCAPE)
+	{
+		/* Print traditional escaped format */
+		char	   *vp;
+		uint64		len;
+		int			i;
+
+		len = 1;				/* empty string has 1 char */
+		vp = VARDATA_ANY(vlena);
+		for (i = VARSIZE_ANY_EXHDR(vlena); i != 0; i--, vp++)
+		{
+			if (*vp == '\\')
+				len += 2;
+			else if ((unsigned char) *vp < 0x20 || (unsigned char) *vp > 0x7e)
+				len += 4;
+			else
+				len++;
+		}
+
+		/*
+		 * In principle len can't overflow uint32 if the input fit in 1GB, but
+		 * for safety let's check rather than relying on palloc's internal
+		 * check.
+		 */
+		if (len > MaxAllocSize)
+			ereport(ERROR,
+					(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+					 errmsg_internal("result of bytea output conversion is too large")));
+		rp = result = (char *) palloc(len);
+
+		vp = VARDATA_ANY(vlena);
+		for (i = VARSIZE_ANY_EXHDR(vlena); i != 0; i--, vp++)
+		{
+			if (*vp == '\\')
+			{
+				*rp++ = '\\';
+				*rp++ = '\\';
+			}
+			else if ((unsigned char) *vp < 0x20 || (unsigned char) *vp > 0x7e)
+			{
+				int			val;	/* holds unprintable chars */
+
+				val = *vp;
+				rp[0] = '\\';
+				rp[3] = DIG(val & 07);
+				val >>= 3;
+				rp[2] = DIG(val & 07);
+				val >>= 3;
+				rp[1] = DIG(val & 03);
+				rp += 4;
+			}
+			else
+				*rp++ = *vp;
+		}
+	}
+	else
+	{
+		elog(ERROR, "unrecognized \"bytea_output\" setting: %d",
+			 bytea_output);
+		rp = result = NULL;		/* keep compiler quiet */
+	}
+	*rp = '\0';
+	PG_RETURN_CSTRING(result);
+}
+
+/*
+ *		bytearecv			- converts external binary format to bytea
+ */
+Datum
+bytearecv(PG_FUNCTION_ARGS)
+{
+	StringInfo	buf = (StringInfo) PG_GETARG_POINTER(0);
+	bytea	   *result;
+	int			nbytes;
+
+	nbytes = buf->len - buf->cursor;
+	result = (bytea *) palloc(nbytes + VARHDRSZ);
+	SET_VARSIZE(result, nbytes + VARHDRSZ);
+	pq_copymsgbytes(buf, VARDATA(result), nbytes);
+	PG_RETURN_BYTEA_P(result);
+}
+
+/*
+ *		byteasend			- converts bytea to binary format
+ *
+ * This is a special case: just copy the input...
+ */
+Datum
+byteasend(PG_FUNCTION_ARGS)
+{
+	bytea	   *vlena = PG_GETARG_BYTEA_P_COPY(0);
+
+	PG_RETURN_BYTEA_P(vlena);
+}
+
+Datum
+bytea_string_agg_transfn(PG_FUNCTION_ARGS)
+{
+	StringInfo	state;
+
+	state = PG_ARGISNULL(0) ? NULL : (StringInfo) PG_GETARG_POINTER(0);
+
+	/* Append the value unless null, preceding it with the delimiter. */
+	if (!PG_ARGISNULL(1))
+	{
+		bytea	   *value = PG_GETARG_BYTEA_PP(1);
+		bool		isfirst = false;
+
+		/*
+		 * You might think we can just throw away the first delimiter, however
+		 * we must keep it as we may be a parallel worker doing partial
+		 * aggregation building a state to send to the main process.  We need
+		 * to keep the delimiter of every aggregation so that the combine
+		 * function can properly join up the strings of two separately
+		 * partially aggregated results.  The first delimiter is only stripped
+		 * off in the final function.  To know how much to strip off the front
+		 * of the string, we store the length of the first delimiter in the
+		 * StringInfo's cursor field, which we don't otherwise need here.
+		 */
+		if (state == NULL)
+		{
+			MemoryContext aggcontext;
+			MemoryContext oldcontext;
+
+			if (!AggCheckCallContext(fcinfo, &aggcontext))
+			{
+				/* cannot be called directly because of internal-type argument */
+				elog(ERROR, "bytea_string_agg_transfn called in non-aggregate context");
+			}
+
+			/*
+			 * Create state in aggregate context.  It'll stay there across
+			 * subsequent calls.
+			 */
+			oldcontext = MemoryContextSwitchTo(aggcontext);
+			state = makeStringInfo();
+			MemoryContextSwitchTo(oldcontext);
+
+			isfirst = true;
+		}
+
+		if (!PG_ARGISNULL(2))
+		{
+			bytea	   *delim = PG_GETARG_BYTEA_PP(2);
+
+			appendBinaryStringInfo(state, VARDATA_ANY(delim),
+								   VARSIZE_ANY_EXHDR(delim));
+			if (isfirst)
+				state->cursor = VARSIZE_ANY_EXHDR(delim);
+		}
+
+		appendBinaryStringInfo(state, VARDATA_ANY(value),
+							   VARSIZE_ANY_EXHDR(value));
+	}
+
+	/*
+	 * The transition type for string_agg() is declared to be "internal",
+	 * which is a pass-by-value type the same size as a pointer.
+	 */
+	if (state)
+		PG_RETURN_POINTER(state);
+	PG_RETURN_NULL();
+}
+
+Datum
+bytea_string_agg_finalfn(PG_FUNCTION_ARGS)
+{
+	StringInfo	state;
+
+	/* cannot be called directly because of internal-type argument */
+	Assert(AggCheckCallContext(fcinfo, NULL));
+
+	state = PG_ARGISNULL(0) ? NULL : (StringInfo) PG_GETARG_POINTER(0);
+
+	if (state != NULL)
+	{
+		/* As per comment in transfn, strip data before the cursor position */
+		bytea	   *result;
+		int			strippedlen = state->len - state->cursor;
+
+		result = (bytea *) palloc(strippedlen + VARHDRSZ);
+		SET_VARSIZE(result, strippedlen + VARHDRSZ);
+		memcpy(VARDATA(result), &state->data[state->cursor], strippedlen);
+		PG_RETURN_BYTEA_P(result);
+	}
+	else
+		PG_RETURN_NULL();
+}
+
+/*-------------------------------------------------------------
+ * byteaoctetlen
+ *
+ * get the number of bytes contained in an instance of type 'bytea'
+ *-------------------------------------------------------------
+ */
+Datum
+byteaoctetlen(PG_FUNCTION_ARGS)
+{
+	Datum		str = PG_GETARG_DATUM(0);
+
+	/* We need not detoast the input at all */
+	PG_RETURN_INT32(toast_raw_datum_size(str) - VARHDRSZ);
+}
+
+/*
+ * byteacat -
+ *	  takes two bytea* and returns a bytea* that is the concatenation of
+ *	  the two.
+ *
+ * Cloned from textcat and modified as required.
+ */
+Datum
+byteacat(PG_FUNCTION_ARGS)
+{
+	bytea	   *t1 = PG_GETARG_BYTEA_PP(0);
+	bytea	   *t2 = PG_GETARG_BYTEA_PP(1);
+
+	PG_RETURN_BYTEA_P(bytea_catenate(t1, t2));
+}
+
+/*
+ * byteaoverlay
+ *	Replace specified substring of first string with second
+ *
+ * The SQL standard defines OVERLAY() in terms of substring and concatenation.
+ * This code is a direct implementation of what the standard says.
+ */
+Datum
+byteaoverlay(PG_FUNCTION_ARGS)
+{
+	bytea	   *t1 = PG_GETARG_BYTEA_PP(0);
+	bytea	   *t2 = PG_GETARG_BYTEA_PP(1);
+	int			sp = PG_GETARG_INT32(2);	/* substring start position */
+	int			sl = PG_GETARG_INT32(3);	/* substring length */
+
+	PG_RETURN_BYTEA_P(bytea_overlay(t1, t2, sp, sl));
+}
+
+Datum
+byteaoverlay_no_len(PG_FUNCTION_ARGS)
+{
+	bytea	   *t1 = PG_GETARG_BYTEA_PP(0);
+	bytea	   *t2 = PG_GETARG_BYTEA_PP(1);
+	int			sp = PG_GETARG_INT32(2);	/* substring start position */
+	int			sl;
+
+	sl = VARSIZE_ANY_EXHDR(t2); /* defaults to length(t2) */
+	PG_RETURN_BYTEA_P(bytea_overlay(t1, t2, sp, sl));
+}
+
+/*
+ * bytea_substr()
+ * Return a substring starting at the specified position.
+ * Cloned from text_substr and modified as required.
+ *
+ * Input:
+ *	- string
+ *	- starting position (is one-based)
+ *	- string length (optional)
+ *
+ * If the starting position is zero or less, then return from the start of the string
+ * adjusting the length to be consistent with the "negative start" per SQL.
+ * If the length is less than zero, an ERROR is thrown. If no third argument
+ * (length) is provided, the length to the end of the string is assumed.
+ */
+Datum
+bytea_substr(PG_FUNCTION_ARGS)
+{
+	PG_RETURN_BYTEA_P(bytea_substring(PG_GETARG_DATUM(0),
+									  PG_GETARG_INT32(1),
+									  PG_GETARG_INT32(2),
+									  false));
+}
+
+/*
+ * bytea_substr_no_len -
+ *	  Wrapper to avoid opr_sanity failure due to
+ *	  one function accepting a different number of args.
+ */
+Datum
+bytea_substr_no_len(PG_FUNCTION_ARGS)
+{
+	PG_RETURN_BYTEA_P(bytea_substring(PG_GETARG_DATUM(0),
+									  PG_GETARG_INT32(1),
+									  -1,
+									  true));
+}
+
+/*
+ * bit_count
+ */
+Datum
+bytea_bit_count(PG_FUNCTION_ARGS)
+{
+	bytea	   *t1 = PG_GETARG_BYTEA_PP(0);
+
+	PG_RETURN_INT64(pg_popcount(VARDATA_ANY(t1), VARSIZE_ANY_EXHDR(t1)));
+}
+
+/*
+ * byteapos -
+ *	  Return the position of the specified substring.
+ *	  Implements the SQL POSITION() function.
+ * Cloned from textpos and modified as required.
+ */
+Datum
+byteapos(PG_FUNCTION_ARGS)
+{
+	bytea	   *t1 = PG_GETARG_BYTEA_PP(0);
+	bytea	   *t2 = PG_GETARG_BYTEA_PP(1);
+	int			pos;
+	int			px,
+				p;
+	int			len1,
+				len2;
+	char	   *p1,
+			   *p2;
+
+	len1 = VARSIZE_ANY_EXHDR(t1);
+	len2 = VARSIZE_ANY_EXHDR(t2);
+
+	if (len2 <= 0)
+		PG_RETURN_INT32(1);		/* result for empty pattern */
+
+	p1 = VARDATA_ANY(t1);
+	p2 = VARDATA_ANY(t2);
+
+	pos = 0;
+	px = (len1 - len2);
+	for (p = 0; p <= px; p++)
+	{
+		if ((*p2 == *p1) && (memcmp(p1, p2, len2) == 0))
+		{
+			pos = p + 1;
+			break;
+		};
+		p1++;
+	};
+
+	PG_RETURN_INT32(pos);
+}
+
+/*-------------------------------------------------------------
+ * byteaGetByte
+ *
+ * this routine treats "bytea" as an array of bytes.
+ * It returns the Nth byte (a number between 0 and 255).
+ *-------------------------------------------------------------
+ */
+Datum
+byteaGetByte(PG_FUNCTION_ARGS)
+{
+	bytea	   *v = PG_GETARG_BYTEA_PP(0);
+	int32		n = PG_GETARG_INT32(1);
+	int			len;
+	int			byte;
+
+	len = VARSIZE_ANY_EXHDR(v);
+
+	if (n < 0 || n >= len)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+				 errmsg("index %d out of valid range, 0..%d",
+						n, len - 1)));
+
+	byte = ((unsigned char *) VARDATA_ANY(v))[n];
+
+	PG_RETURN_INT32(byte);
+}
+
+/*-------------------------------------------------------------
+ * byteaGetBit
+ *
+ * This routine treats a "bytea" type like an array of bits.
+ * It returns the value of the Nth bit (0 or 1).
+ *
+ *-------------------------------------------------------------
+ */
+Datum
+byteaGetBit(PG_FUNCTION_ARGS)
+{
+	bytea	   *v = PG_GETARG_BYTEA_PP(0);
+	int64		n = PG_GETARG_INT64(1);
+	int			byteNo,
+				bitNo;
+	int			len;
+	int			byte;
+
+	len = VARSIZE_ANY_EXHDR(v);
+
+	if (n < 0 || n >= (int64) len * 8)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+				 errmsg("index %" PRId64 " out of valid range, 0..%" PRId64,
+						n, (int64) len * 8 - 1)));
+
+	/* n/8 is now known < len, so safe to cast to int */
+	byteNo = (int) (n / 8);
+	bitNo = (int) (n % 8);
+
+	byte = ((unsigned char *) VARDATA_ANY(v))[byteNo];
+
+	if (byte & (1 << bitNo))
+		PG_RETURN_INT32(1);
+	else
+		PG_RETURN_INT32(0);
+}
+
+/*-------------------------------------------------------------
+ * byteaSetByte
+ *
+ * Given an instance of type 'bytea' creates a new one with
+ * the Nth byte set to the given value.
+ *
+ *-------------------------------------------------------------
+ */
+Datum
+byteaSetByte(PG_FUNCTION_ARGS)
+{
+	bytea	   *res = PG_GETARG_BYTEA_P_COPY(0);
+	int32		n = PG_GETARG_INT32(1);
+	int32		newByte = PG_GETARG_INT32(2);
+	int			len;
+
+	len = VARSIZE(res) - VARHDRSZ;
+
+	if (n < 0 || n >= len)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+				 errmsg("index %d out of valid range, 0..%d",
+						n, len - 1)));
+
+	/*
+	 * Now set the byte.
+	 */
+	((unsigned char *) VARDATA(res))[n] = newByte;
+
+	PG_RETURN_BYTEA_P(res);
+}
+
+/*-------------------------------------------------------------
+ * byteaSetBit
+ *
+ * Given an instance of type 'bytea' creates a new one with
+ * the Nth bit set to the given value.
+ *
+ *-------------------------------------------------------------
+ */
+Datum
+byteaSetBit(PG_FUNCTION_ARGS)
+{
+	bytea	   *res = PG_GETARG_BYTEA_P_COPY(0);
+	int64		n = PG_GETARG_INT64(1);
+	int32		newBit = PG_GETARG_INT32(2);
+	int			len;
+	int			oldByte,
+				newByte;
+	int			byteNo,
+				bitNo;
+
+	len = VARSIZE(res) - VARHDRSZ;
+
+	if (n < 0 || n >= (int64) len * 8)
+		ereport(ERROR,
+				(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
+				 errmsg("index %" PRId64 " out of valid range, 0..%" PRId64,
+						n, (int64) len * 8 - 1)));
+
+	/* n/8 is now known < len, so safe to cast to int */
+	byteNo = (int) (n / 8);
+	bitNo = (int) (n % 8);
+
+	/*
+	 * sanity check!
+	 */
+	if (newBit != 0 && newBit != 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("new bit must be 0 or 1")));
+
+	/*
+	 * Update the byte.
+	 */
+	oldByte = ((unsigned char *) VARDATA(res))[byteNo];
+
+	if (newBit == 0)
+		newByte = oldByte & (~(1 << bitNo));
+	else
+		newByte = oldByte | (1 << bitNo);
+
+	((unsigned char *) VARDATA(res))[byteNo] = newByte;
+
+	PG_RETURN_BYTEA_P(res);
+}
+
+/*
+ * Return reversed bytea
+ */
+Datum
+bytea_reverse(PG_FUNCTION_ARGS)
+{
+	bytea	   *v = PG_GETARG_BYTEA_PP(0);
+	const char *p = VARDATA_ANY(v);
+	int			len = VARSIZE_ANY_EXHDR(v);
+	const char *endp = p + len;
+	bytea	   *result = palloc(len + VARHDRSZ);
+	char	   *dst = (char *) VARDATA(result) + len;
+
+	SET_VARSIZE(result, len + VARHDRSZ);
+
+	while (p < endp)
+		*(--dst) = *p++;
+
+	PG_RETURN_BYTEA_P(result);
+}
+
+
+/*****************************************************************************
+ *	Comparison Functions used for bytea
+ *
+ * Note: btree indexes need these routines not to leak memory; therefore,
+ * be careful to free working copies of toasted datums.  Most places don't
+ * need to be so careful.
+ *****************************************************************************/
+
+Datum
+byteaeq(PG_FUNCTION_ARGS)
+{
+	Datum		arg1 = PG_GETARG_DATUM(0);
+	Datum		arg2 = PG_GETARG_DATUM(1);
+	bool		result;
+	Size		len1,
+				len2;
+
+	/*
+	 * We can use a fast path for unequal lengths, which might save us from
+	 * having to detoast one or both values.
+	 */
+	len1 = toast_raw_datum_size(arg1);
+	len2 = toast_raw_datum_size(arg2);
+	if (len1 != len2)
+		result = false;
+	else
+	{
+		bytea	   *barg1 = DatumGetByteaPP(arg1);
+		bytea	   *barg2 = DatumGetByteaPP(arg2);
+
+		result = (memcmp(VARDATA_ANY(barg1), VARDATA_ANY(barg2),
+						 len1 - VARHDRSZ) == 0);
+
+		PG_FREE_IF_COPY(barg1, 0);
+		PG_FREE_IF_COPY(barg2, 1);
+	}
+
+	PG_RETURN_BOOL(result);
+}
+
+Datum
+byteane(PG_FUNCTION_ARGS)
+{
+	Datum		arg1 = PG_GETARG_DATUM(0);
+	Datum		arg2 = PG_GETARG_DATUM(1);
+	bool		result;
+	Size		len1,
+				len2;
+
+	/*
+	 * We can use a fast path for unequal lengths, which might save us from
+	 * having to detoast one or both values.
+	 */
+	len1 = toast_raw_datum_size(arg1);
+	len2 = toast_raw_datum_size(arg2);
+	if (len1 != len2)
+		result = true;
+	else
+	{
+		bytea	   *barg1 = DatumGetByteaPP(arg1);
+		bytea	   *barg2 = DatumGetByteaPP(arg2);
+
+		result = (memcmp(VARDATA_ANY(barg1), VARDATA_ANY(barg2),
+						 len1 - VARHDRSZ) != 0);
+
+		PG_FREE_IF_COPY(barg1, 0);
+		PG_FREE_IF_COPY(barg2, 1);
+	}
+
+	PG_RETURN_BOOL(result);
+}
+
+Datum
+bytealt(PG_FUNCTION_ARGS)
+{
+	bytea	   *arg1 = PG_GETARG_BYTEA_PP(0);
+	bytea	   *arg2 = PG_GETARG_BYTEA_PP(1);
+	int			len1,
+				len2;
+	int			cmp;
+
+	len1 = VARSIZE_ANY_EXHDR(arg1);
+	len2 = VARSIZE_ANY_EXHDR(arg2);
+
+	cmp = memcmp(VARDATA_ANY(arg1), VARDATA_ANY(arg2), Min(len1, len2));
+
+	PG_FREE_IF_COPY(arg1, 0);
+	PG_FREE_IF_COPY(arg2, 1);
+
+	PG_RETURN_BOOL((cmp < 0) || ((cmp == 0) && (len1 < len2)));
+}
+
+Datum
+byteale(PG_FUNCTION_ARGS)
+{
+	bytea	   *arg1 = PG_GETARG_BYTEA_PP(0);
+	bytea	   *arg2 = PG_GETARG_BYTEA_PP(1);
+	int			len1,
+				len2;
+	int			cmp;
+
+	len1 = VARSIZE_ANY_EXHDR(arg1);
+	len2 = VARSIZE_ANY_EXHDR(arg2);
+
+	cmp = memcmp(VARDATA_ANY(arg1), VARDATA_ANY(arg2), Min(len1, len2));
+
+	PG_FREE_IF_COPY(arg1, 0);
+	PG_FREE_IF_COPY(arg2, 1);
+
+	PG_RETURN_BOOL((cmp < 0) || ((cmp == 0) && (len1 <= len2)));
+}
+
+Datum
+byteagt(PG_FUNCTION_ARGS)
+{
+	bytea	   *arg1 = PG_GETARG_BYTEA_PP(0);
+	bytea	   *arg2 = PG_GETARG_BYTEA_PP(1);
+	int			len1,
+				len2;
+	int			cmp;
+
+	len1 = VARSIZE_ANY_EXHDR(arg1);
+	len2 = VARSIZE_ANY_EXHDR(arg2);
+
+	cmp = memcmp(VARDATA_ANY(arg1), VARDATA_ANY(arg2), Min(len1, len2));
+
+	PG_FREE_IF_COPY(arg1, 0);
+	PG_FREE_IF_COPY(arg2, 1);
+
+	PG_RETURN_BOOL((cmp > 0) || ((cmp == 0) && (len1 > len2)));
+}
+
+Datum
+byteage(PG_FUNCTION_ARGS)
+{
+	bytea	   *arg1 = PG_GETARG_BYTEA_PP(0);
+	bytea	   *arg2 = PG_GETARG_BYTEA_PP(1);
+	int			len1,
+				len2;
+	int			cmp;
+
+	len1 = VARSIZE_ANY_EXHDR(arg1);
+	len2 = VARSIZE_ANY_EXHDR(arg2);
+
+	cmp = memcmp(VARDATA_ANY(arg1), VARDATA_ANY(arg2), Min(len1, len2));
+
+	PG_FREE_IF_COPY(arg1, 0);
+	PG_FREE_IF_COPY(arg2, 1);
+
+	PG_RETURN_BOOL((cmp > 0) || ((cmp == 0) && (len1 >= len2)));
+}
+
+Datum
+byteacmp(PG_FUNCTION_ARGS)
+{
+	bytea	   *arg1 = PG_GETARG_BYTEA_PP(0);
+	bytea	   *arg2 = PG_GETARG_BYTEA_PP(1);
+	int			len1,
+				len2;
+	int			cmp;
+
+	len1 = VARSIZE_ANY_EXHDR(arg1);
+	len2 = VARSIZE_ANY_EXHDR(arg2);
+
+	cmp = memcmp(VARDATA_ANY(arg1), VARDATA_ANY(arg2), Min(len1, len2));
+	if ((cmp == 0) && (len1 != len2))
+		cmp = (len1 < len2) ? -1 : 1;
+
+	PG_FREE_IF_COPY(arg1, 0);
+	PG_FREE_IF_COPY(arg2, 1);
+
+	PG_RETURN_INT32(cmp);
+}
+
+Datum
+bytea_larger(PG_FUNCTION_ARGS)
+{
+	bytea	   *arg1 = PG_GETARG_BYTEA_PP(0);
+	bytea	   *arg2 = PG_GETARG_BYTEA_PP(1);
+	bytea	   *result;
+	int			len1,
+				len2;
+	int			cmp;
+
+	len1 = VARSIZE_ANY_EXHDR(arg1);
+	len2 = VARSIZE_ANY_EXHDR(arg2);
+
+	cmp = memcmp(VARDATA_ANY(arg1), VARDATA_ANY(arg2), Min(len1, len2));
+	result = ((cmp > 0) || ((cmp == 0) && (len1 > len2)) ? arg1 : arg2);
+
+	PG_RETURN_BYTEA_P(result);
+}
+
+Datum
+bytea_smaller(PG_FUNCTION_ARGS)
+{
+	bytea	   *arg1 = PG_GETARG_BYTEA_PP(0);
+	bytea	   *arg2 = PG_GETARG_BYTEA_PP(1);
+	bytea	   *result;
+	int			len1,
+				len2;
+	int			cmp;
+
+	len1 = VARSIZE_ANY_EXHDR(arg1);
+	len2 = VARSIZE_ANY_EXHDR(arg2);
+
+	cmp = memcmp(VARDATA_ANY(arg1), VARDATA_ANY(arg2), Min(len1, len2));
+	result = ((cmp < 0) || ((cmp == 0) && (len1 < len2)) ? arg1 : arg2);
+
+	PG_RETURN_BYTEA_P(result);
+}
+
+Datum
+bytea_sortsupport(PG_FUNCTION_ARGS)
+{
+	SortSupport ssup = (SortSupport) PG_GETARG_POINTER(0);
+	MemoryContext oldcontext;
+
+	oldcontext = MemoryContextSwitchTo(ssup->ssup_cxt);
+
+	/* Use generic string SortSupport, forcing "C" collation */
+	varstr_sortsupport(ssup, BYTEAOID, C_COLLATION_OID);
+
+	MemoryContextSwitchTo(oldcontext);
+
+	PG_RETURN_VOID();
+}
+
+/* Cast bytea -> int2 */
+Datum
+bytea_int2(PG_FUNCTION_ARGS)
+{
+	bytea	   *v = PG_GETARG_BYTEA_PP(0);
+	int			len = VARSIZE_ANY_EXHDR(v);
+	uint16		result;
+
+	/* Check that the byte array is not too long */
+	if (len > sizeof(result))
+		ereport(ERROR,
+				errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				errmsg("smallint out of range"));
+
+	/* Convert it to an integer; most significant bytes come first */
+	result = 0;
+	for (int i = 0; i < len; i++)
+	{
+		result <<= BITS_PER_BYTE;
+		result |= ((unsigned char *) VARDATA_ANY(v))[i];
+	}
+
+	PG_RETURN_INT16(result);
+}
+
+/* Cast bytea -> int4 */
+Datum
+bytea_int4(PG_FUNCTION_ARGS)
+{
+	bytea	   *v = PG_GETARG_BYTEA_PP(0);
+	int			len = VARSIZE_ANY_EXHDR(v);
+	uint32		result;
+
+	/* Check that the byte array is not too long */
+	if (len > sizeof(result))
+		ereport(ERROR,
+				errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				errmsg("integer out of range"));
+
+	/* Convert it to an integer; most significant bytes come first */
+	result = 0;
+	for (int i = 0; i < len; i++)
+	{
+		result <<= BITS_PER_BYTE;
+		result |= ((unsigned char *) VARDATA_ANY(v))[i];
+	}
+
+	PG_RETURN_INT32(result);
+}
+
+/* Cast bytea -> int8 */
+Datum
+bytea_int8(PG_FUNCTION_ARGS)
+{
+	bytea	   *v = PG_GETARG_BYTEA_PP(0);
+	int			len = VARSIZE_ANY_EXHDR(v);
+	uint64		result;
+
+	/* Check that the byte array is not too long */
+	if (len > sizeof(result))
+		ereport(ERROR,
+				errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				errmsg("bigint out of range"));
+
+	/* Convert it to an integer; most significant bytes come first */
+	result = 0;
+	for (int i = 0; i < len; i++)
+	{
+		result <<= BITS_PER_BYTE;
+		result |= ((unsigned char *) VARDATA_ANY(v))[i];
+	}
+
+	PG_RETURN_INT64(result);
+}
+
+/* Cast int2 -> bytea; can just use int2send() */
+Datum
+int2_bytea(PG_FUNCTION_ARGS)
+{
+	return int2send(fcinfo);
+}
+
+/* Cast int4 -> bytea; can just use int4send() */
+Datum
+int4_bytea(PG_FUNCTION_ARGS)
+{
+	return int4send(fcinfo);
+}
+
+/* Cast int8 -> bytea; can just use int8send() */
+Datum
+int8_bytea(PG_FUNCTION_ARGS)
+{
+	return int8send(fcinfo);
+}
diff --git a/src/backend/utils/adt/date.c b/src/backend/utils/adt/date.c
index 4227ab1a72bfb..344f58b92f7a2 100644
--- a/src/backend/utils/adt/date.c
+++ b/src/backend/utils/adt/date.c
@@ -1363,10 +1363,35 @@ timestamp_date(PG_FUNCTION_ARGS)
 {
 	Timestamp	timestamp = PG_GETARG_TIMESTAMP(0);
 	DateADT		result;
+
+	result = timestamp2date_opt_overflow(timestamp, NULL);
+	PG_RETURN_DATEADT(result);
+}
+
+/*
+ * Convert timestamp to date.
+ *
+ * On successful conversion, *overflow is set to zero if it's not NULL.
+ *
+ * If the timestamp is finite but out of the valid range for date, then:
+ * if overflow is NULL, we throw an out-of-range error.
+ * if overflow is not NULL, we store +1 or -1 there to indicate the sign
+ * of the overflow, and return the appropriate date infinity.
+ *
+ * Note: given the ranges of the types, overflow is only possible at
+ * the minimum end of the range, but we don't assume that in this code.
+ */
+DateADT
+timestamp2date_opt_overflow(Timestamp timestamp, int *overflow)
+{
+	DateADT		result;
 	struct pg_tm tt,
 			   *tm = &tt;
 	fsec_t		fsec;
 
+	if (overflow)
+		*overflow = 0;
+
 	if (TIMESTAMP_IS_NOBEGIN(timestamp))
 		DATE_NOBEGIN(result);
 	else if (TIMESTAMP_IS_NOEND(timestamp))
@@ -1374,14 +1399,30 @@ timestamp_date(PG_FUNCTION_ARGS)
 	else
 	{
 		if (timestamp2tm(timestamp, NULL, tm, &fsec, NULL, NULL) != 0)
+		{
+			if (overflow)
+			{
+				if (timestamp < 0)
+				{
+					*overflow = -1;
+					DATE_NOBEGIN(result);
+				}
+				else
+				{
+					*overflow = 1;	/* not actually reachable */
+					DATE_NOEND(result);
+				}
+				return result;
+			}
 			ereport(ERROR,
 					(errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
 					 errmsg("timestamp out of range")));
+		}
 
 		result = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - POSTGRES_EPOCH_JDATE;
 	}
 
-	PG_RETURN_DATEADT(result);
+	return result;
 }
 
 
@@ -1408,11 +1449,36 @@ timestamptz_date(PG_FUNCTION_ARGS)
 {
 	TimestampTz timestamp = PG_GETARG_TIMESTAMP(0);
 	DateADT		result;
+
+	result = timestamptz2date_opt_overflow(timestamp, NULL);
+	PG_RETURN_DATEADT(result);
+}
+
+/*
+ * Convert timestamptz to date.
+ *
+ * On successful conversion, *overflow is set to zero if it's not NULL.
+ *
+ * If the timestamptz is finite but out of the valid range for date, then:
+ * if overflow is NULL, we throw an out-of-range error.
+ * if overflow is not NULL, we store +1 or -1 there to indicate the sign
+ * of the overflow, and return the appropriate date infinity.
+ *
+ * Note: given the ranges of the types, overflow is only possible at
+ * the minimum end of the range, but we don't assume that in this code.
+ */
+DateADT
+timestamptz2date_opt_overflow(TimestampTz timestamp, int *overflow)
+{
+	DateADT		result;
 	struct pg_tm tt,
 			   *tm = &tt;
 	fsec_t		fsec;
 	int			tz;
 
+	if (overflow)
+		*overflow = 0;
+
 	if (TIMESTAMP_IS_NOBEGIN(timestamp))
 		DATE_NOBEGIN(result);
 	else if (TIMESTAMP_IS_NOEND(timestamp))
@@ -1420,14 +1486,30 @@ timestamptz_date(PG_FUNCTION_ARGS)
 	else
 	{
 		if (timestamp2tm(timestamp, &tz, tm, &fsec, NULL, NULL) != 0)
+		{
+			if (overflow)
+			{
+				if (timestamp < 0)
+				{
+					*overflow = -1;
+					DATE_NOBEGIN(result);
+				}
+				else
+				{
+					*overflow = 1;	/* not actually reachable */
+					DATE_NOEND(result);
+				}
+				return result;
+			}
 			ereport(ERROR,
 					(errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
 					 errmsg("timestamp out of range")));
+		}
 
 		result = date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) - POSTGRES_EPOCH_JDATE;
 	}
 
-	PG_RETURN_DATEADT(result);
+	return result;
 }
 
 
diff --git a/src/backend/utils/adt/float.c b/src/backend/utils/adt/float.c
index ba66a9c4ce63a..7b97d2be6caed 100644
--- a/src/backend/utils/adt/float.c
+++ b/src/backend/utils/adt/float.c
@@ -4067,8 +4067,9 @@ float84ge(PG_FUNCTION_ARGS)
  * with the specified characteristics. An operand smaller than the
  * lower bound is assigned to bucket 0. An operand greater than or equal
  * to the upper bound is assigned to an additional bucket (with number
- * count+1). We don't allow "NaN" for any of the float8 inputs, and we
- * don't allow either of the histogram bounds to be +/- infinity.
+ * count+1). We don't allow the histogram bounds to be NaN or +/- infinity,
+ * but we do allow those values for the operand (taking NaN to be larger
+ * than any other value, as we do in comparisons).
  */
 Datum
 width_bucket_float8(PG_FUNCTION_ARGS)
@@ -4084,12 +4085,11 @@ width_bucket_float8(PG_FUNCTION_ARGS)
 				(errcode(ERRCODE_INVALID_ARGUMENT_FOR_WIDTH_BUCKET_FUNCTION),
 				 errmsg("count must be greater than zero")));
 
-	if (isnan(operand) || isnan(bound1) || isnan(bound2))
+	if (isnan(bound1) || isnan(bound2))
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_ARGUMENT_FOR_WIDTH_BUCKET_FUNCTION),
-				 errmsg("operand, lower bound, and upper bound cannot be NaN")));
+				 errmsg("lower and upper bounds cannot be NaN")));
 
-	/* Note that we allow "operand" to be infinite */
 	if (isinf(bound1) || isinf(bound2))
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_ARGUMENT_FOR_WIDTH_BUCKET_FUNCTION),
@@ -4097,15 +4097,15 @@ width_bucket_float8(PG_FUNCTION_ARGS)
 
 	if (bound1 < bound2)
 	{
-		if (operand < bound1)
-			result = 0;
-		else if (operand >= bound2)
+		if (isnan(operand) || operand >= bound2)
 		{
 			if (pg_add_s32_overflow(count, 1, &result))
 				ereport(ERROR,
 						(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
 						 errmsg("integer out of range")));
 		}
+		else if (operand < bound1)
+			result = 0;
 		else
 		{
 			if (!isinf(bound2 - bound1))
@@ -4135,7 +4135,7 @@ width_bucket_float8(PG_FUNCTION_ARGS)
 	}
 	else if (bound1 > bound2)
 	{
-		if (operand > bound1)
+		if (isnan(operand) || operand > bound1)
 			result = 0;
 		else if (operand <= bound2)
 		{
diff --git a/src/backend/utils/adt/inet_net_pton.c b/src/backend/utils/adt/inet_net_pton.c
index ef2236d9f0430..3b0db2a379937 100644
--- a/src/backend/utils/adt/inet_net_pton.c
+++ b/src/backend/utils/adt/inet_net_pton.c
@@ -115,8 +115,7 @@ inet_cidr_pton_ipv4(const char *src, u_char *dst, size_t size)
 		src++;					/* skip x or X. */
 		while ((ch = *src++) != '\0' && isxdigit((unsigned char) ch))
 		{
-			if (isupper((unsigned char) ch))
-				ch = tolower((unsigned char) ch);
+			ch = pg_ascii_tolower((unsigned char) ch);
 			n = strchr(xdigits, ch) - xdigits;
 			assert(n >= 0 && n <= 15);
 			if (dirty == 0)
diff --git a/src/backend/utils/adt/jsonb_gin.c b/src/backend/utils/adt/jsonb_gin.c
index c1950792b5aea..9b56248cf0bee 100644
--- a/src/backend/utils/adt/jsonb_gin.c
+++ b/src/backend/utils/adt/jsonb_gin.c
@@ -896,8 +896,8 @@ gin_extract_jsonb_query(PG_FUNCTION_ARGS)
 				continue;
 			/* We rely on the array elements not being toasted */
 			entries[j++] = make_text_key(JGINFLAG_KEY,
-										 VARDATA_ANY(key_datums[i]),
-										 VARSIZE_ANY_EXHDR(key_datums[i]));
+										 VARDATA_ANY(DatumGetPointer(key_datums[i])),
+										 VARSIZE_ANY_EXHDR(DatumGetPointer(key_datums[i])));
 		}
 
 		*nentries = j;
diff --git a/src/backend/utils/adt/jsonb_op.c b/src/backend/utils/adt/jsonb_op.c
index fa5603f26e1d6..51d38e321fb2f 100644
--- a/src/backend/utils/adt/jsonb_op.c
+++ b/src/backend/utils/adt/jsonb_op.c
@@ -63,8 +63,8 @@ jsonb_exists_any(PG_FUNCTION_ARGS)
 
 		strVal.type = jbvString;
 		/* We rely on the array elements not being toasted */
-		strVal.val.string.val = VARDATA_ANY(key_datums[i]);
-		strVal.val.string.len = VARSIZE_ANY_EXHDR(key_datums[i]);
+		strVal.val.string.val = VARDATA_ANY(DatumGetPointer(key_datums[i]));
+		strVal.val.string.len = VARSIZE_ANY_EXHDR(DatumGetPointer(key_datums[i]));
 
 		if (findJsonbValueFromContainer(&jb->root,
 										JB_FOBJECT | JB_FARRAY,
@@ -96,8 +96,8 @@ jsonb_exists_all(PG_FUNCTION_ARGS)
 
 		strVal.type = jbvString;
 		/* We rely on the array elements not being toasted */
-		strVal.val.string.val = VARDATA_ANY(key_datums[i]);
-		strVal.val.string.len = VARSIZE_ANY_EXHDR(key_datums[i]);
+		strVal.val.string.val = VARDATA_ANY(DatumGetPointer(key_datums[i]));
+		strVal.val.string.len = VARSIZE_ANY_EXHDR(DatumGetPointer(key_datums[i]));
 
 		if (findJsonbValueFromContainer(&jb->root,
 										JB_FOBJECT | JB_FARRAY,
diff --git a/src/backend/utils/adt/jsonb_util.c b/src/backend/utils/adt/jsonb_util.c
index c8b6c15e05975..82b807d067a34 100644
--- a/src/backend/utils/adt/jsonb_util.c
+++ b/src/backend/utils/adt/jsonb_util.c
@@ -277,22 +277,16 @@ compareJsonbContainers(JsonbContainer *a, JsonbContainer *b)
 		else
 		{
 			/*
-			 * It's safe to assume that the types differed, and that the va
-			 * and vb values passed were set.
-			 *
-			 * If the two values were of the same container type, then there'd
-			 * have been a chance to observe the variation in the number of
-			 * elements/pairs (when processing WJB_BEGIN_OBJECT, say). They're
-			 * either two heterogeneously-typed containers, or a container and
-			 * some scalar type.
-			 *
-			 * We don't have to consider the WJB_END_ARRAY and WJB_END_OBJECT
-			 * cases here, because we would have seen the corresponding
-			 * WJB_BEGIN_ARRAY and WJB_BEGIN_OBJECT tokens first, and
-			 * concluded that they don't match.
+			 * It's not possible for one iterator to report end of array or
+			 * object while the other one reports something else, because we
+			 * would have detected a length mismatch when we processed the
+			 * container-start tokens above.  Likewise we can't see WJB_DONE
+			 * from one but not the other.  So we have two different-type
+			 * containers, or a container and some scalar type, or two
+			 * different scalar types.  Sort on the basis of the type code.
 			 */
-			Assert(ra != WJB_END_ARRAY && ra != WJB_END_OBJECT);
-			Assert(rb != WJB_END_ARRAY && rb != WJB_END_OBJECT);
+			Assert(ra != WJB_DONE && ra != WJB_END_ARRAY && ra != WJB_END_OBJECT);
+			Assert(rb != WJB_DONE && rb != WJB_END_ARRAY && rb != WJB_END_OBJECT);
 
 			Assert(va.type != vb.type);
 			Assert(va.type != jbvBinary);
@@ -852,15 +846,20 @@ JsonbIteratorInit(JsonbContainer *container)
  * It is our job to expand the jbvBinary representation without bothering them
  * with it.  However, clients should not take it upon themselves to touch array
  * or Object element/pair buffers, since their element/pair pointers are
- * garbage.  Also, *val will not be set when returning WJB_END_ARRAY or
- * WJB_END_OBJECT, on the assumption that it's only useful to access values
- * when recursing in.
+ * garbage.
+ *
+ * *val is not meaningful when the result is WJB_DONE, WJB_END_ARRAY or
+ * WJB_END_OBJECT.  However, we set val->type = jbvNull in those cases,
+ * so that callers may assume that val->type is always well-defined.
  */
 JsonbIteratorToken
 JsonbIteratorNext(JsonbIterator **it, JsonbValue *val, bool skipNested)
 {
 	if (*it == NULL)
+	{
+		val->type = jbvNull;
 		return WJB_DONE;
+	}
 
 	/*
 	 * When stepping into a nested container, we jump back here to start
@@ -898,6 +897,7 @@ JsonbIteratorNext(JsonbIterator **it, JsonbValue *val, bool skipNested)
 				 * nesting).
 				 */
 				*it = freeAndGetParent(*it);
+				val->type = jbvNull;
 				return WJB_END_ARRAY;
 			}
 
@@ -951,6 +951,7 @@ JsonbIteratorNext(JsonbIterator **it, JsonbValue *val, bool skipNested)
 				 * of nesting).
 				 */
 				*it = freeAndGetParent(*it);
+				val->type = jbvNull;
 				return WJB_END_OBJECT;
 			}
 			else
@@ -995,8 +996,10 @@ JsonbIteratorNext(JsonbIterator **it, JsonbValue *val, bool skipNested)
 				return WJB_VALUE;
 	}
 
-	elog(ERROR, "invalid iterator state");
-	return -1;
+	elog(ERROR, "invalid jsonb iterator state");
+	/* satisfy compilers that don't know that elog(ERROR) doesn't return */
+	val->type = jbvNull;
+	return WJB_DONE;
 }
 
 /*
diff --git a/src/backend/utils/adt/jsonfuncs.c b/src/backend/utils/adt/jsonfuncs.c
index bcb1720b6cde2..370456408bfba 100644
--- a/src/backend/utils/adt/jsonfuncs.c
+++ b/src/backend/utils/adt/jsonfuncs.c
@@ -4766,8 +4766,8 @@ jsonb_delete_array(PG_FUNCTION_ARGS)
 					continue;
 
 				/* We rely on the array elements not being toasted */
-				keyptr = VARDATA_ANY(keys_elems[i]);
-				keylen = VARSIZE_ANY_EXHDR(keys_elems[i]);
+				keyptr = VARDATA_ANY(DatumGetPointer(keys_elems[i]));
+				keylen = VARSIZE_ANY_EXHDR(DatumGetPointer(keys_elems[i]));
 				if (keylen == v.val.string.len &&
 					memcmp(keyptr, v.val.string.val, keylen) == 0)
 				{
diff --git a/src/backend/utils/adt/jsonpath_exec.c b/src/backend/utils/adt/jsonpath_exec.c
index dbab24737ef1f..407041b14a177 100644
--- a/src/backend/utils/adt/jsonpath_exec.c
+++ b/src/backend/utils/adt/jsonpath_exec.c
@@ -3074,8 +3074,8 @@ JsonItemFromDatum(Datum val, Oid typid, int32 typmod, JsonbValue *res)
 		case TEXTOID:
 		case VARCHAROID:
 			res->type = jbvString;
-			res->val.string.val = VARDATA_ANY(val);
-			res->val.string.len = VARSIZE_ANY_EXHDR(val);
+			res->val.string.val = VARDATA_ANY(DatumGetPointer(val));
+			res->val.string.len = VARSIZE_ANY_EXHDR(DatumGetPointer(val));
 			break;
 		case DATEOID:
 		case TIMEOID:
diff --git a/src/backend/utils/adt/like.c b/src/backend/utils/adt/like.c
index 7f4cf6145854a..4216ac17f4371 100644
--- a/src/backend/utils/adt/like.c
+++ b/src/backend/utils/adt/like.c
@@ -98,7 +98,7 @@ SB_lower_char(unsigned char c, pg_locale_t locale)
 	else if (locale->is_default)
 		return pg_tolower(c);
 	else
-		return tolower_l(c, locale->info.lt);
+		return char_tolower(c, locale);
 }
 
 
@@ -209,7 +209,17 @@ Generic_Text_IC_like(text *str, text *pat, Oid collation)
 	 * way.
 	 */
 
-	if (pg_database_encoding_max_length() > 1 || (locale->provider == COLLPROVIDER_ICU))
+	if (locale->ctype_is_c ||
+		(char_tolower_enabled(locale) &&
+		 pg_database_encoding_max_length() == 1))
+	{
+		p = VARDATA_ANY(pat);
+		plen = VARSIZE_ANY_EXHDR(pat);
+		s = VARDATA_ANY(str);
+		slen = VARSIZE_ANY_EXHDR(str);
+		return SB_IMatchText(s, slen, p, plen, locale);
+	}
+	else
 	{
 		pat = DatumGetTextPP(DirectFunctionCall1Coll(lower, collation,
 													 PointerGetDatum(pat)));
@@ -224,14 +234,6 @@ Generic_Text_IC_like(text *str, text *pat, Oid collation)
 		else
 			return MB_MatchText(s, slen, p, plen, 0);
 	}
-	else
-	{
-		p = VARDATA_ANY(pat);
-		plen = VARSIZE_ANY_EXHDR(pat);
-		s = VARDATA_ANY(str);
-		slen = VARSIZE_ANY_EXHDR(str);
-		return SB_IMatchText(s, slen, p, plen, locale);
-	}
 }
 
 /*
diff --git a/src/backend/utils/adt/like_support.c b/src/backend/utils/adt/like_support.c
index 8fdc677371f4d..999f23f86d51d 100644
--- a/src/backend/utils/adt/like_support.c
+++ b/src/backend/utils/adt/like_support.c
@@ -1495,13 +1495,8 @@ pattern_char_isalpha(char c, bool is_multibyte,
 {
 	if (locale->ctype_is_c)
 		return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z');
-	else if (is_multibyte && IS_HIGHBIT_SET(c))
-		return true;
-	else if (locale->provider != COLLPROVIDER_LIBC)
-		return IS_HIGHBIT_SET(c) ||
-			(c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z');
 	else
-		return isalpha_l((unsigned char) c, locale->info.lt);
+		return char_is_cased(c, locale);
 }
 
 
diff --git a/src/backend/utils/adt/meson.build b/src/backend/utils/adt/meson.build
index 244f48f4fd711..ed9bbd7b9266b 100644
--- a/src/backend/utils/adt/meson.build
+++ b/src/backend/utils/adt/meson.build
@@ -12,6 +12,7 @@ backend_sources += files(
   'arrayutils.c',
   'ascii.c',
   'bool.c',
+  'bytea.c',
   'cash.c',
   'char.c',
   'cryptohashfuncs.c',
diff --git a/src/backend/utils/adt/multirangetypes.c b/src/backend/utils/adt/multirangetypes.c
index cd84ced5b487c..46f2ec0c29fbd 100644
--- a/src/backend/utils/adt/multirangetypes.c
+++ b/src/backend/utils/adt/multirangetypes.c
@@ -394,12 +394,13 @@ multirange_send(PG_FUNCTION_ARGS)
 	for (int i = 0; i < range_count; i++)
 	{
 		Datum		range;
+		bytea	   *outputbytes;
 
 		range = RangeTypePGetDatum(ranges[i]);
-		range = PointerGetDatum(SendFunctionCall(&cache->typioproc, range));
+		outputbytes = SendFunctionCall(&cache->typioproc, range);
 
-		pq_sendint32(buf, VARSIZE(range) - VARHDRSZ);
-		pq_sendbytes(buf, VARDATA(range), VARSIZE(range) - VARHDRSZ);
+		pq_sendint32(buf, VARSIZE(outputbytes) - VARHDRSZ);
+		pq_sendbytes(buf, VARDATA(outputbytes), VARSIZE(outputbytes) - VARHDRSZ);
 	}
 
 	PG_RETURN_BYTEA_P(pq_endtypsend(buf));
@@ -2833,7 +2834,7 @@ hash_multirange(PG_FUNCTION_ARGS)
 			upper_hash = 0;
 
 		/* Merge hashes of flags and bounds */
-		range_hash = hash_uint32((uint32) flags);
+		range_hash = hash_bytes_uint32((uint32) flags);
 		range_hash ^= lower_hash;
 		range_hash = pg_rotate_left32(range_hash, 1);
 		range_hash ^= upper_hash;
diff --git a/src/backend/utils/adt/network.c b/src/backend/utils/adt/network.c
index f03fcc1147bb0..9fd211b2d4576 100644
--- a/src/backend/utils/adt/network.c
+++ b/src/backend/utils/adt/network.c
@@ -12,8 +12,6 @@
 #include <netinet/in.h>
 #include <arpa/inet.h>
 
-#include "access/stratnum.h"
-#include "catalog/pg_opfamily.h"
 #include "catalog/pg_type.h"
 #include "common/hashfn.h"
 #include "common/ip.h"
diff --git a/src/backend/utils/adt/network_spgist.c b/src/backend/utils/adt/network_spgist.c
index a84747d927586..602276a35c3ea 100644
--- a/src/backend/utils/adt/network_spgist.c
+++ b/src/backend/utils/adt/network_spgist.c
@@ -37,7 +37,6 @@
 #include "catalog/pg_type.h"
 #include "utils/fmgrprotos.h"
 #include "utils/inet.h"
-#include "varatt.h"
 
 
 static int	inet_spg_node_number(const inet *val, int commonbits);
diff --git a/src/backend/utils/adt/numeric.c b/src/backend/utils/adt/numeric.c
index 58ad1a65ef7b1..c9233565d57a7 100644
--- a/src/backend/utils/adt/numeric.c
+++ b/src/backend/utils/adt/numeric.c
@@ -1960,8 +1960,9 @@ generate_series_numeric_support(PG_FUNCTION_ARGS)
  * with the specified characteristics. An operand smaller than the
  * lower bound is assigned to bucket 0. An operand greater than or equal
  * to the upper bound is assigned to an additional bucket (with number
- * count+1). We don't allow "NaN" for any of the numeric inputs, and we
- * don't allow either of the histogram bounds to be +/- infinity.
+ * count+1). We don't allow the histogram bounds to be NaN or +/- infinity,
+ * but we do allow those values for the operand (taking NaN to be larger
+ * than any other value, as we do in comparisons).
  */
 Datum
 width_bucket_numeric(PG_FUNCTION_ARGS)
@@ -1979,17 +1980,13 @@ width_bucket_numeric(PG_FUNCTION_ARGS)
 				(errcode(ERRCODE_INVALID_ARGUMENT_FOR_WIDTH_BUCKET_FUNCTION),
 				 errmsg("count must be greater than zero")));
 
-	if (NUMERIC_IS_SPECIAL(operand) ||
-		NUMERIC_IS_SPECIAL(bound1) ||
-		NUMERIC_IS_SPECIAL(bound2))
+	if (NUMERIC_IS_SPECIAL(bound1) || NUMERIC_IS_SPECIAL(bound2))
 	{
-		if (NUMERIC_IS_NAN(operand) ||
-			NUMERIC_IS_NAN(bound1) ||
-			NUMERIC_IS_NAN(bound2))
+		if (NUMERIC_IS_NAN(bound1) || NUMERIC_IS_NAN(bound2))
 			ereport(ERROR,
 					(errcode(ERRCODE_INVALID_ARGUMENT_FOR_WIDTH_BUCKET_FUNCTION),
-					 errmsg("operand, lower bound, and upper bound cannot be NaN")));
-		/* We allow "operand" to be infinite; cmp_numerics will cope */
+					 errmsg("lower and upper bounds cannot be NaN")));
+
 		if (NUMERIC_IS_INF(bound1) || NUMERIC_IS_INF(bound2))
 			ereport(ERROR,
 					(errcode(ERRCODE_INVALID_ARGUMENT_FOR_WIDTH_BUCKET_FUNCTION),
diff --git a/src/backend/utils/adt/pg_locale.c b/src/backend/utils/adt/pg_locale.c
index f5e31c433a0de..97c2ac1faf9a4 100644
--- a/src/backend/utils/adt/pg_locale.c
+++ b/src/backend/utils/adt/pg_locale.c
@@ -41,7 +41,6 @@
 #include "mb/pg_wchar.h"
 #include "miscadmin.h"
 #include "utils/builtins.h"
-#include "utils/formatting.h"
 #include "utils/guc_hooks.h"
 #include "utils/lsyscache.h"
 #include "utils/memutils.h"
@@ -80,31 +79,6 @@ extern pg_locale_t create_pg_locale_icu(Oid collid, MemoryContext context);
 extern pg_locale_t create_pg_locale_libc(Oid collid, MemoryContext context);
 extern char *get_collation_actual_version_libc(const char *collcollate);
 
-extern size_t strlower_builtin(char *dst, size_t dstsize, const char *src,
-							   ssize_t srclen, pg_locale_t locale);
-extern size_t strtitle_builtin(char *dst, size_t dstsize, const char *src,
-							   ssize_t srclen, pg_locale_t locale);
-extern size_t strupper_builtin(char *dst, size_t dstsize, const char *src,
-							   ssize_t srclen, pg_locale_t locale);
-extern size_t strfold_builtin(char *dst, size_t dstsize, const char *src,
-							  ssize_t srclen, pg_locale_t locale);
-
-extern size_t strlower_icu(char *dst, size_t dstsize, const char *src,
-						   ssize_t srclen, pg_locale_t locale);
-extern size_t strtitle_icu(char *dst, size_t dstsize, const char *src,
-						   ssize_t srclen, pg_locale_t locale);
-extern size_t strupper_icu(char *dst, size_t dstsize, const char *src,
-						   ssize_t srclen, pg_locale_t locale);
-extern size_t strfold_icu(char *dst, size_t dstsize, const char *src,
-						  ssize_t srclen, pg_locale_t locale);
-
-extern size_t strlower_libc(char *dst, size_t dstsize, const char *src,
-							ssize_t srclen, pg_locale_t locale);
-extern size_t strtitle_libc(char *dst, size_t dstsize, const char *src,
-							ssize_t srclen, pg_locale_t locale);
-extern size_t strupper_libc(char *dst, size_t dstsize, const char *src,
-							ssize_t srclen, pg_locale_t locale);
-
 /* GUC settings */
 char	   *locale_messages;
 char	   *locale_monetary;
@@ -1093,6 +1067,9 @@ create_pg_locale(Oid collid, MemoryContext context)
 	Assert((result->collate_is_c && result->collate == NULL) ||
 		   (!result->collate_is_c && result->collate != NULL));
 
+	Assert((result->ctype_is_c && result->ctype == NULL) ||
+		   (!result->ctype_is_c && result->ctype != NULL));
+
 	datum = SysCacheGetAttr(COLLOID, tp, Anum_pg_collation_collversion,
 							&isnull);
 	if (!isnull)
@@ -1257,77 +1234,31 @@ size_t
 pg_strlower(char *dst, size_t dstsize, const char *src, ssize_t srclen,
 			pg_locale_t locale)
 {
-	if (locale->provider == COLLPROVIDER_BUILTIN)
-		return strlower_builtin(dst, dstsize, src, srclen, locale);
-#ifdef USE_ICU
-	else if (locale->provider == COLLPROVIDER_ICU)
-		return strlower_icu(dst, dstsize, src, srclen, locale);
-#endif
-	else if (locale->provider == COLLPROVIDER_LIBC)
-		return strlower_libc(dst, dstsize, src, srclen, locale);
-	else
-		/* shouldn't happen */
-		PGLOCALE_SUPPORT_ERROR(locale->provider);
-
-	return 0;					/* keep compiler quiet */
+	return locale->ctype->strlower(dst, dstsize, src, srclen, locale);
 }
 
 size_t
 pg_strtitle(char *dst, size_t dstsize, const char *src, ssize_t srclen,
 			pg_locale_t locale)
 {
-	if (locale->provider == COLLPROVIDER_BUILTIN)
-		return strtitle_builtin(dst, dstsize, src, srclen, locale);
-#ifdef USE_ICU
-	else if (locale->provider == COLLPROVIDER_ICU)
-		return strtitle_icu(dst, dstsize, src, srclen, locale);
-#endif
-	else if (locale->provider == COLLPROVIDER_LIBC)
-		return strtitle_libc(dst, dstsize, src, srclen, locale);
-	else
-		/* shouldn't happen */
-		PGLOCALE_SUPPORT_ERROR(locale->provider);
-
-	return 0;					/* keep compiler quiet */
+	return locale->ctype->strtitle(dst, dstsize, src, srclen, locale);
 }
 
 size_t
 pg_strupper(char *dst, size_t dstsize, const char *src, ssize_t srclen,
 			pg_locale_t locale)
 {
-	if (locale->provider == COLLPROVIDER_BUILTIN)
-		return strupper_builtin(dst, dstsize, src, srclen, locale);
-#ifdef USE_ICU
-	else if (locale->provider == COLLPROVIDER_ICU)
-		return strupper_icu(dst, dstsize, src, srclen, locale);
-#endif
-	else if (locale->provider == COLLPROVIDER_LIBC)
-		return strupper_libc(dst, dstsize, src, srclen, locale);
-	else
-		/* shouldn't happen */
-		PGLOCALE_SUPPORT_ERROR(locale->provider);
-
-	return 0;					/* keep compiler quiet */
+	return locale->ctype->strupper(dst, dstsize, src, srclen, locale);
 }
 
 size_t
 pg_strfold(char *dst, size_t dstsize, const char *src, ssize_t srclen,
 		   pg_locale_t locale)
 {
-	if (locale->provider == COLLPROVIDER_BUILTIN)
-		return strfold_builtin(dst, dstsize, src, srclen, locale);
-#ifdef USE_ICU
-	else if (locale->provider == COLLPROVIDER_ICU)
-		return strfold_icu(dst, dstsize, src, srclen, locale);
-#endif
-	/* for libc, just use strlower */
-	else if (locale->provider == COLLPROVIDER_LIBC)
-		return strlower_libc(dst, dstsize, src, srclen, locale);
+	if (locale->ctype->strfold)
+		return locale->ctype->strfold(dst, dstsize, src, srclen, locale);
 	else
-		/* shouldn't happen */
-		PGLOCALE_SUPPORT_ERROR(locale->provider);
-
-	return 0;					/* keep compiler quiet */
+		return locale->ctype->strlower(dst, dstsize, src, srclen, locale);
 }
 
 /*
@@ -1464,6 +1395,41 @@ pg_strnxfrm_prefix(char *dest, size_t destsize, const char *src,
 	return locale->collate->strnxfrm_prefix(dest, destsize, src, srclen, locale);
 }
 
+/*
+ * char_is_cased()
+ *
+ * Fuzzy test of whether the given char is case-varying or not. The argument
+ * is a single byte, so in a multibyte encoding, just assume any non-ASCII
+ * char is case-varying.
+ */
+bool
+char_is_cased(char ch, pg_locale_t locale)
+{
+	return locale->ctype->char_is_cased(ch, locale);
+}
+
+/*
+ * char_tolower_enabled()
+ *
+ * Does the provider support char_tolower()?
+ */
+bool
+char_tolower_enabled(pg_locale_t locale)
+{
+	return (locale->ctype->char_tolower != NULL);
+}
+
+/*
+ * char_tolower()
+ *
+ * Convert char (single-byte encoding) to lowercase.
+ */
+char
+char_tolower(unsigned char ch, pg_locale_t locale)
+{
+	return locale->ctype->char_tolower(ch, locale);
+}
+
 /*
  * Return required encoding ID for the given locale, or -1 if any encoding is
  * valid for the locale.
diff --git a/src/backend/utils/adt/pg_locale_builtin.c b/src/backend/utils/adt/pg_locale_builtin.c
index f51768830cd7b..0c9fbdb40f2a9 100644
--- a/src/backend/utils/adt/pg_locale_builtin.c
+++ b/src/backend/utils/adt/pg_locale_builtin.c
@@ -18,22 +18,12 @@
 #include "mb/pg_wchar.h"
 #include "miscadmin.h"
 #include "utils/builtins.h"
-#include "utils/memutils.h"
 #include "utils/pg_locale.h"
 #include "utils/syscache.h"
 
 extern pg_locale_t create_pg_locale_builtin(Oid collid,
 											MemoryContext context);
 extern char *get_collation_actual_version_builtin(const char *collcollate);
-extern size_t strlower_builtin(char *dest, size_t destsize, const char *src,
-							   ssize_t srclen, pg_locale_t locale);
-extern size_t strtitle_builtin(char *dest, size_t destsize, const char *src,
-							   ssize_t srclen, pg_locale_t locale);
-extern size_t strupper_builtin(char *dest, size_t destsize, const char *src,
-							   ssize_t srclen, pg_locale_t locale);
-extern size_t strfold_builtin(char *dest, size_t destsize, const char *src,
-							  ssize_t srclen, pg_locale_t locale);
-
 
 struct WordBoundaryState
 {
@@ -77,7 +67,7 @@ initcap_wbnext(void *state)
 	return wbstate->len;
 }
 
-size_t
+static size_t
 strlower_builtin(char *dest, size_t destsize, const char *src, ssize_t srclen,
 				 pg_locale_t locale)
 {
@@ -85,7 +75,7 @@ strlower_builtin(char *dest, size_t destsize, const char *src, ssize_t srclen,
 							locale->info.builtin.casemap_full);
 }
 
-size_t
+static size_t
 strtitle_builtin(char *dest, size_t destsize, const char *src, ssize_t srclen,
 				 pg_locale_t locale)
 {
@@ -103,7 +93,7 @@ strtitle_builtin(char *dest, size_t destsize, const char *src, ssize_t srclen,
 							initcap_wbnext, &wbstate);
 }
 
-size_t
+static size_t
 strupper_builtin(char *dest, size_t destsize, const char *src, ssize_t srclen,
 				 pg_locale_t locale)
 {
@@ -111,7 +101,7 @@ strupper_builtin(char *dest, size_t destsize, const char *src, ssize_t srclen,
 							locale->info.builtin.casemap_full);
 }
 
-size_t
+static size_t
 strfold_builtin(char *dest, size_t destsize, const char *src, ssize_t srclen,
 				pg_locale_t locale)
 {
@@ -119,6 +109,98 @@ strfold_builtin(char *dest, size_t destsize, const char *src, ssize_t srclen,
 						   locale->info.builtin.casemap_full);
 }
 
+static bool
+wc_isdigit_builtin(pg_wchar wc, pg_locale_t locale)
+{
+	return pg_u_isdigit(wc, !locale->info.builtin.casemap_full);
+}
+
+static bool
+wc_isalpha_builtin(pg_wchar wc, pg_locale_t locale)
+{
+	return pg_u_isalpha(wc);
+}
+
+static bool
+wc_isalnum_builtin(pg_wchar wc, pg_locale_t locale)
+{
+	return pg_u_isalnum(wc, !locale->info.builtin.casemap_full);
+}
+
+static bool
+wc_isupper_builtin(pg_wchar wc, pg_locale_t locale)
+{
+	return pg_u_isupper(wc);
+}
+
+static bool
+wc_islower_builtin(pg_wchar wc, pg_locale_t locale)
+{
+	return pg_u_islower(wc);
+}
+
+static bool
+wc_isgraph_builtin(pg_wchar wc, pg_locale_t locale)
+{
+	return pg_u_isgraph(wc);
+}
+
+static bool
+wc_isprint_builtin(pg_wchar wc, pg_locale_t locale)
+{
+	return pg_u_isprint(wc);
+}
+
+static bool
+wc_ispunct_builtin(pg_wchar wc, pg_locale_t locale)
+{
+	return pg_u_ispunct(wc, !locale->info.builtin.casemap_full);
+}
+
+static bool
+wc_isspace_builtin(pg_wchar wc, pg_locale_t locale)
+{
+	return pg_u_isspace(wc);
+}
+
+static bool
+char_is_cased_builtin(char ch, pg_locale_t locale)
+{
+	return IS_HIGHBIT_SET(ch) ||
+		(ch >= 'A' && ch <= 'Z') || (ch >= 'a' && ch <= 'z');
+}
+
+static pg_wchar
+wc_toupper_builtin(pg_wchar wc, pg_locale_t locale)
+{
+	return unicode_uppercase_simple(wc);
+}
+
+static pg_wchar
+wc_tolower_builtin(pg_wchar wc, pg_locale_t locale)
+{
+	return unicode_lowercase_simple(wc);
+}
+
+static const struct ctype_methods ctype_methods_builtin = {
+	.strlower = strlower_builtin,
+	.strtitle = strtitle_builtin,
+	.strupper = strupper_builtin,
+	.strfold = strfold_builtin,
+	.wc_isdigit = wc_isdigit_builtin,
+	.wc_isalpha = wc_isalpha_builtin,
+	.wc_isalnum = wc_isalnum_builtin,
+	.wc_isupper = wc_isupper_builtin,
+	.wc_islower = wc_islower_builtin,
+	.wc_isgraph = wc_isgraph_builtin,
+	.wc_isprint = wc_isprint_builtin,
+	.wc_ispunct = wc_ispunct_builtin,
+	.wc_isspace = wc_isspace_builtin,
+	.char_is_cased = char_is_cased_builtin,
+	.wc_tolower = wc_tolower_builtin,
+	.wc_toupper = wc_toupper_builtin,
+};
+
 pg_locale_t
 create_pg_locale_builtin(Oid collid, MemoryContext context)
 {
@@ -158,10 +240,11 @@ create_pg_locale_builtin(Oid collid, MemoryContext context)
 
 	result->info.builtin.locale = MemoryContextStrdup(context, locstr);
 	result->info.builtin.casemap_full = (strcmp(locstr, "PG_UNICODE_FAST") == 0);
-	result->provider = COLLPROVIDER_BUILTIN;
 	result->deterministic = true;
 	result->collate_is_c = true;
 	result->ctype_is_c = (strcmp(locstr, "C") == 0);
+	if (!result->ctype_is_c)
+		result->ctype = &ctype_methods_builtin;
 
 	return result;
 }
diff --git a/src/backend/utils/adt/pg_locale_icu.c b/src/backend/utils/adt/pg_locale_icu.c
index a32c32a0744bd..96741e08269a4 100644
--- a/src/backend/utils/adt/pg_locale_icu.c
+++ b/src/backend/utils/adt/pg_locale_icu.c
@@ -48,19 +48,22 @@
 #define		TEXTBUFLEN			1024
 
 extern pg_locale_t create_pg_locale_icu(Oid collid, MemoryContext context);
-extern size_t strlower_icu(char *dest, size_t destsize, const char *src,
-						   ssize_t srclen, pg_locale_t locale);
-extern size_t strtitle_icu(char *dest, size_t destsize, const char *src,
-						   ssize_t srclen, pg_locale_t locale);
-extern size_t strupper_icu(char *dest, size_t destsize, const char *src,
-						   ssize_t srclen, pg_locale_t locale);
-extern size_t strfold_icu(char *dest, size_t destsize, const char *src,
-						  ssize_t srclen, pg_locale_t locale);
 
 #ifdef USE_ICU
 
 extern UCollator *pg_ucol_open(const char *loc_str);
 
+static size_t strlower_icu(char *dest, size_t destsize, const char *src,
+						   ssize_t srclen, pg_locale_t locale);
+static size_t strtitle_icu(char *dest, size_t destsize, const char *src,
+						   ssize_t srclen, pg_locale_t locale);
+static size_t strupper_icu(char *dest, size_t destsize, const char *src,
+						   ssize_t srclen, pg_locale_t locale);
+static size_t strfold_icu(char *dest, size_t destsize, const char *src,
+						  ssize_t srclen, pg_locale_t locale);
+static int	strncoll_icu(const char *arg1, ssize_t len1,
+						 const char *arg2, ssize_t len2,
+						 pg_locale_t locale);
 static size_t strnxfrm_icu(char *dest, size_t destsize,
 						   const char *src, ssize_t srclen,
 						   pg_locale_t locale);
@@ -118,6 +121,25 @@ static int32_t u_strFoldCase_default(UChar *dest, int32_t destCapacity,
 									 const char *locale,
 									 UErrorCode *pErrorCode);
 
+static bool
+char_is_cased_icu(char ch, pg_locale_t locale)
+{
+	return IS_HIGHBIT_SET(ch) ||
+		(ch >= 'A' && ch <= 'Z') || (ch >= 'a' && ch <= 'z');
+}
+
+static pg_wchar
+toupper_icu(pg_wchar wc, pg_locale_t locale)
+{
+	return u_toupper(wc);
+}
+
+static pg_wchar
+tolower_icu(pg_wchar wc, pg_locale_t locale)
+{
+	return u_tolower(wc);
+}
+
 static const struct collate_methods collate_methods_icu = {
 	.strncoll = strncoll_icu,
 	.strnxfrm = strnxfrm_icu,
@@ -136,6 +158,78 @@ static const struct collate_methods collate_methods_icu_utf8 = {
 	.strxfrm_is_safe = true,
 };
 
+static bool
+wc_isdigit_icu(pg_wchar wc, pg_locale_t locale)
+{
+	return u_isdigit(wc);
+}
+
+static bool
+wc_isalpha_icu(pg_wchar wc, pg_locale_t locale)
+{
+	return u_isalpha(wc);
+}
+
+static bool
+wc_isalnum_icu(pg_wchar wc, pg_locale_t locale)
+{
+	return u_isalnum(wc);
+}
+
+static bool
+wc_isupper_icu(pg_wchar wc, pg_locale_t locale)
+{
+	return u_isupper(wc);
+}
+
+static bool
+wc_islower_icu(pg_wchar wc, pg_locale_t locale)
+{
+	return u_islower(wc);
+}
+
+static bool
+wc_isgraph_icu(pg_wchar wc, pg_locale_t locale)
+{
+	return u_isgraph(wc);
+}
+
+static bool
+wc_isprint_icu(pg_wchar wc, pg_locale_t locale)
+{
+	return u_isprint(wc);
+}
+
+static bool
+wc_ispunct_icu(pg_wchar wc, pg_locale_t locale)
+{
+	return u_ispunct(wc);
+}
+
+static bool
+wc_isspace_icu(pg_wchar wc, pg_locale_t locale)
+{
+	return u_isspace(wc);
+}
+
+static const struct ctype_methods ctype_methods_icu = {
+	.strlower = strlower_icu,
+	.strtitle = strtitle_icu,
+	.strupper = strupper_icu,
+	.strfold = strfold_icu,
+	.wc_isdigit = wc_isdigit_icu,
+	.wc_isalpha = wc_isalpha_icu,
+	.wc_isalnum = wc_isalnum_icu,
+	.wc_isupper = wc_isupper_icu,
+	.wc_islower = wc_islower_icu,
+	.wc_isgraph = wc_isgraph_icu,
+	.wc_isprint = wc_isprint_icu,
+	.wc_ispunct = wc_ispunct_icu,
+	.wc_isspace = wc_isspace_icu,
+	.char_is_cased = char_is_cased_icu,
+	.wc_toupper = toupper_icu,
+	.wc_tolower = tolower_icu,
+};
 #endif
 
 pg_locale_t
@@ -198,7 +292,6 @@ create_pg_locale_icu(Oid collid, MemoryContext context)
 	result = MemoryContextAllocZero(context, sizeof(struct pg_locale_struct));
 	result->info.icu.locale = MemoryContextStrdup(context, iculocstr);
 	result->info.icu.ucol = collator;
-	result->provider = COLLPROVIDER_ICU;
 	result->deterministic = deterministic;
 	result->collate_is_c = false;
 	result->ctype_is_c = false;
@@ -206,6 +299,7 @@ create_pg_locale_icu(Oid collid, MemoryContext context)
 		result->collate = &collate_methods_icu_utf8;
 	else
 		result->collate = &collate_methods_icu;
+	result->ctype = &ctype_methods_icu;
 
 	return result;
 #else
@@ -379,7 +473,7 @@ make_icu_collator(const char *iculocstr, const char *icurules)
 	}
 }
 
-size_t
+static size_t
 strlower_icu(char *dest, size_t destsize, const char *src, ssize_t srclen,
 			 pg_locale_t locale)
 {
@@ -399,7 +493,7 @@ strlower_icu(char *dest, size_t destsize, const char *src, ssize_t srclen,
 	return result_len;
 }
 
-size_t
+static size_t
 strtitle_icu(char *dest, size_t destsize, const char *src, ssize_t srclen,
 			 pg_locale_t locale)
 {
@@ -419,7 +513,7 @@ strtitle_icu(char *dest, size_t destsize, const char *src, ssize_t srclen,
 	return result_len;
 }
 
-size_t
+static size_t
 strupper_icu(char *dest, size_t destsize, const char *src, ssize_t srclen,
 			 pg_locale_t locale)
 {
@@ -439,7 +533,7 @@ strupper_icu(char *dest, size_t destsize, const char *src, ssize_t srclen,
 	return result_len;
 }
 
-size_t
+static size_t
 strfold_icu(char *dest, size_t destsize, const char *src, ssize_t srclen,
 			pg_locale_t locale)
 {
@@ -474,8 +568,6 @@ strncoll_icu_utf8(const char *arg1, ssize_t len1, const char *arg2, ssize_t len2
 	int			result;
 	UErrorCode	status;
 
-	Assert(locale->provider == COLLPROVIDER_ICU);
-
 	Assert(GetDatabaseEncoding() == PG_UTF8);
 
 	status = U_ZERO_ERROR;
@@ -503,8 +595,6 @@ strnxfrm_icu(char *dest, size_t destsize, const char *src, ssize_t srclen,
 	size_t		uchar_bsize;
 	Size		result_bsize;
 
-	Assert(locale->provider == COLLPROVIDER_ICU);
-
 	init_icu_converter();
 
 	ulen = uchar_length(icu_converter, src, srclen);
@@ -549,8 +639,6 @@ strnxfrm_prefix_icu_utf8(char *dest, size_t destsize,
 	uint32_t	state[2];
 	UErrorCode	status;
 
-	Assert(locale->provider == COLLPROVIDER_ICU);
-
 	Assert(GetDatabaseEncoding() == PG_UTF8);
 
 	uiter_setUTF8(&iter, src, srclen);
@@ -749,8 +837,6 @@ strncoll_icu(const char *arg1, ssize_t len1,
 			   *uchar2;
 	int			result;
 
-	Assert(locale->provider == COLLPROVIDER_ICU);
-
 	/* if encoding is UTF8, use more efficient strncoll_icu_utf8 */
 #ifdef HAVE_UCOL_STRCOLLUTF8
 	Assert(GetDatabaseEncoding() != PG_UTF8);
@@ -799,8 +885,6 @@ strnxfrm_prefix_icu(char *dest, size_t destsize,
 	size_t		uchar_bsize;
 	Size		result_bsize;
 
-	Assert(locale->provider == COLLPROVIDER_ICU);
-
 	/* if encoding is UTF8, use more efficient strnxfrm_prefix_icu_utf8 */
 	Assert(GetDatabaseEncoding() != PG_UTF8);
 
diff --git a/src/backend/utils/adt/pg_locale_libc.c b/src/backend/utils/adt/pg_locale_libc.c
index 199857e22dbec..8d88b53c37529 100644
--- a/src/backend/utils/adt/pg_locale_libc.c
+++ b/src/backend/utils/adt/pg_locale_libc.c
@@ -33,6 +33,46 @@
 #include <shlwapi.h>
 #endif
 
+/*
+ * For the libc provider, to provide as much functionality as possible on a
+ * variety of platforms without going so far as to implement everything from
+ * scratch, we use several implementation strategies depending on the
+ * situation:
+ *
+ * 1. In C/POSIX collations, we use hard-wired code.  We can't depend on
+ * the <ctype.h> functions since those will obey LC_CTYPE.  Note that these
+ * collations don't give a fig about multibyte characters.
+ *
+ * 2. When working in UTF8 encoding, we use the <wctype.h> functions.
+ * This assumes that every platform uses Unicode codepoints directly
+ * as the wchar_t representation of Unicode.  (XXX: ICU makes this assumption
+ * even for non-UTF8 encodings, which may be a problem.)  On some platforms
+ * wchar_t is only 16 bits wide, so we have to punt for codepoints > 0xFFFF.
+ *
+ * 3. In all other encodings, we use the <ctype.h> functions for pg_wchar
+ * values up to 255, and punt for values above that.  This is 100% correct
+ * only in single-byte encodings such as LATINn.  However, non-Unicode
+ * multibyte encodings are mostly Far Eastern character sets for which the
+ * properties being tested here aren't very relevant for higher code values
+ * anyway.  The difficulty with using the <wctype.h> functions with
+ * non-Unicode multibyte encodings is that we can have no certainty that
+ * the platform's wchar_t representation matches what we do in pg_wchar
+ * conversions.
+ *
+ * As a special case, in the "default" collation, (2) and (3) force ASCII
+ * letters to follow ASCII upcase/downcase rules, while in a non-default
+ * collation we just let the library functions do what they will.  The case
+ * where this matters is treatment of I/i in Turkish, and the behavior is
+ * meant to match the upper()/lower() SQL functions.
+ *
+ * We store the active collation setting in static variables.  In principle
+ * it could be passed down to here via the regex library's "struct vars" data
+ * structure; but that would require somewhat invasive changes in the regex
+ * library, and right now there's no real benefit to be gained from that.
+ *
+ * NB: the coding here assumes pg_wchar is an unsigned type.
+ */
+
 /*
  * Size of stack buffer to use for string transformations, used to avoid heap
  * allocations in typical cases. This should be large enough that most strings
@@ -43,13 +83,6 @@
 
 extern pg_locale_t create_pg_locale_libc(Oid collid, MemoryContext context);
 
-extern size_t strlower_libc(char *dst, size_t dstsize, const char *src,
-							ssize_t srclen, pg_locale_t locale);
-extern size_t strtitle_libc(char *dst, size_t dstsize, const char *src,
-							ssize_t srclen, pg_locale_t locale);
-extern size_t strupper_libc(char *dst, size_t dstsize, const char *src,
-							ssize_t srclen, pg_locale_t locale);
-
 static int	strncoll_libc(const char *arg1, ssize_t len1,
 						  const char *arg2, ssize_t len2,
 						  pg_locale_t locale);
@@ -85,6 +118,251 @@ static size_t strupper_libc_mb(char *dest, size_t destsize,
 							   const char *src, ssize_t srclen,
 							   pg_locale_t locale);
 
+static bool
+wc_isdigit_libc_sb(pg_wchar wc, pg_locale_t locale)
+{
+	return isdigit_l((unsigned char) wc, locale->info.lt);
+}
+
+static bool
+wc_isalpha_libc_sb(pg_wchar wc, pg_locale_t locale)
+{
+	return isalpha_l((unsigned char) wc, locale->info.lt);
+}
+
+static bool
+wc_isalnum_libc_sb(pg_wchar wc, pg_locale_t locale)
+{
+	return isalnum_l((unsigned char) wc, locale->info.lt);
+}
+
+static bool
+wc_isupper_libc_sb(pg_wchar wc, pg_locale_t locale)
+{
+	return isupper_l((unsigned char) wc, locale->info.lt);
+}
+
+static bool
+wc_islower_libc_sb(pg_wchar wc, pg_locale_t locale)
+{
+	return islower_l((unsigned char) wc, locale->info.lt);
+}
+
+static bool
+wc_isgraph_libc_sb(pg_wchar wc, pg_locale_t locale)
+{
+	return isgraph_l((unsigned char) wc, locale->info.lt);
+}
+
+static bool
+wc_isprint_libc_sb(pg_wchar wc, pg_locale_t locale)
+{
+	return isprint_l((unsigned char) wc, locale->info.lt);
+}
+
+static bool
+wc_ispunct_libc_sb(pg_wchar wc, pg_locale_t locale)
+{
+	return ispunct_l((unsigned char) wc, locale->info.lt);
+}
+
+static bool
+wc_isspace_libc_sb(pg_wchar wc, pg_locale_t locale)
+{
+	return isspace_l((unsigned char) wc, locale->info.lt);
+}
+
+static bool
+wc_isdigit_libc_mb(pg_wchar wc, pg_locale_t locale)
+{
+	return iswdigit_l((wint_t) wc, locale->info.lt);
+}
+
+static bool
+wc_isalpha_libc_mb(pg_wchar wc, pg_locale_t locale)
+{
+	return iswalpha_l((wint_t) wc, locale->info.lt);
+}
+
+static bool
+wc_isalnum_libc_mb(pg_wchar wc, pg_locale_t locale)
+{
+	return iswalnum_l((wint_t) wc, locale->info.lt);
+}
+
+static bool
+wc_isupper_libc_mb(pg_wchar wc, pg_locale_t locale)
+{
+	return iswupper_l((wint_t) wc, locale->info.lt);
+}
+
+static bool
+wc_islower_libc_mb(pg_wchar wc, pg_locale_t locale)
+{
+	return iswlower_l((wint_t) wc, locale->info.lt);
+}
+
+static bool
+wc_isgraph_libc_mb(pg_wchar wc, pg_locale_t locale)
+{
+	return iswgraph_l((wint_t) wc, locale->info.lt);
+}
+
+static bool
+wc_isprint_libc_mb(pg_wchar wc, pg_locale_t locale)
+{
+	return iswprint_l((wint_t) wc, locale->info.lt);
+}
+
+static bool
+wc_ispunct_libc_mb(pg_wchar wc, pg_locale_t locale)
+{
+	return iswpunct_l((wint_t) wc, locale->info.lt);
+}
+
+static bool
+wc_isspace_libc_mb(pg_wchar wc, pg_locale_t locale)
+{
+	return iswspace_l((wint_t) wc, locale->info.lt);
+}
+
+static char
+char_tolower_libc(unsigned char ch, pg_locale_t locale)
+{
+	Assert(pg_database_encoding_max_length() == 1);
+	return tolower_l(ch, locale->info.lt);
+}
+
+static bool
+char_is_cased_libc(char ch, pg_locale_t locale)
+{
+	bool		is_multibyte = pg_database_encoding_max_length() > 1;
+
+	if (is_multibyte && IS_HIGHBIT_SET(ch))
+		return true;
+	else
+		return isalpha_l((unsigned char) ch, locale->info.lt);
+}
+
+static pg_wchar
+toupper_libc_sb(pg_wchar wc, pg_locale_t locale)
+{
+	Assert(GetDatabaseEncoding() != PG_UTF8);
+
+	/* force C behavior for ASCII characters, per comments above */
+	if (locale->is_default && wc <= (pg_wchar) 127)
+		return pg_ascii_toupper((unsigned char) wc);
+	if (wc <= (pg_wchar) UCHAR_MAX)
+		return toupper_l((unsigned char) wc, locale->info.lt);
+	else
+		return wc;
+}
+
+static pg_wchar
+toupper_libc_mb(pg_wchar wc, pg_locale_t locale)
+{
+	Assert(GetDatabaseEncoding() == PG_UTF8);
+
+	/* force C behavior for ASCII characters, per comments above */
+	if (locale->is_default && wc <= (pg_wchar) 127)
+		return pg_ascii_toupper((unsigned char) wc);
+	if (sizeof(wchar_t) >= 4 || wc <= (pg_wchar) 0xFFFF)
+		return towupper_l((wint_t) wc, locale->info.lt);
+	else
+		return wc;
+}
+
+static pg_wchar
+tolower_libc_sb(pg_wchar wc, pg_locale_t locale)
+{
+	Assert(GetDatabaseEncoding() != PG_UTF8);
+
+	/* force C behavior for ASCII characters, per comments above */
+	if (locale->is_default && wc <= (pg_wchar) 127)
+		return pg_ascii_tolower((unsigned char) wc);
+	if (wc <= (pg_wchar) UCHAR_MAX)
+		return tolower_l((unsigned char) wc, locale->info.lt);
+	else
+		return wc;
+}
+
+static pg_wchar
+tolower_libc_mb(pg_wchar wc, pg_locale_t locale)
+{
+	Assert(GetDatabaseEncoding() == PG_UTF8);
+
+	/* force C behavior for ASCII characters, per comments above */
+	if (locale->is_default && wc <= (pg_wchar) 127)
+		return pg_ascii_tolower((unsigned char) wc);
+	if (sizeof(wchar_t) >= 4 || wc <= (pg_wchar) 0xFFFF)
+		return towlower_l((wint_t) wc, locale->info.lt);
+	else
+		return wc;
+}
+
+static const struct ctype_methods ctype_methods_libc_sb = {
+	.strlower = strlower_libc_sb,
+	.strtitle = strtitle_libc_sb,
+	.strupper = strupper_libc_sb,
+	.wc_isdigit = wc_isdigit_libc_sb,
+	.wc_isalpha = wc_isalpha_libc_sb,
+	.wc_isalnum = wc_isalnum_libc_sb,
+	.wc_isupper = wc_isupper_libc_sb,
+	.wc_islower = wc_islower_libc_sb,
+	.wc_isgraph = wc_isgraph_libc_sb,
+	.wc_isprint = wc_isprint_libc_sb,
+	.wc_ispunct = wc_ispunct_libc_sb,
+	.wc_isspace = wc_isspace_libc_sb,
+	.char_is_cased = char_is_cased_libc,
+	.char_tolower = char_tolower_libc,
+	.wc_toupper = toupper_libc_sb,
+	.wc_tolower = tolower_libc_sb,
+	.max_chr = UCHAR_MAX,
+};
+
+/*
+ * Non-UTF8 multibyte encodings use multibyte semantics for case mapping, but
+ * single-byte semantics for pattern matching.
+ */
+static const struct ctype_methods ctype_methods_libc_other_mb = {
+	.strlower = strlower_libc_mb,
+	.strtitle = strtitle_libc_mb,
+	.strupper = strupper_libc_mb,
+	.wc_isdigit = wc_isdigit_libc_sb,
+	.wc_isalpha = wc_isalpha_libc_sb,
+	.wc_isalnum = wc_isalnum_libc_sb,
+	.wc_isupper = wc_isupper_libc_sb,
+	.wc_islower = wc_islower_libc_sb,
+	.wc_isgraph = wc_isgraph_libc_sb,
+	.wc_isprint = wc_isprint_libc_sb,
+	.wc_ispunct = wc_ispunct_libc_sb,
+	.wc_isspace = wc_isspace_libc_sb,
+	.char_is_cased = char_is_cased_libc,
+	.char_tolower = char_tolower_libc,
+	.wc_toupper = toupper_libc_sb,
+	.wc_tolower = tolower_libc_sb,
+	.max_chr = UCHAR_MAX,
+};
+
+static const struct ctype_methods ctype_methods_libc_utf8 = {
+	.strlower = strlower_libc_mb,
+	.strtitle = strtitle_libc_mb,
+	.strupper = strupper_libc_mb,
+	.wc_isdigit = wc_isdigit_libc_mb,
+	.wc_isalpha = wc_isalpha_libc_mb,
+	.wc_isalnum = wc_isalnum_libc_mb,
+	.wc_isupper = wc_isupper_libc_mb,
+	.wc_islower = wc_islower_libc_mb,
+	.wc_isgraph = wc_isgraph_libc_mb,
+	.wc_isprint = wc_isprint_libc_mb,
+	.wc_ispunct = wc_ispunct_libc_mb,
+	.wc_isspace = wc_isspace_libc_mb,
+	.char_is_cased = char_is_cased_libc,
+	.char_tolower = char_tolower_libc,
+	.wc_toupper = toupper_libc_mb,
+	.wc_tolower = tolower_libc_mb,
+};
+
 static const struct collate_methods collate_methods_libc = {
 	.strncoll = strncoll_libc,
 	.strnxfrm = strnxfrm_libc,
@@ -119,36 +397,6 @@ static const struct collate_methods collate_methods_libc_win32_utf8 = {
 };
 #endif
 
-size_t
-strlower_libc(char *dst, size_t dstsize, const char *src,
-			  ssize_t srclen, pg_locale_t locale)
-{
-	if (pg_database_encoding_max_length() > 1)
-		return strlower_libc_mb(dst, dstsize, src, srclen, locale);
-	else
-		return strlower_libc_sb(dst, dstsize, src, srclen, locale);
-}
-
-size_t
-strtitle_libc(char *dst, size_t dstsize, const char *src,
-			  ssize_t srclen, pg_locale_t locale)
-{
-	if (pg_database_encoding_max_length() > 1)
-		return strtitle_libc_mb(dst, dstsize, src, srclen, locale);
-	else
-		return strtitle_libc_sb(dst, dstsize, src, srclen, locale);
-}
-
-size_t
-strupper_libc(char *dst, size_t dstsize, const char *src,
-			  ssize_t srclen, pg_locale_t locale)
-{
-	if (pg_database_encoding_max_length() > 1)
-		return strupper_libc_mb(dst, dstsize, src, srclen, locale);
-	else
-		return strupper_libc_sb(dst, dstsize, src, srclen, locale);
-}
-
 static size_t
 strlower_libc_sb(char *dest, size_t destsize, const char *src, ssize_t srclen,
 				 pg_locale_t locale)
@@ -209,7 +457,7 @@ strlower_libc_mb(char *dest, size_t destsize, const char *src, ssize_t srclen,
 	/* Output workspace cannot have more codes than input bytes */
 	workspace = (wchar_t *) palloc((srclen + 1) * sizeof(wchar_t));
 
-	char2wchar(workspace, srclen + 1, src, srclen, locale);
+	char2wchar(workspace, srclen + 1, src, srclen, loc);
 
 	for (curr_char = 0; workspace[curr_char] != 0; curr_char++)
 		workspace[curr_char] = towlower_l(workspace[curr_char], loc);
@@ -220,7 +468,7 @@ strlower_libc_mb(char *dest, size_t destsize, const char *src, ssize_t srclen,
 	max_size = curr_char * pg_database_encoding_max_length();
 	result = palloc(max_size + 1);
 
-	result_size = wchar2char(result, workspace, max_size + 1, locale);
+	result_size = wchar2char(result, workspace, max_size + 1, loc);
 
 	if (result_size + 1 > destsize)
 		return result_size;
@@ -304,7 +552,7 @@ strtitle_libc_mb(char *dest, size_t destsize, const char *src, ssize_t srclen,
 	/* Output workspace cannot have more codes than input bytes */
 	workspace = (wchar_t *) palloc((srclen + 1) * sizeof(wchar_t));
 
-	char2wchar(workspace, srclen + 1, src, srclen, locale);
+	char2wchar(workspace, srclen + 1, src, srclen, loc);
 
 	for (curr_char = 0; workspace[curr_char] != 0; curr_char++)
 	{
@@ -321,7 +569,7 @@ strtitle_libc_mb(char *dest, size_t destsize, const char *src, ssize_t srclen,
 	max_size = curr_char * pg_database_encoding_max_length();
 	result = palloc(max_size + 1);
 
-	result_size = wchar2char(result, workspace, max_size + 1, locale);
+	result_size = wchar2char(result, workspace, max_size + 1, loc);
 
 	if (result_size + 1 > destsize)
 		return result_size;
@@ -392,7 +640,7 @@ strupper_libc_mb(char *dest, size_t destsize, const char *src, ssize_t srclen,
 	/* Output workspace cannot have more codes than input bytes */
 	workspace = (wchar_t *) palloc((srclen + 1) * sizeof(wchar_t));
 
-	char2wchar(workspace, srclen + 1, src, srclen, locale);
+	char2wchar(workspace, srclen + 1, src, srclen, loc);
 
 	for (curr_char = 0; workspace[curr_char] != 0; curr_char++)
 		workspace[curr_char] = towupper_l(workspace[curr_char], loc);
@@ -403,7 +651,7 @@ strupper_libc_mb(char *dest, size_t destsize, const char *src, ssize_t srclen,
 	max_size = curr_char * pg_database_encoding_max_length();
 	result = palloc(max_size + 1);
 
-	result_size = wchar2char(result, workspace, max_size + 1, locale);
+	result_size = wchar2char(result, workspace, max_size + 1, loc);
 
 	if (result_size + 1 > destsize)
 		return result_size;
@@ -465,7 +713,6 @@ create_pg_locale_libc(Oid collid, MemoryContext context)
 	loc = make_libc_collator(collate, ctype);
 
 	result = MemoryContextAllocZero(context, sizeof(struct pg_locale_struct));
-	result->provider = COLLPROVIDER_LIBC;
 	result->deterministic = true;
 	result->collate_is_c = (strcmp(collate, "C") == 0) ||
 		(strcmp(collate, "POSIX") == 0);
@@ -481,6 +728,15 @@ create_pg_locale_libc(Oid collid, MemoryContext context)
 #endif
 			result->collate = &collate_methods_libc;
 	}
+	if (!result->ctype_is_c)
+	{
+		if (GetDatabaseEncoding() == PG_UTF8)
+			result->ctype = &ctype_methods_libc_utf8;
+		else if (pg_database_encoding_max_length() > 1)
+			result->ctype = &ctype_methods_libc_other_mb;
+		else
+			result->ctype = &ctype_methods_libc_sb;
+	}
 
 	return result;
 }
@@ -576,8 +832,6 @@ strncoll_libc(const char *arg1, ssize_t len1, const char *arg2, ssize_t len2,
 	const char *arg2n;
 	int			result;
 
-	Assert(locale->provider == COLLPROVIDER_LIBC);
-
 	if (bufsize1 + bufsize2 > TEXTBUFLEN)
 		buf = palloc(bufsize1 + bufsize2);
 
@@ -632,8 +886,6 @@ strnxfrm_libc(char *dest, size_t destsize, const char *src, ssize_t srclen,
 	size_t		bufsize = srclen + 1;
 	size_t		result;
 
-	Assert(locale->provider == COLLPROVIDER_LIBC);
-
 	if (srclen == -1)
 		return strxfrm_l(dest, src, destsize, locale->info.lt);
 
@@ -742,7 +994,6 @@ strncoll_libc_win32_utf8(const char *arg1, ssize_t len1, const char *arg2,
 	int			r;
 	int			result;
 
-	Assert(locale->provider == COLLPROVIDER_LIBC);
 	Assert(GetDatabaseEncoding() == PG_UTF8);
 
 	if (len1 == -1)
@@ -879,7 +1130,7 @@ wcstombs_l(char *dest, const wchar_t *src, size_t n, locale_t loc)
  * zero-terminated.  The output will be zero-terminated iff there is room.
  */
 size_t
-wchar2char(char *to, const wchar_t *from, size_t tolen, pg_locale_t locale)
+wchar2char(char *to, const wchar_t *from, size_t tolen, locale_t loc)
 {
 	size_t		result;
 
@@ -909,7 +1160,7 @@ wchar2char(char *to, const wchar_t *from, size_t tolen, pg_locale_t locale)
 	}
 	else
 #endif							/* WIN32 */
-	if (locale == (pg_locale_t) 0)
+	if (loc == (locale_t) 0)
 	{
 		/* Use wcstombs directly for the default locale */
 		result = wcstombs(to, from, tolen);
@@ -917,7 +1168,7 @@ wchar2char(char *to, const wchar_t *from, size_t tolen, pg_locale_t locale)
 	else
 	{
 		/* Use wcstombs_l for nondefault locales */
-		result = wcstombs_l(to, from, tolen, locale->info.lt);
+		result = wcstombs_l(to, from, tolen, loc);
 	}
 
 	return result;
@@ -934,7 +1185,7 @@ wchar2char(char *to, const wchar_t *from, size_t tolen, pg_locale_t locale)
  */
 size_t
 char2wchar(wchar_t *to, size_t tolen, const char *from, size_t fromlen,
-		   pg_locale_t locale)
+		   locale_t loc)
 {
 	size_t		result;
 
@@ -969,7 +1220,7 @@ char2wchar(wchar_t *to, size_t tolen, const char *from, size_t fromlen,
 		/* mbstowcs requires ending '\0' */
 		char	   *str = pnstrdup(from, fromlen);
 
-		if (locale == (pg_locale_t) 0)
+		if (loc == (locale_t) 0)
 		{
 			/* Use mbstowcs directly for the default locale */
 			result = mbstowcs(to, str, tolen);
@@ -977,7 +1228,7 @@ char2wchar(wchar_t *to, size_t tolen, const char *from, size_t fromlen,
 		else
 		{
 			/* Use mbstowcs_l for nondefault locales */
-			result = mbstowcs_l(to, str, tolen, locale->info.lt);
+			result = mbstowcs_l(to, str, tolen, loc);
 		}
 
 		pfree(str);
diff --git a/src/backend/utils/adt/pg_lsn.c b/src/backend/utils/adt/pg_lsn.c
index 16311590a14a0..12de2446f5b69 100644
--- a/src/backend/utils/adt/pg_lsn.c
+++ b/src/backend/utils/adt/pg_lsn.c
@@ -83,7 +83,7 @@ pg_lsn_out(PG_FUNCTION_ARGS)
 	char		buf[MAXPG_LSNLEN + 1];
 	char	   *result;
 
-	snprintf(buf, sizeof buf, "%X/%X", LSN_FORMAT_ARGS(lsn));
+	snprintf(buf, sizeof buf, "%X/%08X", LSN_FORMAT_ARGS(lsn));
 	result = pstrdup(buf);
 	PG_RETURN_CSTRING(result);
 }
diff --git a/src/backend/utils/adt/pg_upgrade_support.c b/src/backend/utils/adt/pg_upgrade_support.c
index d44f8c262baa2..a4f8b4faa90dc 100644
--- a/src/backend/utils/adt/pg_upgrade_support.c
+++ b/src/backend/utils/adt/pg_upgrade_support.c
@@ -21,6 +21,7 @@
 #include "commands/extension.h"
 #include "miscadmin.h"
 #include "replication/logical.h"
+#include "replication/logicallauncher.h"
 #include "replication/origin.h"
 #include "replication/worker_internal.h"
 #include "storage/lmgr.h"
@@ -410,3 +411,21 @@ binary_upgrade_replorigin_advance(PG_FUNCTION_ARGS)
 
 	PG_RETURN_VOID();
 }
+
+/*
+ * binary_upgrade_create_conflict_detection_slot
+ *
+ * Create a replication slot to retain information necessary for conflict
+ * detection such as dead tuples, commit timestamps, and origins.
+ */
+Datum
+binary_upgrade_create_conflict_detection_slot(PG_FUNCTION_ARGS)
+{
+	CHECK_IS_BINARY_UPGRADE;
+
+	CreateConflictDetectionSlot();
+
+	ReplicationSlotRelease();
+
+	PG_RETURN_VOID();
+}
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 1c12ddbae493c..c756c2bebaaa0 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -2171,7 +2171,7 @@ pg_stat_get_replication_slot(PG_FUNCTION_ARGS)
 Datum
 pg_stat_get_subscription_stats(PG_FUNCTION_ARGS)
 {
-#define PG_STAT_GET_SUBSCRIPTION_STATS_COLS	11
+#define PG_STAT_GET_SUBSCRIPTION_STATS_COLS	12
 	Oid			subid = PG_GETARG_OID(0);
 	TupleDesc	tupdesc;
 	Datum		values[PG_STAT_GET_SUBSCRIPTION_STATS_COLS] = {0};
@@ -2197,15 +2197,17 @@ pg_stat_get_subscription_stats(PG_FUNCTION_ARGS)
 					   INT8OID, -1, 0);
 	TupleDescInitEntry(tupdesc, (AttrNumber) 6, "confl_update_exists",
 					   INT8OID, -1, 0);
-	TupleDescInitEntry(tupdesc, (AttrNumber) 7, "confl_update_missing",
+	TupleDescInitEntry(tupdesc, (AttrNumber) 7, "confl_update_deleted",
 					   INT8OID, -1, 0);
-	TupleDescInitEntry(tupdesc, (AttrNumber) 8, "confl_delete_origin_differs",
+	TupleDescInitEntry(tupdesc, (AttrNumber) 8, "confl_update_missing",
 					   INT8OID, -1, 0);
-	TupleDescInitEntry(tupdesc, (AttrNumber) 9, "confl_delete_missing",
+	TupleDescInitEntry(tupdesc, (AttrNumber) 9, "confl_delete_origin_differs",
 					   INT8OID, -1, 0);
-	TupleDescInitEntry(tupdesc, (AttrNumber) 10, "confl_multiple_unique_conflicts",
+	TupleDescInitEntry(tupdesc, (AttrNumber) 10, "confl_delete_missing",
 					   INT8OID, -1, 0);
-	TupleDescInitEntry(tupdesc, (AttrNumber) 11, "stats_reset",
+	TupleDescInitEntry(tupdesc, (AttrNumber) 11, "confl_multiple_unique_conflicts",
+					   INT8OID, -1, 0);
+	TupleDescInitEntry(tupdesc, (AttrNumber) 12, "stats_reset",
 					   TIMESTAMPTZOID, -1, 0);
 	BlessTupleDesc(tupdesc);
 
diff --git a/src/backend/utils/adt/rangetypes.c b/src/backend/utils/adt/rangetypes.c
index 66cc0acf4a712..c83b239b3bb28 100644
--- a/src/backend/utils/adt/rangetypes.c
+++ b/src/backend/utils/adt/rangetypes.c
@@ -285,8 +285,7 @@ range_send(PG_FUNCTION_ARGS)
 
 	if (RANGE_HAS_LBOUND(flags))
 	{
-		Datum		bound = PointerGetDatum(SendFunctionCall(&cache->typioproc,
-															 lower.val));
+		bytea	   *bound = SendFunctionCall(&cache->typioproc, lower.val);
 		uint32		bound_len = VARSIZE(bound) - VARHDRSZ;
 		char	   *bound_data = VARDATA(bound);
 
@@ -296,8 +295,7 @@ range_send(PG_FUNCTION_ARGS)
 
 	if (RANGE_HAS_UBOUND(flags))
 	{
-		Datum		bound = PointerGetDatum(SendFunctionCall(&cache->typioproc,
-															 upper.val));
+		bytea	   *bound = SendFunctionCall(&cache->typioproc, upper.val);
 		uint32		bound_len = VARSIZE(bound) - VARHDRSZ;
 		char	   *bound_data = VARDATA(bound);
 
@@ -1444,7 +1442,7 @@ hash_range(PG_FUNCTION_ARGS)
 		upper_hash = 0;
 
 	/* Merge hashes of flags and bounds */
-	result = hash_uint32((uint32) flags);
+	result = hash_bytes_uint32((uint32) flags);
 	result ^= lower_hash;
 	result = pg_rotate_left32(result, 1);
 	result ^= upper_hash;
diff --git a/src/backend/utils/adt/regproc.c b/src/backend/utils/adt/regproc.c
index 5ee608a2b3921..b8bbe95e82eb8 100644
--- a/src/backend/utils/adt/regproc.c
+++ b/src/backend/utils/adt/regproc.c
@@ -30,6 +30,7 @@
 #include "catalog/pg_ts_config.h"
 #include "catalog/pg_ts_dict.h"
 #include "catalog/pg_type.h"
+#include "commands/dbcommands.h"
 #include "lib/stringinfo.h"
 #include "mb/pg_wchar.h"
 #include "miscadmin.h"
@@ -1763,6 +1764,123 @@ regnamespacesend(PG_FUNCTION_ARGS)
 	return oidsend(fcinfo);
 }
 
+/*
+ * regdatabasein - converts database name to database OID
+ *
+ * We also accept a numeric OID, for symmetry with the output routine.
+ *
+ * '-' signifies unknown (OID 0).  In all other cases, the input must
+ * match an existing pg_database entry.
+ */
+Datum
+regdatabasein(PG_FUNCTION_ARGS)
+{
+	char	   *db_name_or_oid = PG_GETARG_CSTRING(0);
+	Node	   *escontext = fcinfo->context;
+	Oid			result;
+	List	   *names;
+
+	/* Handle "-" or numeric OID */
+	if (parseDashOrOid(db_name_or_oid, &result, escontext))
+		PG_RETURN_OID(result);
+
+	/* The rest of this wouldn't work in bootstrap mode */
+	if (IsBootstrapProcessingMode())
+		elog(ERROR, "regdatabase values must be OIDs in bootstrap mode");
+
+	/* Normal case: see if the name matches any pg_database entry. */
+	names = stringToQualifiedNameList(db_name_or_oid, escontext);
+	if (names == NIL)
+		PG_RETURN_NULL();
+
+	if (list_length(names) != 1)
+		ereturn(escontext, (Datum) 0,
+				(errcode(ERRCODE_INVALID_NAME),
+				 errmsg("invalid name syntax")));
+
+	result = get_database_oid(strVal(linitial(names)), true);
+
+	if (!OidIsValid(result))
+		ereturn(escontext, (Datum) 0,
+				(errcode(ERRCODE_UNDEFINED_OBJECT),
+				 errmsg("database \"%s\" does not exist",
+						strVal(linitial(names)))));
+
+	PG_RETURN_OID(result);
+}
+
+/*
+ * to_regdatabase - converts database name to database OID
+ *
+ * If the name is not found, we return NULL.
+ */
+Datum
+to_regdatabase(PG_FUNCTION_ARGS)
+{
+	char	   *db_name = text_to_cstring(PG_GETARG_TEXT_PP(0));
+	Datum		result;
+	ErrorSaveContext escontext = {T_ErrorSaveContext};
+
+	if (!DirectInputFunctionCallSafe(regdatabasein, db_name,
+									 InvalidOid, -1,
+									 (Node *) &escontext,
+									 &result))
+		PG_RETURN_NULL();
+	PG_RETURN_DATUM(result);
+}
+
+/*
+ * regdatabaseout - converts database OID to database name
+ */
+Datum
+regdatabaseout(PG_FUNCTION_ARGS)
+{
+	Oid			dboid = PG_GETARG_OID(0);
+	char	   *result;
+
+	if (dboid == InvalidOid)
+	{
+		result = pstrdup("-");
+		PG_RETURN_CSTRING(result);
+	}
+
+	result = get_database_name(dboid);
+
+	if (result)
+	{
+		/* pstrdup is not really necessary, but it avoids a compiler warning */
+		result = pstrdup(quote_identifier(result));
+	}
+	else
+	{
+		/* If OID doesn't match any database, return it numerically */
+		result = (char *) palloc(NAMEDATALEN);
+		snprintf(result, NAMEDATALEN, "%u", dboid);
+	}
+
+	PG_RETURN_CSTRING(result);
+}
+
+/*
+ * regdatabaserecv - converts external binary format to regdatabase
+ */
+Datum
+regdatabaserecv(PG_FUNCTION_ARGS)
+{
+	/* Exactly the same as oidrecv, so share code */
+	return oidrecv(fcinfo);
+}
+
+/*
+ * regdatabasesend - converts regdatabase to binary format
+ */
+Datum
+regdatabasesend(PG_FUNCTION_ARGS)
+{
+	/* Exactly the same as oidsend, so share code */
+	return oidsend(fcinfo);
+}
+
 /*
  * text_regclass: convert text to regclass
  *
diff --git a/src/backend/utils/adt/ri_triggers.c b/src/backend/utils/adt/ri_triggers.c
index 6239900fa2892..059fc5ebf601a 100644
--- a/src/backend/utils/adt/ri_triggers.c
+++ b/src/backend/utils/adt/ri_triggers.c
@@ -30,7 +30,6 @@
 #include "access/xact.h"
 #include "catalog/pg_collation.h"
 #include "catalog/pg_constraint.h"
-#include "catalog/pg_proc.h"
 #include "commands/trigger.h"
 #include "executor/executor.h"
 #include "executor/spi.h"
@@ -46,7 +45,6 @@
 #include "utils/inval.h"
 #include "utils/lsyscache.h"
 #include "utils/memutils.h"
-#include "utils/rangetypes.h"
 #include "utils/rel.h"
 #include "utils/rls.h"
 #include "utils/ruleutils.h"
diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c
index a96b1b9c0bc69..17fbfa9b41063 100644
--- a/src/backend/utils/adt/selfuncs.c
+++ b/src/backend/utils/adt/selfuncs.c
@@ -103,7 +103,6 @@
 #include "access/table.h"
 #include "access/tableam.h"
 #include "access/visibilitymap.h"
-#include "catalog/pg_am.h"
 #include "catalog/pg_collation.h"
 #include "catalog/pg_operator.h"
 #include "catalog/pg_statistic.h"
@@ -3799,18 +3798,25 @@ estimate_multivariate_bucketsize(PlannerInfo *root, RelOptInfo *inner,
 								 List *hashclauses,
 								 Selectivity *innerbucketsize)
 {
-	List	   *clauses = list_copy(hashclauses);
-	List	   *otherclauses = NIL;
-	double		ndistinct = 1.0;
+	List	   *clauses;
+	List	   *otherclauses;
+	double		ndistinct;
 
 	if (list_length(hashclauses) <= 1)
-
+	{
 		/*
 		 * Nothing to do for a single clause.  Could we employ univariate
 		 * extended stat here?
 		 */
 		return hashclauses;
+	}
 
+	/* "clauses" is the list of hashclauses we've not dealt with yet */
+	clauses = list_copy(hashclauses);
+	/* "otherclauses" holds clauses we are going to return to caller */
+	otherclauses = NIL;
+	/* current estimate of ndistinct */
+	ndistinct = 1.0;
 	while (clauses != NIL)
 	{
 		ListCell   *lc;
@@ -3875,12 +3881,13 @@ estimate_multivariate_bucketsize(PlannerInfo *root, RelOptInfo *inner,
 					group_rel = root->simple_rel_array[relid];
 				}
 				else if (group_relid != relid)
-
+				{
 					/*
 					 * Being in the group forming state we don't need other
 					 * clauses.
 					 */
 					continue;
+				}
 
 				/*
 				 * We're going to add the new clause to the varinfos list.  We
@@ -4620,6 +4627,7 @@ convert_to_scalar(Datum value, Oid valuetypid, Oid collid, double *scaledvalue,
 		case REGDICTIONARYOID:
 		case REGROLEOID:
 		case REGNAMESPACEOID:
+		case REGDATABASEOID:
 			*scaledvalue = convert_numeric_to_scalar(value, valuetypid,
 													 &failure);
 			*scaledlobound = convert_numeric_to_scalar(lobound, boundstypid,
@@ -4752,6 +4760,7 @@ convert_numeric_to_scalar(Datum value, Oid typid, bool *failure)
 		case REGDICTIONARYOID:
 		case REGROLEOID:
 		case REGNAMESPACEOID:
+		case REGDATABASEOID:
 			/* we can treat OIDs as integers... */
 			return (double) DatumGetObjectId(value);
 	}
diff --git a/src/backend/utils/adt/tid.c b/src/backend/utils/adt/tid.c
index 1b0df1117171a..39dab3e42df58 100644
--- a/src/backend/utils/adt/tid.c
+++ b/src/backend/utils/adt/tid.c
@@ -84,7 +84,7 @@ tidin(PG_FUNCTION_ARGS)
 	/*
 	 * Cope with possibility that unsigned long is wider than BlockNumber, in
 	 * which case strtoul will not raise an error for some values that are out
-	 * of the range of BlockNumber.  (See similar code in oidin().)
+	 * of the range of BlockNumber.  (See similar code in uint32in_subr().)
 	 */
 #if SIZEOF_LONG > 4
 	if (cvt != (unsigned long) blockNumber &&
diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c
index 347089b762646..25cff56c3d07e 100644
--- a/src/backend/utils/adt/timestamp.c
+++ b/src/backend/utils/adt/timestamp.c
@@ -5312,10 +5312,10 @@ isoweekdate2date(int isoweek, int wday, int *year, int *mon, int *mday)
 int
 date2isoweek(int year, int mon, int mday)
 {
-	float8		result;
 	int			day0,
 				day4,
-				dayn;
+				dayn,
+				week;
 
 	/* current day */
 	dayn = date2j(year, mon, mday);
@@ -5338,13 +5338,13 @@ date2isoweek(int year, int mon, int mday)
 		day0 = j2day(day4 - 1);
 	}
 
-	result = (dayn - (day4 - day0)) / 7 + 1;
+	week = (dayn - (day4 - day0)) / 7 + 1;
 
 	/*
 	 * Sometimes the last few days in a year will fall into the first week of
 	 * the next year, so check for this.
 	 */
-	if (result >= 52)
+	if (week >= 52)
 	{
 		day4 = date2j(year + 1, 1, 4);
 
@@ -5352,10 +5352,10 @@ date2isoweek(int year, int mon, int mday)
 		day0 = j2day(day4 - 1);
 
 		if (dayn >= day4 - day0)
-			result = (dayn - (day4 - day0)) / 7 + 1;
+			week = (dayn - (day4 - day0)) / 7 + 1;
 	}
 
-	return (int) result;
+	return week;
 }
 
 
@@ -5367,10 +5367,10 @@ date2isoweek(int year, int mon, int mday)
 int
 date2isoyear(int year, int mon, int mday)
 {
-	float8		result;
 	int			day0,
 				day4,
-				dayn;
+				dayn,
+				week;
 
 	/* current day */
 	dayn = date2j(year, mon, mday);
@@ -5395,13 +5395,13 @@ date2isoyear(int year, int mon, int mday)
 		year--;
 	}
 
-	result = (dayn - (day4 - day0)) / 7 + 1;
+	week = (dayn - (day4 - day0)) / 7 + 1;
 
 	/*
 	 * Sometimes the last few days in a year will fall into the first week of
 	 * the next year, so check for this.
 	 */
-	if (result >= 52)
+	if (week >= 52)
 	{
 		day4 = date2j(year + 1, 1, 4);
 
@@ -6477,7 +6477,7 @@ timestamp2timestamptz_opt_overflow(Timestamp timestamp, int *overflow)
 	if (TIMESTAMP_NOT_FINITE(timestamp))
 		return timestamp;
 
-	/* We don't expect this to fail, but check it pro forma */
+	/* timestamp2tm should not fail on valid timestamps, but cope */
 	if (timestamp2tm(timestamp, NULL, tm, &fsec, NULL, NULL) == 0)
 	{
 		tz = DetermineTimeZoneOffset(tm, session_timezone);
@@ -6485,23 +6485,22 @@ timestamp2timestamptz_opt_overflow(Timestamp timestamp, int *overflow)
 		result = dt2local(timestamp, -tz);
 
 		if (IS_VALID_TIMESTAMP(result))
-		{
 			return result;
+	}
+
+	if (overflow)
+	{
+		if (timestamp < 0)
+		{
+			*overflow = -1;
+			TIMESTAMP_NOBEGIN(result);
 		}
-		else if (overflow)
+		else
 		{
-			if (result < MIN_TIMESTAMP)
-			{
-				*overflow = -1;
-				TIMESTAMP_NOBEGIN(result);
-			}
-			else
-			{
-				*overflow = 1;
-				TIMESTAMP_NOEND(result);
-			}
-			return result;
+			*overflow = 1;
+			TIMESTAMP_NOEND(result);
 		}
+		return result;
 	}
 
 	ereport(ERROR,
@@ -6531,8 +6530,27 @@ timestamptz_timestamp(PG_FUNCTION_ARGS)
 	PG_RETURN_TIMESTAMP(timestamptz2timestamp(timestamp));
 }
 
+/*
+ * Convert timestamptz to timestamp, throwing error for overflow.
+ */
 static Timestamp
 timestamptz2timestamp(TimestampTz timestamp)
+{
+	return timestamptz2timestamp_opt_overflow(timestamp, NULL);
+}
+
+/*
+ * Convert timestamp with time zone to timestamp.
+ *
+ * On successful conversion, *overflow is set to zero if it's not NULL.
+ *
+ * If the timestamptz is finite but out of the valid range for timestamp, then:
+ * if overflow is NULL, we throw an out-of-range error.
+ * if overflow is not NULL, we store +1 or -1 there to indicate the sign
+ * of the overflow, and return the appropriate timestamp infinity.
+ */
+Timestamp
+timestamptz2timestamp_opt_overflow(TimestampTz timestamp, int *overflow)
 {
 	Timestamp	result;
 	struct pg_tm tt,
@@ -6540,18 +6558,53 @@ timestamptz2timestamp(TimestampTz timestamp)
 	fsec_t		fsec;
 	int			tz;
 
+	if (overflow)
+		*overflow = 0;
+
 	if (TIMESTAMP_NOT_FINITE(timestamp))
 		result = timestamp;
 	else
 	{
 		if (timestamp2tm(timestamp, &tz, tm, &fsec, NULL, NULL) != 0)
+		{
+			if (overflow)
+			{
+				if (timestamp < 0)
+				{
+					*overflow = -1;
+					TIMESTAMP_NOBEGIN(result);
+				}
+				else
+				{
+					*overflow = 1;
+					TIMESTAMP_NOEND(result);
+				}
+				return result;
+			}
 			ereport(ERROR,
 					(errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
 					 errmsg("timestamp out of range")));
+		}
 		if (tm2timestamp(tm, fsec, NULL, &result) != 0)
+		{
+			if (overflow)
+			{
+				if (timestamp < 0)
+				{
+					*overflow = -1;
+					TIMESTAMP_NOBEGIN(result);
+				}
+				else
+				{
+					*overflow = 1;
+					TIMESTAMP_NOEND(result);
+				}
+				return result;
+			}
 			ereport(ERROR,
 					(errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
 					 errmsg("timestamp out of range")));
+		}
 	}
 	return result;
 }
diff --git a/src/backend/utils/adt/tsvector_op.c b/src/backend/utils/adt/tsvector_op.c
index 1fa1275ca63b2..0625da9532f6c 100644
--- a/src/backend/utils/adt/tsvector_op.c
+++ b/src/backend/utils/adt/tsvector_op.c
@@ -329,8 +329,8 @@ tsvector_setweight_by_filter(PG_FUNCTION_ARGS)
 		if (nulls[i])
 			continue;
 
-		lex = VARDATA(dlexemes[i]);
-		lex_len = VARSIZE(dlexemes[i]) - VARHDRSZ;
+		lex = VARDATA(DatumGetPointer(dlexemes[i]));
+		lex_len = VARSIZE(DatumGetPointer(dlexemes[i])) - VARHDRSZ;
 		lex_pos = tsvector_bsearch(tsout, lex, lex_len);
 
 		if (lex_pos >= 0 && (j = POSDATALEN(tsout, entry + lex_pos)) != 0)
@@ -443,10 +443,10 @@ compare_text_lexemes(const void *va, const void *vb)
 {
 	Datum		a = *((const Datum *) va);
 	Datum		b = *((const Datum *) vb);
-	char	   *alex = VARDATA_ANY(a);
-	int			alex_len = VARSIZE_ANY_EXHDR(a);
-	char	   *blex = VARDATA_ANY(b);
-	int			blex_len = VARSIZE_ANY_EXHDR(b);
+	char	   *alex = VARDATA_ANY(DatumGetPointer(a));
+	int			alex_len = VARSIZE_ANY_EXHDR(DatumGetPointer(a));
+	char	   *blex = VARDATA_ANY(DatumGetPointer(b));
+	int			blex_len = VARSIZE_ANY_EXHDR(DatumGetPointer(b));
 
 	return tsCompareString(alex, alex_len, blex, blex_len, false);
 }
@@ -605,8 +605,8 @@ tsvector_delete_arr(PG_FUNCTION_ARGS)
 		if (nulls[i])
 			continue;
 
-		lex = VARDATA(dlexemes[i]);
-		lex_len = VARSIZE(dlexemes[i]) - VARHDRSZ;
+		lex = VARDATA(DatumGetPointer(dlexemes[i]));
+		lex_len = VARSIZE(DatumGetPointer(dlexemes[i])) - VARHDRSZ;
 		lex_pos = tsvector_bsearch(tsin, lex, lex_len);
 
 		if (lex_pos >= 0)
@@ -770,7 +770,7 @@ array_to_tsvector(PG_FUNCTION_ARGS)
 					(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
 					 errmsg("lexeme array may not contain nulls")));
 
-		if (VARSIZE(dlexemes[i]) - VARHDRSZ == 0)
+		if (VARSIZE(DatumGetPointer(dlexemes[i])) - VARHDRSZ == 0)
 			ereport(ERROR,
 					(errcode(ERRCODE_ZERO_LENGTH_CHARACTER_STRING),
 					 errmsg("lexeme array may not contain empty strings")));
@@ -786,7 +786,7 @@ array_to_tsvector(PG_FUNCTION_ARGS)
 
 	/* Calculate space needed for surviving lexemes. */
 	for (i = 0; i < nitems; i++)
-		datalen += VARSIZE(dlexemes[i]) - VARHDRSZ;
+		datalen += VARSIZE(DatumGetPointer(dlexemes[i])) - VARHDRSZ;
 	tslen = CALCDATASIZE(nitems, datalen);
 
 	/* Allocate and fill tsvector. */
@@ -798,8 +798,8 @@ array_to_tsvector(PG_FUNCTION_ARGS)
 	cur = STRPTR(tsout);
 	for (i = 0; i < nitems; i++)
 	{
-		char	   *lex = VARDATA(dlexemes[i]);
-		int			lex_len = VARSIZE(dlexemes[i]) - VARHDRSZ;
+		char	   *lex = VARDATA(DatumGetPointer(dlexemes[i]));
+		int			lex_len = VARSIZE(DatumGetPointer(dlexemes[i])) - VARHDRSZ;
 
 		memcpy(cur, lex, lex_len);
 		arrout[i].haspos = 0;
diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c
index 3e4d5568bde89..ffae8c23abfaf 100644
--- a/src/backend/utils/adt/varlena.c
+++ b/src/backend/utils/adt/varlena.c
@@ -35,7 +35,6 @@
 #include "port/pg_bswap.h"
 #include "regex/regex.h"
 #include "utils/builtins.h"
-#include "utils/bytea.h"
 #include "utils/guc.h"
 #include "utils/lsyscache.h"
 #include "utils/memutils.h"
@@ -43,10 +42,6 @@
 #include "utils/sortsupport.h"
 #include "utils/varlena.h"
 
-
-/* GUC variable */
-int			bytea_output = BYTEA_OUTPUT_HEX;
-
 typedef struct varlena VarString;
 
 /*
@@ -148,12 +143,6 @@ static int	text_position_get_match_pos(TextPositionState *state);
 static void text_position_cleanup(TextPositionState *state);
 static void check_collation_set(Oid collid);
 static int	text_cmp(text *arg1, text *arg2, Oid collid);
-static bytea *bytea_catenate(bytea *t1, bytea *t2);
-static bytea *bytea_substring(Datum str,
-							  int S,
-							  int L,
-							  bool length_not_specified);
-static bytea *bytea_overlay(bytea *t1, bytea *t2, int sp, int sl);
 static void appendStringInfoText(StringInfo str, const text *t);
 static bool split_text(FunctionCallInfo fcinfo, SplitTextOutputData *tstate);
 static void split_text_accum_result(SplitTextOutputData *tstate,
@@ -279,307 +268,6 @@ text_to_cstring_buffer(const text *src, char *dst, size_t dst_len)
  *	 USER I/O ROUTINES														 *
  *****************************************************************************/
 
-
-#define VAL(CH)			((CH) - '0')
-#define DIG(VAL)		((VAL) + '0')
-
-/*
- *		byteain			- converts from printable representation of byte array
- *
- *		Non-printable characters must be passed as '\nnn' (octal) and are
- *		converted to internal form.  '\' must be passed as '\\'.
- *		ereport(ERROR, ...) if bad form.
- *
- *		BUGS:
- *				The input is scanned twice.
- *				The error checking of input is minimal.
- */
-Datum
-byteain(PG_FUNCTION_ARGS)
-{
-	char	   *inputText = PG_GETARG_CSTRING(0);
-	Node	   *escontext = fcinfo->context;
-	char	   *tp;
-	char	   *rp;
-	int			bc;
-	bytea	   *result;
-
-	/* Recognize hex input */
-	if (inputText[0] == '\\' && inputText[1] == 'x')
-	{
-		size_t		len = strlen(inputText);
-
-		bc = (len - 2) / 2 + VARHDRSZ;	/* maximum possible length */
-		result = palloc(bc);
-		bc = hex_decode_safe(inputText + 2, len - 2, VARDATA(result),
-							 escontext);
-		SET_VARSIZE(result, bc + VARHDRSZ); /* actual length */
-
-		PG_RETURN_BYTEA_P(result);
-	}
-
-	/* Else, it's the traditional escaped style */
-	for (bc = 0, tp = inputText; *tp != '\0'; bc++)
-	{
-		if (tp[0] != '\\')
-			tp++;
-		else if ((tp[0] == '\\') &&
-				 (tp[1] >= '0' && tp[1] <= '3') &&
-				 (tp[2] >= '0' && tp[2] <= '7') &&
-				 (tp[3] >= '0' && tp[3] <= '7'))
-			tp += 4;
-		else if ((tp[0] == '\\') &&
-				 (tp[1] == '\\'))
-			tp += 2;
-		else
-		{
-			/*
-			 * one backslash, not followed by another or ### valid octal
-			 */
-			ereturn(escontext, (Datum) 0,
-					(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-					 errmsg("invalid input syntax for type %s", "bytea")));
-		}
-	}
-
-	bc += VARHDRSZ;
-
-	result = (bytea *) palloc(bc);
-	SET_VARSIZE(result, bc);
-
-	tp = inputText;
-	rp = VARDATA(result);
-	while (*tp != '\0')
-	{
-		if (tp[0] != '\\')
-			*rp++ = *tp++;
-		else if ((tp[0] == '\\') &&
-				 (tp[1] >= '0' && tp[1] <= '3') &&
-				 (tp[2] >= '0' && tp[2] <= '7') &&
-				 (tp[3] >= '0' && tp[3] <= '7'))
-		{
-			bc = VAL(tp[1]);
-			bc <<= 3;
-			bc += VAL(tp[2]);
-			bc <<= 3;
-			*rp++ = bc + VAL(tp[3]);
-
-			tp += 4;
-		}
-		else if ((tp[0] == '\\') &&
-				 (tp[1] == '\\'))
-		{
-			*rp++ = '\\';
-			tp += 2;
-		}
-		else
-		{
-			/*
-			 * We should never get here. The first pass should not allow it.
-			 */
-			ereturn(escontext, (Datum) 0,
-					(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-					 errmsg("invalid input syntax for type %s", "bytea")));
-		}
-	}
-
-	PG_RETURN_BYTEA_P(result);
-}
-
-/*
- *		byteaout		- converts to printable representation of byte array
- *
- *		In the traditional escaped format, non-printable characters are
- *		printed as '\nnn' (octal) and '\' as '\\'.
- */
-Datum
-byteaout(PG_FUNCTION_ARGS)
-{
-	bytea	   *vlena = PG_GETARG_BYTEA_PP(0);
-	char	   *result;
-	char	   *rp;
-
-	if (bytea_output == BYTEA_OUTPUT_HEX)
-	{
-		/* Print hex format */
-		rp = result = palloc(VARSIZE_ANY_EXHDR(vlena) * 2 + 2 + 1);
-		*rp++ = '\\';
-		*rp++ = 'x';
-		rp += hex_encode(VARDATA_ANY(vlena), VARSIZE_ANY_EXHDR(vlena), rp);
-	}
-	else if (bytea_output == BYTEA_OUTPUT_ESCAPE)
-	{
-		/* Print traditional escaped format */
-		char	   *vp;
-		uint64		len;
-		int			i;
-
-		len = 1;				/* empty string has 1 char */
-		vp = VARDATA_ANY(vlena);
-		for (i = VARSIZE_ANY_EXHDR(vlena); i != 0; i--, vp++)
-		{
-			if (*vp == '\\')
-				len += 2;
-			else if ((unsigned char) *vp < 0x20 || (unsigned char) *vp > 0x7e)
-				len += 4;
-			else
-				len++;
-		}
-
-		/*
-		 * In principle len can't overflow uint32 if the input fit in 1GB, but
-		 * for safety let's check rather than relying on palloc's internal
-		 * check.
-		 */
-		if (len > MaxAllocSize)
-			ereport(ERROR,
-					(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
-					 errmsg_internal("result of bytea output conversion is too large")));
-		rp = result = (char *) palloc(len);
-
-		vp = VARDATA_ANY(vlena);
-		for (i = VARSIZE_ANY_EXHDR(vlena); i != 0; i--, vp++)
-		{
-			if (*vp == '\\')
-			{
-				*rp++ = '\\';
-				*rp++ = '\\';
-			}
-			else if ((unsigned char) *vp < 0x20 || (unsigned char) *vp > 0x7e)
-			{
-				int			val;	/* holds unprintable chars */
-
-				val = *vp;
-				rp[0] = '\\';
-				rp[3] = DIG(val & 07);
-				val >>= 3;
-				rp[2] = DIG(val & 07);
-				val >>= 3;
-				rp[1] = DIG(val & 03);
-				rp += 4;
-			}
-			else
-				*rp++ = *vp;
-		}
-	}
-	else
-	{
-		elog(ERROR, "unrecognized \"bytea_output\" setting: %d",
-			 bytea_output);
-		rp = result = NULL;		/* keep compiler quiet */
-	}
-	*rp = '\0';
-	PG_RETURN_CSTRING(result);
-}
-
-/*
- *		bytearecv			- converts external binary format to bytea
- */
-Datum
-bytearecv(PG_FUNCTION_ARGS)
-{
-	StringInfo	buf = (StringInfo) PG_GETARG_POINTER(0);
-	bytea	   *result;
-	int			nbytes;
-
-	nbytes = buf->len - buf->cursor;
-	result = (bytea *) palloc(nbytes + VARHDRSZ);
-	SET_VARSIZE(result, nbytes + VARHDRSZ);
-	pq_copymsgbytes(buf, VARDATA(result), nbytes);
-	PG_RETURN_BYTEA_P(result);
-}
-
-/*
- *		byteasend			- converts bytea to binary format
- *
- * This is a special case: just copy the input...
- */
-Datum
-byteasend(PG_FUNCTION_ARGS)
-{
-	bytea	   *vlena = PG_GETARG_BYTEA_P_COPY(0);
-
-	PG_RETURN_BYTEA_P(vlena);
-}
-
-Datum
-bytea_string_agg_transfn(PG_FUNCTION_ARGS)
-{
-	StringInfo	state;
-
-	state = PG_ARGISNULL(0) ? NULL : (StringInfo) PG_GETARG_POINTER(0);
-
-	/* Append the value unless null, preceding it with the delimiter. */
-	if (!PG_ARGISNULL(1))
-	{
-		bytea	   *value = PG_GETARG_BYTEA_PP(1);
-		bool		isfirst = false;
-
-		/*
-		 * You might think we can just throw away the first delimiter, however
-		 * we must keep it as we may be a parallel worker doing partial
-		 * aggregation building a state to send to the main process.  We need
-		 * to keep the delimiter of every aggregation so that the combine
-		 * function can properly join up the strings of two separately
-		 * partially aggregated results.  The first delimiter is only stripped
-		 * off in the final function.  To know how much to strip off the front
-		 * of the string, we store the length of the first delimiter in the
-		 * StringInfo's cursor field, which we don't otherwise need here.
-		 */
-		if (state == NULL)
-		{
-			state = makeStringAggState(fcinfo);
-			isfirst = true;
-		}
-
-		if (!PG_ARGISNULL(2))
-		{
-			bytea	   *delim = PG_GETARG_BYTEA_PP(2);
-
-			appendBinaryStringInfo(state, VARDATA_ANY(delim),
-								   VARSIZE_ANY_EXHDR(delim));
-			if (isfirst)
-				state->cursor = VARSIZE_ANY_EXHDR(delim);
-		}
-
-		appendBinaryStringInfo(state, VARDATA_ANY(value),
-							   VARSIZE_ANY_EXHDR(value));
-	}
-
-	/*
-	 * The transition type for string_agg() is declared to be "internal",
-	 * which is a pass-by-value type the same size as a pointer.
-	 */
-	if (state)
-		PG_RETURN_POINTER(state);
-	PG_RETURN_NULL();
-}
-
-Datum
-bytea_string_agg_finalfn(PG_FUNCTION_ARGS)
-{
-	StringInfo	state;
-
-	/* cannot be called directly because of internal-type argument */
-	Assert(AggCheckCallContext(fcinfo, NULL));
-
-	state = PG_ARGISNULL(0) ? NULL : (StringInfo) PG_GETARG_POINTER(0);
-
-	if (state != NULL)
-	{
-		/* As per comment in transfn, strip data before the cursor position */
-		bytea	   *result;
-		int			strippedlen = state->len - state->cursor;
-
-		result = (bytea *) palloc(strippedlen + VARHDRSZ);
-		SET_VARSIZE(result, strippedlen + VARHDRSZ);
-		memcpy(VARDATA(result), &state->data[state->cursor], strippedlen);
-		PG_RETURN_BYTEA_P(result);
-	}
-	else
-		PG_RETURN_NULL();
-}
-
 /*
  *		textin			- converts cstring to internal representation
  */
@@ -2959,552 +2647,91 @@ bttext_pattern_sortsupport(PG_FUNCTION_ARGS)
 }
 
 
-/*-------------------------------------------------------------
- * byteaoctetlen
- *
- * get the number of bytes contained in an instance of type 'bytea'
- *-------------------------------------------------------------
+/* text_name()
+ * Converts a text type to a Name type.
  */
 Datum
-byteaoctetlen(PG_FUNCTION_ARGS)
+text_name(PG_FUNCTION_ARGS)
 {
-	Datum		str = PG_GETARG_DATUM(0);
+	text	   *s = PG_GETARG_TEXT_PP(0);
+	Name		result;
+	int			len;
 
-	/* We need not detoast the input at all */
-	PG_RETURN_INT32(toast_raw_datum_size(str) - VARHDRSZ);
+	len = VARSIZE_ANY_EXHDR(s);
+
+	/* Truncate oversize input */
+	if (len >= NAMEDATALEN)
+		len = pg_mbcliplen(VARDATA_ANY(s), len, NAMEDATALEN - 1);
+
+	/* We use palloc0 here to ensure result is zero-padded */
+	result = (Name) palloc0(NAMEDATALEN);
+	memcpy(NameStr(*result), VARDATA_ANY(s), len);
+
+	PG_RETURN_NAME(result);
 }
 
-/*
- * byteacat -
- *	  takes two bytea* and returns a bytea* that is the concatenation of
- *	  the two.
- *
- * Cloned from textcat and modified as required.
+/* name_text()
+ * Converts a Name type to a text type.
  */
 Datum
-byteacat(PG_FUNCTION_ARGS)
+name_text(PG_FUNCTION_ARGS)
 {
-	bytea	   *t1 = PG_GETARG_BYTEA_PP(0);
-	bytea	   *t2 = PG_GETARG_BYTEA_PP(1);
+	Name		s = PG_GETARG_NAME(0);
 
-	PG_RETURN_BYTEA_P(bytea_catenate(t1, t2));
+	PG_RETURN_TEXT_P(cstring_to_text(NameStr(*s)));
 }
 
+
 /*
- * bytea_catenate
- *	Guts of byteacat(), broken out so it can be used by other functions
+ * textToQualifiedNameList - convert a text object to list of names
  *
- * Arguments can be in short-header form, but not compressed or out-of-line
+ * This implements the input parsing needed by nextval() and other
+ * functions that take a text parameter representing a qualified name.
+ * We split the name at dots, downcase if not double-quoted, and
+ * truncate names if they're too long.
  */
-static bytea *
-bytea_catenate(bytea *t1, bytea *t2)
+List *
+textToQualifiedNameList(text *textval)
 {
-	bytea	   *result;
-	int			len1,
-				len2,
-				len;
-	char	   *ptr;
+	char	   *rawname;
+	List	   *result = NIL;
+	List	   *namelist;
+	ListCell   *l;
 
-	len1 = VARSIZE_ANY_EXHDR(t1);
-	len2 = VARSIZE_ANY_EXHDR(t2);
+	/* Convert to C string (handles possible detoasting). */
+	/* Note we rely on being able to modify rawname below. */
+	rawname = text_to_cstring(textval);
 
-	/* paranoia ... probably should throw error instead? */
-	if (len1 < 0)
-		len1 = 0;
-	if (len2 < 0)
-		len2 = 0;
+	if (!SplitIdentifierString(rawname, '.', &namelist))
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_NAME),
+				 errmsg("invalid name syntax")));
 
-	len = len1 + len2 + VARHDRSZ;
-	result = (bytea *) palloc(len);
+	if (namelist == NIL)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_NAME),
+				 errmsg("invalid name syntax")));
 
-	/* Set size of result string... */
-	SET_VARSIZE(result, len);
+	foreach(l, namelist)
+	{
+		char	   *curname = (char *) lfirst(l);
 
-	/* Fill data field of result string... */
-	ptr = VARDATA(result);
-	if (len1 > 0)
-		memcpy(ptr, VARDATA_ANY(t1), len1);
-	if (len2 > 0)
-		memcpy(ptr + len1, VARDATA_ANY(t2), len2);
+		result = lappend(result, makeString(pstrdup(curname)));
+	}
+
+	pfree(rawname);
+	list_free(namelist);
 
 	return result;
 }
 
-#define PG_STR_GET_BYTEA(str_) \
-	DatumGetByteaPP(DirectFunctionCall1(byteain, CStringGetDatum(str_)))
-
 /*
- * bytea_substr()
- * Return a substring starting at the specified position.
- * Cloned from text_substr and modified as required.
+ * SplitIdentifierString --- parse a string containing identifiers
  *
- * Input:
- *	- string
- *	- starting position (is one-based)
- *	- string length (optional)
- *
- * If the starting position is zero or less, then return from the start of the string
- * adjusting the length to be consistent with the "negative start" per SQL.
- * If the length is less than zero, an ERROR is thrown. If no third argument
- * (length) is provided, the length to the end of the string is assumed.
- */
-Datum
-bytea_substr(PG_FUNCTION_ARGS)
-{
-	PG_RETURN_BYTEA_P(bytea_substring(PG_GETARG_DATUM(0),
-									  PG_GETARG_INT32(1),
-									  PG_GETARG_INT32(2),
-									  false));
-}
-
-/*
- * bytea_substr_no_len -
- *	  Wrapper to avoid opr_sanity failure due to
- *	  one function accepting a different number of args.
- */
-Datum
-bytea_substr_no_len(PG_FUNCTION_ARGS)
-{
-	PG_RETURN_BYTEA_P(bytea_substring(PG_GETARG_DATUM(0),
-									  PG_GETARG_INT32(1),
-									  -1,
-									  true));
-}
-
-static bytea *
-bytea_substring(Datum str,
-				int S,
-				int L,
-				bool length_not_specified)
-{
-	int32		S1;				/* adjusted start position */
-	int32		L1;				/* adjusted substring length */
-	int32		E;				/* end position */
-
-	/*
-	 * The logic here should generally match text_substring().
-	 */
-	S1 = Max(S, 1);
-
-	if (length_not_specified)
-	{
-		/*
-		 * Not passed a length - DatumGetByteaPSlice() grabs everything to the
-		 * end of the string if we pass it a negative value for length.
-		 */
-		L1 = -1;
-	}
-	else if (L < 0)
-	{
-		/* SQL99 says to throw an error for E < S, i.e., negative length */
-		ereport(ERROR,
-				(errcode(ERRCODE_SUBSTRING_ERROR),
-				 errmsg("negative substring length not allowed")));
-		L1 = -1;				/* silence stupider compilers */
-	}
-	else if (pg_add_s32_overflow(S, L, &E))
-	{
-		/*
-		 * L could be large enough for S + L to overflow, in which case the
-		 * substring must run to end of string.
-		 */
-		L1 = -1;
-	}
-	else
-	{
-		/*
-		 * A zero or negative value for the end position can happen if the
-		 * start was negative or one. SQL99 says to return a zero-length
-		 * string.
-		 */
-		if (E < 1)
-			return PG_STR_GET_BYTEA("");
-
-		L1 = E - S1;
-	}
-
-	/*
-	 * If the start position is past the end of the string, SQL99 says to
-	 * return a zero-length string -- DatumGetByteaPSlice() will do that for
-	 * us.  We need only convert S1 to zero-based starting position.
-	 */
-	return DatumGetByteaPSlice(str, S1 - 1, L1);
-}
-
-/*
- * byteaoverlay
- *	Replace specified substring of first string with second
- *
- * The SQL standard defines OVERLAY() in terms of substring and concatenation.
- * This code is a direct implementation of what the standard says.
- */
-Datum
-byteaoverlay(PG_FUNCTION_ARGS)
-{
-	bytea	   *t1 = PG_GETARG_BYTEA_PP(0);
-	bytea	   *t2 = PG_GETARG_BYTEA_PP(1);
-	int			sp = PG_GETARG_INT32(2);	/* substring start position */
-	int			sl = PG_GETARG_INT32(3);	/* substring length */
-
-	PG_RETURN_BYTEA_P(bytea_overlay(t1, t2, sp, sl));
-}
-
-Datum
-byteaoverlay_no_len(PG_FUNCTION_ARGS)
-{
-	bytea	   *t1 = PG_GETARG_BYTEA_PP(0);
-	bytea	   *t2 = PG_GETARG_BYTEA_PP(1);
-	int			sp = PG_GETARG_INT32(2);	/* substring start position */
-	int			sl;
-
-	sl = VARSIZE_ANY_EXHDR(t2); /* defaults to length(t2) */
-	PG_RETURN_BYTEA_P(bytea_overlay(t1, t2, sp, sl));
-}
-
-static bytea *
-bytea_overlay(bytea *t1, bytea *t2, int sp, int sl)
-{
-	bytea	   *result;
-	bytea	   *s1;
-	bytea	   *s2;
-	int			sp_pl_sl;
-
-	/*
-	 * Check for possible integer-overflow cases.  For negative sp, throw a
-	 * "substring length" error because that's what should be expected
-	 * according to the spec's definition of OVERLAY().
-	 */
-	if (sp <= 0)
-		ereport(ERROR,
-				(errcode(ERRCODE_SUBSTRING_ERROR),
-				 errmsg("negative substring length not allowed")));
-	if (pg_add_s32_overflow(sp, sl, &sp_pl_sl))
-		ereport(ERROR,
-				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
-				 errmsg("integer out of range")));
-
-	s1 = bytea_substring(PointerGetDatum(t1), 1, sp - 1, false);
-	s2 = bytea_substring(PointerGetDatum(t1), sp_pl_sl, -1, true);
-	result = bytea_catenate(s1, t2);
-	result = bytea_catenate(result, s2);
-
-	return result;
-}
-
-/*
- * bit_count
- */
-Datum
-bytea_bit_count(PG_FUNCTION_ARGS)
-{
-	bytea	   *t1 = PG_GETARG_BYTEA_PP(0);
-
-	PG_RETURN_INT64(pg_popcount(VARDATA_ANY(t1), VARSIZE_ANY_EXHDR(t1)));
-}
-
-/*
- * byteapos -
- *	  Return the position of the specified substring.
- *	  Implements the SQL POSITION() function.
- * Cloned from textpos and modified as required.
- */
-Datum
-byteapos(PG_FUNCTION_ARGS)
-{
-	bytea	   *t1 = PG_GETARG_BYTEA_PP(0);
-	bytea	   *t2 = PG_GETARG_BYTEA_PP(1);
-	int			pos;
-	int			px,
-				p;
-	int			len1,
-				len2;
-	char	   *p1,
-			   *p2;
-
-	len1 = VARSIZE_ANY_EXHDR(t1);
-	len2 = VARSIZE_ANY_EXHDR(t2);
-
-	if (len2 <= 0)
-		PG_RETURN_INT32(1);		/* result for empty pattern */
-
-	p1 = VARDATA_ANY(t1);
-	p2 = VARDATA_ANY(t2);
-
-	pos = 0;
-	px = (len1 - len2);
-	for (p = 0; p <= px; p++)
-	{
-		if ((*p2 == *p1) && (memcmp(p1, p2, len2) == 0))
-		{
-			pos = p + 1;
-			break;
-		};
-		p1++;
-	};
-
-	PG_RETURN_INT32(pos);
-}
-
-/*-------------------------------------------------------------
- * byteaGetByte
- *
- * this routine treats "bytea" as an array of bytes.
- * It returns the Nth byte (a number between 0 and 255).
- *-------------------------------------------------------------
- */
-Datum
-byteaGetByte(PG_FUNCTION_ARGS)
-{
-	bytea	   *v = PG_GETARG_BYTEA_PP(0);
-	int32		n = PG_GETARG_INT32(1);
-	int			len;
-	int			byte;
-
-	len = VARSIZE_ANY_EXHDR(v);
-
-	if (n < 0 || n >= len)
-		ereport(ERROR,
-				(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
-				 errmsg("index %d out of valid range, 0..%d",
-						n, len - 1)));
-
-	byte = ((unsigned char *) VARDATA_ANY(v))[n];
-
-	PG_RETURN_INT32(byte);
-}
-
-/*-------------------------------------------------------------
- * byteaGetBit
- *
- * This routine treats a "bytea" type like an array of bits.
- * It returns the value of the Nth bit (0 or 1).
- *
- *-------------------------------------------------------------
- */
-Datum
-byteaGetBit(PG_FUNCTION_ARGS)
-{
-	bytea	   *v = PG_GETARG_BYTEA_PP(0);
-	int64		n = PG_GETARG_INT64(1);
-	int			byteNo,
-				bitNo;
-	int			len;
-	int			byte;
-
-	len = VARSIZE_ANY_EXHDR(v);
-
-	if (n < 0 || n >= (int64) len * 8)
-		ereport(ERROR,
-				(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
-				 errmsg("index %" PRId64 " out of valid range, 0..%" PRId64,
-						n, (int64) len * 8 - 1)));
-
-	/* n/8 is now known < len, so safe to cast to int */
-	byteNo = (int) (n / 8);
-	bitNo = (int) (n % 8);
-
-	byte = ((unsigned char *) VARDATA_ANY(v))[byteNo];
-
-	if (byte & (1 << bitNo))
-		PG_RETURN_INT32(1);
-	else
-		PG_RETURN_INT32(0);
-}
-
-/*-------------------------------------------------------------
- * byteaSetByte
- *
- * Given an instance of type 'bytea' creates a new one with
- * the Nth byte set to the given value.
- *
- *-------------------------------------------------------------
- */
-Datum
-byteaSetByte(PG_FUNCTION_ARGS)
-{
-	bytea	   *res = PG_GETARG_BYTEA_P_COPY(0);
-	int32		n = PG_GETARG_INT32(1);
-	int32		newByte = PG_GETARG_INT32(2);
-	int			len;
-
-	len = VARSIZE(res) - VARHDRSZ;
-
-	if (n < 0 || n >= len)
-		ereport(ERROR,
-				(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
-				 errmsg("index %d out of valid range, 0..%d",
-						n, len - 1)));
-
-	/*
-	 * Now set the byte.
-	 */
-	((unsigned char *) VARDATA(res))[n] = newByte;
-
-	PG_RETURN_BYTEA_P(res);
-}
-
-/*-------------------------------------------------------------
- * byteaSetBit
- *
- * Given an instance of type 'bytea' creates a new one with
- * the Nth bit set to the given value.
- *
- *-------------------------------------------------------------
- */
-Datum
-byteaSetBit(PG_FUNCTION_ARGS)
-{
-	bytea	   *res = PG_GETARG_BYTEA_P_COPY(0);
-	int64		n = PG_GETARG_INT64(1);
-	int32		newBit = PG_GETARG_INT32(2);
-	int			len;
-	int			oldByte,
-				newByte;
-	int			byteNo,
-				bitNo;
-
-	len = VARSIZE(res) - VARHDRSZ;
-
-	if (n < 0 || n >= (int64) len * 8)
-		ereport(ERROR,
-				(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
-				 errmsg("index %" PRId64 " out of valid range, 0..%" PRId64,
-						n, (int64) len * 8 - 1)));
-
-	/* n/8 is now known < len, so safe to cast to int */
-	byteNo = (int) (n / 8);
-	bitNo = (int) (n % 8);
-
-	/*
-	 * sanity check!
-	 */
-	if (newBit != 0 && newBit != 1)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("new bit must be 0 or 1")));
-
-	/*
-	 * Update the byte.
-	 */
-	oldByte = ((unsigned char *) VARDATA(res))[byteNo];
-
-	if (newBit == 0)
-		newByte = oldByte & (~(1 << bitNo));
-	else
-		newByte = oldByte | (1 << bitNo);
-
-	((unsigned char *) VARDATA(res))[byteNo] = newByte;
-
-	PG_RETURN_BYTEA_P(res);
-}
-
-/*
- * Return reversed bytea
- */
-Datum
-bytea_reverse(PG_FUNCTION_ARGS)
-{
-	bytea	   *v = PG_GETARG_BYTEA_PP(0);
-	const char *p = VARDATA_ANY(v);
-	int			len = VARSIZE_ANY_EXHDR(v);
-	const char *endp = p + len;
-	bytea	   *result = palloc(len + VARHDRSZ);
-	char	   *dst = (char *) VARDATA(result) + len;
-
-	SET_VARSIZE(result, len + VARHDRSZ);
-
-	while (p < endp)
-		*(--dst) = *p++;
-
-	PG_RETURN_BYTEA_P(result);
-}
-
-
-/* text_name()
- * Converts a text type to a Name type.
- */
-Datum
-text_name(PG_FUNCTION_ARGS)
-{
-	text	   *s = PG_GETARG_TEXT_PP(0);
-	Name		result;
-	int			len;
-
-	len = VARSIZE_ANY_EXHDR(s);
-
-	/* Truncate oversize input */
-	if (len >= NAMEDATALEN)
-		len = pg_mbcliplen(VARDATA_ANY(s), len, NAMEDATALEN - 1);
-
-	/* We use palloc0 here to ensure result is zero-padded */
-	result = (Name) palloc0(NAMEDATALEN);
-	memcpy(NameStr(*result), VARDATA_ANY(s), len);
-
-	PG_RETURN_NAME(result);
-}
-
-/* name_text()
- * Converts a Name type to a text type.
- */
-Datum
-name_text(PG_FUNCTION_ARGS)
-{
-	Name		s = PG_GETARG_NAME(0);
-
-	PG_RETURN_TEXT_P(cstring_to_text(NameStr(*s)));
-}
-
-
-/*
- * textToQualifiedNameList - convert a text object to list of names
- *
- * This implements the input parsing needed by nextval() and other
- * functions that take a text parameter representing a qualified name.
- * We split the name at dots, downcase if not double-quoted, and
- * truncate names if they're too long.
- */
-List *
-textToQualifiedNameList(text *textval)
-{
-	char	   *rawname;
-	List	   *result = NIL;
-	List	   *namelist;
-	ListCell   *l;
-
-	/* Convert to C string (handles possible detoasting). */
-	/* Note we rely on being able to modify rawname below. */
-	rawname = text_to_cstring(textval);
-
-	if (!SplitIdentifierString(rawname, '.', &namelist))
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_NAME),
-				 errmsg("invalid name syntax")));
-
-	if (namelist == NIL)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_NAME),
-				 errmsg("invalid name syntax")));
-
-	foreach(l, namelist)
-	{
-		char	   *curname = (char *) lfirst(l);
-
-		result = lappend(result, makeString(pstrdup(curname)));
-	}
-
-	pfree(rawname);
-	list_free(namelist);
-
-	return result;
-}
-
-/*
- * SplitIdentifierString --- parse a string containing identifiers
- *
- * This is the guts of textToQualifiedNameList, and is exported for use in
- * other situations such as parsing GUC variables.  In the GUC case, it's
- * important to avoid memory leaks, so the API is designed to minimize the
- * amount of stuff that needs to be allocated and freed.
+ * This is the guts of textToQualifiedNameList, and is exported for use in
+ * other situations such as parsing GUC variables.  In the GUC case, it's
+ * important to avoid memory leaks, so the API is designed to minimize the
+ * amount of stuff that needs to be allocated and freed.
  *
  * Inputs:
  *	rawstring: the input string; must be overwritable!	On return, it's
@@ -3849,331 +3076,6 @@ SplitGUCList(char *rawstring, char separator,
 	return true;
 }
 
-
-/*****************************************************************************
- *	Comparison Functions used for bytea
- *
- * Note: btree indexes need these routines not to leak memory; therefore,
- * be careful to free working copies of toasted datums.  Most places don't
- * need to be so careful.
- *****************************************************************************/
-
-Datum
-byteaeq(PG_FUNCTION_ARGS)
-{
-	Datum		arg1 = PG_GETARG_DATUM(0);
-	Datum		arg2 = PG_GETARG_DATUM(1);
-	bool		result;
-	Size		len1,
-				len2;
-
-	/*
-	 * We can use a fast path for unequal lengths, which might save us from
-	 * having to detoast one or both values.
-	 */
-	len1 = toast_raw_datum_size(arg1);
-	len2 = toast_raw_datum_size(arg2);
-	if (len1 != len2)
-		result = false;
-	else
-	{
-		bytea	   *barg1 = DatumGetByteaPP(arg1);
-		bytea	   *barg2 = DatumGetByteaPP(arg2);
-
-		result = (memcmp(VARDATA_ANY(barg1), VARDATA_ANY(barg2),
-						 len1 - VARHDRSZ) == 0);
-
-		PG_FREE_IF_COPY(barg1, 0);
-		PG_FREE_IF_COPY(barg2, 1);
-	}
-
-	PG_RETURN_BOOL(result);
-}
-
-Datum
-byteane(PG_FUNCTION_ARGS)
-{
-	Datum		arg1 = PG_GETARG_DATUM(0);
-	Datum		arg2 = PG_GETARG_DATUM(1);
-	bool		result;
-	Size		len1,
-				len2;
-
-	/*
-	 * We can use a fast path for unequal lengths, which might save us from
-	 * having to detoast one or both values.
-	 */
-	len1 = toast_raw_datum_size(arg1);
-	len2 = toast_raw_datum_size(arg2);
-	if (len1 != len2)
-		result = true;
-	else
-	{
-		bytea	   *barg1 = DatumGetByteaPP(arg1);
-		bytea	   *barg2 = DatumGetByteaPP(arg2);
-
-		result = (memcmp(VARDATA_ANY(barg1), VARDATA_ANY(barg2),
-						 len1 - VARHDRSZ) != 0);
-
-		PG_FREE_IF_COPY(barg1, 0);
-		PG_FREE_IF_COPY(barg2, 1);
-	}
-
-	PG_RETURN_BOOL(result);
-}
-
-Datum
-bytealt(PG_FUNCTION_ARGS)
-{
-	bytea	   *arg1 = PG_GETARG_BYTEA_PP(0);
-	bytea	   *arg2 = PG_GETARG_BYTEA_PP(1);
-	int			len1,
-				len2;
-	int			cmp;
-
-	len1 = VARSIZE_ANY_EXHDR(arg1);
-	len2 = VARSIZE_ANY_EXHDR(arg2);
-
-	cmp = memcmp(VARDATA_ANY(arg1), VARDATA_ANY(arg2), Min(len1, len2));
-
-	PG_FREE_IF_COPY(arg1, 0);
-	PG_FREE_IF_COPY(arg2, 1);
-
-	PG_RETURN_BOOL((cmp < 0) || ((cmp == 0) && (len1 < len2)));
-}
-
-Datum
-byteale(PG_FUNCTION_ARGS)
-{
-	bytea	   *arg1 = PG_GETARG_BYTEA_PP(0);
-	bytea	   *arg2 = PG_GETARG_BYTEA_PP(1);
-	int			len1,
-				len2;
-	int			cmp;
-
-	len1 = VARSIZE_ANY_EXHDR(arg1);
-	len2 = VARSIZE_ANY_EXHDR(arg2);
-
-	cmp = memcmp(VARDATA_ANY(arg1), VARDATA_ANY(arg2), Min(len1, len2));
-
-	PG_FREE_IF_COPY(arg1, 0);
-	PG_FREE_IF_COPY(arg2, 1);
-
-	PG_RETURN_BOOL((cmp < 0) || ((cmp == 0) && (len1 <= len2)));
-}
-
-Datum
-byteagt(PG_FUNCTION_ARGS)
-{
-	bytea	   *arg1 = PG_GETARG_BYTEA_PP(0);
-	bytea	   *arg2 = PG_GETARG_BYTEA_PP(1);
-	int			len1,
-				len2;
-	int			cmp;
-
-	len1 = VARSIZE_ANY_EXHDR(arg1);
-	len2 = VARSIZE_ANY_EXHDR(arg2);
-
-	cmp = memcmp(VARDATA_ANY(arg1), VARDATA_ANY(arg2), Min(len1, len2));
-
-	PG_FREE_IF_COPY(arg1, 0);
-	PG_FREE_IF_COPY(arg2, 1);
-
-	PG_RETURN_BOOL((cmp > 0) || ((cmp == 0) && (len1 > len2)));
-}
-
-Datum
-byteage(PG_FUNCTION_ARGS)
-{
-	bytea	   *arg1 = PG_GETARG_BYTEA_PP(0);
-	bytea	   *arg2 = PG_GETARG_BYTEA_PP(1);
-	int			len1,
-				len2;
-	int			cmp;
-
-	len1 = VARSIZE_ANY_EXHDR(arg1);
-	len2 = VARSIZE_ANY_EXHDR(arg2);
-
-	cmp = memcmp(VARDATA_ANY(arg1), VARDATA_ANY(arg2), Min(len1, len2));
-
-	PG_FREE_IF_COPY(arg1, 0);
-	PG_FREE_IF_COPY(arg2, 1);
-
-	PG_RETURN_BOOL((cmp > 0) || ((cmp == 0) && (len1 >= len2)));
-}
-
-Datum
-byteacmp(PG_FUNCTION_ARGS)
-{
-	bytea	   *arg1 = PG_GETARG_BYTEA_PP(0);
-	bytea	   *arg2 = PG_GETARG_BYTEA_PP(1);
-	int			len1,
-				len2;
-	int			cmp;
-
-	len1 = VARSIZE_ANY_EXHDR(arg1);
-	len2 = VARSIZE_ANY_EXHDR(arg2);
-
-	cmp = memcmp(VARDATA_ANY(arg1), VARDATA_ANY(arg2), Min(len1, len2));
-	if ((cmp == 0) && (len1 != len2))
-		cmp = (len1 < len2) ? -1 : 1;
-
-	PG_FREE_IF_COPY(arg1, 0);
-	PG_FREE_IF_COPY(arg2, 1);
-
-	PG_RETURN_INT32(cmp);
-}
-
-Datum
-bytea_larger(PG_FUNCTION_ARGS)
-{
-	bytea	   *arg1 = PG_GETARG_BYTEA_PP(0);
-	bytea	   *arg2 = PG_GETARG_BYTEA_PP(1);
-	bytea	   *result;
-	int			len1,
-				len2;
-	int			cmp;
-
-	len1 = VARSIZE_ANY_EXHDR(arg1);
-	len2 = VARSIZE_ANY_EXHDR(arg2);
-
-	cmp = memcmp(VARDATA_ANY(arg1), VARDATA_ANY(arg2), Min(len1, len2));
-	result = ((cmp > 0) || ((cmp == 0) && (len1 > len2)) ? arg1 : arg2);
-
-	PG_RETURN_BYTEA_P(result);
-}
-
-Datum
-bytea_smaller(PG_FUNCTION_ARGS)
-{
-	bytea	   *arg1 = PG_GETARG_BYTEA_PP(0);
-	bytea	   *arg2 = PG_GETARG_BYTEA_PP(1);
-	bytea	   *result;
-	int			len1,
-				len2;
-	int			cmp;
-
-	len1 = VARSIZE_ANY_EXHDR(arg1);
-	len2 = VARSIZE_ANY_EXHDR(arg2);
-
-	cmp = memcmp(VARDATA_ANY(arg1), VARDATA_ANY(arg2), Min(len1, len2));
-	result = ((cmp < 0) || ((cmp == 0) && (len1 < len2)) ? arg1 : arg2);
-
-	PG_RETURN_BYTEA_P(result);
-}
-
-Datum
-bytea_sortsupport(PG_FUNCTION_ARGS)
-{
-	SortSupport ssup = (SortSupport) PG_GETARG_POINTER(0);
-	MemoryContext oldcontext;
-
-	oldcontext = MemoryContextSwitchTo(ssup->ssup_cxt);
-
-	/* Use generic string SortSupport, forcing "C" collation */
-	varstr_sortsupport(ssup, BYTEAOID, C_COLLATION_OID);
-
-	MemoryContextSwitchTo(oldcontext);
-
-	PG_RETURN_VOID();
-}
-
-/* Cast bytea -> int2 */
-Datum
-bytea_int2(PG_FUNCTION_ARGS)
-{
-	bytea	   *v = PG_GETARG_BYTEA_PP(0);
-	int			len = VARSIZE_ANY_EXHDR(v);
-	uint16		result;
-
-	/* Check that the byte array is not too long */
-	if (len > sizeof(result))
-		ereport(ERROR,
-				errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
-				errmsg("smallint out of range"));
-
-	/* Convert it to an integer; most significant bytes come first */
-	result = 0;
-	for (int i = 0; i < len; i++)
-	{
-		result <<= BITS_PER_BYTE;
-		result |= ((unsigned char *) VARDATA_ANY(v))[i];
-	}
-
-	PG_RETURN_INT16(result);
-}
-
-/* Cast bytea -> int4 */
-Datum
-bytea_int4(PG_FUNCTION_ARGS)
-{
-	bytea	   *v = PG_GETARG_BYTEA_PP(0);
-	int			len = VARSIZE_ANY_EXHDR(v);
-	uint32		result;
-
-	/* Check that the byte array is not too long */
-	if (len > sizeof(result))
-		ereport(ERROR,
-				errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
-				errmsg("integer out of range"));
-
-	/* Convert it to an integer; most significant bytes come first */
-	result = 0;
-	for (int i = 0; i < len; i++)
-	{
-		result <<= BITS_PER_BYTE;
-		result |= ((unsigned char *) VARDATA_ANY(v))[i];
-	}
-
-	PG_RETURN_INT32(result);
-}
-
-/* Cast bytea -> int8 */
-Datum
-bytea_int8(PG_FUNCTION_ARGS)
-{
-	bytea	   *v = PG_GETARG_BYTEA_PP(0);
-	int			len = VARSIZE_ANY_EXHDR(v);
-	uint64		result;
-
-	/* Check that the byte array is not too long */
-	if (len > sizeof(result))
-		ereport(ERROR,
-				errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
-				errmsg("bigint out of range"));
-
-	/* Convert it to an integer; most significant bytes come first */
-	result = 0;
-	for (int i = 0; i < len; i++)
-	{
-		result <<= BITS_PER_BYTE;
-		result |= ((unsigned char *) VARDATA_ANY(v))[i];
-	}
-
-	PG_RETURN_INT64(result);
-}
-
-/* Cast int2 -> bytea; can just use int2send() */
-Datum
-int2_bytea(PG_FUNCTION_ARGS)
-{
-	return int2send(fcinfo);
-}
-
-/* Cast int4 -> bytea; can just use int4send() */
-Datum
-int4_bytea(PG_FUNCTION_ARGS)
-{
-	return int4send(fcinfo);
-}
-
-/* Cast int8 -> bytea; can just use int8send() */
-Datum
-int8_bytea(PG_FUNCTION_ARGS)
-{
-	return int8send(fcinfo);
-}
-
 /*
  * appendStringInfoText
  *
diff --git a/src/backend/utils/adt/xml.c b/src/backend/utils/adt/xml.c
index a4150bff2eaea..182e8f75db75c 100644
--- a/src/backend/utils/adt/xml.c
+++ b/src/backend/utils/adt/xml.c
@@ -529,14 +529,36 @@ xmltext(PG_FUNCTION_ARGS)
 #ifdef USE_LIBXML
 	text	   *arg = PG_GETARG_TEXT_PP(0);
 	text	   *result;
-	xmlChar    *xmlbuf = NULL;
+	volatile xmlChar *xmlbuf = NULL;
+	PgXmlErrorContext *xmlerrcxt;
+
+	/* First we gotta spin up some error handling. */
+	xmlerrcxt = pg_xml_init(PG_XML_STRICTNESS_ALL);
+
+	PG_TRY();
+	{
+		xmlbuf = xmlEncodeSpecialChars(NULL, xml_text2xmlChar(arg));
+
+		if (xmlbuf == NULL || xmlerrcxt->err_occurred)
+			xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY,
+						"could not allocate xmlChar");
 
-	xmlbuf = xmlEncodeSpecialChars(NULL, xml_text2xmlChar(arg));
+		result = cstring_to_text_with_len((const char *) xmlbuf,
+										  xmlStrlen((const xmlChar *) xmlbuf));
+	}
+	PG_CATCH();
+	{
+		if (xmlbuf)
+			xmlFree((xmlChar *) xmlbuf);
 
-	Assert(xmlbuf);
+		pg_xml_done(xmlerrcxt, true);
+		PG_RE_THROW();
+	}
+	PG_END_TRY();
+
+	xmlFree((xmlChar *) xmlbuf);
+	pg_xml_done(xmlerrcxt, false);
 
-	result = cstring_to_text_with_len((const char *) xmlbuf, xmlStrlen(xmlbuf));
-	xmlFree(xmlbuf);
 	PG_RETURN_XML_P(result);
 #else
 	NO_XML_SUPPORT();
@@ -663,7 +685,7 @@ xmltotext_with_options(xmltype *data, XmlOptionType xmloption_arg, bool indent)
 	volatile xmlBufferPtr buf = NULL;
 	volatile xmlSaveCtxtPtr ctxt = NULL;
 	ErrorSaveContext escontext = {T_ErrorSaveContext};
-	PgXmlErrorContext *xmlerrcxt;
+	PgXmlErrorContext *volatile xmlerrcxt = NULL;
 #endif
 
 	if (xmloption_arg != XMLOPTION_DOCUMENT && !indent)
@@ -704,13 +726,18 @@ xmltotext_with_options(xmltype *data, XmlOptionType xmloption_arg, bool indent)
 		return (text *) data;
 	}
 
-	/* Otherwise, we gotta spin up some error handling. */
-	xmlerrcxt = pg_xml_init(PG_XML_STRICTNESS_ALL);
-
+	/*
+	 * Otherwise, we gotta spin up some error handling.  Unlike most other
+	 * routines in this module, we already have a libxml "doc" structure to
+	 * free, so we need to call pg_xml_init() inside the PG_TRY and be
+	 * prepared for it to fail (typically due to palloc OOM).
+	 */
 	PG_TRY();
 	{
 		size_t		decl_len = 0;
 
+		xmlerrcxt = pg_xml_init(PG_XML_STRICTNESS_ALL);
+
 		/* The serialized data will go into this buffer. */
 		buf = xmlBufferCreate();
 
@@ -770,7 +797,10 @@ xmltotext_with_options(xmltype *data, XmlOptionType xmloption_arg, bool indent)
 			if (oldroot != NULL)
 				xmlFreeNode(oldroot);
 
-			xmlAddChildList(root, content_nodes);
+			if (xmlAddChildList(root, content_nodes) == NULL ||
+				xmlerrcxt->err_occurred)
+				xml_ereport(xmlerrcxt, ERROR, ERRCODE_INTERNAL_ERROR,
+							"could not append xml node list");
 
 			/*
 			 * We use this node to insert newlines in the dump.  Note: in at
@@ -838,10 +868,10 @@ xmltotext_with_options(xmltype *data, XmlOptionType xmloption_arg, bool indent)
 			xmlSaveClose(ctxt);
 		if (buf)
 			xmlBufferFree(buf);
-		if (doc)
-			xmlFreeDoc(doc);
+		xmlFreeDoc(doc);
 
-		pg_xml_done(xmlerrcxt, true);
+		if (xmlerrcxt)
+			pg_xml_done(xmlerrcxt, true);
 
 		PG_RE_THROW();
 	}
@@ -931,7 +961,10 @@ xmlelement(XmlExpr *xexpr,
 			xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY,
 						"could not allocate xmlTextWriter");
 
-		xmlTextWriterStartElement(writer, (xmlChar *) xexpr->name);
+		if (xmlTextWriterStartElement(writer, (xmlChar *) xexpr->name) < 0 ||
+			xmlerrcxt->err_occurred)
+			xml_ereport(xmlerrcxt, ERROR, ERRCODE_INTERNAL_ERROR,
+						"could not start xml element");
 
 		forboth(arg, named_arg_strings, narg, xexpr->arg_names)
 		{
@@ -939,19 +972,30 @@ xmlelement(XmlExpr *xexpr,
 			char	   *argname = strVal(lfirst(narg));
 
 			if (str)
-				xmlTextWriterWriteAttribute(writer,
-											(xmlChar *) argname,
-											(xmlChar *) str);
+			{
+				if (xmlTextWriterWriteAttribute(writer,
+												(xmlChar *) argname,
+												(xmlChar *) str) < 0 ||
+					xmlerrcxt->err_occurred)
+					xml_ereport(xmlerrcxt, ERROR, ERRCODE_INTERNAL_ERROR,
+								"could not write xml attribute");
+			}
 		}
 
 		foreach(arg, arg_strings)
 		{
 			char	   *str = (char *) lfirst(arg);
 
-			xmlTextWriterWriteRaw(writer, (xmlChar *) str);
+			if (xmlTextWriterWriteRaw(writer, (xmlChar *) str) < 0 ||
+				xmlerrcxt->err_occurred)
+				xml_ereport(xmlerrcxt, ERROR, ERRCODE_INTERNAL_ERROR,
+							"could not write raw xml text");
 		}
 
-		xmlTextWriterEndElement(writer);
+		if (xmlTextWriterEndElement(writer) < 0 ||
+			xmlerrcxt->err_occurred)
+			xml_ereport(xmlerrcxt, ERROR, ERRCODE_INTERNAL_ERROR,
+						"could not end xml element");
 
 		/* we MUST do this now to flush data out to the buffer ... */
 		xmlFreeTextWriter(writer);
@@ -1725,7 +1769,7 @@ xml_doctype_in_content(const xmlChar *str)
  * xmloption_arg, but a DOCTYPE node in the input can force DOCUMENT mode).
  *
  * If parsed_nodes isn't NULL and we parse in CONTENT mode, the list
- * of parsed nodes from the xmlParseInNodeContext call will be returned
+ * of parsed nodes from the xmlParseBalancedChunkMemory call will be returned
  * to *parsed_nodes.  (It is caller's responsibility to free that.)
  *
  * Errors normally result in ereport(ERROR), but if escontext is an
@@ -1751,6 +1795,7 @@ xml_parse(text *data, XmlOptionType xmloption_arg,
 	PgXmlErrorContext *xmlerrcxt;
 	volatile xmlParserCtxtPtr ctxt = NULL;
 	volatile xmlDocPtr doc = NULL;
+	volatile int save_keep_blanks = -1;
 
 	/*
 	 * This step looks annoyingly redundant, but we must do it to have a
@@ -1778,7 +1823,6 @@ xml_parse(text *data, XmlOptionType xmloption_arg,
 	PG_TRY();
 	{
 		bool		parse_as_document = false;
-		int			options;
 		int			res_code;
 		size_t		count = 0;
 		xmlChar    *version = NULL;
@@ -1809,18 +1853,6 @@ xml_parse(text *data, XmlOptionType xmloption_arg,
 				parse_as_document = true;
 		}
 
-		/*
-		 * Select parse options.
-		 *
-		 * Note that here we try to apply DTD defaults (XML_PARSE_DTDATTR)
-		 * according to SQL/XML:2008 GR 10.16.7.d: 'Default values defined by
-		 * internal DTD are applied'.  As for external DTDs, we try to support
-		 * them too (see SQL/XML:2008 GR 10.16.7.e), but that doesn't really
-		 * happen because xmlPgEntityLoader prevents it.
-		 */
-		options = XML_PARSE_NOENT | XML_PARSE_DTDATTR
-			| (preserve_whitespace ? 0 : XML_PARSE_NOBLANKS);
-
 		/* initialize output parameters */
 		if (parsed_xmloptiontype != NULL)
 			*parsed_xmloptiontype = parse_as_document ? XMLOPTION_DOCUMENT :
@@ -1830,11 +1862,26 @@ xml_parse(text *data, XmlOptionType xmloption_arg,
 
 		if (parse_as_document)
 		{
+			int			options;
+
+			/* set up parser context used by xmlCtxtReadDoc */
 			ctxt = xmlNewParserCtxt();
 			if (ctxt == NULL || xmlerrcxt->err_occurred)
 				xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY,
 							"could not allocate parser context");
 
+			/*
+			 * Select parse options.
+			 *
+			 * Note that here we try to apply DTD defaults (XML_PARSE_DTDATTR)
+			 * according to SQL/XML:2008 GR 10.16.7.d: 'Default values defined
+			 * by internal DTD are applied'.  As for external DTDs, we try to
+			 * support them too (see SQL/XML:2008 GR 10.16.7.e), but that
+			 * doesn't really happen because xmlPgEntityLoader prevents it.
+			 */
+			options = XML_PARSE_NOENT | XML_PARSE_DTDATTR
+				| (preserve_whitespace ? 0 : XML_PARSE_NOBLANKS);
+
 			doc = xmlCtxtReadDoc(ctxt, utf8string,
 								 NULL,	/* no URL */
 								 "UTF-8",
@@ -1856,10 +1903,7 @@ xml_parse(text *data, XmlOptionType xmloption_arg,
 		}
 		else
 		{
-			xmlNodePtr	root;
-			xmlNodePtr	oldroot PG_USED_FOR_ASSERTS_ONLY;
-
-			/* set up document with empty root node to be the context node */
+			/* set up document that xmlParseBalancedChunkMemory will add to */
 			doc = xmlNewDoc(version);
 			if (doc == NULL || xmlerrcxt->err_occurred)
 				xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY,
@@ -1872,43 +1916,22 @@ xml_parse(text *data, XmlOptionType xmloption_arg,
 							"could not allocate XML document");
 			doc->standalone = standalone;
 
-			root = xmlNewNode(NULL, (const xmlChar *) "content-root");
-			if (root == NULL || xmlerrcxt->err_occurred)
-				xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY,
-							"could not allocate xml node");
-
-			/*
-			 * This attaches root to doc, so we need not free it separately;
-			 * and there can't yet be any old root to free.
-			 */
-			oldroot = xmlDocSetRootElement(doc, root);
-			Assert(oldroot == NULL);
+			/* set parse options --- have to do this the ugly way */
+			save_keep_blanks = xmlKeepBlanksDefault(preserve_whitespace ? 1 : 0);
 
 			/* allow empty content */
 			if (*(utf8string + count))
 			{
-				xmlNodePtr	node_list = NULL;
-				xmlParserErrors res;
-
-				res = xmlParseInNodeContext(root,
-											(char *) utf8string + count,
-											strlen((char *) utf8string + count),
-											options,
-											&node_list);
-
-				if (res != XML_ERR_OK || xmlerrcxt->err_occurred)
+				res_code = xmlParseBalancedChunkMemory(doc, NULL, NULL, 0,
+													   utf8string + count,
+													   parsed_nodes);
+				if (res_code != 0 || xmlerrcxt->err_occurred)
 				{
-					xmlFreeNodeList(node_list);
 					xml_errsave(escontext, xmlerrcxt,
 								ERRCODE_INVALID_XML_CONTENT,
 								"invalid XML content");
 					goto fail;
 				}
-
-				if (parsed_nodes != NULL)
-					*parsed_nodes = node_list;
-				else
-					xmlFreeNodeList(node_list);
 			}
 		}
 
@@ -1917,6 +1940,8 @@ xml_parse(text *data, XmlOptionType xmloption_arg,
 	}
 	PG_CATCH();
 	{
+		if (save_keep_blanks != -1)
+			xmlKeepBlanksDefault(save_keep_blanks);
 		if (doc != NULL)
 			xmlFreeDoc(doc);
 		if (ctxt != NULL)
@@ -1928,6 +1953,9 @@ xml_parse(text *data, XmlOptionType xmloption_arg,
 	}
 	PG_END_TRY();
 
+	if (save_keep_blanks != -1)
+		xmlKeepBlanksDefault(save_keep_blanks);
+
 	if (ctxt != NULL)
 		xmlFreeParserCtxt(ctxt);
 
@@ -4220,20 +4248,27 @@ xml_xmlnodetoxmltype(xmlNodePtr cur, PgXmlErrorContext *xmlerrcxt)
 	}
 	else
 	{
-		xmlChar    *str;
+		volatile xmlChar *str = NULL;
 
-		str = xmlXPathCastNodeToString(cur);
 		PG_TRY();
 		{
+			char	   *escaped;
+
+			str = xmlXPathCastNodeToString(cur);
+			if (str == NULL || xmlerrcxt->err_occurred)
+				xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY,
+							"could not allocate xmlChar");
+
 			/* Here we rely on XML having the same representation as TEXT */
-			char	   *escaped = escape_xml((char *) str);
+			escaped = escape_xml((char *) str);
 
 			result = (xmltype *) cstring_to_text(escaped);
 			pfree(escaped);
 		}
 		PG_FINALLY();
 		{
-			xmlFree(str);
+			if (str)
+				xmlFree((xmlChar *) str);
 		}
 		PG_END_TRY();
 	}
diff --git a/src/backend/utils/cache/catcache.c b/src/backend/utils/cache/catcache.c
index 657648996c235..e2cd3feaf81d3 100644
--- a/src/backend/utils/cache/catcache.c
+++ b/src/backend/utils/cache/catcache.c
@@ -213,7 +213,7 @@ namehashfast(Datum datum)
 {
 	char	   *key = NameStr(*DatumGetName(datum));
 
-	return hash_any((unsigned char *) key, strlen(key));
+	return hash_bytes((unsigned char *) key, strlen(key));
 }
 
 static bool
@@ -317,6 +317,7 @@ GetCCHashEqFuncs(Oid keytype, CCHashFN *hashfunc, RegProcedure *eqfunc, CCFastEq
 		case REGDICTIONARYOID:
 		case REGROLEOID:
 		case REGNAMESPACEOID:
+		case REGDATABASEOID:
 			*hashfunc = int4hashfast;
 			*fasteqfunc = int4eqfast;
 			*eqfunc = F_OIDEQ;
diff --git a/src/backend/utils/cache/evtcache.c b/src/backend/utils/cache/evtcache.c
index ce596bf563856..b9d5a5998be50 100644
--- a/src/backend/utils/cache/evtcache.c
+++ b/src/backend/utils/cache/evtcache.c
@@ -78,7 +78,6 @@ BuildEventTriggerCache(void)
 {
 	HASHCTL		ctl;
 	HTAB	   *cache;
-	MemoryContext oldcontext;
 	Relation	rel;
 	Relation	irel;
 	SysScanDesc scan;
@@ -110,9 +109,6 @@ BuildEventTriggerCache(void)
 									  (Datum) 0);
 	}
 
-	/* Switch to correct memory context. */
-	oldcontext = MemoryContextSwitchTo(EventTriggerCacheContext);
-
 	/* Prevent the memory context from being nuked while we're rebuilding. */
 	EventTriggerCacheState = ETCS_REBUILD_STARTED;
 
@@ -145,6 +141,7 @@ BuildEventTriggerCache(void)
 		bool		evttags_isnull;
 		EventTriggerCacheEntry *entry;
 		bool		found;
+		MemoryContext oldcontext;
 
 		/* Get next tuple. */
 		tup = systable_getnext_ordered(scan, ForwardScanDirection);
@@ -171,6 +168,9 @@ BuildEventTriggerCache(void)
 		else
 			continue;
 
+		/* Switch to correct memory context. */
+		oldcontext = MemoryContextSwitchTo(EventTriggerCacheContext);
+
 		/* Allocate new cache item. */
 		item = palloc0(sizeof(EventTriggerCacheItem));
 		item->fnoid = form->evtfoid;
@@ -188,6 +188,9 @@ BuildEventTriggerCache(void)
 			entry->triggerlist = lappend(entry->triggerlist, item);
 		else
 			entry->triggerlist = list_make1(item);
+
+		/* Restore previous memory context. */
+		MemoryContextSwitchTo(oldcontext);
 	}
 
 	/* Done with pg_event_trigger scan. */
@@ -195,9 +198,6 @@ BuildEventTriggerCache(void)
 	index_close(irel, AccessShareLock);
 	relation_close(rel, AccessShareLock);
 
-	/* Restore previous memory context. */
-	MemoryContextSwitchTo(oldcontext);
-
 	/* Install new cache. */
 	EventTriggerCache = cache;
 
@@ -240,6 +240,8 @@ DecodeTextArrayToBitmapset(Datum array)
 	}
 
 	pfree(elems);
+	if ((Pointer) arr != DatumGetPointer(array))
+		pfree(arr);
 
 	return bms;
 }
diff --git a/src/backend/utils/cache/plancache.c b/src/backend/utils/cache/plancache.c
index 89a1c79e984d1..6661d2c6b7391 100644
--- a/src/backend/utils/cache/plancache.c
+++ b/src/backend/utils/cache/plancache.c
@@ -463,8 +463,7 @@ CompleteCachedPlan(CachedPlanSource *plansource,
 
 	/*
 	 * Save the final parameter types (or other parameter specification data)
-	 * into the source_context, as well as our other parameters.  Also save
-	 * the result tuple descriptor.
+	 * into the source_context, as well as our other parameters.
 	 */
 	MemoryContextSwitchTo(source_context);
 
@@ -480,9 +479,25 @@ CompleteCachedPlan(CachedPlanSource *plansource,
 	plansource->parserSetupArg = parserSetupArg;
 	plansource->cursor_options = cursor_options;
 	plansource->fixed_result = fixed_result;
-	plansource->resultDesc = PlanCacheComputeResultDesc(querytree_list);
 
+	/*
+	 * Also save the result tuple descriptor.  PlanCacheComputeResultDesc may
+	 * leak some cruft; normally we just accept that to save a copy step, but
+	 * in USE_VALGRIND mode be tidy by running it in the caller's context.
+	 */
+#ifdef USE_VALGRIND
+	MemoryContextSwitchTo(oldcxt);
+	plansource->resultDesc = PlanCacheComputeResultDesc(querytree_list);
+	if (plansource->resultDesc)
+	{
+		MemoryContextSwitchTo(source_context);
+		plansource->resultDesc = CreateTupleDescCopy(plansource->resultDesc);
+		MemoryContextSwitchTo(oldcxt);
+	}
+#else
+	plansource->resultDesc = PlanCacheComputeResultDesc(querytree_list);
 	MemoryContextSwitchTo(oldcxt);
+#endif
 
 	plansource->is_complete = true;
 	plansource->is_valid = true;
@@ -1283,6 +1298,7 @@ GetCachedPlan(CachedPlanSource *plansource, ParamListInfo boundParams,
 	CachedPlan *plan = NULL;
 	List	   *qlist;
 	bool		customplan;
+	ListCell   *lc;
 
 	/* Assert caller is doing things in a sane order */
 	Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
@@ -1385,6 +1401,13 @@ GetCachedPlan(CachedPlanSource *plansource, ParamListInfo boundParams,
 		plan->is_saved = true;
 	}
 
+	foreach(lc, plan->stmt_list)
+	{
+		PlannedStmt *pstmt = (PlannedStmt *) lfirst(lc);
+
+		pstmt->planOrigin = customplan ? PLAN_STMT_CACHE_CUSTOM : PLAN_STMT_CACHE_GENERIC;
+	}
+
 	return plan;
 }
 
diff --git a/src/backend/utils/cache/ts_cache.c b/src/backend/utils/cache/ts_cache.c
index 18cccd778fd8c..e8ae53238d07a 100644
--- a/src/backend/utils/cache/ts_cache.c
+++ b/src/backend/utils/cache/ts_cache.c
@@ -321,7 +321,9 @@ lookup_ts_dictionary_cache(Oid dictId)
 
 			/*
 			 * Init method runs in dictionary's private memory context, and we
-			 * make sure the options are stored there too
+			 * make sure the options are stored there too.  This typically
+			 * results in a small amount of memory leakage, but it's not worth
+			 * complicating the API for tmplinit functions to avoid it.
 			 */
 			oldcontext = MemoryContextSwitchTo(entry->dictCtx);
 
diff --git a/src/backend/utils/cache/typcache.c b/src/backend/utils/cache/typcache.c
index f9aec38a11fb3..6a347698edffe 100644
--- a/src/backend/utils/cache/typcache.c
+++ b/src/backend/utils/cache/typcache.c
@@ -1171,9 +1171,6 @@ load_domaintype_info(TypeCacheEntry *typentry)
 				elog(ERROR, "domain \"%s\" constraint \"%s\" has NULL conbin",
 					 NameStr(typTup->typname), NameStr(c->conname));
 
-			/* Convert conbin to C string in caller context */
-			constring = TextDatumGetCString(val);
-
 			/* Create the DomainConstraintCache object and context if needed */
 			if (dcc == NULL)
 			{
@@ -1189,9 +1186,8 @@ load_domaintype_info(TypeCacheEntry *typentry)
 				dcc->dccRefCount = 0;
 			}
 
-			/* Create node trees in DomainConstraintCache's context */
-			oldcxt = MemoryContextSwitchTo(dcc->dccContext);
-
+			/* Convert conbin to a node tree, still in caller's context */
+			constring = TextDatumGetCString(val);
 			check_expr = (Expr *) stringToNode(constring);
 
 			/*
@@ -1206,10 +1202,13 @@ load_domaintype_info(TypeCacheEntry *typentry)
 			 */
 			check_expr = expression_planner(check_expr);
 
+			/* Create only the minimally needed stuff in dccContext */
+			oldcxt = MemoryContextSwitchTo(dcc->dccContext);
+
 			r = makeNode(DomainConstraintState);
 			r->constrainttype = DOM_CONSTRAINT_CHECK;
 			r->name = pstrdup(NameStr(c->conname));
-			r->check_expr = check_expr;
+			r->check_expr = copyObject(check_expr);
 			r->check_exprstate = NULL;
 
 			MemoryContextSwitchTo(oldcxt);
diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index 47af743990fe9..afce1a8e1f003 100644
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -1128,12 +1128,15 @@ set_backtrace(ErrorData *edata, int num_skip)
 
 		nframes = backtrace(buf, lengthof(buf));
 		strfrms = backtrace_symbols(buf, nframes);
-		if (strfrms == NULL)
-			return;
-
-		for (int i = num_skip; i < nframes; i++)
-			appendStringInfo(&errtrace, "\n%s", strfrms[i]);
-		free(strfrms);
+		if (strfrms != NULL)
+		{
+			for (int i = num_skip; i < nframes; i++)
+				appendStringInfo(&errtrace, "\n%s", strfrms[i]);
+			free(strfrms);
+		}
+		else
+			appendStringInfoString(&errtrace,
+								   "insufficient memory for backtrace generation");
 	}
 #else
 	appendStringInfoString(&errtrace,
diff --git a/src/backend/utils/hash/dynahash.c b/src/backend/utils/hash/dynahash.c
index 1ad155d446e51..81da03629f0d2 100644
--- a/src/backend/utils/hash/dynahash.c
+++ b/src/backend/utils/hash/dynahash.c
@@ -22,10 +22,11 @@
  * lookup key's hash value as a partition number --- this will work because
  * of the way calc_bucket() maps hash values to bucket numbers.
  *
- * For hash tables in shared memory, the memory allocator function should
- * match malloc's semantics of returning NULL on failure.  For hash tables
- * in local memory, we typically use palloc() which will throw error on
- * failure.  The code in this file has to cope with both cases.
+ * The memory allocator function should match malloc's semantics of returning
+ * NULL on failure.  (This is essential for hash tables in shared memory.
+ * For hash tables in local memory, we used to use palloc() which will throw
+ * error on failure; but we no longer do, so it's untested whether this
+ * module will still cope with that behavior.)
  *
  * dynahash.c provides support for these types of lookup keys:
  *
@@ -98,6 +99,7 @@
 
 #include "access/xact.h"
 #include "common/hashfn.h"
+#include "lib/ilist.h"
 #include "port/pg_bitutils.h"
 #include "storage/shmem.h"
 #include "storage/spin.h"
@@ -195,6 +197,7 @@ struct HASHHDR
 	long		ssize;			/* segment size --- must be power of 2 */
 	int			sshift;			/* segment shift = log2(ssize) */
 	int			nelem_alloc;	/* number of entries to allocate at once */
+	bool		isfixed;		/* if true, don't enlarge */
 
 #ifdef HASH_STATISTICS
 
@@ -227,7 +230,6 @@ struct HTAB
 	MemoryContext hcxt;			/* memory context if default allocator used */
 	char	   *tabname;		/* table name (for error messages) */
 	bool		isshared;		/* true if table is in shared memory */
-	bool		isfixed;		/* if true, don't enlarge */
 
 	/* freezing a shared table isn't allowed, so we can keep state here */
 	bool		frozen;			/* true = no more inserts allowed */
@@ -236,6 +238,16 @@ struct HTAB
 	Size		keysize;		/* hash key length in bytes */
 	long		ssize;			/* segment size --- must be power of 2 */
 	int			sshift;			/* segment shift = log2(ssize) */
+
+	/*
+	 * In a USE_VALGRIND build, non-shared hashtables keep an slist chain of
+	 * all the element blocks they have allocated.  This pacifies Valgrind,
+	 * which would otherwise often claim that the element blocks are "possibly
+	 * lost" for lack of any non-interior pointers to their starts.
+	 */
+#ifdef USE_VALGRIND
+	slist_head	element_blocks;
+#endif
 };
 
 /*
@@ -618,8 +630,10 @@ hash_create(const char *tabname, long nelem, const HASHCTL *info, int flags)
 		}
 	}
 
+	/* Set isfixed if requested, but not till after we build initial entries */
 	if (flags & HASH_FIXED_SIZE)
-		hashp->isfixed = true;
+		hctl->isfixed = true;
+
 	return hashp;
 }
 
@@ -644,6 +658,8 @@ hdefault(HTAB *hashp)
 	hctl->ssize = DEF_SEGSIZE;
 	hctl->sshift = DEF_SEGSIZE_SHIFT;
 
+	hctl->isfixed = false;		/* can be enlarged */
+
 #ifdef HASH_STATISTICS
 	hctl->accesses = hctl->collisions = 0;
 #endif
@@ -1708,23 +1724,51 @@ element_alloc(HTAB *hashp, int nelem, int freelist_idx)
 {
 	HASHHDR    *hctl = hashp->hctl;
 	Size		elementSize;
+	Size		requestSize;
+	char	   *allocedBlock;
 	HASHELEMENT *firstElement;
 	HASHELEMENT *tmpElement;
 	HASHELEMENT *prevElement;
 	int			i;
 
-	if (hashp->isfixed)
+	if (hctl->isfixed)
 		return false;
 
 	/* Each element has a HASHELEMENT header plus user data. */
 	elementSize = MAXALIGN(sizeof(HASHELEMENT)) + MAXALIGN(hctl->entrysize);
 
+	requestSize = nelem * elementSize;
+
+	/* Add space for slist_node list link if we need one. */
+#ifdef USE_VALGRIND
+	if (!hashp->isshared)
+		requestSize += MAXALIGN(sizeof(slist_node));
+#endif
+
+	/* Allocate the memory. */
 	CurrentDynaHashCxt = hashp->hcxt;
-	firstElement = (HASHELEMENT *) hashp->alloc(nelem * elementSize);
+	allocedBlock = hashp->alloc(requestSize);
 
-	if (!firstElement)
+	if (!allocedBlock)
 		return false;
 
+	/*
+	 * If USE_VALGRIND, each allocated block of elements of a non-shared
+	 * hashtable is chained into a list, so that Valgrind won't think it's
+	 * been leaked.
+	 */
+#ifdef USE_VALGRIND
+	if (hashp->isshared)
+		firstElement = (HASHELEMENT *) allocedBlock;
+	else
+	{
+		slist_push_head(&hashp->element_blocks, (slist_node *) allocedBlock);
+		firstElement = (HASHELEMENT *) (allocedBlock + MAXALIGN(sizeof(slist_node)));
+	}
+#else
+	firstElement = (HASHELEMENT *) allocedBlock;
+#endif
+
 	/* prepare to link all the new entries into the freelist */
 	prevElement = NULL;
 	tmpElement = firstElement;
diff --git a/src/backend/utils/init/miscinit.c b/src/backend/utils/init/miscinit.c
index 43b4dbccc3de6..65d8cbfaed585 100644
--- a/src/backend/utils/init/miscinit.c
+++ b/src/backend/utils/init/miscinit.c
@@ -1183,7 +1183,6 @@ UnlinkLockFiles(int status, Datum arg)
 		/* Should we complain if the unlink fails? */
 	}
 	/* Since we're about to exit, no need to reclaim storage */
-	lock_files = NIL;
 
 	/*
 	 * Lock file removal should always be the last externally visible action
diff --git a/src/backend/utils/init/postinit.c b/src/backend/utils/init/postinit.c
index c86ceefda940b..641e535a73c7c 100644
--- a/src/backend/utils/init/postinit.c
+++ b/src/backend/utils/init/postinit.c
@@ -417,12 +417,11 @@ CheckMyDatabase(const char *name, bool am_superuser, bool override_allow_connect
 	datum = SysCacheGetAttrNotNull(DATABASEOID, tup, Anum_pg_database_datctype);
 	ctype = TextDatumGetCString(datum);
 
-	if (pg_perm_setlocale(LC_COLLATE, collate) == NULL)
-		ereport(FATAL,
-				(errmsg("database locale is incompatible with operating system"),
-				 errdetail("The database was initialized with LC_COLLATE \"%s\", "
-						   " which is not recognized by setlocale().", collate),
-				 errhint("Recreate the database with another locale or install the missing locale.")));
+	/*
+	 * Historcally, we set LC_COLLATE from datcollate, as well. That's no
+	 * longer necessary because all collation behavior is handled through
+	 * pg_locale_t.
+	 */
 
 	if (pg_perm_setlocale(LC_CTYPE, ctype) == NULL)
 		ereport(FATAL,
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 667df448732f2..e404c345e6eab 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -249,6 +249,7 @@ static void reapply_stacked_values(struct config_generic *variable,
 								   const char *curvalue,
 								   GucContext curscontext, GucSource cursource,
 								   Oid cursrole);
+static void free_placeholder(struct config_string *pHolder);
 static bool validate_option_array_item(const char *name, const char *value,
 									   bool skipIfNoPermissions);
 static void write_auto_conf_file(int fd, const char *filename, ConfigVariable *head);
@@ -4722,8 +4723,13 @@ AlterSystemSetConfigFile(AlterSystemStmt *altersysstmt)
 			 * the config file cannot cause postmaster start to fail, so we
 			 * don't have to be too tense about possibly installing a bad
 			 * value.)
+			 *
+			 * As an exception, we skip this check if this is a RESET command
+			 * for an unknown custom GUC, else there'd be no way for users to
+			 * remove such settings with reserved prefixes.
 			 */
-			(void) assignable_custom_variable_name(name, false, ERROR);
+			if (value || !valid_custom_variable_name(name))
+				(void) assignable_custom_variable_name(name, false, ERROR);
 		}
 
 		/*
@@ -5018,16 +5024,8 @@ define_custom_variable(struct config_generic *variable)
 		set_config_sourcefile(name, pHolder->gen.sourcefile,
 							  pHolder->gen.sourceline);
 
-	/*
-	 * Free up as much as we conveniently can of the placeholder structure.
-	 * (This neglects any stack items, so it's possible for some memory to be
-	 * leaked.  Since this can only happen once per session per variable, it
-	 * doesn't seem worth spending much code on.)
-	 */
-	set_string_field(pHolder, pHolder->variable, NULL);
-	set_string_field(pHolder, &pHolder->reset_val, NULL);
-
-	guc_free(pHolder);
+	/* Now we can free the no-longer-referenced placeholder variable */
+	free_placeholder(pHolder);
 }
 
 /*
@@ -5126,6 +5124,25 @@ reapply_stacked_values(struct config_generic *variable,
 	}
 }
 
+/*
+ * Free up a no-longer-referenced placeholder GUC variable.
+ *
+ * This neglects any stack items, so it's possible for some memory to be
+ * leaked.  Since this can only happen once per session per variable, it
+ * doesn't seem worth spending much code on.
+ */
+static void
+free_placeholder(struct config_string *pHolder)
+{
+	/* Placeholders are always STRING type, so free their values */
+	Assert(pHolder->gen.vartype == PGC_STRING);
+	set_string_field(pHolder, pHolder->variable, NULL);
+	set_string_field(pHolder, &pHolder->reset_val, NULL);
+
+	guc_free(unconstify(char *, pHolder->gen.name));
+	guc_free(pHolder);
+}
+
 /*
  * Functions for extensions to call to define their custom GUC variables.
  */
@@ -5286,9 +5303,7 @@ MarkGUCPrefixReserved(const char *className)
 
 	/*
 	 * Check for existing placeholders.  We must actually remove invalid
-	 * placeholders, else future parallel worker startups will fail.  (We
-	 * don't bother trying to free associated memory, since this shouldn't
-	 * happen often.)
+	 * placeholders, else future parallel worker startups will fail.
 	 */
 	hash_seq_init(&status, guc_hashtab);
 	while ((hentry = (GUCHashEntry *) hash_seq_search(&status)) != NULL)
@@ -5312,6 +5327,8 @@ MarkGUCPrefixReserved(const char *className)
 						NULL);
 			/* Remove it from any lists it's in, too */
 			RemoveGUCFromLists(var);
+			/* And free it */
+			free_placeholder((struct config_string *) var);
 		}
 	}
 
@@ -6711,6 +6728,7 @@ validate_option_array_item(const char *name, const char *value,
 
 {
 	struct config_generic *gconf;
+	bool		reset_custom;
 
 	/*
 	 * There are three cases to consider:
@@ -6729,16 +6747,21 @@ validate_option_array_item(const char *name, const char *value,
 	 * it's assumed to be fully validated.)
 	 *
 	 * name is not known and can't be created as a placeholder.  Throw error,
-	 * unless skipIfNoPermissions is true, in which case return false.
+	 * unless skipIfNoPermissions or reset_custom is true.  If reset_custom is
+	 * true, this is a RESET or RESET ALL operation for an unknown custom GUC
+	 * with a reserved prefix, in which case we want to fall through to the
+	 * placeholder case described in the preceding paragraph (else there'd be
+	 * no way for users to remove them).  Otherwise, return false.
 	 */
-	gconf = find_option(name, true, skipIfNoPermissions, ERROR);
-	if (!gconf)
+	reset_custom = (!value && valid_custom_variable_name(name));
+	gconf = find_option(name, true, skipIfNoPermissions || reset_custom, ERROR);
+	if (!gconf && !reset_custom)
 	{
 		/* not known, failed to make a placeholder */
 		return false;
 	}
 
-	if (gconf->flags & GUC_CUSTOM_PLACEHOLDER)
+	if (!gconf || gconf->flags & GUC_CUSTOM_PLACEHOLDER)
 	{
 		/*
 		 * We cannot do any meaningful check on the value, so only permissions
diff --git a/src/backend/utils/misc/guc_tables.c b/src/backend/utils/misc/guc_tables.c
index 511dc32d51921..d14b1678e7fec 100644
--- a/src/backend/utils/misc/guc_tables.c
+++ b/src/backend/utils/misc/guc_tables.c
@@ -3081,7 +3081,7 @@ struct config_int ConfigureNamesInt[] =
 		},
 		&max_slot_wal_keep_size_mb,
 		-1, -1, MAX_KILOBYTES,
-		check_max_slot_wal_keep_size, NULL, NULL
+		NULL, NULL, NULL
 	},
 
 	{
@@ -3100,11 +3100,11 @@ struct config_int ConfigureNamesInt[] =
 			gettext_noop("Sets the duration a replication slot can remain idle before "
 						 "it is invalidated."),
 			NULL,
-			GUC_UNIT_MIN
+			GUC_UNIT_S
 		},
-		&idle_replication_slot_timeout_mins,
-		0, 0, INT_MAX / SECS_PER_MINUTE,
-		check_idle_replication_slot_timeout, NULL, NULL
+		&idle_replication_slot_timeout_secs,
+		0, 0, INT_MAX,
+		NULL, NULL, NULL
 	},
 
 	{
diff --git a/src/backend/utils/misc/injection_point.c b/src/backend/utils/misc/injection_point.c
index f58ebc8ee522d..83b887b697807 100644
--- a/src/backend/utils/misc/injection_point.c
+++ b/src/backend/utils/misc/injection_point.c
@@ -584,3 +584,49 @@ IsInjectionPointAttached(const char *name)
 	return false;				/* silence compiler */
 #endif
 }
+
+/*
+ * Retrieve a list of all the injection points currently attached.
+ *
+ * This list is palloc'd in the current memory context.
+ */
+List *
+InjectionPointList(void)
+{
+#ifdef USE_INJECTION_POINTS
+	List	   *inj_points = NIL;
+	uint32		max_inuse;
+
+	LWLockAcquire(InjectionPointLock, LW_SHARED);
+
+	max_inuse = pg_atomic_read_u32(&ActiveInjectionPoints->max_inuse);
+
+	for (uint32 idx = 0; idx < max_inuse; idx++)
+	{
+		InjectionPointEntry *entry;
+		InjectionPointData *inj_point;
+		uint64		generation;
+
+		entry = &ActiveInjectionPoints->entries[idx];
+		generation = pg_atomic_read_u64(&entry->generation);
+
+		/* skip free slots */
+		if (generation % 2 == 0)
+			continue;
+
+		inj_point = (InjectionPointData *) palloc0(sizeof(InjectionPointData));
+		inj_point->name = pstrdup(entry->name);
+		inj_point->library = pstrdup(entry->library);
+		inj_point->function = pstrdup(entry->function);
+		inj_points = lappend(inj_points, inj_point);
+	}
+
+	LWLockRelease(InjectionPointLock);
+
+	return inj_points;
+
+#else
+	elog(ERROR, "Injection points are not supported by this build");
+	return NIL;					/* keep compiler quiet */
+#endif
+}
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index 341f88adc87b2..a9d8293474af5 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -342,7 +342,7 @@
 				# (change requires restart)
 #wal_keep_size = 0		# in megabytes; 0 disables
 #max_slot_wal_keep_size = -1	# in megabytes; -1 disables
-#idle_replication_slot_timeout = 0	# in minutes; 0 disables
+#idle_replication_slot_timeout = 0	# in seconds; 0 disables
 #wal_sender_timeout = 60s	# in milliseconds; 0 disables
 #track_commit_timestamp = off	# collect timestamp of transaction commit
 				# (change requires restart)
diff --git a/src/backend/utils/misc/ps_status.c b/src/backend/utils/misc/ps_status.c
index e08b26e8c14f2..4df25944deb33 100644
--- a/src/backend/utils/misc/ps_status.c
+++ b/src/backend/utils/misc/ps_status.c
@@ -100,6 +100,17 @@ static void flush_ps_display(void);
 static int	save_argc;
 static char **save_argv;
 
+/*
+ * Valgrind seems not to consider the global "environ" variable as a valid
+ * root pointer; so when we allocate a new environment array, it claims that
+ * data is leaked.  To fix that, keep our own statically-allocated copy of the
+ * pointer.  (Oddly, this doesn't seem to be a problem for "argv".)
+ */
+#if defined(PS_USE_CLOBBER_ARGV) && defined(USE_VALGRIND)
+extern char **ps_status_new_environ;
+char	  **ps_status_new_environ;
+#endif
+
 
 /*
  * Call this early in startup to save the original argc/argv values.
@@ -206,6 +217,11 @@ save_ps_display_args(int argc, char **argv)
 		}
 		new_environ[i] = NULL;
 		environ = new_environ;
+
+		/* See notes about Valgrind above. */
+#ifdef USE_VALGRIND
+		ps_status_new_environ = new_environ;
+#endif
 	}
 
 	/*
diff --git a/src/backend/utils/mmgr/alignedalloc.c b/src/backend/utils/mmgr/alignedalloc.c
index 7eea695de62c5..b1be742691497 100644
--- a/src/backend/utils/mmgr/alignedalloc.c
+++ b/src/backend/utils/mmgr/alignedalloc.c
@@ -45,6 +45,15 @@ AlignedAllocFree(void *pointer)
 			 GetMemoryChunkContext(unaligned)->name, chunk);
 #endif
 
+	/*
+	 * Create a dummy vchunk covering the start of the unaligned chunk, but
+	 * not overlapping the aligned chunk.  This will be freed while pfree'ing
+	 * the unaligned chunk, keeping Valgrind happy.  Then when we return to
+	 * the outer pfree, that will clean up the vchunk for the aligned chunk.
+	 */
+	VALGRIND_MEMPOOL_ALLOC(GetMemoryChunkContext(unaligned), unaligned,
+						   (char *) pointer - (char *) unaligned);
+
 	/* Recursively pfree the unaligned chunk */
 	pfree(unaligned);
 }
@@ -123,6 +132,15 @@ AlignedAllocRealloc(void *pointer, Size size, int flags)
 	VALGRIND_MAKE_MEM_DEFINED(pointer, old_size);
 	memcpy(newptr, pointer, Min(size, old_size));
 
+	/*
+	 * Create a dummy vchunk covering the start of the old unaligned chunk,
+	 * but not overlapping the aligned chunk.  This will be freed while
+	 * pfree'ing the old unaligned chunk, keeping Valgrind happy.  Then when
+	 * we return to repalloc, it will move the vchunk for the aligned chunk.
+	 */
+	VALGRIND_MEMPOOL_ALLOC(ctx, unaligned,
+						   (char *) pointer - (char *) unaligned);
+
 	pfree(unaligned);
 
 	return newptr;
diff --git a/src/backend/utils/mmgr/aset.c b/src/backend/utils/mmgr/aset.c
index 666ecd8f78d0e..9ef109ca586bd 100644
--- a/src/backend/utils/mmgr/aset.c
+++ b/src/backend/utils/mmgr/aset.c
@@ -103,6 +103,8 @@
 
 #define ALLOC_BLOCKHDRSZ	MAXALIGN(sizeof(AllocBlockData))
 #define ALLOC_CHUNKHDRSZ	sizeof(MemoryChunk)
+#define FIRST_BLOCKHDRSZ	(MAXALIGN(sizeof(AllocSetContext)) + \
+							 ALLOC_BLOCKHDRSZ)
 
 typedef struct AllocBlockData *AllocBlock;	/* forward reference */
 
@@ -458,6 +460,21 @@ AllocSetContextCreateInternal(MemoryContext parent,
 	 * we'd leak the header/initial block if we ereport in this stretch.
 	 */
 
+	/* Create a vpool associated with the context */
+	VALGRIND_CREATE_MEMPOOL(set, 0, false);
+
+	/*
+	 * Create a vchunk covering both the AllocSetContext struct and the keeper
+	 * block's header.  (Perhaps it would be more sensible for these to be two
+	 * separate vchunks, but doing that seems to tickle bugs in some versions
+	 * of Valgrind.)  We must have these vchunks, and also a vchunk for each
+	 * subsequently-added block header, so that Valgrind considers the
+	 * pointers within them while checking for leaked memory.  Note that
+	 * Valgrind doesn't distinguish between these vchunks and those created by
+	 * mcxt.c for the user-accessible-data chunks we allocate.
+	 */
+	VALGRIND_MEMPOOL_ALLOC(set, set, FIRST_BLOCKHDRSZ);
+
 	/* Fill in the initial block's block header */
 	block = KeeperBlock(set);
 	block->aset = set;
@@ -585,6 +602,14 @@ AllocSetReset(MemoryContext context)
 #ifdef CLOBBER_FREED_MEMORY
 			wipe_mem(block, block->freeptr - ((char *) block));
 #endif
+
+			/*
+			 * We need to free the block header's vchunk explicitly, although
+			 * the user-data vchunks within will go away in the TRIM below.
+			 * Otherwise Valgrind complains about leaked allocations.
+			 */
+			VALGRIND_MEMPOOL_FREE(set, block);
+
 			free(block);
 		}
 		block = next;
@@ -592,6 +617,14 @@ AllocSetReset(MemoryContext context)
 
 	Assert(context->mem_allocated == keepersize);
 
+	/*
+	 * Instruct Valgrind to throw away all the vchunks associated with this
+	 * context, except for the one covering the AllocSetContext and
+	 * keeper-block header.  This gets rid of the vchunks for whatever user
+	 * data is getting discarded by the context reset.
+	 */
+	VALGRIND_MEMPOOL_TRIM(set, set, FIRST_BLOCKHDRSZ);
+
 	/* Reset block size allocation sequence, too */
 	set->nextBlockSize = set->initBlockSize;
 }
@@ -648,6 +681,9 @@ AllocSetDelete(MemoryContext context)
 				freelist->first_free = (AllocSetContext *) oldset->header.nextchild;
 				freelist->num_free--;
 
+				/* Destroy the context's vpool --- see notes below */
+				VALGRIND_DESTROY_MEMPOOL(oldset);
+
 				/* All that remains is to free the header/initial block */
 				free(oldset);
 			}
@@ -675,13 +711,24 @@ AllocSetDelete(MemoryContext context)
 #endif
 
 		if (!IsKeeperBlock(set, block))
+		{
+			/* As in AllocSetReset, free block-header vchunks explicitly */
+			VALGRIND_MEMPOOL_FREE(set, block);
 			free(block);
+		}
 
 		block = next;
 	}
 
 	Assert(context->mem_allocated == keepersize);
 
+	/*
+	 * Destroy the vpool.  We don't seem to need to explicitly free the
+	 * initial block's header vchunk, nor any user-data vchunks that Valgrind
+	 * still knows about; they'll all go away automatically.
+	 */
+	VALGRIND_DESTROY_MEMPOOL(set);
+
 	/* Finally, free the context header, including the keeper block */
 	free(set);
 }
@@ -716,6 +763,9 @@ AllocSetAllocLarge(MemoryContext context, Size size, int flags)
 	if (block == NULL)
 		return MemoryContextAllocationFailure(context, size, flags);
 
+	/* Make a vchunk covering the new block's header */
+	VALGRIND_MEMPOOL_ALLOC(set, block, ALLOC_BLOCKHDRSZ);
+
 	context->mem_allocated += blksize;
 
 	block->aset = set;
@@ -922,6 +972,9 @@ AllocSetAllocFromNewBlock(MemoryContext context, Size size, int flags,
 	if (block == NULL)
 		return MemoryContextAllocationFailure(context, size, flags);
 
+	/* Make a vchunk covering the new block's header */
+	VALGRIND_MEMPOOL_ALLOC(set, block, ALLOC_BLOCKHDRSZ);
+
 	context->mem_allocated += blksize;
 
 	block->aset = set;
@@ -1104,6 +1157,10 @@ AllocSetFree(void *pointer)
 #ifdef CLOBBER_FREED_MEMORY
 		wipe_mem(block, block->freeptr - ((char *) block));
 #endif
+
+		/* As in AllocSetReset, free block-header vchunks explicitly */
+		VALGRIND_MEMPOOL_FREE(set, block);
+
 		free(block);
 	}
 	else
@@ -1184,6 +1241,7 @@ AllocSetRealloc(void *pointer, Size size, int flags)
 		 * realloc() to make the containing block bigger, or smaller, with
 		 * minimum space wastage.
 		 */
+		AllocBlock	newblock;
 		Size		chksize;
 		Size		blksize;
 		Size		oldblksize;
@@ -1223,14 +1281,21 @@ AllocSetRealloc(void *pointer, Size size, int flags)
 		blksize = chksize + ALLOC_BLOCKHDRSZ + ALLOC_CHUNKHDRSZ;
 		oldblksize = block->endptr - ((char *) block);
 
-		block = (AllocBlock) realloc(block, blksize);
-		if (block == NULL)
+		newblock = (AllocBlock) realloc(block, blksize);
+		if (newblock == NULL)
 		{
 			/* Disallow access to the chunk header. */
 			VALGRIND_MAKE_MEM_NOACCESS(chunk, ALLOC_CHUNKHDRSZ);
 			return MemoryContextAllocationFailure(&set->header, size, flags);
 		}
 
+		/*
+		 * Move the block-header vchunk explicitly.  (mcxt.c will take care of
+		 * moving the vchunk for the user data.)
+		 */
+		VALGRIND_MEMPOOL_CHANGE(set, block, newblock, ALLOC_BLOCKHDRSZ);
+		block = newblock;
+
 		/* updated separately, not to underflow when (oldblksize > blksize) */
 		set->header.mem_allocated -= oldblksize;
 		set->header.mem_allocated += blksize;
@@ -1294,7 +1359,7 @@ AllocSetRealloc(void *pointer, Size size, int flags)
 		/* Ensure any padding bytes are marked NOACCESS. */
 		VALGRIND_MAKE_MEM_NOACCESS((char *) pointer + size, chksize - size);
 
-		/* Disallow access to the chunk header . */
+		/* Disallow access to the chunk header. */
 		VALGRIND_MAKE_MEM_NOACCESS(chunk, ALLOC_CHUNKHDRSZ);
 
 		return pointer;
diff --git a/src/backend/utils/mmgr/bump.c b/src/backend/utils/mmgr/bump.c
index f7a37d1b3e86c..2805d55a2eca9 100644
--- a/src/backend/utils/mmgr/bump.c
+++ b/src/backend/utils/mmgr/bump.c
@@ -45,7 +45,9 @@
 #include "utils/memutils_memorychunk.h"
 #include "utils/memutils_internal.h"
 
-#define Bump_BLOCKHDRSZ	MAXALIGN(sizeof(BumpBlock))
+#define Bump_BLOCKHDRSZ		MAXALIGN(sizeof(BumpBlock))
+#define FIRST_BLOCKHDRSZ	(MAXALIGN(sizeof(BumpContext)) + \
+							 Bump_BLOCKHDRSZ)
 
 /* No chunk header unless built with MEMORY_CONTEXT_CHECKING */
 #ifdef MEMORY_CONTEXT_CHECKING
@@ -189,6 +191,12 @@ BumpContextCreate(MemoryContext parent, const char *name, Size minContextSize,
 	 * Avoid writing code that can fail between here and MemoryContextCreate;
 	 * we'd leak the header and initial block if we ereport in this stretch.
 	 */
+
+	/* See comments about Valgrind interactions in aset.c */
+	VALGRIND_CREATE_MEMPOOL(set, 0, false);
+	/* This vchunk covers the BumpContext and the keeper block header */
+	VALGRIND_MEMPOOL_ALLOC(set, set, FIRST_BLOCKHDRSZ);
+
 	dlist_init(&set->blocks);
 
 	/* Fill in the initial block's block header */
@@ -262,6 +270,14 @@ BumpReset(MemoryContext context)
 			BumpBlockFree(set, block);
 	}
 
+	/*
+	 * Instruct Valgrind to throw away all the vchunks associated with this
+	 * context, except for the one covering the BumpContext and keeper-block
+	 * header.  This gets rid of the vchunks for whatever user data is getting
+	 * discarded by the context reset.
+	 */
+	VALGRIND_MEMPOOL_TRIM(set, set, FIRST_BLOCKHDRSZ);
+
 	/* Reset block size allocation sequence, too */
 	set->nextBlockSize = set->initBlockSize;
 
@@ -279,6 +295,10 @@ BumpDelete(MemoryContext context)
 {
 	/* Reset to release all releasable BumpBlocks */
 	BumpReset(context);
+
+	/* Destroy the vpool -- see notes in aset.c */
+	VALGRIND_DESTROY_MEMPOOL(context);
+
 	/* And free the context header and keeper block */
 	free(context);
 }
@@ -318,6 +338,9 @@ BumpAllocLarge(MemoryContext context, Size size, int flags)
 	if (block == NULL)
 		return MemoryContextAllocationFailure(context, size, flags);
 
+	/* Make a vchunk covering the new block's header */
+	VALGRIND_MEMPOOL_ALLOC(set, block, Bump_BLOCKHDRSZ);
+
 	context->mem_allocated += blksize;
 
 	/* the block is completely full */
@@ -455,6 +478,9 @@ BumpAllocFromNewBlock(MemoryContext context, Size size, int flags,
 	if (block == NULL)
 		return MemoryContextAllocationFailure(context, size, flags);
 
+	/* Make a vchunk covering the new block's header */
+	VALGRIND_MEMPOOL_ALLOC(set, block, Bump_BLOCKHDRSZ);
+
 	context->mem_allocated += blksize;
 
 	/* initialize the new block */
@@ -606,6 +632,9 @@ BumpBlockFree(BumpContext *set, BumpBlock *block)
 	wipe_mem(block, ((char *) block->endptr - (char *) block));
 #endif
 
+	/* As in aset.c, free block-header vchunks explicitly */
+	VALGRIND_MEMPOOL_FREE(set, block);
+
 	free(block);
 }
 
diff --git a/src/backend/utils/mmgr/dsa.c b/src/backend/utils/mmgr/dsa.c
index 17d4f7a7a06e1..be43e9351c3d3 100644
--- a/src/backend/utils/mmgr/dsa.c
+++ b/src/backend/utils/mmgr/dsa.c
@@ -531,6 +531,21 @@ dsa_attach(dsa_handle handle)
 	return area;
 }
 
+/*
+ * Returns whether the area with the given handle was already attached by the
+ * current process.  The area must have been created with dsa_create (not
+ * dsa_create_in_place).
+ */
+bool
+dsa_is_attached(dsa_handle handle)
+{
+	/*
+	 * An area handle is really a DSM segment handle for the first segment, so
+	 * we can just search for that.
+	 */
+	return dsm_find_mapping(handle) != NULL;
+}
+
 /*
  * Attach to an area that was created with dsa_create_in_place.  The caller
  * must somehow know the location in memory that was used when the area was
diff --git a/src/backend/utils/mmgr/generation.c b/src/backend/utils/mmgr/generation.c
index 18679ad4f1e41..cfafc9bf0829d 100644
--- a/src/backend/utils/mmgr/generation.c
+++ b/src/backend/utils/mmgr/generation.c
@@ -45,6 +45,8 @@
 
 #define Generation_BLOCKHDRSZ	MAXALIGN(sizeof(GenerationBlock))
 #define Generation_CHUNKHDRSZ	sizeof(MemoryChunk)
+#define FIRST_BLOCKHDRSZ		(MAXALIGN(sizeof(GenerationContext)) + \
+								 Generation_BLOCKHDRSZ)
 
 #define Generation_CHUNK_FRACTION	8
 
@@ -221,6 +223,12 @@ GenerationContextCreate(MemoryContext parent,
 	 * Avoid writing code that can fail between here and MemoryContextCreate;
 	 * we'd leak the header if we ereport in this stretch.
 	 */
+
+	/* See comments about Valgrind interactions in aset.c */
+	VALGRIND_CREATE_MEMPOOL(set, 0, false);
+	/* This vchunk covers the GenerationContext and the keeper block header */
+	VALGRIND_MEMPOOL_ALLOC(set, set, FIRST_BLOCKHDRSZ);
+
 	dlist_init(&set->blocks);
 
 	/* Fill in the initial block's block header */
@@ -309,6 +317,14 @@ GenerationReset(MemoryContext context)
 			GenerationBlockFree(set, block);
 	}
 
+	/*
+	 * Instruct Valgrind to throw away all the vchunks associated with this
+	 * context, except for the one covering the GenerationContext and
+	 * keeper-block header.  This gets rid of the vchunks for whatever user
+	 * data is getting discarded by the context reset.
+	 */
+	VALGRIND_MEMPOOL_TRIM(set, set, FIRST_BLOCKHDRSZ);
+
 	/* set it so new allocations to make use of the keeper block */
 	set->block = KeeperBlock(set);
 
@@ -329,6 +345,10 @@ GenerationDelete(MemoryContext context)
 {
 	/* Reset to release all releasable GenerationBlocks */
 	GenerationReset(context);
+
+	/* Destroy the vpool -- see notes in aset.c */
+	VALGRIND_DESTROY_MEMPOOL(context);
+
 	/* And free the context header and keeper block */
 	free(context);
 }
@@ -365,6 +385,9 @@ GenerationAllocLarge(MemoryContext context, Size size, int flags)
 	if (block == NULL)
 		return MemoryContextAllocationFailure(context, size, flags);
 
+	/* Make a vchunk covering the new block's header */
+	VALGRIND_MEMPOOL_ALLOC(set, block, Generation_BLOCKHDRSZ);
+
 	context->mem_allocated += blksize;
 
 	/* block with a single (used) chunk */
@@ -487,6 +510,9 @@ GenerationAllocFromNewBlock(MemoryContext context, Size size, int flags,
 	if (block == NULL)
 		return MemoryContextAllocationFailure(context, size, flags);
 
+	/* Make a vchunk covering the new block's header */
+	VALGRIND_MEMPOOL_ALLOC(set, block, Generation_BLOCKHDRSZ);
+
 	context->mem_allocated += blksize;
 
 	/* initialize the new block */
@@ -677,6 +703,9 @@ GenerationBlockFree(GenerationContext *set, GenerationBlock *block)
 	wipe_mem(block, block->blksize);
 #endif
 
+	/* As in aset.c, free block-header vchunks explicitly */
+	VALGRIND_MEMPOOL_FREE(set, block);
+
 	free(block);
 }
 
diff --git a/src/backend/utils/mmgr/mcxt.c b/src/backend/utils/mmgr/mcxt.c
index 15fa4d0a55eeb..47fd774c7d280 100644
--- a/src/backend/utils/mmgr/mcxt.c
+++ b/src/backend/utils/mmgr/mcxt.c
@@ -8,6 +8,23 @@
  * context-type-specific operations via the function pointers in a
  * context's MemoryContextMethods struct.
  *
+ * A note about Valgrind support: when USE_VALGRIND is defined, we provide
+ * support for memory leak tracking at the allocation-unit level.  Valgrind
+ * does leak detection by tracking allocated "chunks", which can be grouped
+ * into "pools".  The "chunk" terminology is overloaded, since we use that
+ * word for our allocation units, and it's sometimes important to distinguish
+ * those from the Valgrind objects that describe them.  To reduce confusion,
+ * let's use the terms "vchunk" and "vpool" for the Valgrind objects.
+ *
+ * We use a separate vpool for each memory context.  The context-type-specific
+ * code is responsible for creating and deleting the vpools, and also for
+ * creating vchunks to cover its management data structures such as block
+ * headers.  (There must be a vchunk that includes every pointer we want
+ * Valgrind to consider for leak-tracking purposes.)  This module creates
+ * and deletes the vchunks that cover the caller-visible allocated chunks.
+ * However, the context-type-specific code must handle cleaning up those
+ * vchunks too during memory context reset operations.
+ *
  *
  * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
@@ -418,8 +435,6 @@ MemoryContextResetOnly(MemoryContext context)
 
 		context->methods->reset(context);
 		context->isReset = true;
-		VALGRIND_DESTROY_MEMPOOL(context);
-		VALGRIND_CREATE_MEMPOOL(context, 0, false);
 	}
 }
 
@@ -526,8 +541,6 @@ MemoryContextDeleteOnly(MemoryContext context)
 	context->ident = NULL;
 
 	context->methods->delete_context(context);
-
-	VALGRIND_DESTROY_MEMPOOL(context);
 }
 
 /*
@@ -560,9 +573,7 @@ MemoryContextDeleteChildren(MemoryContext context)
  * the specified context, since that means it will automatically be freed
  * when no longer needed.
  *
- * There is no API for deregistering a callback once registered.  If you
- * want it to not do anything anymore, adjust the state pointed to by its
- * "arg" to indicate that.
+ * Note that callers can assume this cannot fail.
  */
 void
 MemoryContextRegisterResetCallback(MemoryContext context,
@@ -577,6 +588,41 @@ MemoryContextRegisterResetCallback(MemoryContext context,
 	context->isReset = false;
 }
 
+/*
+ * MemoryContextUnregisterResetCallback
+ *		Undo the effects of MemoryContextRegisterResetCallback.
+ *
+ * This can be used if a callback's effects are no longer required
+ * at some point before the context has been reset/deleted.  It is the
+ * caller's responsibility to pfree the callback struct (if needed).
+ *
+ * An assertion failure occurs if the callback was not registered.
+ * We could alternatively define that case as a no-op, but that seems too
+ * likely to mask programming errors such as passing the wrong context.
+ */
+void
+MemoryContextUnregisterResetCallback(MemoryContext context,
+									 MemoryContextCallback *cb)
+{
+	MemoryContextCallback *prev,
+			   *cur;
+
+	Assert(MemoryContextIsValid(context));
+
+	for (prev = NULL, cur = context->reset_cbs; cur != NULL;
+		 prev = cur, cur = cur->next)
+	{
+		if (cur != cb)
+			continue;
+		if (prev)
+			prev->next = cur->next;
+		else
+			context->reset_cbs = cur->next;
+		return;
+	}
+	Assert(false);
+}
+
 /*
  * MemoryContextCallResetCallbacks
  *		Internal function to call all registered callbacks for context.
@@ -1137,8 +1183,6 @@ MemoryContextCreate(MemoryContext node,
 		node->nextchild = NULL;
 		node->allowInCritSection = false;
 	}
-
-	VALGRIND_CREATE_MEMPOOL(node, 0, false);
 }
 
 /*
@@ -1421,7 +1465,13 @@ MemoryContextAllocAligned(MemoryContext context,
 	void	   *unaligned;
 	void	   *aligned;
 
-	/* wouldn't make much sense to waste that much space */
+	/*
+	 * Restrict alignto to ensure that it can fit into the "value" field of
+	 * the redirection MemoryChunk, and that the distance back to the start of
+	 * the unaligned chunk will fit into the space available for that.  This
+	 * isn't a limitation in practice, since it wouldn't make much sense to
+	 * waste that much space.
+	 */
 	Assert(alignto < (128 * 1024 * 1024));
 
 	/* ensure alignto is a power of 2 */
@@ -1458,10 +1508,15 @@ MemoryContextAllocAligned(MemoryContext context,
 	alloc_size += 1;
 #endif
 
-	/* perform the actual allocation */
-	unaligned = MemoryContextAllocExtended(context, alloc_size, flags);
+	/*
+	 * Perform the actual allocation, but do not pass down MCXT_ALLOC_ZERO.
+	 * This ensures that wasted bytes beyond the aligned chunk do not become
+	 * DEFINED.
+	 */
+	unaligned = MemoryContextAllocExtended(context, alloc_size,
+										   flags & ~MCXT_ALLOC_ZERO);
 
-	/* set the aligned pointer */
+	/* compute the aligned pointer */
 	aligned = (void *) TYPEALIGN(alignto, (char *) unaligned +
 								 sizeof(MemoryChunk));
 
@@ -1489,12 +1544,23 @@ MemoryContextAllocAligned(MemoryContext context,
 	set_sentinel(aligned, size);
 #endif
 
-	/* Mark the bytes before the redirection header as noaccess */
-	VALGRIND_MAKE_MEM_NOACCESS(unaligned,
-							   (char *) alignedchunk - (char *) unaligned);
+	/*
+	 * MemoryContextAllocExtended marked the whole unaligned chunk as a
+	 * vchunk.  Undo that, instead making just the aligned chunk be a vchunk.
+	 * This prevents Valgrind from complaining that the vchunk is possibly
+	 * leaked, since only pointers to the aligned chunk will exist.
+	 *
+	 * After these calls, the aligned chunk will be marked UNDEFINED, and all
+	 * the rest of the unaligned chunk (the redirection chunk header, the
+	 * padding bytes before it, and any wasted trailing bytes) will be marked
+	 * NOACCESS, which is what we want.
+	 */
+	VALGRIND_MEMPOOL_FREE(context, unaligned);
+	VALGRIND_MEMPOOL_ALLOC(context, aligned, size);
 
-	/* Disallow access to the redirection chunk header. */
-	VALGRIND_MAKE_MEM_NOACCESS(alignedchunk, sizeof(MemoryChunk));
+	/* Now zero (and make DEFINED) just the aligned chunk, if requested */
+	if ((flags & MCXT_ALLOC_ZERO) != 0)
+		MemSetAligned(aligned, 0, size);
 
 	return aligned;
 }
@@ -1528,16 +1594,12 @@ void
 pfree(void *pointer)
 {
 #ifdef USE_VALGRIND
-	MemoryContextMethodID method = GetMemoryChunkMethodID(pointer);
 	MemoryContext context = GetMemoryChunkContext(pointer);
 #endif
 
 	MCXT_METHOD(pointer, free_p) (pointer);
 
-#ifdef USE_VALGRIND
-	if (method != MCTX_ALIGNED_REDIRECT_ID)
-		VALGRIND_MEMPOOL_FREE(context, pointer);
-#endif
+	VALGRIND_MEMPOOL_FREE(context, pointer);
 }
 
 /*
@@ -1547,9 +1609,6 @@ pfree(void *pointer)
 void *
 repalloc(void *pointer, Size size)
 {
-#ifdef USE_VALGRIND
-	MemoryContextMethodID method = GetMemoryChunkMethodID(pointer);
-#endif
 #if defined(USE_ASSERT_CHECKING) || defined(USE_VALGRIND)
 	MemoryContext context = GetMemoryChunkContext(pointer);
 #endif
@@ -1572,10 +1631,7 @@ repalloc(void *pointer, Size size)
 	 */
 	ret = MCXT_METHOD(pointer, realloc) (pointer, size, 0);
 
-#ifdef USE_VALGRIND
-	if (method != MCTX_ALIGNED_REDIRECT_ID)
-		VALGRIND_MEMPOOL_CHANGE(context, pointer, ret, size);
-#endif
+	VALGRIND_MEMPOOL_CHANGE(context, pointer, ret, size);
 
 	return ret;
 }
diff --git a/src/backend/utils/mmgr/slab.c b/src/backend/utils/mmgr/slab.c
index d32c0d318fbf4..0e35abcf5a055 100644
--- a/src/backend/utils/mmgr/slab.c
+++ b/src/backend/utils/mmgr/slab.c
@@ -377,6 +377,11 @@ SlabContextCreate(MemoryContext parent,
 	 * we'd leak the header if we ereport in this stretch.
 	 */
 
+	/* See comments about Valgrind interactions in aset.c */
+	VALGRIND_CREATE_MEMPOOL(slab, 0, false);
+	/* This vchunk covers the SlabContext only */
+	VALGRIND_MEMPOOL_ALLOC(slab, slab, sizeof(SlabContext));
+
 	/* Fill in SlabContext-specific header fields */
 	slab->chunkSize = (uint32) chunkSize;
 	slab->fullChunkSize = (uint32) fullChunkSize;
@@ -451,6 +456,10 @@ SlabReset(MemoryContext context)
 #ifdef CLOBBER_FREED_MEMORY
 		wipe_mem(block, slab->blockSize);
 #endif
+
+		/* As in aset.c, free block-header vchunks explicitly */
+		VALGRIND_MEMPOOL_FREE(slab, block);
+
 		free(block);
 		context->mem_allocated -= slab->blockSize;
 	}
@@ -467,11 +476,23 @@ SlabReset(MemoryContext context)
 #ifdef CLOBBER_FREED_MEMORY
 			wipe_mem(block, slab->blockSize);
 #endif
+
+			/* As in aset.c, free block-header vchunks explicitly */
+			VALGRIND_MEMPOOL_FREE(slab, block);
+
 			free(block);
 			context->mem_allocated -= slab->blockSize;
 		}
 	}
 
+	/*
+	 * Instruct Valgrind to throw away all the vchunks associated with this
+	 * context, except for the one covering the SlabContext.  This gets rid of
+	 * the vchunks for whatever user data is getting discarded by the context
+	 * reset.
+	 */
+	VALGRIND_MEMPOOL_TRIM(slab, slab, sizeof(SlabContext));
+
 	slab->curBlocklistIndex = 0;
 
 	Assert(context->mem_allocated == 0);
@@ -486,6 +507,10 @@ SlabDelete(MemoryContext context)
 {
 	/* Reset to release all the SlabBlocks */
 	SlabReset(context);
+
+	/* Destroy the vpool -- see notes in aset.c */
+	VALGRIND_DESTROY_MEMPOOL(context);
+
 	/* And free the context header */
 	free(context);
 }
@@ -567,6 +592,9 @@ SlabAllocFromNewBlock(MemoryContext context, Size size, int flags)
 		if (unlikely(block == NULL))
 			return MemoryContextAllocationFailure(context, size, flags);
 
+		/* Make a vchunk covering the new block's header */
+		VALGRIND_MEMPOOL_ALLOC(slab, block, Slab_BLOCKHDRSZ);
+
 		block->slab = slab;
 		context->mem_allocated += slab->blockSize;
 
@@ -795,6 +823,10 @@ SlabFree(void *pointer)
 #ifdef CLOBBER_FREED_MEMORY
 			wipe_mem(block, slab->blockSize);
 #endif
+
+			/* As in aset.c, free block-header vchunks explicitly */
+			VALGRIND_MEMPOOL_FREE(slab, block);
+
 			free(block);
 			slab->header.mem_allocated -= slab->blockSize;
 		}
diff --git a/src/bin/initdb/Makefile b/src/bin/initdb/Makefile
index 997e0a013e956..c0470efda92a3 100644
--- a/src/bin/initdb/Makefile
+++ b/src/bin/initdb/Makefile
@@ -20,7 +20,7 @@ include $(top_builddir)/src/Makefile.global
 # from libpq, else we have risks of version skew if we run with a libpq
 # shared library from a different PG version.  Define
 # USE_PRIVATE_ENCODING_FUNCS to ensure that that happens.
-override CPPFLAGS := -DUSE_PRIVATE_ENCODING_FUNCS -I$(libpq_srcdir) -I$(top_srcdir)/src/timezone $(ICU_CFLAGS) $(CPPFLAGS)
+override CPPFLAGS := -DUSE_PRIVATE_ENCODING_FUNCS -I$(libpq_srcdir) -I$(top_srcdir)/src/timezone $(CPPFLAGS) $(ICU_CFLAGS)
 
 # We need libpq only because fe_utils does.
 LDFLAGS_INTERNAL += -L$(top_builddir)/src/fe_utils -lpgfeutils $(libpq_pgport) $(ICU_LIBS)
diff --git a/src/bin/pg_amcheck/t/004_verify_heapam.pl b/src/bin/pg_amcheck/t/004_verify_heapam.pl
index 2a3af2666f52a..72693660fb64b 100644
--- a/src/bin/pg_amcheck/t/004_verify_heapam.pl
+++ b/src/bin/pg_amcheck/t/004_verify_heapam.pl
@@ -529,7 +529,7 @@ sub header
 		$tup->{t_infomask2} |= HEAP_NATTS_MASK;
 
 		push @expected,
-		  qr/${$header}number of attributes 2047 exceeds maximum expected for table 3/;
+		  qr/${$header}number of attributes 2047 exceeds maximum 3 expected for table/;
 	}
 	elsif ($offnum == 10)
 	{
@@ -552,7 +552,7 @@ sub header
 		$tup->{t_hoff} = 32;
 
 		push @expected,
-		  qr/${$header}number of attributes 67 exceeds maximum expected for table 3/;
+		  qr/${$header}number of attributes 67 exceeds maximum 3 expected for table/;
 	}
 	elsif ($offnum == 12)
 	{
diff --git a/src/bin/pg_basebackup/meson.build b/src/bin/pg_basebackup/meson.build
index 8a1c96b4f5c84..3a7fc10eab02f 100644
--- a/src/bin/pg_basebackup/meson.build
+++ b/src/bin/pg_basebackup/meson.build
@@ -93,9 +93,9 @@ tests += {
   'sd': meson.current_source_dir(),
   'bd': meson.current_build_dir(),
   'tap': {
-    'env': {'GZIP_PROGRAM': gzip.found() ? gzip.path() : '',
-            'TAR': tar.found() ? tar.path() : '',
-            'LZ4': program_lz4.found() ? program_lz4.path() : '',
+    'env': {'GZIP_PROGRAM': gzip.found() ? gzip.full_path() : '',
+            'TAR': tar.found() ? tar.full_path() : '',
+            'LZ4': program_lz4.found() ? program_lz4.full_path() : '',
     },
     'tests': [
       't/010_pg_basebackup.pl',
diff --git a/src/bin/pg_basebackup/pg_basebackup.c b/src/bin/pg_basebackup/pg_basebackup.c
index eb7354200bcee..55621f35fb6b7 100644
--- a/src/bin/pg_basebackup/pg_basebackup.c
+++ b/src/bin/pg_basebackup/pg_basebackup.c
@@ -487,7 +487,7 @@ reached_end_position(XLogRecPtr segendpos, uint32 timeline,
 			if (r < 0)
 				pg_fatal("could not read from ready pipe: %m");
 
-			if (sscanf(xlogend, "%X/%X", &hi, &lo) != 2)
+			if (sscanf(xlogend, "%X/%08X", &hi, &lo) != 2)
 				pg_fatal("could not parse write-ahead log location \"%s\"",
 						 xlogend);
 			xlogendptr = ((uint64) hi) << 32 | lo;
@@ -629,7 +629,7 @@ StartLogStreamer(char *startpos, uint32 timeline, char *sysidentifier,
 	param->wal_compress_level = wal_compress_level;
 
 	/* Convert the starting position */
-	if (sscanf(startpos, "%X/%X", &hi, &lo) != 2)
+	if (sscanf(startpos, "%X/%08X", &hi, &lo) != 2)
 		pg_fatal("could not parse write-ahead log location \"%s\"",
 				 startpos);
 	param->startptr = ((uint64) hi) << 32 | lo;
@@ -2255,7 +2255,7 @@ BaseBackup(char *compression_algorithm, char *compression_detail,
 		 * value directly in the variable, and then set the flag that says
 		 * it's there.
 		 */
-		if (sscanf(xlogend, "%X/%X", &hi, &lo) != 2)
+		if (sscanf(xlogend, "%X/%08X", &hi, &lo) != 2)
 			pg_fatal("could not parse write-ahead log location \"%s\"",
 					 xlogend);
 		xlogendptr = ((uint64) hi) << 32 | lo;
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 11f71c0380181..3986882f04292 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -1250,8 +1250,17 @@ setup_recovery(const struct LogicalRepInfo *dbinfo, const char *datadir, const c
 	appendPQExpBufferStr(recoveryconfcontents, "recovery_target = ''\n");
 	appendPQExpBufferStr(recoveryconfcontents,
 						 "recovery_target_timeline = 'latest'\n");
+
+	/*
+	 * Set recovery_target_inclusive = false to avoid reapplying the
+	 * transaction committed at 'lsn' after subscription is enabled. This is
+	 * because the provided 'lsn' is also used as the replication start point
+	 * for the subscription. So, the server can send the transaction committed
+	 * at that 'lsn' after replication is started which can lead to applying
+	 * the same transaction twice if we keep recovery_target_inclusive = true.
+	 */
 	appendPQExpBufferStr(recoveryconfcontents,
-						 "recovery_target_inclusive = true\n");
+						 "recovery_target_inclusive = false\n");
 	appendPQExpBufferStr(recoveryconfcontents,
 						 "recovery_target_action = promote\n");
 	appendPQExpBufferStr(recoveryconfcontents, "recovery_target_name = ''\n");
@@ -1262,7 +1271,7 @@ setup_recovery(const struct LogicalRepInfo *dbinfo, const char *datadir, const c
 	{
 		appendPQExpBufferStr(recoveryconfcontents, "# dry run mode");
 		appendPQExpBuffer(recoveryconfcontents,
-						  "recovery_target_lsn = '%X/%X'\n",
+						  "recovery_target_lsn = '%X/%08X'\n",
 						  LSN_FORMAT_ARGS((XLogRecPtr) InvalidXLogRecPtr));
 	}
 	else
@@ -1876,7 +1885,7 @@ set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo, cons
 	if (dry_run)
 	{
 		suboid = InvalidOid;
-		lsnstr = psprintf("%X/%X", LSN_FORMAT_ARGS((XLogRecPtr) InvalidXLogRecPtr));
+		lsnstr = psprintf("%X/%08X", LSN_FORMAT_ARGS((XLogRecPtr) InvalidXLogRecPtr));
 	}
 	else
 	{
diff --git a/src/bin/pg_basebackup/pg_receivewal.c b/src/bin/pg_basebackup/pg_receivewal.c
index e816cf58101fb..289ca14dcfe58 100644
--- a/src/bin/pg_basebackup/pg_receivewal.c
+++ b/src/bin/pg_basebackup/pg_receivewal.c
@@ -188,14 +188,14 @@ stop_streaming(XLogRecPtr xlogpos, uint32 timeline, bool segment_finished)
 
 	/* we assume that we get called once at the end of each segment */
 	if (verbose && segment_finished)
-		pg_log_info("finished segment at %X/%X (timeline %u)",
+		pg_log_info("finished segment at %X/%08X (timeline %u)",
 					LSN_FORMAT_ARGS(xlogpos),
 					timeline);
 
 	if (!XLogRecPtrIsInvalid(endpos) && endpos < xlogpos)
 	{
 		if (verbose)
-			pg_log_info("stopped log streaming at %X/%X (timeline %u)",
+			pg_log_info("stopped log streaming at %X/%08X (timeline %u)",
 						LSN_FORMAT_ARGS(xlogpos),
 						timeline);
 		time_to_stop = true;
@@ -211,7 +211,7 @@ stop_streaming(XLogRecPtr xlogpos, uint32 timeline, bool segment_finished)
 	 * timeline, but it's close enough for reporting purposes.
 	 */
 	if (verbose && prevtimeline != 0 && prevtimeline != timeline)
-		pg_log_info("switched to timeline %u at %X/%X",
+		pg_log_info("switched to timeline %u at %X/%08X",
 					timeline,
 					LSN_FORMAT_ARGS(prevpos));
 
@@ -575,7 +575,7 @@ StreamLog(void)
 	 * Start the replication
 	 */
 	if (verbose)
-		pg_log_info("starting log streaming at %X/%X (timeline %u)",
+		pg_log_info("starting log streaming at %X/%08X (timeline %u)",
 					LSN_FORMAT_ARGS(stream.startpos),
 					stream.timeline);
 
@@ -689,7 +689,7 @@ main(int argc, char **argv)
 				basedir = pg_strdup(optarg);
 				break;
 			case 'E':
-				if (sscanf(optarg, "%X/%X", &hi, &lo) != 2)
+				if (sscanf(optarg, "%X/%08X", &hi, &lo) != 2)
 					pg_fatal("could not parse end position \"%s\"", optarg);
 				endpos = ((uint64) hi) << 32 | lo;
 				break;
diff --git a/src/bin/pg_basebackup/pg_recvlogical.c b/src/bin/pg_basebackup/pg_recvlogical.c
index fb7a6a1d05d8d..0e9d2e2394731 100644
--- a/src/bin/pg_basebackup/pg_recvlogical.c
+++ b/src/bin/pg_basebackup/pg_recvlogical.c
@@ -144,7 +144,7 @@ sendFeedback(PGconn *conn, TimestampTz now, bool force, bool replyRequested)
 		return true;
 
 	if (verbose)
-		pg_log_info("confirming write up to %X/%X, flush to %X/%X (slot %s)",
+		pg_log_info("confirming write up to %X/%08X, flush to %X/%08X (slot %s)",
 					LSN_FORMAT_ARGS(output_written_lsn),
 					LSN_FORMAT_ARGS(output_fsync_lsn),
 					replication_slot);
@@ -238,13 +238,13 @@ StreamLogicalLog(void)
 	 * Start the replication
 	 */
 	if (verbose)
-		pg_log_info("starting log streaming at %X/%X (slot %s)",
+		pg_log_info("starting log streaming at %X/%08X (slot %s)",
 					LSN_FORMAT_ARGS(startpos),
 					replication_slot);
 
 	/* Initiate the replication stream at specified location */
 	query = createPQExpBuffer();
-	appendPQExpBuffer(query, "START_REPLICATION SLOT \"%s\" LOGICAL %X/%X",
+	appendPQExpBuffer(query, "START_REPLICATION SLOT \"%s\" LOGICAL %X/%08X",
 					  replication_slot, LSN_FORMAT_ARGS(startpos));
 
 	/* print options if there are any */
@@ -517,7 +517,7 @@ StreamLogicalLog(void)
 		}
 
 		/*
-		 * Read the header of the XLogData message, enclosed in the CopyData
+		 * Read the header of the WALData message, enclosed in the CopyData
 		 * message. We only need the WAL location field (dataStart), the rest
 		 * of the header is ignored.
 		 */
@@ -605,7 +605,7 @@ StreamLogicalLog(void)
 		/*
 		 * We're doing a client-initiated clean exit and have sent CopyDone to
 		 * the server. Drain any messages, so we don't miss a last-minute
-		 * ErrorResponse. The walsender stops generating XLogData records once
+		 * ErrorResponse. The walsender stops generating WALData records once
 		 * it sees CopyDone, so expect this to finish quickly. After CopyDone,
 		 * it's too late for sendFeedback(), even if this were to take a long
 		 * time. Hence, use synchronous-mode PQgetCopyData().
@@ -800,12 +800,12 @@ main(int argc, char **argv)
 				break;
 /* replication options */
 			case 'I':
-				if (sscanf(optarg, "%X/%X", &hi, &lo) != 2)
+				if (sscanf(optarg, "%X/%08X", &hi, &lo) != 2)
 					pg_fatal("could not parse start position \"%s\"", optarg);
 				startpos = ((uint64) hi) << 32 | lo;
 				break;
 			case 'E':
-				if (sscanf(optarg, "%X/%X", &hi, &lo) != 2)
+				if (sscanf(optarg, "%X/%08X", &hi, &lo) != 2)
 					pg_fatal("could not parse end position \"%s\"", optarg);
 				endpos = ((uint64) hi) << 32 | lo;
 				break;
@@ -1075,12 +1075,12 @@ prepareToTerminate(PGconn *conn, XLogRecPtr endpos, StreamStopReason reason,
 				pg_log_info("received interrupt signal, exiting");
 				break;
 			case STREAM_STOP_KEEPALIVE:
-				pg_log_info("end position %X/%X reached by keepalive",
+				pg_log_info("end position %X/%08X reached by keepalive",
 							LSN_FORMAT_ARGS(endpos));
 				break;
 			case STREAM_STOP_END_OF_WAL:
 				Assert(!XLogRecPtrIsInvalid(lsn));
-				pg_log_info("end position %X/%X reached by WAL record at %X/%X",
+				pg_log_info("end position %X/%08X reached by WAL record at %X/%08X",
 							LSN_FORMAT_ARGS(endpos), LSN_FORMAT_ARGS(lsn));
 				break;
 			case STREAM_STOP_NONE:
diff --git a/src/bin/pg_basebackup/receivelog.c b/src/bin/pg_basebackup/receivelog.c
index 6b6e32dfbdf56..f2b54d3c50171 100644
--- a/src/bin/pg_basebackup/receivelog.c
+++ b/src/bin/pg_basebackup/receivelog.c
@@ -38,8 +38,8 @@ static int	CopyStreamReceive(PGconn *conn, long timeout, pgsocket stop_socket,
 							  char **buffer);
 static bool ProcessKeepaliveMsg(PGconn *conn, StreamCtl *stream, char *copybuf,
 								int len, XLogRecPtr blockpos, TimestampTz *last_status);
-static bool ProcessXLogDataMsg(PGconn *conn, StreamCtl *stream, char *copybuf, int len,
-							   XLogRecPtr *blockpos);
+static bool ProcessWALDataMsg(PGconn *conn, StreamCtl *stream, char *copybuf, int len,
+							  XLogRecPtr *blockpos);
 static PGresult *HandleEndOfCopyStream(PGconn *conn, StreamCtl *stream, char *copybuf,
 									   XLogRecPtr blockpos, XLogRecPtr *stoppos);
 static bool CheckCopyStreamStop(PGconn *conn, StreamCtl *stream, XLogRecPtr blockpos);
@@ -571,7 +571,7 @@ ReceiveXlogStream(PGconn *conn, StreamCtl *stream)
 			return true;
 
 		/* Initiate the replication stream at specified location */
-		snprintf(query, sizeof(query), "START_REPLICATION %s%X/%X TIMELINE %u",
+		snprintf(query, sizeof(query), "START_REPLICATION %s%X/%08X TIMELINE %u",
 				 slotcmd,
 				 LSN_FORMAT_ARGS(stream->startpos),
 				 stream->timeline);
@@ -628,7 +628,7 @@ ReceiveXlogStream(PGconn *conn, StreamCtl *stream)
 			}
 			if (stream->startpos > stoppos)
 			{
-				pg_log_error("server stopped streaming timeline %u at %X/%X, but reported next timeline %u to begin at %X/%X",
+				pg_log_error("server stopped streaming timeline %u at %X/%08X, but reported next timeline %u to begin at %X/%08X",
 							 stream->timeline, LSN_FORMAT_ARGS(stoppos),
 							 newtimeline, LSN_FORMAT_ARGS(stream->startpos));
 				goto error;
@@ -720,7 +720,7 @@ ReadEndOfStreamingResult(PGresult *res, XLogRecPtr *startpos, uint32 *timeline)
 	}
 
 	*timeline = atoi(PQgetvalue(res, 0, 0));
-	if (sscanf(PQgetvalue(res, 0, 1), "%X/%X", &startpos_xlogid,
+	if (sscanf(PQgetvalue(res, 0, 1), "%X/%08X", &startpos_xlogid,
 			   &startpos_xrecoff) != 2)
 	{
 		pg_log_error("could not parse next timeline's starting point \"%s\"",
@@ -831,7 +831,7 @@ HandleCopyStream(PGconn *conn, StreamCtl *stream,
 			}
 			else if (copybuf[0] == 'w')
 			{
-				if (!ProcessXLogDataMsg(conn, stream, copybuf, r, &blockpos))
+				if (!ProcessWALDataMsg(conn, stream, copybuf, r, &blockpos))
 					goto error;
 
 				/*
@@ -1041,11 +1041,11 @@ ProcessKeepaliveMsg(PGconn *conn, StreamCtl *stream, char *copybuf, int len,
 }
 
 /*
- * Process XLogData message.
+ * Process WALData message.
  */
 static bool
-ProcessXLogDataMsg(PGconn *conn, StreamCtl *stream, char *copybuf, int len,
-				   XLogRecPtr *blockpos)
+ProcessWALDataMsg(PGconn *conn, StreamCtl *stream, char *copybuf, int len,
+				  XLogRecPtr *blockpos)
 {
 	int			xlogoff;
 	int			bytes_left;
@@ -1054,13 +1054,13 @@ ProcessXLogDataMsg(PGconn *conn, StreamCtl *stream, char *copybuf, int len,
 
 	/*
 	 * Once we've decided we don't want to receive any more, just ignore any
-	 * subsequent XLogData messages.
+	 * subsequent WALData messages.
 	 */
 	if (!(still_sending))
 		return true;
 
 	/*
-	 * Read the header of the XLogData message, enclosed in the CopyData
+	 * Read the header of the WALData message, enclosed in the CopyData
 	 * message. We only need the WAL location field (dataStart), the rest of
 	 * the header is ignored.
 	 */
@@ -1162,7 +1162,7 @@ ProcessXLogDataMsg(PGconn *conn, StreamCtl *stream, char *copybuf, int len,
 					return false;
 				}
 				still_sending = false;
-				return true;	/* ignore the rest of this XLogData packet */
+				return true;	/* ignore the rest of this WALData packet */
 			}
 		}
 	}
diff --git a/src/bin/pg_basebackup/streamutil.c b/src/bin/pg_basebackup/streamutil.c
index c7b8a4c3a4b6a..e5a7cb6e5b14e 100644
--- a/src/bin/pg_basebackup/streamutil.c
+++ b/src/bin/pg_basebackup/streamutil.c
@@ -445,7 +445,7 @@ RunIdentifySystem(PGconn *conn, char **sysid, TimeLineID *starttli,
 	/* Get LSN start position if necessary */
 	if (startpos != NULL)
 	{
-		if (sscanf(PQgetvalue(res, 0, 2), "%X/%X", &hi, &lo) != 2)
+		if (sscanf(PQgetvalue(res, 0, 2), "%X/%08X", &hi, &lo) != 2)
 		{
 			pg_log_error("could not parse write-ahead log location \"%s\"",
 						 PQgetvalue(res, 0, 2));
@@ -551,7 +551,7 @@ GetSlotInformation(PGconn *conn, const char *slot_name,
 		uint32		hi,
 					lo;
 
-		if (sscanf(PQgetvalue(res, 0, 1), "%X/%X", &hi, &lo) != 2)
+		if (sscanf(PQgetvalue(res, 0, 1), "%X/%08X", &hi, &lo) != 2)
 		{
 			pg_log_error("could not parse restart_lsn \"%s\" for replication slot \"%s\"",
 						 PQgetvalue(res, 0, 1), slot_name);
diff --git a/src/bin/pg_combinebackup/backup_label.c b/src/bin/pg_combinebackup/backup_label.c
index e89d4603f09dc..e774bc78a6264 100644
--- a/src/bin/pg_combinebackup/backup_label.c
+++ b/src/bin/pg_combinebackup/backup_label.c
@@ -247,7 +247,7 @@ parse_lsn(char *s, char *e, XLogRecPtr *lsn, char **c)
 	unsigned	lo;
 
 	*e = '\0';
-	success = (sscanf(s, "%X/%X%n", &hi, &lo, &nchars) == 2);
+	success = (sscanf(s, "%X/%08X%n", &hi, &lo, &nchars) == 2);
 	*e = save;
 
 	if (success)
diff --git a/src/bin/pg_combinebackup/pg_combinebackup.c b/src/bin/pg_combinebackup/pg_combinebackup.c
index 28e58cd8ef458..f5cef99f62730 100644
--- a/src/bin/pg_combinebackup/pg_combinebackup.c
+++ b/src/bin/pg_combinebackup/pg_combinebackup.c
@@ -569,7 +569,7 @@ check_backup_label_files(int n_backups, char **backup_dirs)
 			pg_fatal("backup at \"%s\" starts on timeline %u, but expected %u",
 					 backup_dirs[i], start_tli, check_tli);
 		if (i < n_backups - 1 && start_lsn != check_lsn)
-			pg_fatal("backup at \"%s\" starts at LSN %X/%X, but expected %X/%X",
+			pg_fatal("backup at \"%s\" starts at LSN %X/%08X, but expected %X/%08X",
 					 backup_dirs[i],
 					 LSN_FORMAT_ARGS(start_lsn),
 					 LSN_FORMAT_ARGS(check_lsn));
diff --git a/src/bin/pg_combinebackup/write_manifest.c b/src/bin/pg_combinebackup/write_manifest.c
index 313f8929df509..819a3fd0b7a6b 100644
--- a/src/bin/pg_combinebackup/write_manifest.c
+++ b/src/bin/pg_combinebackup/write_manifest.c
@@ -155,7 +155,7 @@ finalize_manifest(manifest_writer *mwriter,
 	for (wal_range = first_wal_range; wal_range != NULL;
 		 wal_range = wal_range->next)
 		appendStringInfo(&mwriter->buf,
-						 "%s{ \"Timeline\": %u, \"Start-LSN\": \"%X/%X\", \"End-LSN\": \"%X/%X\" }",
+						 "%s{ \"Timeline\": %u, \"Start-LSN\": \"%X/%08X\", \"End-LSN\": \"%X/%08X\" }",
 						 wal_range == first_wal_range ? "" : ",\n",
 						 wal_range->tli,
 						 LSN_FORMAT_ARGS(wal_range->start_lsn),
diff --git a/src/bin/pg_controldata/pg_controldata.c b/src/bin/pg_controldata/pg_controldata.c
index 7bb801bb88612..10de058ce91f4 100644
--- a/src/bin/pg_controldata/pg_controldata.c
+++ b/src/bin/pg_controldata/pg_controldata.c
@@ -245,9 +245,9 @@ main(int argc, char *argv[])
 		   dbState(ControlFile->state));
 	printf(_("pg_control last modified:             %s\n"),
 		   pgctime_str);
-	printf(_("Latest checkpoint location:           %X/%X\n"),
+	printf(_("Latest checkpoint location:           %X/%08X\n"),
 		   LSN_FORMAT_ARGS(ControlFile->checkPoint));
-	printf(_("Latest checkpoint's REDO location:    %X/%X\n"),
+	printf(_("Latest checkpoint's REDO location:    %X/%08X\n"),
 		   LSN_FORMAT_ARGS(ControlFile->checkPointCopy.redo));
 	printf(_("Latest checkpoint's REDO WAL file:    %s\n"),
 		   xlogfilename);
@@ -282,15 +282,15 @@ main(int argc, char *argv[])
 		   ControlFile->checkPointCopy.newestCommitTsXid);
 	printf(_("Time of latest checkpoint:            %s\n"),
 		   ckpttime_str);
-	printf(_("Fake LSN counter for unlogged rels:   %X/%X\n"),
+	printf(_("Fake LSN counter for unlogged rels:   %X/%08X\n"),
 		   LSN_FORMAT_ARGS(ControlFile->unloggedLSN));
-	printf(_("Minimum recovery ending location:     %X/%X\n"),
+	printf(_("Minimum recovery ending location:     %X/%08X\n"),
 		   LSN_FORMAT_ARGS(ControlFile->minRecoveryPoint));
 	printf(_("Min recovery ending loc's timeline:   %u\n"),
 		   ControlFile->minRecoveryPointTLI);
-	printf(_("Backup start location:                %X/%X\n"),
+	printf(_("Backup start location:                %X/%08X\n"),
 		   LSN_FORMAT_ARGS(ControlFile->backupStartPoint));
-	printf(_("Backup end location:                  %X/%X\n"),
+	printf(_("Backup end location:                  %X/%08X\n"),
 		   LSN_FORMAT_ARGS(ControlFile->backupEndPoint));
 	printf(_("End-of-backup record required:        %s\n"),
 		   ControlFile->backupEndRequired ? _("yes") : _("no"));
diff --git a/src/bin/pg_dump/common.c b/src/bin/pg_dump/common.c
index aa1589e3331d2..a1976fae607d6 100644
--- a/src/bin/pg_dump/common.c
+++ b/src/bin/pg_dump/common.c
@@ -17,6 +17,7 @@
 
 #include <ctype.h>
 
+#include "catalog/pg_am_d.h"
 #include "catalog/pg_class_d.h"
 #include "catalog/pg_collation_d.h"
 #include "catalog/pg_extension_d.h"
@@ -944,6 +945,24 @@ findOprByOid(Oid oid)
 	return (OprInfo *) dobj;
 }
 
+/*
+ * findAccessMethodByOid
+ *	  finds the DumpableObject for the access method with the given oid
+ *	  returns NULL if not found
+ */
+AccessMethodInfo *
+findAccessMethodByOid(Oid oid)
+{
+	CatalogId	catId;
+	DumpableObject *dobj;
+
+	catId.tableoid = AccessMethodRelationId;
+	catId.oid = oid;
+	dobj = findObjectByCatalogId(catId);
+	Assert(dobj == NULL || dobj->objType == DO_ACCESS_METHOD);
+	return (AccessMethodInfo *) dobj;
+}
+
 /*
  * findCollationByOid
  *	  finds the DumpableObject for the collation with the given oid
diff --git a/src/bin/pg_dump/meson.build b/src/bin/pg_dump/meson.build
index d8e9e101254b1..a2233b0a1b431 100644
--- a/src/bin/pg_dump/meson.build
+++ b/src/bin/pg_dump/meson.build
@@ -91,9 +91,9 @@ tests += {
   'bd': meson.current_build_dir(),
   'tap': {
     'env': {
-      'GZIP_PROGRAM': gzip.found() ? gzip.path() : '',
-      'LZ4': program_lz4.found() ? program_lz4.path() : '',
-      'ZSTD': program_zstd.found() ? program_zstd.path() : '',
+      'GZIP_PROGRAM': gzip.found() ? gzip.full_path() : '',
+      'LZ4': program_lz4.found() ? program_lz4.full_path() : '',
+      'ZSTD': program_zstd.found() ? program_zstd.full_path() : '',
       'with_icu': icu.found() ? 'yes' : 'no',
     },
     'tests': [
@@ -102,7 +102,6 @@ tests += {
       't/003_pg_dump_with_server.pl',
       't/004_pg_dump_parallel.pl',
       't/005_pg_dump_filterfile.pl',
-      't/006_pg_dumpall.pl',
       't/010_dump_connstr.pl',
     ],
   },
diff --git a/src/bin/pg_dump/parallel.c b/src/bin/pg_dump/parallel.c
index 5974d6706fd57..086adcdc50295 100644
--- a/src/bin/pg_dump/parallel.c
+++ b/src/bin/pg_dump/parallel.c
@@ -333,16 +333,6 @@ on_exit_close_archive(Archive *AHX)
 	on_exit_nicely(archive_close_connection, &shutdown_info);
 }
 
-/*
- * When pg_restore restores multiple databases, then update already added entry
- * into array for cleanup.
- */
-void
-replace_on_exit_close_archive(Archive *AHX)
-{
-	shutdown_info.AHX = AHX;
-}
-
 /*
  * on_exit_nicely handler for shutting down database connections and
  * worker processes cleanly.
diff --git a/src/bin/pg_dump/pg_backup.h b/src/bin/pg_dump/pg_backup.h
index af0007fb6d2f1..4ebef1e864451 100644
--- a/src/bin/pg_dump/pg_backup.h
+++ b/src/bin/pg_dump/pg_backup.h
@@ -308,7 +308,7 @@ extern void SetArchiveOptions(Archive *AH, DumpOptions *dopt, RestoreOptions *ro
 
 extern void ProcessArchiveRestoreOptions(Archive *AHX);
 
-extern void RestoreArchive(Archive *AHX, bool append_data);
+extern void RestoreArchive(Archive *AHX);
 
 /* Open an existing archive */
 extern Archive *OpenArchive(const char *FileSpec, const ArchiveFormat fmt);
diff --git a/src/bin/pg_dump/pg_backup_archiver.c b/src/bin/pg_dump/pg_backup_archiver.c
index 197c1295d93fd..dce88f040ace3 100644
--- a/src/bin/pg_dump/pg_backup_archiver.c
+++ b/src/bin/pg_dump/pg_backup_archiver.c
@@ -31,6 +31,8 @@
 #endif
 
 #include "catalog/pg_class_d.h"
+#include "catalog/pg_largeobject_metadata_d.h"
+#include "catalog/pg_shdepend_d.h"
 #include "common/string.h"
 #include "compress_io.h"
 #include "dumputils.h"
@@ -85,7 +87,7 @@ static int	RestoringToDB(ArchiveHandle *AH);
 static void dump_lo_buf(ArchiveHandle *AH);
 static void dumpTimestamp(ArchiveHandle *AH, const char *msg, time_t tim);
 static void SetOutput(ArchiveHandle *AH, const char *filename,
-					  const pg_compress_specification compression_spec, bool append_data);
+					  const pg_compress_specification compression_spec);
 static CompressFileHandle *SaveOutput(ArchiveHandle *AH);
 static void RestoreOutput(ArchiveHandle *AH, CompressFileHandle *savedOutput);
 
@@ -337,14 +339,9 @@ ProcessArchiveRestoreOptions(Archive *AHX)
 		StrictNamesCheck(ropt);
 }
 
-/*
- * RestoreArchive
- *
- * If append_data is set, then append data into file as we are restoring dump
- * of multiple databases which was taken by pg_dumpall.
- */
+/* Public */
 void
-RestoreArchive(Archive *AHX, bool append_data)
+RestoreArchive(Archive *AHX)
 {
 	ArchiveHandle *AH = (ArchiveHandle *) AHX;
 	RestoreOptions *ropt = AH->public.ropt;
@@ -461,7 +458,7 @@ RestoreArchive(Archive *AHX, bool append_data)
 	 */
 	sav = SaveOutput(AH);
 	if (ropt->filename || ropt->compression_spec.algorithm != PG_COMPRESSION_NONE)
-		SetOutput(AH, ropt->filename, ropt->compression_spec, append_data);
+		SetOutput(AH, ropt->filename, ropt->compression_spec);
 
 	ahprintf(AH, "--\n-- PostgreSQL database dump\n--\n\n");
 
@@ -1300,7 +1297,7 @@ PrintTOCSummary(Archive *AHX)
 
 	sav = SaveOutput(AH);
 	if (ropt->filename)
-		SetOutput(AH, ropt->filename, out_compression_spec, false);
+		SetOutput(AH, ropt->filename, out_compression_spec);
 
 	if (strftime(stamp_str, sizeof(stamp_str), PGDUMP_STRFTIME_FMT,
 				 localtime(&AH->createDate)) == 0)
@@ -1679,8 +1676,7 @@ archprintf(Archive *AH, const char *fmt,...)
 
 static void
 SetOutput(ArchiveHandle *AH, const char *filename,
-		  const pg_compress_specification compression_spec,
-		  bool append_data)
+		  const pg_compress_specification compression_spec)
 {
 	CompressFileHandle *CFH;
 	const char *mode;
@@ -1700,7 +1696,7 @@ SetOutput(ArchiveHandle *AH, const char *filename,
 	else
 		fn = fileno(stdout);
 
-	if (append_data || AH->mode == archModeAppend)
+	if (AH->mode == archModeAppend)
 		mode = PG_BINARY_A;
 	else
 		mode = PG_BINARY_W;
@@ -2974,6 +2970,19 @@ _tocEntryRequired(TocEntry *te, teSection curSection, ArchiveHandle *AH)
 	int			res = REQ_SCHEMA | REQ_DATA;
 	RestoreOptions *ropt = AH->public.ropt;
 
+	/*
+	 * For binary upgrade mode, dump pg_largeobject_metadata and the
+	 * associated pg_shdepend rows. This is faster to restore than the
+	 * equivalent set of large object commands.  We can only do this for
+	 * upgrades from v12 and newer; in older versions, pg_largeobject_metadata
+	 * was created WITH OIDS, so the OID column is hidden and won't be dumped.
+	 */
+	if (ropt->binary_upgrade && AH->public.remoteVersion >= 120000 &&
+		strcmp(te->desc, "TABLE DATA") == 0 &&
+		(te->catalogId.oid == LargeObjectMetadataRelationId ||
+		 te->catalogId.oid == SharedDependRelationId))
+		return REQ_DATA;
+
 	/* These items are treated specially */
 	if (strcmp(te->desc, "ENCODING") == 0 ||
 		strcmp(te->desc, "STDSTRINGS") == 0 ||
diff --git a/src/bin/pg_dump/pg_backup_archiver.h b/src/bin/pg_dump/pg_backup_archiver.h
index 365073b3eae45..325b53fc9bd4b 100644
--- a/src/bin/pg_dump/pg_backup_archiver.h
+++ b/src/bin/pg_dump/pg_backup_archiver.h
@@ -394,7 +394,6 @@ struct _tocEntry
 
 extern int	parallel_restore(ArchiveHandle *AH, TocEntry *te);
 extern void on_exit_close_archive(Archive *AHX);
-extern void replace_on_exit_close_archive(Archive *AHX);
 
 extern void warn_or_exit_horribly(ArchiveHandle *AH, const char *fmt,...) pg_attribute_printf(2, 3);
 
diff --git a/src/bin/pg_dump/pg_backup_tar.c b/src/bin/pg_dump/pg_backup_tar.c
index d94d0de2a5d17..b5ba3b46dd999 100644
--- a/src/bin/pg_dump/pg_backup_tar.c
+++ b/src/bin/pg_dump/pg_backup_tar.c
@@ -826,7 +826,7 @@ _CloseArchive(ArchiveHandle *AH)
 		savVerbose = AH->public.verbose;
 		AH->public.verbose = 0;
 
-		RestoreArchive((Archive *) AH, false);
+		RestoreArchive((Archive *) AH);
 
 		SetArchiveOptions((Archive *) AH, savDopt, savRopt);
 
diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c
index 1937997ea674d..f3a353a61a58e 100644
--- a/src/bin/pg_dump/pg_dump.c
+++ b/src/bin/pg_dump/pg_dump.c
@@ -47,10 +47,13 @@
 #include "catalog/pg_authid_d.h"
 #include "catalog/pg_cast_d.h"
 #include "catalog/pg_class_d.h"
+#include "catalog/pg_constraint_d.h"
 #include "catalog/pg_default_acl_d.h"
 #include "catalog/pg_largeobject_d.h"
+#include "catalog/pg_largeobject_metadata_d.h"
 #include "catalog/pg_proc_d.h"
 #include "catalog/pg_publication_d.h"
+#include "catalog/pg_shdepend_d.h"
 #include "catalog/pg_subscription_d.h"
 #include "catalog/pg_type_d.h"
 #include "common/connect.h"
@@ -209,6 +212,12 @@ static int	nbinaryUpgradeClassOids = 0;
 static SequenceItem *sequences = NULL;
 static int	nsequences = 0;
 
+/*
+ * For binary upgrade, the dump ID of pg_largeobject_metadata is saved for use
+ * as a dependency for pg_shdepend and any large object comments/seclabels.
+ */
+static DumpId lo_metadata_dumpId;
+
 /* Maximum number of relations to fetch in a fetchAttributeStats() call. */
 #define MAX_ATTR_STATS_RELS 64
 
@@ -440,8 +449,6 @@ main(int argc, char **argv)
 	bool		data_only = false;
 	bool		schema_only = false;
 	bool		statistics_only = false;
-	bool		with_data = false;
-	bool		with_schema = false;
 	bool		with_statistics = false;
 	bool		no_data = false;
 	bool		no_schema = false;
@@ -505,6 +512,7 @@ main(int argc, char **argv)
 		{"section", required_argument, NULL, 5},
 		{"serializable-deferrable", no_argument, &dopt.serializable_deferrable, 1},
 		{"snapshot", required_argument, NULL, 6},
+		{"statistics", no_argument, NULL, 22},
 		{"statistics-only", no_argument, NULL, 18},
 		{"strict-names", no_argument, &strict_names, 1},
 		{"use-set-session-authorization", no_argument, &dopt.use_setsessauth, 1},
@@ -519,9 +527,6 @@ main(int argc, char **argv)
 		{"no-toast-compression", no_argument, &dopt.no_toast_compression, 1},
 		{"no-unlogged-table-data", no_argument, &dopt.no_unlogged_table_data, 1},
 		{"no-sync", no_argument, NULL, 7},
-		{"with-data", no_argument, NULL, 22},
-		{"with-schema", no_argument, NULL, 23},
-		{"with-statistics", no_argument, NULL, 24},
 		{"on-conflict-do-nothing", no_argument, &dopt.do_nothing, 1},
 		{"rows-per-insert", required_argument, NULL, 10},
 		{"include-foreign-data", required_argument, NULL, 11},
@@ -789,14 +794,6 @@ main(int argc, char **argv)
 				break;
 
 			case 22:
-				with_data = true;
-				break;
-
-			case 23:
-				with_schema = true;
-				break;
-
-			case 24:
 				with_statistics = true;
 				break;
 
@@ -843,13 +840,17 @@ main(int argc, char **argv)
 	if (statistics_only && no_statistics)
 		pg_fatal("options --statistics-only and --no-statistics cannot be used together");
 
-	/* reject conflicting "with-" and "no-" options */
-	if (with_data && no_data)
-		pg_fatal("options --with-data and --no-data cannot be used together");
-	if (with_schema && no_schema)
-		pg_fatal("options --with-schema and --no-schema cannot be used together");
+	/* reject conflicting "no-" options */
 	if (with_statistics && no_statistics)
-		pg_fatal("options --with-statistics and --no-statistics cannot be used together");
+		pg_fatal("options --statistics and --no-statistics cannot be used together");
+
+	/* reject conflicting "-only" options */
+	if (data_only && with_statistics)
+		pg_fatal("options %s and %s cannot be used together",
+				 "-a/--data-only", "--statistics");
+	if (schema_only && with_statistics)
+		pg_fatal("options %s and %s cannot be used together",
+				 "-s/--schema-only", "--statistics");
 
 	if (schema_only && foreign_servers_include_patterns.head != NULL)
 		pg_fatal("options -s/--schema-only and --include-foreign-data cannot be used together");
@@ -864,16 +865,14 @@ main(int argc, char **argv)
 		pg_fatal("option --if-exists requires option -c/--clean");
 
 	/*
-	 * Set derivative flags. An "-only" option may be overridden by an
-	 * explicit "with-" option; e.g. "--schema-only --with-statistics" will
-	 * include schema and statistics. Other ambiguous or nonsensical
-	 * combinations, e.g. "--schema-only --no-schema", will have already
-	 * caused an error in one of the checks above.
+	 * Set derivative flags. Ambiguous or nonsensical combinations, e.g.
+	 * "--schema-only --no-schema", will have already caused an error in one
+	 * of the checks above.
 	 */
 	dopt.dumpData = ((dopt.dumpData && !schema_only && !statistics_only) ||
-					 (data_only || with_data)) && !no_data;
+					 data_only) && !no_data;
 	dopt.dumpSchema = ((dopt.dumpSchema && !data_only && !statistics_only) ||
-					   (schema_only || with_schema)) && !no_schema;
+					   schema_only) && !no_schema;
 	dopt.dumpStatistics = ((dopt.dumpStatistics && !schema_only && !data_only) ||
 						   (statistics_only || with_statistics)) && !no_statistics;
 
@@ -1085,6 +1084,36 @@ main(int argc, char **argv)
 	if (!dopt.dumpData && dopt.sequence_data)
 		getTableData(&dopt, tblinfo, numTables, RELKIND_SEQUENCE);
 
+	/*
+	 * For binary upgrade mode, dump pg_largeobject_metadata and the
+	 * associated pg_shdepend rows. This is faster to restore than the
+	 * equivalent set of large object commands.  We can only do this for
+	 * upgrades from v12 and newer; in older versions, pg_largeobject_metadata
+	 * was created WITH OIDS, so the OID column is hidden and won't be dumped.
+	 */
+	if (dopt.binary_upgrade && fout->remoteVersion >= 120000)
+	{
+		TableInfo  *lo_metadata = findTableByOid(LargeObjectMetadataRelationId);
+		TableInfo  *shdepend = findTableByOid(SharedDependRelationId);
+
+		makeTableDataInfo(&dopt, lo_metadata);
+		makeTableDataInfo(&dopt, shdepend);
+
+		/*
+		 * Save pg_largeobject_metadata's dump ID for use as a dependency for
+		 * pg_shdepend and any large object comments/seclabels.
+		 */
+		lo_metadata_dumpId = lo_metadata->dataObj->dobj.dumpId;
+		addObjectDependency(&shdepend->dataObj->dobj, lo_metadata_dumpId);
+
+		/*
+		 * Only dump large object shdepend rows for this database.
+		 */
+		shdepend->dataObj->filtercond = "WHERE classid = 'pg_largeobject'::regclass "
+			"AND dbid = (SELECT oid FROM pg_database "
+			"            WHERE datname = current_database())";
+	}
+
 	/*
 	 * In binary-upgrade mode, we do not have to worry about the actual LO
 	 * data or the associated metadata that resides in the pg_largeobject and
@@ -1226,7 +1255,7 @@ main(int argc, char **argv)
 	 * right now.
 	 */
 	if (plainText)
-		RestoreArchive(fout, false);
+		RestoreArchive(fout);
 
 	CloseArchive(fout);
 
@@ -1316,6 +1345,7 @@ help(const char *progname)
 	printf(_("  --sequence-data              include sequence data in dump\n"));
 	printf(_("  --serializable-deferrable    wait until the dump can run without anomalies\n"));
 	printf(_("  --snapshot=SNAPSHOT          use given snapshot for the dump\n"));
+	printf(_("  --statistics                 dump the statistics\n"));
 	printf(_("  --statistics-only            dump only the statistics, not schema or data\n"));
 	printf(_("  --strict-names               require table and/or schema include patterns to\n"
 			 "                               match at least one entity each\n"));
@@ -1324,9 +1354,6 @@ help(const char *progname)
 	printf(_("  --use-set-session-authorization\n"
 			 "                               use SET SESSION AUTHORIZATION commands instead of\n"
 			 "                               ALTER OWNER commands to set ownership\n"));
-	printf(_("  --with-data                  dump the data\n"));
-	printf(_("  --with-schema                dump the schema\n"));
-	printf(_("  --with-statistics            dump the statistics\n"));
 
 	printf(_("\nConnection options:\n"));
 	printf(_("  -d, --dbname=DBNAME      database to dump\n"));
@@ -2168,6 +2195,13 @@ selectDumpableProcLang(ProcLangInfo *plang, Archive *fout)
 static void
 selectDumpableAccessMethod(AccessMethodInfo *method, Archive *fout)
 {
+	/* see getAccessMethods() comment about v9.6. */
+	if (fout->remoteVersion < 90600)
+	{
+		method->dobj.dump = DUMP_COMPONENT_NONE;
+		return;
+	}
+
 	if (checkExtensionMembership(&method->dobj, fout))
 		return;					/* extension membership overrides all else */
 
@@ -3924,10 +3958,37 @@ getLOs(Archive *fout)
 		 * as it will be copied by pg_upgrade, which simply copies the
 		 * pg_largeobject table. We *do* however dump out anything but the
 		 * data, as pg_upgrade copies just pg_largeobject, but not
-		 * pg_largeobject_metadata, after the dump is restored.
+		 * pg_largeobject_metadata, after the dump is restored.  In versions
+		 * before v12, this is done via proper large object commands.  In
+		 * newer versions, we dump the content of pg_largeobject_metadata and
+		 * any associated pg_shdepend rows, which is faster to restore.  (On
+		 * <v12, pg_largeobject_metadata was created WITH OIDS, so the OID
+		 * column is hidden and won't be dumped.)
 		 */
 		if (dopt->binary_upgrade)
-			loinfo->dobj.dump &= ~DUMP_COMPONENT_DATA;
+		{
+			if (fout->remoteVersion >= 120000)
+			{
+				/*
+				 * We should've saved pg_largeobject_metadata's dump ID before
+				 * this point.
+				 */
+				Assert(lo_metadata_dumpId);
+
+				loinfo->dobj.dump &= ~(DUMP_COMPONENT_DATA | DUMP_COMPONENT_ACL | DUMP_COMPONENT_DEFINITION);
+
+				/*
+				 * Mark the large object as dependent on
+				 * pg_largeobject_metadata so that any large object
+				 * comments/seclables are dumped after it.
+				 */
+				loinfo->dobj.dependencies = (DumpId *) pg_malloc(sizeof(DumpId));
+				loinfo->dobj.dependencies[0] = lo_metadata_dumpId;
+				loinfo->dobj.nDeps = loinfo->dobj.allocDeps = 1;
+			}
+			else
+				loinfo->dobj.dump &= ~DUMP_COMPONENT_DATA;
+		}
 
 		/*
 		 * Create a "BLOBS" data item for the group, too. This is just a
@@ -4962,6 +5023,7 @@ getSubscriptions(Archive *fout)
 	int			i_suboriginremotelsn;
 	int			i_subenabled;
 	int			i_subfailover;
+	int			i_subretaindeadtuples;
 	int			i,
 				ntups;
 
@@ -5034,10 +5096,17 @@ getSubscriptions(Archive *fout)
 
 	if (fout->remoteVersion >= 170000)
 		appendPQExpBufferStr(query,
-							 " s.subfailover\n");
+							 " s.subfailover,\n");
 	else
 		appendPQExpBufferStr(query,
-							 " false AS subfailover\n");
+							 " false AS subfailover,\n");
+
+	if (fout->remoteVersion >= 190000)
+		appendPQExpBufferStr(query,
+							 " s.subretaindeadtuples\n");
+	else
+		appendPQExpBufferStr(query,
+							 " false AS subretaindeadtuples\n");
 
 	appendPQExpBufferStr(query,
 						 "FROM pg_subscription s\n");
@@ -5071,6 +5140,7 @@ getSubscriptions(Archive *fout)
 	i_subpasswordrequired = PQfnumber(res, "subpasswordrequired");
 	i_subrunasowner = PQfnumber(res, "subrunasowner");
 	i_subfailover = PQfnumber(res, "subfailover");
+	i_subretaindeadtuples = PQfnumber(res, "subretaindeadtuples");
 	i_subconninfo = PQfnumber(res, "subconninfo");
 	i_subslotname = PQfnumber(res, "subslotname");
 	i_subsynccommit = PQfnumber(res, "subsynccommit");
@@ -5104,6 +5174,8 @@ getSubscriptions(Archive *fout)
 			(strcmp(PQgetvalue(res, i, i_subrunasowner), "t") == 0);
 		subinfo[i].subfailover =
 			(strcmp(PQgetvalue(res, i, i_subfailover), "t") == 0);
+		subinfo[i].subretaindeadtuples =
+			(strcmp(PQgetvalue(res, i, i_subretaindeadtuples), "t") == 0);
 		subinfo[i].subconninfo =
 			pg_strdup(PQgetvalue(res, i, i_subconninfo));
 		if (PQgetisnull(res, i, i_subslotname))
@@ -5362,6 +5434,9 @@ dumpSubscription(Archive *fout, const SubscriptionInfo *subinfo)
 	if (subinfo->subfailover)
 		appendPQExpBufferStr(query, ", failover = true");
 
+	if (subinfo->subretaindeadtuples)
+		appendPQExpBufferStr(query, ", retain_dead_tuples = true");
+
 	if (strcmp(subinfo->subsynccommit, "off") != 0)
 		appendPQExpBuffer(query, ", synchronous_commit = %s", fmtId(subinfo->subsynccommit));
 
@@ -6122,6 +6197,7 @@ getTypes(Archive *fout)
 		 */
 		tyinfo[i].nDomChecks = 0;
 		tyinfo[i].domChecks = NULL;
+		tyinfo[i].notnull = NULL;
 		if ((tyinfo[i].dobj.dump & DUMP_COMPONENT_DEFINITION) &&
 			tyinfo[i].typtype == TYPTYPE_DOMAIN)
 			getDomainConstraints(fout, &(tyinfo[i]));
@@ -6181,6 +6257,8 @@ getOperators(Archive *fout)
 	int			i_oprnamespace;
 	int			i_oprowner;
 	int			i_oprkind;
+	int			i_oprleft;
+	int			i_oprright;
 	int			i_oprcode;
 
 	/*
@@ -6192,6 +6270,8 @@ getOperators(Archive *fout)
 						 "oprnamespace, "
 						 "oprowner, "
 						 "oprkind, "
+						 "oprleft, "
+						 "oprright, "
 						 "oprcode::oid AS oprcode "
 						 "FROM pg_operator");
 
@@ -6207,6 +6287,8 @@ getOperators(Archive *fout)
 	i_oprnamespace = PQfnumber(res, "oprnamespace");
 	i_oprowner = PQfnumber(res, "oprowner");
 	i_oprkind = PQfnumber(res, "oprkind");
+	i_oprleft = PQfnumber(res, "oprleft");
+	i_oprright = PQfnumber(res, "oprright");
 	i_oprcode = PQfnumber(res, "oprcode");
 
 	for (i = 0; i < ntups; i++)
@@ -6220,6 +6302,8 @@ getOperators(Archive *fout)
 			findNamespace(atooid(PQgetvalue(res, i, i_oprnamespace)));
 		oprinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_oprowner));
 		oprinfo[i].oprkind = (PQgetvalue(res, i, i_oprkind))[0];
+		oprinfo[i].oprleft = atooid(PQgetvalue(res, i, i_oprleft));
+		oprinfo[i].oprright = atooid(PQgetvalue(res, i, i_oprright));
 		oprinfo[i].oprcode = atooid(PQgetvalue(res, i, i_oprcode));
 
 		/* Decide whether we want to dump it */
@@ -6248,6 +6332,7 @@ getCollations(Archive *fout)
 	int			i_collname;
 	int			i_collnamespace;
 	int			i_collowner;
+	int			i_collencoding;
 
 	query = createPQExpBuffer();
 
@@ -6258,7 +6343,8 @@ getCollations(Archive *fout)
 
 	appendPQExpBufferStr(query, "SELECT tableoid, oid, collname, "
 						 "collnamespace, "
-						 "collowner "
+						 "collowner, "
+						 "collencoding "
 						 "FROM pg_collation");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
@@ -6272,6 +6358,7 @@ getCollations(Archive *fout)
 	i_collname = PQfnumber(res, "collname");
 	i_collnamespace = PQfnumber(res, "collnamespace");
 	i_collowner = PQfnumber(res, "collowner");
+	i_collencoding = PQfnumber(res, "collencoding");
 
 	for (i = 0; i < ntups; i++)
 	{
@@ -6283,6 +6370,7 @@ getCollations(Archive *fout)
 		collinfo[i].dobj.namespace =
 			findNamespace(atooid(PQgetvalue(res, i, i_collnamespace)));
 		collinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_collowner));
+		collinfo[i].collencoding = atoi(PQgetvalue(res, i, i_collencoding));
 
 		/* Decide whether we want to dump it */
 		selectDumpableObject(&(collinfo[i].dobj), fout);
@@ -6373,16 +6461,28 @@ getAccessMethods(Archive *fout)
 	int			i_amhandler;
 	int			i_amtype;
 
-	/* Before 9.6, there are no user-defined access methods */
-	if (fout->remoteVersion < 90600)
-		return;
-
 	query = createPQExpBuffer();
 
-	/* Select all access methods from pg_am table */
-	appendPQExpBufferStr(query, "SELECT tableoid, oid, amname, amtype, "
-						 "amhandler::pg_catalog.regproc AS amhandler "
-						 "FROM pg_am");
+	/*
+	 * Select all access methods from pg_am table.  v9.6 introduced CREATE
+	 * ACCESS METHOD, so earlier versions usually have only built-in access
+	 * methods.  v9.6 also changed the access method API, replacing dozens of
+	 * pg_am columns with amhandler.  Even if a user created an access method
+	 * by "INSERT INTO pg_am", we have no way to translate pre-v9.6 pg_am
+	 * columns to a v9.6+ CREATE ACCESS METHOD.  Hence, before v9.6, read
+	 * pg_am just to facilitate findAccessMethodByOid() providing the
+	 * OID-to-name mapping.
+	 */
+	appendPQExpBufferStr(query, "SELECT tableoid, oid, amname, ");
+	if (fout->remoteVersion >= 90600)
+		appendPQExpBufferStr(query,
+							 "amtype, "
+							 "amhandler::pg_catalog.regproc AS amhandler ");
+	else
+		appendPQExpBufferStr(query,
+							 "'i'::pg_catalog.\"char\" AS amtype, "
+							 "'-'::pg_catalog.regproc AS amhandler ");
+	appendPQExpBufferStr(query, "FROM pg_am");
 
 	res = ExecuteSqlQuery(fout, query->data, PGRES_TUPLES_OK);
 
@@ -6431,6 +6531,7 @@ getOpclasses(Archive *fout)
 	OpclassInfo *opcinfo;
 	int			i_tableoid;
 	int			i_oid;
+	int			i_opcmethod;
 	int			i_opcname;
 	int			i_opcnamespace;
 	int			i_opcowner;
@@ -6440,7 +6541,7 @@ getOpclasses(Archive *fout)
 	 * system-defined opclasses at dump-out time.
 	 */
 
-	appendPQExpBufferStr(query, "SELECT tableoid, oid, opcname, "
+	appendPQExpBufferStr(query, "SELECT tableoid, oid, opcmethod, opcname, "
 						 "opcnamespace, "
 						 "opcowner "
 						 "FROM pg_opclass");
@@ -6453,6 +6554,7 @@ getOpclasses(Archive *fout)
 
 	i_tableoid = PQfnumber(res, "tableoid");
 	i_oid = PQfnumber(res, "oid");
+	i_opcmethod = PQfnumber(res, "opcmethod");
 	i_opcname = PQfnumber(res, "opcname");
 	i_opcnamespace = PQfnumber(res, "opcnamespace");
 	i_opcowner = PQfnumber(res, "opcowner");
@@ -6466,6 +6568,7 @@ getOpclasses(Archive *fout)
 		opcinfo[i].dobj.name = pg_strdup(PQgetvalue(res, i, i_opcname));
 		opcinfo[i].dobj.namespace =
 			findNamespace(atooid(PQgetvalue(res, i, i_opcnamespace)));
+		opcinfo[i].opcmethod = atooid(PQgetvalue(res, i, i_opcmethod));
 		opcinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_opcowner));
 
 		/* Decide whether we want to dump it */
@@ -6491,6 +6594,7 @@ getOpfamilies(Archive *fout)
 	OpfamilyInfo *opfinfo;
 	int			i_tableoid;
 	int			i_oid;
+	int			i_opfmethod;
 	int			i_opfname;
 	int			i_opfnamespace;
 	int			i_opfowner;
@@ -6502,7 +6606,7 @@ getOpfamilies(Archive *fout)
 	 * system-defined opfamilies at dump-out time.
 	 */
 
-	appendPQExpBufferStr(query, "SELECT tableoid, oid, opfname, "
+	appendPQExpBufferStr(query, "SELECT tableoid, oid, opfmethod, opfname, "
 						 "opfnamespace, "
 						 "opfowner "
 						 "FROM pg_opfamily");
@@ -6516,6 +6620,7 @@ getOpfamilies(Archive *fout)
 	i_tableoid = PQfnumber(res, "tableoid");
 	i_oid = PQfnumber(res, "oid");
 	i_opfname = PQfnumber(res, "opfname");
+	i_opfmethod = PQfnumber(res, "opfmethod");
 	i_opfnamespace = PQfnumber(res, "opfnamespace");
 	i_opfowner = PQfnumber(res, "opfowner");
 
@@ -6528,6 +6633,7 @@ getOpfamilies(Archive *fout)
 		opfinfo[i].dobj.name = pg_strdup(PQgetvalue(res, i, i_opfname));
 		opfinfo[i].dobj.namespace =
 			findNamespace(atooid(PQgetvalue(res, i, i_opfnamespace)));
+		opfinfo[i].opfmethod = atooid(PQgetvalue(res, i, i_opfmethod));
 		opfinfo[i].rolname = getRoleName(PQgetvalue(res, i, i_opfowner));
 
 		/* Decide whether we want to dump it */
@@ -8247,27 +8353,33 @@ addConstrChildIdxDeps(DumpableObject *dobj, const IndxInfo *refidx)
 static void
 getDomainConstraints(Archive *fout, TypeInfo *tyinfo)
 {
-	int			i;
 	ConstraintInfo *constrinfo;
 	PQExpBuffer query = createPQExpBuffer();
 	PGresult   *res;
 	int			i_tableoid,
 				i_oid,
 				i_conname,
-				i_consrc;
+				i_consrc,
+				i_convalidated,
+				i_contype;
 	int			ntups;
 
 	if (!fout->is_prepared[PREPQUERY_GETDOMAINCONSTRAINTS])
 	{
-		/* Set up query for constraint-specific details */
-		appendPQExpBufferStr(query,
-							 "PREPARE getDomainConstraints(pg_catalog.oid) AS\n"
-							 "SELECT tableoid, oid, conname, "
-							 "pg_catalog.pg_get_constraintdef(oid) AS consrc, "
-							 "convalidated "
-							 "FROM pg_catalog.pg_constraint "
-							 "WHERE contypid = $1 AND contype = 'c' "
-							 "ORDER BY conname");
+		/*
+		 * Set up query for constraint-specific details.  For servers 17 and
+		 * up, domains have constraints of type 'n' as well as 'c', otherwise
+		 * just the latter.
+		 */
+		appendPQExpBuffer(query,
+						  "PREPARE getDomainConstraints(pg_catalog.oid) AS\n"
+						  "SELECT tableoid, oid, conname, "
+						  "pg_catalog.pg_get_constraintdef(oid) AS consrc, "
+						  "convalidated, contype "
+						  "FROM pg_catalog.pg_constraint "
+						  "WHERE contypid = $1 AND contype IN (%s) "
+						  "ORDER BY conname",
+						  fout->remoteVersion < 170000 ? "'c'" : "'c', 'n'");
 
 		ExecuteSqlStatement(fout, query->data);
 
@@ -8286,33 +8398,50 @@ getDomainConstraints(Archive *fout, TypeInfo *tyinfo)
 	i_oid = PQfnumber(res, "oid");
 	i_conname = PQfnumber(res, "conname");
 	i_consrc = PQfnumber(res, "consrc");
+	i_convalidated = PQfnumber(res, "convalidated");
+	i_contype = PQfnumber(res, "contype");
 
 	constrinfo = (ConstraintInfo *) pg_malloc(ntups * sizeof(ConstraintInfo));
-
-	tyinfo->nDomChecks = ntups;
 	tyinfo->domChecks = constrinfo;
 
-	for (i = 0; i < ntups; i++)
+	/* 'i' tracks result rows; 'j' counts CHECK constraints */
+	for (int i = 0, j = 0; i < ntups; i++)
 	{
-		bool		validated = PQgetvalue(res, i, 4)[0] == 't';
-
-		constrinfo[i].dobj.objType = DO_CONSTRAINT;
-		constrinfo[i].dobj.catId.tableoid = atooid(PQgetvalue(res, i, i_tableoid));
-		constrinfo[i].dobj.catId.oid = atooid(PQgetvalue(res, i, i_oid));
-		AssignDumpId(&constrinfo[i].dobj);
-		constrinfo[i].dobj.name = pg_strdup(PQgetvalue(res, i, i_conname));
-		constrinfo[i].dobj.namespace = tyinfo->dobj.namespace;
-		constrinfo[i].contable = NULL;
-		constrinfo[i].condomain = tyinfo;
-		constrinfo[i].contype = 'c';
-		constrinfo[i].condef = pg_strdup(PQgetvalue(res, i, i_consrc));
-		constrinfo[i].confrelid = InvalidOid;
-		constrinfo[i].conindex = 0;
-		constrinfo[i].condeferrable = false;
-		constrinfo[i].condeferred = false;
-		constrinfo[i].conislocal = true;
-
-		constrinfo[i].separate = !validated;
+		bool		validated = PQgetvalue(res, i, i_convalidated)[0] == 't';
+		char		contype = (PQgetvalue(res, i, i_contype))[0];
+		ConstraintInfo *constraint;
+
+		if (contype == CONSTRAINT_CHECK)
+		{
+			constraint = &constrinfo[j++];
+			tyinfo->nDomChecks++;
+		}
+		else
+		{
+			Assert(contype == CONSTRAINT_NOTNULL);
+			Assert(tyinfo->notnull == NULL);
+			/* use last item in array for the not-null constraint */
+			tyinfo->notnull = &(constrinfo[ntups - 1]);
+			constraint = tyinfo->notnull;
+		}
+
+		constraint->dobj.objType = DO_CONSTRAINT;
+		constraint->dobj.catId.tableoid = atooid(PQgetvalue(res, i, i_tableoid));
+		constraint->dobj.catId.oid = atooid(PQgetvalue(res, i, i_oid));
+		AssignDumpId(&(constraint->dobj));
+		constraint->dobj.name = pg_strdup(PQgetvalue(res, i, i_conname));
+		constraint->dobj.namespace = tyinfo->dobj.namespace;
+		constraint->contable = NULL;
+		constraint->condomain = tyinfo;
+		constraint->contype = contype;
+		constraint->condef = pg_strdup(PQgetvalue(res, i, i_consrc));
+		constraint->confrelid = InvalidOid;
+		constraint->conindex = 0;
+		constraint->condeferrable = false;
+		constraint->condeferred = false;
+		constraint->conislocal = true;
+
+		constraint->separate = !validated;
 
 		/*
 		 * Make the domain depend on the constraint, ensuring it won't be
@@ -8321,8 +8450,7 @@ getDomainConstraints(Archive *fout, TypeInfo *tyinfo)
 		 * anyway, so this doesn't matter.
 		 */
 		if (validated)
-			addObjectDependency(&tyinfo->dobj,
-								constrinfo[i].dobj.dumpId);
+			addObjectDependency(&tyinfo->dobj, constraint->dobj.dumpId);
 	}
 
 	PQclear(res);
@@ -9039,8 +9167,20 @@ getTableAttrs(Archive *fout, TableInfo *tblinfo, int numTables)
 		if (tbinfo->relkind == RELKIND_SEQUENCE)
 			continue;
 
-		/* Don't bother with uninteresting tables, either */
-		if (!tbinfo->interesting)
+		/*
+		 * Don't bother with uninteresting tables, either.  For binary
+		 * upgrades, this is bypassed for pg_largeobject_metadata and
+		 * pg_shdepend so that the columns names are collected for the
+		 * corresponding COPY commands.  Restoring the data for those catalogs
+		 * is faster than restoring the equivalent set of large object
+		 * commands.  We can only do this for upgrades from v12 and newer; in
+		 * older versions, pg_largeobject_metadata was created WITH OIDS, so
+		 * the OID column is hidden and won't be dumped.
+		 */
+		if (!tbinfo->interesting &&
+			!(fout->dopt->binary_upgrade && fout->remoteVersion >= 120000 &&
+			  (tbinfo->dobj.catId.oid == LargeObjectMetadataRelationId ||
+			   tbinfo->dobj.catId.oid == SharedDependRelationId)))
 			continue;
 
 		/* OK, we need info for this table */
@@ -9244,7 +9384,10 @@ getTableAttrs(Archive *fout, TableInfo *tblinfo, int numTables)
 			pg_fatal("unrecognized table OID %u", attrelid);
 		/* cross-check that we only got requested tables */
 		if (tbinfo->relkind == RELKIND_SEQUENCE ||
-			!tbinfo->interesting)
+			(!tbinfo->interesting &&
+			 !(fout->dopt->binary_upgrade && fout->remoteVersion >= 120000 &&
+			   (tbinfo->dobj.catId.oid == LargeObjectMetadataRelationId ||
+				tbinfo->dobj.catId.oid == SharedDependRelationId))))
 			pg_fatal("unexpected column data for table \"%s\"",
 					 tbinfo->dobj.name);
 
@@ -12517,8 +12660,36 @@ dumpDomain(Archive *fout, const TypeInfo *tyinfo)
 			appendPQExpBuffer(q, " COLLATE %s", fmtQualifiedDumpable(coll));
 	}
 
+	/*
+	 * Print a not-null constraint if there's one.  In servers older than 17
+	 * these don't have names, so just print it unadorned; in newer ones they
+	 * do, but most of the time it's going to be the standard generated one,
+	 * so omit the name in that case also.
+	 */
 	if (typnotnull[0] == 't')
-		appendPQExpBufferStr(q, " NOT NULL");
+	{
+		if (fout->remoteVersion < 170000 || tyinfo->notnull == NULL)
+			appendPQExpBufferStr(q, " NOT NULL");
+		else
+		{
+			ConstraintInfo *notnull = tyinfo->notnull;
+
+			if (!notnull->separate)
+			{
+				char	   *default_name;
+
+				/* XXX should match ChooseConstraintName better */
+				default_name = psprintf("%s_not_null", tyinfo->dobj.name);
+
+				if (strcmp(default_name, notnull->dobj.name) == 0)
+					appendPQExpBufferStr(q, " NOT NULL");
+				else
+					appendPQExpBuffer(q, " CONSTRAINT %s %s",
+									  fmtId(notnull->dobj.name), notnull->condef);
+				free(default_name);
+			}
+		}
+	}
 
 	if (typdefault != NULL)
 	{
@@ -12538,7 +12709,7 @@ dumpDomain(Archive *fout, const TypeInfo *tyinfo)
 	{
 		ConstraintInfo *domcheck = &(tyinfo->domChecks[i]);
 
-		if (!domcheck->separate)
+		if (!domcheck->separate && domcheck->contype == 'c')
 			appendPQExpBuffer(q, "\n\tCONSTRAINT %s %s",
 							  fmtId(domcheck->dobj.name), domcheck->condef);
 	}
@@ -12583,8 +12754,13 @@ dumpDomain(Archive *fout, const TypeInfo *tyinfo)
 	for (i = 0; i < tyinfo->nDomChecks; i++)
 	{
 		ConstraintInfo *domcheck = &(tyinfo->domChecks[i]);
-		PQExpBuffer conprefix = createPQExpBuffer();
+		PQExpBuffer conprefix;
+
+		/* but only if the constraint itself was dumped here */
+		if (domcheck->separate)
+			continue;
 
+		conprefix = createPQExpBuffer();
 		appendPQExpBuffer(conprefix, "CONSTRAINT %s ON DOMAIN",
 						  fmtId(domcheck->dobj.name));
 
@@ -12597,6 +12773,25 @@ dumpDomain(Archive *fout, const TypeInfo *tyinfo)
 		destroyPQExpBuffer(conprefix);
 	}
 
+	/*
+	 * And a comment on the not-null constraint, if there's one -- but only if
+	 * the constraint itself was dumped here
+	 */
+	if (tyinfo->notnull != NULL && !tyinfo->notnull->separate)
+	{
+		PQExpBuffer conprefix = createPQExpBuffer();
+
+		appendPQExpBuffer(conprefix, "CONSTRAINT %s ON DOMAIN",
+						  fmtId(tyinfo->notnull->dobj.name));
+
+		if (tyinfo->notnull->dobj.dump & DUMP_COMPONENT_COMMENT)
+			dumpComment(fout, conprefix->data, qtypname,
+						tyinfo->dobj.namespace->dobj.name,
+						tyinfo->rolname,
+						tyinfo->notnull->dobj.catId, 0, tyinfo->dobj.dumpId);
+		destroyPQExpBuffer(conprefix);
+	}
+
 	destroyPQExpBuffer(q);
 	destroyPQExpBuffer(delq);
 	destroyPQExpBuffer(query);
@@ -18458,14 +18653,23 @@ dumpConstraint(Archive *fout, const ConstraintInfo *coninfo)
 										  .dropStmt = delq->data));
 		}
 	}
-	else if (coninfo->contype == 'c' && tbinfo == NULL)
+	else if (tbinfo == NULL)
 	{
-		/* CHECK constraint on a domain */
+		/* CHECK, NOT NULL constraint on a domain */
 		TypeInfo   *tyinfo = coninfo->condomain;
 
+		Assert(coninfo->contype == 'c' || coninfo->contype == 'n');
+
 		/* Ignore if not to be dumped separately */
 		if (coninfo->separate)
 		{
+			const char *keyword;
+
+			if (coninfo->contype == 'c')
+				keyword = "CHECK CONSTRAINT";
+			else
+				keyword = "CONSTRAINT";
+
 			appendPQExpBuffer(q, "ALTER DOMAIN %s\n",
 							  fmtQualifiedDumpable(tyinfo));
 			appendPQExpBuffer(q, "    ADD CONSTRAINT %s %s;\n",
@@ -18484,10 +18688,26 @@ dumpConstraint(Archive *fout, const ConstraintInfo *coninfo)
 							 ARCHIVE_OPTS(.tag = tag,
 										  .namespace = tyinfo->dobj.namespace->dobj.name,
 										  .owner = tyinfo->rolname,
-										  .description = "CHECK CONSTRAINT",
+										  .description = keyword,
 										  .section = SECTION_POST_DATA,
 										  .createStmt = q->data,
 										  .dropStmt = delq->data));
+
+			if (coninfo->dobj.dump & DUMP_COMPONENT_COMMENT)
+			{
+				PQExpBuffer conprefix = createPQExpBuffer();
+				char	   *qtypname = pg_strdup(fmtId(tyinfo->dobj.name));
+
+				appendPQExpBuffer(conprefix, "CONSTRAINT %s ON DOMAIN",
+								  fmtId(coninfo->dobj.name));
+
+				dumpComment(fout, conprefix->data, qtypname,
+							tyinfo->dobj.namespace->dobj.name,
+							tyinfo->rolname,
+							coninfo->dobj.catId, 0, tyinfo->dobj.dumpId);
+				destroyPQExpBuffer(conprefix);
+				free(qtypname);
+			}
 		}
 	}
 	else
diff --git a/src/bin/pg_dump/pg_dump.h b/src/bin/pg_dump/pg_dump.h
index 39eef1d6617f4..dde85ed156cc8 100644
--- a/src/bin/pg_dump/pg_dump.h
+++ b/src/bin/pg_dump/pg_dump.h
@@ -222,7 +222,9 @@ typedef struct _typeInfo
 	bool		isDefined;		/* true if typisdefined */
 	/* If needed, we'll create a "shell type" entry for it; link that here: */
 	struct _shellTypeInfo *shellType;	/* shell-type entry, or NULL */
-	/* If it's a domain, we store links to its constraints here: */
+	/* If it's a domain, its not-null constraint is here: */
+	struct _constraintInfo *notnull;
+	/* If it's a domain, we store links to its CHECK constraints here: */
 	int			nDomChecks;
 	struct _constraintInfo *domChecks;
 } TypeInfo;
@@ -258,6 +260,8 @@ typedef struct _oprInfo
 	DumpableObject dobj;
 	const char *rolname;
 	char		oprkind;
+	Oid			oprleft;
+	Oid			oprright;
 	Oid			oprcode;
 } OprInfo;
 
@@ -271,12 +275,14 @@ typedef struct _accessMethodInfo
 typedef struct _opclassInfo
 {
 	DumpableObject dobj;
+	Oid			opcmethod;
 	const char *rolname;
 } OpclassInfo;
 
 typedef struct _opfamilyInfo
 {
 	DumpableObject dobj;
+	Oid			opfmethod;
 	const char *rolname;
 } OpfamilyInfo;
 
@@ -284,6 +290,7 @@ typedef struct _collInfo
 {
 	DumpableObject dobj;
 	const char *rolname;
+	int			collencoding;
 } CollInfo;
 
 typedef struct _convInfo
@@ -709,6 +716,7 @@ typedef struct _SubscriptionInfo
 	bool		subpasswordrequired;
 	bool		subrunasowner;
 	bool		subfailover;
+	bool		subretaindeadtuples;
 	char	   *subconninfo;
 	char	   *subslotname;
 	char	   *subsynccommit;
@@ -757,6 +765,7 @@ extern TableInfo *findTableByOid(Oid oid);
 extern TypeInfo *findTypeByOid(Oid oid);
 extern FuncInfo *findFuncByOid(Oid oid);
 extern OprInfo *findOprByOid(Oid oid);
+extern AccessMethodInfo *findAccessMethodByOid(Oid oid);
 extern CollInfo *findCollationByOid(Oid oid);
 extern NamespaceInfo *findNamespaceByOid(Oid oid);
 extern ExtensionInfo *findExtensionByOid(Oid oid);
diff --git a/src/bin/pg_dump/pg_dump_sort.c b/src/bin/pg_dump/pg_dump_sort.c
index 0b0977788f13d..a02da3e9652c1 100644
--- a/src/bin/pg_dump/pg_dump_sort.c
+++ b/src/bin/pg_dump/pg_dump_sort.c
@@ -76,10 +76,10 @@ enum dbObjectTypePriorities
 	PRIO_TABLE_ATTACH,
 	PRIO_DUMMY_TYPE,
 	PRIO_ATTRDEF,
-	PRIO_LARGE_OBJECT,
 	PRIO_PRE_DATA_BOUNDARY,		/* boundary! */
 	PRIO_TABLE_DATA,
 	PRIO_SEQUENCE_SET,
+	PRIO_LARGE_OBJECT,
 	PRIO_LARGE_OBJECT_DATA,
 	PRIO_STATISTICS_DATA_DATA,
 	PRIO_POST_DATA_BOUNDARY,	/* boundary! */
@@ -162,6 +162,8 @@ static DumpId postDataBoundId;
 
 
 static int	DOTypeNameCompare(const void *p1, const void *p2);
+static int	pgTypeNameCompare(Oid typid1, Oid typid2);
+static int	accessMethodNameCompare(Oid am1, Oid am2);
 static bool TopoSort(DumpableObject **objs,
 					 int numObjs,
 					 DumpableObject **ordering,
@@ -228,12 +230,39 @@ DOTypeNameCompare(const void *p1, const void *p2)
 	else if (obj2->namespace)
 		return 1;
 
-	/* Sort by name */
+	/*
+	 * Sort by name.  With a few exceptions, names here are single catalog
+	 * columns.  To get a fuller picture, grep pg_dump.c for "dobj.name = ".
+	 * Names here don't match "Name:" in plain format output, which is a
+	 * _tocEntry.tag.  For example, DumpableObject.name of a constraint is
+	 * pg_constraint.conname, but _tocEntry.tag of a constraint is relname and
+	 * conname joined with a space.
+	 */
 	cmpval = strcmp(obj1->name, obj2->name);
 	if (cmpval != 0)
 		return cmpval;
 
-	/* To have a stable sort order, break ties for some object types */
+	/*
+	 * Sort by type.  This helps types that share a type priority without
+	 * sharing a unique name constraint, e.g. opclass and opfamily.
+	 */
+	cmpval = obj1->objType - obj2->objType;
+	if (cmpval != 0)
+		return cmpval;
+
+	/*
+	 * To have a stable sort order, break ties for some object types.  Most
+	 * catalogs have a natural key, e.g. pg_proc_proname_args_nsp_index. Where
+	 * the above "namespace" and "name" comparisons don't cover all natural
+	 * key columns, compare the rest here.
+	 *
+	 * The natural key usually refers to other catalogs by surrogate keys.
+	 * Hence, this translates each of those references to the natural key of
+	 * the referenced catalog.  That may descend through multiple levels of
+	 * catalog references.  For example, to sort by pg_proc.proargtypes,
+	 * descend to each pg_type and then further to its pg_namespace, for an
+	 * overall sort by (nspname, typname).
+	 */
 	if (obj1->objType == DO_FUNC || obj1->objType == DO_AGG)
 	{
 		FuncInfo   *fobj1 = *(FuncInfo *const *) p1;
@@ -246,22 +275,10 @@ DOTypeNameCompare(const void *p1, const void *p2)
 			return cmpval;
 		for (i = 0; i < fobj1->nargs; i++)
 		{
-			TypeInfo   *argtype1 = findTypeByOid(fobj1->argtypes[i]);
-			TypeInfo   *argtype2 = findTypeByOid(fobj2->argtypes[i]);
-
-			if (argtype1 && argtype2)
-			{
-				if (argtype1->dobj.namespace && argtype2->dobj.namespace)
-				{
-					cmpval = strcmp(argtype1->dobj.namespace->dobj.name,
-									argtype2->dobj.namespace->dobj.name);
-					if (cmpval != 0)
-						return cmpval;
-				}
-				cmpval = strcmp(argtype1->dobj.name, argtype2->dobj.name);
-				if (cmpval != 0)
-					return cmpval;
-			}
+			cmpval = pgTypeNameCompare(fobj1->argtypes[i],
+									   fobj2->argtypes[i]);
+			if (cmpval != 0)
+				return cmpval;
 		}
 	}
 	else if (obj1->objType == DO_OPERATOR)
@@ -273,6 +290,57 @@ DOTypeNameCompare(const void *p1, const void *p2)
 		cmpval = (oobj2->oprkind - oobj1->oprkind);
 		if (cmpval != 0)
 			return cmpval;
+		/* Within an oprkind, sort by argument type names */
+		cmpval = pgTypeNameCompare(oobj1->oprleft, oobj2->oprleft);
+		if (cmpval != 0)
+			return cmpval;
+		cmpval = pgTypeNameCompare(oobj1->oprright, oobj2->oprright);
+		if (cmpval != 0)
+			return cmpval;
+	}
+	else if (obj1->objType == DO_OPCLASS)
+	{
+		OpclassInfo *opcobj1 = *(OpclassInfo *const *) p1;
+		OpclassInfo *opcobj2 = *(OpclassInfo *const *) p2;
+
+		/* Sort by access method name, per pg_opclass_am_name_nsp_index */
+		cmpval = accessMethodNameCompare(opcobj1->opcmethod,
+										 opcobj2->opcmethod);
+		if (cmpval != 0)
+			return cmpval;
+	}
+	else if (obj1->objType == DO_OPFAMILY)
+	{
+		OpfamilyInfo *opfobj1 = *(OpfamilyInfo *const *) p1;
+		OpfamilyInfo *opfobj2 = *(OpfamilyInfo *const *) p2;
+
+		/* Sort by access method name, per pg_opfamily_am_name_nsp_index */
+		cmpval = accessMethodNameCompare(opfobj1->opfmethod,
+										 opfobj2->opfmethod);
+		if (cmpval != 0)
+			return cmpval;
+	}
+	else if (obj1->objType == DO_COLLATION)
+	{
+		CollInfo   *cobj1 = *(CollInfo *const *) p1;
+		CollInfo   *cobj2 = *(CollInfo *const *) p2;
+
+		/*
+		 * Sort by encoding, per pg_collation_name_enc_nsp_index. Technically,
+		 * this is not necessary, because wherever this changes dump order,
+		 * restoring the dump fails anyway.  CREATE COLLATION can't create a
+		 * tie for this to break, because it imposes restrictions to make
+		 * (nspname, collname) uniquely identify a collation within a given
+		 * DatabaseEncoding.  While pg_import_system_collations() can create a
+		 * tie, pg_dump+restore fails after
+		 * pg_import_system_collations('my_schema') does so. However, there's
+		 * little to gain by ignoring one natural key column on the basis of
+		 * those limitations elsewhere, so respect the full natural key like
+		 * we do for other object types.
+		 */
+		cmpval = cobj1->collencoding - cobj2->collencoding;
+		if (cmpval != 0)
+			return cmpval;
 	}
 	else if (obj1->objType == DO_ATTRDEF)
 	{
@@ -317,11 +385,143 @@ DOTypeNameCompare(const void *p1, const void *p2)
 		if (cmpval != 0)
 			return cmpval;
 	}
+	else if (obj1->objType == DO_CONSTRAINT)
+	{
+		ConstraintInfo *robj1 = *(ConstraintInfo *const *) p1;
+		ConstraintInfo *robj2 = *(ConstraintInfo *const *) p2;
+
+		/*
+		 * Sort domain constraints before table constraints, for consistency
+		 * with our decision to sort CREATE DOMAIN before CREATE TABLE.
+		 */
+		if (robj1->condomain)
+		{
+			if (robj2->condomain)
+			{
+				/* Sort by domain name (domain namespace was considered) */
+				cmpval = strcmp(robj1->condomain->dobj.name,
+								robj2->condomain->dobj.name);
+				if (cmpval != 0)
+					return cmpval;
+			}
+			else
+				return PRIO_TYPE - PRIO_TABLE;
+		}
+		else if (robj2->condomain)
+			return PRIO_TABLE - PRIO_TYPE;
+		else
+		{
+			/* Sort by table name (table namespace was considered already) */
+			cmpval = strcmp(robj1->contable->dobj.name,
+							robj2->contable->dobj.name);
+			if (cmpval != 0)
+				return cmpval;
+		}
+	}
+	else if (obj1->objType == DO_PUBLICATION_REL)
+	{
+		PublicationRelInfo *probj1 = *(PublicationRelInfo *const *) p1;
+		PublicationRelInfo *probj2 = *(PublicationRelInfo *const *) p2;
+
+		/* Sort by publication name, since (namespace, name) match the rel */
+		cmpval = strcmp(probj1->publication->dobj.name,
+						probj2->publication->dobj.name);
+		if (cmpval != 0)
+			return cmpval;
+	}
+	else if (obj1->objType == DO_PUBLICATION_TABLE_IN_SCHEMA)
+	{
+		PublicationSchemaInfo *psobj1 = *(PublicationSchemaInfo *const *) p1;
+		PublicationSchemaInfo *psobj2 = *(PublicationSchemaInfo *const *) p2;
+
+		/* Sort by publication name, since ->name is just nspname */
+		cmpval = strcmp(psobj1->publication->dobj.name,
+						psobj2->publication->dobj.name);
+		if (cmpval != 0)
+			return cmpval;
+	}
 
-	/* Usually shouldn't get here, but if we do, sort by OID */
+	/*
+	 * Shouldn't get here except after catalog corruption, but if we do, sort
+	 * by OID.  This may make logically-identical databases differ in the
+	 * order of objects in dump output.  Users will get spurious schema diffs.
+	 * Expect flaky failures of 002_pg_upgrade.pl test 'dump outputs from
+	 * original and restored regression databases match' if the regression
+	 * database contains objects allowing that test to reach here.  That's a
+	 * consequence of the test using "pg_restore -j", which doesn't fully
+	 * constrain OID assignment order.
+	 */
+	Assert(false);
 	return oidcmp(obj1->catId.oid, obj2->catId.oid);
 }
 
+/* Compare two OID-identified pg_type values by nspname, then by typname. */
+static int
+pgTypeNameCompare(Oid typid1, Oid typid2)
+{
+	TypeInfo   *typobj1;
+	TypeInfo   *typobj2;
+	int			cmpval;
+
+	if (typid1 == typid2)
+		return 0;
+
+	typobj1 = findTypeByOid(typid1);
+	typobj2 = findTypeByOid(typid2);
+
+	if (!typobj1 || !typobj2)
+	{
+		/*
+		 * getTypes() didn't find some OID.  Assume catalog corruption, e.g.
+		 * an oprright value without the corresponding OID in a pg_type row.
+		 * Report as "equal", so the caller uses the next available basis for
+		 * comparison, e.g. the next function argument.
+		 *
+		 * Unary operators have InvalidOid in oprleft (if oprkind='r') or in
+		 * oprright (if oprkind='l').  Caller already sorted by oprkind,
+		 * calling us only for like-kind operators.  Hence, "typid1 == typid2"
+		 * took care of InvalidOid.  (v14 removed postfix operator support.
+		 * Hence, when dumping from v14+, only oprleft can be InvalidOid.)
+		 */
+		Assert(false);
+		return 0;
+	}
+
+	if (!typobj1->dobj.namespace || !typobj2->dobj.namespace)
+		Assert(false);			/* catalog corruption */
+	else
+	{
+		cmpval = strcmp(typobj1->dobj.namespace->dobj.name,
+						typobj2->dobj.namespace->dobj.name);
+		if (cmpval != 0)
+			return cmpval;
+	}
+	return strcmp(typobj1->dobj.name, typobj2->dobj.name);
+}
+
+/* Compare two OID-identified pg_am values by amname. */
+static int
+accessMethodNameCompare(Oid am1, Oid am2)
+{
+	AccessMethodInfo *amobj1;
+	AccessMethodInfo *amobj2;
+
+	if (am1 == am2)
+		return 0;
+
+	amobj1 = findAccessMethodByOid(am1);
+	amobj2 = findAccessMethodByOid(am2);
+
+	if (!amobj1 || !amobj2)
+	{
+		/* catalog corruption: handle like pgTypeNameCompare() does */
+		Assert(false);
+		return 0;
+	}
+
+	return strcmp(amobj1->dobj.name, amobj2->dobj.name);
+}
+
 
 /*
  * Sort the given objects into a safe dump order using dependency
@@ -907,7 +1107,7 @@ repairTableAttrDefMultiLoop(DumpableObject *tableobj,
 }
 
 /*
- * CHECK constraints on domains work just like those on tables ...
+ * CHECK, NOT NULL constraints on domains work just like those on tables ...
  */
 static void
 repairDomainConstraintLoop(DumpableObject *domainobj,
@@ -1173,11 +1373,12 @@ repairDependencyLoop(DumpableObject **loop,
 		}
 	}
 
-	/* Domain and CHECK constraint */
+	/* Domain and CHECK or NOT NULL constraint */
 	if (nLoop == 2 &&
 		loop[0]->objType == DO_TYPE &&
 		loop[1]->objType == DO_CONSTRAINT &&
-		((ConstraintInfo *) loop[1])->contype == 'c' &&
+		(((ConstraintInfo *) loop[1])->contype == 'c' ||
+		 ((ConstraintInfo *) loop[1])->contype == 'n') &&
 		((ConstraintInfo *) loop[1])->condomain == (TypeInfo *) loop[0])
 	{
 		repairDomainConstraintLoop(loop[0], loop[1]);
@@ -1186,14 +1387,15 @@ repairDependencyLoop(DumpableObject **loop,
 	if (nLoop == 2 &&
 		loop[1]->objType == DO_TYPE &&
 		loop[0]->objType == DO_CONSTRAINT &&
-		((ConstraintInfo *) loop[0])->contype == 'c' &&
+		(((ConstraintInfo *) loop[0])->contype == 'c' ||
+		 ((ConstraintInfo *) loop[0])->contype == 'n') &&
 		((ConstraintInfo *) loop[0])->condomain == (TypeInfo *) loop[1])
 	{
 		repairDomainConstraintLoop(loop[1], loop[0]);
 		return;
 	}
 
-	/* Indirect loop involving domain and CHECK constraint */
+	/* Indirect loop involving domain and CHECK or NOT NULL constraint */
 	if (nLoop > 2)
 	{
 		for (i = 0; i < nLoop; i++)
@@ -1203,7 +1405,8 @@ repairDependencyLoop(DumpableObject **loop,
 				for (j = 0; j < nLoop; j++)
 				{
 					if (loop[j]->objType == DO_CONSTRAINT &&
-						((ConstraintInfo *) loop[j])->contype == 'c' &&
+						(((ConstraintInfo *) loop[j])->contype == 'c' ||
+						 ((ConstraintInfo *) loop[j])->contype == 'n') &&
 						((ConstraintInfo *) loop[j])->condomain == (TypeInfo *) loop[i])
 					{
 						repairDomainConstraintMultiLoop(loop[i], loop[j]);
diff --git a/src/bin/pg_dump/pg_dumpall.c b/src/bin/pg_dump/pg_dumpall.c
index 3cbcad65c5fb5..27aa1b656989c 100644
--- a/src/bin/pg_dump/pg_dumpall.c
+++ b/src/bin/pg_dump/pg_dumpall.c
@@ -65,10 +65,9 @@ static void dropTablespaces(PGconn *conn);
 static void dumpTablespaces(PGconn *conn);
 static void dropDBs(PGconn *conn);
 static void dumpUserConfig(PGconn *conn, const char *username);
-static void dumpDatabases(PGconn *conn, ArchiveFormat archDumpFormat);
+static void dumpDatabases(PGconn *conn);
 static void dumpTimestamp(const char *msg);
-static int	runPgDump(const char *dbname, const char *create_opts,
-					  char *dbfile, ArchiveFormat archDumpFormat);
+static int	runPgDump(const char *dbname, const char *create_opts);
 static void buildShSecLabels(PGconn *conn,
 							 const char *catalog_name, Oid objectId,
 							 const char *objtype, const char *objname,
@@ -77,7 +76,6 @@ static void executeCommand(PGconn *conn, const char *query);
 static void expand_dbname_patterns(PGconn *conn, SimpleStringList *patterns,
 								   SimpleStringList *names);
 static void read_dumpall_filters(const char *filename, SimpleStringList *pattern);
-static ArchiveFormat parseDumpFormat(const char *format);
 
 static char pg_dump_bin[MAXPGPATH];
 static PQExpBuffer pgdumpopts;
@@ -107,8 +105,6 @@ static int	no_subscriptions = 0;
 static int	no_toast_compression = 0;
 static int	no_unlogged_table_data = 0;
 static int	no_role_passwords = 0;
-static int	with_data = 0;
-static int	with_schema = 0;
 static int	with_statistics = 0;
 static int	server_version;
 static int	load_via_partition_root = 0;
@@ -150,7 +146,6 @@ main(int argc, char *argv[])
 		{"password", no_argument, NULL, 'W'},
 		{"no-privileges", no_argument, NULL, 'x'},
 		{"no-acl", no_argument, NULL, 'x'},
-		{"format", required_argument, NULL, 'F'},
 
 		/*
 		 * the following options don't have an equivalent short option letter
@@ -183,11 +178,9 @@ main(int argc, char *argv[])
 		{"no-sync", no_argument, NULL, 4},
 		{"no-toast-compression", no_argument, &no_toast_compression, 1},
 		{"no-unlogged-table-data", no_argument, &no_unlogged_table_data, 1},
-		{"with-data", no_argument, &with_data, 1},
-		{"with-schema", no_argument, &with_schema, 1},
-		{"with-statistics", no_argument, &with_statistics, 1},
 		{"on-conflict-do-nothing", no_argument, &on_conflict_do_nothing, 1},
 		{"rows-per-insert", required_argument, NULL, 7},
+		{"statistics", no_argument, &with_statistics, 1},
 		{"statistics-only", no_argument, &statistics_only, 1},
 		{"filter", required_argument, NULL, 8},
 		{"sequence-data", no_argument, &sequence_data, 1},
@@ -201,8 +194,6 @@ main(int argc, char *argv[])
 	char	   *pgdb = NULL;
 	char	   *use_role = NULL;
 	const char *dumpencoding = NULL;
-	ArchiveFormat archDumpFormat = archNull;
-	const char *formatName = "p";
 	trivalue	prompt_password = TRI_DEFAULT;
 	bool		data_only = false;
 	bool		globals_only = false;
@@ -252,7 +243,7 @@ main(int argc, char *argv[])
 
 	pgdumpopts = createPQExpBuffer();
 
-	while ((c = getopt_long(argc, argv, "acd:E:f:F:gh:l:Op:rsS:tU:vwWx", long_options, &optindex)) != -1)
+	while ((c = getopt_long(argc, argv, "acd:E:f:gh:l:Op:rsS:tU:vwWx", long_options, &optindex)) != -1)
 	{
 		switch (c)
 		{
@@ -280,9 +271,7 @@ main(int argc, char *argv[])
 				appendPQExpBufferStr(pgdumpopts, " -f ");
 				appendShellString(pgdumpopts, filename);
 				break;
-			case 'F':
-				formatName = pg_strdup(optarg);
-				break;
+
 			case 'g':
 				globals_only = true;
 				break;
@@ -431,21 +420,6 @@ main(int argc, char *argv[])
 		exit_nicely(1);
 	}
 
-	/* Get format for dump. */
-	archDumpFormat = parseDumpFormat(formatName);
-
-	/*
-	 * If a non-plain format is specified, a file name is also required as the
-	 * path to the main directory.
-	 */
-	if (archDumpFormat != archNull &&
-		(!filename || strcmp(filename, "") == 0))
-	{
-		pg_log_error("option -F/--format=d|c|t requires option -f/--file");
-		pg_log_error_hint("Try \"%s --help\" for more information.", progname);
-		exit_nicely(1);
-	}
-
 	/*
 	 * If password values are not required in the dump, switch to using
 	 * pg_roles which is equally useful, just more likely to have unrestricted
@@ -497,12 +471,8 @@ main(int argc, char *argv[])
 		appendPQExpBufferStr(pgdumpopts, " --no-toast-compression");
 	if (no_unlogged_table_data)
 		appendPQExpBufferStr(pgdumpopts, " --no-unlogged-table-data");
-	if (with_data)
-		appendPQExpBufferStr(pgdumpopts, " --with-data");
-	if (with_schema)
-		appendPQExpBufferStr(pgdumpopts, " --with-schema");
 	if (with_statistics)
-		appendPQExpBufferStr(pgdumpopts, " --with-statistics");
+		appendPQExpBufferStr(pgdumpopts, " --statistics");
 	if (on_conflict_do_nothing)
 		appendPQExpBufferStr(pgdumpopts, " --on-conflict-do-nothing");
 	if (statistics_only)
@@ -510,33 +480,6 @@ main(int argc, char *argv[])
 	if (sequence_data)
 		appendPQExpBufferStr(pgdumpopts, " --sequence-data");
 
-	/*
-	 * Open the output file if required, otherwise use stdout.  If required,
-	 * then create new directory and global.dat file.
-	 */
-	if (archDumpFormat != archNull)
-	{
-		char		global_path[MAXPGPATH];
-
-		/* Create new directory or accept the empty existing directory. */
-		create_or_open_dir(filename);
-
-		snprintf(global_path, MAXPGPATH, "%s/global.dat", filename);
-
-		OPF = fopen(global_path, PG_BINARY_W);
-		if (!OPF)
-			pg_fatal("could not open file \"%s\": %m", global_path);
-	}
-	else if (filename)
-	{
-		OPF = fopen(filename, PG_BINARY_W);
-		if (!OPF)
-			pg_fatal("could not open output file \"%s\": %m",
-					 filename);
-	}
-	else
-		OPF = stdout;
-
 	/*
 	 * If there was a database specified on the command line, use that,
 	 * otherwise try to connect to database "postgres", and failing that
@@ -576,6 +519,19 @@ main(int argc, char *argv[])
 	expand_dbname_patterns(conn, &database_exclude_patterns,
 						   &database_exclude_names);
 
+	/*
+	 * Open the output file if required, otherwise use stdout
+	 */
+	if (filename)
+	{
+		OPF = fopen(filename, PG_BINARY_W);
+		if (!OPF)
+			pg_fatal("could not open output file \"%s\": %m",
+					 filename);
+	}
+	else
+		OPF = stdout;
+
 	/*
 	 * Set the client encoding if requested.
 	 */
@@ -632,7 +588,7 @@ main(int argc, char *argv[])
 		fprintf(OPF, "SET escape_string_warning = off;\n");
 	fprintf(OPF, "\n");
 
-	if (!data_only)
+	if (!data_only && !statistics_only && !no_schema)
 	{
 		/*
 		 * If asked to --clean, do that first.  We can avoid detailed
@@ -675,7 +631,7 @@ main(int argc, char *argv[])
 	}
 
 	if (!globals_only && !roles_only && !tablespaces_only)
-		dumpDatabases(conn, archDumpFormat);
+		dumpDatabases(conn);
 
 	PQfinish(conn);
 
@@ -688,7 +644,7 @@ main(int argc, char *argv[])
 		fclose(OPF);
 
 		/* sync the resulting file, errors are not fatal */
-		if (dosync && (archDumpFormat == archNull))
+		if (dosync)
 			(void) fsync_fname(filename, false);
 	}
 
@@ -699,14 +655,12 @@ main(int argc, char *argv[])
 static void
 help(void)
 {
-	printf(_("%s exports a PostgreSQL database cluster as an SQL script or to other formats.\n\n"), progname);
+	printf(_("%s exports a PostgreSQL database cluster as an SQL script.\n\n"), progname);
 	printf(_("Usage:\n"));
 	printf(_("  %s [OPTION]...\n"), progname);
 
 	printf(_("\nGeneral options:\n"));
 	printf(_("  -f, --file=FILENAME          output file name\n"));
-	printf(_("  -F, --format=c|d|t|p         output file format (custom, directory, tar,\n"
-			 "                               plain text (default))\n"));
 	printf(_("  -v, --verbose                verbose mode\n"));
 	printf(_("  -V, --version                output version information, then exit\n"));
 	printf(_("  --lock-wait-timeout=TIMEOUT  fail after waiting TIMEOUT for a table lock\n"));
@@ -750,13 +704,11 @@ help(void)
 	printf(_("  --quote-all-identifiers      quote all identifiers, even if not key words\n"));
 	printf(_("  --rows-per-insert=NROWS      number of rows per INSERT; implies --inserts\n"));
 	printf(_("  --sequence-data              include sequence data in dump\n"));
+	printf(_("  --statistics                 dump the statistics\n"));
 	printf(_("  --statistics-only            dump only the statistics, not schema or data\n"));
 	printf(_("  --use-set-session-authorization\n"
 			 "                               use SET SESSION AUTHORIZATION commands instead of\n"
 			 "                               ALTER OWNER commands to set ownership\n"));
-	printf(_("  --with-data                  dump the data\n"));
-	printf(_("  --with-schema                dump the schema\n"));
-	printf(_("  --with-statistics            dump the statistics\n"));
 
 	printf(_("\nConnection options:\n"));
 	printf(_("  -d, --dbname=CONNSTR     connect using connection string\n"));
@@ -1013,6 +965,9 @@ dumpRoles(PGconn *conn)
 	 * We do it this way because config settings for roles could mention the
 	 * names of other roles.
 	 */
+	if (PQntuples(res) > 0)
+		fprintf(OPF, "\n--\n-- User Configurations\n--\n");
+
 	for (i = 0; i < PQntuples(res); i++)
 		dumpUserConfig(conn, PQgetvalue(res, i, i_rolname));
 
@@ -1526,7 +1481,6 @@ dumpUserConfig(PGconn *conn, const char *username)
 {
 	PQExpBuffer buf = createPQExpBuffer();
 	PGresult   *res;
-	static bool header_done = false;
 
 	printfPQExpBuffer(buf, "SELECT unnest(setconfig) FROM pg_db_role_setting "
 					  "WHERE setdatabase = 0 AND setrole = "
@@ -1538,13 +1492,7 @@ dumpUserConfig(PGconn *conn, const char *username)
 	res = executeQuery(conn, buf->data);
 
 	if (PQntuples(res) > 0)
-	{
-		if (!header_done)
-			fprintf(OPF, "\n--\n-- User Configurations\n--\n");
-		header_done = true;
-
 		fprintf(OPF, "\n--\n-- User Config \"%s\"\n--\n\n", username);
-	}
 
 	for (int i = 0; i < PQntuples(res); i++)
 	{
@@ -1618,13 +1566,10 @@ expand_dbname_patterns(PGconn *conn,
  * Dump contents of databases.
  */
 static void
-dumpDatabases(PGconn *conn, ArchiveFormat archDumpFormat)
+dumpDatabases(PGconn *conn)
 {
 	PGresult   *res;
 	int			i;
-	char		db_subdir[MAXPGPATH];
-	char		dbfilepath[MAXPGPATH];
-	FILE	   *map_file = NULL;
 
 	/*
 	 * Skip databases marked not datallowconn, since we'd be unable to connect
@@ -1638,42 +1583,18 @@ dumpDatabases(PGconn *conn, ArchiveFormat archDumpFormat)
 	 * doesn't have some failure mode with --clean.
 	 */
 	res = executeQuery(conn,
-					   "SELECT datname, oid "
+					   "SELECT datname "
 					   "FROM pg_database d "
 					   "WHERE datallowconn AND datconnlimit != -2 "
 					   "ORDER BY (datname <> 'template1'), datname");
 
-	if (archDumpFormat == archNull && PQntuples(res) > 0)
+	if (PQntuples(res) > 0)
 		fprintf(OPF, "--\n-- Databases\n--\n\n");
 
-	/*
-	 * If directory/tar/custom format is specified, create a subdirectory
-	 * under the main directory and each database dump file or subdirectory
-	 * will be created in that subdirectory by pg_dump.
-	 */
-	if (archDumpFormat != archNull)
-	{
-		char		map_file_path[MAXPGPATH];
-
-		snprintf(db_subdir, MAXPGPATH, "%s/databases", filename);
-
-		/* Create a subdirectory with 'databases' name under main directory. */
-		if (mkdir(db_subdir, pg_dir_create_mode) != 0)
-			pg_fatal("could not create directory \"%s\": %m", db_subdir);
-
-		snprintf(map_file_path, MAXPGPATH, "%s/map.dat", filename);
-
-		/* Create a map file (to store dboid and dbname) */
-		map_file = fopen(map_file_path, PG_BINARY_W);
-		if (!map_file)
-			pg_fatal("could not open file \"%s\": %m", map_file_path);
-	}
-
 	for (i = 0; i < PQntuples(res); i++)
 	{
 		char	   *dbname = PQgetvalue(res, i, 0);
-		char	   *oid = PQgetvalue(res, i, 1);
-		const char *create_opts = "";
+		const char *create_opts;
 		int			ret;
 
 		/* Skip template0, even if it's not marked !datallowconn. */
@@ -1687,27 +1608,9 @@ dumpDatabases(PGconn *conn, ArchiveFormat archDumpFormat)
 			continue;
 		}
 
-		/*
-		 * If this is not a plain format dump, then append dboid and dbname to
-		 * the map.dat file.
-		 */
-		if (archDumpFormat != archNull)
-		{
-			if (archDumpFormat == archCustom)
-				snprintf(dbfilepath, MAXPGPATH, "\"%s\"/\"%s\".dmp", db_subdir, oid);
-			else if (archDumpFormat == archTar)
-				snprintf(dbfilepath, MAXPGPATH, "\"%s\"/\"%s\".tar", db_subdir, oid);
-			else
-				snprintf(dbfilepath, MAXPGPATH, "\"%s\"/\"%s\"", db_subdir, oid);
-
-			/* Put one line entry for dboid and dbname in map file. */
-			fprintf(map_file, "%s %s\n", oid, dbname);
-		}
-
 		pg_log_info("dumping database \"%s\"", dbname);
 
-		if (archDumpFormat == archNull)
-			fprintf(OPF, "--\n-- Database \"%s\" dump\n--\n\n", dbname);
+		fprintf(OPF, "--\n-- Database \"%s\" dump\n--\n\n", dbname);
 
 		/*
 		 * We assume that "template1" and "postgres" already exist in the
@@ -1721,9 +1624,12 @@ dumpDatabases(PGconn *conn, ArchiveFormat archDumpFormat)
 		{
 			if (output_clean)
 				create_opts = "--clean --create";
-			/* Since pg_dump won't emit a \connect command, we must */
-			else if (archDumpFormat == archNull)
+			else
+			{
+				create_opts = "";
+				/* Since pg_dump won't emit a \connect command, we must */
 				fprintf(OPF, "\\connect %s\n\n", dbname);
+			}
 		}
 		else
 			create_opts = "--create";
@@ -1731,30 +1637,19 @@ dumpDatabases(PGconn *conn, ArchiveFormat archDumpFormat)
 		if (filename)
 			fclose(OPF);
 
-		ret = runPgDump(dbname, create_opts, dbfilepath, archDumpFormat);
+		ret = runPgDump(dbname, create_opts);
 		if (ret != 0)
 			pg_fatal("pg_dump failed on database \"%s\", exiting", dbname);
 
 		if (filename)
 		{
-			char		global_path[MAXPGPATH];
-
-			if (archDumpFormat != archNull)
-				snprintf(global_path, MAXPGPATH, "%s/global.dat", filename);
-			else
-				snprintf(global_path, MAXPGPATH, "%s", filename);
-
-			OPF = fopen(global_path, PG_BINARY_A);
+			OPF = fopen(filename, PG_BINARY_A);
 			if (!OPF)
 				pg_fatal("could not re-open the output file \"%s\": %m",
-						 global_path);
+						 filename);
 		}
 	}
 
-	/* Close map file */
-	if (archDumpFormat != archNull)
-		fclose(map_file);
-
 	PQclear(res);
 }
 
@@ -1764,8 +1659,7 @@ dumpDatabases(PGconn *conn, ArchiveFormat archDumpFormat)
  * Run pg_dump on dbname, with specified options.
  */
 static int
-runPgDump(const char *dbname, const char *create_opts, char *dbfile,
-		  ArchiveFormat archDumpFormat)
+runPgDump(const char *dbname, const char *create_opts)
 {
 	PQExpBufferData connstrbuf;
 	PQExpBufferData cmd;
@@ -1774,36 +1668,17 @@ runPgDump(const char *dbname, const char *create_opts, char *dbfile,
 	initPQExpBuffer(&connstrbuf);
 	initPQExpBuffer(&cmd);
 
+	printfPQExpBuffer(&cmd, "\"%s\" %s %s", pg_dump_bin,
+					  pgdumpopts->data, create_opts);
+
 	/*
-	 * If this is not a plain format dump, then append file name and dump
-	 * format to the pg_dump command to get archive dump.
+	 * If we have a filename, use the undocumented plain-append pg_dump
+	 * format.
 	 */
-	if (archDumpFormat != archNull)
-	{
-		printfPQExpBuffer(&cmd, "\"%s\" -f %s %s", pg_dump_bin,
-						  dbfile, create_opts);
-
-		if (archDumpFormat == archDirectory)
-			appendPQExpBufferStr(&cmd, "  --format=directory ");
-		else if (archDumpFormat == archCustom)
-			appendPQExpBufferStr(&cmd, "  --format=custom ");
-		else if (archDumpFormat == archTar)
-			appendPQExpBufferStr(&cmd, "  --format=tar ");
-	}
+	if (filename)
+		appendPQExpBufferStr(&cmd, " -Fa ");
 	else
-	{
-		printfPQExpBuffer(&cmd, "\"%s\" %s %s", pg_dump_bin,
-						  pgdumpopts->data, create_opts);
-
-		/*
-		 * If we have a filename, use the undocumented plain-append pg_dump
-		 * format.
-		 */
-		if (filename)
-			appendPQExpBufferStr(&cmd, " -Fa ");
-		else
-			appendPQExpBufferStr(&cmd, " -Fp ");
-	}
+		appendPQExpBufferStr(&cmd, " -Fp ");
 
 	/*
 	 * Append the database name to the already-constructed stem of connection
@@ -1948,36 +1823,3 @@ read_dumpall_filters(const char *filename, SimpleStringList *pattern)
 
 	filter_free(&fstate);
 }
-
-/*
- * parseDumpFormat
- *
- * This will validate dump formats.
- */
-static ArchiveFormat
-parseDumpFormat(const char *format)
-{
-	ArchiveFormat archDumpFormat;
-
-	if (pg_strcasecmp(format, "c") == 0)
-		archDumpFormat = archCustom;
-	else if (pg_strcasecmp(format, "custom") == 0)
-		archDumpFormat = archCustom;
-	else if (pg_strcasecmp(format, "d") == 0)
-		archDumpFormat = archDirectory;
-	else if (pg_strcasecmp(format, "directory") == 0)
-		archDumpFormat = archDirectory;
-	else if (pg_strcasecmp(format, "p") == 0)
-		archDumpFormat = archNull;
-	else if (pg_strcasecmp(format, "plain") == 0)
-		archDumpFormat = archNull;
-	else if (pg_strcasecmp(format, "t") == 0)
-		archDumpFormat = archTar;
-	else if (pg_strcasecmp(format, "tar") == 0)
-		archDumpFormat = archTar;
-	else
-		pg_fatal("unrecognized output format \"%s\"; please specify \"c\", \"d\", \"p\", or \"t\"",
-				 format);
-
-	return archDumpFormat;
-}
diff --git a/src/bin/pg_dump/pg_restore.c b/src/bin/pg_dump/pg_restore.c
index 6ef789cb06d63..6c129278bc52b 100644
--- a/src/bin/pg_dump/pg_restore.c
+++ b/src/bin/pg_dump/pg_restore.c
@@ -2,7 +2,7 @@
  *
  * pg_restore.c
  *	pg_restore is an utility extracting postgres database definitions
- *	from a backup archive created by pg_dump/pg_dumpall using the archiver
+ *	from a backup archive created by pg_dump using the archiver
  *	interface.
  *
  *	pg_restore will read the backup archive and
@@ -41,15 +41,11 @@
 #include "postgres_fe.h"
 
 #include <ctype.h>
-#include <sys/stat.h>
 #ifdef HAVE_TERMIOS_H
 #include <termios.h>
 #endif
 
-#include "common/string.h"
-#include "connectdb.h"
 #include "fe_utils/option_utils.h"
-#include "fe_utils/string_utils.h"
 #include "filter.h"
 #include "getopt_long.h"
 #include "parallel.h"
@@ -57,43 +53,18 @@
 
 static void usage(const char *progname);
 static void read_restore_filters(const char *filename, RestoreOptions *opts);
-static bool file_exists_in_directory(const char *dir, const char *filename);
-static int	restore_one_database(const char *inputFileSpec, RestoreOptions *opts,
-								 int numWorkers, bool append_data, int num);
-static int	read_one_statement(StringInfo inBuf, FILE *pfile);
-static int	restore_all_databases(PGconn *conn, const char *dumpdirpath,
-								  SimpleStringList db_exclude_patterns, RestoreOptions *opts, int numWorkers);
-static int	process_global_sql_commands(PGconn *conn, const char *dumpdirpath,
-										const char *outfile);
-static void copy_or_print_global_file(const char *outfile, FILE *pfile);
-static int	get_dbnames_list_to_restore(PGconn *conn,
-										SimplePtrList *dbname_oid_list,
-										SimpleStringList db_exclude_patterns);
-static int	get_dbname_oid_list_from_mfile(const char *dumpdirpath,
-										   SimplePtrList *dbname_oid_list);
-
-/*
- * Stores a database OID and the corresponding name.
- */
-typedef struct DbOidName
-{
-	Oid			oid;
-	char		str[FLEXIBLE_ARRAY_MEMBER]; /* null-terminated string here */
-} DbOidName;
-
 
 int
 main(int argc, char **argv)
 {
 	RestoreOptions *opts;
 	int			c;
+	int			exit_code;
 	int			numWorkers = 1;
+	Archive    *AH;
 	char	   *inputFileSpec;
 	bool		data_only = false;
 	bool		schema_only = false;
-	int			n_errors = 0;
-	bool		globals_only = false;
-	SimpleStringList db_exclude_patterns = {NULL, NULL};
 	static int	disable_triggers = 0;
 	static int	enable_row_security = 0;
 	static int	if_exists = 0;
@@ -111,15 +82,12 @@ main(int argc, char **argv)
 	static int	no_subscriptions = 0;
 	static int	strict_names = 0;
 	static int	statistics_only = 0;
-	static int	with_data = 0;
-	static int	with_schema = 0;
 	static int	with_statistics = 0;
 
 	struct option cmdopts[] = {
 		{"clean", 0, NULL, 'c'},
 		{"create", 0, NULL, 'C'},
 		{"data-only", 0, NULL, 'a'},
-		{"globals-only", 0, NULL, 'g'},
 		{"dbname", 1, NULL, 'd'},
 		{"exit-on-error", 0, NULL, 'e'},
 		{"exclude-schema", 1, NULL, 'N'},
@@ -169,12 +137,9 @@ main(int argc, char **argv)
 		{"no-security-labels", no_argument, &no_security_labels, 1},
 		{"no-subscriptions", no_argument, &no_subscriptions, 1},
 		{"no-statistics", no_argument, &no_statistics, 1},
-		{"with-data", no_argument, &with_data, 1},
-		{"with-schema", no_argument, &with_schema, 1},
-		{"with-statistics", no_argument, &with_statistics, 1},
+		{"statistics", no_argument, &with_statistics, 1},
 		{"statistics-only", no_argument, &statistics_only, 1},
 		{"filter", required_argument, NULL, 4},
-		{"exclude-database", required_argument, NULL, 6},
 
 		{NULL, 0, NULL, 0}
 	};
@@ -203,7 +168,7 @@ main(int argc, char **argv)
 		}
 	}
 
-	while ((c = getopt_long(argc, argv, "acCd:ef:F:gh:I:j:lL:n:N:Op:P:RsS:t:T:U:vwWx1",
+	while ((c = getopt_long(argc, argv, "acCd:ef:F:h:I:j:lL:n:N:Op:P:RsS:t:T:U:vwWx1",
 							cmdopts, NULL)) != -1)
 	{
 		switch (c)
@@ -230,14 +195,11 @@ main(int argc, char **argv)
 				if (strlen(optarg) != 0)
 					opts->formatName = pg_strdup(optarg);
 				break;
-			case 'g':
-				/* restore only global.dat file from directory */
-				globals_only = true;
-				break;
 			case 'h':
 				if (strlen(optarg) != 0)
 					opts->cparams.pghost = pg_strdup(optarg);
 				break;
+
 			case 'j':			/* number of restore jobs */
 				if (!option_parse_int(optarg, "-j/--jobs", 1,
 									  PG_MAX_JOBS,
@@ -352,9 +314,6 @@ main(int argc, char **argv)
 					exit(1);
 				opts->exit_on_error = true;
 				break;
-			case 6:				/* database patterns to skip */
-				simple_string_list_append(&db_exclude_patterns, optarg);
-				break;
 
 			default:
 				/* getopt_long already emitted a complaint */
@@ -382,13 +341,6 @@ main(int argc, char **argv)
 	if (!opts->cparams.dbname && !opts->filename && !opts->tocSummary)
 		pg_fatal("one of -d/--dbname and -f/--file must be specified");
 
-	if (db_exclude_patterns.head != NULL && globals_only)
-	{
-		pg_log_error("option --exclude-database cannot be used together with -g/--globals-only");
-		pg_log_error_hint("Try \"%s --help\" for more information.", progname);
-		exit_nicely(1);
-	}
-
 	/* Should get at most one of -d and -f, else user is confused */
 	if (opts->cparams.dbname)
 	{
@@ -417,13 +369,17 @@ main(int argc, char **argv)
 	if (statistics_only && no_statistics)
 		pg_fatal("options --statistics-only and --no-statistics cannot be used together");
 
-	/* reject conflicting "with-" and "no-" options */
-	if (with_data && no_data)
-		pg_fatal("options --with-data and --no-data cannot be used together");
-	if (with_schema && no_schema)
-		pg_fatal("options --with-schema and --no-schema cannot be used together");
+	/* reject conflicting "no-" options */
 	if (with_statistics && no_statistics)
-		pg_fatal("options --with-statistics and --no-statistics cannot be used together");
+		pg_fatal("options --statistics and --no-statistics cannot be used together");
+
+	/* reject conflicting "only-" options */
+	if (data_only && with_statistics)
+		pg_fatal("options %s and %s cannot be used together",
+				 "-a/--data-only", "--statistics");
+	if (schema_only && with_statistics)
+		pg_fatal("options %s and %s cannot be used together",
+				 "-s/--schema-only", "--statistics");
 
 	if (data_only && opts->dropSchema)
 		pg_fatal("options -c/--clean and -a/--data-only cannot be used together");
@@ -443,16 +399,14 @@ main(int argc, char **argv)
 		pg_fatal("cannot specify both --single-transaction and multiple jobs");
 
 	/*
-	 * Set derivative flags. An "-only" option may be overridden by an
-	 * explicit "with-" option; e.g. "--schema-only --with-statistics" will
-	 * include schema and statistics. Other ambiguous or nonsensical
-	 * combinations, e.g. "--schema-only --no-schema", will have already
-	 * caused an error in one of the checks above.
+	 * Set derivative flags. Ambiguous or nonsensical combinations, e.g.
+	 * "--schema-only --no-schema", will have already caused an error in one
+	 * of the checks above.
 	 */
 	opts->dumpData = ((opts->dumpData && !schema_only && !statistics_only) ||
-					  (data_only || with_data)) && !no_data;
+					  data_only) && !no_data;
 	opts->dumpSchema = ((opts->dumpSchema && !data_only && !statistics_only) ||
-						(schema_only || with_schema)) && !no_schema;
+						schema_only) && !no_schema;
 	opts->dumpStatistics = ((opts->dumpStatistics && !schema_only && !data_only) ||
 							(statistics_only || with_statistics)) && !no_statistics;
 
@@ -496,114 +450,6 @@ main(int argc, char **argv)
 					 opts->formatName);
 	}
 
-	/*
-	 * If toc.dat file is not present in the current path, then check for
-	 * global.dat.  If global.dat file is present, then restore all the
-	 * databases from map.dat (if it exists), but skip restoring those
-	 * matching --exclude-database patterns.
-	 */
-	if (inputFileSpec != NULL && !file_exists_in_directory(inputFileSpec, "toc.dat") &&
-		file_exists_in_directory(inputFileSpec, "global.dat"))
-	{
-		PGconn	   *conn = NULL;	/* Connection to restore global sql
-									 * commands. */
-
-		/*
-		 * Can only use --list or --use-list options with a single database
-		 * dump.
-		 */
-		if (opts->tocSummary)
-			pg_fatal("option -l/--list cannot be used when restoring an archive created by pg_dumpall");
-		else if (opts->tocFile)
-			pg_fatal("option -L/--use-list cannot be used when restoring an archive created by pg_dumpall");
-
-		/*
-		 * To restore from a pg_dumpall archive, -C (create database) option
-		 * must be specified unless we are only restoring globals.
-		 */
-		if (!globals_only && opts->createDB != 1)
-		{
-			pg_log_error("option -C/--create must be specified when restoring an archive created by pg_dumpall");
-			pg_log_error_hint("Try \"%s --help\" for more information.", progname);
-			pg_log_error_hint("Individual databases can be restored using their specific archives.");
-			exit_nicely(1);
-		}
-
-		/*
-		 * Connect to the database to execute global sql commands from
-		 * global.dat file.
-		 */
-		if (opts->cparams.dbname)
-		{
-			conn = ConnectDatabase(opts->cparams.dbname, NULL, opts->cparams.pghost,
-								   opts->cparams.pgport, opts->cparams.username, TRI_DEFAULT,
-								   false, progname, NULL, NULL, NULL, NULL);
-
-
-			if (!conn)
-				pg_fatal("could not connect to database \"%s\"", opts->cparams.dbname);
-		}
-
-		/* If globals-only, then return from here. */
-		if (globals_only)
-		{
-			/*
-			 * Open global.dat file and execute/append all the global sql
-			 * commands.
-			 */
-			n_errors = process_global_sql_commands(conn, inputFileSpec,
-												   opts->filename);
-
-			if (conn)
-				PQfinish(conn);
-
-			pg_log_info("database restoring skipped because option -g/--globals-only was specified");
-		}
-		else
-		{
-			/* Now restore all the databases from map.dat */
-			n_errors = restore_all_databases(conn, inputFileSpec, db_exclude_patterns,
-											 opts, numWorkers);
-		}
-
-		/* Free db pattern list. */
-		simple_string_list_destroy(&db_exclude_patterns);
-	}
-	else						/* process if global.dat file does not exist. */
-	{
-		if (db_exclude_patterns.head != NULL)
-			pg_fatal("option --exclude-database can be used only when restoring an archive created by pg_dumpall");
-
-		if (globals_only)
-			pg_fatal("option -g/--globals-only can be used only when restoring an archive created by pg_dumpall");
-
-		n_errors = restore_one_database(inputFileSpec, opts, numWorkers, false, 0);
-	}
-
-	/* Done, print a summary of ignored errors during restore. */
-	if (n_errors)
-	{
-		pg_log_warning("errors ignored on restore: %d", n_errors);
-		return 1;
-	}
-
-	return 0;
-}
-
-/*
- * restore_one_database
- *
- * This will restore one database using toc.dat file.
- *
- * returns the number of errors while doing restore.
- */
-static int
-restore_one_database(const char *inputFileSpec, RestoreOptions *opts,
-					 int numWorkers, bool append_data, int num)
-{
-	Archive    *AH;
-	int			n_errors;
-
 	AH = OpenArchive(inputFileSpec, opts->format);
 
 	SetArchiveOptions(AH, NULL, opts);
@@ -611,15 +457,9 @@ restore_one_database(const char *inputFileSpec, RestoreOptions *opts,
 	/*
 	 * We don't have a connection yet but that doesn't matter. The connection
 	 * is initialized to NULL and if we terminate through exit_nicely() while
-	 * it's still NULL, the cleanup function will just be a no-op. If we are
-	 * restoring multiple databases, then only update AX handle for cleanup as
-	 * the previous entry was already in the array and we had closed previous
-	 * connection, so we can use the same array slot.
+	 * it's still NULL, the cleanup function will just be a no-op.
 	 */
-	if (!append_data || num == 0)
-		on_exit_close_archive(AH);
-	else
-		replace_on_exit_close_archive(AH);
+	on_exit_close_archive(AH);
 
 	/* Let the archiver know how noisy to be */
 	AH->verbose = opts->verbose;
@@ -639,21 +479,25 @@ restore_one_database(const char *inputFileSpec, RestoreOptions *opts,
 	else
 	{
 		ProcessArchiveRestoreOptions(AH);
-		RestoreArchive(AH, append_data);
+		RestoreArchive(AH);
 	}
 
-	n_errors = AH->n_errors;
+	/* done, print a summary of ignored errors */
+	if (AH->n_errors)
+		pg_log_warning("errors ignored on restore: %d", AH->n_errors);
 
 	/* AH may be freed in CloseArchive? */
+	exit_code = AH->n_errors ? 1 : 0;
+
 	CloseArchive(AH);
 
-	return n_errors;
+	return exit_code;
 }
 
 static void
 usage(const char *progname)
 {
-	printf(_("%s restores PostgreSQL databases from archives created by pg_dump or pg_dumpall.\n\n"), progname);
+	printf(_("%s restores a PostgreSQL database from an archive created by pg_dump.\n\n"), progname);
 	printf(_("Usage:\n"));
 	printf(_("  %s [OPTION]... [FILE]\n"), progname);
 
@@ -671,7 +515,6 @@ usage(const char *progname)
 	printf(_("  -c, --clean                  clean (drop) database objects before recreating\n"));
 	printf(_("  -C, --create                 create the target database\n"));
 	printf(_("  -e, --exit-on-error          exit on error, default is to continue\n"));
-	printf(_("  -g, --globals-only           restore only global objects, no databases\n"));
 	printf(_("  -I, --index=NAME             restore named index\n"));
 	printf(_("  -j, --jobs=NUM               use this many parallel jobs to restore\n"));
 	printf(_("  -L, --use-list=FILENAME      use table of contents from this file for\n"
@@ -688,7 +531,6 @@ usage(const char *progname)
 	printf(_("  -1, --single-transaction     restore as a single transaction\n"));
 	printf(_("  --disable-triggers           disable triggers during data-only restore\n"));
 	printf(_("  --enable-row-security        enable row security\n"));
-	printf(_("  --exclude-database=PATTERN   do not restore the specified database(s)\n"));
 	printf(_("  --filter=FILENAME            restore or skip objects based on expressions\n"
 			 "                               in FILENAME\n"));
 	printf(_("  --if-exists                  use IF EXISTS when dropping objects\n"));
@@ -705,6 +547,7 @@ usage(const char *progname)
 	printf(_("  --no-table-access-method     do not restore table access methods\n"));
 	printf(_("  --no-tablespaces             do not restore tablespace assignments\n"));
 	printf(_("  --section=SECTION            restore named section (pre-data, data, or post-data)\n"));
+	printf(_("  --statistics                 restore the statistics\n"));
 	printf(_("  --statistics-only            restore only the statistics, not schema or data\n"));
 	printf(_("  --strict-names               require table and/or schema include patterns to\n"
 			 "                               match at least one entity each\n"));
@@ -712,9 +555,6 @@ usage(const char *progname)
 	printf(_("  --use-set-session-authorization\n"
 			 "                               use SET SESSION AUTHORIZATION commands instead of\n"
 			 "                               ALTER OWNER commands to set ownership\n"));
-	printf(_("  --with-data                  restore the data\n"));
-	printf(_("  --with-schema                restore the schema\n"));
-	printf(_("  --with-statistics            restore the statistics\n"));
 
 	printf(_("\nConnection options:\n"));
 	printf(_("  -h, --host=HOSTNAME      database server host or socket directory\n"));
@@ -725,8 +565,8 @@ usage(const char *progname)
 	printf(_("  --role=ROLENAME          do SET ROLE before restore\n"));
 
 	printf(_("\n"
-			 "The options -I, -n, -N, -P, -t, -T, --section, and --exclude-database can be\n"
-			 "combined and specified multiple times to select multiple objects.\n"));
+			 "The options -I, -n, -N, -P, -t, -T, and --section can be combined and specified\n"
+			 "multiple times to select multiple objects.\n"));
 	printf(_("\nIf no input file name is supplied, then standard input is used.\n\n"));
 	printf(_("Report bugs to <%s>.\n"), PACKAGE_BUGREPORT);
 	printf(_("%s home page: <%s>\n"), PACKAGE_NAME, PACKAGE_URL);
@@ -831,585 +671,3 @@ read_restore_filters(const char *filename, RestoreOptions *opts)
 
 	filter_free(&fstate);
 }
-
-/*
- * file_exists_in_directory
- *
- * Returns true if the file exists in the given directory.
- */
-static bool
-file_exists_in_directory(const char *dir, const char *filename)
-{
-	struct stat st;
-	char		buf[MAXPGPATH];
-
-	if (snprintf(buf, MAXPGPATH, "%s/%s", dir, filename) >= MAXPGPATH)
-		pg_fatal("directory name too long: \"%s\"", dir);
-
-	return (stat(buf, &st) == 0 && S_ISREG(st.st_mode));
-}
-
-/*
- * read_one_statement
- *
- * This will start reading from passed file pointer using fgetc and read till
- * semicolon(sql statement terminator for global.dat file)
- *
- * EOF is returned if end-of-file input is seen; time to shut down.
- */
-
-static int
-read_one_statement(StringInfo inBuf, FILE *pfile)
-{
-	int			c;				/* character read from getc() */
-	int			m;
-
-	StringInfoData q;
-
-	initStringInfo(&q);
-
-	resetStringInfo(inBuf);
-
-	/*
-	 * Read characters until EOF or the appropriate delimiter is seen.
-	 */
-	while ((c = fgetc(pfile)) != EOF)
-	{
-		if (c != '\'' && c != '"' && c != '\n' && c != ';')
-		{
-			appendStringInfoChar(inBuf, (char) c);
-			while ((c = fgetc(pfile)) != EOF)
-			{
-				if (c != '\'' && c != '"' && c != ';' && c != '\n')
-					appendStringInfoChar(inBuf, (char) c);
-				else
-					break;
-			}
-		}
-
-		if (c == '\'' || c == '"')
-		{
-			appendStringInfoChar(&q, (char) c);
-			m = c;
-
-			while ((c = fgetc(pfile)) != EOF)
-			{
-				appendStringInfoChar(&q, (char) c);
-
-				if (c == m)
-				{
-					appendStringInfoString(inBuf, q.data);
-					resetStringInfo(&q);
-					break;
-				}
-			}
-		}
-
-		if (c == ';')
-		{
-			appendStringInfoChar(inBuf, (char) ';');
-			break;
-		}
-
-		if (c == '\n')
-			appendStringInfoChar(inBuf, (char) '\n');
-	}
-
-	pg_free(q.data);
-
-	/* No input before EOF signal means time to quit. */
-	if (c == EOF && inBuf->len == 0)
-		return EOF;
-
-	/* return something that's not EOF */
-	return 'Q';
-}
-
-/*
- * get_dbnames_list_to_restore
- *
- * This will mark for skipping any entries from dbname_oid_list that pattern match an
- * entry in the db_exclude_patterns list.
- *
- * Returns the number of database to be restored.
- *
- */
-static int
-get_dbnames_list_to_restore(PGconn *conn,
-							SimplePtrList *dbname_oid_list,
-							SimpleStringList db_exclude_patterns)
-{
-	int			count_db = 0;
-	PQExpBuffer query;
-	PGresult   *res;
-
-	query = createPQExpBuffer();
-
-	if (!conn)
-		pg_log_info("considering PATTERN as NAME for --exclude-database option as no database connection while doing pg_restore");
-
-	/*
-	 * Process one by one all dbnames and if specified to skip restoring, then
-	 * remove dbname from list.
-	 */
-	for (SimplePtrListCell *db_cell = dbname_oid_list->head;
-		 db_cell; db_cell = db_cell->next)
-	{
-		DbOidName  *dbidname = (DbOidName *) db_cell->ptr;
-		bool		skip_db_restore = false;
-		PQExpBuffer db_lit = createPQExpBuffer();
-
-		appendStringLiteralConn(db_lit, dbidname->str, conn);
-
-		for (SimpleStringListCell *pat_cell = db_exclude_patterns.head; pat_cell; pat_cell = pat_cell->next)
-		{
-			/*
-			 * If there is an exact match then we don't need to try a pattern
-			 * match
-			 */
-			if (pg_strcasecmp(dbidname->str, pat_cell->val) == 0)
-				skip_db_restore = true;
-			/* Otherwise, try a pattern match if there is a connection */
-			else if (conn)
-			{
-				int			dotcnt;
-
-				appendPQExpBufferStr(query, "SELECT 1 ");
-				processSQLNamePattern(conn, query, pat_cell->val, false,
-									  false, NULL, db_lit->data,
-									  NULL, NULL, NULL, &dotcnt);
-
-				if (dotcnt > 0)
-				{
-					pg_log_error("improper qualified name (too many dotted names): %s",
-								 dbidname->str);
-					PQfinish(conn);
-					exit_nicely(1);
-				}
-
-				res = executeQuery(conn, query->data);
-
-				if ((PQresultStatus(res) == PGRES_TUPLES_OK) && PQntuples(res))
-				{
-					skip_db_restore = true;
-					pg_log_info("database name \"%s\" matches exclude pattern \"%s\"", dbidname->str, pat_cell->val);
-				}
-
-				PQclear(res);
-				resetPQExpBuffer(query);
-			}
-
-			if (skip_db_restore)
-				break;
-		}
-
-		destroyPQExpBuffer(db_lit);
-
-		/*
-		 * Mark db to be skipped or increment the counter of dbs to be
-		 * restored
-		 */
-		if (skip_db_restore)
-		{
-			pg_log_info("excluding database \"%s\"", dbidname->str);
-			dbidname->oid = InvalidOid;
-		}
-		else
-		{
-			count_db++;
-		}
-	}
-
-	destroyPQExpBuffer(query);
-
-	return count_db;
-}
-
-/*
- * get_dbname_oid_list_from_mfile
- *
- * Open map.dat file and read line by line and then prepare a list of database
- * names and corresponding db_oid.
- *
- * Returns, total number of database names in map.dat file.
- */
-static int
-get_dbname_oid_list_from_mfile(const char *dumpdirpath, SimplePtrList *dbname_oid_list)
-{
-	StringInfoData linebuf;
-	FILE	   *pfile;
-	char		map_file_path[MAXPGPATH];
-	int			count = 0;
-
-
-	/*
-	 * If there is only global.dat file in dump, then return from here as
-	 * there is no database to restore.
-	 */
-	if (!file_exists_in_directory(dumpdirpath, "map.dat"))
-	{
-		pg_log_info("database restoring is skipped because file \"%s\" does not exist in directory \"%s\"", "map.dat", dumpdirpath);
-		return 0;
-	}
-
-	snprintf(map_file_path, MAXPGPATH, "%s/map.dat", dumpdirpath);
-
-	/* Open map.dat file. */
-	pfile = fopen(map_file_path, PG_BINARY_R);
-
-	if (pfile == NULL)
-		pg_fatal("could not open file \"%s\": %m", map_file_path);
-
-	initStringInfo(&linebuf);
-
-	/* Append all the dbname/db_oid combinations to the list. */
-	while (pg_get_line_buf(pfile, &linebuf))
-	{
-		Oid			db_oid = InvalidOid;
-		char	   *dbname;
-		DbOidName  *dbidname;
-		int			namelen;
-		char	   *p = linebuf.data;
-
-		/* Extract dboid. */
-		while (isdigit((unsigned char) *p))
-			p++;
-		if (p > linebuf.data && *p == ' ')
-		{
-			sscanf(linebuf.data, "%u", &db_oid);
-			p++;
-		}
-
-		/* dbname is the rest of the line */
-		dbname = p;
-		namelen = strlen(dbname);
-
-		/* Report error and exit if the file has any corrupted data. */
-		if (!OidIsValid(db_oid) || namelen <= 1)
-			pg_fatal("invalid entry in file \"%s\" on line %d", map_file_path,
-					 count + 1);
-
-		pg_log_info("found database \"%s\" (OID: %u) in file \"%s\"",
-					dbname, db_oid, map_file_path);
-
-		dbidname = pg_malloc(offsetof(DbOidName, str) + namelen + 1);
-		dbidname->oid = db_oid;
-		strlcpy(dbidname->str, dbname, namelen);
-
-		simple_ptr_list_append(dbname_oid_list, dbidname);
-		count++;
-	}
-
-	/* Close map.dat file. */
-	fclose(pfile);
-
-	return count;
-}
-
-/*
- * restore_all_databases
- *
- * This will restore databases those dumps are present in
- * directory based on map.dat file mapping.
- *
- * This will skip restoring for databases that are specified with
- * exclude-database option.
- *
- * returns, number of errors while doing restore.
- */
-static int
-restore_all_databases(PGconn *conn, const char *dumpdirpath,
-					  SimpleStringList db_exclude_patterns, RestoreOptions *opts,
-					  int numWorkers)
-{
-	SimplePtrList dbname_oid_list = {NULL, NULL};
-	int			num_db_restore = 0;
-	int			num_total_db;
-	int			n_errors_total;
-	int			count = 0;
-	char	   *connected_db = NULL;
-	bool		dumpData = opts->dumpData;
-	bool		dumpSchema = opts->dumpSchema;
-	bool		dumpStatistics = opts->dumpSchema;
-
-	/* Save db name to reuse it for all the database. */
-	if (opts->cparams.dbname)
-		connected_db = opts->cparams.dbname;
-
-	num_total_db = get_dbname_oid_list_from_mfile(dumpdirpath, &dbname_oid_list);
-
-	/* If map.dat has no entries, return after processing global.dat */
-	if (dbname_oid_list.head == NULL)
-		return process_global_sql_commands(conn, dumpdirpath, opts->filename);
-
-	pg_log_info(ngettext("found %d database name in \"%s\"",
-						 "found %d database names in \"%s\"",
-						 num_total_db),
-				num_total_db, "map.dat");
-
-	if (!conn)
-	{
-		pg_log_info("trying to connect to database \"%s\"", "postgres");
-
-		conn = ConnectDatabase("postgres", NULL, opts->cparams.pghost,
-							   opts->cparams.pgport, opts->cparams.username, TRI_DEFAULT,
-							   false, progname, NULL, NULL, NULL, NULL);
-
-		/* Try with template1. */
-		if (!conn)
-		{
-			pg_log_info("trying to connect to database \"%s\"", "template1");
-
-			conn = ConnectDatabase("template1", NULL, opts->cparams.pghost,
-								   opts->cparams.pgport, opts->cparams.username, TRI_DEFAULT,
-								   false, progname, NULL, NULL, NULL, NULL);
-		}
-	}
-
-	/*
-	 * filter the db list according to the exclude patterns
-	 */
-	num_db_restore = get_dbnames_list_to_restore(conn, &dbname_oid_list,
-												 db_exclude_patterns);
-
-	/* Open global.dat file and execute/append all the global sql commands. */
-	n_errors_total = process_global_sql_commands(conn, dumpdirpath, opts->filename);
-
-	/* Close the db connection as we are done with globals and patterns. */
-	if (conn)
-		PQfinish(conn);
-
-	/* Exit if no db needs to be restored. */
-	if (dbname_oid_list.head == NULL || num_db_restore == 0)
-	{
-		pg_log_info(ngettext("no database needs restoring out of %d database",
-							 "no database needs restoring out of %d databases", num_total_db),
-					num_total_db);
-		return n_errors_total;
-	}
-
-	pg_log_info("need to restore %d databases out of %d databases", num_db_restore, num_total_db);
-
-	/*
-	 * We have a list of databases to restore after processing the
-	 * exclude-database switch(es).  Now we can restore them one by one.
-	 */
-	for (SimplePtrListCell *db_cell = dbname_oid_list.head;
-		 db_cell; db_cell = db_cell->next)
-	{
-		DbOidName  *dbidname = (DbOidName *) db_cell->ptr;
-		char		subdirpath[MAXPGPATH];
-		char		subdirdbpath[MAXPGPATH];
-		char		dbfilename[MAXPGPATH];
-		int			n_errors;
-
-		/* ignore dbs marked for skipping */
-		if (dbidname->oid == InvalidOid)
-			continue;
-
-		/*
-		 * We need to reset override_dbname so that objects can be restored
-		 * into an already created database. (used with -d/--dbname option)
-		 */
-		if (opts->cparams.override_dbname)
-		{
-			pfree(opts->cparams.override_dbname);
-			opts->cparams.override_dbname = NULL;
-		}
-
-		snprintf(subdirdbpath, MAXPGPATH, "%s/databases", dumpdirpath);
-
-		/*
-		 * Look for the database dump file/dir. If there is an {oid}.tar or
-		 * {oid}.dmp file, use it. Otherwise try to use a directory called
-		 * {oid}
-		 */
-		snprintf(dbfilename, MAXPGPATH, "%u.tar", dbidname->oid);
-		if (file_exists_in_directory(subdirdbpath, dbfilename))
-			snprintf(subdirpath, MAXPGPATH, "%s/databases/%u.tar", dumpdirpath, dbidname->oid);
-		else
-		{
-			snprintf(dbfilename, MAXPGPATH, "%u.dmp", dbidname->oid);
-
-			if (file_exists_in_directory(subdirdbpath, dbfilename))
-				snprintf(subdirpath, MAXPGPATH, "%s/databases/%u.dmp", dumpdirpath, dbidname->oid);
-			else
-				snprintf(subdirpath, MAXPGPATH, "%s/databases/%u", dumpdirpath, dbidname->oid);
-		}
-
-		pg_log_info("restoring database \"%s\"", dbidname->str);
-
-		/* If database is already created, then don't set createDB flag. */
-		if (opts->cparams.dbname)
-		{
-			PGconn	   *test_conn;
-
-			test_conn = ConnectDatabase(dbidname->str, NULL, opts->cparams.pghost,
-										opts->cparams.pgport, opts->cparams.username, TRI_DEFAULT,
-										false, progname, NULL, NULL, NULL, NULL);
-			if (test_conn)
-			{
-				PQfinish(test_conn);
-
-				/* Use already created database for connection. */
-				opts->createDB = 0;
-				opts->cparams.dbname = dbidname->str;
-			}
-			else
-			{
-				/* we'll have to create it */
-				opts->createDB = 1;
-				opts->cparams.dbname = connected_db;
-			}
-		}
-
-		/*
-		 * Reset flags - might have been reset in pg_backup_archiver.c by the
-		 * previous restore.
-		 */
-		opts->dumpData = dumpData;
-		opts->dumpSchema = dumpSchema;
-		opts->dumpStatistics = dumpStatistics;
-
-		/* Restore the single database. */
-		n_errors = restore_one_database(subdirpath, opts, numWorkers, true, count);
-
-		/* Print a summary of ignored errors during single database restore. */
-		if (n_errors)
-		{
-			n_errors_total += n_errors;
-			pg_log_warning("errors ignored on database \"%s\" restore: %d", dbidname->str, n_errors);
-		}
-
-		count++;
-	}
-
-	/* Log number of processed databases. */
-	pg_log_info("number of restored databases is %d", num_db_restore);
-
-	/* Free dbname and dboid list. */
-	simple_ptr_list_destroy(&dbname_oid_list);
-
-	return n_errors_total;
-}
-
-/*
- * process_global_sql_commands
- *
- * Open global.dat and execute or copy the sql commands one by one.
- *
- * If outfile is not NULL, copy all sql commands into outfile rather than
- * executing them.
- *
- * Returns the number of errors while processing global.dat
- */
-static int
-process_global_sql_commands(PGconn *conn, const char *dumpdirpath, const char *outfile)
-{
-	char		global_file_path[MAXPGPATH];
-	PGresult   *result;
-	StringInfoData sqlstatement,
-				user_create;
-	FILE	   *pfile;
-	int			n_errors = 0;
-
-	snprintf(global_file_path, MAXPGPATH, "%s/global.dat", dumpdirpath);
-
-	/* Open global.dat file. */
-	pfile = fopen(global_file_path, PG_BINARY_R);
-
-	if (pfile == NULL)
-		pg_fatal("could not open file \"%s\": %m", global_file_path);
-
-	/*
-	 * If outfile is given, then just copy all global.dat file data into
-	 * outfile.
-	 */
-	if (outfile)
-	{
-		copy_or_print_global_file(outfile, pfile);
-		return 0;
-	}
-
-	/* Init sqlstatement to append commands. */
-	initStringInfo(&sqlstatement);
-
-	/* creation statement for our current role */
-	initStringInfo(&user_create);
-	appendStringInfoString(&user_create, "CREATE ROLE ");
-	/* should use fmtId here, but we don't know the encoding */
-	appendStringInfoString(&user_create, PQuser(conn));
-	appendStringInfoChar(&user_create, ';');
-
-	/* Process file till EOF and execute sql statements. */
-	while (read_one_statement(&sqlstatement, pfile) != EOF)
-	{
-		/* don't try to create the role we are connected as */
-		if (strstr(sqlstatement.data, user_create.data))
-			continue;
-
-		pg_log_info("executing query: %s", sqlstatement.data);
-		result = PQexec(conn, sqlstatement.data);
-
-		switch (PQresultStatus(result))
-		{
-			case PGRES_COMMAND_OK:
-			case PGRES_TUPLES_OK:
-			case PGRES_EMPTY_QUERY:
-				break;
-			default:
-				n_errors++;
-				pg_log_error("could not execute query: %s", PQerrorMessage(conn));
-				pg_log_error_detail("Command was: %s", sqlstatement.data);
-		}
-		PQclear(result);
-	}
-
-	/* Print a summary of ignored errors during global.dat. */
-	if (n_errors)
-		pg_log_warning(ngettext("ignored %d error in file \"%s\"",
-								"ignored %d errors in file \"%s\"", n_errors),
-					   n_errors, global_file_path);
-	fclose(pfile);
-
-	return n_errors;
-}
-
-/*
- * copy_or_print_global_file
- *
- * Copy global.dat into the output file.  If "-" is used as outfile,
- * then print commands to stdout.
- */
-static void
-copy_or_print_global_file(const char *outfile, FILE *pfile)
-{
-	char		out_file_path[MAXPGPATH];
-	FILE	   *OPF;
-	int			c;
-
-	/* "-" is used for stdout. */
-	if (strcmp(outfile, "-") == 0)
-		OPF = stdout;
-	else
-	{
-		snprintf(out_file_path, MAXPGPATH, "%s", outfile);
-		OPF = fopen(out_file_path, PG_BINARY_W);
-
-		if (OPF == NULL)
-		{
-			fclose(pfile);
-			pg_fatal("could not open file: \"%s\"", outfile);
-		}
-	}
-
-	/* Append global.dat into output file or print to stdout. */
-	while ((c = fgetc(pfile)) != EOF)
-		fputc(c, OPF);
-
-	fclose(pfile);
-
-	/* Close output file. */
-	if (strcmp(outfile, "-") != 0)
-		fclose(OPF);
-}
diff --git a/src/bin/pg_dump/t/001_basic.pl b/src/bin/pg_dump/t/001_basic.pl
index c3c5fae11eaaf..37d893d5e6a5f 100644
--- a/src/bin/pg_dump/t/001_basic.pl
+++ b/src/bin/pg_dump/t/001_basic.pl
@@ -237,24 +237,6 @@
 	'pg_restore: options -C\/--create and -1\/--single-transaction cannot be used together'
 );
 
-command_fails_like(
-	[ 'pg_restore', '--exclude-database=foo', '--globals-only', '-d', 'xxx' ],
-	qr/\Qpg_restore: error: option --exclude-database cannot be used together with -g\/--globals-only\E/,
-	'pg_restore: option --exclude-database cannot be used together with -g/--globals-only'
-);
-
-command_fails_like(
-	[ 'pg_restore', '--exclude-database=foo', '-d', 'xxx', 'dumpdir' ],
-	qr/\Qpg_restore: error: option --exclude-database can be used only when restoring an archive created by pg_dumpall\E/,
-	'When option --exclude-database is used in pg_restore with dump of pg_dump'
-);
-
-command_fails_like(
-	[ 'pg_restore', '--globals-only', '-d', 'xxx', 'dumpdir' ],
-	qr/\Qpg_restore: error: option -g\/--globals-only can be used only when restoring an archive created by pg_dumpall\E/,
-	'When option --globals-only is not used in pg_restore with dump of pg_dump'
-);
-
 # also fails for -r and -t, but it seems pointless to add more tests for those.
 command_fails_like(
 	[ 'pg_dumpall', '--exclude-database=foo', '--globals-only' ],
@@ -262,8 +244,4 @@
 	'pg_dumpall: option --exclude-database cannot be used together with -g/--globals-only'
 );
 
-command_fails_like(
-	[ 'pg_dumpall', '--format', 'x' ],
-	qr/\Qpg_dumpall: error: unrecognized output format "x";\E/,
-	'pg_dumpall: unrecognized output format');
 done_testing();
diff --git a/src/bin/pg_dump/t/002_pg_dump.pl b/src/bin/pg_dump/t/002_pg_dump.pl
index 2485d8f360e5a..a86b38466de14 100644
--- a/src/bin/pg_dump/t/002_pg_dump.pl
+++ b/src/bin/pg_dump/t/002_pg_dump.pl
@@ -68,7 +68,7 @@
 			'--no-data',
 			'--sequence-data',
 			'--binary-upgrade',
-			'--with-statistics',
+			'--statistics',
 			'--dbname' => 'postgres',    # alternative way to specify database
 		],
 		restore_cmd => [
@@ -76,7 +76,7 @@
 			'--format' => 'custom',
 			'--verbose',
 			'--file' => "$tempdir/binary_upgrade.sql",
-			'--with-statistics',
+			'--statistics',
 			"$tempdir/binary_upgrade.dump",
 		],
 	},
@@ -90,13 +90,13 @@
 			'--format' => 'custom',
 			'--compress' => '1',
 			'--file' => "$tempdir/compression_gzip_custom.dump",
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 		restore_cmd => [
 			'pg_restore',
 			'--file' => "$tempdir/compression_gzip_custom.sql",
-			'--with-statistics',
+			'--statistics',
 			"$tempdir/compression_gzip_custom.dump",
 		],
 		command_like => {
@@ -119,7 +119,7 @@
 			'--format' => 'directory',
 			'--compress' => 'gzip:1',
 			'--file' => "$tempdir/compression_gzip_dir",
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 		# Give coverage for manually compressed blobs.toc files during
@@ -137,7 +137,7 @@
 			'pg_restore',
 			'--jobs' => '2',
 			'--file' => "$tempdir/compression_gzip_dir.sql",
-			'--with-statistics',
+			'--statistics',
 			"$tempdir/compression_gzip_dir",
 		],
 	},
@@ -150,7 +150,7 @@
 			'--format' => 'plain',
 			'--compress' => '1',
 			'--file' => "$tempdir/compression_gzip_plain.sql.gz",
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 		# Decompress the generated file to run through the tests.
@@ -169,13 +169,13 @@
 			'--format' => 'custom',
 			'--compress' => 'lz4',
 			'--file' => "$tempdir/compression_lz4_custom.dump",
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 		restore_cmd => [
 			'pg_restore',
 			'--file' => "$tempdir/compression_lz4_custom.sql",
-			'--with-statistics',
+			'--statistics',
 			"$tempdir/compression_lz4_custom.dump",
 		],
 		command_like => {
@@ -198,7 +198,7 @@
 			'--format' => 'directory',
 			'--compress' => 'lz4:1',
 			'--file' => "$tempdir/compression_lz4_dir",
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 		# Verify that data files were compressed
@@ -210,7 +210,7 @@
 			'pg_restore',
 			'--jobs' => '2',
 			'--file' => "$tempdir/compression_lz4_dir.sql",
-			'--with-statistics',
+			'--statistics',
 			"$tempdir/compression_lz4_dir",
 		],
 	},
@@ -223,7 +223,7 @@
 			'--format' => 'plain',
 			'--compress' => 'lz4',
 			'--file' => "$tempdir/compression_lz4_plain.sql.lz4",
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 		# Decompress the generated file to run through the tests.
@@ -245,13 +245,13 @@
 			'--format' => 'custom',
 			'--compress' => 'zstd',
 			'--file' => "$tempdir/compression_zstd_custom.dump",
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 		restore_cmd => [
 			'pg_restore',
 			'--file' => "$tempdir/compression_zstd_custom.sql",
-			'--with-statistics',
+			'--statistics',
 			"$tempdir/compression_zstd_custom.dump",
 		],
 		command_like => {
@@ -273,7 +273,7 @@
 			'--format' => 'directory',
 			'--compress' => 'zstd:1',
 			'--file' => "$tempdir/compression_zstd_dir",
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 		# Give coverage for manually compressed blobs.toc files during
@@ -294,7 +294,7 @@
 			'pg_restore',
 			'--jobs' => '2',
 			'--file' => "$tempdir/compression_zstd_dir.sql",
-			'--with-statistics',
+			'--statistics',
 			"$tempdir/compression_zstd_dir",
 		],
 	},
@@ -308,7 +308,7 @@
 			'--format' => 'plain',
 			'--compress' => 'zstd:long',
 			'--file' => "$tempdir/compression_zstd_plain.sql.zst",
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 		# Decompress the generated file to run through the tests.
@@ -327,7 +327,7 @@
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/clean.sql",
 			'--clean',
-			'--with-statistics',
+			'--statistics',
 			'--dbname' => 'postgres',    # alternative way to specify database
 		],
 	},
@@ -338,7 +338,7 @@
 			'--clean',
 			'--if-exists',
 			'--encoding' => 'UTF8',      # no-op, just for testing
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -357,7 +357,7 @@
 			'--create',
 			'--no-reconnect',    # no-op, just for testing
 			'--verbose',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -376,7 +376,7 @@
 		dump_cmd => [
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/defaults.sql",
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -385,7 +385,7 @@
 		dump_cmd => [
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/defaults_no_public.sql",
-			'--with-statistics',
+			'--statistics',
 			'regress_pg_dump_test',
 		],
 	},
@@ -395,7 +395,7 @@
 			'pg_dump', '--no-sync',
 			'--clean',
 			'--file' => "$tempdir/defaults_no_public_clean.sql",
-			'--with-statistics',
+			'--statistics',
 			'regress_pg_dump_test',
 		],
 	},
@@ -404,7 +404,7 @@
 		dump_cmd => [
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/defaults_public_owner.sql",
-			'--with-statistics',
+			'--statistics',
 			'regress_public_owner',
 		],
 	},
@@ -419,14 +419,14 @@
 			'pg_dump',
 			'--format' => 'custom',
 			'--file' => "$tempdir/defaults_custom_format.dump",
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 		restore_cmd => [
 			'pg_restore',
 			'--format' => 'custom',
 			'--file' => "$tempdir/defaults_custom_format.sql",
-			'--with-statistics',
+			'--statistics',
 			"$tempdir/defaults_custom_format.dump",
 		],
 		command_like => {
@@ -451,14 +451,14 @@
 			'pg_dump',
 			'--format' => 'directory',
 			'--file' => "$tempdir/defaults_dir_format",
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 		restore_cmd => [
 			'pg_restore',
 			'--format' => 'directory',
 			'--file' => "$tempdir/defaults_dir_format.sql",
-			'--with-statistics',
+			'--statistics',
 			"$tempdir/defaults_dir_format",
 		],
 		command_like => {
@@ -484,13 +484,13 @@
 			'--format' => 'directory',
 			'--jobs' => 2,
 			'--file' => "$tempdir/defaults_parallel",
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 		restore_cmd => [
 			'pg_restore',
 			'--file' => "$tempdir/defaults_parallel.sql",
-			'--with-statistics',
+			'--statistics',
 			"$tempdir/defaults_parallel",
 		],
 	},
@@ -502,14 +502,14 @@
 			'pg_dump',
 			'--format' => 'tar',
 			'--file' => "$tempdir/defaults_tar_format.tar",
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 		restore_cmd => [
 			'pg_restore',
 			'--format' => 'tar',
 			'--file' => "$tempdir/defaults_tar_format.sql",
-			'--with-statistics',
+			'--statistics',
 			"$tempdir/defaults_tar_format.tar",
 		],
 	},
@@ -518,7 +518,7 @@
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/exclude_dump_test_schema.sql",
 			'--exclude-schema' => 'dump_test',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -527,7 +527,7 @@
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/exclude_test_table.sql",
 			'--exclude-table' => 'dump_test.test_table',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -536,7 +536,7 @@
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/exclude_measurement.sql",
 			'--exclude-table-and-children' => 'dump_test.measurement',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -546,7 +546,7 @@
 			'--file' => "$tempdir/exclude_measurement_data.sql",
 			'--exclude-table-data-and-children' => 'dump_test.measurement',
 			'--no-unlogged-table-data',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -556,7 +556,7 @@
 			'--file' => "$tempdir/exclude_test_table_data.sql",
 			'--exclude-table-data' => 'dump_test.test_table',
 			'--no-unlogged-table-data',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -575,7 +575,7 @@
 			'--file' => "$tempdir/pg_dumpall_globals.sql",
 			'--globals-only',
 			'--no-sync',
-			'--with-statistics',
+			'--statistics',
 		],
 	},
 	pg_dumpall_globals_clean => {
@@ -585,14 +585,14 @@
 			'--globals-only',
 			'--clean',
 			'--no-sync',
-			'--with-statistics',
+			'--statistics',
 		],
 	},
 	pg_dumpall_dbprivs => {
 		dump_cmd => [
 			'pg_dumpall', '--no-sync',
 			'--file' => "$tempdir/pg_dumpall_dbprivs.sql",
-			'--with-statistics',
+			'--statistics',
 		],
 	},
 	pg_dumpall_exclude => {
@@ -602,7 +602,7 @@
 			'--file' => "$tempdir/pg_dumpall_exclude.sql",
 			'--exclude-database' => '*dump_test*',
 			'--no-sync',
-			'--with-statistics',
+			'--statistics',
 		],
 	},
 	no_toast_compression => {
@@ -610,7 +610,7 @@
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/no_toast_compression.sql",
 			'--no-toast-compression',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -619,7 +619,7 @@
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/no_large_objects.sql",
 			'--no-large-objects',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -628,7 +628,7 @@
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/no_policies.sql",
 			'--no-policies',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -637,7 +637,7 @@
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/no_privs.sql",
 			'--no-privileges',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -646,7 +646,7 @@
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/no_owner.sql",
 			'--no-owner',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -655,7 +655,7 @@
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/no_table_access_method.sql",
 			'--no-table-access-method',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -664,7 +664,7 @@
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/only_dump_test_schema.sql",
 			'--schema' => 'dump_test',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -675,7 +675,7 @@
 			'--table' => 'dump_test.test_table',
 			'--lock-wait-timeout' =>
 			  (1000 * $PostgreSQL::Test::Utils::timeout_default),
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -686,7 +686,7 @@
 			'--table-and-children' => 'dump_test.measurement',
 			'--lock-wait-timeout' =>
 			  (1000 * $PostgreSQL::Test::Utils::timeout_default),
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -696,7 +696,7 @@
 			'--file' => "$tempdir/role.sql",
 			'--role' => 'regress_dump_test_role',
 			'--schema' => 'dump_test_second_schema',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -709,13 +709,13 @@
 			'--file' => "$tempdir/role_parallel",
 			'--role' => 'regress_dump_test_role',
 			'--schema' => 'dump_test_second_schema',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 		restore_cmd => [
 			'pg_restore',
 			'--file' => "$tempdir/role_parallel.sql",
-			'--with-statistics',
+			'--statistics',
 			"$tempdir/role_parallel",
 		],
 	},
@@ -744,7 +744,7 @@
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/section_pre_data.sql",
 			'--section' => 'pre-data',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -753,7 +753,7 @@
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/section_data.sql",
 			'--section' => 'data',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -762,7 +762,7 @@
 			'pg_dump', '--no-sync',
 			'--file' => "$tempdir/section_post_data.sql",
 			'--section' => 'post-data',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -773,7 +773,7 @@
 			'--schema' => 'dump_test',
 			'--large-objects',
 			'--no-large-objects',
-			'--with-statistics',
+			'--statistics',
 			'postgres',
 		],
 	},
@@ -789,7 +789,7 @@
 			'pg_dump', '--no-sync',
 			"--file=$tempdir/no_data_no_schema.sql", '--no-data',
 			'--no-schema', 'postgres',
-			'--with-statistics',
+			'--statistics',
 		],
 	},
 	statistics_only => {
@@ -799,18 +799,11 @@
 			'postgres',
 		],
 	},
-	schema_only_with_statistics => {
-		dump_cmd => [
-			'pg_dump', '--no-sync',
-			"--file=$tempdir/schema_only_with_statistics.sql",
-			'--schema-only', '--with-statistics', 'postgres',
-		],
-	},
 	no_schema => {
 		dump_cmd => [
 			'pg_dump', '--no-sync',
 			"--file=$tempdir/no_schema.sql", '--no-schema',
-			'--with-statistics', 'postgres',
+			'--statistics', 'postgres',
 		],
 	},);
 
@@ -1087,6 +1080,7 @@
 			test_schema_plus_large_objects => 1,
 		},
 		unlike => {
+			binary_upgrade => 1,
 			no_large_objects => 1,
 			no_owner => 1,
 			schema_only => 1,
@@ -1605,6 +1599,7 @@
 			test_schema_plus_large_objects => 1,
 		},
 		unlike => {
+			binary_upgrade => 1,
 			schema_only => 1,
 			schema_only_with_statistics => 1,
 			no_large_objects => 1,
@@ -2377,17 +2372,19 @@
 		create_sql => 'CREATE DOMAIN dump_test.us_postal_code AS TEXT
 		               COLLATE "C"
 					   DEFAULT \'10014\'
+					   CONSTRAINT nn NOT NULL
 					   CHECK(VALUE ~ \'^\d{5}$\' OR
 							 VALUE ~ \'^\d{5}-\d{4}$\');
+					   COMMENT ON CONSTRAINT nn
+						 ON DOMAIN dump_test.us_postal_code IS \'not null\';
 					   COMMENT ON CONSTRAINT us_postal_code_check
 						 ON DOMAIN dump_test.us_postal_code IS \'check it\';',
 		regexp => qr/^
-			\QCREATE DOMAIN dump_test.us_postal_code AS text COLLATE pg_catalog."C" DEFAULT '10014'::text\E\n\s+
+			\QCREATE DOMAIN dump_test.us_postal_code AS text COLLATE pg_catalog."C" CONSTRAINT nn NOT NULL DEFAULT '10014'::text\E\n\s+
 			\QCONSTRAINT us_postal_code_check CHECK \E
 			\Q(((VALUE ~ '^\d{5}\E
 			\$\Q'::text) OR (VALUE ~ '^\d{5}-\d{4}\E\$
 			\Q'::text)));\E(.|\n)*
-			\QCOMMENT ON CONSTRAINT us_postal_code_check ON DOMAIN dump_test.us_postal_code IS 'check it';\E
 			/xm,
 		like =>
 		  { %full_runs, %dump_test_schema_runs, section_pre_data => 1, },
@@ -2397,6 +2394,30 @@
 		},
 	},
 
+	'COMMENT ON CONSTRAINT ON DOMAIN (1)' => {
+		regexp => qr/^
+		\QCOMMENT ON CONSTRAINT nn ON DOMAIN dump_test.us_postal_code IS 'not null';\E
+		/xm,
+		like =>
+		  { %full_runs, %dump_test_schema_runs, section_pre_data => 1, },
+		unlike => {
+			exclude_dump_test_schema => 1,
+			only_dump_measurement => 1,
+		},
+	},
+
+	'COMMENT ON CONSTRAINT ON DOMAIN (2)' => {
+		regexp => qr/^
+		\QCOMMENT ON CONSTRAINT us_postal_code_check ON DOMAIN dump_test.us_postal_code IS 'check it';\E
+		/xm,
+		like =>
+		  { %full_runs, %dump_test_schema_runs, section_pre_data => 1, },
+		unlike => {
+			exclude_dump_test_schema => 1,
+			only_dump_measurement => 1,
+		},
+	},
+
 	'CREATE FUNCTION dump_test.pltestlang_call_handler' => {
 		create_order => 17,
 		create_sql => 'CREATE FUNCTION dump_test.pltestlang_call_handler()
@@ -4612,9 +4633,9 @@
 			no_schema => 1,
 			section_data => 1,
 			test_schema_plus_large_objects => 1,
-			binary_upgrade => 1,
 		},
 		unlike => {
+			binary_upgrade => 1,
 			no_large_objects => 1,
 			no_privs => 1,
 			schema_only => 1,
@@ -5179,6 +5200,17 @@
 	qr/\Qpg_dump: error: no matching schemas were found for pattern\E/,
 	'no matching schemas');
 
+command_fails_like(
+	[
+		'pg_dump',
+		'--port' => $port,
+		'--strict-names',
+		'--schema-only',
+		'--statistics',
+	],
+	qr/\Qpg_dump: error: options -s\/--schema-only and --statistics cannot be used together\E/,
+	'cannot use --schema-only and --statistics together');
+
 command_fails_like(
 	[
 		'pg_dump',
diff --git a/src/bin/pg_dump/t/006_pg_dumpall.pl b/src/bin/pg_dump/t/006_pg_dumpall.pl
deleted file mode 100644
index c274b777586ad..0000000000000
--- a/src/bin/pg_dump/t/006_pg_dumpall.pl
+++ /dev/null
@@ -1,400 +0,0 @@
-# Copyright (c) 2021-2025, PostgreSQL Global Development Group
-
-use strict;
-use warnings FATAL => 'all';
-
-use PostgreSQL::Test::Cluster;
-use PostgreSQL::Test::Utils;
-use Test::More;
-
-my $tempdir = PostgreSQL::Test::Utils::tempdir;
-my $run_db = 'postgres';
-my $sep = $windows_os ? "\\" : "/";
-
-# Tablespace locations used by "restore_tablespace" test case.
-my $tablespace1 = "${tempdir}${sep}tbl1";
-my $tablespace2 = "${tempdir}${sep}tbl2";
-mkdir($tablespace1) || die "mkdir $tablespace1 $!";
-mkdir($tablespace2) || die "mkdir $tablespace2 $!";
-
-# Scape tablespace locations on Windows.
-$tablespace1 = $windows_os ? ($tablespace1 =~ s/\\/\\\\/gr) : $tablespace1;
-$tablespace2 = $windows_os ? ($tablespace2 =~ s/\\/\\\\/gr) : $tablespace2;
-
-# Where pg_dumpall will be executed.
-my $node = PostgreSQL::Test::Cluster->new('node');
-$node->init;
-$node->start;
-
-
-###############################################################
-# Definition of the pg_dumpall test cases to run.
-#
-# Each of these test cases are named and those names are used for fail
-# reporting and also to save the dump and restore information needed for the
-# test to assert.
-#
-# The "setup_sql" is a psql valid script that contains SQL commands to execute
-# before of actually execute the tests. The setups are all executed before of
-# any test execution.
-#
-# The "dump_cmd" and "restore_cmd" are the commands that will be executed. The
-# "restore_cmd" must have the --file flag to save the restore output so that we
-# can assert on it.
-#
-# The "like" and "unlike" is a regexp that is used to match the pg_restore
-# output. It must have at least one of then filled per test cases but it also
-# can have both. See "excluding_databases" test case for example.
-my %pgdumpall_runs = (
-	restore_roles => {
-		setup_sql => '
-		CREATE ROLE dumpall WITH ENCRYPTED PASSWORD \'admin\' SUPERUSER;
-		CREATE ROLE dumpall2 WITH REPLICATION CONNECTION LIMIT 10;',
-		dump_cmd => [
-			'pg_dumpall',
-			'--format' => 'directory',
-			'--file' => "$tempdir/restore_roles",
-		],
-		restore_cmd => [
-			'pg_restore', '-C',
-			'--format' => 'directory',
-			'--file' => "$tempdir/restore_roles.sql",
-			"$tempdir/restore_roles",
-		],
-		like => qr/
-			^\s*\QCREATE ROLE dumpall;\E\s*\n
-			\s*\QALTER ROLE dumpall WITH SUPERUSER INHERIT NOCREATEROLE NOCREATEDB NOLOGIN NOREPLICATION NOBYPASSRLS PASSWORD 'SCRAM-SHA-256\E
-			[^']+';\s*\n
-			\s*\QCREATE ROLE dumpall2;\E
-			\s*\QALTER ROLE dumpall2 WITH NOSUPERUSER INHERIT NOCREATEROLE NOCREATEDB NOLOGIN REPLICATION NOBYPASSRLS CONNECTION LIMIT 10;\E
-		/xm
-	},
-
-	restore_tablespace => {
-		setup_sql => "
-		CREATE ROLE tap;
-		CREATE TABLESPACE tbl1 OWNER tap LOCATION '$tablespace1';
-		CREATE TABLESPACE tbl2 OWNER tap LOCATION '$tablespace2' WITH (seq_page_cost=1.0);",
-		dump_cmd => [
-			'pg_dumpall',
-			'--format' => 'directory',
-			'--file' => "$tempdir/restore_tablespace",
-		],
-		restore_cmd => [
-			'pg_restore', '-C',
-			'--format' => 'directory',
-			'--file' => "$tempdir/restore_tablespace.sql",
-			"$tempdir/restore_tablespace",
-		],
-		# Match "E" as optional since it is added on LOCATION when running on
-		# Windows.
-		like => qr/^
-			\n\QCREATE TABLESPACE tbl1 OWNER tap LOCATION \E(?:E)?\Q'$tablespace1';\E
-			\n\QCREATE TABLESPACE tbl2 OWNER tap LOCATION \E(?:E)?\Q'$tablespace2';\E
-			\n\QALTER TABLESPACE tbl2 SET (seq_page_cost=1.0);\E
-		/xm,
-	},
-
-	restore_grants => {
-		setup_sql => "
-		CREATE DATABASE tapgrantsdb;
-		CREATE SCHEMA private;
-		CREATE SEQUENCE serial START 101;
-		CREATE FUNCTION fn() RETURNS void AS \$\$
-		BEGIN
-		END;
-		\$\$ LANGUAGE plpgsql;
-		CREATE ROLE super;
-		CREATE ROLE grant1;
-		CREATE ROLE grant2;
-		CREATE ROLE grant3;
-		CREATE ROLE grant4;
-		CREATE ROLE grant5;
-		CREATE ROLE grant6;
-		CREATE ROLE grant7;
-		CREATE ROLE grant8;
-
-		CREATE TABLE t (id int);
-		INSERT INTO t VALUES (1), (2), (3), (4);
-
-		GRANT SELECT ON TABLE t TO grant1;
-		GRANT INSERT ON TABLE t TO grant2;
-		GRANT ALL PRIVILEGES ON TABLE t to grant3;
-		GRANT CONNECT, CREATE ON DATABASE tapgrantsdb TO grant4;
-		GRANT USAGE, CREATE ON SCHEMA private TO grant5;
-		GRANT USAGE, SELECT, UPDATE ON SEQUENCE serial TO grant6;
-		GRANT super TO grant7;
-		GRANT EXECUTE ON FUNCTION fn() TO grant8;
-		",
-		dump_cmd => [
-			'pg_dumpall',
-			'--format' => 'directory',
-			'--file' => "$tempdir/restore_grants",
-		],
-		restore_cmd => [
-			'pg_restore', '-C',
-			'--format' => 'directory',
-			'--file' => "$tempdir/restore_grants.sql",
-			"$tempdir/restore_grants",
-		],
-		like => qr/^
-			\n\QGRANT super TO grant7 WITH INHERIT TRUE GRANTED BY\E
-			(.*\n)*
-			\n\QGRANT ALL ON SCHEMA private TO grant5;\E
-			(.*\n)*
-			\n\QGRANT ALL ON FUNCTION public.fn() TO grant8;\E
-			(.*\n)*
-			\n\QGRANT ALL ON SEQUENCE public.serial TO grant6;\E
-			(.*\n)*
-			\n\QGRANT SELECT ON TABLE public.t TO grant1;\E
-			\n\QGRANT INSERT ON TABLE public.t TO grant2;\E
-			\n\QGRANT ALL ON TABLE public.t TO grant3;\E
-			(.*\n)*
-			\n\QGRANT CREATE,CONNECT ON DATABASE tapgrantsdb TO grant4;\E
-		/xm,
-	},
-
-	excluding_databases => {
-		setup_sql => 'CREATE DATABASE db1;
-		\c db1
-		CREATE TABLE t1 (id int);
-		INSERT INTO t1 VALUES (1), (2), (3), (4);
-		CREATE TABLE t2 (id int);
-		INSERT INTO t2 VALUES (1), (2), (3), (4);
-
-		CREATE DATABASE db2;
-		\c db2
-		CREATE TABLE t3 (id int);
-		INSERT INTO t3 VALUES (1), (2), (3), (4);
-		CREATE TABLE t4 (id int);
-		INSERT INTO t4 VALUES (1), (2), (3), (4);
-
-		CREATE DATABASE dbex3;
-		\c dbex3
-		CREATE TABLE t5 (id int);
-		INSERT INTO t5 VALUES (1), (2), (3), (4);
-		CREATE TABLE t6 (id int);
-		INSERT INTO t6 VALUES (1), (2), (3), (4);
-
-		CREATE DATABASE dbex4;
-		\c dbex4
-		CREATE TABLE t7 (id int);
-		INSERT INTO t7 VALUES (1), (2), (3), (4);
-		CREATE TABLE t8 (id int);
-		INSERT INTO t8 VALUES (1), (2), (3), (4);
-
-		CREATE DATABASE db5;
-		\c db5
-		CREATE TABLE t9 (id int);
-		INSERT INTO t9 VALUES (1), (2), (3), (4);
-		CREATE TABLE t10 (id int);
-		INSERT INTO t10 VALUES (1), (2), (3), (4);
-		',
-		dump_cmd => [
-			'pg_dumpall',
-			'--format' => 'directory',
-			'--file' => "$tempdir/excluding_databases",
-			'--exclude-database' => 'dbex*',
-		],
-		restore_cmd => [
-			'pg_restore', '-C',
-			'--format' => 'directory',
-			'--file' => "$tempdir/excluding_databases.sql",
-			'--exclude-database' => 'db5',
-			"$tempdir/excluding_databases",
-		],
-		like => qr/^
-			\n\QCREATE DATABASE db1\E
-			(.*\n)*
-			\n\QCREATE TABLE public.t1 (\E
-			(.*\n)*
-			\n\QCREATE TABLE public.t2 (\E
-			(.*\n)*
-			\n\QCREATE DATABASE db2\E
-			(.*\n)*
-			\n\QCREATE TABLE public.t3 (\E
-			(.*\n)*
-			\n\QCREATE TABLE public.t4 (/xm,
-		unlike => qr/^
-			\n\QCREATE DATABASE db3\E
-			(.*\n)*
-			\n\QCREATE TABLE public.t5 (\E
-			(.*\n)*
-			\n\QCREATE TABLE public.t6 (\E
-			(.*\n)*
-			\n\QCREATE DATABASE db4\E
-			(.*\n)*
-			\n\QCREATE TABLE public.t7 (\E
-			(.*\n)*
-			\n\QCREATE TABLE public.t8 (\E
-			\n\QCREATE DATABASE db5\E
-			(.*\n)*
-			\n\QCREATE TABLE public.t9 (\E
-			(.*\n)*
-			\n\QCREATE TABLE public.t10 (\E
-		/xm,
-	},
-
-	format_directory => {
-		setup_sql => "CREATE TABLE format_directory(a int, b boolean, c text);
-		INSERT INTO format_directory VALUES (1, true, 'name1'), (2, false, 'name2');",
-		dump_cmd => [
-			'pg_dumpall',
-			'--format' => 'directory',
-			'--file' => "$tempdir/format_directory",
-		],
-		restore_cmd => [
-			'pg_restore', '-C',
-			'--format' => 'directory',
-			'--file' => "$tempdir/format_directory.sql",
-			"$tempdir/format_directory",
-		],
-		like => qr/^\n\QCOPY public.format_directory (a, b, c) FROM stdin;/xm
-	},
-
-	format_tar => {
-		setup_sql => "CREATE TABLE format_tar(a int, b boolean, c text);
-		INSERT INTO format_tar VALUES (1, false, 'name3'), (2, true, 'name4');",
-		dump_cmd => [
-			'pg_dumpall',
-			'--format' => 'tar',
-			'--file' => "$tempdir/format_tar",
-		],
-		restore_cmd => [
-			'pg_restore', '-C',
-			'--format' => 'tar',
-			'--file' => "$tempdir/format_tar.sql",
-			"$tempdir/format_tar",
-		],
-		like => qr/^\n\QCOPY public.format_tar (a, b, c) FROM stdin;/xm
-	},
-
-	format_custom => {
-		setup_sql => "CREATE TABLE format_custom(a int, b boolean, c text);
-		INSERT INTO format_custom VALUES (1, false, 'name5'), (2, true, 'name6');",
-		dump_cmd => [
-			'pg_dumpall',
-			'--format' => 'custom',
-			'--file' => "$tempdir/format_custom",
-		],
-		restore_cmd => [
-			'pg_restore', '-C',
-			'--format' => 'custom',
-			'--file' => "$tempdir/format_custom.sql",
-			"$tempdir/format_custom",
-		],
-		like => qr/^ \n\QCOPY public.format_custom (a, b, c) FROM stdin;/xm
-	},
-
-	dump_globals_only => {
-		setup_sql => "CREATE TABLE format_dir(a int, b boolean, c text);
-		INSERT INTO format_dir VALUES (1, false, 'name5'), (2, true, 'name6');",
-		dump_cmd => [
-			'pg_dumpall',
-			'--format' => 'directory',
-			'--globals-only',
-			'--file' => "$tempdir/dump_globals_only",
-		],
-		restore_cmd => [
-			'pg_restore', '-C', '--globals-only',
-			'--format' => 'directory',
-			'--file' => "$tempdir/dump_globals_only.sql",
-			"$tempdir/dump_globals_only",
-		],
-		like => qr/
-            ^\s*\QCREATE ROLE dumpall;\E\s*\n
-			/xm
-	},);
-
-# First execute the setup_sql
-foreach my $run (sort keys %pgdumpall_runs)
-{
-	if ($pgdumpall_runs{$run}->{setup_sql})
-	{
-		$node->safe_psql($run_db, $pgdumpall_runs{$run}->{setup_sql});
-	}
-}
-
-# Execute the tests
-foreach my $run (sort keys %pgdumpall_runs)
-{
-	# Create a new target cluster to pg_restore each test case run so that we
-	# don't need to take care of the cleanup from the target cluster after each
-	# run.
-	my $target_node = PostgreSQL::Test::Cluster->new("target_$run");
-	$target_node->init;
-	$target_node->start;
-
-	# Dumpall from node cluster.
-	$node->command_ok(\@{ $pgdumpall_runs{$run}->{dump_cmd} },
-		"$run: pg_dumpall runs");
-
-	# Restore the dump on "target_node" cluster.
-	my @restore_cmd = (
-		@{ $pgdumpall_runs{$run}->{restore_cmd} },
-		'--host', $target_node->host, '--port', $target_node->port);
-
-	my ($stdout, $stderr) = run_command(\@restore_cmd);
-
-	# pg_restore --file output file.
-	my $output_file = slurp_file("$tempdir/${run}.sql");
-
-	if (   !($pgdumpall_runs{$run}->{like})
-		&& !($pgdumpall_runs{$run}->{unlike}))
-	{
-		die "missing \"like\" or \"unlike\" in test \"$run\"";
-	}
-
-	if ($pgdumpall_runs{$run}->{like})
-	{
-		like($output_file, $pgdumpall_runs{$run}->{like}, "should dump $run");
-	}
-
-	if ($pgdumpall_runs{$run}->{unlike})
-	{
-		unlike(
-			$output_file,
-			$pgdumpall_runs{$run}->{unlike},
-			"should not dump $run");
-	}
-}
-
-# Some negative test case with dump of pg_dumpall and restore using pg_restore
-# test case 1: when -C is not used in pg_restore with dump of pg_dumpall
-$node->command_fails_like(
-	[
-		'pg_restore',
-		"$tempdir/format_custom",
-		'--format' => 'custom',
-		'--file' => "$tempdir/error_test.sql",
-	],
-	qr/\Qpg_restore: error: option -C\/--create must be specified when restoring an archive created by pg_dumpall\E/,
-	'When -C is not used in pg_restore with dump of pg_dumpall');
-
-# test case 2: When --list option is used with dump of pg_dumpall
-$node->command_fails_like(
-	[
-		'pg_restore',
-		"$tempdir/format_custom", '-C',
-		'--format' => 'custom',
-		'--list',
-		'--file' => "$tempdir/error_test.sql",
-	],
-	qr/\Qpg_restore: error: option -l\/--list cannot be used when restoring an archive created by pg_dumpall\E/,
-	'When --list is used in pg_restore with dump of pg_dumpall');
-
-# test case 3: When non-exist database is given with -d option
-$node->command_fails_like(
-	[
-		'pg_restore',
-		"$tempdir/format_custom", '-C',
-		'--format' => 'custom',
-		'-d' => 'dbpq',
-	],
-	qr/\Qpg_restore: error: could not connect to database "dbpq"\E/,
-	'When non-existent database is given with -d option in pg_restore with dump of pg_dumpall'
-);
-
-$node->stop('fast');
-
-done_testing();
diff --git a/src/bin/pg_rewind/libpq_source.c b/src/bin/pg_rewind/libpq_source.c
index 56c2ad55d4a67..e80edb7077e26 100644
--- a/src/bin/pg_rewind/libpq_source.c
+++ b/src/bin/pg_rewind/libpq_source.c
@@ -215,7 +215,7 @@ libpq_get_current_wal_insert_lsn(rewind_source *source)
 
 	val = run_simple_query(conn, "SELECT pg_current_wal_insert_lsn()");
 
-	if (sscanf(val, "%X/%X", &hi, &lo) != 2)
+	if (sscanf(val, "%X/%08X", &hi, &lo) != 2)
 		pg_fatal("unrecognized result \"%s\" for current WAL insert location", val);
 
 	result = ((uint64) hi) << 32 | lo;
diff --git a/src/bin/pg_rewind/parsexlog.c b/src/bin/pg_rewind/parsexlog.c
index 2cd44625ca368..8f4b282c6b1bb 100644
--- a/src/bin/pg_rewind/parsexlog.c
+++ b/src/bin/pg_rewind/parsexlog.c
@@ -89,11 +89,11 @@ extractPageMap(const char *datadir, XLogRecPtr startpoint, int tliIndex,
 			XLogRecPtr	errptr = xlogreader->EndRecPtr;
 
 			if (errormsg)
-				pg_fatal("could not read WAL record at %X/%X: %s",
+				pg_fatal("could not read WAL record at %X/%08X: %s",
 						 LSN_FORMAT_ARGS(errptr),
 						 errormsg);
 			else
-				pg_fatal("could not read WAL record at %X/%X",
+				pg_fatal("could not read WAL record at %X/%08X",
 						 LSN_FORMAT_ARGS(errptr));
 		}
 
@@ -105,7 +105,7 @@ extractPageMap(const char *datadir, XLogRecPtr startpoint, int tliIndex,
 	 * messed up.
 	 */
 	if (xlogreader->EndRecPtr != endpoint)
-		pg_fatal("end pointer %X/%X is not a valid end point; expected %X/%X",
+		pg_fatal("end pointer %X/%08X is not a valid end point; expected %X/%08X",
 				 LSN_FORMAT_ARGS(endpoint), LSN_FORMAT_ARGS(xlogreader->EndRecPtr));
 
 	XLogReaderFree(xlogreader);
@@ -143,10 +143,10 @@ readOneRecord(const char *datadir, XLogRecPtr ptr, int tliIndex,
 	if (record == NULL)
 	{
 		if (errormsg)
-			pg_fatal("could not read WAL record at %X/%X: %s",
+			pg_fatal("could not read WAL record at %X/%08X: %s",
 					 LSN_FORMAT_ARGS(ptr), errormsg);
 		else
-			pg_fatal("could not read WAL record at %X/%X",
+			pg_fatal("could not read WAL record at %X/%08X",
 					 LSN_FORMAT_ARGS(ptr));
 	}
 	endptr = xlogreader->EndRecPtr;
@@ -211,11 +211,11 @@ findLastCheckpoint(const char *datadir, XLogRecPtr forkptr, int tliIndex,
 		if (record == NULL)
 		{
 			if (errormsg)
-				pg_fatal("could not find previous WAL record at %X/%X: %s",
+				pg_fatal("could not find previous WAL record at %X/%08X: %s",
 						 LSN_FORMAT_ARGS(searchptr),
 						 errormsg);
 			else
-				pg_fatal("could not find previous WAL record at %X/%X",
+				pg_fatal("could not find previous WAL record at %X/%08X",
 						 LSN_FORMAT_ARGS(searchptr));
 		}
 
@@ -458,8 +458,8 @@ extractPageInfo(XLogReaderState *record)
 		 * we don't recognize the type. That's bad - we don't know how to
 		 * track that change.
 		 */
-		pg_fatal("WAL record modifies a relation, but record type is not recognized: "
-				 "lsn: %X/%X, rmid: %d, rmgr: %s, info: %02X",
+		pg_fatal("WAL record modifies a relation, but record type is not recognized:\n"
+				 "lsn: %X/%08X, rmid: %d, rmgr: %s, info: %02X",
 				 LSN_FORMAT_ARGS(record->ReadRecPtr),
 				 rmid, RmgrName(rmid), info);
 	}
diff --git a/src/bin/pg_rewind/pg_rewind.c b/src/bin/pg_rewind/pg_rewind.c
index 9d16c1e6b4757..0c68dd4235e69 100644
--- a/src/bin/pg_rewind/pg_rewind.c
+++ b/src/bin/pg_rewind/pg_rewind.c
@@ -393,7 +393,7 @@ main(int argc, char **argv)
 								   targetHistory, targetNentries,
 								   &divergerec, &lastcommontliIndex);
 
-		pg_log_info("servers diverged at WAL location %X/%X on timeline %u",
+		pg_log_info("servers diverged at WAL location %X/%08X on timeline %u",
 					LSN_FORMAT_ARGS(divergerec),
 					targetHistory[lastcommontliIndex].tli);
 
@@ -461,7 +461,7 @@ main(int argc, char **argv)
 
 	findLastCheckpoint(datadir_target, divergerec, lastcommontliIndex,
 					   &chkptrec, &chkpttli, &chkptredo, restore_command);
-	pg_log_info("rewinding from last common checkpoint at %X/%X on timeline %u",
+	pg_log_info("rewinding from last common checkpoint at %X/%08X on timeline %u",
 				LSN_FORMAT_ARGS(chkptrec), chkpttli);
 
 	/* Initialize the hash table to track the status of each file */
@@ -902,7 +902,7 @@ getTimelineHistory(TimeLineID tli, bool is_source, int *nentries)
 			TimeLineHistoryEntry *entry;
 
 			entry = &history[i];
-			pg_log_debug("%u: %X/%X - %X/%X", entry->tli,
+			pg_log_debug("%u: %X/%08X - %X/%08X", entry->tli,
 						 LSN_FORMAT_ARGS(entry->begin),
 						 LSN_FORMAT_ARGS(entry->end));
 		}
@@ -981,8 +981,8 @@ createBackupLabel(XLogRecPtr startpoint, TimeLineID starttli, XLogRecPtr checkpo
 	strftime(strfbuf, sizeof(strfbuf), "%Y-%m-%d %H:%M:%S %Z", tmp);
 
 	len = snprintf(buf, sizeof(buf),
-				   "START WAL LOCATION: %X/%X (file %s)\n"
-				   "CHECKPOINT LOCATION: %X/%X\n"
+				   "START WAL LOCATION: %X/%08X (file %s)\n"
+				   "CHECKPOINT LOCATION: %X/%08X\n"
 				   "BACKUP METHOD: pg_rewind\n"
 				   "BACKUP FROM: standby\n"
 				   "START TIME: %s\n",
diff --git a/src/bin/pg_rewind/timeline.c b/src/bin/pg_rewind/timeline.c
index 4d9f0d8301bf2..6784969951f57 100644
--- a/src/bin/pg_rewind/timeline.c
+++ b/src/bin/pg_rewind/timeline.c
@@ -66,7 +66,7 @@ rewind_parseTimeLineHistory(char *buffer, TimeLineID targetTLI, int *nentries)
 		if (*ptr == '\0' || *ptr == '#')
 			continue;
 
-		nfields = sscanf(fline, "%u\t%X/%X", &tli, &switchpoint_hi, &switchpoint_lo);
+		nfields = sscanf(fline, "%u\t%X/%08X", &tli, &switchpoint_hi, &switchpoint_lo);
 
 		if (nfields < 1)
 		{
diff --git a/src/bin/pg_test_timing/pg_test_timing.c b/src/bin/pg_test_timing/pg_test_timing.c
index ce7aad4b25a4b..a5621251afcee 100644
--- a/src/bin/pg_test_timing/pg_test_timing.c
+++ b/src/bin/pg_test_timing/pg_test_timing.c
@@ -9,19 +9,30 @@
 #include <limits.h>
 
 #include "getopt_long.h"
+#include "port/pg_bitutils.h"
 #include "portability/instr_time.h"
 
 static const char *progname;
 
 static unsigned int test_duration = 3;
+static double max_rprct = 99.99;
+
+/* record duration in powers of 2 nanoseconds */
+static long long int histogram[32];
+
+/* record counts of first 10K durations directly */
+#define NUM_DIRECT 10000
+static long long int direct_histogram[NUM_DIRECT];
+
+/* separately record highest observed duration */
+static int32 largest_diff;
+static long long int largest_diff_count;
+
 
 static void handle_args(int argc, char *argv[]);
 static uint64 test_timing(unsigned int duration);
 static void output(uint64 loop_count);
 
-/* record duration in powers of 2 microseconds */
-static long long int histogram[32];
-
 int
 main(int argc, char *argv[])
 {
@@ -44,6 +55,7 @@ handle_args(int argc, char *argv[])
 {
 	static struct option long_options[] = {
 		{"duration", required_argument, NULL, 'd'},
+		{"cutoff", required_argument, NULL, 'c'},
 		{NULL, 0, NULL, 0}
 	};
 
@@ -56,7 +68,7 @@ handle_args(int argc, char *argv[])
 	{
 		if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
 		{
-			printf(_("Usage: %s [-d DURATION]\n"), progname);
+			printf(_("Usage: %s [-d DURATION] [-c CUTOFF]\n"), progname);
 			exit(0);
 		}
 		if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0)
@@ -66,7 +78,7 @@ handle_args(int argc, char *argv[])
 		}
 	}
 
-	while ((option = getopt_long(argc, argv, "d:",
+	while ((option = getopt_long(argc, argv, "d:c:",
 								 long_options, &optindex)) != -1)
 	{
 		switch (option)
@@ -93,6 +105,26 @@ handle_args(int argc, char *argv[])
 				}
 				break;
 
+			case 'c':
+				errno = 0;
+				max_rprct = strtod(optarg, &endptr);
+
+				if (endptr == optarg || *endptr != '\0' || errno != 0)
+				{
+					fprintf(stderr, _("%s: invalid argument for option %s\n"),
+							progname, "--cutoff");
+					fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname);
+					exit(1);
+				}
+
+				if (max_rprct < 0 || max_rprct > 100)
+				{
+					fprintf(stderr, _("%s: %s must be in range %u..%u\n"),
+							progname, "--cutoff", 0, 100);
+					exit(1);
+				}
+				break;
+
 			default:
 				fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
 						progname);
@@ -111,7 +143,6 @@ handle_args(int argc, char *argv[])
 		exit(1);
 	}
 
-
 	printf(ngettext("Testing timing overhead for %u second.\n",
 					"Testing timing overhead for %u seconds.\n",
 					test_duration),
@@ -130,23 +161,33 @@ test_timing(unsigned int duration)
 				end_time,
 				temp;
 
-	total_time = duration > 0 ? duration * INT64CONST(1000000) : 0;
+	/*
+	 * Pre-zero the statistics data structures.  They're already zero by
+	 * default, but this helps bring them into processor cache and avoid
+	 * possible timing glitches due to COW behavior.
+	 */
+	memset(direct_histogram, 0, sizeof(direct_histogram));
+	memset(histogram, 0, sizeof(histogram));
+	largest_diff = 0;
+	largest_diff_count = 0;
+
+	total_time = duration > 0 ? duration * INT64CONST(1000000000) : 0;
 
 	INSTR_TIME_SET_CURRENT(start_time);
-	cur = INSTR_TIME_GET_MICROSEC(start_time);
+	cur = INSTR_TIME_GET_NANOSEC(start_time);
 
 	while (time_elapsed < total_time)
 	{
 		int32		diff,
-					bits = 0;
+					bits;
 
 		prev = cur;
 		INSTR_TIME_SET_CURRENT(temp);
-		cur = INSTR_TIME_GET_MICROSEC(temp);
+		cur = INSTR_TIME_GET_NANOSEC(temp);
 		diff = cur - prev;
 
 		/* Did time go backwards? */
-		if (diff < 0)
+		if (unlikely(diff < 0))
 		{
 			fprintf(stderr, _("Detected clock going backwards in time.\n"));
 			fprintf(stderr, _("Time warp: %d ms\n"), diff);
@@ -154,25 +195,37 @@ test_timing(unsigned int duration)
 		}
 
 		/* What is the highest bit in the time diff? */
-		while (diff)
-		{
-			diff >>= 1;
-			bits++;
-		}
+		if (diff > 0)
+			bits = pg_leftmost_one_pos32(diff) + 1;
+		else
+			bits = 0;
 
 		/* Update appropriate duration bucket */
 		histogram[bits]++;
 
+		/* Update direct histogram of time diffs */
+		if (diff < NUM_DIRECT)
+			direct_histogram[diff]++;
+
+		/* Also track the largest observed duration, even if >= NUM_DIRECT */
+		if (diff > largest_diff)
+		{
+			largest_diff = diff;
+			largest_diff_count = 1;
+		}
+		else if (diff == largest_diff)
+			largest_diff_count++;
+
 		loop_count++;
 		INSTR_TIME_SUBTRACT(temp, start_time);
-		time_elapsed = INSTR_TIME_GET_MICROSEC(temp);
+		time_elapsed = INSTR_TIME_GET_NANOSEC(temp);
 	}
 
 	INSTR_TIME_SET_CURRENT(end_time);
 
 	INSTR_TIME_SUBTRACT(end_time, start_time);
 
-	printf(_("Per loop time including overhead: %0.2f ns\n"),
+	printf(_("Average loop time including overhead: %0.2f ns\n"),
 		   INSTR_TIME_GET_DOUBLE(end_time) * 1e9 / loop_count);
 
 	return loop_count;
@@ -181,28 +234,95 @@ test_timing(unsigned int duration)
 static void
 output(uint64 loop_count)
 {
-	int64		max_bit = 31,
-				i;
-	char	   *header1 = _("< us");
-	char	   *header2 = /* xgettext:no-c-format */ _("% of total");
-	char	   *header3 = _("count");
+	int			max_bit = 31;
+	const char *header1 = _("<= ns");
+	const char *header1b = _("ns");
+	const char *header2 = /* xgettext:no-c-format */ _("% of total");
+	const char *header3 = /* xgettext:no-c-format */ _("running %");
+	const char *header4 = _("count");
 	int			len1 = strlen(header1);
 	int			len2 = strlen(header2);
 	int			len3 = strlen(header3);
+	int			len4 = strlen(header4);
+	double		rprct;
+	bool		stopped = false;
 
 	/* find highest bit value */
 	while (max_bit > 0 && histogram[max_bit] == 0)
 		max_bit--;
 
+	/* set minimum column widths */
+	len1 = Max(8, len1);
+	len2 = Max(10, len2);
+	len3 = Max(10, len3);
+	len4 = Max(10, len4);
+
 	printf(_("Histogram of timing durations:\n"));
-	printf("%*s   %*s %*s\n",
-		   Max(6, len1), header1,
-		   Max(10, len2), header2,
-		   Max(10, len3), header3);
-
-	for (i = 0; i <= max_bit; i++)
-		printf("%*ld    %*.5f %*lld\n",
-			   Max(6, len1), 1l << i,
-			   Max(10, len2) - 1, (double) histogram[i] * 100 / loop_count,
-			   Max(10, len3), histogram[i]);
+	printf("%*s   %*s %*s %*s\n",
+		   len1, header1,
+		   len2, header2,
+		   len3, header3,
+		   len4, header4);
+
+	rprct = 0;
+	for (int i = 0; i <= max_bit; i++)
+	{
+		double		prct = (double) histogram[i] * 100 / loop_count;
+
+		rprct += prct;
+		printf("%*ld   %*.4f %*.4f %*lld\n",
+			   len1, (1L << i) - 1,
+			   len2, prct,
+			   len3, rprct,
+			   len4, histogram[i]);
+	}
+
+	printf(_("\nObserved timing durations up to %.4f%%:\n"), max_rprct);
+	printf("%*s   %*s %*s %*s\n",
+		   len1, header1b,
+		   len2, header2,
+		   len3, header3,
+		   len4, header4);
+
+	rprct = 0;
+	for (int i = 0; i < NUM_DIRECT; i++)
+	{
+		if (direct_histogram[i])
+		{
+			double		prct = (double) direct_histogram[i] * 100 / loop_count;
+			bool		print_it = !stopped;
+
+			rprct += prct;
+
+			/* if largest diff is < NUM_DIRECT, be sure we print it */
+			if (i == largest_diff)
+			{
+				if (stopped)
+					printf("...\n");
+				print_it = true;
+			}
+
+			if (print_it)
+				printf("%*d   %*.4f %*.4f %*lld\n",
+					   len1, i,
+					   len2, prct,
+					   len3, rprct,
+					   len4, direct_histogram[i]);
+			if (rprct >= max_rprct)
+				stopped = true;
+		}
+	}
+
+	/* print largest diff when it's outside the array range */
+	if (largest_diff >= NUM_DIRECT)
+	{
+		double		prct = (double) largest_diff_count * 100 / loop_count;
+
+		printf("...\n");
+		printf("%*d   %*.4f %*.4f %*lld\n",
+			   len1, largest_diff,
+			   len2, prct,
+			   len3, 100.0,
+			   len4, largest_diff_count);
+	}
 }
diff --git a/src/bin/pg_test_timing/t/001_basic.pl b/src/bin/pg_test_timing/t/001_basic.pl
index 6554cd981af8f..9912acc052a29 100644
--- a/src/bin/pg_test_timing/t/001_basic.pl
+++ b/src/bin/pg_test_timing/t/001_basic.pl
@@ -25,5 +25,22 @@
 	[ 'pg_test_timing', '--duration' => '0' ],
 	qr/\Qpg_test_timing: --duration must be in range 1..4294967295\E/,
 	'pg_test_timing: --duration must be in range');
+command_fails_like(
+	[ 'pg_test_timing', '--cutoff' => '101' ],
+	qr/\Qpg_test_timing: --cutoff must be in range 0..100\E/,
+	'pg_test_timing: --cutoff must be in range');
+
+#########################################
+# We obviously can't check for specific output, but we can
+# do a simple run and make sure it produces something.
+
+command_like(
+	[ 'pg_test_timing', '--duration' => '1' ],
+	qr/
+\QTesting timing overhead for 1 second.\E.*
+\QHistogram of timing durations:\E.*
+\QObserved timing durations up to 99.9900%:\E
+/sx,
+	'pg_test_timing: sanity check');
 
 done_testing();
diff --git a/src/bin/pg_upgrade/check.c b/src/bin/pg_upgrade/check.c
index 81865cd3e4859..310f53c55771b 100644
--- a/src/bin/pg_upgrade/check.c
+++ b/src/bin/pg_upgrade/check.c
@@ -23,11 +23,12 @@ static void check_for_isn_and_int8_passing_mismatch(ClusterInfo *cluster);
 static void check_for_user_defined_postfix_ops(ClusterInfo *cluster);
 static void check_for_incompatible_polymorphics(ClusterInfo *cluster);
 static void check_for_tables_with_oids(ClusterInfo *cluster);
+static void check_for_not_null_inheritance(ClusterInfo *cluster);
 static void check_for_pg_role_prefix(ClusterInfo *cluster);
 static void check_for_new_tablespace_dir(void);
 static void check_for_user_defined_encoding_conversions(ClusterInfo *cluster);
 static void check_for_unicode_update(ClusterInfo *cluster);
-static void check_new_cluster_logical_replication_slots(void);
+static void check_new_cluster_replication_slots(void);
 static void check_new_cluster_subscription_configuration(void);
 static void check_old_cluster_for_valid_slots(void);
 static void check_old_cluster_subscription_state(void);
@@ -168,6 +169,7 @@ static DataTypesUsageChecks data_types_usage_checks[] =
 		/* pg_class.oid is preserved, so 'regclass' is OK */
 		"           'regcollation', "
 		"           'regconfig', "
+		/* pg_database.oid is preserved, so 'regdatabase' is OK */
 		"           'regdictionary', "
 		"           'regnamespace', "
 		"           'regoper', "
@@ -419,7 +421,7 @@ process_data_type_check(DbInfo *dbinfo, PGresult *res, void *arg)
 	if (!state->result)
 	{
 		pg_log(PG_REPORT, "failed check: %s", _(state->check->status));
-		appendPQExpBuffer(*state->report, "\n%s\n%s    %s\n",
+		appendPQExpBuffer(*state->report, "\n%s\n%s\n    %s\n",
 						  _(state->check->report_text),
 						  _("A list of the problem columns is in the file:"),
 						  output_path);
@@ -629,7 +631,7 @@ check_and_dump_old_cluster(void)
 		 * Before that the logical slots are not upgraded, so we will not be
 		 * able to upgrade the logical replication clusters completely.
 		 */
-		get_subscription_count(&old_cluster);
+		get_subscription_info(&old_cluster);
 		check_old_cluster_subscription_state();
 	}
 
@@ -671,6 +673,14 @@ check_and_dump_old_cluster(void)
 	if (GET_MAJOR_VERSION(old_cluster.major_version) <= 1100)
 		check_for_tables_with_oids(&old_cluster);
 
+	/*
+	 * Pre-PG 18 allowed child tables to omit not-null constraints that their
+	 * parents columns have, but schema restore fails for them.  Verify there
+	 * are none, iff applicable.
+	 */
+	if (GET_MAJOR_VERSION(old_cluster.major_version) <= 1800)
+		check_for_not_null_inheritance(&old_cluster);
+
 	/*
 	 * Pre-PG 10 allowed tables with 'unknown' type columns and non WAL logged
 	 * hash indexes
@@ -754,7 +764,7 @@ check_new_cluster(void)
 
 	check_for_new_tablespace_dir();
 
-	check_new_cluster_logical_replication_slots();
+	check_new_cluster_replication_slots();
 
 	check_new_cluster_subscription_configuration();
 }
@@ -946,12 +956,12 @@ check_for_new_tablespace_dir(void)
 
 	prep_status("Checking for new cluster tablespace directories");
 
-	for (tblnum = 0; tblnum < os_info.num_old_tablespaces; tblnum++)
+	for (tblnum = 0; tblnum < new_cluster.num_tablespaces; tblnum++)
 	{
 		struct stat statbuf;
 
 		snprintf(new_tablespace_dir, MAXPGPATH, "%s%s",
-				 os_info.old_tablespaces[tblnum],
+				 new_cluster.tablespaces[tblnum],
 				 new_cluster.tablespace_suffix);
 
 		if (stat(new_tablespace_dir, &statbuf) == 0 || errno != ENOENT)
@@ -1003,17 +1013,17 @@ create_script_for_old_cluster_deletion(char **deletion_script_file_name)
 	 * directory.  We can't create a proper old cluster delete script in that
 	 * case.
 	 */
-	for (tblnum = 0; tblnum < os_info.num_old_tablespaces; tblnum++)
+	for (tblnum = 0; tblnum < new_cluster.num_tablespaces; tblnum++)
 	{
-		char		old_tablespace_dir[MAXPGPATH];
+		char		new_tablespace_dir[MAXPGPATH];
 
-		strlcpy(old_tablespace_dir, os_info.old_tablespaces[tblnum], MAXPGPATH);
-		canonicalize_path(old_tablespace_dir);
-		if (path_is_prefix_of_path(old_cluster_pgdata, old_tablespace_dir))
+		strlcpy(new_tablespace_dir, new_cluster.tablespaces[tblnum], MAXPGPATH);
+		canonicalize_path(new_tablespace_dir);
+		if (path_is_prefix_of_path(old_cluster_pgdata, new_tablespace_dir))
 		{
 			/* reproduce warning from CREATE TABLESPACE that is in the log */
 			pg_log(PG_WARNING,
-				   "\nWARNING:  user-defined tablespace locations should not be inside the data directory, i.e. %s", old_tablespace_dir);
+				   "\nWARNING:  user-defined tablespace locations should not be inside the data directory, i.e. %s", new_tablespace_dir);
 
 			/* Unlink file in case it is left over from a previous run. */
 			unlink(*deletion_script_file_name);
@@ -1041,9 +1051,9 @@ create_script_for_old_cluster_deletion(char **deletion_script_file_name)
 	/* delete old cluster's alternate tablespaces */
 	old_tblspc_suffix = pg_strdup(old_cluster.tablespace_suffix);
 	fix_path_separator(old_tblspc_suffix);
-	for (tblnum = 0; tblnum < os_info.num_old_tablespaces; tblnum++)
+	for (tblnum = 0; tblnum < old_cluster.num_tablespaces; tblnum++)
 		fprintf(script, RMDIR_CMD " %c%s%s%c\n", PATH_QUOTE,
-				fix_path_separator(os_info.old_tablespaces[tblnum]),
+				fix_path_separator(old_cluster.tablespaces[tblnum]),
 				old_tblspc_suffix, PATH_QUOTE);
 	pfree(old_tblspc_suffix);
 
@@ -1623,6 +1633,93 @@ check_for_tables_with_oids(ClusterInfo *cluster)
 		check_ok();
 }
 
+/*
+ * Callback function for processing results of query for
+ * check_for_not_null_inheritance.
+ */
+static void
+process_inconsistent_notnull(DbInfo *dbinfo, PGresult *res, void *arg)
+{
+	UpgradeTaskReport *report = (UpgradeTaskReport *) arg;
+	int			ntups = PQntuples(res);
+	int			i_nspname = PQfnumber(res, "nspname");
+	int			i_relname = PQfnumber(res, "relname");
+	int			i_attname = PQfnumber(res, "attname");
+
+	AssertVariableIsOfType(&process_inconsistent_notnull,
+						   UpgradeTaskProcessCB);
+
+	if (ntups == 0)
+		return;
+
+	if (report->file == NULL &&
+		(report->file = fopen_priv(report->path, "w")) == NULL)
+		pg_fatal("could not open file \"%s\": %m", report->path);
+
+	fprintf(report->file, "In database: %s\n", dbinfo->db_name);
+
+	for (int rowno = 0; rowno < ntups; rowno++)
+	{
+		fprintf(report->file, "  %s.%s.%s\n",
+				PQgetvalue(res, rowno, i_nspname),
+				PQgetvalue(res, rowno, i_relname),
+				PQgetvalue(res, rowno, i_attname));
+	}
+}
+
+/*
+ * check_for_not_null_inheritance()
+ *
+ * An attempt to create child tables lacking not-null constraints that are
+ * present in their parents errors out.  This can no longer occur since 18,
+ * but previously there were various ways for that to happen.  Check that
+ * the cluster to be upgraded doesn't have any of those problems.
+ */
+static void
+check_for_not_null_inheritance(ClusterInfo *cluster)
+{
+	UpgradeTaskReport report;
+	UpgradeTask *task;
+	const char *query;
+
+	prep_status("Checking for not-null constraint inconsistencies");
+
+	report.file = NULL;
+	snprintf(report.path, sizeof(report.path), "%s/%s",
+			 log_opts.basedir,
+			 "not_null_inconsistent_columns.txt");
+
+	query = "SELECT nspname, cc.relname, ac.attname "
+		"FROM pg_catalog.pg_inherits i, pg_catalog.pg_attribute ac, "
+		"     pg_catalog.pg_attribute ap, pg_catalog.pg_class cc, "
+		"     pg_catalog.pg_namespace nc "
+		"WHERE cc.oid = ac.attrelid AND i.inhrelid = ac.attrelid "
+		"      AND i.inhparent = ap.attrelid AND ac.attname = ap.attname "
+		"      AND cc.relnamespace = nc.oid "
+		"      AND ap.attnum > 0 and ap.attnotnull AND NOT ac.attnotnull";
+
+	task = upgrade_task_create();
+	upgrade_task_add_step(task, query,
+						  process_inconsistent_notnull,
+						  true, &report);
+	upgrade_task_run(task, cluster);
+	upgrade_task_free(task);
+
+	if (report.file)
+	{
+		fclose(report.file);
+		pg_log(PG_REPORT, "fatal");
+		pg_fatal("Your installation contains inconsistent NOT NULL constraints.\n"
+				 "If the parent column(s) are NOT NULL, then the child column must\n"
+				 "also be marked NOT NULL, or the upgrade will fail.\n"
+				 "You can fix this by running\n"
+				 "  ALTER TABLE tablename ALTER column SET NOT NULL;\n"
+				 "on each column listed in the file:\n"
+				 "    %s", report.path);
+	}
+	else
+		check_ok();
+}
 
 /*
  * check_for_pg_role_prefix()
@@ -1943,48 +2040,80 @@ check_for_unicode_update(ClusterInfo *cluster)
 }
 
 /*
- * check_new_cluster_logical_replication_slots()
+ * check_new_cluster_replication_slots()
  *
- * Verify that there are no logical replication slots on the new cluster and
- * that the parameter settings necessary for creating slots are sufficient.
+ * Validate the new cluster's readiness for migrating replication slots:
+ * - Ensures no existing logical replication slots on the new cluster when
+ *   migrating logical slots.
+ * - Ensure conflict detection slot does not exist on the new cluster when
+ *   migrating subscriptions with retain_dead_tuples enabled.
+ * - Ensure that the parameter settings on the new cluster necessary for
+ *   creating slots are sufficient.
  */
 static void
-check_new_cluster_logical_replication_slots(void)
+check_new_cluster_replication_slots(void)
 {
 	PGresult   *res;
 	PGconn	   *conn;
 	int			nslots_on_old;
 	int			nslots_on_new;
+	int			rdt_slot_on_new;
 	int			max_replication_slots;
 	char	   *wal_level;
+	int			i_nslots_on_new;
+	int			i_rdt_slot_on_new;
 
-	/* Logical slots can be migrated since PG17. */
+	/*
+	 * Logical slots can be migrated since PG17 and a physical slot
+	 * CONFLICT_DETECTION_SLOT can be migrated since PG19.
+	 */
 	if (GET_MAJOR_VERSION(old_cluster.major_version) <= 1600)
 		return;
 
 	nslots_on_old = count_old_cluster_logical_slots();
 
-	/* Quick return if there are no logical slots to be migrated. */
-	if (nslots_on_old == 0)
+	/*
+	 * Quick return if there are no slots to be migrated and no subscriptions
+	 * have the retain_dead_tuples option enabled.
+	 */
+	if (nslots_on_old == 0 && !old_cluster.sub_retain_dead_tuples)
 		return;
 
 	conn = connectToServer(&new_cluster, "template1");
 
-	prep_status("Checking for new cluster logical replication slots");
+	prep_status("Checking for new cluster replication slots");
 
-	res = executeQueryOrDie(conn, "SELECT count(*) "
-							"FROM pg_catalog.pg_replication_slots "
-							"WHERE slot_type = 'logical' AND "
-							"temporary IS FALSE;");
+	res = executeQueryOrDie(conn, "SELECT %s AS nslots_on_new, %s AS rdt_slot_on_new "
+							"FROM pg_catalog.pg_replication_slots",
+							nslots_on_old > 0
+							? "COUNT(*) FILTER (WHERE slot_type = 'logical' AND temporary IS FALSE)"
+							: "0",
+							old_cluster.sub_retain_dead_tuples
+							? "COUNT(*) FILTER (WHERE slot_name = 'pg_conflict_detection')"
+							: "0");
 
 	if (PQntuples(res) != 1)
-		pg_fatal("could not count the number of logical replication slots");
+		pg_fatal("could not count the number of replication slots");
 
-	nslots_on_new = atoi(PQgetvalue(res, 0, 0));
+	i_nslots_on_new = PQfnumber(res, "nslots_on_new");
+	i_rdt_slot_on_new = PQfnumber(res, "rdt_slot_on_new");
+
+	nslots_on_new = atoi(PQgetvalue(res, 0, i_nslots_on_new));
 
 	if (nslots_on_new)
+	{
+		Assert(nslots_on_old);
 		pg_fatal("expected 0 logical replication slots but found %d",
 				 nslots_on_new);
+	}
+
+	rdt_slot_on_new = atoi(PQgetvalue(res, 0, i_rdt_slot_on_new));
+
+	if (rdt_slot_on_new)
+	{
+		Assert(old_cluster.sub_retain_dead_tuples);
+		pg_fatal("The replication slot \"pg_conflict_detection\" already exists on the new cluster");
+	}
 
 	PQclear(res);
 
@@ -1997,12 +2126,24 @@ check_new_cluster_logical_replication_slots(void)
 
 	wal_level = PQgetvalue(res, 0, 0);
 
-	if (strcmp(wal_level, "logical") != 0)
+	if (nslots_on_old > 0 && strcmp(wal_level, "logical") != 0)
 		pg_fatal("\"wal_level\" must be \"logical\" but is set to \"%s\"",
 				 wal_level);
 
+	if (old_cluster.sub_retain_dead_tuples &&
+		strcmp(wal_level, "minimal") == 0)
+		pg_fatal("\"wal_level\" must be \"replica\" or \"logical\" but is set to \"%s\"",
+				 wal_level);
+
 	max_replication_slots = atoi(PQgetvalue(res, 1, 0));
 
+	if (old_cluster.sub_retain_dead_tuples &&
+		nslots_on_old + 1 > max_replication_slots)
+		pg_fatal("\"max_replication_slots\" (%d) must be greater than or equal to the number of "
+				 "logical replication slots on the old cluster plus one additional slot required "
+				 "for retaining conflict detection information (%d)",
+				 max_replication_slots, nslots_on_old + 1);
+
 	if (nslots_on_old > max_replication_slots)
 		pg_fatal("\"max_replication_slots\" (%d) must be greater than or equal to the number of "
 				 "logical replication slots (%d) on the old cluster",
@@ -2114,6 +2255,22 @@ check_old_cluster_for_valid_slots(void)
 						"The slot \"%s\" has not consumed the WAL yet\n",
 						slot->slotname);
 			}
+
+			/*
+			 * The name "pg_conflict_detection" (defined as
+			 * CONFLICT_DETECTION_SLOT) has been reserved for logical
+			 * replication conflict detection slot since PG19.
+			 */
+			if (strcmp(slot->slotname, "pg_conflict_detection") == 0)
+			{
+				if (script == NULL &&
+					(script = fopen_priv(output_path, "w")) == NULL)
+					pg_fatal("could not open file \"%s\": %m", output_path);
+
+				fprintf(script,
+						"The slot name \"%s\" is reserved\n",
+						slot->slotname);
+			}
 		}
 	}
 
diff --git a/src/bin/pg_upgrade/dump.c b/src/bin/pg_upgrade/dump.c
index 183f08ce1e86f..55f6e7b4d9c3e 100644
--- a/src/bin/pg_upgrade/dump.c
+++ b/src/bin/pg_upgrade/dump.c
@@ -58,7 +58,7 @@ generate_old_dump(void)
 						   (user_opts.transfer_mode == TRANSFER_MODE_SWAP) ?
 						   "" : "--sequence-data",
 						   log_opts.verbose ? "--verbose" : "",
-						   user_opts.do_statistics ? "--with-statistics" : "--no-statistics",
+						   user_opts.do_statistics ? "--statistics" : "--no-statistics",
 						   log_opts.dumpdir,
 						   sql_file_name, escaped_connstr.data);
 
diff --git a/src/bin/pg_upgrade/info.c b/src/bin/pg_upgrade/info.c
index 4b7a56f5b3be4..c39eb077c2fae 100644
--- a/src/bin/pg_upgrade/info.c
+++ b/src/bin/pg_upgrade/info.c
@@ -443,10 +443,26 @@ get_db_infos(ClusterInfo *cluster)
 
 	for (tupnum = 0; tupnum < ntups; tupnum++)
 	{
+		char	   *spcloc = PQgetvalue(res, tupnum, i_spclocation);
+		bool		inplace = spcloc[0] && !is_absolute_path(spcloc);
+
 		dbinfos[tupnum].db_oid = atooid(PQgetvalue(res, tupnum, i_oid));
 		dbinfos[tupnum].db_name = pg_strdup(PQgetvalue(res, tupnum, i_datname));
-		snprintf(dbinfos[tupnum].db_tablespace, sizeof(dbinfos[tupnum].db_tablespace), "%s",
-				 PQgetvalue(res, tupnum, i_spclocation));
+
+		/*
+		 * The tablespace location might be "", meaning the cluster default
+		 * location, i.e. pg_default or pg_global.  For in-place tablespaces,
+		 * pg_tablespace_location() returns a path relative to the data
+		 * directory.
+		 */
+		if (inplace)
+			snprintf(dbinfos[tupnum].db_tablespace,
+					 sizeof(dbinfos[tupnum].db_tablespace),
+					 "%s/%s", cluster->pgdata, spcloc);
+		else
+			snprintf(dbinfos[tupnum].db_tablespace,
+					 sizeof(dbinfos[tupnum].db_tablespace),
+					 "%s", spcloc);
 	}
 	PQclear(res);
 
@@ -616,11 +632,21 @@ process_rel_infos(DbInfo *dbinfo, PGresult *res, void *arg)
 		/* Is the tablespace oid non-default? */
 		if (atooid(PQgetvalue(res, relnum, i_reltablespace)) != 0)
 		{
+			char	   *spcloc = PQgetvalue(res, relnum, i_spclocation);
+			bool		inplace = spcloc[0] && !is_absolute_path(spcloc);
+
 			/*
 			 * The tablespace location might be "", meaning the cluster
-			 * default location, i.e. pg_default or pg_global.
+			 * default location, i.e. pg_default or pg_global.  For in-place
+			 * tablespaces, pg_tablespace_location() returns a path relative
+			 * to the data directory.
 			 */
-			tablespace = PQgetvalue(res, relnum, i_spclocation);
+			if (inplace)
+				tablespace = psprintf("%s/%s",
+									  os_info.running_cluster->pgdata,
+									  spcloc);
+			else
+				tablespace = spcloc;
 
 			/* Can we reuse the previous string allocation? */
 			if (last_tablespace && strcmp(tablespace, last_tablespace) == 0)
@@ -630,6 +656,10 @@ process_rel_infos(DbInfo *dbinfo, PGresult *res, void *arg)
 				last_tablespace = curr->tablespace = pg_strdup(tablespace);
 				curr->tblsp_alloc = true;
 			}
+
+			/* Free palloc'd string for in-place tablespaces. */
+			if (inplace)
+				pfree(tablespace);
 		}
 		else
 			/* A zero reltablespace oid indicates the database tablespace. */
@@ -752,20 +782,33 @@ count_old_cluster_logical_slots(void)
 }
 
 /*
- * get_subscription_count()
+ * get_subscription_info()
  *
- * Gets the number of subscriptions in the cluster.
+ * Gets the information of subscriptions in the cluster.
  */
 void
-get_subscription_count(ClusterInfo *cluster)
+get_subscription_info(ClusterInfo *cluster)
 {
 	PGconn	   *conn;
 	PGresult   *res;
+	int			i_nsub;
+	int			i_retain_dead_tuples;
 
 	conn = connectToServer(cluster, "template1");
-	res = executeQueryOrDie(conn, "SELECT count(*) "
-							"FROM pg_catalog.pg_subscription");
-	cluster->nsubs = atoi(PQgetvalue(res, 0, 0));
+	if (GET_MAJOR_VERSION(cluster->major_version) >= 1900)
+		res = executeQueryOrDie(conn, "SELECT count(*) AS nsub,"
+								"COUNT(CASE WHEN subretaindeadtuples THEN 1 END) > 0 AS retain_dead_tuples "
+								"FROM pg_catalog.pg_subscription");
+	else
+		res = executeQueryOrDie(conn, "SELECT count(*) AS nsub,"
+								"'f' AS retain_dead_tuples "
+								"FROM pg_catalog.pg_subscription");
+
+	i_nsub = PQfnumber(res, "nsub");
+	i_retain_dead_tuples = PQfnumber(res, "retain_dead_tuples");
+
+	cluster->nsubs = atoi(PQgetvalue(res, 0, i_nsub));
+	cluster->sub_retain_dead_tuples = (strcmp(PQgetvalue(res, 0, i_retain_dead_tuples), "t") == 0);
 
 	PQclear(res);
 	PQfinish(conn);
diff --git a/src/bin/pg_upgrade/parallel.c b/src/bin/pg_upgrade/parallel.c
index 056aa2edaee3f..6d7941844a7c8 100644
--- a/src/bin/pg_upgrade/parallel.c
+++ b/src/bin/pg_upgrade/parallel.c
@@ -40,6 +40,7 @@ typedef struct
 	char	   *old_pgdata;
 	char	   *new_pgdata;
 	char	   *old_tablespace;
+	char	   *new_tablespace;
 } transfer_thread_arg;
 
 static exec_thread_arg **exec_thread_args;
@@ -171,7 +172,7 @@ win32_exec_prog(exec_thread_arg *args)
 void
 parallel_transfer_all_new_dbs(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
 							  char *old_pgdata, char *new_pgdata,
-							  char *old_tablespace)
+							  char *old_tablespace, char *new_tablespace)
 {
 #ifndef WIN32
 	pid_t		child;
@@ -181,7 +182,7 @@ parallel_transfer_all_new_dbs(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
 #endif
 
 	if (user_opts.jobs <= 1)
-		transfer_all_new_dbs(old_db_arr, new_db_arr, old_pgdata, new_pgdata, NULL);
+		transfer_all_new_dbs(old_db_arr, new_db_arr, old_pgdata, new_pgdata, NULL, NULL);
 	else
 	{
 		/* parallel */
@@ -225,7 +226,7 @@ parallel_transfer_all_new_dbs(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
 		if (child == 0)
 		{
 			transfer_all_new_dbs(old_db_arr, new_db_arr, old_pgdata, new_pgdata,
-								 old_tablespace);
+								 old_tablespace, new_tablespace);
 			/* if we take another exit path, it will be non-zero */
 			/* use _exit to skip atexit() functions */
 			_exit(0);
@@ -246,6 +247,7 @@ parallel_transfer_all_new_dbs(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
 		new_arg->new_pgdata = pg_strdup(new_pgdata);
 		pg_free(new_arg->old_tablespace);
 		new_arg->old_tablespace = old_tablespace ? pg_strdup(old_tablespace) : NULL;
+		new_arg->new_tablespace = new_tablespace ? pg_strdup(new_tablespace) : NULL;
 
 		child = (HANDLE) _beginthreadex(NULL, 0, (void *) win32_transfer_all_new_dbs,
 										new_arg, 0, NULL);
@@ -263,7 +265,8 @@ DWORD
 win32_transfer_all_new_dbs(transfer_thread_arg *args)
 {
 	transfer_all_new_dbs(args->old_db_arr, args->new_db_arr, args->old_pgdata,
-						 args->new_pgdata, args->old_tablespace);
+						 args->new_pgdata, args->old_tablespace,
+						 args->new_tablespace);
 
 	/* terminates thread */
 	return 0;
diff --git a/src/bin/pg_upgrade/pg_upgrade.c b/src/bin/pg_upgrade/pg_upgrade.c
index 536e49d26168b..d5cd5bf0b3a6b 100644
--- a/src/bin/pg_upgrade/pg_upgrade.c
+++ b/src/bin/pg_upgrade/pg_upgrade.c
@@ -67,6 +67,7 @@ static void set_frozenxids(bool minmxid_only);
 static void make_outputdirs(char *pgdata);
 static void setup(char *argv0);
 static void create_logical_replication_slots(void);
+static void create_conflict_detection_slot(void);
 
 ClusterInfo old_cluster,
 			new_cluster;
@@ -88,6 +89,7 @@ int
 main(int argc, char **argv)
 {
 	char	   *deletion_script_file_name = NULL;
+	bool		migrate_logical_slots;
 
 	/*
 	 * pg_upgrade doesn't currently use common/logging.c, but initialize it
@@ -198,18 +200,39 @@ main(int argc, char **argv)
 			  new_cluster.pgdata);
 	check_ok();
 
+	migrate_logical_slots = count_old_cluster_logical_slots();
+
 	/*
-	 * Migrate the logical slots to the new cluster.  Note that we need to do
-	 * this after resetting WAL because otherwise the required WAL would be
-	 * removed and slots would become unusable.  There is a possibility that
-	 * background processes might generate some WAL before we could create the
-	 * slots in the new cluster but we can ignore that WAL as that won't be
-	 * required downstream.
+	 * Migrate replication slots to the new cluster.
+	 *
+	 * Note that we must migrate logical slots after resetting WAL because
+	 * otherwise the required WAL would be removed and slots would become
+	 * unusable.  There is a possibility that background processes might
+	 * generate some WAL before we could create the slots in the new cluster
+	 * but we can ignore that WAL as that won't be required downstream.
+	 *
+	 * The conflict detection slot is not affected by concerns related to WALs
+	 * as it only retains the dead tuples. It is created here for consistency.
+	 * Note that the new conflict detection slot uses the latest transaction
+	 * ID as xmin, so it cannot protect dead tuples that existed before the
+	 * upgrade. Additionally, commit timestamps and origin data are not
+	 * preserved during the upgrade. So, even after creating the slot, the
+	 * upgraded subscriber may be unable to detect conflicts or log relevant
+	 * commit timestamps and origins when applying changes from the publisher
+	 * occurred before the upgrade especially if those changes were not
+	 * replicated. It can only protect tuples that might be deleted after the
+	 * new cluster starts.
 	 */
-	if (count_old_cluster_logical_slots())
+	if (migrate_logical_slots || old_cluster.sub_retain_dead_tuples)
 	{
 		start_postmaster(&new_cluster, true);
-		create_logical_replication_slots();
+
+		if (migrate_logical_slots)
+			create_logical_replication_slots();
+
+		if (old_cluster.sub_retain_dead_tuples)
+			create_conflict_detection_slot();
+
 		stop_postmaster(false);
 	}
 
@@ -1025,3 +1048,24 @@ create_logical_replication_slots(void)
 
 	return;
 }
+
+/*
+ * create_conflict_detection_slot()
+ *
+ * Create a replication slot to retain information necessary for conflict
+ * detection such as dead tuples, commit timestamps, and origins, for migrated
+ * subscriptions with retain_dead_tuples enabled.
+ */
+static void
+create_conflict_detection_slot(void)
+{
+	PGconn	   *conn_new_template1;
+
+	prep_status("Creating the replication conflict detection slot");
+
+	conn_new_template1 = connectToServer(&new_cluster, "template1");
+	PQclear(executeQueryOrDie(conn_new_template1, "SELECT pg_catalog.binary_upgrade_create_conflict_detection_slot()"));
+	PQfinish(conn_new_template1);
+
+	check_ok();
+}
diff --git a/src/bin/pg_upgrade/pg_upgrade.h b/src/bin/pg_upgrade/pg_upgrade.h
index 69c965bb7d09a..0ef47be0dc199 100644
--- a/src/bin/pg_upgrade/pg_upgrade.h
+++ b/src/bin/pg_upgrade/pg_upgrade.h
@@ -300,8 +300,12 @@ typedef struct
 	uint32		major_version;	/* PG_VERSION of cluster */
 	char		major_version_str[64];	/* string PG_VERSION of cluster */
 	uint32		bin_version;	/* version returned from pg_ctl */
+	char	  **tablespaces;	/* tablespace directories */
+	int			num_tablespaces;
 	const char *tablespace_suffix;	/* directory specification */
 	int			nsubs;			/* number of subscriptions */
+	bool		sub_retain_dead_tuples; /* whether a subscription enables
+										 * retain_dead_tuples. */
 } ClusterInfo;
 
 
@@ -354,8 +358,6 @@ typedef struct
 	const char *progname;		/* complete pathname for this program */
 	char	   *user;			/* username for clusters */
 	bool		user_specified; /* user specified on command-line */
-	char	  **old_tablespaces;	/* tablespaces */
-	int			num_old_tablespaces;
 	LibraryInfo *libraries;		/* loadable libraries */
 	int			num_libraries;
 	ClusterInfo *running_cluster;
@@ -441,7 +443,7 @@ FileNameMap *gen_db_file_maps(DbInfo *old_db,
 							  const char *new_pgdata);
 void		get_db_rel_and_slot_infos(ClusterInfo *cluster);
 int			count_old_cluster_logical_slots(void);
-void		get_subscription_count(ClusterInfo *cluster);
+void		get_subscription_info(ClusterInfo *cluster);
 
 /* option.c */
 
@@ -455,7 +457,7 @@ void		transfer_all_new_tablespaces(DbInfoArr *old_db_arr,
 										 DbInfoArr *new_db_arr, char *old_pgdata, char *new_pgdata);
 void		transfer_all_new_dbs(DbInfoArr *old_db_arr,
 								 DbInfoArr *new_db_arr, char *old_pgdata, char *new_pgdata,
-								 char *old_tablespace);
+								 char *old_tablespace, char *new_tablespace);
 
 /* tablespace.c */
 
@@ -503,7 +505,7 @@ void		parallel_exec_prog(const char *log_file, const char *opt_log_file,
 							   const char *fmt,...) pg_attribute_printf(3, 4);
 void		parallel_transfer_all_new_dbs(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
 										  char *old_pgdata, char *new_pgdata,
-										  char *old_tablespace);
+										  char *old_tablespace, char *new_tablespace);
 bool		reap_child(bool wait_for_child);
 
 /* task.c */
diff --git a/src/bin/pg_upgrade/relfilenumber.c b/src/bin/pg_upgrade/relfilenumber.c
index 8d8e816a01fa4..38c17ceabf222 100644
--- a/src/bin/pg_upgrade/relfilenumber.c
+++ b/src/bin/pg_upgrade/relfilenumber.c
@@ -17,7 +17,7 @@
 #include "common/logging.h"
 #include "pg_upgrade.h"
 
-static void transfer_single_new_db(FileNameMap *maps, int size, char *old_tablespace);
+static void transfer_single_new_db(FileNameMap *maps, int size, char *old_tablespace, char *new_tablespace);
 static void transfer_relfile(FileNameMap *map, const char *type_suffix, bool vm_must_add_frozenbit);
 
 /*
@@ -136,21 +136,22 @@ transfer_all_new_tablespaces(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
 	 */
 	if (user_opts.jobs <= 1)
 		parallel_transfer_all_new_dbs(old_db_arr, new_db_arr, old_pgdata,
-									  new_pgdata, NULL);
+									  new_pgdata, NULL, NULL);
 	else
 	{
 		int			tblnum;
 
 		/* transfer default tablespace */
 		parallel_transfer_all_new_dbs(old_db_arr, new_db_arr, old_pgdata,
-									  new_pgdata, old_pgdata);
+									  new_pgdata, old_pgdata, new_pgdata);
 
-		for (tblnum = 0; tblnum < os_info.num_old_tablespaces; tblnum++)
+		for (tblnum = 0; tblnum < old_cluster.num_tablespaces; tblnum++)
 			parallel_transfer_all_new_dbs(old_db_arr,
 										  new_db_arr,
 										  old_pgdata,
 										  new_pgdata,
-										  os_info.old_tablespaces[tblnum]);
+										  old_cluster.tablespaces[tblnum],
+										  new_cluster.tablespaces[tblnum]);
 		/* reap all children */
 		while (reap_child(true) == true)
 			;
@@ -169,7 +170,8 @@ transfer_all_new_tablespaces(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
  */
 void
 transfer_all_new_dbs(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
-					 char *old_pgdata, char *new_pgdata, char *old_tablespace)
+					 char *old_pgdata, char *new_pgdata,
+					 char *old_tablespace, char *new_tablespace)
 {
 	int			old_dbnum,
 				new_dbnum;
@@ -204,7 +206,7 @@ transfer_all_new_dbs(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
 									new_pgdata);
 		if (n_maps)
 		{
-			transfer_single_new_db(mappings, n_maps, old_tablespace);
+			transfer_single_new_db(mappings, n_maps, old_tablespace, new_tablespace);
 		}
 		/* We allocate something even for n_maps == 0 */
 		pg_free(mappings);
@@ -234,10 +236,10 @@ transfer_all_new_dbs(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
  *	moved_db_dir: Destination for the pg_restore-generated database directory.
  */
 static bool
-prepare_for_swap(const char *old_tablespace, Oid db_oid,
-				 char *old_catalog_dir, char *new_db_dir, char *moved_db_dir)
+prepare_for_swap(const char *old_tablespace, const char *new_tablespace,
+				 Oid db_oid, char *old_catalog_dir, char *new_db_dir,
+				 char *moved_db_dir)
 {
-	const char *new_tablespace;
 	const char *old_tblspc_suffix;
 	const char *new_tblspc_suffix;
 	char		old_tblspc[MAXPGPATH];
@@ -247,24 +249,14 @@ prepare_for_swap(const char *old_tablespace, Oid db_oid,
 	struct stat st;
 
 	if (strcmp(old_tablespace, old_cluster.pgdata) == 0)
-	{
-		new_tablespace = new_cluster.pgdata;
-		new_tblspc_suffix = "/base";
 		old_tblspc_suffix = "/base";
-	}
 	else
-	{
-		/*
-		 * XXX: The below line is a hack to deal with the fact that we
-		 * presently don't have an easy way to find the corresponding new
-		 * tablespace's path.  This will need to be fixed if/when we add
-		 * pg_upgrade support for in-place tablespaces.
-		 */
-		new_tablespace = old_tablespace;
+		old_tblspc_suffix = old_cluster.tablespace_suffix;
 
+	if (strcmp(new_tablespace, new_cluster.pgdata) == 0)
+		new_tblspc_suffix = "/base";
+	else
 		new_tblspc_suffix = new_cluster.tablespace_suffix;
-		old_tblspc_suffix = old_cluster.tablespace_suffix;
-	}
 
 	/* Old and new cluster paths. */
 	snprintf(old_tblspc, sizeof(old_tblspc), "%s%s", old_tablespace, old_tblspc_suffix);
@@ -450,7 +442,7 @@ swap_catalog_files(FileNameMap *maps, int size, const char *old_catalog_dir,
  * during pg_restore.
  */
 static void
-do_swap(FileNameMap *maps, int size, char *old_tablespace)
+do_swap(FileNameMap *maps, int size, char *old_tablespace, char *new_tablespace)
 {
 	char		old_catalog_dir[MAXPGPATH];
 	char		new_db_dir[MAXPGPATH];
@@ -470,21 +462,23 @@ do_swap(FileNameMap *maps, int size, char *old_tablespace)
 	 */
 	if (old_tablespace)
 	{
-		if (prepare_for_swap(old_tablespace, maps[0].db_oid,
+		if (prepare_for_swap(old_tablespace, new_tablespace, maps[0].db_oid,
 							 old_catalog_dir, new_db_dir, moved_db_dir))
 			swap_catalog_files(maps, size,
 							   old_catalog_dir, new_db_dir, moved_db_dir);
 	}
 	else
 	{
-		if (prepare_for_swap(old_cluster.pgdata, maps[0].db_oid,
+		if (prepare_for_swap(old_cluster.pgdata, new_cluster.pgdata, maps[0].db_oid,
 							 old_catalog_dir, new_db_dir, moved_db_dir))
 			swap_catalog_files(maps, size,
 							   old_catalog_dir, new_db_dir, moved_db_dir);
 
-		for (int tblnum = 0; tblnum < os_info.num_old_tablespaces; tblnum++)
+		for (int tblnum = 0; tblnum < old_cluster.num_tablespaces; tblnum++)
 		{
-			if (prepare_for_swap(os_info.old_tablespaces[tblnum], maps[0].db_oid,
+			if (prepare_for_swap(old_cluster.tablespaces[tblnum],
+								 new_cluster.tablespaces[tblnum],
+								 maps[0].db_oid,
 								 old_catalog_dir, new_db_dir, moved_db_dir))
 				swap_catalog_files(maps, size,
 								   old_catalog_dir, new_db_dir, moved_db_dir);
@@ -498,7 +492,8 @@ do_swap(FileNameMap *maps, int size, char *old_tablespace)
  * create links for mappings stored in "maps" array.
  */
 static void
-transfer_single_new_db(FileNameMap *maps, int size, char *old_tablespace)
+transfer_single_new_db(FileNameMap *maps, int size,
+					   char *old_tablespace, char *new_tablespace)
 {
 	int			mapnum;
 	bool		vm_must_add_frozenbit = false;
@@ -520,7 +515,7 @@ transfer_single_new_db(FileNameMap *maps, int size, char *old_tablespace)
 		 */
 		Assert(!vm_must_add_frozenbit);
 
-		do_swap(maps, size, old_tablespace);
+		do_swap(maps, size, old_tablespace, new_tablespace);
 		return;
 	}
 
diff --git a/src/bin/pg_upgrade/server.c b/src/bin/pg_upgrade/server.c
index 873e5b5117bf9..7eb15bc7d5acc 100644
--- a/src/bin/pg_upgrade/server.c
+++ b/src/bin/pg_upgrade/server.c
@@ -241,24 +241,6 @@ start_postmaster(ClusterInfo *cluster, bool report_and_exit_on_error)
 	if (cluster == &new_cluster)
 		appendPQExpBufferStr(&pgoptions, " -c synchronous_commit=off -c fsync=off -c full_page_writes=off");
 
-	/*
-	 * Use max_slot_wal_keep_size as -1 to prevent the WAL removal by the
-	 * checkpointer process.  If WALs required by logical replication slots
-	 * are removed, the slots are unusable.  This setting prevents the
-	 * invalidation of slots during the upgrade. We set this option when
-	 * cluster is PG17 or later because logical replication slots can only be
-	 * migrated since then. Besides, max_slot_wal_keep_size is added in PG13.
-	 */
-	if (GET_MAJOR_VERSION(cluster->major_version) >= 1700)
-		appendPQExpBufferStr(&pgoptions, " -c max_slot_wal_keep_size=-1");
-
-	/*
-	 * Use idle_replication_slot_timeout=0 to prevent slot invalidation due to
-	 * idle_timeout by checkpointer process during upgrade.
-	 */
-	if (GET_MAJOR_VERSION(cluster->major_version) >= 1800)
-		appendPQExpBufferStr(&pgoptions, " -c idle_replication_slot_timeout=0");
-
 	/*
 	 * Use -b to disable autovacuum and logical replication launcher
 	 * (effective in PG17 or later for the latter).
diff --git a/src/bin/pg_upgrade/t/002_pg_upgrade.pl b/src/bin/pg_upgrade/t/002_pg_upgrade.pl
index 7d82593879d57..0b15e38297e2e 100644
--- a/src/bin/pg_upgrade/t/002_pg_upgrade.pl
+++ b/src/bin/pg_upgrade/t/002_pg_upgrade.pl
@@ -375,6 +375,9 @@ sub get_dump_for_comparison
 {
 	my $dstnode = PostgreSQL::Test::Cluster->new('dst_node');
 
+	skip "regress_dump_restore not enabled in PG_TEST_EXTRA"
+	  if (!$ENV{PG_TEST_EXTRA}
+		|| $ENV{PG_TEST_EXTRA} !~ /\bregress_dump_restore\b/);
 	skip "different Postgres versions"
 	  if ($oldnode->pg_version != $dstnode->pg_version);
 	skip "source node not using default install"
diff --git a/src/bin/pg_upgrade/t/004_subscription.pl b/src/bin/pg_upgrade/t/004_subscription.pl
index e46f02c6cc612..77387be0f9d56 100644
--- a/src/bin/pg_upgrade/t/004_subscription.pl
+++ b/src/bin/pg_upgrade/t/004_subscription.pl
@@ -22,13 +22,13 @@
 
 # Initialize the old subscriber node
 my $old_sub = PostgreSQL::Test::Cluster->new('old_sub');
-$old_sub->init;
+$old_sub->init(allows_streaming => 'physical');
 $old_sub->start;
 my $oldbindir = $old_sub->config_data('--bindir');
 
 # Initialize the new subscriber
 my $new_sub = PostgreSQL::Test::Cluster->new('new_sub');
-$new_sub->init;
+$new_sub->init(allows_streaming => 'physical');
 my $newbindir = $new_sub->config_data('--bindir');
 
 # In a VPATH build, we'll be started in the source directory, but we want
@@ -89,6 +89,54 @@
 $old_sub->start;
 $old_sub->safe_psql('postgres', "DROP SUBSCRIPTION regress_sub1;");
 
+# ------------------------------------------------------
+# Check that pg_upgrade fails when max_replication_slots configured in the new
+# cluster is less than the number of logical slots in the old cluster + 1 when
+# subscription's retain_dead_tuples option is enabled.
+# ------------------------------------------------------
+# It is sufficient to use disabled subscription to test upgrade failure.
+
+$publisher->safe_psql('postgres', "CREATE PUBLICATION regress_pub1");
+$old_sub->safe_psql('postgres',
+	"CREATE SUBSCRIPTION regress_sub1 CONNECTION '$connstr' PUBLICATION regress_pub1 WITH (enabled = false, retain_dead_tuples = true)"
+);
+
+$old_sub->stop;
+
+$new_sub->append_conf('postgresql.conf', 'max_replication_slots = 0');
+
+# pg_upgrade will fail because the new cluster has insufficient
+# max_replication_slots.
+command_checks_all(
+	[
+		'pg_upgrade',
+		'--no-sync',
+		'--old-datadir' => $old_sub->data_dir,
+		'--new-datadir' => $new_sub->data_dir,
+		'--old-bindir' => $oldbindir,
+		'--new-bindir' => $newbindir,
+		'--socketdir' => $new_sub->host,
+		'--old-port' => $old_sub->port,
+		'--new-port' => $new_sub->port,
+		$mode,
+		'--check',
+	],
+	1,
+	[
+		qr/"max_replication_slots" \(0\) must be greater than or equal to the number of logical replication slots on the old cluster plus one additional slot required for retaining conflict detection information \(1\)/
+	],
+	[qr//],
+	'run of pg_upgrade where the new cluster has insufficient max_replication_slots'
+);
+
+# Reset max_replication_slots
+$new_sub->append_conf('postgresql.conf', 'max_replication_slots = 10');
+
+# Cleanup
+$publisher->safe_psql('postgres', "DROP PUBLICATION regress_pub1");
+$old_sub->start;
+$old_sub->safe_psql('postgres', "DROP SUBSCRIPTION regress_sub1;");
+
 # ------------------------------------------------------
 # Check that pg_upgrade refuses to run if:
 # a) there's a subscription with tables in a state other than 'r' (ready) or
@@ -200,8 +248,9 @@
 rmtree($new_sub->data_dir . "/pg_upgrade_output.d");
 
 # Verify that the upgrade should be successful with tables in 'ready'/'init'
-# state along with retaining the replication origin's remote lsn, subscription's
-# running status, and failover option.
+# state along with retaining the replication origin's remote lsn,
+# subscription's running status, failover option, and retain_dead_tuples
+# option.
 $publisher->safe_psql(
 	'postgres', qq[
 		CREATE TABLE tab_upgraded1(id int);
@@ -211,7 +260,7 @@
 $old_sub->safe_psql(
 	'postgres', qq[
 		CREATE TABLE tab_upgraded1(id int);
-		CREATE SUBSCRIPTION regress_sub4 CONNECTION '$connstr' PUBLICATION regress_pub4 WITH (failover = true);
+		CREATE SUBSCRIPTION regress_sub4 CONNECTION '$connstr' PUBLICATION regress_pub4 WITH (failover = true, retain_dead_tuples = true);
 ]);
 
 # Wait till the table tab_upgraded1 reaches 'ready' state
@@ -270,7 +319,8 @@
 # Check that pg_upgrade is successful when all tables are in ready or in
 # init state (tab_upgraded1 table is in ready state and tab_upgraded2 table is
 # in init state) along with retaining the replication origin's remote lsn,
-# subscription's running status, and failover option.
+# subscription's running status, failover option, and retain_dead_tuples
+# option.
 # ------------------------------------------------------
 command_ok(
 	[
@@ -293,7 +343,8 @@
 # ------------------------------------------------------
 # Check that the data inserted to the publisher when the new subscriber is down
 # will be replicated once it is started. Also check that the old subscription
-# states and relations origins are all preserved.
+# states and relations origins are all preserved, and that the conflict
+# detection slot is created.
 # ------------------------------------------------------
 $publisher->safe_psql(
 	'postgres', qq[
@@ -303,15 +354,16 @@
 
 $new_sub->start;
 
-# The subscription's running status and failover option should be preserved
-# in the upgraded instance. So regress_sub4 should still have subenabled and
-# subfailover set to true, while regress_sub5 should have both set to false.
+# The subscription's running status, failover option, and retain_dead_tuples
+# option should be preserved in the upgraded instance. So regress_sub4 should
+# still have subenabled, subfailover, and subretaindeadtuples set to true,
+# while regress_sub5 should have both set to false.
 $result = $new_sub->safe_psql('postgres',
-	"SELECT subname, subenabled, subfailover FROM pg_subscription ORDER BY subname"
+	"SELECT subname, subenabled, subfailover, subretaindeadtuples FROM pg_subscription ORDER BY subname"
 );
-is( $result, qq(regress_sub4|t|t
-regress_sub5|f|f),
-	"check that the subscription's running status and failover are preserved"
+is( $result, qq(regress_sub4|t|t|t
+regress_sub5|f|f|f),
+	"check that the subscription's running status, failover, and retain_dead_tuples are preserved"
 );
 
 # Subscription relations should be preserved
@@ -330,6 +382,11 @@
 );
 is($result, qq($remote_lsn), "remote_lsn should have been preserved");
 
+# The conflict detection slot should be created
+$result = $new_sub->safe_psql('postgres',
+	"SELECT xmin IS NOT NULL from pg_replication_slots WHERE slot_name = 'pg_conflict_detection'");
+is($result, qq(t), "conflict detection slot exists");
+
 # Resume the initial sync and wait until all tables of subscription
 # 'regress_sub5' are synchronized
 $new_sub->append_conf('postgresql.conf',
diff --git a/src/bin/pg_upgrade/t/006_transfer_modes.pl b/src/bin/pg_upgrade/t/006_transfer_modes.pl
index 58fe8a8c7dcea..348f402146234 100644
--- a/src/bin/pg_upgrade/t/006_transfer_modes.pl
+++ b/src/bin/pg_upgrade/t/006_transfer_modes.pl
@@ -38,6 +38,13 @@ sub test_mode
 	}
 	$new->init();
 
+	# allow_in_place_tablespaces is available as far back as v10.
+	if ($old->pg_version >= 10)
+	{
+		$new->append_conf('postgresql.conf', "allow_in_place_tablespaces = true");
+		$old->append_conf('postgresql.conf', "allow_in_place_tablespaces = true");
+	}
+
 	# Create a small variety of simple test objects on the old cluster.  We'll
 	# check that these reach the new version after upgrading.
 	$old->start;
@@ -49,8 +56,7 @@ sub test_mode
 	$old->safe_psql('testdb1', "VACUUM FULL test2");
 	$old->safe_psql('testdb1', "CREATE SEQUENCE testseq START 5432");
 
-	# For cross-version tests, we can also check that pg_upgrade handles
-	# tablespaces.
+	# If an old installation is provided, we can test non-in-place tablespaces.
 	if (defined($ENV{oldinstall}))
 	{
 		my $tblspc = PostgreSQL::Test::Utils::tempdir_short();
@@ -64,6 +70,19 @@ sub test_mode
 		$old->safe_psql('testdb2',
 			"CREATE TABLE test4 AS SELECT generate_series(400, 502)");
 	}
+
+	# If the old cluster is >= v10, we can test in-place tablespaces.
+	if ($old->pg_version >= 10)
+	{
+		$old->safe_psql('postgres',
+			"CREATE TABLESPACE inplc_tblspc LOCATION ''");
+		$old->safe_psql('postgres',
+			"CREATE DATABASE testdb3 TABLESPACE inplc_tblspc");
+		$old->safe_psql('postgres',
+			"CREATE TABLE test5 TABLESPACE inplc_tblspc AS SELECT generate_series(503, 606)");
+		$old->safe_psql('testdb3',
+			"CREATE TABLE test6 AS SELECT generate_series(607, 711)");
+	}
 	$old->stop;
 
 	my $result = command_ok_or_fails_like(
@@ -94,8 +113,7 @@ sub test_mode
 		$result = $new->safe_psql('testdb1', "SELECT nextval('testseq')");
 		is($result, '5432', "sequence data after pg_upgrade $mode");
 
-		# For cross-version tests, we should have some objects in a non-default
-		# tablespace.
+		# Tests for non-in-place tablespaces.
 		if (defined($ENV{oldinstall}))
 		{
 			$result =
@@ -105,6 +123,15 @@ sub test_mode
 			  $new->safe_psql('testdb2', "SELECT COUNT(*) FROM test4");
 			is($result, '103', "test4 data after pg_upgrade $mode");
 		}
+
+		# Tests for in-place tablespaces.
+		if ($old->pg_version >= 10)
+		{
+			$result = $new->safe_psql('postgres', "SELECT COUNT(*) FROM test5");
+			is($result, '104', "test5 data after pg_upgrade $mode");
+			$result = $new->safe_psql('testdb3', "SELECT COUNT(*) FROM test6");
+			is($result, '105', "test6 data after pg_upgrade $mode");
+		}
 		$new->stop;
 	}
 
diff --git a/src/bin/pg_upgrade/tablespace.c b/src/bin/pg_upgrade/tablespace.c
index 3520a75ba317d..151d74e17349b 100644
--- a/src/bin/pg_upgrade/tablespace.c
+++ b/src/bin/pg_upgrade/tablespace.c
@@ -23,10 +23,20 @@ init_tablespaces(void)
 	set_tablespace_directory_suffix(&old_cluster);
 	set_tablespace_directory_suffix(&new_cluster);
 
-	if (os_info.num_old_tablespaces > 0 &&
+	if (old_cluster.num_tablespaces > 0 &&
 		strcmp(old_cluster.tablespace_suffix, new_cluster.tablespace_suffix) == 0)
-		pg_fatal("Cannot upgrade to/from the same system catalog version when\n"
-				 "using tablespaces.");
+	{
+		for (int i = 0; i < old_cluster.num_tablespaces; i++)
+		{
+			/*
+			 * In-place tablespaces are okay for same-version upgrades because
+			 * their paths will differ between clusters.
+			 */
+			if (strcmp(old_cluster.tablespaces[i], new_cluster.tablespaces[i]) == 0)
+				pg_fatal("Cannot upgrade to/from the same system catalog version when\n"
+						 "using tablespaces.");
+		}
+	}
 }
 
 
@@ -53,19 +63,48 @@ get_tablespace_paths(void)
 
 	res = executeQueryOrDie(conn, "%s", query);
 
-	if ((os_info.num_old_tablespaces = PQntuples(res)) != 0)
-		os_info.old_tablespaces =
-			(char **) pg_malloc(os_info.num_old_tablespaces * sizeof(char *));
+	old_cluster.num_tablespaces = PQntuples(res);
+	new_cluster.num_tablespaces = PQntuples(res);
+
+	if (PQntuples(res) != 0)
+	{
+		old_cluster.tablespaces =
+			(char **) pg_malloc(old_cluster.num_tablespaces * sizeof(char *));
+		new_cluster.tablespaces =
+			(char **) pg_malloc(new_cluster.num_tablespaces * sizeof(char *));
+	}
 	else
-		os_info.old_tablespaces = NULL;
+	{
+		old_cluster.tablespaces = NULL;
+		new_cluster.tablespaces = NULL;
+	}
 
 	i_spclocation = PQfnumber(res, "spclocation");
 
-	for (tblnum = 0; tblnum < os_info.num_old_tablespaces; tblnum++)
+	for (tblnum = 0; tblnum < old_cluster.num_tablespaces; tblnum++)
 	{
 		struct stat statBuf;
+		char	   *spcloc = PQgetvalue(res, tblnum, i_spclocation);
 
-		os_info.old_tablespaces[tblnum] = pg_strdup(PQgetvalue(res, tblnum, i_spclocation));
+		/*
+		 * For now, we do not expect non-in-place tablespaces to move during
+		 * upgrade.  If that changes, it will likely become necessary to run
+		 * the above query on the new cluster, too.
+		 *
+		 * pg_tablespace_location() returns absolute paths for non-in-place
+		 * tablespaces and relative paths for in-place ones, so we use
+		 * is_absolute_path() to distinguish between them.
+		 */
+		if (is_absolute_path(PQgetvalue(res, tblnum, i_spclocation)))
+		{
+			old_cluster.tablespaces[tblnum] = pg_strdup(spcloc);
+			new_cluster.tablespaces[tblnum] = old_cluster.tablespaces[tblnum];
+		}
+		else
+		{
+			old_cluster.tablespaces[tblnum] = psprintf("%s/%s", old_cluster.pgdata, spcloc);
+			new_cluster.tablespaces[tblnum] = psprintf("%s/%s", new_cluster.pgdata, spcloc);
+		}
 
 		/*
 		 * Check that the tablespace path exists and is a directory.
@@ -76,21 +115,21 @@ get_tablespace_paths(void)
 		 * that contains user tablespaces is moved as part of pg_upgrade
 		 * preparation and the symbolic links are not updated.
 		 */
-		if (stat(os_info.old_tablespaces[tblnum], &statBuf) != 0)
+		if (stat(old_cluster.tablespaces[tblnum], &statBuf) != 0)
 		{
 			if (errno == ENOENT)
 				report_status(PG_FATAL,
 							  "tablespace directory \"%s\" does not exist",
-							  os_info.old_tablespaces[tblnum]);
+							  old_cluster.tablespaces[tblnum]);
 			else
 				report_status(PG_FATAL,
 							  "could not stat tablespace directory \"%s\": %m",
-							  os_info.old_tablespaces[tblnum]);
+							  old_cluster.tablespaces[tblnum]);
 		}
 		if (!S_ISDIR(statBuf.st_mode))
 			report_status(PG_FATAL,
 						  "tablespace path \"%s\" is not a directory",
-						  os_info.old_tablespaces[tblnum]);
+						  old_cluster.tablespaces[tblnum]);
 	}
 
 	PQclear(res);
diff --git a/src/bin/pg_verifybackup/meson.build b/src/bin/pg_verifybackup/meson.build
index 9567d55500d0a..f45ea790d8e17 100644
--- a/src/bin/pg_verifybackup/meson.build
+++ b/src/bin/pg_verifybackup/meson.build
@@ -23,10 +23,10 @@ tests += {
   'sd': meson.current_source_dir(),
   'bd': meson.current_build_dir(),
   'tap': {
-    'env': {'GZIP_PROGRAM': gzip.found() ? gzip.path() : '',
-            'TAR': tar.found() ? tar.path() : '',
-            'LZ4': program_lz4.found() ? program_lz4.path() : '',
-            'ZSTD': program_zstd.found() ? program_zstd.path() : ''},
+    'env': {'GZIP_PROGRAM': gzip.found() ? gzip.full_path() : '',
+            'TAR': tar.found() ? tar.full_path() : '',
+            'LZ4': program_lz4.found() ? program_lz4.full_path() : '',
+            'ZSTD': program_zstd.found() ? program_zstd.full_path() : ''},
     'tests': [
       't/001_basic.pl',
       't/002_algorithm.pl',
diff --git a/src/bin/pg_verifybackup/pg_verifybackup.c b/src/bin/pg_verifybackup/pg_verifybackup.c
index 48994ef9bc6fc..5e6c13bb92168 100644
--- a/src/bin/pg_verifybackup/pg_verifybackup.c
+++ b/src/bin/pg_verifybackup/pg_verifybackup.c
@@ -1207,7 +1207,7 @@ parse_required_wal(verifier_context *context, char *pg_waldump_path,
 	{
 		char	   *pg_waldump_cmd;
 
-		pg_waldump_cmd = psprintf("\"%s\" --quiet --path=\"%s\" --timeline=%u --start=%X/%X --end=%X/%X\n",
+		pg_waldump_cmd = psprintf("\"%s\" --quiet --path=\"%s\" --timeline=%u --start=%X/%08X --end=%X/%08X\n",
 								  pg_waldump_path, wal_directory, this_wal_range->tli,
 								  LSN_FORMAT_ARGS(this_wal_range->start_lsn),
 								  LSN_FORMAT_ARGS(this_wal_range->end_lsn));
diff --git a/src/bin/pg_verifybackup/t/008_untar.pl b/src/bin/pg_verifybackup/t/008_untar.pl
index deed3ec247d2d..bc3d6b352ad50 100644
--- a/src/bin/pg_verifybackup/t/008_untar.pl
+++ b/src/bin/pg_verifybackup/t/008_untar.pl
@@ -16,6 +16,22 @@
 $primary->init(allows_streaming => 1);
 $primary->start;
 
+# Create file with some random data and an arbitrary size, useful to check
+# the solidity of the compression and decompression logic.  The size of the
+# file is chosen to be around 640kB.  This has proven to be large enough to
+# detect some issues related to LZ4, and low enough to not impact the runtime
+# of the test significantly.
+my $junk_data = $primary->safe_psql(
+	'postgres', qq(
+		SELECT string_agg(encode(sha256(i::bytea), 'hex'), '')
+		FROM generate_series(1, 10240) s(i);));
+my $data_dir = $primary->data_dir;
+my $junk_file = "$data_dir/junk";
+open my $jf, '>', $junk_file
+  or die "Could not create junk file: $!";
+print $jf $junk_data;
+close $jf;
+
 # Create a tablespace directory.
 my $source_ts_path = PostgreSQL::Test::Utils::tempdir_short();
 
@@ -52,6 +68,12 @@
 		'backup_archive' => [ 'base.tar.lz4', "$tsoid.tar.lz4" ],
 		'enabled' => check_pg_config("#define USE_LZ4 1")
 	},
+	{
+		'compression_method' => 'lz4',
+		'backup_flags' => [ '--compress', 'server-lz4:5' ],
+		'backup_archive' => [ 'base.tar.lz4', "$tsoid.tar.lz4" ],
+		'enabled' => check_pg_config("#define USE_LZ4 1")
+	},
 	{
 		'compression_method' => 'zstd',
 		'backup_flags' => [ '--compress', 'server-zstd' ],
diff --git a/src/bin/pg_verifybackup/t/010_client_untar.pl b/src/bin/pg_verifybackup/t/010_client_untar.pl
index d8d2b06c7ee86..b62faeb5acfab 100644
--- a/src/bin/pg_verifybackup/t/010_client_untar.pl
+++ b/src/bin/pg_verifybackup/t/010_client_untar.pl
@@ -15,6 +15,22 @@
 $primary->init(allows_streaming => 1);
 $primary->start;
 
+# Create file with some random data and an arbitrary size, useful to check
+# the solidity of the compression and decompression logic.  The size of the
+# file is chosen to be around 640kB.  This has proven to be large enough to
+# detect some issues related to LZ4, and low enough to not impact the runtime
+# of the test significantly.
+my $junk_data = $primary->safe_psql(
+	'postgres', qq(
+		SELECT string_agg(encode(sha256(i::bytea), 'hex'), '')
+		FROM generate_series(1, 10240) s(i);));
+my $data_dir = $primary->data_dir;
+my $junk_file = "$data_dir/junk";
+open my $jf, '>', $junk_file
+  or die "Could not create junk file: $!";
+print $jf $junk_data;
+close $jf;
+
 my $backup_path = $primary->backup_dir . '/client-backup';
 my $extract_path = $primary->backup_dir . '/extracted-backup';
 
@@ -37,6 +53,12 @@
 		'backup_archive' => 'base.tar.lz4',
 		'enabled' => check_pg_config("#define USE_LZ4 1")
 	},
+	{
+		'compression_method' => 'lz4',
+		'backup_flags' => [ '--compress', 'client-lz4:1' ],
+		'backup_archive' => 'base.tar.lz4',
+		'enabled' => check_pg_config("#define USE_LZ4 1")
+	},
 	{
 		'compression_method' => 'zstd',
 		'backup_flags' => [ '--compress', 'client-zstd:5' ],
diff --git a/src/bin/pg_waldump/pg_waldump.c b/src/bin/pg_waldump/pg_waldump.c
index 51fb76efc489e..13d3ec2f5be3c 100644
--- a/src/bin/pg_waldump/pg_waldump.c
+++ b/src/bin/pg_waldump/pg_waldump.c
@@ -656,7 +656,7 @@ XLogDumpDisplayStats(XLogDumpConfig *config, XLogStats *stats)
 	}
 	total_len = total_rec_len + total_fpi_len;
 
-	printf("WAL statistics between %X/%X and %X/%X:\n",
+	printf("WAL statistics between %X/%08X and %X/%08X:\n",
 		   LSN_FORMAT_ARGS(stats->startptr), LSN_FORMAT_ARGS(stats->endptr));
 
 	/*
@@ -904,7 +904,7 @@ main(int argc, char **argv)
 				config.filter_by_extended = true;
 				break;
 			case 'e':
-				if (sscanf(optarg, "%X/%X", &xlogid, &xrecoff) != 2)
+				if (sscanf(optarg, "%X/%08X", &xlogid, &xrecoff) != 2)
 				{
 					pg_log_error("invalid WAL location: \"%s\"",
 								 optarg);
@@ -1002,7 +1002,7 @@ main(int argc, char **argv)
 				config.filter_by_extended = true;
 				break;
 			case 's':
-				if (sscanf(optarg, "%X/%X", &xlogid, &xrecoff) != 2)
+				if (sscanf(optarg, "%X/%08X", &xlogid, &xrecoff) != 2)
 				{
 					pg_log_error("invalid WAL location: \"%s\"",
 								 optarg);
@@ -1140,7 +1140,7 @@ main(int argc, char **argv)
 			XLogSegNoOffsetToRecPtr(segno, 0, WalSegSz, private.startptr);
 		else if (!XLByteInSeg(private.startptr, segno, WalSegSz))
 		{
-			pg_log_error("start WAL location %X/%X is not inside file \"%s\"",
+			pg_log_error("start WAL location %X/%08X is not inside file \"%s\"",
 						 LSN_FORMAT_ARGS(private.startptr),
 						 fname);
 			goto bad_argument;
@@ -1182,7 +1182,7 @@ main(int argc, char **argv)
 		if (!XLByteInSeg(private.endptr, segno, WalSegSz) &&
 			private.endptr != (segno + 1) * WalSegSz)
 		{
-			pg_log_error("end WAL location %X/%X is not inside file \"%s\"",
+			pg_log_error("end WAL location %X/%08X is not inside file \"%s\"",
 						 LSN_FORMAT_ARGS(private.endptr),
 						 argv[argc - 1]);
 			goto bad_argument;
@@ -1214,7 +1214,7 @@ main(int argc, char **argv)
 	first_record = XLogFindNextRecord(xlogreader_state, private.startptr);
 
 	if (first_record == InvalidXLogRecPtr)
-		pg_fatal("could not find a valid record after %X/%X",
+		pg_fatal("could not find a valid record after %X/%08X",
 				 LSN_FORMAT_ARGS(private.startptr));
 
 	/*
@@ -1224,8 +1224,8 @@ main(int argc, char **argv)
 	 */
 	if (first_record != private.startptr &&
 		XLogSegmentOffset(private.startptr, WalSegSz) != 0)
-		pg_log_info(ngettext("first record is after %X/%X, at %X/%X, skipping over %u byte",
-							 "first record is after %X/%X, at %X/%X, skipping over %u bytes",
+		pg_log_info(ngettext("first record is after %X/%08X, at %X/%08X, skipping over %u byte",
+							 "first record is after %X/%08X, at %X/%08X, skipping over %u bytes",
 							 (first_record - private.startptr)),
 					LSN_FORMAT_ARGS(private.startptr),
 					LSN_FORMAT_ARGS(first_record),
@@ -1309,7 +1309,7 @@ main(int argc, char **argv)
 		exit(0);
 
 	if (errormsg)
-		pg_fatal("error in WAL record at %X/%X: %s",
+		pg_fatal("error in WAL record at %X/%08X: %s",
 				 LSN_FORMAT_ARGS(xlogreader_state->ReadRecPtr),
 				 errormsg);
 
diff --git a/src/bin/pg_walsummary/t/002_blocks.pl b/src/bin/pg_walsummary/t/002_blocks.pl
index 270332780a453..0f98c7df82e6c 100644
--- a/src/bin/pg_walsummary/t/002_blocks.pl
+++ b/src/bin/pg_walsummary/t/002_blocks.pl
@@ -47,11 +47,12 @@
 ok($result, "WAL summarization caught up after insert");
 
 # The WAL summarizer should have generated some IO statistics.
-my $stats_reads = $node1->safe_psql(
+$node1->poll_query_until(
 	'postgres',
-	qq{SELECT sum(reads) > 0 FROM pg_stat_io
-   WHERE backend_type = 'walsummarizer' AND object = 'wal'});
-is($stats_reads, 't', "WAL summarizer generates statistics for WAL reads");
+	q{SELECT sum(reads) > 0 FROM pg_stat_io
+   WHERE backend_type = 'walsummarizer' AND object = 'wal'})
+  or die
+  "Timed out while waiting for WAL summarizer to generate statistics for WAL reads";
 
 # Find the highest LSN that is summarized on disk.
 my $summarized_lsn = $node1->safe_psql('postgres', <<EOM);
diff --git a/src/bin/pgbench/pgbench.c b/src/bin/pgbench/pgbench.c
index 497a936c141f3..125f3c7bbbe5b 100644
--- a/src/bin/pgbench/pgbench.c
+++ b/src/bin/pgbench/pgbench.c
@@ -3495,6 +3495,8 @@ doRetry(CState *st, pg_time_usec_t *now)
 static int
 discardUntilSync(CState *st)
 {
+	bool		received_sync = false;
+
 	/* send a sync */
 	if (!PQpipelineSync(st->con))
 	{
@@ -3509,10 +3511,21 @@ discardUntilSync(CState *st)
 		PGresult   *res = PQgetResult(st->con);
 
 		if (PQresultStatus(res) == PGRES_PIPELINE_SYNC)
+			received_sync = true;
+		else if (received_sync)
 		{
-			PQclear(res);
-			res = PQgetResult(st->con);
+			/*
+			 * PGRES_PIPELINE_SYNC must be followed by another
+			 * PGRES_PIPELINE_SYNC or NULL; otherwise, assert failure.
+			 */
 			Assert(res == NULL);
+
+			/*
+			 * Reset ongoing sync count to 0 since all PGRES_PIPELINE_SYNC
+			 * results have been discarded.
+			 */
+			st->num_syncs = 0;
+			PQclear(res);
 			break;
 		}
 		PQclear(res);
diff --git a/src/bin/pgbench/t/002_pgbench_no_server.pl b/src/bin/pgbench/t/002_pgbench_no_server.pl
index f975c73dd758a..2cc59cc8140c3 100644
--- a/src/bin/pgbench/t/002_pgbench_no_server.pl
+++ b/src/bin/pgbench/t/002_pgbench_no_server.pl
@@ -233,21 +233,9 @@ sub pgbench_scripts
 		'pgbench option error: ' . $name);
 }
 
-# Help
-pgbench(
-	'--help', 0,
-	[
-		qr{benchmarking tool for PostgreSQL},
-		qr{Usage},
-		qr{Initialization options:},
-		qr{Common options:},
-		qr{Report bugs to}
-	],
-	[qr{^$}],
-	'pgbench help');
-
-# Version
-pgbench('-V', 0, [qr{^pgbench .PostgreSQL. }], [qr{^$}], 'pgbench version');
+program_help_ok('pgbench');
+program_version_ok('pgbench');
+program_options_handling_ok('pgbench');
 
 # list of builtins
 pgbench(
diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index 9fcd2db832656..0e00d73487c33 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -4480,6 +4480,8 @@ SyncVariables(void)
 {
 	char		vbuf[32];
 	const char *server_version;
+	char	   *service_name;
+	char	   *service_file;
 
 	/* get stuff from connection */
 	pset.encoding = PQclientEncoding(pset.db);
@@ -4489,12 +4491,21 @@ SyncVariables(void)
 	setFmtEncoding(pset.encoding);
 
 	SetVariable(pset.vars, "DBNAME", PQdb(pset.db));
-	SetVariable(pset.vars, "SERVICE", PQservice(pset.db));
 	SetVariable(pset.vars, "USER", PQuser(pset.db));
 	SetVariable(pset.vars, "HOST", PQhost(pset.db));
 	SetVariable(pset.vars, "PORT", PQport(pset.db));
 	SetVariable(pset.vars, "ENCODING", pg_encoding_to_char(pset.encoding));
 
+	service_name = get_conninfo_value("service");
+	SetVariable(pset.vars, "SERVICE", service_name);
+	if (service_name)
+		pg_free(service_name);
+
+	service_file = get_conninfo_value("servicefile");
+	SetVariable(pset.vars, "SERVICEFILE", service_file);
+	if (service_file)
+		pg_free(service_file);
+
 	/* this bit should match connection_warnings(): */
 	/* Try to get full text form of version, might include "devel" etc */
 	server_version = PQparameterStatus(pset.db, "server_version");
@@ -4524,6 +4535,7 @@ UnsyncVariables(void)
 {
 	SetVariable(pset.vars, "DBNAME", NULL);
 	SetVariable(pset.vars, "SERVICE", NULL);
+	SetVariable(pset.vars, "SERVICEFILE", NULL);
 	SetVariable(pset.vars, "USER", NULL);
 	SetVariable(pset.vars, "HOST", NULL);
 	SetVariable(pset.vars, "PORT", NULL);
diff --git a/src/bin/psql/common.c b/src/bin/psql/common.c
index d2c0a49c46c04..cd329ade12b5d 100644
--- a/src/bin/psql/common.c
+++ b/src/bin/psql/common.c
@@ -2531,6 +2531,41 @@ session_username(void)
 		return PQuser(pset.db);
 }
 
+/*
+ * Return the value of option for keyword in the current connection.
+ *
+ * The caller is responsible for freeing the result value allocated.
+ */
+char *
+get_conninfo_value(const char *keyword)
+{
+	PQconninfoOption *opts;
+	PQconninfoOption *serviceopt = NULL;
+	char	   *res = NULL;
+
+	if (pset.db == NULL)
+		return NULL;
+
+	opts = PQconninfo(pset.db);
+	if (opts == NULL)
+		return NULL;
+
+	for (PQconninfoOption *opt = opts; opt->keyword != NULL; ++opt)
+	{
+		if (strcmp(opt->keyword, keyword) == 0)
+		{
+			serviceopt = opt;
+			break;
+		}
+	}
+
+	/* Take a copy of the value, as it is freed by PQconninfoFree(). */
+	if (serviceopt && serviceopt->val != NULL)
+		res = pg_strdup(serviceopt->val);
+	PQconninfoFree(opts);
+
+	return res;
+}
 
 /* expand_tilde
  *
diff --git a/src/bin/psql/common.h b/src/bin/psql/common.h
index 7f1a23de1e82d..64762ab981755 100644
--- a/src/bin/psql/common.h
+++ b/src/bin/psql/common.h
@@ -39,6 +39,7 @@ extern bool SendQuery(const char *query);
 extern bool is_superuser(void);
 extern bool standard_strings(void);
 extern const char *session_username(void);
+extern char *get_conninfo_value(const char *keyword);
 
 extern void expand_tilde(char **filename);
 extern void clean_extended_state(void);
diff --git a/src/bin/psql/describe.c b/src/bin/psql/describe.c
index dd25d2fe7b8a7..7a06af48842d8 100644
--- a/src/bin/psql/describe.c
+++ b/src/bin/psql/describe.c
@@ -6746,7 +6746,7 @@ describeSubscriptions(const char *pattern, bool verbose)
 	printQueryOpt myopt = pset.popt;
 	static const bool translate_columns[] = {false, false, false, false,
 		false, false, false, false, false, false, false, false, false, false,
-	false};
+	false, false};
 
 	if (pset.sversion < 100000)
 	{
@@ -6814,6 +6814,10 @@ describeSubscriptions(const char *pattern, bool verbose)
 			appendPQExpBuffer(&buf,
 							  ", subfailover AS \"%s\"\n",
 							  gettext_noop("Failover"));
+		if (pset.sversion >= 190000)
+			appendPQExpBuffer(&buf,
+							  ", subretaindeadtuples AS \"%s\"\n",
+							  gettext_noop("Retain dead tuples"));
 
 		appendPQExpBuffer(&buf,
 						  ",  subsynccommit AS \"%s\"\n"
diff --git a/src/bin/psql/help.c b/src/bin/psql/help.c
index a2e009ab9bea7..8c62729a0d124 100644
--- a/src/bin/psql/help.c
+++ b/src/bin/psql/help.c
@@ -748,7 +748,7 @@ void
 print_copyright(void)
 {
 	puts("PostgreSQL Database Management System\n"
-		 "(formerly known as Postgres, then as Postgres95)\n\n"
+		 "(also known as Postgres, formerly known as Postgres95)\n\n"
 		 "Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group\n\n"
 		 "Portions Copyright (c) 1994, The Regents of the University of California\n\n"
 		 "Permission to use, copy, modify, and distribute this software and its\n"
diff --git a/src/bin/psql/prompt.c b/src/bin/psql/prompt.c
index 3aa7d2d06c80e..b08d7328fbfe7 100644
--- a/src/bin/psql/prompt.c
+++ b/src/bin/psql/prompt.c
@@ -169,8 +169,12 @@ get_prompt(promptStatus_t status, ConditionalStack cstack)
 					break;
 					/* service name */
 				case 's':
-					if (pset.db && PQservice(pset.db))
-						strlcpy(buf, PQservice(pset.db), sizeof(buf));
+					{
+						const char *service_name = GetVariable(pset.vars, "SERVICE");
+
+						if (service_name)
+							strlcpy(buf, service_name, sizeof(buf));
+					}
 					break;
 					/* backend pid */
 				case 'p':
diff --git a/src/bin/psql/tab-complete.in.c b/src/bin/psql/tab-complete.in.c
index 908eef97c6e28..1f2ca946fc500 100644
--- a/src/bin/psql/tab-complete.in.c
+++ b/src/bin/psql/tab-complete.in.c
@@ -889,6 +889,14 @@ static const SchemaQuery Query_for_list_of_analyzables = {
 	.result = "c.relname",
 };
 
+/*
+ * Relations supporting COPY TO/FROM are currently almost the same as
+ * those supporting ANALYZE. Although views with INSTEAD OF INSERT triggers
+ * can be used with COPY FROM, they are rarely used for this purpose,
+ * so plain views are intentionally excluded from this tab completion.
+ */
+#define Query_for_list_of_tables_for_copy Query_for_list_of_analyzables
+
 /* Relations supporting index creation */
 static const SchemaQuery Query_for_list_of_indexables = {
 	.catname = "pg_catalog.pg_class c",
@@ -1002,7 +1010,7 @@ static const SchemaQuery Query_for_trigger_of_table = {
 
 #define Query_for_list_of_database_vars \
 "SELECT conf FROM ("\
-"       SELECT setdatabase, pg_catalog.split_part(unnest(setconfig),'=',1) conf"\
+"       SELECT setdatabase, pg_catalog.split_part(pg_catalog.unnest(setconfig),'=',1) conf"\
 "         FROM pg_db_role_setting "\
 "       ) s, pg_database d "\
 " WHERE s.setdatabase = d.oid "\
@@ -1078,9 +1086,12 @@ Keywords_for_list_of_owner_roles, "PUBLIC"
 "  WHERE usename LIKE '%s'"
 
 #define Query_for_list_of_user_vars \
-" SELECT pg_catalog.split_part(pg_catalog.unnest(rolconfig),'=',1) "\
-"   FROM pg_catalog.pg_roles "\
-"  WHERE rolname LIKE '%s'"
+"SELECT conf FROM ("\
+"       SELECT rolname, pg_catalog.split_part(pg_catalog.unnest(rolconfig),'=',1) conf"\
+"         FROM pg_catalog.pg_roles"\
+"       ) s"\
+"  WHERE s.conf like '%s' "\
+"    AND s.rolname LIKE '%s'"
 
 #define Query_for_list_of_access_methods \
 " SELECT amname "\
@@ -1190,6 +1201,19 @@ Alter_procedure_options, "COST", "IMMUTABLE", "LEAKPROOF", "NOT LEAKPROOF", \
 Alter_routine_options, "CALLED ON NULL INPUT", "RETURNS NULL ON NULL INPUT", \
 "STRICT", "SUPPORT"
 
+/* COPY options shared between FROM and TO */
+#define Copy_common_options \
+"DELIMITER", "ENCODING", "ESCAPE", "FORMAT", "HEADER", "NULL", "QUOTE"
+
+/* COPY FROM options */
+#define Copy_from_options \
+Copy_common_options, "DEFAULT", "FORCE_NOT_NULL", "FORCE_NULL", "FREEZE", \
+"LOG_VERBOSITY", "ON_ERROR", "REJECT_LIMIT"
+
+/* COPY TO options */
+#define Copy_to_options \
+Copy_common_options, "FORCE_QUOTE"
+
 /*
  * These object types were introduced later than our support cutoff of
  * server version 9.2.  We use the VersionedQuery infrastructure so that
@@ -2298,8 +2322,9 @@ match_previous_words(int pattern_id,
 	/* ALTER SUBSCRIPTION <name> SET ( */
 	else if (Matches("ALTER", "SUBSCRIPTION", MatchAny, MatchAnyN, "SET", "("))
 		COMPLETE_WITH("binary", "disable_on_error", "failover", "origin",
-					  "password_required", "run_as_owner", "slot_name",
-					  "streaming", "synchronous_commit", "two_phase");
+					  "password_required", "retain_dead_tuples",
+					  "run_as_owner", "slot_name", "streaming",
+					  "synchronous_commit", "two_phase");
 	/* ALTER SUBSCRIPTION <name> SKIP ( */
 	else if (Matches("ALTER", "SUBSCRIPTION", MatchAny, MatchAnyN, "SKIP", "("))
 		COMPLETE_WITH("lsn");
@@ -2495,7 +2520,10 @@ match_previous_words(int pattern_id,
 
 	/* ALTER USER,ROLE <name> RESET */
 	else if (Matches("ALTER", "USER|ROLE", MatchAny, "RESET"))
+	{
+		set_completion_reference(prev2_wd);
 		COMPLETE_WITH_QUERY_PLUS(Query_for_list_of_user_vars, "ALL");
+	}
 
 	/* ALTER USER,ROLE <name> WITH */
 	else if (Matches("ALTER", "USER|ROLE", MatchAny, "WITH"))
@@ -2725,17 +2753,24 @@ match_previous_words(int pattern_id,
 	/* ALTER TABLE xxx ADD */
 	else if (Matches("ALTER", "TABLE", MatchAny, "ADD"))
 	{
-		/* make sure to keep this list and the !Matches() below in sync */
-		COMPLETE_WITH("COLUMN", "CONSTRAINT", "CHECK", "UNIQUE", "PRIMARY KEY",
-					  "EXCLUDE", "FOREIGN KEY");
+		/*
+		 * make sure to keep this list and the MatchAnyExcept() below in sync
+		 */
+		COMPLETE_WITH("COLUMN", "CONSTRAINT", "CHECK (", "NOT NULL", "UNIQUE",
+					  "PRIMARY KEY", "EXCLUDE", "FOREIGN KEY");
 	}
 	/* ALTER TABLE xxx ADD [COLUMN] yyy */
 	else if (Matches("ALTER", "TABLE", MatchAny, "ADD", "COLUMN", MatchAny) ||
-			 Matches("ALTER", "TABLE", MatchAny, "ADD", MatchAnyExcept("COLUMN|CONSTRAINT|CHECK|UNIQUE|PRIMARY|EXCLUDE|FOREIGN")))
+			 Matches("ALTER", "TABLE", MatchAny, "ADD", MatchAnyExcept("COLUMN|CONSTRAINT|CHECK|UNIQUE|PRIMARY|NOT|EXCLUDE|FOREIGN")))
 		COMPLETE_WITH_SCHEMA_QUERY(Query_for_list_of_datatypes);
 	/* ALTER TABLE xxx ADD CONSTRAINT yyy */
 	else if (Matches("ALTER", "TABLE", MatchAny, "ADD", "CONSTRAINT", MatchAny))
-		COMPLETE_WITH("CHECK", "UNIQUE", "PRIMARY KEY", "EXCLUDE", "FOREIGN KEY");
+		COMPLETE_WITH("CHECK (", "NOT NULL", "UNIQUE", "PRIMARY KEY", "EXCLUDE", "FOREIGN KEY");
+	/* ALTER TABLE xxx ADD NOT NULL */
+	else if (Matches("ALTER", "TABLE", MatchAny, "ADD", "NOT", "NULL"))
+		COMPLETE_WITH_ATTR(prev4_wd);
+	else if (Matches("ALTER", "TABLE", MatchAny, "ADD", "CONSTRAINT", MatchAny, "NOT", "NULL"))
+		COMPLETE_WITH_ATTR(prev6_wd);
 	/* ALTER TABLE xxx ADD [CONSTRAINT yyy] (PRIMARY KEY|UNIQUE) */
 	else if (Matches("ALTER", "TABLE", MatchAny, "ADD", "PRIMARY", "KEY") ||
 			 Matches("ALTER", "TABLE", MatchAny, "ADD", "UNIQUE") ||
@@ -3125,6 +3160,22 @@ match_previous_words(int pattern_id,
 		COMPLETE_WITH_VERSIONED_SCHEMA_QUERY(Query_for_list_of_procedures);
 	else if (Matches("CALL", MatchAny))
 		COMPLETE_WITH("(");
+/* CHECKPOINT */
+	else if (Matches("CHECKPOINT"))
+		COMPLETE_WITH("(");
+	else if (HeadMatches("CHECKPOINT", "(*") &&
+			 !HeadMatches("CHECKPOINT", "(*)"))
+	{
+		/*
+		 * This fires if we're in an unfinished parenthesized option list.
+		 * get_previous_words treats a completed parenthesized option list as
+		 * one word, so the above test is correct.
+		 */
+		if (ends_with(prev_wd, '(') || ends_with(prev_wd, ','))
+			COMPLETE_WITH("MODE", "FLUSH_UNLOGGED");
+		else if (TailMatches("MODE"))
+			COMPLETE_WITH("FAST", "SPREAD");
+	}
 /* CLOSE */
 	else if (Matches("CLOSE"))
 		COMPLETE_WITH_QUERY_PLUS(Query_for_list_of_cursors,
@@ -3255,7 +3306,7 @@ match_previous_words(int pattern_id,
 	 * backslash command).
 	 */
 	else if (Matches("COPY|\\copy"))
-		COMPLETE_WITH_SCHEMA_QUERY_PLUS(Query_for_list_of_tables, "(");
+		COMPLETE_WITH_SCHEMA_QUERY_PLUS(Query_for_list_of_tables_for_copy, "(");
 	/* Complete COPY ( with legal query commands */
 	else if (Matches("COPY|\\copy", "("))
 		COMPLETE_WITH("SELECT", "TABLE", "VALUES", "INSERT INTO", "UPDATE", "DELETE FROM", "MERGE INTO", "WITH");
@@ -3284,23 +3335,24 @@ match_previous_words(int pattern_id,
 	else if (Matches("COPY|\\copy", MatchAny, "FROM", MatchAny))
 		COMPLETE_WITH("WITH (", "WHERE");
 
-	/* Complete COPY <sth> FROM|TO filename WITH ( */
-	else if (Matches("COPY|\\copy", MatchAny, "FROM|TO", MatchAny, "WITH", "("))
-		COMPLETE_WITH("FORMAT", "FREEZE", "DELIMITER", "NULL",
-					  "HEADER", "QUOTE", "ESCAPE", "FORCE_QUOTE",
-					  "FORCE_NOT_NULL", "FORCE_NULL", "ENCODING", "DEFAULT",
-					  "ON_ERROR", "LOG_VERBOSITY", "REJECT_LIMIT");
+	/* Complete COPY <sth> FROM filename WITH ( */
+	else if (Matches("COPY|\\copy", MatchAny, "FROM", MatchAny, "WITH", "("))
+		COMPLETE_WITH(Copy_from_options);
+
+	/* Complete COPY <sth> TO filename WITH ( */
+	else if (Matches("COPY|\\copy", MatchAny, "TO", MatchAny, "WITH", "("))
+		COMPLETE_WITH(Copy_to_options);
 
 	/* Complete COPY <sth> FROM|TO filename WITH (FORMAT */
 	else if (Matches("COPY|\\copy", MatchAny, "FROM|TO", MatchAny, "WITH", "(", "FORMAT"))
 		COMPLETE_WITH("binary", "csv", "text");
 
 	/* Complete COPY <sth> FROM filename WITH (ON_ERROR */
-	else if (Matches("COPY|\\copy", MatchAny, "FROM|TO", MatchAny, "WITH", "(", "ON_ERROR"))
+	else if (Matches("COPY|\\copy", MatchAny, "FROM", MatchAny, "WITH", "(", "ON_ERROR"))
 		COMPLETE_WITH("stop", "ignore");
 
 	/* Complete COPY <sth> FROM filename WITH (LOG_VERBOSITY */
-	else if (Matches("COPY|\\copy", MatchAny, "FROM|TO", MatchAny, "WITH", "(", "LOG_VERBOSITY"))
+	else if (Matches("COPY|\\copy", MatchAny, "FROM", MatchAny, "WITH", "(", "LOG_VERBOSITY"))
 		COMPLETE_WITH("silent", "default", "verbose");
 
 	/* Complete COPY <sth> FROM <sth> WITH (<options>) */
@@ -3729,8 +3781,9 @@ match_previous_words(int pattern_id,
 	else if (Matches("CREATE", "SUBSCRIPTION", MatchAnyN, "WITH", "("))
 		COMPLETE_WITH("binary", "connect", "copy_data", "create_slot",
 					  "disable_on_error", "enabled", "failover", "origin",
-					  "password_required", "run_as_owner", "slot_name",
-					  "streaming", "synchronous_commit", "two_phase");
+					  "password_required", "retain_dead_tuples",
+					  "run_as_owner", "slot_name", "streaming",
+					  "synchronous_commit", "two_phase");
 
 /* CREATE TRIGGER --- is allowed inside CREATE SCHEMA, so use TailMatches */
 
@@ -4574,10 +4627,14 @@ match_previous_words(int pattern_id,
 	else if (Matches("ALTER", "DEFAULT", "PRIVILEGES", MatchAnyN, "TO", MatchAny))
 		COMPLETE_WITH("WITH GRANT OPTION");
 	/* Complete "GRANT/REVOKE ... ON * *" with TO/FROM */
-	else if (Matches("GRANT", MatchAnyN, "ON", MatchAny, MatchAny))
-		COMPLETE_WITH("TO");
-	else if (Matches("REVOKE", MatchAnyN, "ON", MatchAny, MatchAny))
-		COMPLETE_WITH("FROM");
+	else if (Matches("GRANT|REVOKE", MatchAnyN, "ON", MatchAny, MatchAny) &&
+			 !TailMatches("FOREIGN", "SERVER") && !TailMatches("LARGE", "OBJECT"))
+	{
+		if (Matches("GRANT", MatchAnyN, "ON", MatchAny, MatchAny))
+			COMPLETE_WITH("TO");
+		else
+			COMPLETE_WITH("FROM");
+	}
 
 	/* Complete "GRANT/REVOKE * ON ALL * IN SCHEMA *" with TO/FROM */
 	else if (TailMatches("GRANT|REVOKE", MatchAny, "ON", "ALL", MatchAny, "IN", "SCHEMA", MatchAny) ||
@@ -4609,6 +4666,26 @@ match_previous_words(int pattern_id,
 			COMPLETE_WITH("FROM");
 	}
 
+	/* Complete "GRANT/REVOKE * ON LARGE OBJECT *" with TO/FROM */
+	else if (TailMatches("GRANT|REVOKE", MatchAny, "ON", "LARGE", "OBJECT", MatchAny) ||
+			 TailMatches("REVOKE", "GRANT", "OPTION", "FOR", MatchAny, "ON", "LARGE", "OBJECT", MatchAny))
+	{
+		if (TailMatches("GRANT", MatchAny, MatchAny, MatchAny, MatchAny, MatchAny))
+			COMPLETE_WITH("TO");
+		else
+			COMPLETE_WITH("FROM");
+	}
+
+	/* Complete "GRANT/REVOKE * ON LARGE OBJECTS" with TO/FROM */
+	else if (TailMatches("GRANT|REVOKE", MatchAny, "ON", "LARGE", "OBJECTS") ||
+			 TailMatches("REVOKE", "GRANT", "OPTION", "FOR", MatchAny, "ON", "LARGE", "OBJECTS"))
+	{
+		if (TailMatches("GRANT", MatchAny, MatchAny, MatchAny, MatchAny))
+			COMPLETE_WITH("TO");
+		else
+			COMPLETE_WITH("FROM");
+	}
+
 /* GROUP BY */
 	else if (TailMatches("FROM", MatchAny, "GROUP"))
 		COMPLETE_WITH("BY");
@@ -4944,7 +5021,7 @@ match_previous_words(int pattern_id,
 	/* Complete with a variable name */
 	else if (TailMatches("SET|RESET") &&
 			 !TailMatches("UPDATE", MatchAny, "SET") &&
-			 !TailMatches("ALTER", "DATABASE", MatchAny, "RESET"))
+			 !TailMatches("ALTER", "DATABASE|USER|ROLE", MatchAny, "RESET"))
 		COMPLETE_WITH_QUERY_VERBATIM_PLUS(Query_for_list_of_set_vars,
 										  "CONSTRAINTS",
 										  "TRANSACTION",
diff --git a/src/common/Makefile b/src/common/Makefile
index 1e2b91c83c4c4..2c720caa50972 100644
--- a/src/common/Makefile
+++ b/src/common/Makefile
@@ -163,7 +163,7 @@ libpgcommon_shlib.a: $(OBJS_SHLIB)
 # The JSON API normally exits on out-of-memory; disable that behavior for shared
 # library builds. This requires libpq's pqexpbuffer.h.
 jsonapi_shlib.o: override CPPFLAGS += -DJSONAPI_USE_PQEXPBUFFER
-jsonapi_shlib.o: override CPPFLAGS += -I$(libpq_srcdir)
+jsonapi_shlib.o: override CPPFLAGS := -I$(libpq_srcdir) $(CPPFLAGS)
 
 # Because this uses its own compilation rule, it doesn't use the
 # dependency tracking logic from Makefile.global.  To make sure that
diff --git a/src/common/parse_manifest.c b/src/common/parse_manifest.c
index 71973af199b90..58e0948100f4b 100644
--- a/src/common/parse_manifest.c
+++ b/src/common/parse_manifest.c
@@ -942,7 +942,7 @@ parse_xlogrecptr(XLogRecPtr *result, char *input)
 	uint32		hi;
 	uint32		lo;
 
-	if (sscanf(input, "%X/%X", &hi, &lo) != 2)
+	if (sscanf(input, "%X/%08X", &hi, &lo) != 2)
 		return false;
 	*result = ((uint64) hi) << 32 | lo;
 	return true;
diff --git a/src/fe_utils/astreamer_lz4.c b/src/fe_utils/astreamer_lz4.c
index 781aaf99f38fe..5f581d1de3769 100644
--- a/src/fe_utils/astreamer_lz4.c
+++ b/src/fe_utils/astreamer_lz4.c
@@ -322,9 +322,9 @@ astreamer_lz4_decompressor_content(astreamer *streamer,
 
 	mystreamer = (astreamer_lz4_frame *) streamer;
 	next_in = (uint8 *) data;
-	next_out = (uint8 *) mystreamer->base.bbs_buffer.data;
+	next_out = (uint8 *) mystreamer->base.bbs_buffer.data + mystreamer->bytes_written;
 	avail_in = len;
-	avail_out = mystreamer->base.bbs_buffer.maxlen;
+	avail_out = mystreamer->base.bbs_buffer.maxlen - mystreamer->bytes_written;
 
 	while (avail_in > 0)
 	{
diff --git a/src/include/access/amapi.h b/src/include/access/amapi.h
index 52916bab7a31f..70949de56ac70 100644
--- a/src/include/access/amapi.h
+++ b/src/include/access/amapi.h
@@ -293,7 +293,7 @@ typedef struct IndexAmRoutine
 	ambuild_function ambuild;
 	ambuildempty_function ambuildempty;
 	aminsert_function aminsert;
-	aminsertcleanup_function aminsertcleanup;
+	aminsertcleanup_function aminsertcleanup;	/* can be NULL */
 	ambulkdelete_function ambulkdelete;
 	amvacuumcleanup_function amvacuumcleanup;
 	amcanreturn_function amcanreturn;	/* can be NULL */
diff --git a/src/include/access/commit_ts.h b/src/include/access/commit_ts.h
index b8294e41b978e..dc39e7dd32cef 100644
--- a/src/include/access/commit_ts.h
+++ b/src/include/access/commit_ts.h
@@ -46,17 +46,6 @@ extern int	committssyncfiletag(const FileTag *ftag, char *path);
 #define COMMIT_TS_ZEROPAGE		0x00
 #define COMMIT_TS_TRUNCATE		0x10
 
-typedef struct xl_commit_ts_set
-{
-	TimestampTz timestamp;
-	RepOriginId nodeid;
-	TransactionId mainxid;
-	/* subxact Xids follow */
-}			xl_commit_ts_set;
-
-#define SizeOfCommitTsSet	(offsetof(xl_commit_ts_set, mainxid) + \
-							 sizeof(TransactionId))
-
 typedef struct xl_commit_ts_truncate
 {
 	int64		pageno;
diff --git a/src/include/access/heapam.h b/src/include/access/heapam.h
index 3a9424c19c9ae..a2bd5a897f874 100644
--- a/src/include/access/heapam.h
+++ b/src/include/access/heapam.h
@@ -21,6 +21,7 @@
 #include "access/skey.h"
 #include "access/table.h"		/* for backward compatibility */
 #include "access/tableam.h"
+#include "commands/vacuum.h"
 #include "nodes/lockoptions.h"
 #include "nodes/primnodes.h"
 #include "storage/bufpage.h"
@@ -396,9 +397,8 @@ extern void log_heap_prune_and_freeze(Relation relation, Buffer buffer,
 									  OffsetNumber *unused, int nunused);
 
 /* in heap/vacuumlazy.c */
-struct VacuumParams;
 extern void heap_vacuum_rel(Relation rel,
-							struct VacuumParams *params, BufferAccessStrategy bstrategy);
+							const VacuumParams params, BufferAccessStrategy bstrategy);
 
 /* in heap/heapam_visibility.c */
 extern bool HeapTupleSatisfiesVisibility(HeapTuple htup, Snapshot snapshot,
diff --git a/src/include/access/multixact.h b/src/include/access/multixact.h
index 4e6b0eec2ff4e..b876e98f46ed7 100644
--- a/src/include/access/multixact.h
+++ b/src/include/access/multixact.h
@@ -11,6 +11,7 @@
 #ifndef MULTIXACT_H
 #define MULTIXACT_H
 
+#include "access/transam.h"
 #include "access/xlogreader.h"
 #include "lib/stringinfo.h"
 #include "storage/sync.h"
@@ -119,7 +120,7 @@ extern int	multixactmemberssyncfiletag(const FileTag *ftag, char *path);
 
 extern void AtEOXact_MultiXact(void);
 extern void AtPrepare_MultiXact(void);
-extern void PostPrepare_MultiXact(TransactionId xid);
+extern void PostPrepare_MultiXact(FullTransactionId fxid);
 
 extern Size MultiXactShmemSize(void);
 extern void MultiXactShmemInit(void);
@@ -145,11 +146,11 @@ extern void MultiXactAdvanceNextMXact(MultiXactId minMulti,
 extern void MultiXactAdvanceOldest(MultiXactId oldestMulti, Oid oldestMultiDB);
 extern int	MultiXactMemberFreezeThreshold(void);
 
-extern void multixact_twophase_recover(TransactionId xid, uint16 info,
+extern void multixact_twophase_recover(FullTransactionId fxid, uint16 info,
 									   void *recdata, uint32 len);
-extern void multixact_twophase_postcommit(TransactionId xid, uint16 info,
+extern void multixact_twophase_postcommit(FullTransactionId fxid, uint16 info,
 										  void *recdata, uint32 len);
-extern void multixact_twophase_postabort(TransactionId xid, uint16 info,
+extern void multixact_twophase_postabort(FullTransactionId fxid, uint16 info,
 										 void *recdata, uint32 len);
 
 extern void multixact_redo(XLogReaderState *record);
diff --git a/src/include/access/slru.h b/src/include/access/slru.h
index e142800aab216..20dbd1e0070be 100644
--- a/src/include/access/slru.h
+++ b/src/include/access/slru.h
@@ -187,6 +187,7 @@ extern void SimpleLruInit(SlruCtl ctl, const char *name, int nslots, int nlsns,
 						  int bank_tranche_id, SyncRequestHandler sync_handler,
 						  bool long_segment_names);
 extern int	SimpleLruZeroPage(SlruCtl ctl, int64 pageno);
+extern void SimpleLruZeroAndWritePage(SlruCtl ctl, int64 pageno);
 extern int	SimpleLruReadPage(SlruCtl ctl, int64 pageno, bool write_ok,
 							  TransactionId xid);
 extern int	SimpleLruReadPage_ReadOnly(SlruCtl ctl, int64 pageno,
diff --git a/src/include/access/tableam.h b/src/include/access/tableam.h
index 8713e12cbfb99..1c9e802a6b128 100644
--- a/src/include/access/tableam.h
+++ b/src/include/access/tableam.h
@@ -20,6 +20,7 @@
 #include "access/relscan.h"
 #include "access/sdir.h"
 #include "access/xact.h"
+#include "commands/vacuum.h"
 #include "executor/tuptable.h"
 #include "storage/read_stream.h"
 #include "utils/rel.h"
@@ -36,7 +37,6 @@ extern PGDLLIMPORT bool synchronize_seqscans;
 struct BulkInsertStateData;
 struct IndexInfo;
 struct SampleScanState;
-struct VacuumParams;
 struct ValidateIndexState;
 
 /*
@@ -645,7 +645,7 @@ typedef struct TableAmRoutine
 	 * integrate with autovacuum's scheduling.
 	 */
 	void		(*relation_vacuum) (Relation rel,
-									struct VacuumParams *params,
+									const VacuumParams params,
 									BufferAccessStrategy bstrategy);
 
 	/*
@@ -1664,7 +1664,7 @@ table_relation_copy_for_cluster(Relation OldTable, Relation NewTable,
  * routine, even if (for ANALYZE) it is part of the same VACUUM command.
  */
 static inline void
-table_relation_vacuum(Relation rel, struct VacuumParams *params,
+table_relation_vacuum(Relation rel, const VacuumParams params,
 					  BufferAccessStrategy bstrategy)
 {
 	rel->rd_tableam->relation_vacuum(rel, params, bstrategy);
diff --git a/src/include/access/twophase.h b/src/include/access/twophase.h
index 9fa8235503375..509bdad9a5d55 100644
--- a/src/include/access/twophase.h
+++ b/src/include/access/twophase.h
@@ -36,10 +36,10 @@ extern void PostPrepare_Twophase(void);
 
 extern TransactionId TwoPhaseGetXidByVirtualXID(VirtualTransactionId vxid,
 												bool *have_more);
-extern PGPROC *TwoPhaseGetDummyProc(TransactionId xid, bool lock_held);
-extern int	TwoPhaseGetDummyProcNumber(TransactionId xid, bool lock_held);
+extern PGPROC *TwoPhaseGetDummyProc(FullTransactionId fxid, bool lock_held);
+extern int	TwoPhaseGetDummyProcNumber(FullTransactionId fxid, bool lock_held);
 
-extern GlobalTransaction MarkAsPreparing(TransactionId xid, const char *gid,
+extern GlobalTransaction MarkAsPreparing(FullTransactionId fxid, const char *gid,
 										 TimestampTz prepared_at,
 										 Oid owner, Oid databaseid);
 
@@ -56,8 +56,9 @@ extern void CheckPointTwoPhase(XLogRecPtr redo_horizon);
 
 extern void FinishPreparedTransaction(const char *gid, bool isCommit);
 
-extern void PrepareRedoAdd(char *buf, XLogRecPtr start_lsn,
-						   XLogRecPtr end_lsn, RepOriginId origin_id);
+extern void PrepareRedoAdd(FullTransactionId fxid, char *buf,
+						   XLogRecPtr start_lsn, XLogRecPtr end_lsn,
+						   RepOriginId origin_id);
 extern void PrepareRedoRemove(TransactionId xid, bool giveWarning);
 extern void restoreTwoPhaseData(void);
 extern bool LookupGXact(const char *gid, XLogRecPtr prepare_end_lsn,
diff --git a/src/include/access/twophase_rmgr.h b/src/include/access/twophase_rmgr.h
index 3ed154bb23127..8f576402e3604 100644
--- a/src/include/access/twophase_rmgr.h
+++ b/src/include/access/twophase_rmgr.h
@@ -14,7 +14,9 @@
 #ifndef TWOPHASE_RMGR_H
 #define TWOPHASE_RMGR_H
 
-typedef void (*TwoPhaseCallback) (TransactionId xid, uint16 info,
+#include "access/transam.h"
+
+typedef void (*TwoPhaseCallback) (FullTransactionId fxid, uint16 info,
 								  void *recdata, uint32 len);
 typedef uint8 TwoPhaseRmgrId;
 
diff --git a/src/include/access/xlog.h b/src/include/access/xlog.h
index d313099c027f0..d12798be3d807 100644
--- a/src/include/access/xlog.h
+++ b/src/include/access/xlog.h
@@ -139,10 +139,9 @@ extern PGDLLIMPORT bool XLOG_DEBUG;
 #define CHECKPOINT_IS_SHUTDOWN	0x0001	/* Checkpoint is for shutdown */
 #define CHECKPOINT_END_OF_RECOVERY	0x0002	/* Like shutdown checkpoint, but
 											 * issued at end of WAL recovery */
-#define CHECKPOINT_IMMEDIATE	0x0004	/* Do it without delays */
+#define CHECKPOINT_FAST			0x0004	/* Do it without delays */
 #define CHECKPOINT_FORCE		0x0008	/* Force even if no activity */
-#define CHECKPOINT_FLUSH_ALL	0x0010	/* Flush all pages, including those
-										 * belonging to unlogged tables */
+#define CHECKPOINT_FLUSH_UNLOGGED	0x0010	/* Flush unlogged tables */
 /* These are important to RequestCheckpoint */
 #define CHECKPOINT_WAIT			0x0020	/* Wait for completion */
 #define CHECKPOINT_REQUESTED	0x0040	/* Checkpoint request has been made */
diff --git a/src/include/access/xlog_internal.h b/src/include/access/xlog_internal.h
index 2cf8d55d706d1..cc06fc29ab2b2 100644
--- a/src/include/access/xlog_internal.h
+++ b/src/include/access/xlog_internal.h
@@ -316,16 +316,6 @@ typedef struct XLogRecData
 	uint32		len;			/* length of rmgr data to include */
 } XLogRecData;
 
-/*
- * Recovery target action.
- */
-typedef enum
-{
-	RECOVERY_TARGET_ACTION_PAUSE,
-	RECOVERY_TARGET_ACTION_PROMOTE,
-	RECOVERY_TARGET_ACTION_SHUTDOWN,
-}			RecoveryTargetAction;
-
 struct LogicalDecodingContext;
 struct XLogRecordBuffer;
 
diff --git a/src/include/access/xlogdefs.h b/src/include/access/xlogdefs.h
index 9e41c9f6e8446..514f03df0b69b 100644
--- a/src/include/access/xlogdefs.h
+++ b/src/include/access/xlogdefs.h
@@ -38,7 +38,10 @@ typedef uint64 XLogRecPtr;
 /*
  * Handy macro for printing XLogRecPtr in conventional format, e.g.,
  *
- * printf("%X/%X", LSN_FORMAT_ARGS(lsn));
+ * printf("%X/08X", LSN_FORMAT_ARGS(lsn));
+ *
+ * To avoid breaking translatable messages, we're directly applying the
+ * LSN format instead of using a macro.
  */
 #define LSN_FORMAT_ARGS(lsn) (AssertVariableIsOfTypeMacro((lsn), XLogRecPtr), (uint32) ((lsn) >> 32)), ((uint32) (lsn))
 
diff --git a/src/include/access/xloginsert.h b/src/include/access/xloginsert.h
index cf057f033a281..d6a71415d4fd7 100644
--- a/src/include/access/xloginsert.h
+++ b/src/include/access/xloginsert.h
@@ -44,6 +44,7 @@
 extern void XLogBeginInsert(void);
 extern void XLogSetRecordFlags(uint8 flags);
 extern XLogRecPtr XLogInsert(RmgrId rmid, uint8 info);
+extern XLogRecPtr XLogSimpleInsertInt64(RmgrId rmid, uint8 info, int64 value);
 extern void XLogEnsureRecordSpace(int max_block_id, int ndatas);
 extern void XLogRegisterData(const void *data, uint32 len);
 extern void XLogRegisterBuffer(uint8 block_id, Buffer buffer, uint8 flags);
diff --git a/src/include/access/xlogrecovery.h b/src/include/access/xlogrecovery.h
index 91446303024ae..8e475e266d18e 100644
--- a/src/include/access/xlogrecovery.h
+++ b/src/include/access/xlogrecovery.h
@@ -40,6 +40,16 @@ typedef enum
 	RECOVERY_TARGET_TIMELINE_NUMERIC,
 } RecoveryTargetTimeLineGoal;
 
+/*
+ * Recovery target action.
+ */
+typedef enum
+{
+	RECOVERY_TARGET_ACTION_PAUSE,
+	RECOVERY_TARGET_ACTION_PROMOTE,
+	RECOVERY_TARGET_ACTION_SHUTDOWN,
+}			RecoveryTargetAction;
+
 /* Recovery pause states */
 typedef enum RecoveryPauseState
 {
diff --git a/src/include/backup/basebackup_sink.h b/src/include/backup/basebackup_sink.h
index 8a5ee996a45ed..310d92b8b9d45 100644
--- a/src/include/backup/basebackup_sink.h
+++ b/src/include/backup/basebackup_sink.h
@@ -287,7 +287,8 @@ extern bbsink *bbsink_copystream_new(bool send_to_client);
 extern bbsink *bbsink_gzip_new(bbsink *next, pg_compress_specification *);
 extern bbsink *bbsink_lz4_new(bbsink *next, pg_compress_specification *);
 extern bbsink *bbsink_zstd_new(bbsink *next, pg_compress_specification *);
-extern bbsink *bbsink_progress_new(bbsink *next, bool estimate_backup_size);
+extern bbsink *bbsink_progress_new(bbsink *next, bool estimate_backup_size,
+								   bool incremental);
 extern bbsink *bbsink_server_new(bbsink *next, char *pathname);
 extern bbsink *bbsink_throttle_new(bbsink *next, uint32 maxrate);
 
diff --git a/src/include/c.h b/src/include/c.h
index 8cdc16a0f4a9b..6d4495bdd9f68 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -332,6 +332,36 @@
 #define pg_unreachable() abort()
 #endif
 
+/*
+ * pg_assume(expr) states that we assume `expr` to evaluate to true. In assert
+ * enabled builds pg_assume() is turned into an assertion, in optimized builds
+ * we try to clue the compiler into the fact that `expr` is true.
+ *
+ * This is useful for two purposes:
+ *
+ * 1) Avoid compiler warnings by telling the compiler about assumptions the
+ *	  code makes. This is particularly useful when building with optimizations
+ *	  and w/o assertions.
+ *
+ * 2) Help the compiler to generate more efficient code
+ *
+ * It is unspecified whether `expr` is evaluated, therefore it better be
+ * side-effect free.
+ */
+#if defined(USE_ASSERT_CHECKING)
+#define pg_assume(expr) Assert(expr)
+#elif defined(HAVE__BUILTIN_UNREACHABLE)
+#define pg_assume(expr) \
+	do { \
+		if (!(expr)) \
+			__builtin_unreachable(); \
+	} while (0)
+#elif defined(_MSC_VER)
+#define pg_assume(expr) __assume(expr)
+#else
+#define pg_assume(expr) ((void) 0)
+#endif
+
 /*
  * Hints to the compiler about the likelihood of a branch. Both likely() and
  * unlikely() return the boolean value of the contained expression.
@@ -376,25 +406,7 @@
  * pretty trivial: VA_ARGS_NARGS_() returns its 64th argument, and we set up
  * the call so that that is the appropriate one of the list of constants.
  * This idea is due to Laurent Deniau.
- *
- * MSVC has an implementation of __VA_ARGS__ that doesn't conform to the
- * standard unless you use the /Zc:preprocessor compiler flag, but that
- * isn't available before Visual Studio 2019.  For now, use a different
- * definition that also works on older compilers.
  */
-#ifdef _MSC_VER
-#define EXPAND(args) args
-#define VA_ARGS_NARGS(...) \
-	VA_ARGS_NARGS_ EXPAND((__VA_ARGS__, \
-				   63,62,61,60,                   \
-				   59,58,57,56,55,54,53,52,51,50, \
-				   49,48,47,46,45,44,43,42,41,40, \
-				   39,38,37,36,35,34,33,32,31,30, \
-				   29,28,27,26,25,24,23,22,21,20, \
-				   19,18,17,16,15,14,13,12,11,10, \
-				   9, 8, 7, 6, 5, 4, 3, 2, 1, 0))
-#else
-
 #define VA_ARGS_NARGS(...) \
 	VA_ARGS_NARGS_(__VA_ARGS__, \
 				   63,62,61,60,                   \
@@ -404,7 +416,6 @@
 				   29,28,27,26,25,24,23,22,21,20, \
 				   19,18,17,16,15,14,13,12,11,10, \
 				   9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
-#endif
 
 #define VA_ARGS_NARGS_( \
 	_01,_02,_03,_04,_05,_06,_07,_08,_09,_10, \
diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index 479629825f5b7..c4fe8b991af46 100644
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -57,6 +57,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	202506291
+#define CATALOG_VERSION_NO	202508051
 
 #endif
diff --git a/src/include/catalog/pg_cast.dat b/src/include/catalog/pg_cast.dat
index ab46be606f03d..fbfd669587f07 100644
--- a/src/include/catalog/pg_cast.dat
+++ b/src/include/catalog/pg_cast.dat
@@ -281,6 +281,20 @@
   castcontext => 'a', castmethod => 'f' },
 { castsource => 'regnamespace', casttarget => 'int4', castfunc => '0',
   castcontext => 'a', castmethod => 'b' },
+{ castsource => 'oid', casttarget => 'regdatabase', castfunc => '0',
+  castcontext => 'i', castmethod => 'b' },
+{ castsource => 'regdatabase', casttarget => 'oid', castfunc => '0',
+  castcontext => 'i', castmethod => 'b' },
+{ castsource => 'int8', casttarget => 'regdatabase', castfunc => 'oid',
+  castcontext => 'i', castmethod => 'f' },
+{ castsource => 'int2', casttarget => 'regdatabase', castfunc => 'int4(int2)',
+  castcontext => 'i', castmethod => 'f' },
+{ castsource => 'int4', casttarget => 'regdatabase', castfunc => '0',
+  castcontext => 'i', castmethod => 'b' },
+{ castsource => 'regdatabase', casttarget => 'int8', castfunc => 'int8(oid)',
+  castcontext => 'a', castmethod => 'f' },
+{ castsource => 'regdatabase', casttarget => 'int4', castfunc => '0',
+  castcontext => 'a', castmethod => 'b' },
 
 # String category
 { castsource => 'text', casttarget => 'bpchar', castfunc => '0',
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index fb4f7f50350ad..118d6da1ace0e 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -5688,9 +5688,9 @@
 { oid => '6231', descr => 'statistics: information about subscription stats',
   proname => 'pg_stat_get_subscription_stats', provolatile => 's',
   proparallel => 'r', prorettype => 'record', proargtypes => 'oid',
-  proallargtypes => '{oid,oid,int8,int8,int8,int8,int8,int8,int8,int8,int8,timestamptz}',
-  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o}',
-  proargnames => '{subid,subid,apply_error_count,sync_error_count,confl_insert_exists,confl_update_origin_differs,confl_update_exists,confl_update_missing,confl_delete_origin_differs,confl_delete_missing,confl_multiple_unique_conflicts,stats_reset}',
+  proallargtypes => '{oid,oid,int8,int8,int8,int8,int8,int8,int8,int8,int8,int8,timestamptz}',
+  proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o}',
+  proargnames => '{subid,subid,apply_error_count,sync_error_count,confl_insert_exists,confl_update_origin_differs,confl_update_exists,confl_update_deleted,confl_update_missing,confl_delete_origin_differs,confl_delete_missing,confl_multiple_unique_conflicts,stats_reset}',
   prosrc => 'pg_stat_get_subscription_stats' },
 { oid => '6118', descr => 'statistics: information about subscription',
   proname => 'pg_stat_get_subscription', prorows => '10', proisstrict => 'f',
@@ -7455,6 +7455,17 @@
   prorettype => 'regnamespace', proargtypes => 'text',
   prosrc => 'to_regnamespace' },
 
+{ oid => '8321', descr => 'I/O',
+  proname => 'regdatabasein', provolatile => 's', prorettype => 'regdatabase',
+  proargtypes => 'cstring', prosrc => 'regdatabasein' },
+{ oid => '8322', descr => 'I/O',
+  proname => 'regdatabaseout', provolatile => 's', prorettype => 'cstring',
+  proargtypes => 'regdatabase', prosrc => 'regdatabaseout' },
+{ oid => '8323', descr => 'convert database name to regdatabase',
+  proname => 'to_regdatabase', provolatile => 's',
+  prorettype => 'regdatabase', proargtypes => 'text',
+  prosrc => 'to_regdatabase' },
+
 { oid => '6210', descr => 'test whether string is valid input for data type',
   proname => 'pg_input_is_valid', provolatile => 's', prorettype => 'bool',
   proargtypes => 'text text', prosrc => 'pg_input_is_valid' },
@@ -8313,6 +8324,12 @@
 { oid => '4088', descr => 'I/O',
   proname => 'regnamespacesend', prorettype => 'bytea',
   proargtypes => 'regnamespace', prosrc => 'regnamespacesend' },
+{ oid => '8324', descr => 'I/O',
+  proname => 'regdatabaserecv', prorettype => 'regdatabase',
+  proargtypes => 'internal', prosrc => 'regdatabaserecv' },
+{ oid => '8325', descr => 'I/O',
+  proname => 'regdatabasesend', prorettype => 'bytea',
+  proargtypes => 'regdatabase', prosrc => 'regdatabasesend' },
 { oid => '2456', descr => 'I/O',
   proname => 'bit_recv', prorettype => 'bit',
   proargtypes => 'internal oid int4', prosrc => 'bit_recv' },
@@ -8555,6 +8572,14 @@
   proargnames => '{name,numa_node,size}',
   prosrc => 'pg_get_shmem_allocations_numa' },
 
+{ oid => '9314',
+  descr => 'shared memory allocations tracked in the DSM registry',
+  proname => 'pg_get_dsm_registry_allocations', prorows => '50',
+  proretset => 't', provolatile => 'v', prorettype => 'record',
+  proargtypes => '', proallargtypes => '{text,text,int8}',
+  proargmodes => '{o,o,o}', proargnames => '{name,type,size}',
+  prosrc => 'pg_get_dsm_registry_allocations' },
+
 # memory context of local backend
 { oid => '2282',
   descr => 'information about all memory contexts of local backend',
@@ -11776,6 +11801,10 @@
   proname => 'binary_upgrade_replorigin_advance', proisstrict => 'f',
   provolatile => 'v', proparallel => 'u', prorettype => 'void',
   proargtypes => 'text pg_lsn', prosrc => 'binary_upgrade_replorigin_advance' },
+{ oid => '9159', descr => 'for use by pg_upgrade (conflict detection slot)',
+  proname => 'binary_upgrade_create_conflict_detection_slot', proisstrict => 'f',
+  provolatile => 'v', proparallel => 'u', prorettype => 'void',
+  proargtypes => '', prosrc => 'binary_upgrade_create_conflict_detection_slot' },
 
 # conversion functions
 { oid => '4302',
diff --git a/src/include/catalog/pg_publication.h b/src/include/catalog/pg_publication.h
index 48c7d1a861527..6e074190fd2cd 100644
--- a/src/include/catalog/pg_publication.h
+++ b/src/include/catalog/pg_publication.h
@@ -146,7 +146,7 @@ extern Publication *GetPublicationByName(const char *pubname, bool missing_ok);
 extern List *GetRelationPublications(Oid relid);
 
 /*---------
- * Expected values for pub_partopt parameter of GetRelationPublications(),
+ * Expected values for pub_partopt parameter of GetPublicationRelations(),
  * which allows callers to specify which partitions of partitioned tables
  * mentioned in the publication they expect to see.
  *
diff --git a/src/include/catalog/pg_subscription.h b/src/include/catalog/pg_subscription.h
index 20fc329992dc5..231ef84ec9a6f 100644
--- a/src/include/catalog/pg_subscription.h
+++ b/src/include/catalog/pg_subscription.h
@@ -78,6 +78,9 @@ CATALOG(pg_subscription,6100,SubscriptionRelationId) BKI_SHARED_RELATION BKI_ROW
 								 * slots) in the upstream database are enabled
 								 * to be synchronized to the standbys. */
 
+	bool		subretaindeadtuples;	/* True if dead tuples useful for
+										 * conflict detection are retained */
+
 #ifdef CATALOG_VARLEN			/* variable-length fields start here */
 	/* Connection string to the publisher */
 	text		subconninfo BKI_FORCE_NOT_NULL;
@@ -131,6 +134,8 @@ typedef struct Subscription
 								 * (i.e. the main slot and the table sync
 								 * slots) in the upstream database are enabled
 								 * to be synchronized to the standbys. */
+	bool		retaindeadtuples;	/* True if dead tuples useful for conflict
+									 * detection are retained */
 	char	   *conninfo;		/* Connection string to the publisher */
 	char	   *slotname;		/* Name of the replication slot */
 	char	   *synccommit;		/* Synchronous commit setting for worker */
diff --git a/src/include/catalog/pg_subscription_rel.h b/src/include/catalog/pg_subscription_rel.h
index c91797c869c24..f458447a0e5fb 100644
--- a/src/include/catalog/pg_subscription_rel.h
+++ b/src/include/catalog/pg_subscription_rel.h
@@ -85,7 +85,7 @@ typedef struct SubscriptionRelState
 extern void AddSubscriptionRelState(Oid subid, Oid relid, char state,
 									XLogRecPtr sublsn, bool retain_lock);
 extern void UpdateSubscriptionRelState(Oid subid, Oid relid, char state,
-									   XLogRecPtr sublsn);
+									   XLogRecPtr sublsn, bool already_locked);
 extern char GetSubscriptionRelState(Oid subid, Oid relid, XLogRecPtr *sublsn);
 extern void RemoveSubscriptionRel(Oid subid, Oid relid);
 
diff --git a/src/include/catalog/pg_type.dat b/src/include/catalog/pg_type.dat
index 6dca77e0a22f7..29e4ffffc9806 100644
--- a/src/include/catalog/pg_type.dat
+++ b/src/include/catalog/pg_type.dat
@@ -399,6 +399,11 @@
   typinput => 'regnamespacein', typoutput => 'regnamespaceout',
   typreceive => 'regnamespacerecv', typsend => 'regnamespacesend',
   typalign => 'i' },
+{ oid => '8326', array_type_oid => '8327', descr => 'registered database',
+  typname => 'regdatabase', typlen => '4', typbyval => 't', typcategory => 'N',
+  typinput => 'regdatabasein', typoutput => 'regdatabaseout',
+  typreceive => 'regdatabaserecv', typsend => 'regdatabasesend',
+  typalign => 'i' },
 
 # uuid
 { oid => '2950', array_type_oid => '2951', descr => 'UUID',
diff --git a/src/include/commands/copy.h b/src/include/commands/copy.h
index 06dfdfef7210c..541176e198032 100644
--- a/src/include/commands/copy.h
+++ b/src/include/commands/copy.h
@@ -20,15 +20,12 @@
 #include "tcop/dest.h"
 
 /*
- * Represents whether a header line should be present, and whether it must
- * match the actual names (which implies "true").
+ * Represents whether a header line must match the actual names
+ * (which implies "true"), and whether it should be present.
  */
-typedef enum CopyHeaderChoice
-{
-	COPY_HEADER_FALSE = 0,
-	COPY_HEADER_TRUE,
-	COPY_HEADER_MATCH,
-} CopyHeaderChoice;
+#define COPY_HEADER_MATCH	-1
+#define COPY_HEADER_FALSE	0
+#define COPY_HEADER_TRUE	1
 
 /*
  * Represents where to save input processing errors.  More values to be added
@@ -64,7 +61,8 @@ typedef struct CopyFormatOptions
 	bool		binary;			/* binary format? */
 	bool		freeze;			/* freeze rows on loading? */
 	bool		csv_mode;		/* Comma Separated Value format? */
-	CopyHeaderChoice header_line;	/* header line? */
+	int			header_line;	/* number of lines to skip or COPY_HEADER_XXX
+								 * value (see the above) */
 	char	   *null_print;		/* NULL marker string (server encoding!) */
 	int			null_print_len; /* length of same */
 	char	   *null_print_client;	/* same converted to file encoding */
diff --git a/src/include/commands/progress.h b/src/include/commands/progress.h
index 7c736e7b03bcf..1cde4bd9bcf14 100644
--- a/src/include/commands/progress.h
+++ b/src/include/commands/progress.h
@@ -130,6 +130,7 @@
 #define PROGRESS_BASEBACKUP_BACKUP_STREAMED			2
 #define PROGRESS_BASEBACKUP_TBLSPC_TOTAL			3
 #define PROGRESS_BASEBACKUP_TBLSPC_STREAMED			4
+#define PROGRESS_BASEBACKUP_BACKUP_TYPE				5
 
 /* Phases of pg_basebackup (as advertised via PROGRESS_BASEBACKUP_PHASE) */
 #define PROGRESS_BASEBACKUP_PHASE_WAIT_CHECKPOINT		1
@@ -138,6 +139,10 @@
 #define PROGRESS_BASEBACKUP_PHASE_WAIT_WAL_ARCHIVE		4
 #define PROGRESS_BASEBACKUP_PHASE_TRANSFER_WAL			5
 
+/* Types of pg_basebackup (as advertised via PROGRESS_BASEBACKUP_BACKUP_TYPE) */
+#define PROGRESS_BASEBACKUP_BACKUP_TYPE_FULL			1
+#define PROGRESS_BASEBACKUP_BACKUP_TYPE_INCREMENTAL		2
+
 /* Progress parameters for PROGRESS_COPY */
 #define PROGRESS_COPY_BYTES_PROCESSED 0
 #define PROGRESS_COPY_BYTES_TOTAL 1
diff --git a/src/include/commands/subscriptioncmds.h b/src/include/commands/subscriptioncmds.h
index c2262e46a7f5c..9b288ad22a623 100644
--- a/src/include/commands/subscriptioncmds.h
+++ b/src/include/commands/subscriptioncmds.h
@@ -28,4 +28,9 @@ extern void AlterSubscriptionOwner_oid(Oid subid, Oid newOwnerId);
 
 extern char defGetStreamingMode(DefElem *def);
 
+extern ObjectAddress AlterSubscription(ParseState *pstate, AlterSubscriptionStmt *stmt, bool isTopLevel);
+
+extern void CheckSubDeadTupleRetention(bool check_guc, bool sub_disabled,
+									   int elevel_for_sub_disabled);
+
 #endif							/* SUBSCRIPTIONCMDS_H */
diff --git a/src/include/commands/trigger.h b/src/include/commands/trigger.h
index 2ed2c4bb3784b..cfd7daa20edac 100644
--- a/src/include/commands/trigger.h
+++ b/src/include/commands/trigger.h
@@ -213,7 +213,8 @@ extern bool ExecBRDeleteTriggers(EState *estate,
 								 HeapTuple fdw_trigtuple,
 								 TupleTableSlot **epqslot,
 								 TM_Result *tmresult,
-								 TM_FailureData *tmfd);
+								 TM_FailureData *tmfd,
+								 bool is_merge_delete);
 extern void ExecARDeleteTriggers(EState *estate,
 								 ResultRelInfo *relinfo,
 								 ItemPointer tupleid,
@@ -235,7 +236,8 @@ extern bool ExecBRUpdateTriggers(EState *estate,
 								 HeapTuple fdw_trigtuple,
 								 TupleTableSlot *newslot,
 								 TM_Result *tmresult,
-								 TM_FailureData *tmfd);
+								 TM_FailureData *tmfd,
+								 bool is_merge_update);
 extern void ExecARUpdateTriggers(EState *estate,
 								 ResultRelInfo *relinfo,
 								 ResultRelInfo *src_partinfo,
diff --git a/src/include/commands/vacuum.h b/src/include/commands/vacuum.h
index bc37a80dc74fa..14eeccbd71850 100644
--- a/src/include/commands/vacuum.h
+++ b/src/include/commands/vacuum.h
@@ -336,7 +336,7 @@ extern PGDLLIMPORT int64 parallel_vacuum_worker_delay_ns;
 
 /* in commands/vacuum.c */
 extern void ExecVacuum(ParseState *pstate, VacuumStmt *vacstmt, bool isTopLevel);
-extern void vacuum(List *relations, VacuumParams *params,
+extern void vacuum(List *relations, const VacuumParams params,
 				   BufferAccessStrategy bstrategy, MemoryContext vac_context,
 				   bool isTopLevel);
 extern void vac_open_indexes(Relation relation, LOCKMODE lockmode,
@@ -357,7 +357,7 @@ extern void vac_update_relstats(Relation relation,
 								bool *frozenxid_updated,
 								bool *minmulti_updated,
 								bool in_outer_xact);
-extern bool vacuum_get_cutoffs(Relation rel, const VacuumParams *params,
+extern bool vacuum_get_cutoffs(Relation rel, const VacuumParams params,
 							   struct VacuumCutoffs *cutoffs);
 extern bool vacuum_xid_failsafe_check(const struct VacuumCutoffs *cutoffs);
 extern void vac_update_datfrozenxid(void);
@@ -398,7 +398,7 @@ extern void parallel_vacuum_main(dsm_segment *seg, shm_toc *toc);
 
 /* in commands/analyze.c */
 extern void analyze_rel(Oid relid, RangeVar *relation,
-						VacuumParams *params, List *va_cols, bool in_outer_xact,
+						const VacuumParams params, List *va_cols, bool in_outer_xact,
 						BufferAccessStrategy bstrategy);
 extern bool std_typanalyze(VacAttrStats *stats);
 
diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h
index 104b059544dd3..a71502efeed75 100644
--- a/src/include/executor/executor.h
+++ b/src/include/executor/executor.h
@@ -14,6 +14,7 @@
 #ifndef EXECUTOR_H
 #define EXECUTOR_H
 
+#include "datatype/timestamp.h"
 #include "executor/execdesc.h"
 #include "fmgr.h"
 #include "nodes/lockoptions.h"
@@ -759,7 +760,18 @@ extern bool RelationFindReplTupleByIndex(Relation rel, Oid idxoid,
 										 TupleTableSlot *outslot);
 extern bool RelationFindReplTupleSeq(Relation rel, LockTupleMode lockmode,
 									 TupleTableSlot *searchslot, TupleTableSlot *outslot);
-
+extern bool RelationFindDeletedTupleInfoSeq(Relation rel,
+											TupleTableSlot *searchslot,
+											TransactionId oldestxmin,
+											TransactionId *delete_xid,
+											RepOriginId *delete_origin,
+											TimestampTz *delete_time);
+extern bool RelationFindDeletedTupleInfoByIndex(Relation rel, Oid idxoid,
+												TupleTableSlot *searchslot,
+												TransactionId oldestxmin,
+												TransactionId *delete_xid,
+												RepOriginId *delete_origin,
+												TimestampTz *delete_time);
 extern void ExecSimpleRelationInsert(ResultRelInfo *resultRelInfo,
 									 EState *estate, TupleTableSlot *slot);
 extern void ExecSimpleRelationUpdate(ResultRelInfo *resultRelInfo,
diff --git a/src/include/libpq/libpq-be-fe-helpers.h b/src/include/libpq/libpq-be-fe-helpers.h
index 16205b824fa55..1c4a342090c33 100644
--- a/src/include/libpq/libpq-be-fe-helpers.h
+++ b/src/include/libpq/libpq-be-fe-helpers.h
@@ -30,17 +30,7 @@
 #ifndef LIBPQ_BE_FE_HELPERS_H
 #define LIBPQ_BE_FE_HELPERS_H
 
-/*
- * Despite the name, BUILDING_DLL is set only when building code directly part
- * of the backend. Which also is where libpq isn't allowed to be
- * used. Obviously this doesn't protect against libpq-fe.h getting included
- * otherwise, but perhaps still protects against a few mistakes...
- */
-#ifdef BUILDING_DLL
-#error "libpq may not be used code directly built into the backend"
-#endif
-
-#include "libpq-fe.h"
+#include "libpq/libpq-be-fe.h"
 #include "miscadmin.h"
 #include "storage/fd.h"
 #include "storage/latch.h"
@@ -289,41 +279,30 @@ libpqsrv_exec_params(PGconn *conn,
 static inline PGresult *
 libpqsrv_get_result_last(PGconn *conn, uint32 wait_event_info)
 {
-	PGresult   *volatile lastResult = NULL;
+	PGresult   *lastResult = NULL;
 
-	/* In what follows, do not leak any PGresults on an error. */
-	PG_TRY();
+	for (;;)
 	{
-		for (;;)
-		{
-			/* Wait for, and collect, the next PGresult. */
-			PGresult   *result;
-
-			result = libpqsrv_get_result(conn, wait_event_info);
-			if (result == NULL)
-				break;			/* query is complete, or failure */
+		/* Wait for, and collect, the next PGresult. */
+		PGresult   *result;
 
-			/*
-			 * Emulate PQexec()'s behavior of returning the last result when
-			 * there are many.
-			 */
-			PQclear(lastResult);
-			lastResult = result;
+		result = libpqsrv_get_result(conn, wait_event_info);
+		if (result == NULL)
+			break;				/* query is complete, or failure */
 
-			if (PQresultStatus(lastResult) == PGRES_COPY_IN ||
-				PQresultStatus(lastResult) == PGRES_COPY_OUT ||
-				PQresultStatus(lastResult) == PGRES_COPY_BOTH ||
-				PQstatus(conn) == CONNECTION_BAD)
-				break;
-		}
-	}
-	PG_CATCH();
-	{
+		/*
+		 * Emulate PQexec()'s behavior of returning the last result when there
+		 * are many.
+		 */
 		PQclear(lastResult);
-		PG_RE_THROW();
-	}
-	PG_END_TRY();
+		lastResult = result;
 
+		if (PQresultStatus(lastResult) == PGRES_COPY_IN ||
+			PQresultStatus(lastResult) == PGRES_COPY_OUT ||
+			PQresultStatus(lastResult) == PGRES_COPY_BOTH ||
+			PQstatus(conn) == CONNECTION_BAD)
+			break;
+	}
 	return lastResult;
 }
 
@@ -454,4 +433,45 @@ exit:	;
 	return error;
 }
 
+/*
+ * libpqsrv_notice_receiver
+ *
+ * Custom notice receiver for libpq connections.
+ *
+ * This function is intended to be set via PQsetNoticeReceiver() so that
+ * NOTICE, WARNING, and similar messages from the connection are reported via
+ * ereport(), instead of being printed to stderr.
+ *
+ * Because this will be called from libpq with a "real" (not wrapped)
+ * PGresult, we need to temporarily ignore libpq-be-fe.h's wrapper macros
+ * for PGresult and also PQresultErrorMessage, and put back the wrappers
+ * afterwards.  That's not pretty, but there seems no better alternative.
+ */
+#undef PGresult
+#undef PQresultErrorMessage
+
+static inline void
+libpqsrv_notice_receiver(void *arg, const PGresult *res)
+{
+	const char *message;
+	int			len;
+	const char *prefix = (const char *) arg;
+
+	/*
+	 * Trim the trailing newline from the message text returned from
+	 * PQresultErrorMessage(), as it always includes one, to produce cleaner
+	 * log output.
+	 */
+	message = PQresultErrorMessage(res);
+	len = strlen(message);
+	if (len > 0 && message[len - 1] == '\n')
+		len--;
+
+	ereport(LOG,
+			errmsg_internal("%s: %.*s", prefix, len, message));
+}
+
+#define PGresult libpqsrv_PGresult
+#define PQresultErrorMessage libpqsrv_PQresultErrorMessage
+
 #endif							/* LIBPQ_BE_FE_HELPERS_H */
diff --git a/src/include/libpq/libpq-be-fe.h b/src/include/libpq/libpq-be-fe.h
new file mode 100644
index 0000000000000..e3f796b023092
--- /dev/null
+++ b/src/include/libpq/libpq-be-fe.h
@@ -0,0 +1,259 @@
+/*-------------------------------------------------------------------------
+ *
+ * libpq-be-fe.h
+ *	  Wrapper functions for using libpq in extensions
+ *
+ * Code built directly into the backend is not allowed to link to libpq
+ * directly. Extension code is allowed to use libpq however. One of the
+ * main risks in doing so is leaking the malloc-allocated structures
+ * returned by libpq, causing a process-lifespan memory leak.
+ *
+ * This file provides wrapper objects to help in building memory-safe code.
+ * A PGresult object wrapped this way acts much as if it were palloc'd:
+ * it will go away when the specified context is reset or deleted.
+ * We might later extend the concept to other objects such as PGconns.
+ *
+ * See also the libpq-be-fe-helpers.h file, which provides additional
+ * facilities built on top of this one.
+ *
+ * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/libpq/libpq-be-fe.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef LIBPQ_BE_FE_H
+#define LIBPQ_BE_FE_H
+
+/*
+ * Despite the name, BUILDING_DLL is set only when building code directly part
+ * of the backend. Which also is where libpq isn't allowed to be
+ * used. Obviously this doesn't protect against libpq-fe.h getting included
+ * otherwise, but perhaps still protects against a few mistakes...
+ */
+#ifdef BUILDING_DLL
+#error "libpq may not be used in code directly built into the backend"
+#endif
+
+#include "libpq-fe.h"
+
+/*
+ * Memory-context-safe wrapper object for a PGresult.
+ */
+typedef struct libpqsrv_PGresult
+{
+	PGresult   *res;			/* the wrapped PGresult */
+	MemoryContext ctx;			/* the MemoryContext it's attached to */
+	MemoryContextCallback cb;	/* the callback that implements freeing */
+} libpqsrv_PGresult;
+
+
+/*
+ * Wrap the given PGresult in a libpqsrv_PGresult object, so that it will
+ * go away automatically if the current memory context is reset or deleted.
+ *
+ * To avoid potential memory leaks, backend code must always apply this
+ * immediately to the output of any PGresult-yielding libpq function.
+ */
+static inline libpqsrv_PGresult *
+libpqsrv_PQwrap(PGresult *res)
+{
+	libpqsrv_PGresult *bres;
+	MemoryContext ctx = CurrentMemoryContext;
+
+	/* We pass through a NULL result as-is, since there's nothing to free */
+	if (res == NULL)
+		return NULL;
+	/* Attempt to allocate the wrapper ... this had better not throw error */
+	bres = (libpqsrv_PGresult *)
+		MemoryContextAllocExtended(ctx,
+								   sizeof(libpqsrv_PGresult),
+								   MCXT_ALLOC_NO_OOM);
+	/* If we failed to allocate a wrapper, free the PGresult before failing */
+	if (bres == NULL)
+	{
+		PQclear(res);
+		ereport(ERROR,
+				(errcode(ERRCODE_OUT_OF_MEMORY),
+				 errmsg("out of memory")));
+	}
+	/* Okay, set up the wrapper */
+	bres->res = res;
+	bres->ctx = ctx;
+	bres->cb.func = (MemoryContextCallbackFunction) PQclear;
+	bres->cb.arg = res;
+	MemoryContextRegisterResetCallback(ctx, &bres->cb);
+	return bres;
+}
+
+/*
+ * Free a wrapped PGresult, after detaching it from the memory context.
+ * Like PQclear(), allow the argument to be NULL.
+ */
+static inline void
+libpqsrv_PQclear(libpqsrv_PGresult *bres)
+{
+	if (bres)
+	{
+		MemoryContextUnregisterResetCallback(bres->ctx, &bres->cb);
+		PQclear(bres->res);
+		pfree(bres);
+	}
+}
+
+/*
+ * Move a wrapped PGresult to have a different parent context.
+ */
+static inline libpqsrv_PGresult *
+libpqsrv_PGresultSetParent(libpqsrv_PGresult *bres, MemoryContext ctx)
+{
+	libpqsrv_PGresult *newres;
+
+	/* We pass through a NULL result as-is */
+	if (bres == NULL)
+		return NULL;
+	/* Make a new wrapper in the target context, raising error on OOM */
+	newres = (libpqsrv_PGresult *)
+		MemoryContextAlloc(ctx, sizeof(libpqsrv_PGresult));
+	/* Okay, set up the new wrapper */
+	newres->res = bres->res;
+	newres->ctx = ctx;
+	newres->cb.func = (MemoryContextCallbackFunction) PQclear;
+	newres->cb.arg = bres->res;
+	MemoryContextRegisterResetCallback(ctx, &newres->cb);
+	/* Disarm and delete the old wrapper */
+	MemoryContextUnregisterResetCallback(bres->ctx, &bres->cb);
+	pfree(bres);
+	return newres;
+}
+
+/*
+ * Convenience wrapper for PQgetResult.
+ *
+ * We could supply wrappers for other PGresult-returning functions too,
+ * but at present there's no need.
+ */
+static inline libpqsrv_PGresult *
+libpqsrv_PQgetResult(PGconn *conn)
+{
+	return libpqsrv_PQwrap(PQgetResult(conn));
+}
+
+/*
+ * Accessor functions for libpqsrv_PGresult.  While it's not necessary to use
+ * these, they emulate the behavior of the underlying libpq functions when
+ * passed a NULL pointer.  This is particularly important for PQresultStatus,
+ * which is often the first check on a result.
+ */
+
+static inline ExecStatusType
+libpqsrv_PQresultStatus(const libpqsrv_PGresult *res)
+{
+	if (!res)
+		return PGRES_FATAL_ERROR;
+	return PQresultStatus(res->res);
+}
+
+static inline const char *
+libpqsrv_PQresultErrorMessage(const libpqsrv_PGresult *res)
+{
+	if (!res)
+		return "";
+	return PQresultErrorMessage(res->res);
+}
+
+static inline char *
+libpqsrv_PQresultErrorField(const libpqsrv_PGresult *res, int fieldcode)
+{
+	if (!res)
+		return NULL;
+	return PQresultErrorField(res->res, fieldcode);
+}
+
+static inline char *
+libpqsrv_PQcmdStatus(const libpqsrv_PGresult *res)
+{
+	if (!res)
+		return NULL;
+	return PQcmdStatus(res->res);
+}
+
+static inline int
+libpqsrv_PQntuples(const libpqsrv_PGresult *res)
+{
+	if (!res)
+		return 0;
+	return PQntuples(res->res);
+}
+
+static inline int
+libpqsrv_PQnfields(const libpqsrv_PGresult *res)
+{
+	if (!res)
+		return 0;
+	return PQnfields(res->res);
+}
+
+static inline char *
+libpqsrv_PQgetvalue(const libpqsrv_PGresult *res, int tup_num, int field_num)
+{
+	if (!res)
+		return NULL;
+	return PQgetvalue(res->res, tup_num, field_num);
+}
+
+static inline int
+libpqsrv_PQgetlength(const libpqsrv_PGresult *res, int tup_num, int field_num)
+{
+	if (!res)
+		return 0;
+	return PQgetlength(res->res, tup_num, field_num);
+}
+
+static inline int
+libpqsrv_PQgetisnull(const libpqsrv_PGresult *res, int tup_num, int field_num)
+{
+	if (!res)
+		return 1;				/* pretend it is null */
+	return PQgetisnull(res->res, tup_num, field_num);
+}
+
+static inline char *
+libpqsrv_PQfname(const libpqsrv_PGresult *res, int field_num)
+{
+	if (!res)
+		return NULL;
+	return PQfname(res->res, field_num);
+}
+
+static inline const char *
+libpqsrv_PQcmdTuples(const libpqsrv_PGresult *res)
+{
+	if (!res)
+		return "";
+	return PQcmdTuples(res->res);
+}
+
+/*
+ * Redefine these libpq entry point names concerned with PGresults so that
+ * they will operate on libpqsrv_PGresults instead.  This avoids needing to
+ * convert a lot of pre-existing code, and reduces the notational differences
+ * between frontend and backend libpq-using code.
+ */
+#define PGresult libpqsrv_PGresult
+#define PQclear libpqsrv_PQclear
+#define PQgetResult libpqsrv_PQgetResult
+#define PQresultStatus libpqsrv_PQresultStatus
+#define PQresultErrorMessage libpqsrv_PQresultErrorMessage
+#define PQresultErrorField libpqsrv_PQresultErrorField
+#define PQcmdStatus libpqsrv_PQcmdStatus
+#define PQntuples libpqsrv_PQntuples
+#define PQnfields libpqsrv_PQnfields
+#define PQgetvalue libpqsrv_PQgetvalue
+#define PQgetlength libpqsrv_PQgetlength
+#define PQgetisnull libpqsrv_PQgetisnull
+#define PQfname libpqsrv_PQfname
+#define PQcmdTuples libpqsrv_PQcmdTuples
+
+#endif							/* LIBPQ_BE_FE_H */
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index 2492282213ff3..e107d6e5f8174 100644
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -157,34 +157,6 @@ typedef struct ExprState
  *		entries for a particular index.  Used for both index_build and
  *		retail creation of index entries.
  *
- *		NumIndexAttrs		total number of columns in this index
- *		NumIndexKeyAttrs	number of key columns in index
- *		IndexAttrNumbers	underlying-rel attribute numbers used as keys
- *							(zeroes indicate expressions). It also contains
- * 							info about included columns.
- *		Expressions			expr trees for expression entries, or NIL if none
- *		ExpressionsState	exec state for expressions, or NIL if none
- *		Predicate			partial-index predicate, or NIL if none
- *		PredicateState		exec state for predicate, or NIL if none
- *		ExclusionOps		Per-column exclusion operators, or NULL if none
- *		ExclusionProcs		Underlying function OIDs for ExclusionOps
- *		ExclusionStrats		Opclass strategy numbers for ExclusionOps
- *		UniqueOps			These are like Exclusion*, but for unique indexes
- *		UniqueProcs
- *		UniqueStrats
- *		Unique				is it a unique index?
- *		OpclassOptions		opclass-specific options, or NULL if none
- *		ReadyForInserts		is it valid for inserts?
- *		CheckedUnchanged	IndexUnchanged status determined yet?
- *		IndexUnchanged		aminsert hint, cached for retail inserts
- *		Concurrent			are we doing a concurrent index build?
- *		BrokenHotChain		did we detect any broken HOT chains?
- *		Summarizing			is it a summarizing index?
- *		ParallelWorkers		# of workers requested (excludes leader)
- *		Am					Oid of index AM
- *		AmCache				private cache area for index AM
- *		Context				memory context holding this IndexInfo
- *
  * ii_Concurrent, ii_BrokenHotChain, and ii_ParallelWorkers are used only
  * during index build; they're conventionally zeroed otherwise.
  * ----------------
@@ -192,31 +164,67 @@ typedef struct ExprState
 typedef struct IndexInfo
 {
 	NodeTag		type;
-	int			ii_NumIndexAttrs;	/* total number of columns in index */
-	int			ii_NumIndexKeyAttrs;	/* number of key columns in index */
+
+	/* total number of columns in index */
+	int			ii_NumIndexAttrs;
+	/* number of key columns in index */
+	int			ii_NumIndexKeyAttrs;
+
+	/*
+	 * Underlying-rel attribute numbers used as keys (zeroes indicate
+	 * expressions). It also contains info about included columns.
+	 */
 	AttrNumber	ii_IndexAttrNumbers[INDEX_MAX_KEYS];
+
+	/* expr trees for expression entries, or NIL if none */
 	List	   *ii_Expressions; /* list of Expr */
+	/* exec state for expressions, or NIL if none */
 	List	   *ii_ExpressionsState;	/* list of ExprState */
+
+	/* partial-index predicate, or NIL if none */
 	List	   *ii_Predicate;	/* list of Expr */
+	/* exec state for expressions, or NIL if none */
 	ExprState  *ii_PredicateState;
+
+	/* Per-column exclusion operators, or NULL if none */
 	Oid		   *ii_ExclusionOps;	/* array with one entry per column */
+	/* Underlying function OIDs for ExclusionOps */
 	Oid		   *ii_ExclusionProcs;	/* array with one entry per column */
+	/* Opclass strategy numbers for ExclusionOps */
 	uint16	   *ii_ExclusionStrats; /* array with one entry per column */
+
+	/* These are like Exclusion*, but for unique indexes */
 	Oid		   *ii_UniqueOps;	/* array with one entry per column */
 	Oid		   *ii_UniqueProcs; /* array with one entry per column */
 	uint16	   *ii_UniqueStrats;	/* array with one entry per column */
+
+	/* is it a unique index? */
 	bool		ii_Unique;
+	/* is NULLS NOT DISTINCT? */
 	bool		ii_NullsNotDistinct;
+	/* is it valid for inserts? */
 	bool		ii_ReadyForInserts;
+	/* IndexUnchanged status determined yet? */
 	bool		ii_CheckedUnchanged;
+	/* aminsert hint, cached for retail inserts */
 	bool		ii_IndexUnchanged;
+	/* are we doing a concurrent index build? */
 	bool		ii_Concurrent;
+	/* did we detect any broken HOT chains? */
 	bool		ii_BrokenHotChain;
+	/* is it a summarizing index? */
 	bool		ii_Summarizing;
+	/* is it a WITHOUT OVERLAPS index? */
 	bool		ii_WithoutOverlaps;
+	/* # of workers requested (excludes leader) */
 	int			ii_ParallelWorkers;
+
+	/* Oid of index AM */
 	Oid			ii_Am;
+	/* private cache area for index AM */
 	void	   *ii_AmCache;
+
+	/* memory context holding this IndexInfo */
 	MemoryContext ii_Context;
 } IndexInfo;
 
diff --git a/src/include/nodes/meson.build b/src/include/nodes/meson.build
index d1ca24dd32f0b..ea36cb0fda40c 100644
--- a/src/include/nodes/meson.build
+++ b/src/include/nodes/meson.build
@@ -28,7 +28,7 @@ node_support_input_i = [
 
 node_support_input = []
 foreach i : node_support_input_i
-  node_support_input += meson.source_root() / 'src' / 'include' / i
+  node_support_input += meson.project_source_root() / 'src' / 'include' / i
 endforeach
 
 node_support_output = [
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index ba12678d1cbd1..86a236bd58b1a 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -2536,17 +2536,20 @@ typedef struct AlterCollationStmt
  * this command.
  * ----------------------
  */
+typedef enum AlterDomainType
+{
+	AD_AlterDefault = 'T',		/* SET|DROP DEFAULT */
+	AD_DropNotNull = 'N',		/* DROP NOT NULL */
+	AD_SetNotNull = 'O',		/* SET NOT NULL */
+	AD_AddConstraint = 'C',		/* ADD CONSTRAINT */
+	AD_DropConstraint = 'X',	/* DROP CONSTRAINT */
+	AD_ValidateConstraint = 'V',	/* VALIDATE CONSTRAINT */
+} AlterDomainType;
+
 typedef struct AlterDomainStmt
 {
 	NodeTag		type;
-	char		subtype;		/*------------
-								 *	T = alter column default
-								 *	N = alter column drop not null
-								 *	O = alter column set not null
-								 *	C = add constraint
-								 *	X = drop constraint
-								 *------------
-								 */
+	AlterDomainType subtype;	/* subtype of command */
 	List	   *typeName;		/* domain to work on */
 	char	   *name;			/* column or constraint name to act on */
 	Node	   *def;			/* definition of default or constraint */
@@ -3422,15 +3425,44 @@ typedef enum FetchDirection
 	FETCH_RELATIVE,
 } FetchDirection;
 
+typedef enum FetchDirectionKeywords
+{
+	FETCH_KEYWORD_NONE = 0,
+	FETCH_KEYWORD_NEXT,
+	FETCH_KEYWORD_PRIOR,
+	FETCH_KEYWORD_FIRST,
+	FETCH_KEYWORD_LAST,
+	FETCH_KEYWORD_ABSOLUTE,
+	FETCH_KEYWORD_RELATIVE,
+	FETCH_KEYWORD_ALL,
+	FETCH_KEYWORD_FORWARD,
+	FETCH_KEYWORD_FORWARD_ALL,
+	FETCH_KEYWORD_BACKWARD,
+	FETCH_KEYWORD_BACKWARD_ALL,
+} FetchDirectionKeywords;
+
 #define FETCH_ALL	LONG_MAX
 
 typedef struct FetchStmt
 {
 	NodeTag		type;
 	FetchDirection direction;	/* see above */
-	long		howMany;		/* number of rows, or position argument */
-	char	   *portalname;		/* name of portal (cursor) */
-	bool		ismove;			/* true if MOVE */
+	/* number of rows, or position argument */
+	long		howMany pg_node_attr(query_jumble_ignore);
+	/* name of portal (cursor) */
+	char	   *portalname;
+	/* true if MOVE */
+	bool		ismove;
+
+	/*
+	 * Set when a direction_keyword (e.g., FETCH FORWARD) is used, to
+	 * distinguish it from a numeric variant (e.g., FETCH 1) for the purpose
+	 * of query jumbling.
+	 */
+	FetchDirectionKeywords direction_keyword;
+
+	/* token location, or -1 if unknown */
+	ParseLoc	location pg_node_attr(query_jumble_location);
 } FetchStmt;
 
 /* ----------------------
@@ -4015,6 +4047,7 @@ typedef struct RefreshMatViewStmt
 typedef struct CheckPointStmt
 {
 	NodeTag		type;
+	List	   *options;		/* list of DefElem nodes */
 } CheckPointStmt;
 
 /* ----------------------
diff --git a/src/include/nodes/pathnodes.h b/src/include/nodes/pathnodes.h
index 6567759595daa..ad2726f026f7d 100644
--- a/src/include/nodes/pathnodes.h
+++ b/src/include/nodes/pathnodes.h
@@ -179,6 +179,9 @@ typedef struct PlannerGlobal
 
 	/* partition descriptors */
 	PartitionDirectory partition_directory pg_node_attr(read_write_ignore);
+
+	/* hash table for NOT NULL attnums of relations */
+	struct HTAB *rel_notnullatts_hash pg_node_attr(read_write_ignore);
 } PlannerGlobal;
 
 /* macro for fetching the Plan associated with a SubPlan node */
@@ -719,6 +722,9 @@ typedef struct PartitionSchemeData *PartitionScheme;
  *				the attribute is needed as part of final targetlist
  *		attr_widths - cache space for per-attribute width estimates;
  *					  zero means not computed yet
+ *		notnullattnums - zero-based set containing attnums of NOT NULL
+ *						 columns (not populated for rels corresponding to
+ *						 non-partitioned inh==true RTEs)
  *		nulling_relids - relids of outer joins that can null this rel
  *		lateral_vars - lateral cross-references of rel, if any (list of
  *					   Vars and PlaceHolderVars)
@@ -952,11 +958,7 @@ typedef struct RelOptInfo
 	Relids	   *attr_needed pg_node_attr(read_write_ignore);
 	/* array indexed [min_attr .. max_attr] */
 	int32	   *attr_widths pg_node_attr(read_write_ignore);
-
-	/*
-	 * Zero-based set containing attnums of NOT NULL columns.  Not populated
-	 * for rels corresponding to non-partitioned inh==true RTEs.
-	 */
+	/* zero-based set containing attnums of NOT NULL columns */
 	Bitmapset  *notnullattnums;
 	/* relids of outer joins that can null this baserel */
 	Relids		nulling_relids;
@@ -2131,10 +2133,12 @@ typedef struct MemoizePath
 								 * complete after caching the first record. */
 	bool		binary_mode;	/* true when cache key should be compared bit
 								 * by bit, false when using hash equality ops */
-	Cardinality calls;			/* expected number of rescans */
 	uint32		est_entries;	/* The maximum number of entries that the
 								 * planner expects will fit in the cache, or 0
 								 * if unknown */
+	Cardinality est_calls;		/* expected number of rescans */
+	Cardinality est_unique_keys;	/* estimated unique keys, for EXPLAIN */
+	double		est_hit_ratio;	/* estimated cache hit ratio, for EXPLAIN */
 } MemoizePath;
 
 /*
diff --git a/src/include/nodes/plannodes.h b/src/include/nodes/plannodes.h
index 4f59e30d62d5e..29d7732d6a031 100644
--- a/src/include/nodes/plannodes.h
+++ b/src/include/nodes/plannodes.h
@@ -28,6 +28,21 @@
  * ----------------------------------------------------------------
  */
 
+/* ----------------
+ *		PlannedStmtOrigin
+ *
+ * PlannedStmtOrigin identifies from where a PlannedStmt comes from.
+ * ----------------
+ */
+typedef enum PlannedStmtOrigin
+{
+	PLAN_STMT_UNKNOWN = 0,		/* plan origin is not yet known */
+	PLAN_STMT_INTERNAL,			/* generated internally by a query */
+	PLAN_STMT_STANDARD,			/* standard planned statement */
+	PLAN_STMT_CACHE_GENERIC,	/* Generic cached plan */
+	PLAN_STMT_CACHE_CUSTOM,		/* Custom cached plan */
+} PlannedStmtOrigin;
+
 /* ----------------
  *		PlannedStmt node
  *
@@ -58,6 +73,9 @@ typedef struct PlannedStmt
 	/* plan identifier (can be set by plugins) */
 	int64		planId;
 
+	/* origin of plan */
+	PlannedStmtOrigin planOrigin;
+
 	/* is it insert|update|delete|merge RETURNING? */
 	bool		hasReturning;
 
@@ -1056,6 +1074,16 @@ typedef struct Memoize
 
 	/* paramids from param_exprs */
 	Bitmapset  *keyparamids;
+
+	/* Estimated number of rescans, for EXPLAIN */
+	Cardinality est_calls;
+
+	/* Estimated number of distinct lookup keys, for EXPLAIN */
+	Cardinality est_unique_keys;
+
+	/* Estimated cache hit ratio, for EXPLAIN */
+	double		est_hit_ratio;
+
 } Memoize;
 
 /* ----------------
diff --git a/src/include/optimizer/cost.h b/src/include/optimizer/cost.h
index d397fe27dc1e1..b523bcda8f3d0 100644
--- a/src/include/optimizer/cost.h
+++ b/src/include/optimizer/cost.h
@@ -118,7 +118,7 @@ extern void cost_incremental_sort(Path *path,
 								  Cost input_startup_cost, Cost input_total_cost,
 								  double input_tuples, int width, Cost comparison_cost, int sort_mem,
 								  double limit_tuples);
-extern void cost_append(AppendPath *apath);
+extern void cost_append(AppendPath *apath, PlannerInfo *root);
 extern void cost_merge_append(Path *path, PlannerInfo *root,
 							  List *pathkeys, int n_streams,
 							  int input_disabled_nodes,
diff --git a/src/include/optimizer/optimizer.h b/src/include/optimizer/optimizer.h
index 546828b54bd27..37bc13c2cbde6 100644
--- a/src/include/optimizer/optimizer.h
+++ b/src/include/optimizer/optimizer.h
@@ -154,6 +154,8 @@ extern Node *estimate_expression_value(PlannerInfo *root, Node *node);
 extern Expr *evaluate_expr(Expr *expr, Oid result_type, int32 result_typmod,
 						   Oid result_collation);
 
+extern bool var_is_nonnullable(PlannerInfo *root, Var *var, bool use_rel_info);
+
 extern List *expand_function_arguments(List *args, bool include_out_arguments,
 									   Oid result_type,
 									   struct HeapTupleData *func_tuple);
diff --git a/src/include/optimizer/pathnode.h b/src/include/optimizer/pathnode.h
index 60dcdb77e41be..58936e963cb6b 100644
--- a/src/include/optimizer/pathnode.h
+++ b/src/include/optimizer/pathnode.h
@@ -90,7 +90,7 @@ extern MemoizePath *create_memoize_path(PlannerInfo *root,
 										List *hash_operators,
 										bool singlerow,
 										bool binary_mode,
-										double calls);
+										Cardinality est_calls);
 extern UniquePath *create_unique_path(PlannerInfo *root, RelOptInfo *rel,
 									  Path *subpath, SpecialJoinInfo *sjinfo);
 extern GatherPath *create_gather_path(PlannerInfo *root,
diff --git a/src/include/optimizer/plancat.h b/src/include/optimizer/plancat.h
index cd74e4b1e8b36..d6f6f4ad2d788 100644
--- a/src/include/optimizer/plancat.h
+++ b/src/include/optimizer/plancat.h
@@ -28,6 +28,10 @@ extern PGDLLIMPORT get_relation_info_hook_type get_relation_info_hook;
 extern void get_relation_info(PlannerInfo *root, Oid relationObjectId,
 							  bool inhparent, RelOptInfo *rel);
 
+extern void get_relation_notnullatts(PlannerInfo *root, Relation relation);
+
+extern Relids find_relation_notnullatts(PlannerInfo *root, Oid relid);
+
 extern List *infer_arbiter_indexes(PlannerInfo *root);
 
 extern void estimate_rel_size(Relation rel, int32 *attr_widths,
diff --git a/src/include/optimizer/prep.h b/src/include/optimizer/prep.h
index df56202777c7f..4fbecdb446272 100644
--- a/src/include/optimizer/prep.h
+++ b/src/include/optimizer/prep.h
@@ -22,10 +22,10 @@
  * prototypes for prepjointree.c
  */
 extern void transform_MERGE_to_join(Query *parse);
+extern Query *preprocess_relation_rtes(PlannerInfo *root);
 extern void replace_empty_jointree(Query *parse);
 extern void pull_up_sublinks(PlannerInfo *root);
 extern void preprocess_function_rtes(PlannerInfo *root);
-extern Query *expand_virtual_generated_columns(PlannerInfo *root);
 extern void pull_up_subqueries(PlannerInfo *root);
 extern void flatten_simple_union_all(PlannerInfo *root);
 extern void reduce_outer_joins(PlannerInfo *root);
diff --git a/src/include/pch/meson.build b/src/include/pch/meson.build
index f6babee6f6d88..603add1a351e9 100644
--- a/src/include/pch/meson.build
+++ b/src/include/pch/meson.build
@@ -1,6 +1,6 @@
 # Copyright (c) 2022-2025, PostgreSQL Global Development Group
 
 # See https://github.com/mesonbuild/meson/issues/10338
-pch_c_h = meson.source_root() / meson.current_source_dir() / 'c_pch.h'
-pch_postgres_h = meson.source_root() / meson.current_source_dir() / 'postgres_pch.h'
-pch_postgres_fe_h = meson.source_root() / meson.current_source_dir() / 'postgres_fe_pch.h'
+pch_c_h = meson.project_source_root() / meson.current_source_dir() / 'c_pch.h'
+pch_postgres_h = meson.project_source_root() / meson.current_source_dir() / 'postgres_pch.h'
+pch_postgres_fe_h = meson.project_source_root() / meson.current_source_dir() / 'postgres_fe_pch.h'
diff --git a/src/include/pg_config.h.in b/src/include/pg_config.h.in
index 726a7c1be1f4d..c4dc5d72bdb78 100644
--- a/src/include/pg_config.h.in
+++ b/src/include/pg_config.h.in
@@ -229,6 +229,9 @@
 /* Define to 1 if you have the global variable 'int timezone'. */
 #undef HAVE_INT_TIMEZONE
 
+/* Define to 1 if you have the `io_uring_queue_init_mem' function. */
+#undef HAVE_IO_URING_QUEUE_INIT_MEM
+
 /* Define to 1 if __builtin_constant_p(x) implies "i"(x) acceptance. */
 #undef HAVE_I_CONSTRAINT__BUILTIN_CONSTANT_P
 
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index 378f2f2c2ba24..202bd2d5acedc 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -718,9 +718,9 @@ extern void pgstat_count_heap_delete(Relation rel);
 extern void pgstat_count_truncate(Relation rel);
 extern void pgstat_update_heap_dead_tuples(Relation rel, int delta);
 
-extern void pgstat_twophase_postcommit(TransactionId xid, uint16 info,
+extern void pgstat_twophase_postcommit(FullTransactionId fxid, uint16 info,
 									   void *recdata, uint32 len);
-extern void pgstat_twophase_postabort(TransactionId xid, uint16 info,
+extern void pgstat_twophase_postabort(FullTransactionId fxid, uint16 info,
 									  void *recdata, uint32 len);
 
 extern PgStat_StatTabEntry *pgstat_fetch_stat_tabentry(Oid relid);
diff --git a/src/include/port/pg_crc32c.h b/src/include/port/pg_crc32c.h
index 82313bb7fcfee..ae008118ea818 100644
--- a/src/include/port/pg_crc32c.h
+++ b/src/include/port/pg_crc32c.h
@@ -72,7 +72,7 @@ pg_comp_crc32c_dispatch(pg_crc32c crc, const void *data, size_t len)
 {
 	if (__builtin_constant_p(len) && len < 32)
 	{
-		const unsigned char *p = data;
+		const unsigned char *p = (const unsigned char *) data;
 
 		/*
 		 * For small constant inputs, inline the computation to avoid a
diff --git a/src/include/port/pg_iovec.h b/src/include/port/pg_iovec.h
index df40c7208be48..90be3af449d6f 100644
--- a/src/include/port/pg_iovec.h
+++ b/src/include/port/pg_iovec.h
@@ -21,9 +21,6 @@
 
 #else
 
-/* POSIX requires at least 16 as a maximum iovcnt. */
-#define IOV_MAX 16
-
 /* Define our own POSIX-compatible iovec struct. */
 struct iovec
 {
@@ -33,6 +30,15 @@ struct iovec
 
 #endif
 
+/*
+ * If <limits.h> didn't define IOV_MAX, define our own.  X/Open requires at
+ * least 16.  (GNU Hurd apparently feel that they're not bound by X/Open,
+ * because they don't define this symbol at all.)
+ */
+#ifndef IOV_MAX
+#define IOV_MAX 16
+#endif
+
 /*
  * Define a reasonable maximum that is safe to use on the stack in arrays of
  * struct iovec and other small types.  The operating system could limit us to
diff --git a/src/include/port/pg_numa.h b/src/include/port/pg_numa.h
index 40f1d324dcfe2..9d1ea6d0db89a 100644
--- a/src/include/port/pg_numa.h
+++ b/src/include/port/pg_numa.h
@@ -24,12 +24,17 @@ extern PGDLLIMPORT int pg_numa_get_max_node(void);
  * This is required on Linux, before pg_numa_query_pages() as we
  * need to page-fault before move_pages(2) syscall returns valid results.
  */
-#define pg_numa_touch_mem_if_required(ro_volatile_var, ptr) \
-	ro_volatile_var = *(volatile uint64 *) ptr
+static inline void
+pg_numa_touch_mem_if_required(void *ptr)
+{
+	volatile uint64 touch pg_attribute_unused();
+
+	touch = *(volatile uint64 *) ptr;
+}
 
 #else
 
-#define pg_numa_touch_mem_if_required(ro_volatile_var, ptr) \
+#define pg_numa_touch_mem_if_required(ptr) \
 	do {} while(0)
 
 #endif
diff --git a/src/include/port/solaris.h b/src/include/port/solaris.h
index e63a3bd824d6d..8ff40007c7f6a 100644
--- a/src/include/port/solaris.h
+++ b/src/include/port/solaris.h
@@ -24,3 +24,12 @@
 #if defined(__i386__)
 #include <sys/isa_defs.h>
 #endif
+
+/*
+ * On original Solaris, PAM conversation procs lack a "const" in their
+ * declaration; but recent OpenIndiana versions put it there by default.
+ * The least messy way to deal with this is to define _PAM_LEGACY_NONCONST,
+ * which causes OpenIndiana to declare pam_conv per the Solaris tradition,
+ * and also use that symbol to control omitting the "const" in our own code.
+ */
+#define _PAM_LEGACY_NONCONST 1
diff --git a/src/include/postmaster/bgwriter.h b/src/include/postmaster/bgwriter.h
index 800ecbfd13b31..97001f4e7f622 100644
--- a/src/include/postmaster/bgwriter.h
+++ b/src/include/postmaster/bgwriter.h
@@ -15,6 +15,7 @@
 #ifndef _BGWRITER_H
 #define _BGWRITER_H
 
+#include "parser/parse_node.h"
 #include "storage/block.h"
 #include "storage/relfilelocator.h"
 #include "storage/smgr.h"
@@ -30,6 +31,7 @@ extern PGDLLIMPORT double CheckPointCompletionTarget;
 pg_noreturn extern void BackgroundWriterMain(const void *startup_data, size_t startup_data_len);
 pg_noreturn extern void CheckpointerMain(const void *startup_data, size_t startup_data_len);
 
+extern void ExecCheckpoint(ParseState *pstate, CheckPointStmt *stmt);
 extern void RequestCheckpoint(int flags);
 extern void CheckpointWriteDelay(int flags, double progress);
 
diff --git a/src/include/replication/conflict.h b/src/include/replication/conflict.h
index 6c59125f25657..ff3cb8416ecff 100644
--- a/src/include/replication/conflict.h
+++ b/src/include/replication/conflict.h
@@ -32,6 +32,9 @@ typedef enum
 	/* The updated row value violates unique constraint */
 	CT_UPDATE_EXISTS,
 
+	/* The row to be updated was concurrently deleted by a different origin */
+	CT_UPDATE_DELETED,
+
 	/* The row to be updated is missing */
 	CT_UPDATE_MISSING,
 
diff --git a/src/include/replication/logicallauncher.h b/src/include/replication/logicallauncher.h
index 82b202f330515..b29453e8e4f69 100644
--- a/src/include/replication/logicallauncher.h
+++ b/src/include/replication/logicallauncher.h
@@ -25,8 +25,11 @@ extern void ApplyLauncherShmemInit(void);
 extern void ApplyLauncherForgetWorkerStartTime(Oid subid);
 
 extern void ApplyLauncherWakeupAtCommit(void);
+extern void ApplyLauncherWakeup(void);
 extern void AtEOXact_ApplyLauncher(bool isCommit);
 
+extern void CreateConflictDetectionSlot(void);
+
 extern bool IsLogicalLauncher(void);
 
 extern pid_t GetLeaderApplyWorkerPid(pid_t pid);
diff --git a/src/include/replication/slot.h b/src/include/replication/slot.h
index ffacba9d2ae52..e8fc342d1a96e 100644
--- a/src/include/replication/slot.h
+++ b/src/include/replication/slot.h
@@ -20,6 +20,13 @@
 /* directory to store replication slot data in */
 #define PG_REPLSLOT_DIR     "pg_replslot"
 
+/*
+ * The reserved name for a replication slot used to retain dead tuples for
+ * conflict detection in logical replication. See
+ * maybe_advance_nonremovable_xid() for detail.
+ */
+#define CONFLICT_DETECTION_SLOT "pg_conflict_detection"
+
 /*
  * Behaviour of replication slots, upon release or crash.
  *
@@ -220,6 +227,25 @@ typedef struct ReplicationSlot
 	 * Latest restart_lsn that has been flushed to disk. For persistent slots
 	 * the flushed LSN should be taken into account when calculating the
 	 * oldest LSN for WAL segments removal.
+	 *
+	 * Do not assume that restart_lsn will always move forward, i.e., that the
+	 * previously flushed restart_lsn is always behind data.restart_lsn. In
+	 * streaming replication using a physical slot, the restart_lsn is updated
+	 * based on the flushed WAL position reported by the walreceiver.
+	 *
+	 * This replication mode allows duplicate WAL records to be received and
+	 * overwritten. If the walreceiver receives older WAL records and then
+	 * reports them as flushed to the walsender, the restart_lsn may appear to
+	 * move backward.
+	 *
+	 * This typically occurs at the beginning of replication. One reason is
+	 * that streaming replication starts at the beginning of a segment, so, if
+	 * restart_lsn is in the middle of a segment, it will be updated to an
+	 * earlier LSN, see RequestXLogStreaming. Another reason is that the
+	 * walreceiver chooses its startpoint based on the replayed LSN, so, if
+	 * some records have been received but not yet applied, they will be
+	 * received again and leads to updating the restart_lsn to an earlier
+	 * position.
 	 */
 	XLogRecPtr	last_saved_restart_lsn;
 
@@ -266,7 +292,7 @@ extern PGDLLIMPORT ReplicationSlot *MyReplicationSlot;
 /* GUCs */
 extern PGDLLIMPORT int max_replication_slots;
 extern PGDLLIMPORT char *synchronized_standby_slots;
-extern PGDLLIMPORT int idle_replication_slot_timeout_mins;
+extern PGDLLIMPORT int idle_replication_slot_timeout_secs;
 
 /* shmem initialization functions */
 extern Size ReplicationSlotsShmemSize(void);
@@ -292,7 +318,9 @@ extern void ReplicationSlotMarkDirty(void);
 
 /* misc stuff */
 extern void ReplicationSlotInitialize(void);
-extern bool ReplicationSlotValidateName(const char *name, int elevel);
+extern bool ReplicationSlotValidateName(const char *name,
+										bool allow_reserved_name,
+										int elevel);
 extern void ReplicationSlotReserveWal(void);
 extern void ReplicationSlotsComputeRequiredXmin(bool already_locked);
 extern void ReplicationSlotsComputeRequiredLSN(void);
diff --git a/src/include/replication/worker_internal.h b/src/include/replication/worker_internal.h
index 30b2775952c38..7c0204dd6f4ce 100644
--- a/src/include/replication/worker_internal.h
+++ b/src/include/replication/worker_internal.h
@@ -86,6 +86,17 @@ typedef struct LogicalRepWorker
 	/* Indicates whether apply can be performed in parallel. */
 	bool		parallel_apply;
 
+	/*
+	 * Changes made by this transaction and subsequent ones must be preserved.
+	 * This ensures that update_deleted conflicts can be accurately detected
+	 * during the apply phase of logical replication by this worker.
+	 *
+	 * The logical replication launcher manages an internal replication slot
+	 * named "pg_conflict_detection". It asynchronously collects this ID to
+	 * decide when to advance the xmin value of the slot.
+	 */
+	TransactionId oldest_nonremovable_xid;
+
 	/* Stats. */
 	XLogRecPtr	last_lsn;
 	TimestampTz last_send_time;
@@ -245,7 +256,8 @@ extern List *logicalrep_workers_find(Oid subid, bool only_running,
 extern bool logicalrep_worker_launch(LogicalRepWorkerType wtype,
 									 Oid dbid, Oid subid, const char *subname,
 									 Oid userid, Oid relid,
-									 dsm_handle subworker_dsm);
+									 dsm_handle subworker_dsm,
+									 bool retain_dead_tuples);
 extern void logicalrep_worker_stop(Oid subid, Oid relid);
 extern void logicalrep_pa_worker_stop(ParallelApplyWorkerInfo *winfo);
 extern void logicalrep_worker_wakeup(Oid subid, Oid relid);
diff --git a/src/include/storage/aio.h b/src/include/storage/aio.h
index e7a0a234b6cf2..2933eea064910 100644
--- a/src/include/storage/aio.h
+++ b/src/include/storage/aio.h
@@ -201,7 +201,7 @@ typedef enum PgAioHandleCallbackID
 } PgAioHandleCallbackID;
 
 #define PGAIO_HCB_MAX	PGAIO_HCB_LOCAL_BUFFER_READV
-StaticAssertDecl(PGAIO_HCB_MAX <= (1 << PGAIO_RESULT_ID_BITS),
+StaticAssertDecl(PGAIO_HCB_MAX < (1 << PGAIO_RESULT_ID_BITS),
 				 "PGAIO_HCB_MAX is too big for PGAIO_RESULT_ID_BITS");
 
 
diff --git a/src/include/storage/aio_types.h b/src/include/storage/aio_types.h
index 181833660778e..afee85c787b44 100644
--- a/src/include/storage/aio_types.h
+++ b/src/include/storage/aio_types.h
@@ -107,7 +107,7 @@ typedef struct PgAioResult
 	/* of type PgAioResultStatus, see above */
 	uint32		status:PGAIO_RESULT_STATUS_BITS;
 
-	/* meaning defined by callback->error */
+	/* meaning defined by callback->report */
 	uint32		error_data:PGAIO_RESULT_ERROR_BITS;
 
 	int32		result;
diff --git a/src/include/storage/buf_internals.h b/src/include/storage/buf_internals.h
index 0dec7d93b3b27..52a71b138f736 100644
--- a/src/include/storage/buf_internals.h
+++ b/src/include/storage/buf_internals.h
@@ -486,8 +486,8 @@ extern bool StartLocalBufferIO(BufferDesc *bufHdr, bool forInput, bool nowait);
 extern void FlushLocalBuffer(BufferDesc *bufHdr, SMgrRelation reln);
 extern void InvalidateLocalBuffer(BufferDesc *bufHdr, bool check_unreferenced);
 extern void DropRelationLocalBuffers(RelFileLocator rlocator,
-									 ForkNumber forkNum,
-									 BlockNumber firstDelBlock);
+									 ForkNumber *forkNum, int nforks,
+									 BlockNumber *firstDelBlock);
 extern void DropRelationAllLocalBuffers(RelFileLocator rlocator);
 extern void AtEOXact_LocalBuffers(bool isCommit);
 
diff --git a/src/include/storage/dsm_registry.h b/src/include/storage/dsm_registry.h
index b381e44bc9d87..4871ed509ebc6 100644
--- a/src/include/storage/dsm_registry.h
+++ b/src/include/storage/dsm_registry.h
@@ -13,10 +13,15 @@
 #ifndef DSM_REGISTRY_H
 #define DSM_REGISTRY_H
 
+#include "lib/dshash.h"
+
 extern void *GetNamedDSMSegment(const char *name, size_t size,
 								void (*init_callback) (void *ptr),
 								bool *found);
-
+extern dsa_area *GetNamedDSA(const char *name, bool *found);
+extern dshash_table *GetNamedDSHash(const char *name,
+									const dshash_parameters *params,
+									bool *found);
 extern Size DSMRegistryShmemSize(void);
 extern void DSMRegistryShmemInit(void);
 
diff --git a/src/include/storage/lock.h b/src/include/storage/lock.h
index 4862b80eec3c7..826cf28fdbd98 100644
--- a/src/include/storage/lock.h
+++ b/src/include/storage/lock.h
@@ -18,6 +18,7 @@
 #error "lock.h may not be included from frontend code"
 #endif
 
+#include "access/transam.h"
 #include "lib/ilist.h"
 #include "storage/lockdefs.h"
 #include "storage/lwlock.h"
@@ -581,7 +582,7 @@ extern bool LockHasWaiters(const LOCKTAG *locktag,
 extern VirtualTransactionId *GetLockConflicts(const LOCKTAG *locktag,
 											  LOCKMODE lockmode, int *countp);
 extern void AtPrepare_Locks(void);
-extern void PostPrepare_Locks(TransactionId xid);
+extern void PostPrepare_Locks(FullTransactionId fxid);
 extern bool LockCheckConflicts(LockMethod lockMethodTable,
 							   LOCKMODE lockmode,
 							   LOCK *lock, PROCLOCK *proclock);
@@ -597,13 +598,13 @@ extern BlockedProcsData *GetBlockerStatusData(int blocked_pid);
 extern xl_standby_lock *GetRunningTransactionLocks(int *nlocks);
 extern const char *GetLockmodeName(LOCKMETHODID lockmethodid, LOCKMODE mode);
 
-extern void lock_twophase_recover(TransactionId xid, uint16 info,
+extern void lock_twophase_recover(FullTransactionId fxid, uint16 info,
 								  void *recdata, uint32 len);
-extern void lock_twophase_postcommit(TransactionId xid, uint16 info,
+extern void lock_twophase_postcommit(FullTransactionId fxid, uint16 info,
 									 void *recdata, uint32 len);
-extern void lock_twophase_postabort(TransactionId xid, uint16 info,
+extern void lock_twophase_postabort(FullTransactionId fxid, uint16 info,
 									void *recdata, uint32 len);
-extern void lock_twophase_standby_recover(TransactionId xid, uint16 info,
+extern void lock_twophase_standby_recover(FullTransactionId fxid, uint16 info,
 										  void *recdata, uint32 len);
 
 extern DeadLockState DeadLockCheck(PGPROC *proc);
diff --git a/src/include/storage/lwlock.h b/src/include/storage/lwlock.h
index 08a72569ae5fd..5e717765764f4 100644
--- a/src/include/storage/lwlock.h
+++ b/src/include/storage/lwlock.h
@@ -176,51 +176,23 @@ extern void LWLockInitialize(LWLock *lock, int tranche_id);
  * Every tranche ID less than NUM_INDIVIDUAL_LWLOCKS is reserved; also,
  * we reserve additional tranche IDs for builtin tranches not included in
  * the set of individual LWLocks.  A call to LWLockNewTrancheId will never
- * return a value less than LWTRANCHE_FIRST_USER_DEFINED.
+ * return a value less than LWTRANCHE_FIRST_USER_DEFINED.  The actual list of
+ * built-in tranches is kept in lwlocklist.h.
  */
 typedef enum BuiltinTrancheIds
 {
-	LWTRANCHE_XACT_BUFFER = NUM_INDIVIDUAL_LWLOCKS,
-	LWTRANCHE_COMMITTS_BUFFER,
-	LWTRANCHE_SUBTRANS_BUFFER,
-	LWTRANCHE_MULTIXACTOFFSET_BUFFER,
-	LWTRANCHE_MULTIXACTMEMBER_BUFFER,
-	LWTRANCHE_NOTIFY_BUFFER,
-	LWTRANCHE_SERIAL_BUFFER,
-	LWTRANCHE_WAL_INSERT,
-	LWTRANCHE_BUFFER_CONTENT,
-	LWTRANCHE_REPLICATION_ORIGIN_STATE,
-	LWTRANCHE_REPLICATION_SLOT_IO,
-	LWTRANCHE_LOCK_FASTPATH,
-	LWTRANCHE_BUFFER_MAPPING,
-	LWTRANCHE_LOCK_MANAGER,
-	LWTRANCHE_PREDICATE_LOCK_MANAGER,
-	LWTRANCHE_PARALLEL_HASH_JOIN,
-	LWTRANCHE_PARALLEL_BTREE_SCAN,
-	LWTRANCHE_PARALLEL_QUERY_DSA,
-	LWTRANCHE_PER_SESSION_DSA,
-	LWTRANCHE_PER_SESSION_RECORD_TYPE,
-	LWTRANCHE_PER_SESSION_RECORD_TYPMOD,
-	LWTRANCHE_SHARED_TUPLESTORE,
-	LWTRANCHE_SHARED_TIDBITMAP,
-	LWTRANCHE_PARALLEL_APPEND,
-	LWTRANCHE_PER_XACT_PREDICATE_LIST,
-	LWTRANCHE_PGSTATS_DSA,
-	LWTRANCHE_PGSTATS_HASH,
-	LWTRANCHE_PGSTATS_DATA,
-	LWTRANCHE_LAUNCHER_DSA,
-	LWTRANCHE_LAUNCHER_HASH,
-	LWTRANCHE_DSM_REGISTRY_DSA,
-	LWTRANCHE_DSM_REGISTRY_HASH,
-	LWTRANCHE_COMMITTS_SLRU,
-	LWTRANCHE_MULTIXACTMEMBER_SLRU,
-	LWTRANCHE_MULTIXACTOFFSET_SLRU,
-	LWTRANCHE_NOTIFY_SLRU,
-	LWTRANCHE_SERIAL_SLRU,
-	LWTRANCHE_SUBTRANS_SLRU,
-	LWTRANCHE_XACT_SLRU,
-	LWTRANCHE_PARALLEL_VACUUM_DSA,
-	LWTRANCHE_AIO_URING_COMPLETION,
+	/*
+	 * LWTRANCHE_INVALID is an unused value that only exists to initialize the
+	 * rest of the tranches to appropriate values.
+	 */
+	LWTRANCHE_INVALID = NUM_INDIVIDUAL_LWLOCKS - 1,
+
+#define PG_LWLOCK(id, name)
+#define PG_LWLOCKTRANCHE(id, name) LWTRANCHE_##id,
+#include "storage/lwlocklist.h"
+#undef PG_LWLOCK
+#undef PG_LWLOCKTRANCHE
+
 	LWTRANCHE_FIRST_USER_DEFINED,
 }			BuiltinTrancheIds;
 
diff --git a/src/include/storage/lwlocklist.h b/src/include/storage/lwlocklist.h
index a9681738146e1..208d2e3a8ed9e 100644
--- a/src/include/storage/lwlocklist.h
+++ b/src/include/storage/lwlocklist.h
@@ -2,9 +2,10 @@
  *
  * lwlocklist.h
  *
- * The predefined LWLock list is kept in its own source file for use by
- * automatic tools.  The exact representation of a keyword is determined by
- * the PG_LWLOCK macro, which is not defined in this file; it can be
+ * The list of predefined LWLocks and built-in LWLock tranches is kept in
+ * its own source file for use by automatic tools.  The exact
+ * representation of a keyword is determined by the PG_LWLOCK and
+ * PG_LWLOCKTRANCHE macros, which are not defined in this file; they can be
  * defined by the caller for special purposes.
  *
  * Also, generate-lwlocknames.pl processes this file to create lwlocknames.h.
@@ -84,3 +85,53 @@ PG_LWLOCK(50, DSMRegistry)
 PG_LWLOCK(51, InjectionPoint)
 PG_LWLOCK(52, SerialControl)
 PG_LWLOCK(53, AioWorkerSubmissionQueue)
+
+/*
+ * There also exist several built-in LWLock tranches.  As with the predefined
+ * LWLocks, be sure to update the WaitEventLWLock section of
+ * src/backend/utils/activity/wait_event_names.txt when modifying this list.
+ *
+ * Note that the IDs here (the first value) don't include the LWTRANCHE_
+ * prefix.  It's added elsewhere.
+ */
+PG_LWLOCKTRANCHE(XACT_BUFFER, XactBuffer)
+PG_LWLOCKTRANCHE(COMMITTS_BUFFER, CommitTsBuffer)
+PG_LWLOCKTRANCHE(SUBTRANS_BUFFER, SubtransBuffer)
+PG_LWLOCKTRANCHE(MULTIXACTOFFSET_BUFFER, MultiXactOffsetBuffer)
+PG_LWLOCKTRANCHE(MULTIXACTMEMBER_BUFFER, MultiXactMemberBuffer)
+PG_LWLOCKTRANCHE(NOTIFY_BUFFER, NotifyBuffer)
+PG_LWLOCKTRANCHE(SERIAL_BUFFER, SerialBuffer)
+PG_LWLOCKTRANCHE(WAL_INSERT, WALInsert)
+PG_LWLOCKTRANCHE(BUFFER_CONTENT, BufferContent)
+PG_LWLOCKTRANCHE(REPLICATION_ORIGIN_STATE, ReplicationOriginState)
+PG_LWLOCKTRANCHE(REPLICATION_SLOT_IO, ReplicationSlotIO)
+PG_LWLOCKTRANCHE(LOCK_FASTPATH, LockFastPath)
+PG_LWLOCKTRANCHE(BUFFER_MAPPING, BufferMapping)
+PG_LWLOCKTRANCHE(LOCK_MANAGER, LockManager)
+PG_LWLOCKTRANCHE(PREDICATE_LOCK_MANAGER, PredicateLockManager)
+PG_LWLOCKTRANCHE(PARALLEL_HASH_JOIN, ParallelHashJoin)
+PG_LWLOCKTRANCHE(PARALLEL_BTREE_SCAN, ParallelBtreeScan)
+PG_LWLOCKTRANCHE(PARALLEL_QUERY_DSA, ParallelQueryDSA)
+PG_LWLOCKTRANCHE(PER_SESSION_DSA, PerSessionDSA)
+PG_LWLOCKTRANCHE(PER_SESSION_RECORD_TYPE, PerSessionRecordType)
+PG_LWLOCKTRANCHE(PER_SESSION_RECORD_TYPMOD, PerSessionRecordTypmod)
+PG_LWLOCKTRANCHE(SHARED_TUPLESTORE, SharedTupleStore)
+PG_LWLOCKTRANCHE(SHARED_TIDBITMAP, SharedTidBitmap)
+PG_LWLOCKTRANCHE(PARALLEL_APPEND, ParallelAppend)
+PG_LWLOCKTRANCHE(PER_XACT_PREDICATE_LIST, PerXactPredicateList)
+PG_LWLOCKTRANCHE(PGSTATS_DSA, PgStatsDSA)
+PG_LWLOCKTRANCHE(PGSTATS_HASH, PgStatsHash)
+PG_LWLOCKTRANCHE(PGSTATS_DATA, PgStatsData)
+PG_LWLOCKTRANCHE(LAUNCHER_DSA, LogicalRepLauncherDSA)
+PG_LWLOCKTRANCHE(LAUNCHER_HASH, LogicalRepLauncherHash)
+PG_LWLOCKTRANCHE(DSM_REGISTRY_DSA, DSMRegistryDSA)
+PG_LWLOCKTRANCHE(DSM_REGISTRY_HASH, DSMRegistryHash)
+PG_LWLOCKTRANCHE(COMMITTS_SLRU, CommitTsSLRU)
+PG_LWLOCKTRANCHE(MULTIXACTOFFSET_SLRU, MultiXactOffsetSLRU)
+PG_LWLOCKTRANCHE(MULTIXACTMEMBER_SLRU, MultiXactMemberSLRU)
+PG_LWLOCKTRANCHE(NOTIFY_SLRU, NotifySLRU)
+PG_LWLOCKTRANCHE(SERIAL_SLRU, SerialSLRU)
+PG_LWLOCKTRANCHE(SUBTRANS_SLRU, SubtransSLRU)
+PG_LWLOCKTRANCHE(XACT_SLRU, XactSLRU)
+PG_LWLOCKTRANCHE(PARALLEL_VACUUM_DSA, ParallelVacuumDSA)
+PG_LWLOCKTRANCHE(AIO_URING_COMPLETION, AioUringCompletion)
diff --git a/src/include/storage/predicate.h b/src/include/storage/predicate.h
index 267d5d90e9486..c1e3a4d9f64a7 100644
--- a/src/include/storage/predicate.h
+++ b/src/include/storage/predicate.h
@@ -72,9 +72,9 @@ extern void PreCommit_CheckForSerializationFailure(void);
 
 /* two-phase commit support */
 extern void AtPrepare_PredicateLocks(void);
-extern void PostPrepare_PredicateLocks(TransactionId xid);
-extern void PredicateLockTwoPhaseFinish(TransactionId xid, bool isCommit);
-extern void predicatelock_twophase_recover(TransactionId xid, uint16 info,
+extern void PostPrepare_PredicateLocks(FullTransactionId fxid);
+extern void PredicateLockTwoPhaseFinish(FullTransactionId xid, bool isCommit);
+extern void predicatelock_twophase_recover(FullTransactionId fxid, uint16 info,
 										   void *recdata, uint32 len);
 
 /* parallel query support */
diff --git a/src/include/storage/proc.h b/src/include/storage/proc.h
index 9f9b3fcfbf1d7..c6f5ebceefdd5 100644
--- a/src/include/storage/proc.h
+++ b/src/include/storage/proc.h
@@ -130,9 +130,17 @@ extern PGDLLIMPORT int FastPathLockGroupsPerBackend;
  * the checkpoint are actually destroyed on disk. Replay can cope with a file
  * or block that doesn't exist, but not with a block that has the wrong
  * contents.
+ *
+ * Setting DELAY_CHKPT_IN_COMMIT is similar to setting DELAY_CHKPT_START, but
+ * it explicitly indicates that the reason for delaying the checkpoint is due
+ * to a transaction being within a critical commit section. We need this new
+ * flag to ensure all the transactions that have acquired commit timestamp are
+ * finished before we allow the logical replication client to advance its xid
+ * which is used to hold back dead rows for conflict detection.
  */
 #define DELAY_CHKPT_START		(1<<0)
 #define DELAY_CHKPT_COMPLETE	(1<<1)
+#define DELAY_CHKPT_IN_COMMIT	(DELAY_CHKPT_START | 1<<2)
 
 typedef enum
 {
diff --git a/src/include/storage/procarray.h b/src/include/storage/procarray.h
index ef0b733ebe8be..2f4ae06c27932 100644
--- a/src/include/storage/procarray.h
+++ b/src/include/storage/procarray.h
@@ -53,10 +53,10 @@ extern bool ProcArrayInstallRestoredXmin(TransactionId xmin, PGPROC *proc);
 extern RunningTransactions GetRunningTransactionData(void);
 
 extern bool TransactionIdIsInProgress(TransactionId xid);
-extern bool TransactionIdIsActive(TransactionId xid);
 extern TransactionId GetOldestNonRemovableTransactionId(Relation rel);
 extern TransactionId GetOldestTransactionIdConsideredRunning(void);
-extern TransactionId GetOldestActiveTransactionId(void);
+extern TransactionId GetOldestActiveTransactionId(bool inCommitOnly,
+												  bool allDbs);
 extern TransactionId GetOldestSafeDecodingTransactionId(bool catalogOnly);
 extern void GetReplicationHorizons(TransactionId *xmin, TransactionId *catalog_xmin);
 
diff --git a/src/include/utils/catcache.h b/src/include/utils/catcache.h
index 277ec33c00bac..00808e23f49b8 100644
--- a/src/include/utils/catcache.h
+++ b/src/include/utils/catcache.h
@@ -87,6 +87,14 @@ typedef struct catcache
 
 typedef struct catctup
 {
+	/*
+	 * Each tuple in a cache is a member of a dlist that stores the elements
+	 * of its hash bucket.  We keep each dlist in LRU order to speed repeated
+	 * lookups.  Keep the dlist_node field first so that Valgrind understands
+	 * the struct is reachable.
+	 */
+	dlist_node	cache_elem;		/* list member of per-bucket list */
+
 	int			ct_magic;		/* for identifying CatCTup entries */
 #define CT_MAGIC   0x57261502
 
@@ -98,13 +106,6 @@ typedef struct catctup
 	 */
 	Datum		keys[CATCACHE_MAXKEYS];
 
-	/*
-	 * Each tuple in a cache is a member of a dlist that stores the elements
-	 * of its hash bucket.  We keep each dlist in LRU order to speed repeated
-	 * lookups.
-	 */
-	dlist_node	cache_elem;		/* list member of per-bucket list */
-
 	/*
 	 * A tuple marked "dead" must not be returned by subsequent searches.
 	 * However, it won't be physically deleted from the cache until its
@@ -158,13 +159,17 @@ typedef struct catctup
  */
 typedef struct catclist
 {
+	/*
+	 * Keep the dlist_node field first so that Valgrind understands the struct
+	 * is reachable.
+	 */
+	dlist_node	cache_elem;		/* list member of per-catcache list */
+
 	int			cl_magic;		/* for identifying CatCList entries */
 #define CL_MAGIC   0x52765103
 
 	uint32		hash_value;		/* hash value for lookup keys */
 
-	dlist_node	cache_elem;		/* list member of per-catcache list */
-
 	/*
 	 * Lookup keys for the entry, with the first nkeys elements being valid.
 	 * All by-reference are separately allocated.
diff --git a/src/include/utils/date.h b/src/include/utils/date.h
index bb5c1e57b073e..abfda0b1ae934 100644
--- a/src/include/utils/date.h
+++ b/src/include/utils/date.h
@@ -100,6 +100,8 @@ extern int32 anytime_typmod_check(bool istz, int32 typmod);
 extern double date2timestamp_no_overflow(DateADT dateVal);
 extern Timestamp date2timestamp_opt_overflow(DateADT dateVal, int *overflow);
 extern TimestampTz date2timestamptz_opt_overflow(DateADT dateVal, int *overflow);
+extern DateADT timestamp2date_opt_overflow(Timestamp timestamp, int *overflow);
+extern DateADT timestamptz2date_opt_overflow(TimestampTz timestamp, int *overflow);
 extern int32 date_cmp_timestamp_internal(DateADT dateVal, Timestamp dt2);
 extern int32 date_cmp_timestamptz_internal(DateADT dateVal, TimestampTz dt2);
 
diff --git a/src/include/utils/dsa.h b/src/include/utils/dsa.h
index 9eca87889087c..0a6067be6288b 100644
--- a/src/include/utils/dsa.h
+++ b/src/include/utils/dsa.h
@@ -145,6 +145,7 @@ extern dsa_area *dsa_create_in_place_ext(void *place, size_t size,
 										 size_t init_segment_size,
 										 size_t max_segment_size);
 extern dsa_area *dsa_attach(dsa_handle handle);
+extern bool dsa_is_attached(dsa_handle handle);
 extern dsa_area *dsa_attach_in_place(void *place, dsm_segment *segment);
 extern void dsa_release_in_place(void *place);
 extern void dsa_on_dsm_detach_release_in_place(dsm_segment *, Datum);
diff --git a/src/include/utils/guc_hooks.h b/src/include/utils/guc_hooks.h
index 799fa7ace6847..82ac8646a8d43 100644
--- a/src/include/utils/guc_hooks.h
+++ b/src/include/utils/guc_hooks.h
@@ -84,8 +84,6 @@ extern const char *show_log_timezone(void);
 extern void assign_maintenance_io_concurrency(int newval, void *extra);
 extern void assign_io_max_combine_limit(int newval, void *extra);
 extern void assign_io_combine_limit(int newval, void *extra);
-extern bool check_max_slot_wal_keep_size(int *newval, void **extra,
-										 GucSource source);
 extern void assign_max_wal_size(int newval, void *extra);
 extern bool check_max_stack_depth(int *newval, void **extra, GucSource source);
 extern void assign_max_stack_depth(int newval, void *extra);
@@ -176,7 +174,5 @@ extern void assign_wal_sync_method(int new_wal_sync_method, void *extra);
 extern bool check_synchronized_standby_slots(char **newval, void **extra,
 											 GucSource source);
 extern void assign_synchronized_standby_slots(const char *newval, void *extra);
-extern bool check_idle_replication_slot_timeout(int *newval, void **extra,
-												GucSource source);
 
 #endif							/* GUC_HOOKS_H */
diff --git a/src/include/utils/injection_point.h b/src/include/utils/injection_point.h
index a37958e1835fd..fd5bc061b7bdf 100644
--- a/src/include/utils/injection_point.h
+++ b/src/include/utils/injection_point.h
@@ -11,6 +11,19 @@
 #ifndef INJECTION_POINT_H
 #define INJECTION_POINT_H
 
+#include "nodes/pg_list.h"
+
+/*
+ * Injection point data, used when retrieving a list of all the attached
+ * injection points.
+ */
+typedef struct InjectionPointData
+{
+	const char *name;
+	const char *library;
+	const char *function;
+} InjectionPointData;
+
 /*
  * Injection points require --enable-injection-points.
  */
@@ -47,6 +60,9 @@ extern void InjectionPointCached(const char *name, void *arg);
 extern bool IsInjectionPointAttached(const char *name);
 extern bool InjectionPointDetach(const char *name);
 
+/* Get the current set of injection points attached */
+extern List *InjectionPointList(void);
+
 #ifdef EXEC_BACKEND
 extern PGDLLIMPORT struct InjectionPointsCtl *ActiveInjectionPoints;
 #endif
diff --git a/src/include/utils/memdebug.h b/src/include/utils/memdebug.h
index 7309271834b9f..80692dcef9382 100644
--- a/src/include/utils/memdebug.h
+++ b/src/include/utils/memdebug.h
@@ -29,6 +29,7 @@
 #define VALGRIND_MEMPOOL_ALLOC(context, addr, size)			do {} while (0)
 #define VALGRIND_MEMPOOL_FREE(context, addr)				do {} while (0)
 #define VALGRIND_MEMPOOL_CHANGE(context, optr, nptr, size)	do {} while (0)
+#define VALGRIND_MEMPOOL_TRIM(context, addr, size)			do {} while (0)
 #endif
 
 
diff --git a/src/include/utils/palloc.h b/src/include/utils/palloc.h
index e1b42267b22aa..039b9cba61a32 100644
--- a/src/include/utils/palloc.h
+++ b/src/include/utils/palloc.h
@@ -133,6 +133,8 @@ MemoryContextSwitchTo(MemoryContext context)
 /* Registration of memory context reset/delete callbacks */
 extern void MemoryContextRegisterResetCallback(MemoryContext context,
 											   MemoryContextCallback *cb);
+extern void MemoryContextUnregisterResetCallback(MemoryContext context,
+												 MemoryContextCallback *cb);
 
 /*
  * These are like standard strdup() except the copied string is
diff --git a/src/include/utils/pg_locale.h b/src/include/utils/pg_locale.h
index 7b8cbf58d2c43..931f5b3b88068 100644
--- a/src/include/utils/pg_locale.h
+++ b/src/include/utils/pg_locale.h
@@ -12,7 +12,12 @@
 #ifndef _PG_LOCALE_
 #define _PG_LOCALE_
 
+#include "mb/pg_wchar.h"
+
 #ifdef USE_ICU
+/* only include the C APIs, to avoid errors in cpluspluscheck */
+#undef U_SHOW_CPLUSPLUS_API
+#define U_SHOW_CPLUSPLUS_API 0
 #include <unicode/ucol.h>
 #endif
 
@@ -77,6 +82,52 @@ struct collate_methods
 	bool		strxfrm_is_safe;
 };
 
+struct ctype_methods
+{
+	/* case mapping: LOWER()/INITCAP()/UPPER() */
+	size_t		(*strlower) (char *dest, size_t destsize,
+							 const char *src, ssize_t srclen,
+							 pg_locale_t locale);
+	size_t		(*strtitle) (char *dest, size_t destsize,
+							 const char *src, ssize_t srclen,
+							 pg_locale_t locale);
+	size_t		(*strupper) (char *dest, size_t destsize,
+							 const char *src, ssize_t srclen,
+							 pg_locale_t locale);
+	size_t		(*strfold) (char *dest, size_t destsize,
+							const char *src, ssize_t srclen,
+							pg_locale_t locale);
+
+	/* required */
+	bool		(*wc_isdigit) (pg_wchar wc, pg_locale_t locale);
+	bool		(*wc_isalpha) (pg_wchar wc, pg_locale_t locale);
+	bool		(*wc_isalnum) (pg_wchar wc, pg_locale_t locale);
+	bool		(*wc_isupper) (pg_wchar wc, pg_locale_t locale);
+	bool		(*wc_islower) (pg_wchar wc, pg_locale_t locale);
+	bool		(*wc_isgraph) (pg_wchar wc, pg_locale_t locale);
+	bool		(*wc_isprint) (pg_wchar wc, pg_locale_t locale);
+	bool		(*wc_ispunct) (pg_wchar wc, pg_locale_t locale);
+	bool		(*wc_isspace) (pg_wchar wc, pg_locale_t locale);
+	pg_wchar	(*wc_toupper) (pg_wchar wc, pg_locale_t locale);
+	pg_wchar	(*wc_tolower) (pg_wchar wc, pg_locale_t locale);
+
+	/* required */
+	bool		(*char_is_cased) (char ch, pg_locale_t locale);
+
+	/*
+	 * Optional. If defined, will only be called for single-byte encodings. If
+	 * not defined, or if the encoding is multibyte, will fall back to
+	 * pg_strlower().
+	 */
+	char		(*char_tolower) (unsigned char ch, pg_locale_t locale);
+
+	/*
+	 * For regex and pattern matching efficiency, the maximum char value
+	 * supported by the above methods. If zero, limit is set by regex code.
+	 */
+	pg_wchar	max_chr;
+};
+
 /*
  * We use a discriminated union to hold either a locale_t or an ICU collator.
  * pg_locale_t is occasionally checked for truth, so make it a pointer.
@@ -95,13 +146,13 @@ struct collate_methods
  */
 struct pg_locale_struct
 {
-	char		provider;
 	bool		deterministic;
 	bool		collate_is_c;
 	bool		ctype_is_c;
 	bool		is_default;
 
 	const struct collate_methods *collate;	/* NULL if collate_is_c */
+	const struct ctype_methods *ctype;	/* NULL if ctype_is_c */
 
 	union
 	{
@@ -125,6 +176,10 @@ extern void init_database_collation(void);
 extern pg_locale_t pg_newlocale_from_collation(Oid collid);
 
 extern char *get_collation_actual_version(char collprovider, const char *collcollate);
+
+extern bool char_is_cased(char ch, pg_locale_t locale);
+extern bool char_tolower_enabled(pg_locale_t locale);
+extern char char_tolower(unsigned char ch, pg_locale_t locale);
 extern size_t pg_strlower(char *dst, size_t dstsize,
 						  const char *src, ssize_t srclen,
 						  pg_locale_t locale);
@@ -159,8 +214,8 @@ extern void report_newlocale_failure(const char *localename);
 
 /* These functions convert from/to libc's wchar_t, *not* pg_wchar_t */
 extern size_t wchar2char(char *to, const wchar_t *from, size_t tolen,
-						 pg_locale_t locale);
+						 locale_t loc);
 extern size_t char2wchar(wchar_t *to, size_t tolen,
-						 const char *from, size_t fromlen, pg_locale_t locale);
+						 const char *from, size_t fromlen, locale_t loc);
 
 #endif							/* _PG_LOCALE_ */
diff --git a/src/include/utils/pgstat_internal.h b/src/include/utils/pgstat_internal.h
index d5557e6e998cd..6cf00008f6333 100644
--- a/src/include/utils/pgstat_internal.h
+++ b/src/include/utils/pgstat_internal.h
@@ -295,18 +295,11 @@ typedef struct PgStat_KindInfo
 	 *
 	 * Returns true if some of the stats could not be flushed, due to lock
 	 * contention for example. Optional.
-	 */
-	bool		(*flush_static_cb) (bool nowait);
-
-	/*
-	 * For fixed-numbered or variable-numbered statistics: Check for pending
-	 * stats in need of flush with flush_static_cb, when these do not use
-	 * PgStat_EntryRef->pending.
 	 *
-	 * Returns true if there are any stats pending for flush, triggering
-	 * flush_static_cb. Optional.
+	 * "pgstat_report_fixed" needs to be set to trigger the flush of pending
+	 * stats.
 	 */
-	bool		(*have_static_pending_cb) (void);
+	bool		(*flush_static_cb) (bool nowait);
 
 	/*
 	 * For fixed-numbered statistics: Reset All.
@@ -627,7 +620,6 @@ extern void pgstat_archiver_snapshot_cb(void);
 
 extern bool pgstat_flush_backend(bool nowait, bits32 flags);
 extern bool pgstat_backend_flush_cb(bool nowait);
-extern bool pgstat_backend_have_pending_cb(void);
 extern void pgstat_backend_reset_timestamp_cb(PgStatShared_Common *header,
 											  TimestampTz ts);
 
@@ -676,7 +668,6 @@ extern bool pgstat_function_flush_cb(PgStat_EntryRef *entry_ref, bool nowait);
 
 extern void pgstat_flush_io(bool nowait);
 
-extern bool pgstat_io_have_pending_cb(void);
 extern bool pgstat_io_flush_cb(bool nowait);
 extern void pgstat_io_init_shmem_cb(void *stats);
 extern void pgstat_io_reset_all_cb(TimestampTz ts);
@@ -738,7 +729,6 @@ extern PgStatShared_Common *pgstat_init_entry(PgStat_Kind kind,
  * Functions in pgstat_slru.c
  */
 
-extern bool pgstat_slru_have_pending_cb(void);
 extern bool pgstat_slru_flush_cb(bool nowait);
 extern void pgstat_slru_init_shmem_cb(void *stats);
 extern void pgstat_slru_reset_all_cb(TimestampTz ts);
@@ -750,7 +740,6 @@ extern void pgstat_slru_snapshot_cb(void);
  */
 
 extern void pgstat_wal_init_backend_cb(void);
-extern bool pgstat_wal_have_pending_cb(void);
 extern bool pgstat_wal_flush_cb(bool nowait);
 extern void pgstat_wal_init_shmem_cb(void *stats);
 extern void pgstat_wal_reset_all_cb(TimestampTz ts);
@@ -778,8 +767,23 @@ extern void pgstat_create_transactional(PgStat_Kind kind, Oid dboid, uint64 obji
  * Variables in pgstat.c
  */
 
-extern PGDLLIMPORT PgStat_LocalState pgStatLocal;
+/*
+ * Track if *any* pending fixed-numbered statistics should be flushed to
+ * shared memory.
+ *
+ * This flag can be switched to true by fixed-numbered statistics to let
+ * pgstat_report_stat() know if it needs to go through one round of
+ * reports, calling flush_static_cb for each fixed-numbered statistics
+ * kind.  When this flag is not set, pgstat_report_stat() is able to do
+ * a fast exit, knowing that there are no pending fixed-numbered statistics.
+ *
+ * Statistics callbacks should never reset this flag; pgstat_report_stat()
+ * is in charge of doing that.
+ */
+extern PGDLLIMPORT bool pgstat_report_fixed;
 
+/* Backend-local stats state */
+extern PGDLLIMPORT PgStat_LocalState pgStatLocal;
 
 /*
  * Implementation of inline functions declared above.
diff --git a/src/include/utils/pgstat_kind.h b/src/include/utils/pgstat_kind.h
index f44169fd5a3c7..eb5f0b3ae6db7 100644
--- a/src/include/utils/pgstat_kind.h
+++ b/src/include/utils/pgstat_kind.h
@@ -18,7 +18,7 @@
 
 /* Range of IDs allowed, for built-in and custom kinds */
 #define PGSTAT_KIND_MIN	1		/* Minimum ID allowed */
-#define PGSTAT_KIND_MAX	256		/* Maximum ID allowed */
+#define PGSTAT_KIND_MAX	32		/* Maximum ID allowed */
 
 /* use 0 for INVALID, to catch zero-initialized data */
 #define PGSTAT_KIND_INVALID 0
@@ -46,7 +46,7 @@
 /* Custom stats kinds */
 
 /* Range of IDs allowed for custom stats kinds */
-#define PGSTAT_KIND_CUSTOM_MIN	128
+#define PGSTAT_KIND_CUSTOM_MIN	24
 #define PGSTAT_KIND_CUSTOM_MAX	PGSTAT_KIND_MAX
 #define PGSTAT_KIND_CUSTOM_SIZE	(PGSTAT_KIND_CUSTOM_MAX - PGSTAT_KIND_CUSTOM_MIN + 1)
 
@@ -55,7 +55,7 @@
  * development and have not reserved their own unique kind ID yet. See:
  * https://wiki.postgresql.org/wiki/CustomCumulativeStats
  */
-#define PGSTAT_KIND_EXPERIMENTAL	128
+#define PGSTAT_KIND_EXPERIMENTAL	24
 
 static inline bool
 pgstat_is_kind_builtin(PgStat_Kind kind)
diff --git a/src/include/utils/timestamp.h b/src/include/utils/timestamp.h
index 8c205859c3be5..93531732b085f 100644
--- a/src/include/utils/timestamp.h
+++ b/src/include/utils/timestamp.h
@@ -144,6 +144,9 @@ extern int	timestamp_cmp_internal(Timestamp dt1, Timestamp dt2);
 
 extern TimestampTz timestamp2timestamptz_opt_overflow(Timestamp timestamp,
 													  int *overflow);
+extern Timestamp timestamptz2timestamp_opt_overflow(TimestampTz timestamp,
+													int *overflow);
+
 extern int32 timestamp_cmp_timestamptz_internal(Timestamp timestampVal,
 												TimestampTz dt2);
 
diff --git a/src/include/varatt.h b/src/include/varatt.h
index 2e8564d49980b..aeeabf9145b59 100644
--- a/src/include/varatt.h
+++ b/src/include/varatt.h
@@ -89,20 +89,35 @@ typedef enum vartag_external
 	VARTAG_ONDISK = 18
 } vartag_external;
 
+/* Is a TOAST pointer either type of expanded-object pointer? */
 /* this test relies on the specific tag values above */
-#define VARTAG_IS_EXPANDED(tag) \
-	(((tag) & ~1) == VARTAG_EXPANDED_RO)
+static inline bool
+VARTAG_IS_EXPANDED(vartag_external tag)
+{
+	return ((tag & ~1) == VARTAG_EXPANDED_RO);
+}
 
-#define VARTAG_SIZE(tag) \
-	((tag) == VARTAG_INDIRECT ? sizeof(varatt_indirect) : \
-	 VARTAG_IS_EXPANDED(tag) ? sizeof(varatt_expanded) : \
-	 (tag) == VARTAG_ONDISK ? sizeof(varatt_external) : \
-	 (AssertMacro(false), 0))
+/* Size of the data part of a "TOAST pointer" datum */
+static inline Size
+VARTAG_SIZE(vartag_external tag)
+{
+	if (tag == VARTAG_INDIRECT)
+		return sizeof(varatt_indirect);
+	else if (VARTAG_IS_EXPANDED(tag))
+		return sizeof(varatt_expanded);
+	else if (tag == VARTAG_ONDISK)
+		return sizeof(varatt_external);
+	else
+	{
+		Assert(false);
+		return 0;
+	}
+}
 
 /*
  * These structs describe the header of a varlena object that may have been
  * TOASTed.  Generally, don't reference these structs directly, but use the
- * macros below.
+ * functions and macros below.
  *
  * We use separate structs for the aligned and unaligned cases because the
  * compiler might otherwise think it could generate code that assumes
@@ -166,7 +181,9 @@ typedef struct
 
 /*
  * Endian-dependent macros.  These are considered internal --- use the
- * external macros below instead of using these directly.
+ * external functions below instead of using these directly.  All of these
+ * expect an argument that is a pointer, not a Datum.  Some of them have
+ * multiple-evaluation hazards, too.
  *
  * Note: IS_1B is true for external toast records but VARSIZE_1B will return 0
  * for such records. Hence you should usually check for IS_EXTERNAL before
@@ -194,7 +211,7 @@ typedef struct
 #define VARSIZE_1B(PTR) \
 	(((varattrib_1b *) (PTR))->va_header & 0x7F)
 #define VARTAG_1B_E(PTR) \
-	(((varattrib_1b_e *) (PTR))->va_tag)
+	((vartag_external) ((varattrib_1b_e *) (PTR))->va_tag)
 
 #define SET_VARSIZE_4B(PTR,len) \
 	(((varattrib_4b *) (PTR))->va_4byte.va_header = (len) & 0x3FFFFFFF)
@@ -227,7 +244,7 @@ typedef struct
 #define VARSIZE_1B(PTR) \
 	((((varattrib_1b *) (PTR))->va_header >> 1) & 0x7F)
 #define VARTAG_1B_E(PTR) \
-	(((varattrib_1b_e *) (PTR))->va_tag)
+	((vartag_external) ((varattrib_1b_e *) (PTR))->va_tag)
 
 #define SET_VARSIZE_4B(PTR,len) \
 	(((varattrib_4b *) (PTR))->va_4byte.va_header = (((uint32) (len)) << 2))
@@ -247,19 +264,19 @@ typedef struct
 #define VARDATA_1B_E(PTR)	(((varattrib_1b_e *) (PTR))->va_data)
 
 /*
- * Externally visible TOAST macros begin here.
+ * Externally visible TOAST functions and macros begin here.  All of these
+ * were originally macros, accounting for the upper-case naming.
+ *
+ * Most of these functions accept a pointer to a value of a toastable data
+ * type.  The caller's variable might be declared "text *" or the like,
+ * so we use "void *" here.  Callers that are working with a Datum variable
+ * must apply DatumGetPointer before calling these functions.
  */
 
 #define VARHDRSZ_EXTERNAL		offsetof(varattrib_1b_e, va_data)
 #define VARHDRSZ_COMPRESSED		offsetof(varattrib_4b, va_compressed.va_data)
 #define VARHDRSZ_SHORT			offsetof(varattrib_1b, va_data)
-
 #define VARATT_SHORT_MAX		0x7F
-#define VARATT_CAN_MAKE_SHORT(PTR) \
-	(VARATT_IS_4B_U(PTR) && \
-	 (VARSIZE(PTR) - VARHDRSZ + VARHDRSZ_SHORT) <= VARATT_SHORT_MAX)
-#define VARATT_CONVERTED_SHORT_SIZE(PTR) \
-	(VARSIZE(PTR) - VARHDRSZ + VARHDRSZ_SHORT)
 
 /*
  * In consumers oblivious to data alignment, call PG_DETOAST_DATUM_PACKED(),
@@ -272,70 +289,234 @@ typedef struct
  * Code assembling a new datum should call VARDATA() and SET_VARSIZE().
  * (Datums begin life untoasted.)
  *
- * Other macros here should usually be used only by tuple assembly/disassembly
+ * Other functions here should usually be used only by tuple assembly/disassembly
  * code and code that specifically wants to work with still-toasted Datums.
  */
-#define VARDATA(PTR)						VARDATA_4B(PTR)
-#define VARSIZE(PTR)						VARSIZE_4B(PTR)
-
-#define VARSIZE_SHORT(PTR)					VARSIZE_1B(PTR)
-#define VARDATA_SHORT(PTR)					VARDATA_1B(PTR)
-
-#define VARTAG_EXTERNAL(PTR)				VARTAG_1B_E(PTR)
-#define VARSIZE_EXTERNAL(PTR)				(VARHDRSZ_EXTERNAL + VARTAG_SIZE(VARTAG_EXTERNAL(PTR)))
-#define VARDATA_EXTERNAL(PTR)				VARDATA_1B_E(PTR)
-
-#define VARATT_IS_COMPRESSED(PTR)			VARATT_IS_4B_C(PTR)
-#define VARATT_IS_EXTERNAL(PTR)				VARATT_IS_1B_E(PTR)
-#define VARATT_IS_EXTERNAL_ONDISK(PTR) \
-	(VARATT_IS_EXTERNAL(PTR) && VARTAG_EXTERNAL(PTR) == VARTAG_ONDISK)
-#define VARATT_IS_EXTERNAL_INDIRECT(PTR) \
-	(VARATT_IS_EXTERNAL(PTR) && VARTAG_EXTERNAL(PTR) == VARTAG_INDIRECT)
-#define VARATT_IS_EXTERNAL_EXPANDED_RO(PTR) \
-	(VARATT_IS_EXTERNAL(PTR) && VARTAG_EXTERNAL(PTR) == VARTAG_EXPANDED_RO)
-#define VARATT_IS_EXTERNAL_EXPANDED_RW(PTR) \
-	(VARATT_IS_EXTERNAL(PTR) && VARTAG_EXTERNAL(PTR) == VARTAG_EXPANDED_RW)
-#define VARATT_IS_EXTERNAL_EXPANDED(PTR) \
-	(VARATT_IS_EXTERNAL(PTR) && VARTAG_IS_EXPANDED(VARTAG_EXTERNAL(PTR)))
-#define VARATT_IS_EXTERNAL_NON_EXPANDED(PTR) \
-	(VARATT_IS_EXTERNAL(PTR) && !VARTAG_IS_EXPANDED(VARTAG_EXTERNAL(PTR)))
-#define VARATT_IS_SHORT(PTR)				VARATT_IS_1B(PTR)
-#define VARATT_IS_EXTENDED(PTR)				(!VARATT_IS_4B_U(PTR))
-
-#define SET_VARSIZE(PTR, len)				SET_VARSIZE_4B(PTR, len)
-#define SET_VARSIZE_SHORT(PTR, len)			SET_VARSIZE_1B(PTR, len)
-#define SET_VARSIZE_COMPRESSED(PTR, len)	SET_VARSIZE_4B_C(PTR, len)
-
-#define SET_VARTAG_EXTERNAL(PTR, tag)		SET_VARTAG_1B_E(PTR, tag)
-
-#define VARSIZE_ANY(PTR) \
-	(VARATT_IS_1B_E(PTR) ? VARSIZE_EXTERNAL(PTR) : \
-	 (VARATT_IS_1B(PTR) ? VARSIZE_1B(PTR) : \
-	  VARSIZE_4B(PTR)))
-
-/* Size of a varlena data, excluding header */
-#define VARSIZE_ANY_EXHDR(PTR) \
-	(VARATT_IS_1B_E(PTR) ? VARSIZE_EXTERNAL(PTR)-VARHDRSZ_EXTERNAL : \
-	 (VARATT_IS_1B(PTR) ? VARSIZE_1B(PTR)-VARHDRSZ_SHORT : \
-	  VARSIZE_4B(PTR)-VARHDRSZ))
 
+/* Size of a known-not-toasted varlena datum, including header */
+static inline Size
+VARSIZE(const void *PTR)
+{
+	return VARSIZE_4B(PTR);
+}
+
+/* Start of data area of a known-not-toasted varlena datum */
+static inline char *
+VARDATA(const void *PTR)
+{
+	return VARDATA_4B(PTR);
+}
+
+/* Size of a known-short-header varlena datum, including header */
+static inline Size
+VARSIZE_SHORT(const void *PTR)
+{
+	return VARSIZE_1B(PTR);
+}
+
+/* Start of data area of a known-short-header varlena datum */
+static inline char *
+VARDATA_SHORT(const void *PTR)
+{
+	return VARDATA_1B(PTR);
+}
+
+/* Type tag of a "TOAST pointer" datum */
+static inline vartag_external
+VARTAG_EXTERNAL(const void *PTR)
+{
+	return VARTAG_1B_E(PTR);
+}
+
+/* Size of a "TOAST pointer" datum, including header */
+static inline Size
+VARSIZE_EXTERNAL(const void *PTR)
+{
+	return VARHDRSZ_EXTERNAL + VARTAG_SIZE(VARTAG_EXTERNAL(PTR));
+}
+
+/* Start of data area of a "TOAST pointer" datum */
+static inline char *
+VARDATA_EXTERNAL(const void *PTR)
+{
+	return VARDATA_1B_E(PTR);
+}
+
+/* Is varlena datum in inline-compressed format? */
+static inline bool
+VARATT_IS_COMPRESSED(const void *PTR)
+{
+	return VARATT_IS_4B_C(PTR);
+}
+
+/* Is varlena datum a "TOAST pointer" datum? */
+static inline bool
+VARATT_IS_EXTERNAL(const void *PTR)
+{
+	return VARATT_IS_1B_E(PTR);
+}
+
+/* Is varlena datum a pointer to on-disk toasted data? */
+static inline bool
+VARATT_IS_EXTERNAL_ONDISK(const void *PTR)
+{
+	return VARATT_IS_EXTERNAL(PTR) && VARTAG_EXTERNAL(PTR) == VARTAG_ONDISK;
+}
+
+/* Is varlena datum an indirect pointer? */
+static inline bool
+VARATT_IS_EXTERNAL_INDIRECT(const void *PTR)
+{
+	return VARATT_IS_EXTERNAL(PTR) && VARTAG_EXTERNAL(PTR) == VARTAG_INDIRECT;
+}
+
+/* Is varlena datum a read-only pointer to an expanded object? */
+static inline bool
+VARATT_IS_EXTERNAL_EXPANDED_RO(const void *PTR)
+{
+	return VARATT_IS_EXTERNAL(PTR) && VARTAG_EXTERNAL(PTR) == VARTAG_EXPANDED_RO;
+}
+
+/* Is varlena datum a read-write pointer to an expanded object? */
+static inline bool
+VARATT_IS_EXTERNAL_EXPANDED_RW(const void *PTR)
+{
+	return VARATT_IS_EXTERNAL(PTR) && VARTAG_EXTERNAL(PTR) == VARTAG_EXPANDED_RW;
+}
+
+/* Is varlena datum either type of pointer to an expanded object? */
+static inline bool
+VARATT_IS_EXTERNAL_EXPANDED(const void *PTR)
+{
+	return VARATT_IS_EXTERNAL(PTR) && VARTAG_IS_EXPANDED(VARTAG_EXTERNAL(PTR));
+}
+
+/* Is varlena datum a "TOAST pointer", but not for an expanded object? */
+static inline bool
+VARATT_IS_EXTERNAL_NON_EXPANDED(const void *PTR)
+{
+	return VARATT_IS_EXTERNAL(PTR) && !VARTAG_IS_EXPANDED(VARTAG_EXTERNAL(PTR));
+}
+
+/* Is varlena datum a short-header datum? */
+static inline bool
+VARATT_IS_SHORT(const void *PTR)
+{
+	return VARATT_IS_1B(PTR);
+}
+
+/* Is varlena datum not in traditional (4-byte-header, uncompressed) format? */
+static inline bool
+VARATT_IS_EXTENDED(const void *PTR)
+{
+	return !VARATT_IS_4B_U(PTR);
+}
+
+/* Is varlena datum short enough to convert to short-header format? */
+static inline bool
+VARATT_CAN_MAKE_SHORT(const void *PTR)
+{
+	return VARATT_IS_4B_U(PTR) &&
+		(VARSIZE(PTR) - VARHDRSZ + VARHDRSZ_SHORT) <= VARATT_SHORT_MAX;
+}
+
+/* Size that datum will have in short-header format, including header */
+static inline Size
+VARATT_CONVERTED_SHORT_SIZE(const void *PTR)
+{
+	return VARSIZE(PTR) - VARHDRSZ + VARHDRSZ_SHORT;
+}
+
+/* Set the size (including header) of a 4-byte-header varlena datum */
+static inline void
+SET_VARSIZE(void *PTR, Size len)
+{
+	SET_VARSIZE_4B(PTR, len);
+}
+
+/* Set the size (including header) of a short-header varlena datum */
+static inline void
+SET_VARSIZE_SHORT(void *PTR, Size len)
+{
+	SET_VARSIZE_1B(PTR, len);
+}
+
+/* Set the size (including header) of an inline-compressed varlena datum */
+static inline void
+SET_VARSIZE_COMPRESSED(void *PTR, Size len)
+{
+	SET_VARSIZE_4B_C(PTR, len);
+}
+
+/* Set the type tag of a "TOAST pointer" datum */
+static inline void
+SET_VARTAG_EXTERNAL(void *PTR, vartag_external tag)
+{
+	SET_VARTAG_1B_E(PTR, tag);
+}
+
+/* Size of a varlena datum of any format, including header */
+static inline Size
+VARSIZE_ANY(const void *PTR)
+{
+	if (VARATT_IS_1B_E(PTR))
+		return VARSIZE_EXTERNAL(PTR);
+	else if (VARATT_IS_1B(PTR))
+		return VARSIZE_1B(PTR);
+	else
+		return VARSIZE_4B(PTR);
+}
+
+/* Size of a varlena datum of any format, excluding header */
+static inline Size
+VARSIZE_ANY_EXHDR(const void *PTR)
+{
+	if (VARATT_IS_1B_E(PTR))
+		return VARSIZE_EXTERNAL(PTR) - VARHDRSZ_EXTERNAL;
+	else if (VARATT_IS_1B(PTR))
+		return VARSIZE_1B(PTR) - VARHDRSZ_SHORT;
+	else
+		return VARSIZE_4B(PTR) - VARHDRSZ;
+}
+
+/* Start of data area of a plain or short-header varlena datum */
 /* caution: this will not work on an external or compressed-in-line Datum */
 /* caution: this will return a possibly unaligned pointer */
-#define VARDATA_ANY(PTR) \
-	 (VARATT_IS_1B(PTR) ? VARDATA_1B(PTR) : VARDATA_4B(PTR))
+static inline char *
+VARDATA_ANY(const void *PTR)
+{
+	return VARATT_IS_1B(PTR) ? VARDATA_1B(PTR) : VARDATA_4B(PTR);
+}
 
-/* Decompressed size and compression method of a compressed-in-line Datum */
-#define VARDATA_COMPRESSED_GET_EXTSIZE(PTR) \
-	(((varattrib_4b *) (PTR))->va_compressed.va_tcinfo & VARLENA_EXTSIZE_MASK)
-#define VARDATA_COMPRESSED_GET_COMPRESS_METHOD(PTR) \
-	(((varattrib_4b *) (PTR))->va_compressed.va_tcinfo >> VARLENA_EXTSIZE_BITS)
+/* Decompressed size of a compressed-in-line varlena datum */
+static inline Size
+VARDATA_COMPRESSED_GET_EXTSIZE(const void *PTR)
+{
+	return ((varattrib_4b *) PTR)->va_compressed.va_tcinfo & VARLENA_EXTSIZE_MASK;
+}
+
+/* Compression method of a compressed-in-line varlena datum */
+static inline uint32
+VARDATA_COMPRESSED_GET_COMPRESS_METHOD(const void *PTR)
+{
+	return ((varattrib_4b *) PTR)->va_compressed.va_tcinfo >> VARLENA_EXTSIZE_BITS;
+}
 
 /* Same for external Datums; but note argument is a struct varatt_external */
-#define VARATT_EXTERNAL_GET_EXTSIZE(toast_pointer) \
-	((toast_pointer).va_extinfo & VARLENA_EXTSIZE_MASK)
-#define VARATT_EXTERNAL_GET_COMPRESS_METHOD(toast_pointer) \
-	((toast_pointer).va_extinfo >> VARLENA_EXTSIZE_BITS)
+static inline Size
+VARATT_EXTERNAL_GET_EXTSIZE(struct varatt_external toast_pointer)
+{
+	return toast_pointer.va_extinfo & VARLENA_EXTSIZE_MASK;
+}
 
+static inline uint32
+VARATT_EXTERNAL_GET_COMPRESS_METHOD(struct varatt_external toast_pointer)
+{
+	return toast_pointer.va_extinfo >> VARLENA_EXTSIZE_BITS;
+}
+
+/* Set size and compress method of an externally-stored varlena datum */
+/* This has to remain a macro; beware multiple evaluations! */
 #define VARATT_EXTERNAL_SET_SIZE_AND_COMPRESS_METHOD(toast_pointer, len, cm) \
 	do { \
 		Assert((cm) == TOAST_PGLZ_COMPRESSION_ID || \
@@ -351,8 +532,11 @@ typedef struct
  * VARHDRSZ overhead, the former doesn't.  We never use compression unless it
  * actually saves space, so we expect either equality or less-than.
  */
-#define VARATT_EXTERNAL_IS_COMPRESSED(toast_pointer) \
-	(VARATT_EXTERNAL_GET_EXTSIZE(toast_pointer) < \
-	 (toast_pointer).va_rawsize - VARHDRSZ)
+static inline bool
+VARATT_EXTERNAL_IS_COMPRESSED(struct varatt_external toast_pointer)
+{
+	return VARATT_EXTERNAL_GET_EXTSIZE(toast_pointer) <
+		(Size) (toast_pointer.va_rawsize - VARHDRSZ);
+}
 
 #endif
diff --git a/src/interfaces/ecpg/ecpglib/connect.c b/src/interfaces/ecpg/ecpglib/connect.c
index 2bbb70333dcb4..78de9f298ba62 100644
--- a/src/interfaces/ecpg/ecpglib/connect.c
+++ b/src/interfaces/ecpg/ecpglib/connect.c
@@ -58,7 +58,12 @@ ecpg_get_connection_nr(const char *connection_name)
 
 		for (con = all_connections; con != NULL; con = con->next)
 		{
-			if (strcmp(connection_name, con->name) == 0)
+			/*
+			 * Check for the case of a NULL connection name, stored as such in
+			 * the connection information by ECPGconnect() when the database
+			 * name is not specified by its caller.
+			 */
+			if (con->name != NULL && strcmp(connection_name, con->name) == 0)
 				break;
 		}
 		ret = con;
@@ -259,7 +264,8 @@ ECPGconnect(int lineno, int c, const char *name, const char *user, const char *p
 	struct connection *this;
 	int			i,
 				connect_params = 0;
-	char	   *dbname = name ? ecpg_strdup(name, lineno) : NULL,
+	bool		alloc_failed = (sqlca == NULL);
+	char	   *dbname = name ? ecpg_strdup(name, lineno, &alloc_failed) : NULL,
 			   *host = NULL,
 			   *tmp,
 			   *port = NULL,
@@ -268,11 +274,12 @@ ECPGconnect(int lineno, int c, const char *name, const char *user, const char *p
 	const char **conn_keywords;
 	const char **conn_values;
 
-	if (sqlca == NULL)
+	if (alloc_failed)
 	{
 		ecpg_raise(lineno, ECPG_OUT_OF_MEMORY,
 				   ECPG_SQLSTATE_ECPG_OUT_OF_MEMORY, NULL);
-		ecpg_free(dbname);
+		if (dbname)
+			ecpg_free(dbname);
 		return false;
 	}
 
@@ -297,7 +304,7 @@ ECPGconnect(int lineno, int c, const char *name, const char *user, const char *p
 		if (envname)
 		{
 			ecpg_free(dbname);
-			dbname = ecpg_strdup(envname, lineno);
+			dbname = ecpg_strdup(envname, lineno, &alloc_failed);
 		}
 	}
 
@@ -349,7 +356,7 @@ ECPGconnect(int lineno, int c, const char *name, const char *user, const char *p
 				tmp = strrchr(dbname + offset, '?');
 				if (tmp != NULL)	/* options given */
 				{
-					options = ecpg_strdup(tmp + 1, lineno);
+					options = ecpg_strdup(tmp + 1, lineno, &alloc_failed);
 					*tmp = '\0';
 				}
 
@@ -358,7 +365,7 @@ ECPGconnect(int lineno, int c, const char *name, const char *user, const char *p
 				{
 					if (tmp[1] != '\0') /* non-empty database name */
 					{
-						realname = ecpg_strdup(tmp + 1, lineno);
+						realname = ecpg_strdup(tmp + 1, lineno, &alloc_failed);
 						connect_params++;
 					}
 					*tmp = '\0';
@@ -368,7 +375,7 @@ ECPGconnect(int lineno, int c, const char *name, const char *user, const char *p
 				if (tmp != NULL)	/* port number given */
 				{
 					*tmp = '\0';
-					port = ecpg_strdup(tmp + 1, lineno);
+					port = ecpg_strdup(tmp + 1, lineno, &alloc_failed);
 					connect_params++;
 				}
 
@@ -402,7 +409,7 @@ ECPGconnect(int lineno, int c, const char *name, const char *user, const char *p
 				{
 					if (*(dbname + offset) != '\0')
 					{
-						host = ecpg_strdup(dbname + offset, lineno);
+						host = ecpg_strdup(dbname + offset, lineno, &alloc_failed);
 						connect_params++;
 					}
 				}
@@ -414,7 +421,7 @@ ECPGconnect(int lineno, int c, const char *name, const char *user, const char *p
 			tmp = strrchr(dbname, ':');
 			if (tmp != NULL)	/* port number given */
 			{
-				port = ecpg_strdup(tmp + 1, lineno);
+				port = ecpg_strdup(tmp + 1, lineno, &alloc_failed);
 				connect_params++;
 				*tmp = '\0';
 			}
@@ -422,14 +429,14 @@ ECPGconnect(int lineno, int c, const char *name, const char *user, const char *p
 			tmp = strrchr(dbname, '@');
 			if (tmp != NULL)	/* host name given */
 			{
-				host = ecpg_strdup(tmp + 1, lineno);
+				host = ecpg_strdup(tmp + 1, lineno, &alloc_failed);
 				connect_params++;
 				*tmp = '\0';
 			}
 
 			if (strlen(dbname) > 0)
 			{
-				realname = ecpg_strdup(dbname, lineno);
+				realname = ecpg_strdup(dbname, lineno, &alloc_failed);
 				connect_params++;
 			}
 			else
@@ -460,7 +467,18 @@ ECPGconnect(int lineno, int c, const char *name, const char *user, const char *p
 	 */
 	conn_keywords = (const char **) ecpg_alloc((connect_params + 1) * sizeof(char *), lineno);
 	conn_values = (const char **) ecpg_alloc(connect_params * sizeof(char *), lineno);
-	if (conn_keywords == NULL || conn_values == NULL)
+
+	/* Decide on a connection name */
+	if (connection_name != NULL || realname != NULL)
+	{
+		this->name = ecpg_strdup(connection_name ? connection_name : realname,
+								 lineno, &alloc_failed);
+	}
+	else
+		this->name = NULL;
+
+	/* Deal with any failed allocations above */
+	if (conn_keywords == NULL || conn_values == NULL || alloc_failed)
 	{
 		if (host)
 			ecpg_free(host);
@@ -476,6 +494,8 @@ ECPGconnect(int lineno, int c, const char *name, const char *user, const char *p
 			ecpg_free(conn_keywords);
 		if (conn_values)
 			ecpg_free(conn_values);
+		if (this->name)
+			ecpg_free(this->name);
 		free(this);
 		return false;
 	}
@@ -510,17 +530,14 @@ ECPGconnect(int lineno, int c, const char *name, const char *user, const char *p
 				ecpg_free(conn_keywords);
 			if (conn_values)
 				ecpg_free(conn_values);
+			if (this->name)
+				ecpg_free(this->name);
 			free(this);
 			return false;
 		}
 	}
 #endif
 
-	if (connection_name != NULL)
-		this->name = ecpg_strdup(connection_name, lineno);
-	else
-		this->name = ecpg_strdup(realname, lineno);
-
 	this->cache_head = NULL;
 	this->prep_stmts = NULL;
 
diff --git a/src/interfaces/ecpg/ecpglib/descriptor.c b/src/interfaces/ecpg/ecpglib/descriptor.c
index 651d5c8b2ed3c..466428edfebee 100644
--- a/src/interfaces/ecpg/ecpglib/descriptor.c
+++ b/src/interfaces/ecpg/ecpglib/descriptor.c
@@ -240,8 +240,9 @@ ECPGget_desc(int lineno, const char *desc_name, int index,...)
 				act_tuple;
 	struct variable data_var;
 	struct sqlca_t *sqlca = ECPGget_sqlca();
+	bool		alloc_failed = (sqlca == NULL);
 
-	if (sqlca == NULL)
+	if (alloc_failed)
 	{
 		ecpg_raise(lineno, ECPG_OUT_OF_MEMORY,
 				   ECPG_SQLSTATE_ECPG_OUT_OF_MEMORY, NULL);
@@ -493,7 +494,14 @@ ECPGget_desc(int lineno, const char *desc_name, int index,...)
 #ifdef WIN32
 		stmt.oldthreadlocale = _configthreadlocale(_ENABLE_PER_THREAD_LOCALE);
 #endif
-		stmt.oldlocale = ecpg_strdup(setlocale(LC_NUMERIC, NULL), lineno);
+		stmt.oldlocale = ecpg_strdup(setlocale(LC_NUMERIC, NULL),
+									 lineno, &alloc_failed);
+		if (alloc_failed)
+		{
+			va_end(args);
+			return false;
+		}
+
 		setlocale(LC_NUMERIC, "C");
 #endif
 
diff --git a/src/interfaces/ecpg/ecpglib/ecpglib_extern.h b/src/interfaces/ecpg/ecpglib/ecpglib_extern.h
index 75cc68275bdac..949ff66cefc92 100644
--- a/src/interfaces/ecpg/ecpglib/ecpglib_extern.h
+++ b/src/interfaces/ecpg/ecpglib/ecpglib_extern.h
@@ -175,7 +175,7 @@ void		ecpg_free(void *ptr);
 bool		ecpg_init(const struct connection *con,
 					  const char *connection_name,
 					  const int lineno);
-char	   *ecpg_strdup(const char *string, int lineno);
+char	   *ecpg_strdup(const char *string, int lineno, bool *alloc_failed);
 const char *ecpg_type_name(enum ECPGttype typ);
 int			ecpg_dynamic_type(Oid type);
 int			sqlda_dynamic_type(Oid type, enum COMPAT_MODE compat);
diff --git a/src/interfaces/ecpg/ecpglib/execute.c b/src/interfaces/ecpg/ecpglib/execute.c
index f52da06de9a1d..84a4a9fc5781f 100644
--- a/src/interfaces/ecpg/ecpglib/execute.c
+++ b/src/interfaces/ecpg/ecpglib/execute.c
@@ -860,9 +860,9 @@ ecpg_store_input(const int lineno, const bool force_indicator, const struct vari
 					numeric    *nval;
 
 					if (var->arrsize > 1)
-						mallocedval = ecpg_strdup("{", lineno);
+						mallocedval = ecpg_strdup("{", lineno, NULL);
 					else
-						mallocedval = ecpg_strdup("", lineno);
+						mallocedval = ecpg_strdup("", lineno, NULL);
 
 					if (!mallocedval)
 						return false;
@@ -923,9 +923,9 @@ ecpg_store_input(const int lineno, const bool force_indicator, const struct vari
 					int			slen;
 
 					if (var->arrsize > 1)
-						mallocedval = ecpg_strdup("{", lineno);
+						mallocedval = ecpg_strdup("{", lineno, NULL);
 					else
-						mallocedval = ecpg_strdup("", lineno);
+						mallocedval = ecpg_strdup("", lineno, NULL);
 
 					if (!mallocedval)
 						return false;
@@ -970,9 +970,9 @@ ecpg_store_input(const int lineno, const bool force_indicator, const struct vari
 					int			slen;
 
 					if (var->arrsize > 1)
-						mallocedval = ecpg_strdup("{", lineno);
+						mallocedval = ecpg_strdup("{", lineno, NULL);
 					else
-						mallocedval = ecpg_strdup("", lineno);
+						mallocedval = ecpg_strdup("", lineno, NULL);
 
 					if (!mallocedval)
 						return false;
@@ -1017,9 +1017,9 @@ ecpg_store_input(const int lineno, const bool force_indicator, const struct vari
 					int			slen;
 
 					if (var->arrsize > 1)
-						mallocedval = ecpg_strdup("{", lineno);
+						mallocedval = ecpg_strdup("{", lineno, NULL);
 					else
-						mallocedval = ecpg_strdup("", lineno);
+						mallocedval = ecpg_strdup("", lineno, NULL);
 
 					if (!mallocedval)
 						return false;
@@ -2001,7 +2001,8 @@ ecpg_do_prologue(int lineno, const int compat, const int force_indicator,
 		return false;
 	}
 #endif
-	stmt->oldlocale = ecpg_strdup(setlocale(LC_NUMERIC, NULL), lineno);
+	stmt->oldlocale = ecpg_strdup(setlocale(LC_NUMERIC, NULL), lineno,
+								  NULL);
 	if (stmt->oldlocale == NULL)
 	{
 		ecpg_do_epilogue(stmt);
@@ -2030,7 +2031,14 @@ ecpg_do_prologue(int lineno, const int compat, const int force_indicator,
 		statement_type = ECPGst_execute;
 	}
 	else
-		stmt->command = ecpg_strdup(query, lineno);
+	{
+		stmt->command = ecpg_strdup(query, lineno, NULL);
+		if (!stmt->command)
+		{
+			ecpg_do_epilogue(stmt);
+			return false;
+		}
+	}
 
 	stmt->name = NULL;
 
@@ -2042,7 +2050,12 @@ ecpg_do_prologue(int lineno, const int compat, const int force_indicator,
 		if (command)
 		{
 			stmt->name = stmt->command;
-			stmt->command = ecpg_strdup(command, lineno);
+			stmt->command = ecpg_strdup(command, lineno, NULL);
+			if (!stmt->command)
+			{
+				ecpg_do_epilogue(stmt);
+				return false;
+			}
 		}
 		else
 		{
@@ -2175,7 +2188,12 @@ ecpg_do_prologue(int lineno, const int compat, const int force_indicator,
 
 			if (!is_prepared_name_set && stmt->statement_type == ECPGst_prepare)
 			{
-				stmt->name = ecpg_strdup(var->value, lineno);
+				stmt->name = ecpg_strdup(var->value, lineno, NULL);
+				if (!stmt->name)
+				{
+					ecpg_do_epilogue(stmt);
+					return false;
+				}
 				is_prepared_name_set = true;
 			}
 		}
diff --git a/src/interfaces/ecpg/ecpglib/memory.c b/src/interfaces/ecpg/ecpglib/memory.c
index 6979be2c988ac..2112e55b6e42c 100644
--- a/src/interfaces/ecpg/ecpglib/memory.c
+++ b/src/interfaces/ecpg/ecpglib/memory.c
@@ -43,8 +43,15 @@ ecpg_realloc(void *ptr, long size, int lineno)
 	return new;
 }
 
+/*
+ * Wrapper for strdup(), with NULL in input treated as a correct case.
+ *
+ * "alloc_failed" can be optionally specified by the caller to check for
+ * allocation failures.  The caller is responsible for its initialization,
+ * as ecpg_strdup() may be called repeatedly across multiple allocations.
+ */
 char *
-ecpg_strdup(const char *string, int lineno)
+ecpg_strdup(const char *string, int lineno, bool *alloc_failed)
 {
 	char	   *new;
 
@@ -54,6 +61,8 @@ ecpg_strdup(const char *string, int lineno)
 	new = strdup(string);
 	if (!new)
 	{
+		if (alloc_failed)
+			*alloc_failed = true;
 		ecpg_raise(lineno, ECPG_OUT_OF_MEMORY, ECPG_SQLSTATE_ECPG_OUT_OF_MEMORY, NULL);
 		return NULL;
 	}
diff --git a/src/interfaces/ecpg/ecpglib/prepare.c b/src/interfaces/ecpg/ecpglib/prepare.c
index ea1146f520f34..06f0135813b37 100644
--- a/src/interfaces/ecpg/ecpglib/prepare.c
+++ b/src/interfaces/ecpg/ecpglib/prepare.c
@@ -85,9 +85,22 @@ ecpg_register_prepared_stmt(struct statement *stmt)
 	/* create statement */
 	prep_stmt->lineno = lineno;
 	prep_stmt->connection = con;
-	prep_stmt->command = ecpg_strdup(stmt->command, lineno);
+	prep_stmt->command = ecpg_strdup(stmt->command, lineno, NULL);
+	if (!prep_stmt->command)
+	{
+		ecpg_free(prep_stmt);
+		ecpg_free(this);
+		return false;
+	}
 	prep_stmt->inlist = prep_stmt->outlist = NULL;
-	this->name = ecpg_strdup(stmt->name, lineno);
+	this->name = ecpg_strdup(stmt->name, lineno, NULL);
+	if (!this->name)
+	{
+		ecpg_free(prep_stmt->command);
+		ecpg_free(prep_stmt);
+		ecpg_free(this);
+		return false;
+	}
 	this->stmt = prep_stmt;
 	this->prepared = true;
 
@@ -177,14 +190,27 @@ prepare_common(int lineno, struct connection *con, const char *name, const char
 	/* create statement */
 	stmt->lineno = lineno;
 	stmt->connection = con;
-	stmt->command = ecpg_strdup(variable, lineno);
+	stmt->command = ecpg_strdup(variable, lineno, NULL);
+	if (!stmt->command)
+	{
+		ecpg_free(stmt);
+		ecpg_free(this);
+		return false;
+	}
 	stmt->inlist = stmt->outlist = NULL;
 
 	/* if we have C variables in our statement replace them with '?' */
 	replace_variables(&(stmt->command), lineno);
 
 	/* add prepared statement to our list */
-	this->name = ecpg_strdup(name, lineno);
+	this->name = ecpg_strdup(name, lineno, NULL);
+	if (!this->name)
+	{
+		ecpg_free(stmt->command);
+		ecpg_free(stmt);
+		ecpg_free(this);
+		return false;
+	}
 	this->stmt = stmt;
 
 	/* and finally really prepare the statement */
@@ -540,7 +566,9 @@ AddStmtToCache(int lineno,		/* line # of statement */
 	/* add the query to the entry */
 	entry = &stmtCacheEntries[entNo];
 	entry->lineno = lineno;
-	entry->ecpgQuery = ecpg_strdup(ecpgQuery, lineno);
+	entry->ecpgQuery = ecpg_strdup(ecpgQuery, lineno, NULL);
+	if (!entry->ecpgQuery)
+		return -1;
 	entry->connection = connection;
 	entry->execs = 0;
 	memcpy(entry->stmtID, stmtID, sizeof(entry->stmtID));
@@ -567,14 +595,19 @@ ecpg_auto_prepare(int lineno, const char *connection_name, const int compat, cha
 		ecpg_log("ecpg_auto_prepare on line %d: statement found in cache; entry %d\n", lineno, entNo);
 
 		stmtID = stmtCacheEntries[entNo].stmtID;
+		*name = ecpg_strdup(stmtID, lineno, NULL);
+		if (*name == NULL)
+			return false;
 
 		con = ecpg_get_connection(connection_name);
 		prep = ecpg_find_prepared_statement(stmtID, con, NULL);
 		/* This prepared name doesn't exist on this connection. */
 		if (!prep && !prepare_common(lineno, con, stmtID, query))
+		{
+			ecpg_free(*name);
 			return false;
+		}
 
-		*name = ecpg_strdup(stmtID, lineno);
 	}
 	else
 	{
@@ -584,15 +617,22 @@ ecpg_auto_prepare(int lineno, const char *connection_name, const int compat, cha
 
 		/* generate a statement ID */
 		sprintf(stmtID, "ecpg%d", nextStmtID++);
+		*name = ecpg_strdup(stmtID, lineno, NULL);
+		if (*name == NULL)
+			return false;
 
 		if (!ECPGprepare(lineno, connection_name, 0, stmtID, query))
+		{
+			ecpg_free(*name);
 			return false;
+		}
 
 		entNo = AddStmtToCache(lineno, stmtID, connection_name, compat, query);
 		if (entNo < 0)
+		{
+			ecpg_free(*name);
 			return false;
-
-		*name = ecpg_strdup(stmtID, lineno);
+		}
 	}
 
 	/* increase usage counter */
diff --git a/src/interfaces/libpq-oauth/Makefile b/src/interfaces/libpq-oauth/Makefile
index 270fc0cf2d9d9..682f17413b3a4 100644
--- a/src/interfaces/libpq-oauth/Makefile
+++ b/src/interfaces/libpq-oauth/Makefile
@@ -24,7 +24,7 @@ NAME = pq-oauth-$(MAJORVERSION)
 override shlib := lib$(NAME)$(DLSUFFIX)
 override stlib := libpq-oauth.a
 
-override CPPFLAGS := -I$(libpq_srcdir) -I$(top_builddir)/src/port $(LIBCURL_CPPFLAGS) $(CPPFLAGS)
+override CPPFLAGS := -I$(libpq_srcdir) -I$(top_builddir)/src/port $(CPPFLAGS) $(LIBCURL_CPPFLAGS)
 
 OBJS = \
 	$(WIN32RES)
diff --git a/src/interfaces/libpq/Makefile b/src/interfaces/libpq/Makefile
index 853aab4b1b886..da6650066d46e 100644
--- a/src/interfaces/libpq/Makefile
+++ b/src/interfaces/libpq/Makefile
@@ -24,7 +24,7 @@ NAME= pq
 SO_MAJOR_VERSION= 5
 SO_MINOR_VERSION= $(MAJORVERSION)
 
-override CPPFLAGS :=  -I$(srcdir) $(CPPFLAGS) -I$(top_builddir)/src/port -I$(top_srcdir)/src/port
+override CPPFLAGS := -I$(srcdir) -I$(top_builddir)/src/port -I$(top_srcdir)/src/port $(CPPFLAGS)
 ifneq ($(PORTNAME), win32)
 override CFLAGS += $(PTHREAD_CFLAGS)
 endif
@@ -87,7 +87,7 @@ endif
 # that are built correctly for use in a shlib.
 SHLIB_LINK_INTERNAL = -lpgcommon_shlib -lpgport_shlib
 ifneq ($(PORTNAME), win32)
-SHLIB_LINK += $(filter -lcrypt -ldes -lcom_err -lcrypto -lk5crypto -lkrb5 -lgssapi_krb5 -lgss -lgssapi -lssl -lsocket -lnsl -lresolv -lintl -lm, $(LIBS)) $(LDAP_LIBS_FE) $(PTHREAD_LIBS)
+SHLIB_LINK += $(filter -lcrypt -ldes -lcom_err -lcrypto -lk5crypto -lkrb5 -lgssapi_krb5 -lgss -lgssapi -lssl -lsocket -lnsl -lresolv -lintl -ldl -lm, $(LIBS)) $(LDAP_LIBS_FE) $(PTHREAD_LIBS)
 else
 SHLIB_LINK += $(filter -lcrypt -ldes -lcom_err -lcrypto -lk5crypto -lkrb5 -lgssapi32 -lssl -lsocket -lnsl -lresolv -lintl -lm $(PTHREAD_LIBS), $(LIBS)) $(LDAP_LIBS_FE)
 endif
diff --git a/src/interfaces/libpq/exports.txt b/src/interfaces/libpq/exports.txt
index 0625cf39e9af3..dbbae642d769a 100644
--- a/src/interfaces/libpq/exports.txt
+++ b/src/interfaces/libpq/exports.txt
@@ -205,9 +205,8 @@ PQcancelFinish            202
 PQsocketPoll              203
 PQsetChunkedRowsMode      204
 PQgetCurrentTimeUSec      205
-PQservice                 206
-PQsetAuthDataHook         207
-PQgetAuthDataHook         208
-PQdefaultAuthDataHook     209
-PQfullProtocolVersion     210
-appendPQExpBufferVA       211
+PQsetAuthDataHook         206
+PQgetAuthDataHook         207
+PQdefaultAuthDataHook     208
+PQfullProtocolVersion     209
+appendPQExpBufferVA       210
diff --git a/src/interfaces/libpq/fe-cancel.c b/src/interfaces/libpq/fe-cancel.c
index cd3102346bfa7..c872a0267f089 100644
--- a/src/interfaces/libpq/fe-cancel.c
+++ b/src/interfaces/libpq/fe-cancel.c
@@ -137,6 +137,7 @@ PQcancelCreate(PGconn *conn)
 		goto oom_error;
 
 	originalHost = conn->connhost[conn->whichhost];
+	cancelConn->connhost[0].type = originalHost.type;
 	if (originalHost.host)
 	{
 		cancelConn->connhost[0].host = strdup(originalHost.host);
@@ -378,7 +379,24 @@ PQgetCancel(PGconn *conn)
 
 	/* Check that we have received a cancellation key */
 	if (conn->be_cancel_key_len == 0)
-		return NULL;
+	{
+		/*
+		 * In case there is no cancel key, return an all-zero PGcancel object.
+		 * Actually calling PQcancel on this will fail, but we allow creating
+		 * the PGcancel object anyway. Arguably it would be better return NULL
+		 * to indicate that cancellation is not possible, but there'd be no
+		 * way for the caller to distinguish "out of memory" from "server did
+		 * not send a cancel key". Also, this is how PGgetCancel() has always
+		 * behaved, and if we changed it, some clients would stop working
+		 * altogether with servers that don't support cancellation. (The
+		 * modern PQcancelCreate() function returns a failed connection object
+		 * instead.)
+		 *
+		 * The returned dummy object has cancel_pkt_len == 0; we check for
+		 * that in PQcancel() to identify it as a dummy.
+		 */
+		return calloc(1, sizeof(PGcancel));
+	}
 
 	cancel_req_len = offsetof(CancelRequestPacket, cancelAuthCode) + conn->be_cancel_key_len;
 	cancel = malloc(offsetof(PGcancel, cancel_req) + cancel_req_len);
@@ -543,6 +561,15 @@ PQcancel(PGcancel *cancel, char *errbuf, int errbufsize)
 		return false;
 	}
 
+	if (cancel->cancel_pkt_len == 0)
+	{
+		/* This is a dummy PGcancel object, see PQgetCancel */
+		strlcpy(errbuf, "PQcancel() -- no cancellation key received", errbufsize);
+		/* strlcpy probably doesn't change errno, but be paranoid */
+		SOCK_ERRNO_SET(save_errno);
+		return false;
+	}
+
 	/*
 	 * We need to open a temporary connection to the postmaster. Do this with
 	 * only kernel calls.
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 51a9c41658455..afa85d9fca961 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -201,6 +201,10 @@ static const internalPQconninfoOption PQconninfoOptions[] = {
 		"Database-Service", "", 20,
 	offsetof(struct pg_conn, pgservice)},
 
+	{"servicefile", "PGSERVICEFILE", NULL, NULL,
+		"Database-Service-File", "", 64,
+	offsetof(struct pg_conn, pgservicefile)},
+
 	{"user", "PGUSER", NULL, NULL,
 		"Database-User", "", 20,
 	offsetof(struct pg_conn, pguser)},
@@ -5062,6 +5066,7 @@ freePGconn(PGconn *conn)
 	free(conn->dbName);
 	free(conn->replication);
 	free(conn->pgservice);
+	free(conn->pgservicefile);
 	free(conn->pguser);
 	if (conn->pgpass)
 	{
@@ -5914,6 +5919,7 @@ static int
 parseServiceInfo(PQconninfoOption *options, PQExpBuffer errorMessage)
 {
 	const char *service = conninfo_getval(options, "service");
+	const char *service_fname = conninfo_getval(options, "servicefile");
 	char		serviceFile[MAXPGPATH];
 	char	   *env;
 	bool		group_found = false;
@@ -5933,10 +5939,13 @@ parseServiceInfo(PQconninfoOption *options, PQExpBuffer errorMessage)
 		return 0;
 
 	/*
-	 * Try PGSERVICEFILE if specified, else try ~/.pg_service.conf (if that
-	 * exists).
+	 * First, try the "servicefile" option in connection string.  Then, try
+	 * the PGSERVICEFILE environment variable.  Finally, check
+	 * ~/.pg_service.conf (if that exists).
 	 */
-	if ((env = getenv("PGSERVICEFILE")) != NULL)
+	if (service_fname != NULL)
+		strlcpy(serviceFile, service_fname, sizeof(serviceFile));
+	else if ((env = getenv("PGSERVICEFILE")) != NULL)
 		strlcpy(serviceFile, env, sizeof(serviceFile));
 	else
 	{
@@ -6092,7 +6101,17 @@ parseServiceFile(const char *serviceFile,
 				if (strcmp(key, "service") == 0)
 				{
 					libpq_append_error(errorMessage,
-									   "nested service specifications not supported in service file \"%s\", line %d",
+									   "nested \"service\" specifications not supported in service file \"%s\", line %d",
+									   serviceFile,
+									   linenr);
+					result = 3;
+					goto exit;
+				}
+
+				if (strcmp(key, "servicefile") == 0)
+				{
+					libpq_append_error(errorMessage,
+									   "nested \"servicefile\" specifications not supported in service file \"%s\", line %d",
 									   serviceFile,
 									   linenr);
 					result = 3;
@@ -6135,6 +6154,33 @@ parseServiceFile(const char *serviceFile,
 	}
 
 exit:
+
+	/*
+	 * If a service has been successfully found, set the "servicefile" option
+	 * if not already set.  This matters when we use a default service file or
+	 * PGSERVICEFILE, where we want to be able track the value.
+	 */
+	if (*group_found && result == 0)
+	{
+		for (i = 0; options[i].keyword; i++)
+		{
+			if (strcmp(options[i].keyword, "servicefile") != 0)
+				continue;
+
+			/* If value is already set, nothing to do */
+			if (options[i].val != NULL)
+				break;
+
+			options[i].val = strdup(serviceFile);
+			if (options[i].val == NULL)
+			{
+				libpq_append_error(errorMessage, "out of memory");
+				result = 3;
+			}
+			break;
+		}
+	}
+
 	fclose(f);
 
 	return result;
@@ -7461,14 +7507,6 @@ PQdb(const PGconn *conn)
 	return conn->dbName;
 }
 
-char *
-PQservice(const PGconn *conn)
-{
-	if (!conn)
-		return NULL;
-	return conn->pgservice;
-}
-
 char *
 PQuser(const PGconn *conn)
 {
@@ -7536,10 +7574,12 @@ PQport(const PGconn *conn)
 	if (!conn)
 		return NULL;
 
-	if (conn->connhost != NULL)
+	if (conn->connhost != NULL &&
+		conn->connhost[conn->whichhost].port != NULL &&
+		conn->connhost[conn->whichhost].port[0] != '\0')
 		return conn->connhost[conn->whichhost].port;
 
-	return "";
+	return DEF_PGPORT_STR;
 }
 
 /*
diff --git a/src/interfaces/libpq/fe-secure-openssl.c b/src/interfaces/libpq/fe-secure-openssl.c
index b08b3a6901b77..51dd7b9fec0ab 100644
--- a/src/interfaces/libpq/fe-secure-openssl.c
+++ b/src/interfaces/libpq/fe-secure-openssl.c
@@ -693,34 +693,35 @@ static unsigned char alpn_protos[] = PG_ALPN_PROTOCOL_VECTOR;
  * purposes.  The file will be written using the NSS keylog format.  LibreSSL
  * 3.5 introduced stub function to set the callback for OpenSSL compatibility
  * but the callback is never invoked.
+ *
+ * Error messages added to the connection object wont be printed anywhere if
+ * the connection is successful.  Errors in processing keylogging are printed
+ * to stderr to overcome this.
  */
 static void
 SSL_CTX_keylog_cb(const SSL *ssl, const char *line)
 {
 	int			fd;
-	mode_t		old_umask;
 	ssize_t		rc;
 	PGconn	   *conn = SSL_get_app_data(ssl);
 
 	if (conn == NULL)
 		return;
 
-	old_umask = umask(077);
 	fd = open(conn->sslkeylogfile, O_WRONLY | O_APPEND | O_CREAT, 0600);
-	umask(old_umask);
 
 	if (fd == -1)
 	{
-		libpq_append_conn_error(conn, "could not open SSL key logging file \"%s\": %s",
-								conn->sslkeylogfile, pg_strerror(errno));
+		fprintf(stderr, libpq_gettext("WARNING: could not open SSL key logging file \"%s\": %m\n"),
+				conn->sslkeylogfile);
 		return;
 	}
 
 	/* line is guaranteed by OpenSSL to be NUL terminated */
 	rc = write(fd, line, strlen(line));
 	if (rc < 0)
-		libpq_append_conn_error(conn, "could not write to SSL key logging file \"%s\": %s",
-								conn->sslkeylogfile, pg_strerror(errno));
+		fprintf(stderr, libpq_gettext("WARNING: could not write to SSL key logging file \"%s\": %m\n"),
+				conn->sslkeylogfile);
 	else
 		rc = write(fd, "\n", 1);
 	(void) rc;					/* silence compiler warnings */
@@ -1044,6 +1045,10 @@ initialize_SSL(PGconn *conn)
 	}
 	conn->ssl_in_use = true;
 
+	/*
+	 * If SSL key logging is requested, set up the callback if a compatible
+	 * version of OpenSSL is used and libpq was compiled to support it.
+	 */
 	if (conn->sslkeylogfile && strlen(conn->sslkeylogfile) > 0)
 	{
 #ifdef HAVE_SSL_CTX_SET_KEYLOG_CALLBACK
@@ -1057,7 +1062,6 @@ initialize_SSL(PGconn *conn)
 #endif
 	}
 
-
 	/*
 	 * SSL contexts are reference counted by OpenSSL. We can free it as soon
 	 * as we have created the SSL object, and it will stick around for as long
diff --git a/src/interfaces/libpq/libpq-fe.h b/src/interfaces/libpq/libpq-fe.h
index 7d3a9df6fd559..af8004f952a56 100644
--- a/src/interfaces/libpq/libpq-fe.h
+++ b/src/interfaces/libpq/libpq-fe.h
@@ -400,7 +400,6 @@ extern int	PQrequestCancel(PGconn *conn);
 
 /* Accessor functions for PGconn objects */
 extern char *PQdb(const PGconn *conn);
-extern char *PQservice(const PGconn *conn);
 extern char *PQuser(const PGconn *conn);
 extern char *PQpass(const PGconn *conn);
 extern char *PQhost(const PGconn *conn);
diff --git a/src/interfaces/libpq/libpq-int.h b/src/interfaces/libpq/libpq-int.h
index a6cfd7f5c9d83..a701c25038a75 100644
--- a/src/interfaces/libpq/libpq-int.h
+++ b/src/interfaces/libpq/libpq-int.h
@@ -357,7 +357,8 @@ typedef struct pg_conn_host
 	pg_conn_host_type type;		/* type of host address */
 	char	   *host;			/* host name or socket path */
 	char	   *hostaddr;		/* host numeric IP address */
-	char	   *port;			/* port number (always provided) */
+	char	   *port;			/* port number (if NULL or empty, use
+								 * DEF_PGPORT[_STR]) */
 	char	   *password;		/* password for this host, read from the
 								 * password file; NULL if not sought or not
 								 * found in password file. */
@@ -389,6 +390,8 @@ struct pg_conn
 	char	   *dbName;			/* database name */
 	char	   *replication;	/* connect as the replication standby? */
 	char	   *pgservice;		/* Postgres service, if any */
+	char	   *pgservicefile;	/* path to a service file containing
+								 * service(s) */
 	char	   *pguser;			/* Postgres username and password, if any */
 	char	   *pgpass;
 	char	   *pgpassfile;		/* path to a file containing password(s) */
diff --git a/src/interfaces/libpq/t/006_service.pl b/src/interfaces/libpq/t/006_service.pl
index 4fe5adc5c2acd..797e6232b8fcb 100644
--- a/src/interfaces/libpq/t/006_service.pl
+++ b/src/interfaces/libpq/t/006_service.pl
@@ -47,6 +47,19 @@
 # Missing service file.
 my $srvfile_missing = "$td/pg_service_missing.conf";
 
+# Service file with nested "service" defined.
+my $srvfile_nested = "$td/pg_service_nested.conf";
+copy($srvfile_valid, $srvfile_nested)
+  or die "Could not copy $srvfile_valid to $srvfile_nested: $!";
+append_to_file($srvfile_nested, 'service=invalid_srv' . $newline);
+
+# Service file with nested "servicefile" defined.
+my $srvfile_nested_2 = "$td/pg_service_nested_2.conf";
+copy($srvfile_valid, $srvfile_nested_2)
+  or die "Could not copy $srvfile_valid to $srvfile_nested_2: $!";
+append_to_file($srvfile_nested_2,
+	'servicefile=' . $srvfile_default . $newline);
+
 # Set the fallback directory lookup of the service file to the temporary
 # directory of this test.  PGSYSCONFDIR is used if the service file
 # defined in PGSERVICEFILE cannot be found, or when a service file is
@@ -146,6 +159,85 @@
 	unlink($srvfile_default);
 }
 
+# Checks nested service file contents.
+{
+	local $ENV{PGSERVICEFILE} = $srvfile_nested;
+
+	$dummy_node->connect_fails(
+		'service=my_srv',
+		'connection with "service" in nested service file',
+		expected_stderr =>
+		  qr/nested "service" specifications not supported in service file/);
+
+	local $ENV{PGSERVICEFILE} = $srvfile_nested_2;
+
+	$dummy_node->connect_fails(
+		'service=my_srv',
+		'connection with "servicefile" in nested service file',
+		expected_stderr =>
+		  qr/nested "servicefile" specifications not supported in service file/
+	);
+}
+
+# Properly escape backslashes in the path, to ensure the generation of
+# correct connection strings.
+my $srvfile_win_cared = $srvfile_valid;
+$srvfile_win_cared =~ s/\\/\\\\/g;
+
+# Checks that the "servicefile" option works as expected
+{
+	$dummy_node->connect_ok(
+		q{service=my_srv servicefile='} . $srvfile_win_cared . q{'},
+		'connection with valid servicefile in connection string',
+		sql => "SELECT 'connect3_1'",
+		expected_stdout => qr/connect3_1/);
+
+	# Encode slashes and backslash
+	my $encoded_srvfile = $srvfile_valid =~ s{([\\/])}{
+		$1 eq '/' ? '%2F' : '%5C'
+	}ger;
+
+	# Additionally encode a colon in servicefile path of Windows
+	$encoded_srvfile =~ s/:/%3A/g;
+
+	$dummy_node->connect_ok(
+		'postgresql:///?service=my_srv&servicefile=' . $encoded_srvfile,
+		'connection with valid servicefile in URI',
+		sql => "SELECT 'connect3_2'",
+		expected_stdout => qr/connect3_2/);
+
+	local $ENV{PGSERVICE} = 'my_srv';
+	$dummy_node->connect_ok(
+		q{servicefile='} . $srvfile_win_cared . q{'},
+		'connection with PGSERVICE and servicefile in connection string',
+		sql => "SELECT 'connect3_3'",
+		expected_stdout => qr/connect3_3/);
+
+	$dummy_node->connect_ok(
+		'postgresql://?servicefile=' . $encoded_srvfile,
+		'connection with PGSERVICE and servicefile in URI',
+		sql => "SELECT 'connect3_4'",
+		expected_stdout => qr/connect3_4/);
+}
+
+# Check that the "servicefile" option takes priority over the PGSERVICEFILE
+# environment variable.
+{
+	local $ENV{PGSERVICEFILE} = 'non-existent-file.conf';
+
+	$dummy_node->connect_fails(
+		'service=my_srv',
+		'connection with invalid PGSERVICEFILE',
+		expected_stderr =>
+		  qr/service file "non-existent-file\.conf" not found/);
+
+	$dummy_node->connect_ok(
+		q{service=my_srv servicefile='} . $srvfile_win_cared . q{'},
+		'connection with both servicefile and PGSERVICEFILE',
+		sql => "SELECT 'connect4_1'",
+		expected_stdout => qr/connect4_1/);
+}
+
 $node->teardown_node;
 
 done_testing();
diff --git a/src/makefiles/meson.build b/src/makefiles/meson.build
index 91a8de1ee9b9d..54dbc059adac7 100644
--- a/src/makefiles/meson.build
+++ b/src/makefiles/meson.build
@@ -6,7 +6,7 @@
 
 # Emulation of PGAC_CHECK_STRIP
 strip_bin = find_program(get_option('STRIP'), required: false, native: true)
-strip_cmd = strip_bin.found() ? [strip_bin.path()] : [':']
+strip_cmd = strip_bin.found() ? [strip_bin.full_path()] : [':']
 
 working_strip = false
 if strip_bin.found()
@@ -49,8 +49,8 @@ pgxs_kv = {
   'PORTNAME': portname,
   'PG_SYSROOT': pg_sysroot,
 
-  'abs_top_builddir': meson.build_root(),
-  'abs_top_srcdir': meson.source_root(),
+  'abs_top_builddir': meson.project_build_root(),
+  'abs_top_srcdir': meson.project_source_root(),
 
   'enable_rpath': get_option('rpath') ? 'yes' : 'no',
   'enable_nls': libintl.found() ? 'yes' : 'no',
@@ -123,7 +123,7 @@ pgxs_kv = {
 
 if llvm.found()
   pgxs_kv += {
-    'CLANG': clang.path(),
+    'CLANG': clang.full_path(),
     'CXX': ' '.join(cpp.cmd_array()),
     'LLVM_BINPATH': llvm_binpath,
   }
@@ -258,7 +258,7 @@ pgxs_deps = {
 pgxs_cdata = configuration_data(pgxs_kv)
 
 foreach b, p : pgxs_bins
-  pgxs_cdata.set(b, p.found() ? p.path() : '')
+  pgxs_cdata.set(b, p.found() ? p.full_path() : '')
 endforeach
 
 foreach pe : pgxs_empty
diff --git a/src/pl/plperl/meson.build b/src/pl/plperl/meson.build
index b463d4d56c5b3..7c4081c3460e0 100644
--- a/src/pl/plperl/meson.build
+++ b/src/pl/plperl/meson.build
@@ -96,7 +96,7 @@ tests += {
       'plperl_transaction',
       'plperl_env',
     ],
-    'regress_args': ['--dlpath', meson.build_root() / 'src/test/regress'],
+    'regress_args': ['--dlpath', meson.project_build_root() / 'src/test/regress'],
   },
 }
 
diff --git a/src/pl/plpgsql/src/expected/plpgsql_misc.out b/src/pl/plpgsql/src/expected/plpgsql_misc.out
index a6511df08ec9f..ffb377f5f54ff 100644
--- a/src/pl/plpgsql/src/expected/plpgsql_misc.out
+++ b/src/pl/plpgsql/src/expected/plpgsql_misc.out
@@ -65,3 +65,39 @@ do $$ declare x public.foo%rowtype; begin end $$;
 ERROR:  relation "public.foo" does not exist
 CONTEXT:  compilation of PL/pgSQL function "inline_code_block" near line 1
 do $$ declare x public.misc_table%rowtype; begin end $$;
+-- Test handling of an unreserved keyword as a variable name
+-- and record field name.
+do $$
+declare
+  execute int;
+  r record;
+begin
+  execute := 10;
+  raise notice 'execute = %', execute;
+  select 1 as strict into r;
+  raise notice 'r.strict = %', r.strict;
+end $$;
+NOTICE:  execute = 10
+NOTICE:  r.strict = 1
+-- Test handling of a reserved keyword as a record field name.
+do $$ declare r record;
+begin
+  select 1 as x, 2 as foreach into r;
+  raise notice 'r.x = %', r.x;
+  raise notice 'r.foreach = %', r.foreach;  -- fails
+end $$;
+NOTICE:  r.x = 1
+ERROR:  field name "foreach" is a reserved key word
+LINE 1: r.foreach
+        ^
+HINT:  Use double quotes to quote it.
+QUERY:  r.foreach
+CONTEXT:  PL/pgSQL function inline_code_block line 5 at RAISE
+do $$ declare r record;
+begin
+  select 1 as x, 2 as foreach into r;
+  raise notice 'r.x = %', r.x;
+  raise notice 'r."foreach" = %', r."foreach";  -- ok
+end $$;
+NOTICE:  r.x = 1
+NOTICE:  r."foreach" = 2
diff --git a/src/pl/plpgsql/src/pl_comp.c b/src/pl/plpgsql/src/pl_comp.c
index b80c59447fb57..f6976689a6927 100644
--- a/src/pl/plpgsql/src/pl_comp.c
+++ b/src/pl/plpgsql/src/pl_comp.c
@@ -177,6 +177,7 @@ plpgsql_compile_callback(FunctionCallInfo fcinfo,
 	yyscan_t	scanner;
 	Datum		prosrcdatum;
 	char	   *proc_source;
+	char	   *proc_signature;
 	HeapTuple	typeTup;
 	Form_pg_type typeStruct;
 	PLpgSQL_variable *var;
@@ -223,6 +224,9 @@ plpgsql_compile_callback(FunctionCallInfo fcinfo,
 	plpgsql_check_syntax = forValidator;
 	plpgsql_curr_compile = function;
 
+	/* format_procedure leaks memory, so run it in temp context */
+	proc_signature = format_procedure(fcinfo->flinfo->fn_oid);
+
 	/*
 	 * All the permanent output of compilation (e.g. parse tree) is kept in a
 	 * per-function memory context, so it can be reclaimed easily.
@@ -237,7 +241,7 @@ plpgsql_compile_callback(FunctionCallInfo fcinfo,
 									 ALLOCSET_DEFAULT_SIZES);
 	plpgsql_compile_tmp_cxt = MemoryContextSwitchTo(func_cxt);
 
-	function->fn_signature = format_procedure(fcinfo->flinfo->fn_oid);
+	function->fn_signature = pstrdup(proc_signature);
 	MemoryContextSetIdentifier(func_cxt, function->fn_signature);
 	function->fn_oid = fcinfo->flinfo->fn_oid;
 	function->fn_input_collation = fcinfo->fncollation;
@@ -1211,17 +1215,22 @@ resolve_column_ref(ParseState *pstate, PLpgSQL_expr *expr,
 				}
 
 				/*
-				 * We should not get here, because a RECFIELD datum should
-				 * have been built at parse time for every possible qualified
-				 * reference to fields of this record.  But if we do, handle
-				 * it like field-not-found: throw error or return NULL.
+				 * Ideally we'd never get here, because a RECFIELD datum
+				 * should have been built at parse time for every qualified
+				 * reference to a field of this record that appears in the
+				 * source text.  However, plpgsql_yylex will not build such a
+				 * datum unless the field name lexes as token type IDENT.
+				 * Hence, if the would-be field name is a PL/pgSQL reserved
+				 * word, we lose.  Assume that that's what happened and tell
+				 * the user to quote it, unless the caller prefers we just
+				 * return NULL.
 				 */
 				if (error_if_no_field)
 					ereport(ERROR,
-							(errcode(ERRCODE_UNDEFINED_COLUMN),
-							 errmsg("record \"%s\" has no field \"%s\"",
-									(nnames_field == 1) ? name1 : name2,
+							(errcode(ERRCODE_SYNTAX_ERROR),
+							 errmsg("field name \"%s\" is a reserved key word",
 									colname),
+							 errhint("Use double quotes to quote it."),
 							 parser_errposition(pstate, cref->location)));
 			}
 			break;
@@ -1668,6 +1677,11 @@ plpgsql_parse_wordrowtype(char *ident)
 {
 	Oid			classOid;
 	Oid			typOid;
+	TypeName   *typName;
+	MemoryContext oldCxt;
+
+	/* Avoid memory leaks in long-term function context */
+	oldCxt = MemoryContextSwitchTo(plpgsql_compile_tmp_cxt);
 
 	/*
 	 * Look up the relation.  Note that because relation rowtypes have the
@@ -1690,9 +1704,12 @@ plpgsql_parse_wordrowtype(char *ident)
 				 errmsg("relation \"%s\" does not have a composite type",
 						ident)));
 
+	typName = makeTypeName(ident);
+
+	MemoryContextSwitchTo(oldCxt);
+
 	/* Build and return the row type struct */
-	return plpgsql_build_datatype(typOid, -1, InvalidOid,
-								  makeTypeName(ident));
+	return plpgsql_build_datatype(typOid, -1, InvalidOid, typName);
 }
 
 /* ----------
@@ -1706,6 +1723,7 @@ plpgsql_parse_cwordrowtype(List *idents)
 	Oid			classOid;
 	Oid			typOid;
 	RangeVar   *relvar;
+	TypeName   *typName;
 	MemoryContext oldCxt;
 
 	/*
@@ -1728,11 +1746,12 @@ plpgsql_parse_cwordrowtype(List *idents)
 				 errmsg("relation \"%s\" does not have a composite type",
 						relvar->relname)));
 
+	typName = makeTypeNameFromNameList(idents);
+
 	MemoryContextSwitchTo(oldCxt);
 
 	/* Build and return the row type struct */
-	return plpgsql_build_datatype(typOid, -1, InvalidOid,
-								  makeTypeNameFromNameList(idents));
+	return plpgsql_build_datatype(typOid, -1, InvalidOid, typName);
 }
 
 /*
@@ -1947,6 +1966,8 @@ plpgsql_build_recfield(PLpgSQL_rec *rec, const char *fldname)
  * origtypname is the parsed form of what the user wrote as the type name.
  * It can be NULL if the type could not be a composite type, or if it was
  * identified by OID to begin with (e.g., it's a function argument type).
+ * origtypname is in short-lived storage and must be copied if we choose
+ * to incorporate it into the function's parse tree.
  */
 PLpgSQL_type *
 plpgsql_build_datatype(Oid typeOid, int32 typmod,
@@ -2065,7 +2086,7 @@ build_datatype(HeapTuple typeTup, int32 typmod,
 					 errmsg("type %s is not composite",
 							format_type_be(typ->typoid))));
 
-		typ->origtypname = origtypname;
+		typ->origtypname = copyObject(origtypname);
 		typ->tcache = typentry;
 		typ->tupdesc_id = typentry->tupDesc_identifier;
 	}
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index bb99781c56e39..d19425b7a71ae 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -5703,7 +5703,7 @@ exec_eval_expr(PLpgSQL_execstate *estate,
 	/*
 	 * Else do it the hard way via exec_run_select
 	 */
-	rc = exec_run_select(estate, expr, 2, NULL);
+	rc = exec_run_select(estate, expr, 0, NULL);
 	if (rc != SPI_OK_SELECT)
 		ereport(ERROR,
 				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
@@ -5757,6 +5757,10 @@ exec_eval_expr(PLpgSQL_execstate *estate,
 
 /* ----------
  * exec_run_select			Execute a select query
+ *
+ * Note: passing maxtuples different from 0 ("return all tuples") is
+ * deprecated because it will prevent parallel execution of the query.
+ * However, we retain the parameter in case we need it someday.
  * ----------
  */
 static int
@@ -8606,6 +8610,15 @@ exec_set_found(PLpgSQL_execstate *estate, bool state)
 	PLpgSQL_var *var;
 
 	var = (PLpgSQL_var *) (estate->datums[estate->found_varno]);
+
+	/*
+	 * Use pg_assume() to avoid a spurious warning with some compilers, by
+	 * telling the compiler that the VARATT_IS_EXTERNAL_NON_EXPANDED() branch
+	 * in assign_simple_var() will never be reached when called from here, due
+	 * to "found" being a boolean (i.e. a byvalue type), not a varlena.
+	 */
+	pg_assume(var->datatype->typlen != -1);
+
 	assign_simple_var(estate, var, BoolGetDatum(state), false, false);
 }
 
diff --git a/src/pl/plpgsql/src/pl_gram.y b/src/pl/plpgsql/src/pl_gram.y
index 5612e66d0239d..17568d82554d2 100644
--- a/src/pl/plpgsql/src/pl_gram.y
+++ b/src/pl/plpgsql/src/pl_gram.y
@@ -1368,7 +1368,8 @@ for_control		: for_variable K_IN
 						int			tok = yylex(&yylval, &yylloc, yyscanner);
 						int			tokloc = yylloc;
 
-						if (tok == K_EXECUTE)
+						if (tok_is_keyword(tok, &yylval,
+										   K_EXECUTE, "execute"))
 						{
 							/* EXECUTE means it's a dynamic FOR loop */
 							PLpgSQL_stmt_dynfors *new;
@@ -2135,7 +2136,8 @@ stmt_open		: K_OPEN cursor_variable
 								yyerror(&yylloc, NULL, yyscanner, "syntax error, expected \"FOR\"");
 
 							tok = yylex(&yylval, &yylloc, yyscanner);
-							if (tok == K_EXECUTE)
+							if (tok_is_keyword(tok, &yylval,
+											   K_EXECUTE, "execute"))
 							{
 								int			endtoken;
 
@@ -2536,6 +2538,7 @@ unreserved_keyword	:
 				| K_ERRCODE
 				| K_ERROR
 				| K_EXCEPTION
+				| K_EXECUTE
 				| K_EXIT
 				| K_FETCH
 				| K_FIRST
@@ -2581,6 +2584,7 @@ unreserved_keyword	:
 				| K_SLICE
 				| K_SQLSTATE
 				| K_STACKED
+				| K_STRICT
 				| K_TABLE
 				| K_TABLE_NAME
 				| K_TYPE
@@ -3514,7 +3518,8 @@ make_return_query_stmt(int location, YYSTYPE *yylvalp, YYLTYPE *yyllocp, yyscan_
 	new->stmtid = ++plpgsql_curr_compile->nstatements;
 
 	/* check for RETURN QUERY EXECUTE */
-	if ((tok = yylex(yylvalp, yyllocp, yyscanner)) != K_EXECUTE)
+	tok = yylex(yylvalp, yyllocp, yyscanner);
+	if (!tok_is_keyword(tok, yylvalp, K_EXECUTE, "execute"))
 	{
 		/* ordinary static query */
 		plpgsql_push_back_token(tok, yylvalp, yyllocp, yyscanner);
@@ -3597,7 +3602,7 @@ read_into_target(PLpgSQL_variable **target, bool *strict, YYSTYPE *yylvalp, YYLT
 		*strict = false;
 
 	tok = yylex(yylvalp, yyllocp, yyscanner);
-	if (strict && tok == K_STRICT)
+	if (strict && tok_is_keyword(tok, yylvalp, K_STRICT, "strict"))
 	{
 		*strict = true;
 		tok = yylex(yylvalp, yyllocp, yyscanner);
@@ -3848,6 +3853,7 @@ parse_datatype(const char *string, int location, yyscan_t yyscanner)
 	int32		typmod;
 	sql_error_callback_arg cbarg;
 	ErrorContextCallback syntax_errcontext;
+	MemoryContext oldCxt;
 
 	cbarg.location = location;
 	cbarg.yyscanner = yyscanner;
@@ -3857,9 +3863,14 @@ parse_datatype(const char *string, int location, yyscan_t yyscanner)
 	syntax_errcontext.previous = error_context_stack;
 	error_context_stack = &syntax_errcontext;
 
-	/* Let the main parser try to parse it under standard SQL rules */
+	/*
+	 * Let the main parser try to parse it under standard SQL rules.  The
+	 * parser leaks memory, so run it in temp context.
+	 */
+	oldCxt = MemoryContextSwitchTo(plpgsql_compile_tmp_cxt);
 	typeName = typeStringToTypeName(string, NULL);
 	typenameTypeIdAndMod(NULL, typeName, &type_id, &typmod);
+	MemoryContextSwitchTo(oldCxt);
 
 	/* Restore former ereport callback */
 	error_context_stack = syntax_errcontext.previous;
diff --git a/src/pl/plpgsql/src/pl_reserved_kwlist.h b/src/pl/plpgsql/src/pl_reserved_kwlist.h
index ce7b0c9d33121..f3ef2cbd8d7dc 100644
--- a/src/pl/plpgsql/src/pl_reserved_kwlist.h
+++ b/src/pl/plpgsql/src/pl_reserved_kwlist.h
@@ -33,7 +33,6 @@ PG_KEYWORD("case", K_CASE)
 PG_KEYWORD("declare", K_DECLARE)
 PG_KEYWORD("else", K_ELSE)
 PG_KEYWORD("end", K_END)
-PG_KEYWORD("execute", K_EXECUTE)
 PG_KEYWORD("for", K_FOR)
 PG_KEYWORD("foreach", K_FOREACH)
 PG_KEYWORD("from", K_FROM)
@@ -44,7 +43,6 @@ PG_KEYWORD("loop", K_LOOP)
 PG_KEYWORD("not", K_NOT)
 PG_KEYWORD("null", K_NULL)
 PG_KEYWORD("or", K_OR)
-PG_KEYWORD("strict", K_STRICT)
 PG_KEYWORD("then", K_THEN)
 PG_KEYWORD("to", K_TO)
 PG_KEYWORD("using", K_USING)
diff --git a/src/pl/plpgsql/src/pl_scanner.c b/src/pl/plpgsql/src/pl_scanner.c
index d08187dafcb4c..19825e5c71810 100644
--- a/src/pl/plpgsql/src/pl_scanner.c
+++ b/src/pl/plpgsql/src/pl_scanner.c
@@ -53,7 +53,7 @@ IdentifierLookup plpgsql_IdentifierLookup = IDENTIFIER_LOOKUP_NORMAL;
  * We try to avoid reserving more keywords than we have to; but there's
  * little point in not reserving a word if it's reserved in the core grammar.
  * Currently, the following words are reserved here but not in the core:
- * BEGIN BY DECLARE EXECUTE FOREACH IF LOOP STRICT WHILE
+ * BEGIN BY DECLARE FOREACH IF LOOP WHILE
  */
 
 /* ScanKeywordList lookup data for PL/pgSQL keywords */
diff --git a/src/pl/plpgsql/src/pl_unreserved_kwlist.h b/src/pl/plpgsql/src/pl_unreserved_kwlist.h
index 98f99ec470cf4..b48c5a645ffaf 100644
--- a/src/pl/plpgsql/src/pl_unreserved_kwlist.h
+++ b/src/pl/plpgsql/src/pl_unreserved_kwlist.h
@@ -58,6 +58,7 @@ PG_KEYWORD("elsif", K_ELSIF)
 PG_KEYWORD("errcode", K_ERRCODE)
 PG_KEYWORD("error", K_ERROR)
 PG_KEYWORD("exception", K_EXCEPTION)
+PG_KEYWORD("execute", K_EXECUTE)
 PG_KEYWORD("exit", K_EXIT)
 PG_KEYWORD("fetch", K_FETCH)
 PG_KEYWORD("first", K_FIRST)
@@ -103,6 +104,7 @@ PG_KEYWORD("scroll", K_SCROLL)
 PG_KEYWORD("slice", K_SLICE)
 PG_KEYWORD("sqlstate", K_SQLSTATE)
 PG_KEYWORD("stacked", K_STACKED)
+PG_KEYWORD("strict", K_STRICT)
 PG_KEYWORD("table", K_TABLE)
 PG_KEYWORD("table_name", K_TABLE_NAME)
 PG_KEYWORD("type", K_TYPE)
diff --git a/src/pl/plpgsql/src/sql/plpgsql_misc.sql b/src/pl/plpgsql/src/sql/plpgsql_misc.sql
index d3a7f703a758d..0bc39fcf3257c 100644
--- a/src/pl/plpgsql/src/sql/plpgsql_misc.sql
+++ b/src/pl/plpgsql/src/sql/plpgsql_misc.sql
@@ -37,3 +37,32 @@ do $$ declare x foo.bar%rowtype; begin end $$;
 do $$ declare x foo.bar.baz%rowtype; begin end $$;
 do $$ declare x public.foo%rowtype; begin end $$;
 do $$ declare x public.misc_table%rowtype; begin end $$;
+
+-- Test handling of an unreserved keyword as a variable name
+-- and record field name.
+do $$
+declare
+  execute int;
+  r record;
+begin
+  execute := 10;
+  raise notice 'execute = %', execute;
+  select 1 as strict into r;
+  raise notice 'r.strict = %', r.strict;
+end $$;
+
+-- Test handling of a reserved keyword as a record field name.
+
+do $$ declare r record;
+begin
+  select 1 as x, 2 as foreach into r;
+  raise notice 'r.x = %', r.x;
+  raise notice 'r.foreach = %', r.foreach;  -- fails
+end $$;
+
+do $$ declare r record;
+begin
+  select 1 as x, 2 as foreach into r;
+  raise notice 'r.x = %', r.x;
+  raise notice 'r."foreach" = %', r."foreach";  -- ok
+end $$;
diff --git a/src/pl/plpython/Makefile b/src/pl/plpython/Makefile
index f959083a0bdec..25f295c3709e2 100644
--- a/src/pl/plpython/Makefile
+++ b/src/pl/plpython/Makefile
@@ -11,7 +11,7 @@ ifeq ($(PORTNAME), win32)
 override python_libspec =
 endif
 
-override CPPFLAGS := -I. -I$(srcdir) $(python_includespec) $(CPPFLAGS)
+override CPPFLAGS := -I. -I$(srcdir) $(CPPFLAGS) $(python_includespec)
 
 rpathdir = $(python_libdir)
 
diff --git a/src/pl/tcl/Makefile b/src/pl/tcl/Makefile
index ea52a2efc229d..dd57f7d694c82 100644
--- a/src/pl/tcl/Makefile
+++ b/src/pl/tcl/Makefile
@@ -11,7 +11,7 @@ top_builddir = ../../..
 include $(top_builddir)/src/Makefile.global
 
 
-override CPPFLAGS := -I. -I$(srcdir) $(TCL_INCLUDE_SPEC) $(CPPFLAGS)
+override CPPFLAGS := -I. -I$(srcdir) $(CPPFLAGS) $(TCL_INCLUDE_SPEC)
 
 # On Windows, we don't link directly with the Tcl library; see below
 ifneq ($(PORTNAME), win32)
diff --git a/src/port/pg_numa.c b/src/port/pg_numa.c
index 4b487a2a4e814..3368a43a33826 100644
--- a/src/port/pg_numa.c
+++ b/src/port/pg_numa.c
@@ -16,6 +16,7 @@
 #include "c.h"
 #include <unistd.h>
 
+#include "miscadmin.h"
 #include "port/pg_numa.h"
 
 /*
@@ -29,6 +30,19 @@
 #include <numa.h>
 #include <numaif.h>
 
+/*
+ * numa_move_pages() chunk size, has to be <= 16 to work around a kernel bug
+ * in do_pages_stat() (chunked by DO_PAGES_STAT_CHUNK_NR). By using the same
+ * chunk size, we make it work even on unfixed kernels.
+ *
+ * 64-bit system are not affected by the bug, and so use much larger chunks.
+ */
+#if SIZEOF_SIZE_T == 4
+#define NUMA_QUERY_CHUNK_SIZE 16
+#else
+#define NUMA_QUERY_CHUNK_SIZE 1024
+#endif
+
 /* libnuma requires initialization as per numa(3) on Linux */
 int
 pg_numa_init(void)
@@ -42,11 +56,48 @@ pg_numa_init(void)
  * We use move_pages(2) syscall here - instead of get_mempolicy(2) - as the
  * first one allows us to batch and query about many memory pages in one single
  * giant system call that is way faster.
+ *
+ * We call numa_move_pages() for smaller chunks of the whole array. The first
+ * reason is to work around a kernel bug, but also to allow interrupting the
+ * query between the calls (for many pointers processing the whole array can
+ * take a lot of time).
  */
 int
 pg_numa_query_pages(int pid, unsigned long count, void **pages, int *status)
 {
-	return numa_move_pages(pid, count, pages, NULL, status, 0);
+	unsigned long next = 0;
+	int			ret = 0;
+
+	/*
+	 * Chunk pointers passed to numa_move_pages to NUMA_QUERY_CHUNK_SIZE
+	 * items, to work around a kernel bug in do_pages_stat().
+	 */
+	while (next < count)
+	{
+		unsigned long count_chunk = Min(count - next,
+										NUMA_QUERY_CHUNK_SIZE);
+
+		CHECK_FOR_INTERRUPTS();
+
+		/*
+		 * Bail out if any of the chunks errors out (ret<0). We ignore (ret>0)
+		 * which is used to return number of nonmigrated pages, but we're not
+		 * migrating any pages here.
+		 */
+		ret = numa_move_pages(pid, count_chunk, &pages[next], NULL, &status[next], 0);
+		if (ret < 0)
+		{
+			/* plain error, return as is */
+			return ret;
+		}
+
+		next += count_chunk;
+	}
+
+	/* should have consumed the input array exactly */
+	Assert(next == count);
+
+	return 0;
 }
 
 int
diff --git a/src/port/pgmkdirp.c b/src/port/pgmkdirp.c
index d943559760d89..7d7cea4dd0ea1 100644
--- a/src/port/pgmkdirp.c
+++ b/src/port/pgmkdirp.c
@@ -73,7 +73,7 @@ pg_mkdir_p(char *path, int omode)
 		if (p[0] == '/' && p[1] == '/')
 		{
 			/* network drive */
-			p = strstr(p + 2, "/");
+			p = strchr(p + 2, '/');
 			if (p == NULL)
 			{
 				errno = EINVAL;
diff --git a/src/test/authentication/t/003_peer.pl b/src/test/authentication/t/003_peer.pl
index f2320b62c8721..c751fbdbaa5ec 100644
--- a/src/test/authentication/t/003_peer.pl
+++ b/src/test/authentication/t/003_peer.pl
@@ -171,7 +171,8 @@ sub test_role
 
 # Test with regular expression in user name map.
 # Extract the last 3 characters from the system_user
-# or the entire system_user (if its length is <= -3).
+# or the entire system_user name (if its length is <= 3).
+# We trust this will not include any regex metacharacters.
 my $regex_test_string = substr($system_user, -3);
 
 # Success as the system user regular expression matches.
@@ -210,12 +211,17 @@ sub test_role
 	log_like =>
 	  [qr/connection authenticated: identity="$system_user" method=peer/]);
 
+# Create target role for \1 tests.
+my $mapped_name = "test${regex_test_string}map${regex_test_string}user";
+$node->safe_psql('postgres', "CREATE ROLE $mapped_name LOGIN");
+
 # Success as the regular expression matches and \1 is replaced in the given
 # subexpression.
-reset_pg_ident($node, 'mypeermap', qq{/^$system_user(.*)\$}, 'test\1mapuser');
+reset_pg_ident($node, 'mypeermap', qq{/^.*($regex_test_string)\$},
+	'test\1map\1user');
 test_role(
 	$node,
-	qq{testmapuser},
+	$mapped_name,
 	'peer',
 	0,
 	'with regular expression in user name map with \1 replaced',
@@ -224,11 +230,11 @@ sub test_role
 
 # Success as the regular expression matches and \1 is replaced in the given
 # subexpression, even if quoted.
-reset_pg_ident($node, 'mypeermap', qq{/^$system_user(.*)\$},
-	'"test\1mapuser"');
+reset_pg_ident($node, 'mypeermap', qq{/^.*($regex_test_string)\$},
+	'"test\1map\1user"');
 test_role(
 	$node,
-	qq{testmapuser},
+	$mapped_name,
 	'peer',
 	0,
 	'with regular expression in user name map with quoted \1 replaced',
diff --git a/src/test/isolation/expected/merge-match-recheck.out b/src/test/isolation/expected/merge-match-recheck.out
index 9a44a5959270b..90300f1db5ab3 100644
--- a/src/test/isolation/expected/merge-match-recheck.out
+++ b/src/test/isolation/expected/merge-match-recheck.out
@@ -241,19 +241,28 @@ starting permutation: update_bal1_tg merge_bal_tg c2 select1_tg c1
 s2: NOTICE:  Update: (1,160,s1,setup) -> (1,50,s1,"setup updated by update_bal1_tg")
 step update_bal1_tg: UPDATE target_tg t SET balance = 50, val = t.val || ' updated by update_bal1_tg' WHERE t.key = 1;
 step merge_bal_tg: 
-  MERGE INTO target_tg t
-  USING (SELECT 1 as key) s
-  ON s.key = t.key
-  WHEN MATCHED AND balance < 100 THEN
-	UPDATE SET balance = balance * 2, val = t.val || ' when1'
-  WHEN MATCHED AND balance < 200 THEN
-	UPDATE SET balance = balance * 4, val = t.val || ' when2'
-  WHEN MATCHED AND balance < 300 THEN
-	UPDATE SET balance = balance * 8, val = t.val || ' when3';
+  WITH t AS (
+    MERGE INTO target_tg t
+    USING (SELECT 1 as key) s
+    ON s.key = t.key
+    WHEN MATCHED AND balance < 100 THEN
+      UPDATE SET balance = balance * 2, val = t.val || ' when1'
+    WHEN MATCHED AND balance < 200 THEN
+      UPDATE SET balance = balance * 4, val = t.val || ' when2'
+    WHEN MATCHED AND balance < 300 THEN
+      UPDATE SET balance = balance * 8, val = t.val || ' when3'
+    RETURNING t.*
+  )
+  SELECT * FROM t;
  <waiting ...>
 step c2: COMMIT;
 s1: NOTICE:  Update: (1,50,s1,"setup updated by update_bal1_tg") -> (1,100,s1,"setup updated by update_bal1_tg when1")
 step merge_bal_tg: <... completed>
+key|balance|status|val                                  
+---+-------+------+-------------------------------------
+  1|    100|s1    |setup updated by update_bal1_tg when1
+(1 row)
+
 step select1_tg: SELECT * FROM target_tg;
 key|balance|status|val                                  
 ---+-------+------+-------------------------------------
diff --git a/src/test/isolation/specs/merge-match-recheck.spec b/src/test/isolation/specs/merge-match-recheck.spec
index 26266b8c2978e..15226e40c9efc 100644
--- a/src/test/isolation/specs/merge-match-recheck.spec
+++ b/src/test/isolation/specs/merge-match-recheck.spec
@@ -99,15 +99,19 @@ step "merge_bal_pa"
 }
 step "merge_bal_tg"
 {
-  MERGE INTO target_tg t
-  USING (SELECT 1 as key) s
-  ON s.key = t.key
-  WHEN MATCHED AND balance < 100 THEN
-	UPDATE SET balance = balance * 2, val = t.val || ' when1'
-  WHEN MATCHED AND balance < 200 THEN
-	UPDATE SET balance = balance * 4, val = t.val || ' when2'
-  WHEN MATCHED AND balance < 300 THEN
-	UPDATE SET balance = balance * 8, val = t.val || ' when3';
+  WITH t AS (
+    MERGE INTO target_tg t
+    USING (SELECT 1 as key) s
+    ON s.key = t.key
+    WHEN MATCHED AND balance < 100 THEN
+      UPDATE SET balance = balance * 2, val = t.val || ' when1'
+    WHEN MATCHED AND balance < 200 THEN
+      UPDATE SET balance = balance * 4, val = t.val || ' when2'
+    WHEN MATCHED AND balance < 300 THEN
+      UPDATE SET balance = balance * 8, val = t.val || ' when3'
+    RETURNING t.*
+  )
+  SELECT * FROM t;
 }
 
 step "merge_delete"
diff --git a/src/test/modules/Makefile b/src/test/modules/Makefile
index aa1d27bbed310..7d3d3d52b45e9 100644
--- a/src/test/modules/Makefile
+++ b/src/test/modules/Makefile
@@ -15,6 +15,7 @@ SUBDIRS = \
 		  plsample \
 		  spgist_name_ops \
 		  test_aio \
+		  test_binaryheap \
 		  test_bloomfilter \
 		  test_copy_callbacks \
 		  test_custom_rmgrs \
diff --git a/src/test/modules/commit_ts/t/001_base.pl b/src/test/modules/commit_ts/t/001_base.pl
index 1953b18f6b3c3..50e79ce640937 100644
--- a/src/test/modules/commit_ts/t/001_base.pl
+++ b/src/test/modules/commit_ts/t/001_base.pl
@@ -11,8 +11,7 @@
 use PostgreSQL::Test::Cluster;
 
 my $node = PostgreSQL::Test::Cluster->new('foxtrot');
-$node->init;
-$node->append_conf('postgresql.conf', 'track_commit_timestamp = on');
+$node->init(extra => [ '-c', "track_commit_timestamp=on" ]);
 $node->start;
 
 # Create a table, compare "now()" to the commit TS of its xmin
diff --git a/src/test/modules/injection_points/expected/injection_points.out b/src/test/modules/injection_points/expected/injection_points.out
index 43bcdd01582f7..382f3b0bf8848 100644
--- a/src/test/modules/injection_points/expected/injection_points.out
+++ b/src/test/modules/injection_points/expected/injection_points.out
@@ -39,6 +39,15 @@ SELECT injection_points_attach('TestInjectionLog2', 'notice');
  
 (1 row)
 
+SELECT point_name, library, function FROM injection_points_list()
+  ORDER BY point_name COLLATE "C";
+     point_name     |     library      |     function     
+--------------------+------------------+------------------
+ TestInjectionError | injection_points | injection_error
+ TestInjectionLog   | injection_points | injection_notice
+ TestInjectionLog2  | injection_points | injection_notice
+(3 rows)
+
 SELECT injection_points_run('TestInjectionBooh'); -- nothing
  injection_points_run 
 ----------------------
@@ -298,5 +307,12 @@ SELECT injection_points_detach('TestConditionLocal1');
  
 (1 row)
 
+-- No points should be left around.
+SELECT point_name, library, function FROM injection_points_list()
+  ORDER BY point_name COLLATE "C";
+ point_name | library | function 
+------------+---------+----------
+(0 rows)
+
 DROP EXTENSION injection_points;
 DROP FUNCTION wait_pid;
diff --git a/src/test/modules/injection_points/injection_points--1.0.sql b/src/test/modules/injection_points/injection_points--1.0.sql
index cc76b1bf99ae6..5f5657b2043ca 100644
--- a/src/test/modules/injection_points/injection_points--1.0.sql
+++ b/src/test/modules/injection_points/injection_points--1.0.sql
@@ -77,6 +77,18 @@ RETURNS void
 AS 'MODULE_PATHNAME', 'injection_points_detach'
 LANGUAGE C STRICT PARALLEL UNSAFE;
 
+--
+-- injection_points_list()
+--
+-- List of all the injection points currently attached.
+--
+CREATE FUNCTION injection_points_list(OUT point_name text,
+   OUT library text,
+   OUT function text)
+RETURNS SETOF record
+AS 'MODULE_PATHNAME', 'injection_points_list'
+LANGUAGE C STRICT VOLATILE PARALLEL RESTRICTED;
+
 --
 -- injection_points_stats_numcalls()
 --
diff --git a/src/test/modules/injection_points/injection_points.c b/src/test/modules/injection_points/injection_points.c
index 3da0cbc10e08f..3113830111700 100644
--- a/src/test/modules/injection_points/injection_points.c
+++ b/src/test/modules/injection_points/injection_points.c
@@ -18,6 +18,7 @@
 #include "postgres.h"
 
 #include "fmgr.h"
+#include "funcapi.h"
 #include "injection_stats.h"
 #include "miscadmin.h"
 #include "nodes/pg_list.h"
@@ -545,6 +546,44 @@ injection_points_detach(PG_FUNCTION_ARGS)
 	PG_RETURN_VOID();
 }
 
+/*
+ * SQL function for listing all the injection points attached.
+ */
+PG_FUNCTION_INFO_V1(injection_points_list);
+Datum
+injection_points_list(PG_FUNCTION_ARGS)
+{
+#define NUM_INJECTION_POINTS_LIST 3
+	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
+	List	   *inj_points;
+	ListCell   *lc;
+
+	/* Build a tuplestore to return our results in */
+	InitMaterializedSRF(fcinfo, 0);
+
+	inj_points = InjectionPointList();
+
+	foreach(lc, inj_points)
+	{
+		Datum		values[NUM_INJECTION_POINTS_LIST];
+		bool		nulls[NUM_INJECTION_POINTS_LIST];
+		InjectionPointData *inj_point = lfirst(lc);
+
+		memset(values, 0, sizeof(values));
+		memset(nulls, 0, sizeof(nulls));
+
+		values[0] = PointerGetDatum(cstring_to_text(inj_point->name));
+		values[1] = PointerGetDatum(cstring_to_text(inj_point->library));
+		values[2] = PointerGetDatum(cstring_to_text(inj_point->function));
+
+		/* shove row into tuplestore */
+		tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
+	}
+
+	return (Datum) 0;
+#undef NUM_INJECTION_POINTS_LIST
+}
+
 
 void
 _PG_init(void)
diff --git a/src/test/modules/injection_points/injection_stats.c b/src/test/modules/injection_points/injection_stats.c
index 14903c629e0d1..e3947b23ba573 100644
--- a/src/test/modules/injection_points/injection_stats.c
+++ b/src/test/modules/injection_points/injection_stats.c
@@ -59,7 +59,7 @@ static const PgStat_KindInfo injection_stats = {
 /*
  * Kind ID reserved for statistics of injection points.
  */
-#define PGSTAT_KIND_INJECTION	129
+#define PGSTAT_KIND_INJECTION	25
 
 /* Track if stats are loaded */
 static bool inj_stats_loaded = false;
diff --git a/src/test/modules/injection_points/injection_stats_fixed.c b/src/test/modules/injection_points/injection_stats_fixed.c
index 3d0c01bdd05ab..bc54c79d190b9 100644
--- a/src/test/modules/injection_points/injection_stats_fixed.c
+++ b/src/test/modules/injection_points/injection_stats_fixed.c
@@ -64,7 +64,7 @@ static const PgStat_KindInfo injection_stats_fixed = {
 /*
  * Kind ID reserved for statistics of injection points.
  */
-#define PGSTAT_KIND_INJECTION_FIXED	130
+#define PGSTAT_KIND_INJECTION_FIXED	26
 
 /* Track if fixed-numbered stats are loaded */
 static bool inj_fixed_loaded = false;
diff --git a/src/test/modules/injection_points/meson.build b/src/test/modules/injection_points/meson.build
index ce778ccf9ac45..20390d6b4bf2f 100644
--- a/src/test/modules/injection_points/meson.build
+++ b/src/test/modules/injection_points/meson.build
@@ -39,7 +39,7 @@ tests += {
       'reindex_conc',
       'vacuum',
     ],
-    'regress_args': ['--dlpath', meson.build_root() / 'src/test/regress'],
+    'regress_args': ['--dlpath', meson.project_build_root() / 'src/test/regress'],
     # The injection points are cluster-wide, so disable installcheck
     'runningcheck': false,
   },
diff --git a/src/test/modules/injection_points/sql/injection_points.sql b/src/test/modules/injection_points/sql/injection_points.sql
index d9748331c7715..874421e9c1187 100644
--- a/src/test/modules/injection_points/sql/injection_points.sql
+++ b/src/test/modules/injection_points/sql/injection_points.sql
@@ -18,6 +18,9 @@ SELECT injection_points_attach('TestInjectionError', 'error');
 SELECT injection_points_attach('TestInjectionLog', 'notice');
 SELECT injection_points_attach('TestInjectionLog2', 'notice');
 
+SELECT point_name, library, function FROM injection_points_list()
+  ORDER BY point_name COLLATE "C";
+
 SELECT injection_points_run('TestInjectionBooh'); -- nothing
 SELECT injection_points_run('TestInjectionLog2'); -- notice
 SELECT injection_points_run('TestInjectionLog2', NULL); -- notice
@@ -85,5 +88,9 @@ SELECT injection_points_detach('TestConditionError');
 SELECT injection_points_attach('TestConditionLocal1', 'error');
 SELECT injection_points_detach('TestConditionLocal1');
 
+-- No points should be left around.
+SELECT point_name, library, function FROM injection_points_list()
+  ORDER BY point_name COLLATE "C";
+
 DROP EXTENSION injection_points;
 DROP FUNCTION wait_pid;
diff --git a/src/test/modules/meson.build b/src/test/modules/meson.build
index 9de0057bd1d43..dd5cd065ba10c 100644
--- a/src/test/modules/meson.build
+++ b/src/test/modules/meson.build
@@ -14,6 +14,7 @@ subdir('plsample')
 subdir('spgist_name_ops')
 subdir('ssl_passphrase_callback')
 subdir('test_aio')
+subdir('test_binaryheap')
 subdir('test_bloomfilter')
 subdir('test_copy_callbacks')
 subdir('test_custom_rmgrs')
diff --git a/src/test/modules/oauth_validator/meson.build b/src/test/modules/oauth_validator/meson.build
index e190f9cf15a4a..a6f937fd7d734 100644
--- a/src/test/modules/oauth_validator/meson.build
+++ b/src/test/modules/oauth_validator/meson.build
@@ -77,7 +77,7 @@ tests += {
       't/002_client.pl',
     ],
     'env': {
-      'PYTHON': python.path(),
+      'PYTHON': python.full_path(),
       'with_libcurl': oauth_flow_supported ? 'yes' : 'no',
       'with_python': 'yes',
     },
diff --git a/src/test/modules/test_binaryheap/.gitignore b/src/test/modules/test_binaryheap/.gitignore
new file mode 100644
index 0000000000000..5dcb3ff972350
--- /dev/null
+++ b/src/test/modules/test_binaryheap/.gitignore
@@ -0,0 +1,4 @@
+# Generated subdirectories
+/log/
+/results/
+/tmp_check/
diff --git a/src/test/modules/test_binaryheap/Makefile b/src/test/modules/test_binaryheap/Makefile
new file mode 100644
index 0000000000000..d310fbc9e88fb
--- /dev/null
+++ b/src/test/modules/test_binaryheap/Makefile
@@ -0,0 +1,24 @@
+# src/test/modules/test_binaryheap/Makefile
+
+MODULE_big = test_binaryheap
+OBJS = \
+	$(WIN32RES) \
+	test_binaryheap.o
+
+PGFILEDESC = "test_binaryheap - test code for binaryheap"
+
+EXTENSION = test_binaryheap
+DATA = test_binaryheap--1.0.sql
+
+REGRESS = test_binaryheap
+
+ifdef USE_PGXS
+PG_CONFIG = pg_config
+PGXS := $(shell $(PG_CONFIG) --pgxs)
+include $(PGXS)
+else
+subdir = src/test/modules/test_binaryheap
+top_builddir = ../../../..
+include $(top_builddir)/src/Makefile.global
+include $(top_srcdir)/contrib/contrib-global.mk
+endif
diff --git a/src/test/modules/test_binaryheap/expected/test_binaryheap.out b/src/test/modules/test_binaryheap/expected/test_binaryheap.out
new file mode 100644
index 0000000000000..16ce07875e3f7
--- /dev/null
+++ b/src/test/modules/test_binaryheap/expected/test_binaryheap.out
@@ -0,0 +1,12 @@
+CREATE EXTENSION test_binaryheap;
+--
+-- These tests don't produce any interesting output.  We're checking that
+-- the operations complete without crashing or hanging and that none of their
+-- internal sanity tests fail.
+--
+SELECT test_binaryheap();
+ test_binaryheap 
+-----------------
+ 
+(1 row)
+
diff --git a/src/test/modules/test_binaryheap/meson.build b/src/test/modules/test_binaryheap/meson.build
new file mode 100644
index 0000000000000..816a43c93e945
--- /dev/null
+++ b/src/test/modules/test_binaryheap/meson.build
@@ -0,0 +1,33 @@
+# Copyright (c) 2025, PostgreSQL Global Development Group
+
+test_binaryheap_sources = files(
+  'test_binaryheap.c',
+)
+
+if host_system == 'windows'
+  test_binaryheap_sources += rc_lib_gen.process(win32ver_rc, extra_args: [
+    '--NAME', 'test_binaryheap',
+    '--FILEDESC', 'test_binaryheap - test code for binaryheap',])
+endif
+
+test_binaryheap = shared_module('test_binaryheap',
+  test_binaryheap_sources,
+  kwargs: pg_test_mod_args,
+)
+test_install_libs += test_binaryheap
+
+test_install_data += files(
+  'test_binaryheap.control',
+  'test_binaryheap--1.0.sql',
+)
+
+tests += {
+  'name': 'test_binaryheap',
+  'sd': meson.current_source_dir(),
+  'bd': meson.current_build_dir(),
+  'regress': {
+    'sql': [
+      'test_binaryheap',
+    ],
+  },
+}
diff --git a/src/test/modules/test_binaryheap/sql/test_binaryheap.sql b/src/test/modules/test_binaryheap/sql/test_binaryheap.sql
new file mode 100644
index 0000000000000..8439545815b37
--- /dev/null
+++ b/src/test/modules/test_binaryheap/sql/test_binaryheap.sql
@@ -0,0 +1,8 @@
+CREATE EXTENSION test_binaryheap;
+
+--
+-- These tests don't produce any interesting output.  We're checking that
+-- the operations complete without crashing or hanging and that none of their
+-- internal sanity tests fail.
+--
+SELECT test_binaryheap();
diff --git a/src/test/modules/test_binaryheap/test_binaryheap--1.0.sql b/src/test/modules/test_binaryheap/test_binaryheap--1.0.sql
new file mode 100644
index 0000000000000..cddceeee60337
--- /dev/null
+++ b/src/test/modules/test_binaryheap/test_binaryheap--1.0.sql
@@ -0,0 +1,7 @@
+/* src/test/modules/test_binaryheap/test_binaryheap--1.0.sql */
+
+-- complain if script is sourced in psql, rather than via CREATE EXTENSION
+\echo Use "CREATE EXTENSION test_binaryheap" to load this file. \quit
+
+CREATE FUNCTION test_binaryheap() RETURNS VOID
+	AS 'MODULE_PATHNAME' LANGUAGE C;
diff --git a/src/test/modules/test_binaryheap/test_binaryheap.c b/src/test/modules/test_binaryheap/test_binaryheap.c
new file mode 100644
index 0000000000000..583dae1da30d5
--- /dev/null
+++ b/src/test/modules/test_binaryheap/test_binaryheap.c
@@ -0,0 +1,275 @@
+/*--------------------------------------------------------------------------
+ *
+ * test_binaryheap.c
+ *		Test correctness of binary heap implementation.
+ *
+ * Copyright (c) 2025, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ *		src/test/modules/test_binaryheap/test_binaryheap.c
+ *
+ * -------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#include "common/int.h"
+#include "common/pg_prng.h"
+#include "fmgr.h"
+#include "lib/binaryheap.h"
+
+PG_MODULE_MAGIC;
+
+/*
+ * Test binaryheap_comparator for max-heap of integers.
+ */
+static int
+int_cmp(Datum a, Datum b, void *arg)
+{
+	return pg_cmp_s32(DatumGetInt32(a), DatumGetInt32(b));
+}
+
+/*
+ * Loops through all nodes and returns the maximum value.
+ */
+static int
+get_max_from_heap(binaryheap *heap)
+{
+	int			max = -1;
+
+	for (int i = 0; i < binaryheap_size(heap); i++)
+		max = Max(max, DatumGetInt32(binaryheap_get_node(heap, i)));
+
+	return max;
+}
+
+/*
+ * Generate a random permutation of the integers 0..size-1.
+ */
+static int *
+get_permutation(int size)
+{
+	int		   *permutation = (int *) palloc(size * sizeof(int));
+
+	permutation[0] = 0;
+
+	/*
+	 * This is the "inside-out" variant of the Fisher-Yates shuffle algorithm.
+	 * Notionally, we append each new value to the array and then swap it with
+	 * a randomly-chosen array element (possibly including itself, else we
+	 * fail to generate permutations with the last integer last).  The swap
+	 * step can be optimized by combining it with the insertion.
+	 */
+	for (int i = 1; i < size; i++)
+	{
+		int			j = pg_prng_uint64_range(&pg_global_prng_state, 0, i);
+
+		if (j < i)				/* avoid fetching undefined data if j=i */
+			permutation[i] = permutation[j];
+		permutation[j] = i;
+	}
+
+	return permutation;
+}
+
+/*
+ * Ensure that the heap property holds for the given heap, i.e., each parent is
+ * greater than or equal to its children.
+ */
+static void
+verify_heap_property(binaryheap *heap)
+{
+	for (int i = 0; i < binaryheap_size(heap); i++)
+	{
+		int			left = 2 * i + 1;
+		int			right = 2 * i + 2;
+		int			parent_val = DatumGetInt32(binaryheap_get_node(heap, i));
+
+		if (left < binaryheap_size(heap) &&
+			parent_val < DatumGetInt32(binaryheap_get_node(heap, left)))
+			elog(ERROR, "parent node less than left child");
+
+		if (right < binaryheap_size(heap) &&
+			parent_val < DatumGetInt32(binaryheap_get_node(heap, right)))
+			elog(ERROR, "parent node less than right child");
+	}
+}
+
+/*
+ * Check correctness of basic operations.
+ */
+static void
+test_basic(int size)
+{
+	binaryheap *heap = binaryheap_allocate(size, int_cmp, NULL);
+	int		   *permutation = get_permutation(size);
+
+	if (!binaryheap_empty(heap))
+		elog(ERROR, "new heap not empty");
+	if (binaryheap_size(heap) != 0)
+		elog(ERROR, "wrong size for new heap");
+
+	for (int i = 0; i < size; i++)
+	{
+		binaryheap_add(heap, Int32GetDatum(permutation[i]));
+		verify_heap_property(heap);
+	}
+
+	if (binaryheap_empty(heap))
+		elog(ERROR, "heap empty after adding values");
+	if (binaryheap_size(heap) != size)
+		elog(ERROR, "wrong size for heap after adding values");
+
+	if (DatumGetInt32(binaryheap_first(heap)) != get_max_from_heap(heap))
+		elog(ERROR, "incorrect root node after adding values");
+
+	for (int i = 0; i < size; i++)
+	{
+		int			expected = get_max_from_heap(heap);
+		int			actual = DatumGetInt32(binaryheap_remove_first(heap));
+
+		if (actual != expected)
+			elog(ERROR, "incorrect root node after removing root");
+		verify_heap_property(heap);
+	}
+
+	if (!binaryheap_empty(heap))
+		elog(ERROR, "heap not empty after removing all nodes");
+}
+
+/*
+ * Test building heap after unordered additions.
+ */
+static void
+test_build(int size)
+{
+	binaryheap *heap = binaryheap_allocate(size, int_cmp, NULL);
+	int		   *permutation = get_permutation(size);
+
+	for (int i = 0; i < size; i++)
+		binaryheap_add_unordered(heap, Int32GetDatum(permutation[i]));
+
+	if (binaryheap_size(heap) != size)
+		elog(ERROR, "wrong size for heap after unordered additions");
+
+	binaryheap_build(heap);
+	verify_heap_property(heap);
+}
+
+/*
+ * Test removing nodes.
+ */
+static void
+test_remove_node(int size)
+{
+	binaryheap *heap = binaryheap_allocate(size, int_cmp, NULL);
+	int		   *permutation = get_permutation(size);
+	int			remove_count = pg_prng_uint64_range(&pg_global_prng_state,
+													0, size - 1);
+
+	for (int i = 0; i < size; i++)
+		binaryheap_add(heap, Int32GetDatum(permutation[i]));
+
+	for (int i = 0; i < remove_count; i++)
+	{
+		int			idx = pg_prng_uint64_range(&pg_global_prng_state,
+											   0, binaryheap_size(heap) - 1);
+
+		binaryheap_remove_node(heap, idx);
+		verify_heap_property(heap);
+	}
+
+	if (binaryheap_size(heap) != size - remove_count)
+		elog(ERROR, "wrong size after removing nodes");
+}
+
+/*
+ * Test replacing the root node.
+ */
+static void
+test_replace_first(int size)
+{
+	binaryheap *heap = binaryheap_allocate(size, int_cmp, NULL);
+
+	for (int i = 0; i < size; i++)
+		binaryheap_add(heap, Int32GetDatum(i));
+
+	/*
+	 * Replace root with a value smaller than everything in the heap.
+	 */
+	binaryheap_replace_first(heap, Int32GetDatum(-1));
+	verify_heap_property(heap);
+
+	/*
+	 * Replace root with a value in the middle of the heap.
+	 */
+	binaryheap_replace_first(heap, Int32GetDatum(size / 2));
+	verify_heap_property(heap);
+
+	/*
+	 * Replace root with a larger value than everything in the heap.
+	 */
+	binaryheap_replace_first(heap, Int32GetDatum(size + 1));
+	verify_heap_property(heap);
+}
+
+/*
+ * Test duplicate values.
+ */
+static void
+test_duplicates(int size)
+{
+	binaryheap *heap = binaryheap_allocate(size, int_cmp, NULL);
+	int			dup = pg_prng_uint64_range(&pg_global_prng_state, 0, size - 1);
+
+	for (int i = 0; i < size; i++)
+		binaryheap_add(heap, Int32GetDatum(dup));
+
+	for (int i = 0; i < size; i++)
+	{
+		if (DatumGetInt32(binaryheap_remove_first(heap)) != dup)
+			elog(ERROR, "unexpected value in heap with duplicates");
+	}
+}
+
+/*
+ * Test resetting.
+ */
+static void
+test_reset(int size)
+{
+	binaryheap *heap = binaryheap_allocate(size, int_cmp, NULL);
+
+	for (int i = 0; i < size; i++)
+		binaryheap_add(heap, Int32GetDatum(i));
+
+	binaryheap_reset(heap);
+
+	if (!binaryheap_empty(heap))
+		elog(ERROR, "heap not empty after resetting");
+}
+
+/*
+ * SQL-callable entry point to perform all tests.
+ */
+PG_FUNCTION_INFO_V1(test_binaryheap);
+
+Datum
+test_binaryheap(PG_FUNCTION_ARGS)
+{
+	static const int test_sizes[] = {1, 2, 3, 10, 100, 1000};
+
+	for (int i = 0; i < sizeof(test_sizes) / sizeof(int); i++)
+	{
+		int			size = test_sizes[i];
+
+		test_basic(size);
+		test_build(size);
+		test_remove_node(size);
+		test_replace_first(size);
+		test_duplicates(size);
+		test_reset(size);
+	}
+
+	PG_RETURN_VOID();
+}
diff --git a/src/test/modules/test_binaryheap/test_binaryheap.control b/src/test/modules/test_binaryheap/test_binaryheap.control
new file mode 100644
index 0000000000000..dd0785e05bdaf
--- /dev/null
+++ b/src/test/modules/test_binaryheap/test_binaryheap.control
@@ -0,0 +1,5 @@
+# test_binaryheap extension
+comment = 'Test code for binaryheap'
+default_version = '1.0'
+module_pathname = '$libdir/test_binaryheap'
+relocatable = true
diff --git a/src/test/modules/test_dsm_registry/expected/test_dsm_registry.out b/src/test/modules/test_dsm_registry/expected/test_dsm_registry.out
index 8ffbd343a05af..ca8abbb377e6b 100644
--- a/src/test/modules/test_dsm_registry/expected/test_dsm_registry.out
+++ b/src/test/modules/test_dsm_registry/expected/test_dsm_registry.out
@@ -1,3 +1,10 @@
+SELECT name, type, size IS DISTINCT FROM 0 AS size
+FROM pg_dsm_registry_allocations
+WHERE name like 'test_dsm_registry%' ORDER BY name;
+ name | type | size 
+------+------+------
+(0 rows)
+
 CREATE EXTENSION test_dsm_registry;
 SELECT set_val_in_shmem(1236);
  set_val_in_shmem 
@@ -5,6 +12,12 @@ SELECT set_val_in_shmem(1236);
  
 (1 row)
 
+SELECT set_val_in_hash('test', '1414');
+ set_val_in_hash 
+-----------------
+ 
+(1 row)
+
 \c
 SELECT get_val_in_shmem();
  get_val_in_shmem 
@@ -12,3 +25,20 @@ SELECT get_val_in_shmem();
              1236
 (1 row)
 
+SELECT get_val_in_hash('test');
+ get_val_in_hash 
+-----------------
+ 1414
+(1 row)
+
+\c
+SELECT name, type, size IS DISTINCT FROM 0 AS size
+FROM pg_dsm_registry_allocations
+WHERE name like 'test_dsm_registry%' ORDER BY name;
+          name          |  type   | size 
+------------------------+---------+------
+ test_dsm_registry_dsa  | area    | t
+ test_dsm_registry_dsm  | segment | t
+ test_dsm_registry_hash | hash    | t
+(3 rows)
+
diff --git a/src/test/modules/test_dsm_registry/sql/test_dsm_registry.sql b/src/test/modules/test_dsm_registry/sql/test_dsm_registry.sql
index b3351be0a16bc..965a3f1ebb63a 100644
--- a/src/test/modules/test_dsm_registry/sql/test_dsm_registry.sql
+++ b/src/test/modules/test_dsm_registry/sql/test_dsm_registry.sql
@@ -1,4 +1,13 @@
+SELECT name, type, size IS DISTINCT FROM 0 AS size
+FROM pg_dsm_registry_allocations
+WHERE name like 'test_dsm_registry%' ORDER BY name;
 CREATE EXTENSION test_dsm_registry;
 SELECT set_val_in_shmem(1236);
+SELECT set_val_in_hash('test', '1414');
 \c
 SELECT get_val_in_shmem();
+SELECT get_val_in_hash('test');
+\c
+SELECT name, type, size IS DISTINCT FROM 0 AS size
+FROM pg_dsm_registry_allocations
+WHERE name like 'test_dsm_registry%' ORDER BY name;
diff --git a/src/test/modules/test_dsm_registry/test_dsm_registry--1.0.sql b/src/test/modules/test_dsm_registry/test_dsm_registry--1.0.sql
index 8c55b0919b11f..5da45155be9f5 100644
--- a/src/test/modules/test_dsm_registry/test_dsm_registry--1.0.sql
+++ b/src/test/modules/test_dsm_registry/test_dsm_registry--1.0.sql
@@ -8,3 +8,9 @@ CREATE FUNCTION set_val_in_shmem(val INT) RETURNS VOID
 
 CREATE FUNCTION get_val_in_shmem() RETURNS INT
 	AS 'MODULE_PATHNAME' LANGUAGE C;
+
+CREATE FUNCTION set_val_in_hash(key TEXT, val TEXT) RETURNS VOID
+	AS 'MODULE_PATHNAME' LANGUAGE C;
+
+CREATE FUNCTION get_val_in_hash(key TEXT) RETURNS TEXT
+	AS 'MODULE_PATHNAME' LANGUAGE C;
diff --git a/src/test/modules/test_dsm_registry/test_dsm_registry.c b/src/test/modules/test_dsm_registry/test_dsm_registry.c
index 96a890be22826..141c8ed1b34e3 100644
--- a/src/test/modules/test_dsm_registry/test_dsm_registry.c
+++ b/src/test/modules/test_dsm_registry/test_dsm_registry.c
@@ -15,6 +15,7 @@
 #include "fmgr.h"
 #include "storage/dsm_registry.h"
 #include "storage/lwlock.h"
+#include "utils/builtins.h"
 
 PG_MODULE_MAGIC;
 
@@ -24,15 +25,31 @@ typedef struct TestDSMRegistryStruct
 	LWLock		lck;
 } TestDSMRegistryStruct;
 
-static TestDSMRegistryStruct *tdr_state;
+typedef struct TestDSMRegistryHashEntry
+{
+	char		key[64];
+	dsa_pointer val;
+} TestDSMRegistryHashEntry;
+
+static TestDSMRegistryStruct *tdr_dsm;
+static dsa_area *tdr_dsa;
+static dshash_table *tdr_hash;
+
+static const dshash_parameters dsh_params = {
+	offsetof(TestDSMRegistryHashEntry, val),
+	sizeof(TestDSMRegistryHashEntry),
+	dshash_strcmp,
+	dshash_strhash,
+	dshash_strcpy
+};
 
 static void
-tdr_init_shmem(void *ptr)
+init_tdr_dsm(void *ptr)
 {
-	TestDSMRegistryStruct *state = (TestDSMRegistryStruct *) ptr;
+	TestDSMRegistryStruct *dsm = (TestDSMRegistryStruct *) ptr;
 
-	LWLockInitialize(&state->lck, LWLockNewTrancheId());
-	state->val = 0;
+	LWLockInitialize(&dsm->lck, LWLockNewTrancheId());
+	dsm->val = 0;
 }
 
 static void
@@ -40,11 +57,17 @@ tdr_attach_shmem(void)
 {
 	bool		found;
 
-	tdr_state = GetNamedDSMSegment("test_dsm_registry",
-								   sizeof(TestDSMRegistryStruct),
-								   tdr_init_shmem,
-								   &found);
-	LWLockRegisterTranche(tdr_state->lck.tranche, "test_dsm_registry");
+	tdr_dsm = GetNamedDSMSegment("test_dsm_registry_dsm",
+								 sizeof(TestDSMRegistryStruct),
+								 init_tdr_dsm,
+								 &found);
+	LWLockRegisterTranche(tdr_dsm->lck.tranche, "test_dsm_registry");
+
+	if (tdr_dsa == NULL)
+		tdr_dsa = GetNamedDSA("test_dsm_registry_dsa", &found);
+
+	if (tdr_hash == NULL)
+		tdr_hash = GetNamedDSHash("test_dsm_registry_hash", &dsh_params, &found);
 }
 
 PG_FUNCTION_INFO_V1(set_val_in_shmem);
@@ -53,9 +76,9 @@ set_val_in_shmem(PG_FUNCTION_ARGS)
 {
 	tdr_attach_shmem();
 
-	LWLockAcquire(&tdr_state->lck, LW_EXCLUSIVE);
-	tdr_state->val = PG_GETARG_INT32(0);
-	LWLockRelease(&tdr_state->lck);
+	LWLockAcquire(&tdr_dsm->lck, LW_EXCLUSIVE);
+	tdr_dsm->val = PG_GETARG_INT32(0);
+	LWLockRelease(&tdr_dsm->lck);
 
 	PG_RETURN_VOID();
 }
@@ -68,9 +91,57 @@ get_val_in_shmem(PG_FUNCTION_ARGS)
 
 	tdr_attach_shmem();
 
-	LWLockAcquire(&tdr_state->lck, LW_SHARED);
-	ret = tdr_state->val;
-	LWLockRelease(&tdr_state->lck);
+	LWLockAcquire(&tdr_dsm->lck, LW_SHARED);
+	ret = tdr_dsm->val;
+	LWLockRelease(&tdr_dsm->lck);
 
 	PG_RETURN_INT32(ret);
 }
+
+PG_FUNCTION_INFO_V1(set_val_in_hash);
+Datum
+set_val_in_hash(PG_FUNCTION_ARGS)
+{
+	TestDSMRegistryHashEntry *entry;
+	char	   *key = TextDatumGetCString(PG_GETARG_DATUM(0));
+	char	   *val = TextDatumGetCString(PG_GETARG_DATUM(1));
+	bool		found;
+
+	if (strlen(key) >= offsetof(TestDSMRegistryHashEntry, val))
+		ereport(ERROR,
+				(errmsg("key too long")));
+
+	tdr_attach_shmem();
+
+	entry = dshash_find_or_insert(tdr_hash, key, &found);
+	if (found)
+		dsa_free(tdr_dsa, entry->val);
+
+	entry->val = dsa_allocate(tdr_dsa, strlen(val) + 1);
+	strcpy(dsa_get_address(tdr_dsa, entry->val), val);
+
+	dshash_release_lock(tdr_hash, entry);
+
+	PG_RETURN_VOID();
+}
+
+PG_FUNCTION_INFO_V1(get_val_in_hash);
+Datum
+get_val_in_hash(PG_FUNCTION_ARGS)
+{
+	TestDSMRegistryHashEntry *entry;
+	char	   *key = TextDatumGetCString(PG_GETARG_DATUM(0));
+	text	   *val = NULL;
+
+	tdr_attach_shmem();
+
+	entry = dshash_find(tdr_hash, key, false);
+	if (entry == NULL)
+		PG_RETURN_NULL();
+
+	val = cstring_to_text(dsa_get_address(tdr_dsa, entry->val));
+
+	dshash_release_lock(tdr_hash, entry);
+
+	PG_RETURN_TEXT_P(val);
+}
diff --git a/src/test/perl/PostgreSQL/Test/AdjustUpgrade.pm b/src/test/perl/PostgreSQL/Test/AdjustUpgrade.pm
index 1725fe2f94871..7224c286e1df4 100644
--- a/src/test/perl/PostgreSQL/Test/AdjustUpgrade.pm
+++ b/src/test/perl/PostgreSQL/Test/AdjustUpgrade.pm
@@ -251,6 +251,32 @@ sub adjust_database_contents
 			'drop operator if exists public.=> (bigint, NONE)');
 	}
 
+	# Version 19 changed the output format of pg_lsn.  To avoid output
+	# differences, set all pg_lsn columns to NULL if the old version is
+	# older than 19.
+	if ($old_version < 19)
+	{
+		if ($old_version >= '9.5')
+		{
+			_add_st($result, 'regression',
+				"update brintest set lsncol = NULL");
+		}
+
+		if ($old_version >= 12)
+		{
+			_add_st($result, 'regression',
+				"update tab_core_types set pg_lsn = NULL");
+		}
+
+		if ($old_version >= 14)
+		{
+			_add_st($result, 'regression',
+				"update brintest_multi set lsncol = NULL");
+			_add_st($result, 'regression',
+				"update brintest_bloom set lsncol = NULL");
+		}
+	}
+
 	return $result;
 }
 
diff --git a/src/test/perl/PostgreSQL/Test/Cluster.pm b/src/test/perl/PostgreSQL/Test/Cluster.pm
index 49b2c86b29cbf..35413f140198b 100644
--- a/src/test/perl/PostgreSQL/Test/Cluster.pm
+++ b/src/test/perl/PostgreSQL/Test/Cluster.pm
@@ -290,6 +290,33 @@ sub connstr
 
 =pod
 
+=item $node->is_alive()
+
+Check if the node is alive, using pg_isready.
+Returns 1 if successful, 0 on failure.
+
+=cut
+
+sub is_alive
+{
+	my ($self) = @_;
+	local %ENV = $self->_get_env();
+
+	my $ret = PostgreSQL::Test::Utils::system_log(
+		'pg_isready',
+		'--timeout' => $PostgreSQL::Test::Utils::timeout_default,
+		'--host' => $self->host,
+		'--port' => $self->port);
+
+	if ($ret != 0)
+	{
+		return 0;
+	}
+	return 1;
+}
+
+=pod
+
 =item $node->raw_connect()
 
 Open a raw TCP or Unix domain socket connection to the server. This is
@@ -2199,6 +2226,14 @@ sub psql
 			$ret = $?;
 		};
 		my $exc_save = $@;
+
+		# we need a dummy $stderr from hereon, if we didn't collect it
+		if (! defined $stderr)
+		{
+			my $errtxt = "<not collected>";
+			$stderr = \$errtxt;
+		}
+
 		if ($exc_save)
 		{
 
diff --git a/src/test/perl/PostgreSQL/Test/Utils.pm b/src/test/perl/PostgreSQL/Test/Utils.pm
index 7d7ca83495f49..85d36a3171e25 100644
--- a/src/test/perl/PostgreSQL/Test/Utils.pm
+++ b/src/test/perl/PostgreSQL/Test/Utils.pm
@@ -108,6 +108,7 @@ BEGIN
 	delete $ENV{LANGUAGE};
 	delete $ENV{LC_ALL};
 	$ENV{LC_MESSAGES} = 'C';
+	$ENV{LC_NUMERIC} = 'C';
 	setlocale(LC_ALL, "");
 
 	# This list should be kept in sync with pg_regress.c.
diff --git a/src/test/recovery/meson.build b/src/test/recovery/meson.build
index 6e78ff1a030b3..52993c32dbba4 100644
--- a/src/test/recovery/meson.build
+++ b/src/test/recovery/meson.build
@@ -54,6 +54,7 @@ tests += {
       't/043_no_contrecord_switch.pl',
       't/044_invalidate_inactive_slots.pl',
       't/045_archive_restartpoint.pl',
+      't/046_checkpoint_logical_slot.pl',
       't/047_checkpoint_physical_slot.pl',
       't/048_vacuum_horizon_floor.pl'
     ],
diff --git a/src/test/recovery/t/003_recovery_targets.pl b/src/test/recovery/t/003_recovery_targets.pl
index 0ae2e98272709..f2109efa9b12d 100644
--- a/src/test/recovery/t/003_recovery_targets.pl
+++ b/src/test/recovery/t/003_recovery_targets.pl
@@ -187,4 +187,54 @@ sub test_recovery_standby
 	  qr/FATAL: .* recovery ended before configured recovery target was reached/,
 	'recovery end before target reached is a fatal error');
 
+# Invalid timeline target
+$node_standby = PostgreSQL::Test::Cluster->new('standby_9');
+$node_standby->init_from_backup($node_primary, 'my_backup',
+	has_restoring => 1);
+$node_standby->append_conf('postgresql.conf',
+	"recovery_target_timeline = 'bogus'");
+
+$res = run_log(
+	[
+		'pg_ctl',
+		'--pgdata' => $node_standby->data_dir,
+		'--log' => $node_standby->logfile,
+		'start',
+	]);
+ok(!$res, 'invalid timeline target (bogus value)');
+
+my $log_start = $node_standby->wait_for_log("is not a valid number");
+
+# Timeline target out of min range
+$node_standby->append_conf('postgresql.conf',
+	"recovery_target_timeline = '0'");
+
+$res = run_log(
+	[
+		'pg_ctl',
+		'--pgdata' => $node_standby->data_dir,
+		'--log' => $node_standby->logfile,
+		'start',
+	]);
+ok(!$res, 'invalid timeline target (lower bound check)');
+
+$log_start =
+  $node_standby->wait_for_log("must be between 1 and 4294967295", $log_start);
+
+# Timeline target out of max range
+$node_standby->append_conf('postgresql.conf',
+	"recovery_target_timeline = '4294967296'");
+
+$res = run_log(
+	[
+		'pg_ctl',
+		'--pgdata' => $node_standby->data_dir,
+		'--log' => $node_standby->logfile,
+		'start',
+	]);
+ok(!$res, 'invalid timeline target (upper bound check)');
+
+$log_start =
+  $node_standby->wait_for_log("must be between 1 and 4294967295", $log_start);
+
 done_testing();
diff --git a/src/test/recovery/t/013_crash_restart.pl b/src/test/recovery/t/013_crash_restart.pl
index debfa635c36fe..4c5af018ee44e 100644
--- a/src/test/recovery/t/013_crash_restart.pl
+++ b/src/test/recovery/t/013_crash_restart.pl
@@ -228,6 +228,13 @@
 	'before-orderly-restart',
 	'can still write after crash restart');
 
+# Confirm that the logical replication launcher, a background worker
+# without the never-restart flag, has also restarted successfully.
+is($node->poll_query_until('postgres',
+	"SELECT count(*) = 1 FROM pg_stat_activity WHERE backend_type = 'logical replication launcher'"),
+	'1',
+	'logical replication launcher restarted after crash');
+
 # Just to be sure, check that an orderly restart now still works
 $node->restart();
 
diff --git a/src/test/recovery/t/016_min_consistency.pl b/src/test/recovery/t/016_min_consistency.pl
index 9a3b4866fce4a..b381d0c21b5fe 100644
--- a/src/test/recovery/t/016_min_consistency.pl
+++ b/src/test/recovery/t/016_min_consistency.pl
@@ -39,7 +39,7 @@ sub find_largest_lsn
 	defined($len) or die "read error on $filename: $!";
 	close($fh);
 
-	return sprintf("%X/%X", $max_hi, $max_lo);
+	return sprintf("%X/%08X", $max_hi, $max_lo);
 }
 
 # Initialize primary node
diff --git a/src/test/recovery/t/027_stream_regress.pl b/src/test/recovery/t/027_stream_regress.pl
index 83def062d11e1..5d2c06ba06e73 100644
--- a/src/test/recovery/t/027_stream_regress.pl
+++ b/src/test/recovery/t/027_stream_regress.pl
@@ -81,7 +81,14 @@
 	  . "--max-concurrent-tests=20 "
 	  . "--inputdir=../regress "
 	  . "--outputdir=\"$outputdir\"");
-if ($rc != 0)
+
+# Regression diffs are only meaningful if both the primary and the standby
+# are still alive after a regression test failure.  A crash would cause a
+# useless increase in the log quantity, mostly filled with information
+# related to queries that could not run.
+my $primary_alive = $node_primary->is_alive;
+my $standby_alive = $node_standby_1->is_alive;
+if ($rc != 0 && $primary_alive && $standby_alive)
 {
 	# Dump out the regression diffs file, if there is one
 	my $diffs = "$outputdir/regression.diffs";
@@ -93,6 +100,8 @@
 	}
 }
 is($rc, 0, 'regression tests pass');
+is($primary_alive, 1, 'primary alive after regression test run');
+is($standby_alive, 1, 'standby alive after regression test run');
 
 # Clobber all sequences with their next value, so that we don't have
 # differences between nodes due to caching.
diff --git a/src/test/recovery/t/035_standby_logical_decoding.pl b/src/test/recovery/t/035_standby_logical_decoding.pl
index 921813483e37c..c9c182892cf84 100644
--- a/src/test/recovery/t/035_standby_logical_decoding.pl
+++ b/src/test/recovery/t/035_standby_logical_decoding.pl
@@ -8,6 +8,7 @@
 
 use PostgreSQL::Test::Cluster;
 use PostgreSQL::Test::Utils;
+use Time::HiRes qw(usleep);
 use Test::More;
 
 if ($ENV{enable_injection_points} ne 'yes')
@@ -623,7 +624,7 @@ sub wait_until_vacuum_can_remove
 	  /ERROR:  cannot copy invalidated replication slot "vacuum_full_inactiveslot"/,
 	"invalidated slot cannot be copied");
 
-# Turn hot_standby_feedback back on
+# Set hot_standby_feedback to on
 change_hot_standby_feedback_and_wait_for_xmins(1, 1);
 
 ##################################################
@@ -754,12 +755,12 @@ sub wait_until_vacuum_can_remove
 
 # message should not be issued
 ok( !$node_standby->log_contains(
-		"invalidating obsolete slot \"no_conflict_inactiveslot\"", $logstart),
+		"invalidating obsolete replication slot \"no_conflict_inactiveslot\"", $logstart),
 	'inactiveslot slot invalidation is not logged with vacuum on conflict_test'
 );
 
 ok( !$node_standby->log_contains(
-		"invalidating obsolete slot \"no_conflict_activeslot\"", $logstart),
+		"invalidating obsolete replication slot \"no_conflict_activeslot\"", $logstart),
 	'activeslot slot invalidation is not logged with vacuum on conflict_test'
 );
 
diff --git a/src/test/recovery/t/041_checkpoint_at_promote.pl b/src/test/recovery/t/041_checkpoint_at_promote.pl
index cb63ac8d5c9b0..12750ff7d4f33 100644
--- a/src/test/recovery/t/041_checkpoint_at_promote.pl
+++ b/src/test/recovery/t/041_checkpoint_at_promote.pl
@@ -91,7 +91,7 @@
 # Check the logs that the restart point has started on standby.  This is
 # optional, but let's be sure.
 ok( $node_standby->log_contains(
-		"restartpoint starting: immediate wait", $logstart),
+		"restartpoint starting: fast wait", $logstart),
 	"restartpoint has started");
 
 # Trigger promotion during the restart point.
diff --git a/src/test/recovery/t/046_checkpoint_logical_slot.pl b/src/test/recovery/t/046_checkpoint_logical_slot.pl
new file mode 100644
index 0000000000000..4fd709e3a0312
--- /dev/null
+++ b/src/test/recovery/t/046_checkpoint_logical_slot.pl
@@ -0,0 +1,142 @@
+# Copyright (c) 2025, PostgreSQL Global Development Group
+#
+# This test verifies the case when the logical slot is advanced during
+# checkpoint. The test checks that the logical slot's restart_lsn still refers
+# to an existed WAL segment after immediate restart.
+#
+use strict;
+use warnings FATAL => 'all';
+
+use PostgreSQL::Test::Cluster;
+use PostgreSQL::Test::Utils;
+
+use Test::More;
+
+if ($ENV{enable_injection_points} ne 'yes')
+{
+	plan skip_all => 'Injection points not supported by this build';
+}
+
+my ($node, $result);
+
+$node = PostgreSQL::Test::Cluster->new('mike');
+$node->init;
+$node->append_conf('postgresql.conf', "wal_level = 'logical'");
+$node->start;
+
+# Check if the extension injection_points is available, as it may be
+# possible that this script is run with installcheck, where the module
+# would not be installed by default.
+if (!$node->check_extension('injection_points'))
+{
+	plan skip_all => 'Extension injection_points not installed';
+}
+
+$node->safe_psql('postgres', q(CREATE EXTENSION injection_points));
+
+# Create the two slots we'll need.
+$node->safe_psql('postgres',
+	q{select pg_create_logical_replication_slot('slot_logical', 'test_decoding')}
+);
+$node->safe_psql('postgres',
+	q{select pg_create_physical_replication_slot('slot_physical', true)});
+
+# Advance both slots to the current position just to have everything "valid".
+$node->safe_psql('postgres',
+	q{select count(*) from pg_logical_slot_get_changes('slot_logical', null, null)}
+);
+$node->safe_psql('postgres',
+	q{select pg_replication_slot_advance('slot_physical', pg_current_wal_lsn())}
+);
+
+# Run checkpoint to flush current state to disk and set a baseline.
+$node->safe_psql('postgres', q{checkpoint});
+
+# Generate some transactions to get RUNNING_XACTS.
+my $xacts = $node->background_psql('postgres');
+$xacts->query_until(
+	qr/run_xacts/,
+	q(\echo run_xacts
+SELECT 1 \watch 0.1
+\q
+));
+
+$node->advance_wal(20);
+
+# Run another checkpoint to set a new restore LSN.
+$node->safe_psql('postgres', q{checkpoint});
+
+$node->advance_wal(20);
+
+# Run another checkpoint, this time in the background, and make it wait
+# on the injection point) so that the checkpoint stops right before
+# removing old WAL segments.
+note('starting checkpoint');
+
+my $checkpoint = $node->background_psql('postgres');
+$checkpoint->query_safe(
+	q(select injection_points_attach('checkpoint-before-old-wal-removal','wait'))
+);
+$checkpoint->query_until(
+	qr/starting_checkpoint/,
+	q(\echo starting_checkpoint
+checkpoint;
+\q
+));
+
+# Wait until the checkpoint stops right before removing WAL segments.
+note('waiting for injection_point');
+$node->wait_for_event('checkpointer', 'checkpoint-before-old-wal-removal');
+note('injection_point is reached');
+
+# Try to advance the logical slot, but make it stop when it moves to the next
+# WAL segment (this has to happen in the background, too).
+my $logical = $node->background_psql('postgres');
+$logical->query_safe(
+	q{select injection_points_attach('logical-replication-slot-advance-segment','wait');}
+);
+$logical->query_until(
+	qr/get_changes/,
+	q(
+\echo get_changes
+select count(*) from pg_logical_slot_get_changes('slot_logical', null, null) \watch 1
+\q
+));
+
+# Wait until the slot's restart_lsn points to the next WAL segment.
+note('waiting for injection_point');
+$node->wait_for_event('client backend',
+	'logical-replication-slot-advance-segment');
+note('injection_point is reached');
+
+# OK, we're in the right situation: time to advance the physical slot, which
+# recalculates the required LSN, and then unblock the checkpoint, which
+# removes the WAL still needed by the logical slot.
+$node->safe_psql('postgres',
+	q{select pg_replication_slot_advance('slot_physical', pg_current_wal_lsn())}
+);
+
+# Generate a long WAL record, spawning at least two pages for the follow-up
+# post-recovery check.
+$node->safe_psql('postgres',
+	q{select pg_logical_emit_message(false, '', repeat('123456789', 1000))});
+
+# Continue the checkpoint and wait for its completion.
+my $log_offset = -s $node->logfile;
+$node->safe_psql('postgres',
+	q{select injection_points_wakeup('checkpoint-before-old-wal-removal')});
+$node->wait_for_log(qr/checkpoint complete/, $log_offset);
+
+# Abruptly stop the server.
+$node->stop('immediate');
+
+$node->start;
+
+eval {
+	$node->safe_psql('postgres',
+		q{select count(*) from pg_logical_slot_get_changes('slot_logical', null, null);}
+	);
+};
+is($@, '', "Logical slot still valid");
+
+done_testing();
diff --git a/src/test/recovery/t/047_checkpoint_physical_slot.pl b/src/test/recovery/t/047_checkpoint_physical_slot.pl
index a1332b5d44cbe..9e98383e30ea9 100644
--- a/src/test/recovery/t/047_checkpoint_physical_slot.pl
+++ b/src/test/recovery/t/047_checkpoint_physical_slot.pl
@@ -94,9 +94,11 @@
 	q{select pg_replication_slot_advance('slot_physical', pg_current_wal_lsn())}
 );
 
-# Continue the checkpoint.
+# Continue the checkpoint and wait for its completion.
+my $log_offset = -s $node->logfile;
 $node->safe_psql('postgres',
 	q{select injection_points_wakeup('checkpoint-before-old-wal-removal')});
+$node->wait_for_log(qr/checkpoint complete/, $log_offset);
 
 my $restart_lsn_old = $node->safe_psql('postgres',
 	q{select restart_lsn from pg_replication_slots where slot_name = 'slot_physical'}
@@ -104,8 +106,7 @@
 chomp($restart_lsn_old);
 note("restart lsn before stop: $restart_lsn_old");
 
-# Abruptly stop the server (1 second should be enough for the checkpoint
-# to finish; it would be better).
+# Abruptly stop the server.
 $node->stop('immediate');
 
 $node->start;
diff --git a/src/test/regress/expected/alter_table.out b/src/test/regress/expected/alter_table.out
index 750efc042d8ee..08984dd98f168 100644
--- a/src/test/regress/expected/alter_table.out
+++ b/src/test/regress/expected/alter_table.out
@@ -4750,6 +4750,14 @@ create table attbl(a int);
 create table atref(b attbl check ((b).a is not null));
 alter table attbl alter column a type numeric;  -- someday this should work
 ERROR:  cannot alter table "attbl" because column "atref.b" uses its row type
+alter table atref drop constraint atref_b_check;
+create statistics atref_stat on ((b).a is not null) from atref;
+alter table attbl alter column a type numeric;  -- someday this should work
+ERROR:  cannot alter table "attbl" because column "atref.b" uses its row type
+drop statistics atref_stat;
+create index atref_idx on atref (((b).a));
+alter table attbl alter column a type numeric;  -- someday this should work
+ERROR:  cannot alter table "attbl" because column "atref.b" uses its row type
 drop table attbl, atref;
 /* End test case for bug #18970 */
 -- Test that ALTER TABLE rewrite preserves a clustered index
diff --git a/src/test/regress/expected/btree_index.out b/src/test/regress/expected/btree_index.out
index bfb1a286ea4ad..21dc9b5783a7c 100644
--- a/src/test/regress/expected/btree_index.out
+++ b/src/test/regress/expected/btree_index.out
@@ -195,54 +195,123 @@ ORDER BY proname DESC, proargtypes DESC, pronamespace DESC LIMIT 1;
 (1 row)
 
 --
--- Add coverage for RowCompare quals whose rhs row has a NULL that ends scan
+-- Forwards scan RowCompare qual whose row arg has a NULL that affects our
+-- initial positioning strategy
 --
 explain (costs off)
 SELECT proname, proargtypes, pronamespace
    FROM pg_proc
-   WHERE proname = 'abs' AND (proname, proargtypes) < ('abs', NULL)
+   WHERE (proname, proargtypes) >= ('abs', NULL) AND proname <= 'abs'
 ORDER BY proname, proargtypes, pronamespace;
-                                                 QUERY PLAN                                                  
--------------------------------------------------------------------------------------------------------------
+                                                  QUERY PLAN                                                   
+---------------------------------------------------------------------------------------------------------------
  Index Only Scan using pg_proc_proname_args_nsp_index on pg_proc
-   Index Cond: ((ROW(proname, proargtypes) < ROW('abs'::name, NULL::oidvector)) AND (proname = 'abs'::name))
+   Index Cond: ((ROW(proname, proargtypes) >= ROW('abs'::name, NULL::oidvector)) AND (proname <= 'abs'::name))
 (2 rows)
 
 SELECT proname, proargtypes, pronamespace
    FROM pg_proc
-   WHERE proname = 'abs' AND (proname, proargtypes) < ('abs', NULL)
+   WHERE (proname, proargtypes) >= ('abs', NULL) AND proname <= 'abs'
 ORDER BY proname, proargtypes, pronamespace;
  proname | proargtypes | pronamespace 
 ---------+-------------+--------------
 (0 rows)
 
 --
--- Add coverage for backwards scan RowCompare quals whose rhs row has a NULL
--- that ends scan
+-- Forwards scan RowCompare quals whose row arg has a NULL that ends scan
 --
 explain (costs off)
 SELECT proname, proargtypes, pronamespace
    FROM pg_proc
-   WHERE proname = 'abs' AND (proname, proargtypes) > ('abs', NULL)
+   WHERE proname >= 'abs' AND (proname, proargtypes) < ('abs', NULL)
+ORDER BY proname, proargtypes, pronamespace;
+                                                  QUERY PLAN                                                  
+--------------------------------------------------------------------------------------------------------------
+ Index Only Scan using pg_proc_proname_args_nsp_index on pg_proc
+   Index Cond: ((proname >= 'abs'::name) AND (ROW(proname, proargtypes) < ROW('abs'::name, NULL::oidvector)))
+(2 rows)
+
+SELECT proname, proargtypes, pronamespace
+   FROM pg_proc
+   WHERE proname >= 'abs' AND (proname, proargtypes) < ('abs', NULL)
+ORDER BY proname, proargtypes, pronamespace;
+ proname | proargtypes | pronamespace 
+---------+-------------+--------------
+(0 rows)
+
+--
+-- Backwards scan RowCompare qual whose row arg has a NULL that affects our
+-- initial positioning strategy
+--
+explain (costs off)
+SELECT proname, proargtypes, pronamespace
+   FROM pg_proc
+   WHERE proname >= 'abs' AND (proname, proargtypes) <= ('abs', NULL)
+ORDER BY proname DESC, proargtypes DESC, pronamespace DESC;
+                                                  QUERY PLAN                                                   
+---------------------------------------------------------------------------------------------------------------
+ Index Only Scan Backward using pg_proc_proname_args_nsp_index on pg_proc
+   Index Cond: ((proname >= 'abs'::name) AND (ROW(proname, proargtypes) <= ROW('abs'::name, NULL::oidvector)))
+(2 rows)
+
+SELECT proname, proargtypes, pronamespace
+   FROM pg_proc
+   WHERE proname >= 'abs' AND (proname, proargtypes) <= ('abs', NULL)
+ORDER BY proname DESC, proargtypes DESC, pronamespace DESC;
+ proname | proargtypes | pronamespace 
+---------+-------------+--------------
+(0 rows)
+
+--
+-- Backwards scan RowCompare qual whose row arg has a NULL that ends scan
+--
+explain (costs off)
+SELECT proname, proargtypes, pronamespace
+   FROM pg_proc
+   WHERE (proname, proargtypes) > ('abs', NULL) AND proname <= 'abs'
 ORDER BY proname DESC, proargtypes DESC, pronamespace DESC;
-                                                 QUERY PLAN                                                  
--------------------------------------------------------------------------------------------------------------
+                                                  QUERY PLAN                                                  
+--------------------------------------------------------------------------------------------------------------
  Index Only Scan Backward using pg_proc_proname_args_nsp_index on pg_proc
-   Index Cond: ((ROW(proname, proargtypes) > ROW('abs'::name, NULL::oidvector)) AND (proname = 'abs'::name))
+   Index Cond: ((ROW(proname, proargtypes) > ROW('abs'::name, NULL::oidvector)) AND (proname <= 'abs'::name))
 (2 rows)
 
 SELECT proname, proargtypes, pronamespace
    FROM pg_proc
-   WHERE proname = 'abs' AND (proname, proargtypes) > ('abs', NULL)
+   WHERE (proname, proargtypes) > ('abs', NULL) AND proname <= 'abs'
 ORDER BY proname DESC, proargtypes DESC, pronamespace DESC;
  proname | proargtypes | pronamespace 
 ---------+-------------+--------------
 (0 rows)
 
+-- Makes B-Tree preprocessing deal with unmarking redundant keys that were
+-- initially marked required (test case relies on current row compare
+-- preprocessing limitations)
+explain (costs off)
+SELECT proname, proargtypes, pronamespace
+   FROM pg_proc
+   WHERE proname = 'zzzzzz' AND (proname, proargtypes) > ('abs', NULL)
+   AND pronamespace IN (1, 2, 3) AND proargtypes IN ('26 23', '5077')
+ORDER BY proname, proargtypes, pronamespace;
+                                                                                                     QUERY PLAN                                                                                                     
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+ Index Only Scan using pg_proc_proname_args_nsp_index on pg_proc
+   Index Cond: ((ROW(proname, proargtypes) > ROW('abs'::name, NULL::oidvector)) AND (proname = 'zzzzzz'::name) AND (proargtypes = ANY ('{"26 23",5077}'::oidvector[])) AND (pronamespace = ANY ('{1,2,3}'::oid[])))
+(2 rows)
+
+SELECT proname, proargtypes, pronamespace
+   FROM pg_proc
+   WHERE proname = 'zzzzzz' AND (proname, proargtypes) > ('abs', NULL)
+   AND pronamespace IN (1, 2, 3) AND proargtypes IN ('26 23', '5077')
+ORDER BY proname, proargtypes, pronamespace;
+ proname | proargtypes | pronamespace 
+---------+-------------+--------------
+(0 rows)
+
 --
--- Add coverage for recheck of > key following array advancement on previous
--- (left sibling) page that used a high key whose attribute value corresponding
--- to the > key was -inf (due to being truncated when the high key was created).
+-- Performs a recheck of > key following array advancement on previous (left
+-- sibling) page that used a high key whose attribute value corresponding to
+-- the > key was -inf (due to being truncated when the high key was created).
 --
 -- XXX This relies on the assumption that tenk1_thous_tenthous has a truncated
 -- high key "(183, -inf)" on the first page that we'll scan.  The test will only
diff --git a/src/test/regress/expected/compression.out b/src/test/regress/expected/compression.out
index 4dd9ee7200d18..09f198149aa4f 100644
--- a/src/test/regress/expected/compression.out
+++ b/src/test/regress/expected/compression.out
@@ -1,3 +1,7 @@
+-- Default set of tests for TOAST compression, independent on compression
+-- methods supported by the build.
+CREATE SCHEMA pglz;
+SET search_path TO pglz, public;
 \set HIDE_TOAST_COMPRESSION false
 -- ensure we get stable results regardless of installation's default
 SET default_toast_compression = 'pglz';
@@ -6,21 +10,13 @@ CREATE TABLE cmdata(f1 text COMPRESSION pglz);
 CREATE INDEX idx ON cmdata(f1);
 INSERT INTO cmdata VALUES(repeat('1234567890', 1000));
 \d+ cmdata
-                                        Table "public.cmdata"
+                                         Table "pglz.cmdata"
  Column | Type | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
 --------+------+-----------+----------+---------+----------+-------------+--------------+-------------
  f1     | text |           |          |         | extended | pglz        |              | 
 Indexes:
     "idx" btree (f1)
 
-CREATE TABLE cmdata1(f1 TEXT COMPRESSION lz4);
-INSERT INTO cmdata1 VALUES(repeat('1234567890', 1004));
-\d+ cmdata1
-                                        Table "public.cmdata1"
- Column | Type | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
---------+------+-----------+----------+---------+----------+-------------+--------------+-------------
- f1     | text |           |          |         | extended | lz4         |              | 
-
 -- verify stored compression method in the data
 SELECT pg_column_compression(f1) FROM cmdata;
  pg_column_compression 
@@ -28,12 +24,6 @@ SELECT pg_column_compression(f1) FROM cmdata;
  pglz
 (1 row)
 
-SELECT pg_column_compression(f1) FROM cmdata1;
- pg_column_compression 
------------------------
- lz4
-(1 row)
-
 -- decompress data slice
 SELECT SUBSTR(f1, 200, 5) FROM cmdata;
  substr 
@@ -41,16 +31,10 @@ SELECT SUBSTR(f1, 200, 5) FROM cmdata;
  01234
 (1 row)
 
-SELECT SUBSTR(f1, 2000, 50) FROM cmdata1;
-                       substr                       
-----------------------------------------------------
- 01234567890123456789012345678901234567890123456789
-(1 row)
-
 -- copy with table creation
 SELECT * INTO cmmove1 FROM cmdata;
 \d+ cmmove1
-                                        Table "public.cmmove1"
+                                         Table "pglz.cmmove1"
  Column | Type | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
 --------+------+-----------+----------+---------+----------+-------------+--------------+-------------
  f1     | text |           |          |         | extended |             |              | 
@@ -61,45 +45,9 @@ SELECT pg_column_compression(f1) FROM cmmove1;
  pglz
 (1 row)
 
--- copy to existing table
-CREATE TABLE cmmove3(f1 text COMPRESSION pglz);
-INSERT INTO cmmove3 SELECT * FROM cmdata;
-INSERT INTO cmmove3 SELECT * FROM cmdata1;
-SELECT pg_column_compression(f1) FROM cmmove3;
- pg_column_compression 
------------------------
- pglz
- lz4
-(2 rows)
-
--- test LIKE INCLUDING COMPRESSION
-CREATE TABLE cmdata2 (LIKE cmdata1 INCLUDING COMPRESSION);
-\d+ cmdata2
-                                        Table "public.cmdata2"
- Column | Type | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
---------+------+-----------+----------+---------+----------+-------------+--------------+-------------
- f1     | text |           |          |         | extended | lz4         |              | 
-
-DROP TABLE cmdata2;
 -- try setting compression for incompressible data type
 CREATE TABLE cmdata2 (f1 int COMPRESSION pglz);
 ERROR:  column data type integer does not support compression
--- update using datum from different table
-CREATE TABLE cmmove2(f1 text COMPRESSION pglz);
-INSERT INTO cmmove2 VALUES (repeat('1234567890', 1004));
-SELECT pg_column_compression(f1) FROM cmmove2;
- pg_column_compression 
------------------------
- pglz
-(1 row)
-
-UPDATE cmmove2 SET f1 = cmdata1.f1 FROM cmdata1;
-SELECT pg_column_compression(f1) FROM cmmove2;
- pg_column_compression 
------------------------
- lz4
-(1 row)
-
 -- test externally stored compressed data
 CREATE OR REPLACE FUNCTION large_val() RETURNS TEXT LANGUAGE SQL AS
 'select array_agg(fipshash(g::text))::text from generate_series(1, 256) g';
@@ -111,21 +59,6 @@ SELECT pg_column_compression(f1) FROM cmdata2;
  pglz
 (1 row)
 
-INSERT INTO cmdata1 SELECT large_val() || repeat('a', 4000);
-SELECT pg_column_compression(f1) FROM cmdata1;
- pg_column_compression 
------------------------
- lz4
- lz4
-(2 rows)
-
-SELECT SUBSTR(f1, 200, 5) FROM cmdata1;
- substr 
---------
- 01234
- 79026
-(2 rows)
-
 SELECT SUBSTR(f1, 200, 5) FROM cmdata2;
  substr 
 --------
@@ -136,21 +69,21 @@ DROP TABLE cmdata2;
 --test column type update varlena/non-varlena
 CREATE TABLE cmdata2 (f1 int);
 \d+ cmdata2
-                                         Table "public.cmdata2"
+                                          Table "pglz.cmdata2"
  Column |  Type   | Collation | Nullable | Default | Storage | Compression | Stats target | Description 
 --------+---------+-----------+----------+---------+---------+-------------+--------------+-------------
  f1     | integer |           |          |         | plain   |             |              | 
 
 ALTER TABLE cmdata2 ALTER COLUMN f1 TYPE varchar;
 \d+ cmdata2
-                                              Table "public.cmdata2"
+                                               Table "pglz.cmdata2"
  Column |       Type        | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
 --------+-------------------+-----------+----------+---------+----------+-------------+--------------+-------------
  f1     | character varying |           |          |         | extended |             |              | 
 
 ALTER TABLE cmdata2 ALTER COLUMN f1 TYPE int USING f1::integer;
 \d+ cmdata2
-                                         Table "public.cmdata2"
+                                          Table "pglz.cmdata2"
  Column |  Type   | Collation | Nullable | Default | Storage | Compression | Stats target | Description 
 --------+---------+-----------+----------+---------+---------+-------------+--------------+-------------
  f1     | integer |           |          |         | plain   |             |              | 
@@ -160,14 +93,14 @@ ALTER TABLE cmdata2 ALTER COLUMN f1 TYPE int USING f1::integer;
 ALTER TABLE cmdata2 ALTER COLUMN f1 TYPE varchar;
 ALTER TABLE cmdata2 ALTER COLUMN f1 SET COMPRESSION pglz;
 \d+ cmdata2
-                                              Table "public.cmdata2"
+                                               Table "pglz.cmdata2"
  Column |       Type        | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
 --------+-------------------+-----------+----------+---------+----------+-------------+--------------+-------------
  f1     | character varying |           |          |         | extended | pglz        |              | 
 
 ALTER TABLE cmdata2 ALTER COLUMN f1 SET STORAGE plain;
 \d+ cmdata2
-                                              Table "public.cmdata2"
+                                               Table "pglz.cmdata2"
  Column |       Type        | Collation | Nullable | Default | Storage | Compression | Stats target | Description 
 --------+-------------------+-----------+----------+---------+---------+-------------+--------------+-------------
  f1     | character varying |           |          |         | plain   | pglz        |              | 
@@ -179,164 +112,47 @@ SELECT pg_column_compression(f1) FROM cmdata2;
  
 (1 row)
 
--- test compression with materialized view
-CREATE MATERIALIZED VIEW compressmv(x) AS SELECT * FROM cmdata1;
-\d+ compressmv
-                                Materialized view "public.compressmv"
- Column | Type | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
---------+------+-----------+----------+---------+----------+-------------+--------------+-------------
- x      | text |           |          |         | extended |             |              | 
-View definition:
- SELECT f1 AS x
-   FROM cmdata1;
-
-SELECT pg_column_compression(f1) FROM cmdata1;
- pg_column_compression 
------------------------
- lz4
- lz4
-(2 rows)
-
-SELECT pg_column_compression(x) FROM compressmv;
- pg_column_compression 
------------------------
- lz4
- lz4
-(2 rows)
-
--- test compression with partition
-CREATE TABLE cmpart(f1 text COMPRESSION lz4) PARTITION BY HASH(f1);
-CREATE TABLE cmpart1 PARTITION OF cmpart FOR VALUES WITH (MODULUS 2, REMAINDER 0);
-CREATE TABLE cmpart2(f1 text COMPRESSION pglz);
-ALTER TABLE cmpart ATTACH PARTITION cmpart2 FOR VALUES WITH (MODULUS 2, REMAINDER 1);
-INSERT INTO cmpart VALUES (repeat('123456789', 1004));
-INSERT INTO cmpart VALUES (repeat('123456789', 4004));
-SELECT pg_column_compression(f1) FROM cmpart1;
- pg_column_compression 
------------------------
- lz4
-(1 row)
-
-SELECT pg_column_compression(f1) FROM cmpart2;
- pg_column_compression 
------------------------
- pglz
-(1 row)
-
 -- test compression with inheritance
-CREATE TABLE cminh() INHERITS(cmdata, cmdata1); -- error
-NOTICE:  merging multiple inherited definitions of column "f1"
-ERROR:  column "f1" has a compression method conflict
-DETAIL:  pglz versus lz4
-CREATE TABLE cminh(f1 TEXT COMPRESSION lz4) INHERITS(cmdata); -- error
-NOTICE:  merging column "f1" with inherited definition
-ERROR:  column "f1" has a compression method conflict
-DETAIL:  pglz versus lz4
 CREATE TABLE cmdata3(f1 text);
 CREATE TABLE cminh() INHERITS (cmdata, cmdata3);
 NOTICE:  merging multiple inherited definitions of column "f1"
 -- test default_toast_compression GUC
+-- suppress machine-dependent details
+\set VERBOSITY terse
 SET default_toast_compression = '';
 ERROR:  invalid value for parameter "default_toast_compression": ""
-HINT:  Available values: pglz, lz4.
 SET default_toast_compression = 'I do not exist compression';
 ERROR:  invalid value for parameter "default_toast_compression": "I do not exist compression"
-HINT:  Available values: pglz, lz4.
-SET default_toast_compression = 'lz4';
 SET default_toast_compression = 'pglz';
--- test alter compression method
-ALTER TABLE cmdata ALTER COLUMN f1 SET COMPRESSION lz4;
-INSERT INTO cmdata VALUES (repeat('123456789', 4004));
-\d+ cmdata
-                                        Table "public.cmdata"
- Column | Type | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
---------+------+-----------+----------+---------+----------+-------------+--------------+-------------
- f1     | text |           |          |         | extended | lz4         |              | 
-Indexes:
-    "idx" btree (f1)
-Child tables: cminh
-
-SELECT pg_column_compression(f1) FROM cmdata;
- pg_column_compression 
------------------------
- pglz
- lz4
-(2 rows)
-
+\set VERBOSITY default
 ALTER TABLE cmdata2 ALTER COLUMN f1 SET COMPRESSION default;
 \d+ cmdata2
-                                              Table "public.cmdata2"
+                                               Table "pglz.cmdata2"
  Column |       Type        | Collation | Nullable | Default | Storage | Compression | Stats target | Description 
 --------+-------------------+-----------+----------+---------+---------+-------------+--------------+-------------
  f1     | character varying |           |          |         | plain   |             |              | 
 
--- test alter compression method for materialized views
-ALTER MATERIALIZED VIEW compressmv ALTER COLUMN x SET COMPRESSION lz4;
-\d+ compressmv
-                                Materialized view "public.compressmv"
- Column | Type | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
---------+------+-----------+----------+---------+----------+-------------+--------------+-------------
- x      | text |           |          |         | extended | lz4         |              | 
-View definition:
- SELECT f1 AS x
-   FROM cmdata1;
-
--- test alter compression method for partitioned tables
-ALTER TABLE cmpart1 ALTER COLUMN f1 SET COMPRESSION pglz;
-ALTER TABLE cmpart2 ALTER COLUMN f1 SET COMPRESSION lz4;
--- new data should be compressed with the current compression method
-INSERT INTO cmpart VALUES (repeat('123456789', 1004));
-INSERT INTO cmpart VALUES (repeat('123456789', 4004));
-SELECT pg_column_compression(f1) FROM cmpart1;
- pg_column_compression 
------------------------
- lz4
- pglz
-(2 rows)
-
-SELECT pg_column_compression(f1) FROM cmpart2;
- pg_column_compression 
------------------------
- pglz
- lz4
-(2 rows)
-
+DROP TABLE cmdata2;
 -- VACUUM FULL does not recompress
 SELECT pg_column_compression(f1) FROM cmdata;
  pg_column_compression 
 -----------------------
  pglz
- lz4
-(2 rows)
+(1 row)
 
 VACUUM FULL cmdata;
 SELECT pg_column_compression(f1) FROM cmdata;
  pg_column_compression 
 -----------------------
  pglz
- lz4
-(2 rows)
+(1 row)
 
--- test expression index
-DROP TABLE cmdata2;
-CREATE TABLE cmdata2 (f1 TEXT COMPRESSION pglz, f2 TEXT COMPRESSION lz4);
-CREATE UNIQUE INDEX idx1 ON cmdata2 ((f1 || f2));
-INSERT INTO cmdata2 VALUES((SELECT array_agg(fipshash(g::TEXT))::TEXT FROM
-generate_series(1, 50) g), VERSION());
 -- check data is ok
 SELECT length(f1) FROM cmdata;
  length 
 --------
   10000
-  36036
-(2 rows)
-
-SELECT length(f1) FROM cmdata1;
- length 
---------
-  10040
-  12449
-(2 rows)
+(1 row)
 
 SELECT length(f1) FROM cmmove1;
  length 
@@ -344,19 +160,6 @@ SELECT length(f1) FROM cmmove1;
   10000
 (1 row)
 
-SELECT length(f1) FROM cmmove2;
- length 
---------
-  10040
-(1 row)
-
-SELECT length(f1) FROM cmmove3;
- length 
---------
-  10000
-  10040
-(2 rows)
-
 CREATE TABLE badcompresstbl (a text COMPRESSION I_Do_Not_Exist_Compression); -- fails
 ERROR:  invalid compression method "i_do_not_exist_compression"
 CREATE TABLE badcompresstbl (a text);
diff --git a/src/test/regress/expected/compression_1.out b/src/test/regress/expected/compression_1.out
deleted file mode 100644
index 7bd7642b4b94f..0000000000000
--- a/src/test/regress/expected/compression_1.out
+++ /dev/null
@@ -1,360 +0,0 @@
-\set HIDE_TOAST_COMPRESSION false
--- ensure we get stable results regardless of installation's default
-SET default_toast_compression = 'pglz';
--- test creating table with compression method
-CREATE TABLE cmdata(f1 text COMPRESSION pglz);
-CREATE INDEX idx ON cmdata(f1);
-INSERT INTO cmdata VALUES(repeat('1234567890', 1000));
-\d+ cmdata
-                                        Table "public.cmdata"
- Column | Type | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
---------+------+-----------+----------+---------+----------+-------------+--------------+-------------
- f1     | text |           |          |         | extended | pglz        |              | 
-Indexes:
-    "idx" btree (f1)
-
-CREATE TABLE cmdata1(f1 TEXT COMPRESSION lz4);
-ERROR:  compression method lz4 not supported
-DETAIL:  This functionality requires the server to be built with lz4 support.
-INSERT INTO cmdata1 VALUES(repeat('1234567890', 1004));
-ERROR:  relation "cmdata1" does not exist
-LINE 1: INSERT INTO cmdata1 VALUES(repeat('1234567890', 1004));
-                    ^
-\d+ cmdata1
--- verify stored compression method in the data
-SELECT pg_column_compression(f1) FROM cmdata;
- pg_column_compression 
------------------------
- pglz
-(1 row)
-
-SELECT pg_column_compression(f1) FROM cmdata1;
-ERROR:  relation "cmdata1" does not exist
-LINE 1: SELECT pg_column_compression(f1) FROM cmdata1;
-                                              ^
--- decompress data slice
-SELECT SUBSTR(f1, 200, 5) FROM cmdata;
- substr 
---------
- 01234
-(1 row)
-
-SELECT SUBSTR(f1, 2000, 50) FROM cmdata1;
-ERROR:  relation "cmdata1" does not exist
-LINE 1: SELECT SUBSTR(f1, 2000, 50) FROM cmdata1;
-                                         ^
--- copy with table creation
-SELECT * INTO cmmove1 FROM cmdata;
-\d+ cmmove1
-                                        Table "public.cmmove1"
- Column | Type | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
---------+------+-----------+----------+---------+----------+-------------+--------------+-------------
- f1     | text |           |          |         | extended |             |              | 
-
-SELECT pg_column_compression(f1) FROM cmmove1;
- pg_column_compression 
------------------------
- pglz
-(1 row)
-
--- copy to existing table
-CREATE TABLE cmmove3(f1 text COMPRESSION pglz);
-INSERT INTO cmmove3 SELECT * FROM cmdata;
-INSERT INTO cmmove3 SELECT * FROM cmdata1;
-ERROR:  relation "cmdata1" does not exist
-LINE 1: INSERT INTO cmmove3 SELECT * FROM cmdata1;
-                                          ^
-SELECT pg_column_compression(f1) FROM cmmove3;
- pg_column_compression 
------------------------
- pglz
-(1 row)
-
--- test LIKE INCLUDING COMPRESSION
-CREATE TABLE cmdata2 (LIKE cmdata1 INCLUDING COMPRESSION);
-ERROR:  relation "cmdata1" does not exist
-LINE 1: CREATE TABLE cmdata2 (LIKE cmdata1 INCLUDING COMPRESSION);
-                                   ^
-\d+ cmdata2
-DROP TABLE cmdata2;
-ERROR:  table "cmdata2" does not exist
--- try setting compression for incompressible data type
-CREATE TABLE cmdata2 (f1 int COMPRESSION pglz);
-ERROR:  column data type integer does not support compression
--- update using datum from different table
-CREATE TABLE cmmove2(f1 text COMPRESSION pglz);
-INSERT INTO cmmove2 VALUES (repeat('1234567890', 1004));
-SELECT pg_column_compression(f1) FROM cmmove2;
- pg_column_compression 
------------------------
- pglz
-(1 row)
-
-UPDATE cmmove2 SET f1 = cmdata1.f1 FROM cmdata1;
-ERROR:  relation "cmdata1" does not exist
-LINE 1: UPDATE cmmove2 SET f1 = cmdata1.f1 FROM cmdata1;
-                                                ^
-SELECT pg_column_compression(f1) FROM cmmove2;
- pg_column_compression 
------------------------
- pglz
-(1 row)
-
--- test externally stored compressed data
-CREATE OR REPLACE FUNCTION large_val() RETURNS TEXT LANGUAGE SQL AS
-'select array_agg(fipshash(g::text))::text from generate_series(1, 256) g';
-CREATE TABLE cmdata2 (f1 text COMPRESSION pglz);
-INSERT INTO cmdata2 SELECT large_val() || repeat('a', 4000);
-SELECT pg_column_compression(f1) FROM cmdata2;
- pg_column_compression 
------------------------
- pglz
-(1 row)
-
-INSERT INTO cmdata1 SELECT large_val() || repeat('a', 4000);
-ERROR:  relation "cmdata1" does not exist
-LINE 1: INSERT INTO cmdata1 SELECT large_val() || repeat('a', 4000);
-                    ^
-SELECT pg_column_compression(f1) FROM cmdata1;
-ERROR:  relation "cmdata1" does not exist
-LINE 1: SELECT pg_column_compression(f1) FROM cmdata1;
-                                              ^
-SELECT SUBSTR(f1, 200, 5) FROM cmdata1;
-ERROR:  relation "cmdata1" does not exist
-LINE 1: SELECT SUBSTR(f1, 200, 5) FROM cmdata1;
-                                       ^
-SELECT SUBSTR(f1, 200, 5) FROM cmdata2;
- substr 
---------
- 79026
-(1 row)
-
-DROP TABLE cmdata2;
---test column type update varlena/non-varlena
-CREATE TABLE cmdata2 (f1 int);
-\d+ cmdata2
-                                         Table "public.cmdata2"
- Column |  Type   | Collation | Nullable | Default | Storage | Compression | Stats target | Description 
---------+---------+-----------+----------+---------+---------+-------------+--------------+-------------
- f1     | integer |           |          |         | plain   |             |              | 
-
-ALTER TABLE cmdata2 ALTER COLUMN f1 TYPE varchar;
-\d+ cmdata2
-                                              Table "public.cmdata2"
- Column |       Type        | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
---------+-------------------+-----------+----------+---------+----------+-------------+--------------+-------------
- f1     | character varying |           |          |         | extended |             |              | 
-
-ALTER TABLE cmdata2 ALTER COLUMN f1 TYPE int USING f1::integer;
-\d+ cmdata2
-                                         Table "public.cmdata2"
- Column |  Type   | Collation | Nullable | Default | Storage | Compression | Stats target | Description 
---------+---------+-----------+----------+---------+---------+-------------+--------------+-------------
- f1     | integer |           |          |         | plain   |             |              | 
-
---changing column storage should not impact the compression method
---but the data should not be compressed
-ALTER TABLE cmdata2 ALTER COLUMN f1 TYPE varchar;
-ALTER TABLE cmdata2 ALTER COLUMN f1 SET COMPRESSION pglz;
-\d+ cmdata2
-                                              Table "public.cmdata2"
- Column |       Type        | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
---------+-------------------+-----------+----------+---------+----------+-------------+--------------+-------------
- f1     | character varying |           |          |         | extended | pglz        |              | 
-
-ALTER TABLE cmdata2 ALTER COLUMN f1 SET STORAGE plain;
-\d+ cmdata2
-                                              Table "public.cmdata2"
- Column |       Type        | Collation | Nullable | Default | Storage | Compression | Stats target | Description 
---------+-------------------+-----------+----------+---------+---------+-------------+--------------+-------------
- f1     | character varying |           |          |         | plain   | pglz        |              | 
-
-INSERT INTO cmdata2 VALUES (repeat('123456789', 800));
-SELECT pg_column_compression(f1) FROM cmdata2;
- pg_column_compression 
------------------------
- 
-(1 row)
-
--- test compression with materialized view
-CREATE MATERIALIZED VIEW compressmv(x) AS SELECT * FROM cmdata1;
-ERROR:  relation "cmdata1" does not exist
-LINE 1: ...TE MATERIALIZED VIEW compressmv(x) AS SELECT * FROM cmdata1;
-                                                               ^
-\d+ compressmv
-SELECT pg_column_compression(f1) FROM cmdata1;
-ERROR:  relation "cmdata1" does not exist
-LINE 1: SELECT pg_column_compression(f1) FROM cmdata1;
-                                              ^
-SELECT pg_column_compression(x) FROM compressmv;
-ERROR:  relation "compressmv" does not exist
-LINE 1: SELECT pg_column_compression(x) FROM compressmv;
-                                             ^
--- test compression with partition
-CREATE TABLE cmpart(f1 text COMPRESSION lz4) PARTITION BY HASH(f1);
-ERROR:  compression method lz4 not supported
-DETAIL:  This functionality requires the server to be built with lz4 support.
-CREATE TABLE cmpart1 PARTITION OF cmpart FOR VALUES WITH (MODULUS 2, REMAINDER 0);
-ERROR:  relation "cmpart" does not exist
-CREATE TABLE cmpart2(f1 text COMPRESSION pglz);
-ALTER TABLE cmpart ATTACH PARTITION cmpart2 FOR VALUES WITH (MODULUS 2, REMAINDER 1);
-ERROR:  relation "cmpart" does not exist
-INSERT INTO cmpart VALUES (repeat('123456789', 1004));
-ERROR:  relation "cmpart" does not exist
-LINE 1: INSERT INTO cmpart VALUES (repeat('123456789', 1004));
-                    ^
-INSERT INTO cmpart VALUES (repeat('123456789', 4004));
-ERROR:  relation "cmpart" does not exist
-LINE 1: INSERT INTO cmpart VALUES (repeat('123456789', 4004));
-                    ^
-SELECT pg_column_compression(f1) FROM cmpart1;
-ERROR:  relation "cmpart1" does not exist
-LINE 1: SELECT pg_column_compression(f1) FROM cmpart1;
-                                              ^
-SELECT pg_column_compression(f1) FROM cmpart2;
- pg_column_compression 
------------------------
-(0 rows)
-
--- test compression with inheritance
-CREATE TABLE cminh() INHERITS(cmdata, cmdata1); -- error
-ERROR:  relation "cmdata1" does not exist
-CREATE TABLE cminh(f1 TEXT COMPRESSION lz4) INHERITS(cmdata); -- error
-NOTICE:  merging column "f1" with inherited definition
-ERROR:  column "f1" has a compression method conflict
-DETAIL:  pglz versus lz4
-CREATE TABLE cmdata3(f1 text);
-CREATE TABLE cminh() INHERITS (cmdata, cmdata3);
-NOTICE:  merging multiple inherited definitions of column "f1"
--- test default_toast_compression GUC
-SET default_toast_compression = '';
-ERROR:  invalid value for parameter "default_toast_compression": ""
-HINT:  Available values: pglz.
-SET default_toast_compression = 'I do not exist compression';
-ERROR:  invalid value for parameter "default_toast_compression": "I do not exist compression"
-HINT:  Available values: pglz.
-SET default_toast_compression = 'lz4';
-ERROR:  invalid value for parameter "default_toast_compression": "lz4"
-HINT:  Available values: pglz.
-SET default_toast_compression = 'pglz';
--- test alter compression method
-ALTER TABLE cmdata ALTER COLUMN f1 SET COMPRESSION lz4;
-ERROR:  compression method lz4 not supported
-DETAIL:  This functionality requires the server to be built with lz4 support.
-INSERT INTO cmdata VALUES (repeat('123456789', 4004));
-\d+ cmdata
-                                        Table "public.cmdata"
- Column | Type | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
---------+------+-----------+----------+---------+----------+-------------+--------------+-------------
- f1     | text |           |          |         | extended | pglz        |              | 
-Indexes:
-    "idx" btree (f1)
-Child tables: cminh
-
-SELECT pg_column_compression(f1) FROM cmdata;
- pg_column_compression 
------------------------
- pglz
- pglz
-(2 rows)
-
-ALTER TABLE cmdata2 ALTER COLUMN f1 SET COMPRESSION default;
-\d+ cmdata2
-                                              Table "public.cmdata2"
- Column |       Type        | Collation | Nullable | Default | Storage | Compression | Stats target | Description 
---------+-------------------+-----------+----------+---------+---------+-------------+--------------+-------------
- f1     | character varying |           |          |         | plain   |             |              | 
-
--- test alter compression method for materialized views
-ALTER MATERIALIZED VIEW compressmv ALTER COLUMN x SET COMPRESSION lz4;
-ERROR:  relation "compressmv" does not exist
-\d+ compressmv
--- test alter compression method for partitioned tables
-ALTER TABLE cmpart1 ALTER COLUMN f1 SET COMPRESSION pglz;
-ERROR:  relation "cmpart1" does not exist
-ALTER TABLE cmpart2 ALTER COLUMN f1 SET COMPRESSION lz4;
-ERROR:  compression method lz4 not supported
-DETAIL:  This functionality requires the server to be built with lz4 support.
--- new data should be compressed with the current compression method
-INSERT INTO cmpart VALUES (repeat('123456789', 1004));
-ERROR:  relation "cmpart" does not exist
-LINE 1: INSERT INTO cmpart VALUES (repeat('123456789', 1004));
-                    ^
-INSERT INTO cmpart VALUES (repeat('123456789', 4004));
-ERROR:  relation "cmpart" does not exist
-LINE 1: INSERT INTO cmpart VALUES (repeat('123456789', 4004));
-                    ^
-SELECT pg_column_compression(f1) FROM cmpart1;
-ERROR:  relation "cmpart1" does not exist
-LINE 1: SELECT pg_column_compression(f1) FROM cmpart1;
-                                              ^
-SELECT pg_column_compression(f1) FROM cmpart2;
- pg_column_compression 
------------------------
-(0 rows)
-
--- VACUUM FULL does not recompress
-SELECT pg_column_compression(f1) FROM cmdata;
- pg_column_compression 
------------------------
- pglz
- pglz
-(2 rows)
-
-VACUUM FULL cmdata;
-SELECT pg_column_compression(f1) FROM cmdata;
- pg_column_compression 
------------------------
- pglz
- pglz
-(2 rows)
-
--- test expression index
-DROP TABLE cmdata2;
-CREATE TABLE cmdata2 (f1 TEXT COMPRESSION pglz, f2 TEXT COMPRESSION lz4);
-ERROR:  compression method lz4 not supported
-DETAIL:  This functionality requires the server to be built with lz4 support.
-CREATE UNIQUE INDEX idx1 ON cmdata2 ((f1 || f2));
-ERROR:  relation "cmdata2" does not exist
-INSERT INTO cmdata2 VALUES((SELECT array_agg(fipshash(g::TEXT))::TEXT FROM
-generate_series(1, 50) g), VERSION());
-ERROR:  relation "cmdata2" does not exist
-LINE 1: INSERT INTO cmdata2 VALUES((SELECT array_agg(fipshash(g::TEX...
-                    ^
--- check data is ok
-SELECT length(f1) FROM cmdata;
- length 
---------
-  10000
-  36036
-(2 rows)
-
-SELECT length(f1) FROM cmdata1;
-ERROR:  relation "cmdata1" does not exist
-LINE 1: SELECT length(f1) FROM cmdata1;
-                               ^
-SELECT length(f1) FROM cmmove1;
- length 
---------
-  10000
-(1 row)
-
-SELECT length(f1) FROM cmmove2;
- length 
---------
-  10040
-(1 row)
-
-SELECT length(f1) FROM cmmove3;
- length 
---------
-  10000
-(1 row)
-
-CREATE TABLE badcompresstbl (a text COMPRESSION I_Do_Not_Exist_Compression); -- fails
-ERROR:  invalid compression method "i_do_not_exist_compression"
-CREATE TABLE badcompresstbl (a text);
-ALTER TABLE badcompresstbl ALTER a SET COMPRESSION I_Do_Not_Exist_Compression; -- fails
-ERROR:  invalid compression method "i_do_not_exist_compression"
-DROP TABLE badcompresstbl;
-\set HIDE_TOAST_COMPRESSION true
diff --git a/src/test/regress/expected/compression_lz4.out b/src/test/regress/expected/compression_lz4.out
new file mode 100644
index 0000000000000..068dd7c367446
--- /dev/null
+++ b/src/test/regress/expected/compression_lz4.out
@@ -0,0 +1,249 @@
+-- Tests for TOAST compression with lz4
+SELECT NOT(enumvals @> '{lz4}') AS skip_test FROM pg_settings WHERE
+  name = 'default_toast_compression' \gset
+\if :skip_test
+   \echo '*** skipping TOAST tests with lz4 (not supported) ***'
+   \quit
+\endif
+CREATE SCHEMA lz4;
+SET search_path TO lz4, public;
+\set HIDE_TOAST_COMPRESSION false
+-- Ensure we get stable results regardless of the installation's default.
+-- We rely on this GUC value for a few tests.
+SET default_toast_compression = 'pglz';
+-- test creating table with compression method
+CREATE TABLE cmdata_pglz(f1 text COMPRESSION pglz);
+CREATE INDEX idx ON cmdata_pglz(f1);
+INSERT INTO cmdata_pglz VALUES(repeat('1234567890', 1000));
+\d+ cmdata
+CREATE TABLE cmdata_lz4(f1 TEXT COMPRESSION lz4);
+INSERT INTO cmdata_lz4 VALUES(repeat('1234567890', 1004));
+\d+ cmdata1
+-- verify stored compression method in the data
+SELECT pg_column_compression(f1) FROM cmdata_lz4;
+ pg_column_compression 
+-----------------------
+ lz4
+(1 row)
+
+-- decompress data slice
+SELECT SUBSTR(f1, 200, 5) FROM cmdata_pglz;
+ substr 
+--------
+ 01234
+(1 row)
+
+SELECT SUBSTR(f1, 2000, 50) FROM cmdata_lz4;
+                       substr                       
+----------------------------------------------------
+ 01234567890123456789012345678901234567890123456789
+(1 row)
+
+-- copy with table creation
+SELECT * INTO cmmove1 FROM cmdata_lz4;
+\d+ cmmove1
+                                         Table "lz4.cmmove1"
+ Column | Type | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
+--------+------+-----------+----------+---------+----------+-------------+--------------+-------------
+ f1     | text |           |          |         | extended |             |              | 
+
+SELECT pg_column_compression(f1) FROM cmmove1;
+ pg_column_compression 
+-----------------------
+ lz4
+(1 row)
+
+-- test LIKE INCLUDING COMPRESSION.  The GUC default_toast_compression
+-- has no effect, the compression method from the table being copied.
+CREATE TABLE cmdata2 (LIKE cmdata_lz4 INCLUDING COMPRESSION);
+\d+ cmdata2
+                                         Table "lz4.cmdata2"
+ Column | Type | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
+--------+------+-----------+----------+---------+----------+-------------+--------------+-------------
+ f1     | text |           |          |         | extended | lz4         |              | 
+
+DROP TABLE cmdata2;
+-- copy to existing table
+CREATE TABLE cmmove3(f1 text COMPRESSION pglz);
+INSERT INTO cmmove3 SELECT * FROM cmdata_pglz;
+INSERT INTO cmmove3 SELECT * FROM cmdata_lz4;
+SELECT pg_column_compression(f1) FROM cmmove3;
+ pg_column_compression 
+-----------------------
+ pglz
+ lz4
+(2 rows)
+
+-- update using datum from different table with LZ4 data.
+CREATE TABLE cmmove2(f1 text COMPRESSION pglz);
+INSERT INTO cmmove2 VALUES (repeat('1234567890', 1004));
+SELECT pg_column_compression(f1) FROM cmmove2;
+ pg_column_compression 
+-----------------------
+ pglz
+(1 row)
+
+UPDATE cmmove2 SET f1 = cmdata_lz4.f1 FROM cmdata_lz4;
+SELECT pg_column_compression(f1) FROM cmmove2;
+ pg_column_compression 
+-----------------------
+ lz4
+(1 row)
+
+-- test externally stored compressed data
+CREATE OR REPLACE FUNCTION large_val_lz4() RETURNS TEXT LANGUAGE SQL AS
+'select array_agg(fipshash(g::text))::text from generate_series(1, 256) g';
+CREATE TABLE cmdata2 (f1 text COMPRESSION lz4);
+INSERT INTO cmdata2 SELECT large_val_lz4() || repeat('a', 4000);
+SELECT pg_column_compression(f1) FROM cmdata2;
+ pg_column_compression 
+-----------------------
+ lz4
+(1 row)
+
+SELECT SUBSTR(f1, 200, 5) FROM cmdata2;
+ substr 
+--------
+ 79026
+(1 row)
+
+DROP TABLE cmdata2;
+DROP FUNCTION large_val_lz4;
+-- test compression with materialized view
+CREATE MATERIALIZED VIEW compressmv(x) AS SELECT * FROM cmdata_lz4;
+\d+ compressmv
+                                  Materialized view "lz4.compressmv"
+ Column | Type | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
+--------+------+-----------+----------+---------+----------+-------------+--------------+-------------
+ x      | text |           |          |         | extended |             |              | 
+View definition:
+ SELECT f1 AS x
+   FROM cmdata_lz4;
+
+SELECT pg_column_compression(f1) FROM cmdata_lz4;
+ pg_column_compression 
+-----------------------
+ lz4
+(1 row)
+
+SELECT pg_column_compression(x) FROM compressmv;
+ pg_column_compression 
+-----------------------
+ lz4
+(1 row)
+
+-- test compression with partition
+CREATE TABLE cmpart(f1 text COMPRESSION lz4) PARTITION BY HASH(f1);
+CREATE TABLE cmpart1 PARTITION OF cmpart FOR VALUES WITH (MODULUS 2, REMAINDER 0);
+CREATE TABLE cmpart2(f1 text COMPRESSION pglz);
+ALTER TABLE cmpart ATTACH PARTITION cmpart2 FOR VALUES WITH (MODULUS 2, REMAINDER 1);
+INSERT INTO cmpart VALUES (repeat('123456789', 1004));
+INSERT INTO cmpart VALUES (repeat('123456789', 4004));
+SELECT pg_column_compression(f1) FROM cmpart1;
+ pg_column_compression 
+-----------------------
+ lz4
+(1 row)
+
+SELECT pg_column_compression(f1) FROM cmpart2;
+ pg_column_compression 
+-----------------------
+ pglz
+(1 row)
+
+-- test compression with inheritance
+CREATE TABLE cminh() INHERITS(cmdata_pglz, cmdata_lz4); -- error
+NOTICE:  merging multiple inherited definitions of column "f1"
+ERROR:  column "f1" has a compression method conflict
+DETAIL:  pglz versus lz4
+CREATE TABLE cminh(f1 TEXT COMPRESSION lz4) INHERITS(cmdata_pglz); -- error
+NOTICE:  merging column "f1" with inherited definition
+ERROR:  column "f1" has a compression method conflict
+DETAIL:  pglz versus lz4
+CREATE TABLE cmdata3(f1 text);
+CREATE TABLE cminh() INHERITS (cmdata_pglz, cmdata3);
+NOTICE:  merging multiple inherited definitions of column "f1"
+-- test default_toast_compression GUC
+SET default_toast_compression = 'lz4';
+-- test alter compression method
+ALTER TABLE cmdata_pglz ALTER COLUMN f1 SET COMPRESSION lz4;
+INSERT INTO cmdata_pglz VALUES (repeat('123456789', 4004));
+\d+ cmdata
+SELECT pg_column_compression(f1) FROM cmdata_pglz;
+ pg_column_compression 
+-----------------------
+ pglz
+ lz4
+(2 rows)
+
+ALTER TABLE cmdata_pglz ALTER COLUMN f1 SET COMPRESSION pglz;
+-- test alter compression method for materialized views
+ALTER MATERIALIZED VIEW compressmv ALTER COLUMN x SET COMPRESSION lz4;
+\d+ compressmv
+                                  Materialized view "lz4.compressmv"
+ Column | Type | Collation | Nullable | Default | Storage  | Compression | Stats target | Description 
+--------+------+-----------+----------+---------+----------+-------------+--------------+-------------
+ x      | text |           |          |         | extended | lz4         |              | 
+View definition:
+ SELECT f1 AS x
+   FROM cmdata_lz4;
+
+-- test alter compression method for partitioned tables
+ALTER TABLE cmpart1 ALTER COLUMN f1 SET COMPRESSION pglz;
+ALTER TABLE cmpart2 ALTER COLUMN f1 SET COMPRESSION lz4;
+-- new data should be compressed with the current compression method
+INSERT INTO cmpart VALUES (repeat('123456789', 1004));
+INSERT INTO cmpart VALUES (repeat('123456789', 4004));
+SELECT pg_column_compression(f1) FROM cmpart1;
+ pg_column_compression 
+-----------------------
+ lz4
+ pglz
+(2 rows)
+
+SELECT pg_column_compression(f1) FROM cmpart2;
+ pg_column_compression 
+-----------------------
+ pglz
+ lz4
+(2 rows)
+
+-- test expression index
+CREATE TABLE cmdata2 (f1 TEXT COMPRESSION pglz, f2 TEXT COMPRESSION lz4);
+CREATE UNIQUE INDEX idx1 ON cmdata2 ((f1 || f2));
+INSERT INTO cmdata2 VALUES((SELECT array_agg(fipshash(g::TEXT))::TEXT FROM
+generate_series(1, 50) g), VERSION());
+-- check data is ok
+SELECT length(f1) FROM cmdata_pglz;
+ length 
+--------
+  10000
+  36036
+(2 rows)
+
+SELECT length(f1) FROM cmdata_lz4;
+ length 
+--------
+  10040
+(1 row)
+
+SELECT length(f1) FROM cmmove1;
+ length 
+--------
+  10040
+(1 row)
+
+SELECT length(f1) FROM cmmove2;
+ length 
+--------
+  10040
+(1 row)
+
+SELECT length(f1) FROM cmmove3;
+ length 
+--------
+  10000
+  10040
+(2 rows)
+
+\set HIDE_TOAST_COMPRESSION true
diff --git a/src/test/regress/expected/compression_lz4_1.out b/src/test/regress/expected/compression_lz4_1.out
new file mode 100644
index 0000000000000..198056fa22498
--- /dev/null
+++ b/src/test/regress/expected/compression_lz4_1.out
@@ -0,0 +1,7 @@
+-- Tests for TOAST compression with lz4
+SELECT NOT(enumvals @> '{lz4}') AS skip_test FROM pg_settings WHERE
+  name = 'default_toast_compression' \gset
+\if :skip_test
+   \echo '*** skipping TOAST tests with lz4 (not supported) ***'
+*** skipping TOAST tests with lz4 (not supported) ***
+   \quit
diff --git a/src/test/regress/expected/constraints.out b/src/test/regress/expected/constraints.out
index b5592617d9755..3590d3274f05a 100644
--- a/src/test/regress/expected/constraints.out
+++ b/src/test/regress/expected/constraints.out
@@ -748,6 +748,11 @@ ALTER TABLE unique_tbl ALTER CONSTRAINT unique_tbl_i_key ENFORCED;
 ERROR:  cannot alter enforceability of constraint "unique_tbl_i_key" of relation "unique_tbl"
 ALTER TABLE unique_tbl ALTER CONSTRAINT unique_tbl_i_key NOT ENFORCED;
 ERROR:  cannot alter enforceability of constraint "unique_tbl_i_key" of relation "unique_tbl"
+-- can't make an existing constraint NOT VALID
+ALTER TABLE unique_tbl ALTER CONSTRAINT unique_tbl_i_key NOT VALID;
+ERROR:  constraints cannot be altered to be NOT VALID
+LINE 1: ...ABLE unique_tbl ALTER CONSTRAINT unique_tbl_i_key NOT VALID;
+                                                             ^
 DROP TABLE unique_tbl;
 --
 -- EXCLUDE constraints
@@ -1696,3 +1701,7 @@ DROP TABLE constraint_comments_tbl;
 DROP DOMAIN constraint_comments_dom;
 DROP ROLE regress_constraint_comments;
 DROP ROLE regress_constraint_comments_noaccess;
+-- Leave some constraints for the pg_upgrade test to pick up
+CREATE DOMAIN constraint_comments_dom AS int;
+ALTER DOMAIN constraint_comments_dom ADD CONSTRAINT inv_ck CHECK (value > 0) NOT VALID;
+COMMENT ON CONSTRAINT inv_ck ON DOMAIN constraint_comments_dom IS 'comment on invalid constraint';
diff --git a/src/test/regress/expected/copy.out b/src/test/regress/expected/copy.out
index 8d5a06563c44a..ac66eb55aeed4 100644
--- a/src/test/regress/expected/copy.out
+++ b/src/test/regress/expected/copy.out
@@ -81,6 +81,29 @@ copy copytest4 to stdout (header);
 c1	colname with tab: \t
 1	a
 2	b
+-- test multi-line header line feature
+create temp table copytest5 (c1 int);
+copy copytest5 from stdin (format csv, header 2);
+copy copytest5 to stdout (header);
+c1
+1
+2
+truncate copytest5;
+copy copytest5 from stdin (format csv, header 4);
+select count(*) from copytest5;
+ count 
+-------
+     0
+(1 row)
+
+truncate copytest5;
+copy copytest5 from stdin (format csv, header 5);
+select count(*) from copytest5;
+ count 
+-------
+     0
+(1 row)
+
 -- test copy from with a partitioned table
 create table parted_copytest (
 	a int,
@@ -224,7 +247,7 @@ alter table header_copytest add column c text;
 copy header_copytest to stdout with (header match);
 ERROR:  cannot use "match" with HEADER in COPY TO
 copy header_copytest from stdin with (header wrong_choice);
-ERROR:  header requires a Boolean value or "match"
+ERROR:  header requires a Boolean value, a non-negative integer, or the string "match"
 -- works
 copy header_copytest from stdin with (header match);
 copy header_copytest (c, a, b) from stdin with (header match);
diff --git a/src/test/regress/expected/copy2.out b/src/test/regress/expected/copy2.out
index 64ea33aeae8fd..caa3c44f0d0ca 100644
--- a/src/test/regress/expected/copy2.out
+++ b/src/test/regress/expected/copy2.out
@@ -132,6 +132,12 @@ COPY x from stdin with (reject_limit 1);
 ERROR:  COPY REJECT_LIMIT requires ON_ERROR to be set to IGNORE
 COPY x from stdin with (on_error ignore, reject_limit 0);
 ERROR:  REJECT_LIMIT (0) must be greater than zero
+COPY x from stdin with (header -1);
+ERROR:  a negative integer value cannot be specified for header
+COPY x from stdin with (header 2.5);
+ERROR:  header requires a Boolean value, a non-negative integer, or the string "match"
+COPY x to stdout with (header 2);
+ERROR:  cannot use multi-line header in COPY TO
 -- too many columns in column list: should fail
 COPY x (a, b, c, d, e, d, c) from stdin;
 ERROR:  column "d" specified more than once
diff --git a/src/test/regress/expected/create_index.out b/src/test/regress/expected/create_index.out
index 9ade7b835e69f..98e68e972be05 100644
--- a/src/test/regress/expected/create_index.out
+++ b/src/test/regress/expected/create_index.out
@@ -1624,8 +1624,8 @@ DROP TABLE cwi_test;
 --
 CREATE TABLE syscol_table (a INT);
 -- System columns cannot be indexed
-CREATE INDEX ON syscolcol_table (ctid);
-ERROR:  relation "syscolcol_table" does not exist
+CREATE INDEX ON syscol_table (ctid);
+ERROR:  index creation on system columns is not supported
 -- nor used in expressions
 CREATE INDEX ON syscol_table ((ctid >= '(1000,0)'));
 ERROR:  index creation on system columns is not supported
diff --git a/src/test/regress/expected/domain.out b/src/test/regress/expected/domain.out
index ba6f05eeb7df6..b5ea707df3103 100644
--- a/src/test/regress/expected/domain.out
+++ b/src/test/regress/expected/domain.out
@@ -1019,6 +1019,11 @@ insert into domain_test values (1, 2);
 -- should fail
 alter table domain_test add column c str_domain;
 ERROR:  domain str_domain does not allow null values
+-- disallow duplicated not-null constraints
+create domain int_domain1 as int constraint nn1 not null constraint nn2 not null;
+ERROR:  redundant NOT NULL constraint definition
+LINE 1: ...domain int_domain1 as int constraint nn1 not null constraint...
+                                                             ^
 create domain str_domain2 as text check (value <> 'foo') default 'foo';
 -- should fail
 alter table domain_test add column d str_domain2;
diff --git a/src/test/regress/expected/foreign_key.out b/src/test/regress/expected/foreign_key.out
index 6a8f395934520..dc541d61adfa5 100644
--- a/src/test/regress/expected/foreign_key.out
+++ b/src/test/regress/expected/foreign_key.out
@@ -1359,7 +1359,7 @@ LINE 1: ...e ALTER CONSTRAINT fktable_fk_fkey NOT DEFERRABLE INITIALLY ...
 ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey NO INHERIT;
 ERROR:  constraint "fktable_fk_fkey" of relation "fktable" is not a not-null constraint
 ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey NOT VALID;
-ERROR:  FOREIGN KEY constraints cannot be marked NOT VALID
+ERROR:  constraints cannot be altered to be NOT VALID
 LINE 1: ...ER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey NOT VALID;
                                                              ^
 ALTER TABLE fktable ALTER CONSTRAINT fktable_fk_fkey ENFORCED NOT ENFORCED;
@@ -1750,7 +1750,7 @@ Indexes:
 Referenced by:
     TABLE "fk_partitioned_fk" CONSTRAINT "fk_partitioned_fk_a_b_fkey" FOREIGN KEY (a, b) REFERENCES fk_notpartitioned_pk(a, b)
 
--- Check the exsting FK trigger
+-- Check the existing FK trigger
 SELECT conname, tgrelid::regclass as tgrel, regexp_replace(tgname, '[0-9]+', 'N') as tgname, tgtype
 FROM pg_trigger t JOIN pg_constraint c ON (t.tgconstraint = c.oid)
 WHERE tgrelid IN (SELECT relid FROM pg_partition_tree('fk_partitioned_fk'::regclass)
diff --git a/src/test/regress/expected/generated_stored.out b/src/test/regress/expected/generated_stored.out
index 16de30ab1910b..adac2cedfb2a3 100644
--- a/src/test/regress/expected/generated_stored.out
+++ b/src/test/regress/expected/generated_stored.out
@@ -1313,6 +1313,18 @@ CREATE TABLE gtest31_1 (a int, b text GENERATED ALWAYS AS ('hello') STORED, c te
 CREATE TABLE gtest31_2 (x int, y gtest31_1);
 ALTER TABLE gtest31_1 ALTER COLUMN b TYPE varchar;  -- fails
 ERROR:  cannot alter table "gtest31_1" because column "gtest31_2.y" uses its row type
+-- bug #18970: these cases are unsupported, but make sure they fail cleanly
+ALTER TABLE gtest31_2 ADD CONSTRAINT cc CHECK ((y).b IS NOT NULL);
+ALTER TABLE gtest31_1 ALTER COLUMN b SET EXPRESSION AS ('hello1');
+ERROR:  cannot alter table "gtest31_1" because column "gtest31_2.y" uses its row type
+ALTER TABLE gtest31_2 DROP CONSTRAINT cc;
+CREATE STATISTICS gtest31_2_stat ON ((y).b is not null) FROM gtest31_2;
+ALTER TABLE gtest31_1 ALTER COLUMN b SET EXPRESSION AS ('hello2');
+ERROR:  cannot alter table "gtest31_1" because column "gtest31_2.y" uses its row type
+DROP STATISTICS gtest31_2_stat;
+CREATE INDEX gtest31_2_y_idx ON gtest31_2(((y).b));
+ALTER TABLE gtest31_1 ALTER COLUMN b SET EXPRESSION AS ('hello3');
+ERROR:  cannot alter table "gtest31_1" because column "gtest31_2.y" uses its row type
 DROP TABLE gtest31_1, gtest31_2;
 -- Check it for a partitioned table, too
 CREATE TABLE gtest31_1 (a int, b text GENERATED ALWAYS AS ('hello') STORED, c text) PARTITION BY LIST (a);
diff --git a/src/test/regress/expected/generated_virtual.out b/src/test/regress/expected/generated_virtual.out
index df704b5166fa3..aca6347babe96 100644
--- a/src/test/regress/expected/generated_virtual.out
+++ b/src/test/regress/expected/generated_virtual.out
@@ -1283,6 +1283,15 @@ CREATE TABLE gtest31_1 (a int, b text GENERATED ALWAYS AS ('hello') VIRTUAL, c t
 CREATE TABLE gtest31_2 (x int, y gtest31_1);
 ALTER TABLE gtest31_1 ALTER COLUMN b TYPE varchar;  -- fails
 ERROR:  cannot alter table "gtest31_1" because column "gtest31_2.y" uses its row type
+-- bug #18970
+ALTER TABLE gtest31_2 ADD CONSTRAINT cc CHECK ((y).b IS NOT NULL);
+ALTER TABLE gtest31_1 ALTER COLUMN b SET EXPRESSION AS ('hello1');
+ALTER TABLE gtest31_2 DROP CONSTRAINT cc;
+CREATE STATISTICS gtest31_2_stat ON ((y).b is not null) FROM gtest31_2;
+ALTER TABLE gtest31_1 ALTER COLUMN b SET EXPRESSION AS ('hello2');
+DROP STATISTICS gtest31_2_stat;
+CREATE INDEX gtest31_2_y_idx ON gtest31_2(((y).b));
+ALTER TABLE gtest31_1 ALTER COLUMN b SET EXPRESSION AS ('hello3');
 DROP TABLE gtest31_1, gtest31_2;
 -- Check it for a partitioned table, too
 CREATE TABLE gtest31_1 (a int, b text GENERATED ALWAYS AS ('hello') VIRTUAL, c text) PARTITION BY LIST (a);
@@ -1541,11 +1550,11 @@ where coalesce(t2.b, 1) = 2;
 explain (costs off)
 select t1.a from gtest32 t1 left join gtest32 t2 on t1.a = t2.a
 where coalesce(t2.b, 1) = 2 or t1.a is null;
-                         QUERY PLAN                          
--------------------------------------------------------------
+               QUERY PLAN                
+-----------------------------------------
  Hash Left Join
    Hash Cond: (t1.a = t2.a)
-   Filter: ((COALESCE((t2.a * 2), 1) = 2) OR (t1.a IS NULL))
+   Filter: (COALESCE((t2.a * 2), 1) = 2)
    ->  Seq Scan on gtest32 t1
    ->  Hash
          ->  Seq Scan on gtest32 t2
@@ -1604,4 +1613,26 @@ select * from gtest32 t group by grouping sets (a, b, c, d, e) having c = 20;
 
 -- Ensure that the virtual generated columns in ALTER COLUMN TYPE USING expression are expanded
 alter table gtest32 alter column e type bigint using b;
+-- Ensure that virtual generated column references within SubLinks that should
+-- be transformed into joins can get expanded
+explain (costs off)
+select 1 from gtest32 t1 where exists
+  (select 1 from gtest32 t2 where t1.a > t2.a and t2.b = 2);
+             QUERY PLAN              
+-------------------------------------
+ Nested Loop Semi Join
+   Join Filter: (t1.a > t2.a)
+   ->  Seq Scan on gtest32 t1
+   ->  Materialize
+         ->  Seq Scan on gtest32 t2
+               Filter: ((a * 2) = 2)
+(6 rows)
+
+select 1 from gtest32 t1 where exists
+  (select 1 from gtest32 t2 where t1.a > t2.a and t2.b = 2);
+ ?column? 
+----------
+        1
+(1 row)
+
 drop table gtest32;
diff --git a/src/test/regress/expected/incremental_sort.out b/src/test/regress/expected/incremental_sort.out
index b00219643b9ad..5a1dd9fc02270 100644
--- a/src/test/regress/expected/incremental_sort.out
+++ b/src/test/regress/expected/incremental_sort.out
@@ -1722,3 +1722,43 @@ order by t1.four, t1.two limit 1;
                ->  Seq Scan on tenk1 t2
 (12 rows)
 
+--
+-- Test incremental sort for Append/MergeAppend
+--
+create table prt_tbl (a int, b int) partition by range (a);
+create table prt_tbl_1 partition of prt_tbl for values from (0) to (100);
+create table prt_tbl_2 partition of prt_tbl for values from (100) to (200);
+insert into prt_tbl select i%200, i from generate_series(1,1000)i;
+create index on prt_tbl_1(a);
+create index on prt_tbl_2(a, b);
+analyze prt_tbl;
+set enable_seqscan to off;
+set enable_bitmapscan to off;
+-- Ensure we get an incremental sort for the subpath of Append
+explain (costs off) select * from prt_tbl order by a, b;
+                         QUERY PLAN                         
+------------------------------------------------------------
+ Append
+   ->  Incremental Sort
+         Sort Key: prt_tbl_1.a, prt_tbl_1.b
+         Presorted Key: prt_tbl_1.a
+         ->  Index Scan using prt_tbl_1_a_idx on prt_tbl_1
+   ->  Index Only Scan using prt_tbl_2_a_b_idx on prt_tbl_2
+(6 rows)
+
+-- Ensure we get an incremental sort for the subpath of MergeAppend
+explain (costs off) select * from prt_tbl_1 union all select * from prt_tbl_2 order by a, b;
+                         QUERY PLAN                         
+------------------------------------------------------------
+ Merge Append
+   Sort Key: prt_tbl_1.a, prt_tbl_1.b
+   ->  Incremental Sort
+         Sort Key: prt_tbl_1.a, prt_tbl_1.b
+         Presorted Key: prt_tbl_1.a
+         ->  Index Scan using prt_tbl_1_a_idx on prt_tbl_1
+   ->  Index Only Scan using prt_tbl_2_a_b_idx on prt_tbl_2
+(7 rows)
+
+reset enable_bitmapscan;
+reset enable_seqscan;
+drop table prt_tbl;
diff --git a/src/test/regress/expected/inherit.out b/src/test/regress/expected/inherit.out
index 78dead65325e9..5b5055babdcb0 100644
--- a/src/test/regress/expected/inherit.out
+++ b/src/test/regress/expected/inherit.out
@@ -1898,10 +1898,11 @@ ORDER BY thousand, tenthous;
  Merge Append
    Sort Key: tenk1.thousand, tenk1.tenthous
    ->  Index Only Scan using tenk1_thous_tenthous on tenk1
-   ->  Sort
+   ->  Incremental Sort
          Sort Key: tenk1_1.thousand, tenk1_1.thousand
+         Presorted Key: tenk1_1.thousand
          ->  Index Only Scan using tenk1_thous_tenthous on tenk1 tenk1_1
-(6 rows)
+(7 rows)
 
 explain (costs off)
 SELECT thousand, tenthous, thousand+tenthous AS x FROM tenk1
@@ -1982,10 +1983,11 @@ ORDER BY x, y;
  Merge Append
    Sort Key: a.thousand, a.tenthous
    ->  Index Only Scan using tenk1_thous_tenthous on tenk1 a
-   ->  Sort
+   ->  Incremental Sort
          Sort Key: b.unique2, b.unique2
+         Presorted Key: b.unique2
          ->  Index Only Scan using tenk1_unique2 on tenk1 b
-(6 rows)
+(7 rows)
 
 -- exercise rescan code path via a repeatedly-evaluated subquery
 explain (costs off)
diff --git a/src/test/regress/expected/join.out b/src/test/regress/expected/join.out
index 390aabfb34b9a..4d5d35d07270d 100644
--- a/src/test/regress/expected/join.out
+++ b/src/test/regress/expected/join.out
@@ -3639,8 +3639,8 @@ from nt3 as nt3
     ) as ss2
     on ss2.id = nt3.nt2_id
 where nt3.id = 1 and ss2.b3;
-                  QUERY PLAN                   
------------------------------------------------
+                  QUERY PLAN                  
+----------------------------------------------
  Nested Loop
    ->  Nested Loop
          ->  Index Scan using nt3_pkey on nt3
@@ -3649,7 +3649,7 @@ where nt3.id = 1 and ss2.b3;
                Index Cond: (id = nt3.nt2_id)
    ->  Index Only Scan using nt1_pkey on nt1
          Index Cond: (id = nt2.nt1_id)
-         Filter: (nt2.b1 AND (id IS NOT NULL))
+         Filter: (nt2.b1 AND true)
 (9 rows)
 
 select nt3.id
@@ -5626,14 +5626,14 @@ select * from
   (select 1 as id) as xx
   left join
     (tenk1 as a1 full join (select 1 as id) as yy on (a1.unique1 = yy.id))
-  on (xx.id = coalesce(yy.id));
-              QUERY PLAN               
----------------------------------------
+  on (xx.id = coalesce(yy.id, yy.id));
+                QUERY PLAN                
+------------------------------------------
  Nested Loop Left Join
    ->  Result
    ->  Hash Full Join
          Hash Cond: (a1.unique1 = (1))
-         Filter: (1 = COALESCE((1)))
+         Filter: (1 = COALESCE((1), (1)))
          ->  Seq Scan on tenk1 a1
          ->  Hash
                ->  Result
@@ -5643,7 +5643,7 @@ select * from
   (select 1 as id) as xx
   left join
     (tenk1 as a1 full join (select 1 as id) as yy on (a1.unique1 = yy.id))
-  on (xx.id = coalesce(yy.id));
+  on (xx.id = coalesce(yy.id, yy.id));
  id | unique1 | unique2 | two | four | ten | twenty | hundred | thousand | twothousand | fivethous | tenthous | odd | even | stringu1 | stringu2 | string4 | id 
 ----+---------+---------+-----+------+-----+--------+---------+----------+-------------+-----------+----------+-----+------+----------+----------+---------+----
   1 |       1 |    2838 |   1 |    1 |   1 |      1 |       1 |        1 |           1 |         1 |        1 |   2 |    3 | BAAAAA   | EFEAAA   | OOOOxx  |  1
@@ -8411,20 +8411,20 @@ select * from int4_tbl i left join
 
 explain (verbose, costs off)
 select * from int4_tbl i left join
-  lateral (select coalesce(i) from int2_tbl j where i.f1 = j.f1) k on true;
-             QUERY PLAN              
--------------------------------------
+  lateral (select coalesce(i, i) from int2_tbl j where i.f1 = j.f1) k on true;
+                QUERY PLAN                
+------------------------------------------
  Nested Loop Left Join
-   Output: i.f1, (COALESCE(i.*))
+   Output: i.f1, (COALESCE(i.*, i.*))
    ->  Seq Scan on public.int4_tbl i
          Output: i.f1, i.*
    ->  Seq Scan on public.int2_tbl j
-         Output: j.f1, COALESCE(i.*)
+         Output: j.f1, COALESCE(i.*, i.*)
          Filter: (i.f1 = j.f1)
 (7 rows)
 
 select * from int4_tbl i left join
-  lateral (select coalesce(i) from int2_tbl j where i.f1 = j.f1) k on true;
+  lateral (select coalesce(i, i) from int2_tbl j where i.f1 = j.f1) k on true;
      f1      | coalesce 
 -------------+----------
            0 | (0)
@@ -9593,14 +9593,14 @@ CREATE STATISTICS group_tbl_stat (ndistinct) ON a, b FROM group_tbl;
 ANALYZE group_tbl;
 EXPLAIN (COSTS OFF)
 SELECT 1 FROM group_tbl t1
-    LEFT JOIN (SELECT a c1, COALESCE(a) c2 FROM group_tbl t2) s ON TRUE
+    LEFT JOIN (SELECT a c1, COALESCE(a, a) c2 FROM group_tbl t2) s ON TRUE
 GROUP BY s.c1, s.c2;
-                 QUERY PLAN                 
---------------------------------------------
+                   QUERY PLAN                   
+------------------------------------------------
  Group
-   Group Key: t2.a, (COALESCE(t2.a))
+   Group Key: t2.a, (COALESCE(t2.a, t2.a))
    ->  Sort
-         Sort Key: t2.a, (COALESCE(t2.a))
+         Sort Key: t2.a, (COALESCE(t2.a, t2.a))
          ->  Nested Loop Left Join
                ->  Seq Scan on group_tbl t1
                ->  Seq Scan on group_tbl t2
diff --git a/src/test/regress/expected/memoize.out b/src/test/regress/expected/memoize.out
index 38dfaf021c91d..150dc1b44cf62 100644
--- a/src/test/regress/expected/memoize.out
+++ b/src/test/regress/expected/memoize.out
@@ -25,6 +25,7 @@ begin
         ln := regexp_replace(ln, 'Heap Fetches: \d+', 'Heap Fetches: N');
         ln := regexp_replace(ln, 'loops=\d+', 'loops=N');
         ln := regexp_replace(ln, 'Index Searches: \d+', 'Index Searches: N');
+        ln := regexp_replace(ln, 'Memory: \d+kB', 'Memory: NkB');
         return next ln;
     end loop;
 end;
@@ -500,3 +501,62 @@ RESET max_parallel_workers_per_gather;
 RESET parallel_tuple_cost;
 RESET parallel_setup_cost;
 RESET min_parallel_table_scan_size;
+-- Ensure memoize works for ANTI joins
+CREATE TABLE tab_anti (a int, b boolean);
+INSERT INTO tab_anti SELECT i%3, false FROM generate_series(1,100)i;
+ANALYZE tab_anti;
+-- Ensure we get a Memoize plan for ANTI join
+SELECT explain_memoize('
+SELECT COUNT(*) FROM tab_anti t1 LEFT JOIN
+LATERAL (SELECT DISTINCT ON (a) a, b, t1.a AS x FROM tab_anti t2) t2
+ON t1.a+1 = t2.a
+WHERE t2.a IS NULL;', false);
+                                      explain_memoize                                       
+--------------------------------------------------------------------------------------------
+ Aggregate (actual rows=1.00 loops=N)
+   ->  Nested Loop Anti Join (actual rows=33.00 loops=N)
+         ->  Seq Scan on tab_anti t1 (actual rows=100.00 loops=N)
+         ->  Memoize (actual rows=0.67 loops=N)
+               Cache Key: (t1.a + 1), t1.a
+               Cache Mode: binary
+               Hits: 97  Misses: 3  Evictions: Zero  Overflows: 0  Memory Usage: NkB
+               ->  Subquery Scan on t2 (actual rows=0.67 loops=N)
+                     Filter: ((t1.a + 1) = t2.a)
+                     Rows Removed by Filter: 2
+                     ->  Unique (actual rows=2.67 loops=N)
+                           ->  Sort (actual rows=67.33 loops=N)
+                                 Sort Key: t2_1.a
+                                 Sort Method: quicksort  Memory: NkB
+                                 ->  Seq Scan on tab_anti t2_1 (actual rows=100.00 loops=N)
+(15 rows)
+
+-- And check we get the expected results.
+SELECT COUNT(*) FROM tab_anti t1 LEFT JOIN
+LATERAL (SELECT DISTINCT ON (a) a, b, t1.a AS x FROM tab_anti t2) t2
+ON t1.a+1 = t2.a
+WHERE t2.a IS NULL;
+ count 
+-------
+    33
+(1 row)
+
+-- Ensure we do not add memoize node for SEMI join
+EXPLAIN (COSTS OFF)
+SELECT * FROM tab_anti t1 WHERE t1.a IN
+ (SELECT a FROM tab_anti t2 WHERE t2.b IN
+  (SELECT t1.b FROM tab_anti t3 WHERE t2.a > 1 OFFSET 0));
+                   QUERY PLAN                    
+-------------------------------------------------
+ Nested Loop Semi Join
+   ->  Seq Scan on tab_anti t1
+   ->  Nested Loop Semi Join
+         Join Filter: (t1.a = t2.a)
+         ->  Seq Scan on tab_anti t2
+         ->  Subquery Scan on "ANY_subquery"
+               Filter: (t2.b = "ANY_subquery".b)
+               ->  Result
+                     One-Time Filter: (t2.a > 1)
+                     ->  Seq Scan on tab_anti t3
+(10 rows)
+
+DROP TABLE tab_anti;
diff --git a/src/test/regress/expected/numeric.out b/src/test/regress/expected/numeric.out
index 072d76ce13173..c58e232a2635c 100644
--- a/src/test/regress/expected/numeric.out
+++ b/src/test/regress/expected/numeric.out
@@ -1464,9 +1464,21 @@ ERROR:  count must be greater than zero
 SELECT width_bucket(3.5::float8, 3.0::float8, 3.0::float8, 888);
 ERROR:  lower bound cannot equal upper bound
 SELECT width_bucket('NaN', 3.0, 4.0, 888);
-ERROR:  operand, lower bound, and upper bound cannot be NaN
+ width_bucket 
+--------------
+          889
+(1 row)
+
+SELECT width_bucket('NaN'::float8, 3.0::float8, 4.0::float8, 888);
+ width_bucket 
+--------------
+          889
+(1 row)
+
+SELECT width_bucket(0, 'NaN', 4.0, 888);
+ERROR:  lower and upper bounds cannot be NaN
 SELECT width_bucket(0::float8, 'NaN', 4.0::float8, 888);
-ERROR:  operand, lower bound, and upper bound cannot be NaN
+ERROR:  lower and upper bounds cannot be NaN
 SELECT width_bucket(2.0, 3.0, '-inf', 888);
 ERROR:  lower and upper bounds must be finite
 SELECT width_bucket(0::float8, '-inf', 4.0::float8, 888);
@@ -3860,15 +3872,15 @@ ERROR:  factorial of a negative number is undefined
 -- Tests for pg_lsn()
 --
 SELECT pg_lsn(23783416::numeric);
-  pg_lsn   
------------
- 0/16AE7F8
+   pg_lsn   
+------------
+ 0/016AE7F8
 (1 row)
 
 SELECT pg_lsn(0::numeric);
- pg_lsn 
---------
- 0/0
+   pg_lsn   
+------------
+ 0/00000000
 (1 row)
 
 SELECT pg_lsn(18446744073709551615::numeric);
diff --git a/src/test/regress/expected/pg_lsn.out b/src/test/regress/expected/pg_lsn.out
index b27eec7c01503..8ab59b2e44593 100644
--- a/src/test/regress/expected/pg_lsn.out
+++ b/src/test/regress/expected/pg_lsn.out
@@ -41,9 +41,9 @@ SELECT * FROM pg_input_error_info('16AE7F7', 'pg_lsn');
 
 -- Min/Max aggregation
 SELECT MIN(f1), MAX(f1) FROM PG_LSN_TBL;
- min |        max        
------+-------------------
- 0/0 | FFFFFFFF/FFFFFFFF
+    min     |        max        
+------------+-------------------
+ 0/00000000 | FFFFFFFF/FFFFFFFF
 (1 row)
 
 DROP TABLE PG_LSN_TBL;
@@ -85,21 +85,21 @@ SELECT '0/16AE7F8'::pg_lsn - '0/16AE7F7'::pg_lsn;
 (1 row)
 
 SELECT '0/16AE7F7'::pg_lsn + 16::numeric;
- ?column?  
------------
- 0/16AE807
+  ?column?  
+------------
+ 0/016AE807
 (1 row)
 
 SELECT 16::numeric + '0/16AE7F7'::pg_lsn;
- ?column?  
------------
- 0/16AE807
+  ?column?  
+------------
+ 0/016AE807
 (1 row)
 
 SELECT '0/16AE7F7'::pg_lsn - 16::numeric;
- ?column?  
------------
- 0/16AE7E7
+  ?column?  
+------------
+ 0/016AE7E7
 (1 row)
 
 SELECT 'FFFFFFFF/FFFFFFFE'::pg_lsn + 1::numeric;
@@ -111,9 +111,9 @@ SELECT 'FFFFFFFF/FFFFFFFE'::pg_lsn + 1::numeric;
 SELECT 'FFFFFFFF/FFFFFFFE'::pg_lsn + 2::numeric; -- out of range error
 ERROR:  pg_lsn out of range
 SELECT '0/1'::pg_lsn - 1::numeric;
- ?column? 
-----------
- 0/0
+  ?column?  
+------------
+ 0/00000000
 (1 row)
 
 SELECT '0/1'::pg_lsn - 2::numeric; -- out of range error
@@ -125,9 +125,9 @@ SELECT '0/0'::pg_lsn + ('FFFFFFFF/FFFFFFFF'::pg_lsn - '0/0'::pg_lsn);
 (1 row)
 
 SELECT 'FFFFFFFF/FFFFFFFF'::pg_lsn - ('FFFFFFFF/FFFFFFFF'::pg_lsn - '0/0'::pg_lsn);
- ?column? 
-----------
- 0/0
+  ?column?  
+------------
+ 0/00000000
 (1 row)
 
 SELECT '0/16AE7F7'::pg_lsn + 'NaN'::numeric;
@@ -164,107 +164,107 @@ SELECT DISTINCT (i || '/' || j)::pg_lsn f
        generate_series(1, 5) k
   WHERE i <= 10 AND j > 0 AND j <= 10
   ORDER BY f;
-   f   
--------
- 1/1
- 1/2
- 1/3
- 1/4
- 1/5
- 1/6
- 1/7
- 1/8
- 1/9
- 1/10
- 2/1
- 2/2
- 2/3
- 2/4
- 2/5
- 2/6
- 2/7
- 2/8
- 2/9
- 2/10
- 3/1
- 3/2
- 3/3
- 3/4
- 3/5
- 3/6
- 3/7
- 3/8
- 3/9
- 3/10
- 4/1
- 4/2
- 4/3
- 4/4
- 4/5
- 4/6
- 4/7
- 4/8
- 4/9
- 4/10
- 5/1
- 5/2
- 5/3
- 5/4
- 5/5
- 5/6
- 5/7
- 5/8
- 5/9
- 5/10
- 6/1
- 6/2
- 6/3
- 6/4
- 6/5
- 6/6
- 6/7
- 6/8
- 6/9
- 6/10
- 7/1
- 7/2
- 7/3
- 7/4
- 7/5
- 7/6
- 7/7
- 7/8
- 7/9
- 7/10
- 8/1
- 8/2
- 8/3
- 8/4
- 8/5
- 8/6
- 8/7
- 8/8
- 8/9
- 8/10
- 9/1
- 9/2
- 9/3
- 9/4
- 9/5
- 9/6
- 9/7
- 9/8
- 9/9
- 9/10
- 10/1
- 10/2
- 10/3
- 10/4
- 10/5
- 10/6
- 10/7
- 10/8
- 10/9
- 10/10
+      f      
+-------------
+ 1/00000001
+ 1/00000002
+ 1/00000003
+ 1/00000004
+ 1/00000005
+ 1/00000006
+ 1/00000007
+ 1/00000008
+ 1/00000009
+ 1/00000010
+ 2/00000001
+ 2/00000002
+ 2/00000003
+ 2/00000004
+ 2/00000005
+ 2/00000006
+ 2/00000007
+ 2/00000008
+ 2/00000009
+ 2/00000010
+ 3/00000001
+ 3/00000002
+ 3/00000003
+ 3/00000004
+ 3/00000005
+ 3/00000006
+ 3/00000007
+ 3/00000008
+ 3/00000009
+ 3/00000010
+ 4/00000001
+ 4/00000002
+ 4/00000003
+ 4/00000004
+ 4/00000005
+ 4/00000006
+ 4/00000007
+ 4/00000008
+ 4/00000009
+ 4/00000010
+ 5/00000001
+ 5/00000002
+ 5/00000003
+ 5/00000004
+ 5/00000005
+ 5/00000006
+ 5/00000007
+ 5/00000008
+ 5/00000009
+ 5/00000010
+ 6/00000001
+ 6/00000002
+ 6/00000003
+ 6/00000004
+ 6/00000005
+ 6/00000006
+ 6/00000007
+ 6/00000008
+ 6/00000009
+ 6/00000010
+ 7/00000001
+ 7/00000002
+ 7/00000003
+ 7/00000004
+ 7/00000005
+ 7/00000006
+ 7/00000007
+ 7/00000008
+ 7/00000009
+ 7/00000010
+ 8/00000001
+ 8/00000002
+ 8/00000003
+ 8/00000004
+ 8/00000005
+ 8/00000006
+ 8/00000007
+ 8/00000008
+ 8/00000009
+ 8/00000010
+ 9/00000001
+ 9/00000002
+ 9/00000003
+ 9/00000004
+ 9/00000005
+ 9/00000006
+ 9/00000007
+ 9/00000008
+ 9/00000009
+ 9/00000010
+ 10/00000001
+ 10/00000002
+ 10/00000003
+ 10/00000004
+ 10/00000005
+ 10/00000006
+ 10/00000007
+ 10/00000008
+ 10/00000009
+ 10/00000010
 (100 rows)
 
diff --git a/src/test/regress/expected/predicate.out b/src/test/regress/expected/predicate.out
index b79037748b7e6..59bfe33bb1ce1 100644
--- a/src/test/regress/expected/predicate.out
+++ b/src/test/regress/expected/predicate.out
@@ -84,10 +84,10 @@ SELECT * FROM pred_tab t WHERE t.a IS NULL OR t.c IS NULL;
 -- are provably false
 EXPLAIN (COSTS OFF)
 SELECT * FROM pred_tab t WHERE t.b IS NULL OR t.c IS NULL;
-               QUERY PLAN               
-----------------------------------------
+       QUERY PLAN       
+------------------------
  Seq Scan on pred_tab t
-   Filter: ((b IS NULL) OR (c IS NULL))
+   Filter: (b IS NULL)
 (2 rows)
 
 --
@@ -231,6 +231,54 @@ SELECT * FROM pred_tab t1
          ->  Seq Scan on pred_tab t3
 (9 rows)
 
+--
+-- Tests for NullTest reduction in EXISTS sublink
+--
+-- Ensure the IS_NOT_NULL qual is ignored
+EXPLAIN (COSTS OFF)
+SELECT * FROM pred_tab t1
+    LEFT JOIN pred_tab t2 ON EXISTS
+        (SELECT 1 FROM pred_tab t3, pred_tab t4, pred_tab t5, pred_tab t6
+         WHERE t1.a = t3.a AND t6.a IS NOT NULL);
+                       QUERY PLAN                        
+---------------------------------------------------------
+ Nested Loop Left Join
+   Join Filter: EXISTS(SubPlan 1)
+   ->  Seq Scan on pred_tab t1
+   ->  Materialize
+         ->  Seq Scan on pred_tab t2
+   SubPlan 1
+     ->  Nested Loop
+           ->  Nested Loop
+                 ->  Nested Loop
+                       ->  Seq Scan on pred_tab t4
+                       ->  Materialize
+                             ->  Seq Scan on pred_tab t3
+                                   Filter: (t1.a = a)
+                 ->  Materialize
+                       ->  Seq Scan on pred_tab t5
+           ->  Materialize
+                 ->  Seq Scan on pred_tab t6
+(17 rows)
+
+-- Ensure the IS_NULL qual is reduced to constant-FALSE
+EXPLAIN (COSTS OFF)
+SELECT * FROM pred_tab t1
+    LEFT JOIN pred_tab t2 ON EXISTS
+        (SELECT 1 FROM pred_tab t3, pred_tab t4, pred_tab t5, pred_tab t6
+         WHERE t1.a = t3.a AND t6.a IS NULL);
+             QUERY PLAN              
+-------------------------------------
+ Nested Loop Left Join
+   Join Filter: (InitPlan 1).col1
+   InitPlan 1
+     ->  Result
+           One-Time Filter: false
+   ->  Seq Scan on pred_tab t1
+   ->  Materialize
+         ->  Seq Scan on pred_tab t2
+(8 rows)
+
 DROP TABLE pred_tab;
 -- Validate we handle IS NULL and IS NOT NULL quals correctly with inheritance
 -- parents.
diff --git a/src/test/regress/expected/privileges.out b/src/test/regress/expected/privileges.out
index c25062c288f32..602a6b255bc08 100644
--- a/src/test/regress/expected/privileges.out
+++ b/src/test/regress/expected/privileges.out
@@ -2568,6 +2568,26 @@ SELECT makeaclitem('regress_priv_user1'::regrole, 'regress_priv_user2'::regrole,
 SELECT makeaclitem('regress_priv_user1'::regrole, 'regress_priv_user2'::regrole,
 	'SELECT, fake_privilege', FALSE);  -- error
 ERROR:  unrecognized privilege type: "fake_privilege"
+-- Test quoting and dequoting of user names in ACLs
+CREATE ROLE "regress_""quoted";
+SELECT makeaclitem('regress_"quoted'::regrole, 'regress_"quoted'::regrole,
+                   'SELECT', TRUE);
+               makeaclitem                
+------------------------------------------
+ "regress_""quoted"=r*/"regress_""quoted"
+(1 row)
+
+SELECT '"regress_""quoted"=r*/"regress_""quoted"'::aclitem;
+                 aclitem                  
+------------------------------------------
+ "regress_""quoted"=r*/"regress_""quoted"
+(1 row)
+
+SELECT '""=r*/""'::aclitem;  -- used to be misparsed as """"
+ERROR:  a name must follow the "/" sign
+LINE 1: SELECT '""=r*/""'::aclitem;
+               ^
+DROP ROLE "regress_""quoted";
 -- Test non-throwing aclitem I/O
 SELECT pg_input_is_valid('regress_priv_user1=r/regress_priv_user2', 'aclitem');
  pg_input_is_valid 
@@ -3220,7 +3240,8 @@ REVOKE MAINTAIN ON lock_table FROM regress_locktable_user;
 DROP TABLE lock_table;
 DROP USER regress_locktable_user;
 -- test to check privileges of system views pg_shmem_allocations,
--- pg_shmem_allocations_numa and pg_backend_memory_contexts.
+-- pg_shmem_allocations_numa, pg_dsm_registry_allocations, and
+-- pg_backend_memory_contexts.
 -- switch to superuser
 \c -
 CREATE ROLE regress_readallstats;
@@ -3248,6 +3269,12 @@ SELECT has_table_privilege('regress_readallstats','pg_shmem_allocations_numa','S
  f
 (1 row)
 
+SELECT has_table_privilege('regress_readallstats','pg_dsm_registry_allocations','SELECT'); -- no
+ has_table_privilege 
+---------------------
+ f
+(1 row)
+
 GRANT pg_read_all_stats TO regress_readallstats;
 SELECT has_table_privilege('regress_readallstats','pg_aios','SELECT'); -- yes
  has_table_privilege 
@@ -3273,6 +3300,12 @@ SELECT has_table_privilege('regress_readallstats','pg_shmem_allocations_numa','S
  t
 (1 row)
 
+SELECT has_table_privilege('regress_readallstats','pg_dsm_registry_allocations','SELECT'); -- yes
+ has_table_privilege 
+---------------------
+ t
+(1 row)
+
 -- run query to ensure that functions within views can be executed
 SET ROLE regress_readallstats;
 SELECT COUNT(*) >= 0 AS ok FROM pg_aios;
diff --git a/src/test/regress/expected/publication.out b/src/test/regress/expected/publication.out
index 3a2eacd793f70..53268059142ee 100644
--- a/src/test/regress/expected/publication.out
+++ b/src/test/regress/expected/publication.out
@@ -36,6 +36,9 @@ LINE 1: ...pub_xxx WITH (publish_generated_columns = stored, publish_ge...
 CREATE PUBLICATION testpub_xxx WITH (publish_generated_columns = foo);
 ERROR:  invalid value for publication parameter "publish_generated_columns": "foo"
 DETAIL:  Valid values are "none" and "stored".
+CREATE PUBLICATION testpub_xxx WITH (publish_generated_columns);
+ERROR:  invalid value for publication parameter "publish_generated_columns": ""
+DETAIL:  Valid values are "none" and "stored".
 \dRp
                                                         List of publications
         Name        |          Owner           | All tables | Inserts | Updates | Deletes | Truncates | Generated columns | Via root 
@@ -1844,8 +1847,7 @@ DROP SCHEMA sch1 cascade;
 DROP SCHEMA sch2 cascade;
 -- ======================================================
 -- Test the 'publish_generated_columns' parameter with the following values:
--- 'stored', 'none', and the default (no value specified), which defaults to
--- 'stored'.
+-- 'stored', 'none'.
 SET client_min_messages = 'ERROR';
 CREATE PUBLICATION pub1 FOR ALL TABLES WITH (publish_generated_columns = stored);
 \dRp+ pub1
@@ -1863,17 +1865,8 @@ CREATE PUBLICATION pub2 FOR ALL TABLES WITH (publish_generated_columns = none);
  regress_publication_user | t          | t       | t       | t       | t         | none              | f
 (1 row)
 
-CREATE PUBLICATION pub3 FOR ALL TABLES WITH (publish_generated_columns);
-\dRp+ pub3
-                                                Publication pub3
-          Owner           | All tables | Inserts | Updates | Deletes | Truncates | Generated columns | Via root 
---------------------------+------------+---------+---------+---------+-----------+-------------------+----------
- regress_publication_user | t          | t       | t       | t       | t         | stored            | f
-(1 row)
-
 DROP PUBLICATION pub1;
 DROP PUBLICATION pub2;
-DROP PUBLICATION pub3;
 -- Test the 'publish_generated_columns' parameter as 'none' and 'stored' for
 -- different scenarios with/without generated columns in column lists.
 CREATE TABLE gencols (a int, gen1 int GENERATED ALWAYS AS (a * 2) STORED);
@@ -1934,3 +1927,24 @@ RESET client_min_messages;
 RESET SESSION AUTHORIZATION;
 DROP ROLE regress_publication_user, regress_publication_user2;
 DROP ROLE regress_publication_user_dummy;
+-- stage objects for pg_dump tests
+CREATE SCHEMA pubme CREATE TABLE t0 (c int, d int) CREATE TABLE t1 (c int);
+CREATE SCHEMA pubme2 CREATE TABLE t0 (c int, d int);
+SET client_min_messages = 'ERROR';
+CREATE PUBLICATION dump_pub_qual_1ct FOR
+  TABLE ONLY pubme.t0 (c, d) WHERE (c > 0);
+CREATE PUBLICATION dump_pub_qual_2ct FOR
+  TABLE ONLY pubme.t0 (c) WHERE (c > 0),
+  TABLE ONLY pubme.t1 (c);
+CREATE PUBLICATION dump_pub_nsp_1ct FOR
+  TABLES IN SCHEMA pubme;
+CREATE PUBLICATION dump_pub_nsp_2ct FOR
+  TABLES IN SCHEMA pubme,
+  TABLES IN SCHEMA pubme2;
+CREATE PUBLICATION dump_pub_all FOR
+  TABLE ONLY pubme.t0,
+  TABLE ONLY pubme.t1 WHERE (c < 0),
+  TABLES IN SCHEMA pubme,
+  TABLES IN SCHEMA pubme2
+  WITH (publish_via_partition_root = true);
+RESET client_min_messages;
diff --git a/src/test/regress/expected/regproc.out b/src/test/regress/expected/regproc.out
index 97b917502cabb..84c84aef4207f 100644
--- a/src/test/regress/expected/regproc.out
+++ b/src/test/regress/expected/regproc.out
@@ -192,6 +192,18 @@ SELECT regnamespace('"pg_catalog"');
  pg_catalog
 (1 row)
 
+SELECT regdatabase('template1');
+ regdatabase 
+-------------
+ template1
+(1 row)
+
+SELECT regdatabase('"template1"');
+ regdatabase 
+-------------
+ template1
+(1 row)
+
 SELECT to_regrole('regress_regrole_test');
       to_regrole      
 ----------------------
@@ -216,6 +228,132 @@ SELECT to_regnamespace('"pg_catalog"');
  pg_catalog
 (1 row)
 
+SELECT to_regdatabase('template1');
+ to_regdatabase 
+----------------
+ template1
+(1 row)
+
+SELECT to_regdatabase('"template1"');
+ to_regdatabase 
+----------------
+ template1
+(1 row)
+
+-- special "single dash" case
+SELECT regproc('-')::oid;
+ regproc 
+---------
+       0
+(1 row)
+
+SELECT regprocedure('-')::oid;
+ regprocedure 
+--------------
+            0
+(1 row)
+
+SELECT regclass('-')::oid;
+ regclass 
+----------
+        0
+(1 row)
+
+SELECT regcollation('-')::oid;
+ regcollation 
+--------------
+            0
+(1 row)
+
+SELECT regtype('-')::oid;
+ regtype 
+---------
+       0
+(1 row)
+
+SELECT regconfig('-')::oid;
+ regconfig 
+-----------
+         0
+(1 row)
+
+SELECT regdictionary('-')::oid;
+ regdictionary 
+---------------
+             0
+(1 row)
+
+SELECT regrole('-')::oid;
+ regrole 
+---------
+       0
+(1 row)
+
+SELECT regnamespace('-')::oid;
+ regnamespace 
+--------------
+            0
+(1 row)
+
+SELECT regdatabase('-')::oid;
+ regdatabase 
+-------------
+           0
+(1 row)
+
+SELECT to_regproc('-')::oid;
+ to_regproc 
+------------
+          0
+(1 row)
+
+SELECT to_regprocedure('-')::oid;
+ to_regprocedure 
+-----------------
+               0
+(1 row)
+
+SELECT to_regclass('-')::oid;
+ to_regclass 
+-------------
+           0
+(1 row)
+
+SELECT to_regcollation('-')::oid;
+ to_regcollation 
+-----------------
+               0
+(1 row)
+
+SELECT to_regtype('-')::oid;
+ to_regtype 
+------------
+          0
+(1 row)
+
+SELECT to_regrole('-')::oid;
+ to_regrole 
+------------
+          0
+(1 row)
+
+SELECT to_regnamespace('-')::oid;
+ to_regnamespace 
+-----------------
+               0
+(1 row)
+
+SELECT to_regdatabase('-')::oid;
+ to_regdatabase 
+----------------
+              0
+(1 row)
+
+-- constant cannot be used here
+CREATE TABLE regrole_test (rolid OID DEFAULT 'regress_regrole_test'::regrole);
+ERROR:  constant of the type regrole cannot be used here
+CREATE TABLE regdatabase_test (datid OID DEFAULT 'template1'::regdatabase);
+ERROR:  constant of the type regdatabase cannot be used here
 /* If objects don't exist, raise errors. */
 DROP ROLE regress_regrole_test;
 -- without schemaname
@@ -305,6 +443,18 @@ SELECT regnamespace('foo.bar');
 ERROR:  invalid name syntax
 LINE 1: SELECT regnamespace('foo.bar');
                             ^
+SELECT regdatabase('Nonexistent');
+ERROR:  database "nonexistent" does not exist
+LINE 1: SELECT regdatabase('Nonexistent');
+                           ^
+SELECT regdatabase('"Nonexistent"');
+ERROR:  database "Nonexistent" does not exist
+LINE 1: SELECT regdatabase('"Nonexistent"');
+                           ^
+SELECT regdatabase('foo.bar');
+ERROR:  invalid name syntax
+LINE 1: SELECT regdatabase('foo.bar');
+                           ^
 /* If objects don't exist, return NULL with no error. */
 -- without schemaname
 SELECT to_regoper('||//');
@@ -447,6 +597,24 @@ SELECT to_regnamespace('foo.bar');
  
 (1 row)
 
+SELECT to_regdatabase('Nonexistent');
+ to_regdatabase 
+----------------
+ 
+(1 row)
+
+SELECT to_regdatabase('"Nonexistent"');
+ to_regdatabase 
+----------------
+ 
+(1 row)
+
+SELECT to_regdatabase('foo.bar');
+ to_regdatabase 
+----------------
+ 
+(1 row)
+
 -- Test to_regtypemod
 SELECT to_regtypemod('text');
  to_regtypemod 
@@ -569,6 +737,12 @@ SELECT * FROM pg_input_error_info('no_such_type', 'regtype');
  type "no_such_type" does not exist |        |      | 42704
 (1 row)
 
+SELECT * FROM pg_input_error_info('Nonexistent', 'regdatabase');
+                message                | detail | hint | sql_error_code 
+---------------------------------------+--------+------+----------------
+ database "nonexistent" does not exist |        |      | 42704
+(1 row)
+
 -- Some cases that should be soft errors, but are not yet
 SELECT * FROM pg_input_error_info('incorrect type name syntax', 'regtype');
 ERROR:  syntax error at or near "type"
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 6cf828ca8d0dc..35e8aad7701be 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1340,6 +1340,10 @@ pg_cursors| SELECT name,
     is_scrollable,
     creation_time
    FROM pg_cursor() c(name, statement, is_holdable, is_binary, is_scrollable, creation_time);
+pg_dsm_registry_allocations| SELECT name,
+    type,
+    size
+   FROM pg_get_dsm_registry_allocations() pg_get_dsm_registry_allocations(name, type, size);
 pg_file_settings| SELECT sourcefile,
     sourceline,
     seqno,
@@ -1973,7 +1977,12 @@ pg_stat_progress_basebackup| SELECT pid,
         END AS backup_total,
     param3 AS backup_streamed,
     param4 AS tablespaces_total,
-    param5 AS tablespaces_streamed
+    param5 AS tablespaces_streamed,
+        CASE param6
+            WHEN 1 THEN 'full'::text
+            WHEN 2 THEN 'incremental'::text
+            ELSE NULL::text
+        END AS backup_type
    FROM pg_stat_get_progress_info('BASEBACKUP'::text) s(pid, datid, relid, param1, param2, param3, param4, param5, param6, param7, param8, param9, param10, param11, param12, param13, param14, param15, param16, param17, param18, param19, param20);
 pg_stat_progress_cluster| SELECT s.pid,
     s.datid,
@@ -2175,13 +2184,14 @@ pg_stat_subscription_stats| SELECT ss.subid,
     ss.confl_insert_exists,
     ss.confl_update_origin_differs,
     ss.confl_update_exists,
+    ss.confl_update_deleted,
     ss.confl_update_missing,
     ss.confl_delete_origin_differs,
     ss.confl_delete_missing,
     ss.confl_multiple_unique_conflicts,
     ss.stats_reset
    FROM pg_subscription s,
-    LATERAL pg_stat_get_subscription_stats(s.oid) ss(subid, apply_error_count, sync_error_count, confl_insert_exists, confl_update_origin_differs, confl_update_exists, confl_update_missing, confl_delete_origin_differs, confl_delete_missing, confl_multiple_unique_conflicts, stats_reset);
+    LATERAL pg_stat_get_subscription_stats(s.oid) ss(subid, apply_error_count, sync_error_count, confl_insert_exists, confl_update_origin_differs, confl_update_exists, confl_update_deleted, confl_update_missing, confl_delete_origin_differs, confl_delete_missing, confl_multiple_unique_conflicts, stats_reset);
 pg_stat_sys_indexes| SELECT relid,
     indexrelid,
     schemaname,
diff --git a/src/test/regress/expected/stats.out b/src/test/regress/expected/stats.out
index 776f1ad0e5347..605f50703769a 100644
--- a/src/test/regress/expected/stats.out
+++ b/src/test/regress/expected/stats.out
@@ -926,8 +926,19 @@ DROP TABLE test_stats_temp;
 -- Checkpoint twice: The checkpointer reports stats after reporting completion
 -- of the checkpoint. But after a second checkpoint we'll see at least the
 -- results of the first.
-CHECKPOINT;
-CHECKPOINT;
+--
+-- While at it, test checkpoint options.  Note that we don't test MODE SPREAD
+-- because it would prolong the test.
+CHECKPOINT (WRONG);
+ERROR:  unrecognized CHECKPOINT option "wrong"
+LINE 1: CHECKPOINT (WRONG);
+                    ^
+CHECKPOINT (MODE WRONG);
+ERROR:  unrecognized MODE option "wrong"
+LINE 1: CHECKPOINT (MODE WRONG);
+                    ^
+CHECKPOINT (MODE FAST, FLUSH_UNLOGGED FALSE);
+CHECKPOINT (FLUSH_UNLOGGED);
 SELECT num_requested > :rqst_ckpts_before FROM pg_stat_checkpointer;
  ?column? 
 ----------
diff --git a/src/test/regress/expected/strings.out b/src/test/regress/expected/strings.out
index 788844abd20e3..1bfd33de3f3c3 100644
--- a/src/test/regress/expected/strings.out
+++ b/src/test/regress/expected/strings.out
@@ -236,6 +236,12 @@ SELECT E'De\\678dBeEf'::bytea;
 ERROR:  invalid input syntax for type bytea
 LINE 1: SELECT E'De\\678dBeEf'::bytea;
                ^
+SELECT E'DeAd\\\\BeEf'::bytea;
+        bytea         
+----------------------
+ \x446541645c42654566
+(1 row)
+
 SELECT reverse(''::bytea);
  reverse 
 ---------
@@ -291,6 +297,12 @@ SELECT E'De\\123dBeEf'::bytea;
  DeSdBeEf
 (1 row)
 
+SELECT E'DeAd\\\\BeEf'::bytea;
+   bytea    
+------------
+ DeAd\\BeEf
+(1 row)
+
 -- Test non-error-throwing API too
 SELECT pg_input_is_valid(E'\\xDeAdBeE', 'bytea');
  pg_input_is_valid 
diff --git a/src/test/regress/expected/subscription.out b/src/test/regress/expected/subscription.out
index 1443e1d929296..a98c97f761689 100644
--- a/src/test/regress/expected/subscription.out
+++ b/src/test/regress/expected/subscription.out
@@ -116,18 +116,18 @@ CREATE SUBSCRIPTION regress_testsub4 CONNECTION 'dbname=regress_doesnotexist' PU
 WARNING:  subscription was created, but is not connected
 HINT:  To initiate replication, you must manually create the replication slot, enable the subscription, and refresh the subscription.
 \dRs+ regress_testsub4
-                                                                                                                 List of subscriptions
-       Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |          Conninfo           | Skip LSN 
-------------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+-----------------------------+----------
- regress_testsub4 | regress_subscription_user | f       | {testpub}   | f      | parallel  | d                | f                | none   | t                 | f             | f        | off                | dbname=regress_doesnotexist | 0/0
+                                                                                                                            List of subscriptions
+       Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |          Conninfo           |  Skip LSN  
+------------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+-----------------------------+------------
+ regress_testsub4 | regress_subscription_user | f       | {testpub}   | f      | parallel  | d                | f                | none   | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist | 0/00000000
 (1 row)
 
 ALTER SUBSCRIPTION regress_testsub4 SET (origin = any);
 \dRs+ regress_testsub4
-                                                                                                                 List of subscriptions
-       Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |          Conninfo           | Skip LSN 
-------------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+-----------------------------+----------
- regress_testsub4 | regress_subscription_user | f       | {testpub}   | f      | parallel  | d                | f                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist | 0/0
+                                                                                                                            List of subscriptions
+       Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |          Conninfo           |  Skip LSN  
+------------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+-----------------------------+------------
+ regress_testsub4 | regress_subscription_user | f       | {testpub}   | f      | parallel  | d                | f                | any    | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist | 0/00000000
 (1 row)
 
 DROP SUBSCRIPTION regress_testsub3;
@@ -145,10 +145,10 @@ ALTER SUBSCRIPTION regress_testsub CONNECTION 'foobar';
 ERROR:  invalid connection string syntax: missing "=" after "foobar" in connection info string
 
 \dRs+
-                                                                                                                List of subscriptions
-      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |          Conninfo           | Skip LSN 
------------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+-----------------------------+----------
- regress_testsub | regress_subscription_user | f       | {testpub}   | f      | parallel  | d                | f                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist | 0/0
+                                                                                                                            List of subscriptions
+      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |          Conninfo           |  Skip LSN  
+-----------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+-----------------------------+------------
+ regress_testsub | regress_subscription_user | f       | {testpub}   | f      | parallel  | d                | f                | any    | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist | 0/00000000
 (1 row)
 
 ALTER SUBSCRIPTION regress_testsub SET PUBLICATION testpub2, testpub3 WITH (refresh = false);
@@ -157,10 +157,10 @@ ALTER SUBSCRIPTION regress_testsub SET (slot_name = 'newname');
 ALTER SUBSCRIPTION regress_testsub SET (password_required = false);
 ALTER SUBSCRIPTION regress_testsub SET (run_as_owner = true);
 \dRs+
-                                                                                                                     List of subscriptions
-      Name       |           Owner           | Enabled |     Publication     | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |           Conninfo           | Skip LSN 
------------------+---------------------------+---------+---------------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+------------------------------+----------
- regress_testsub | regress_subscription_user | f       | {testpub2,testpub3} | f      | parallel  | d                | f                | any    | f                 | t             | f        | off                | dbname=regress_doesnotexist2 | 0/0
+                                                                                                                                List of subscriptions
+      Name       |           Owner           | Enabled |     Publication     | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |           Conninfo           |  Skip LSN  
+-----------------+---------------------------+---------+---------------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+------------------------------+------------
+ regress_testsub | regress_subscription_user | f       | {testpub2,testpub3} | f      | parallel  | d                | f                | any    | f                 | t             | f        | f                  | off                | dbname=regress_doesnotexist2 | 0/00000000
 (1 row)
 
 ALTER SUBSCRIPTION regress_testsub SET (password_required = true);
@@ -176,10 +176,10 @@ ERROR:  unrecognized subscription parameter: "create_slot"
 -- ok
 ALTER SUBSCRIPTION regress_testsub SKIP (lsn = '0/12345');
 \dRs+
-                                                                                                                     List of subscriptions
-      Name       |           Owner           | Enabled |     Publication     | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |           Conninfo           | Skip LSN 
------------------+---------------------------+---------+---------------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+------------------------------+----------
- regress_testsub | regress_subscription_user | f       | {testpub2,testpub3} | f      | parallel  | d                | f                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist2 | 0/12345
+                                                                                                                                List of subscriptions
+      Name       |           Owner           | Enabled |     Publication     | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |           Conninfo           |  Skip LSN  
+-----------------+---------------------------+---------+---------------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+------------------------------+------------
+ regress_testsub | regress_subscription_user | f       | {testpub2,testpub3} | f      | parallel  | d                | f                | any    | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist2 | 0/00012345
 (1 row)
 
 -- ok - with lsn = NONE
@@ -188,10 +188,10 @@ ALTER SUBSCRIPTION regress_testsub SKIP (lsn = NONE);
 ALTER SUBSCRIPTION regress_testsub SKIP (lsn = '0/0');
 ERROR:  invalid WAL location (LSN): 0/0
 \dRs+
-                                                                                                                     List of subscriptions
-      Name       |           Owner           | Enabled |     Publication     | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |           Conninfo           | Skip LSN 
------------------+---------------------------+---------+---------------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+------------------------------+----------
- regress_testsub | regress_subscription_user | f       | {testpub2,testpub3} | f      | parallel  | d                | f                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist2 | 0/0
+                                                                                                                                List of subscriptions
+      Name       |           Owner           | Enabled |     Publication     | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |           Conninfo           |  Skip LSN  
+-----------------+---------------------------+---------+---------------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+------------------------------+------------
+ regress_testsub | regress_subscription_user | f       | {testpub2,testpub3} | f      | parallel  | d                | f                | any    | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist2 | 0/00000000
 (1 row)
 
 BEGIN;
@@ -223,10 +223,10 @@ ALTER SUBSCRIPTION regress_testsub_foo SET (synchronous_commit = foobar);
 ERROR:  invalid value for parameter "synchronous_commit": "foobar"
 HINT:  Available values: local, remote_write, remote_apply, on, off.
 \dRs+
-                                                                                                                       List of subscriptions
-        Name         |           Owner           | Enabled |     Publication     | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |           Conninfo           | Skip LSN 
----------------------+---------------------------+---------+---------------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+------------------------------+----------
- regress_testsub_foo | regress_subscription_user | f       | {testpub2,testpub3} | f      | parallel  | d                | f                | any    | t                 | f             | f        | local              | dbname=regress_doesnotexist2 | 0/0
+                                                                                                                                  List of subscriptions
+        Name         |           Owner           | Enabled |     Publication     | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |           Conninfo           |  Skip LSN  
+---------------------+---------------------------+---------+---------------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+------------------------------+------------
+ regress_testsub_foo | regress_subscription_user | f       | {testpub2,testpub3} | f      | parallel  | d                | f                | any    | t                 | f             | f        | f                  | local              | dbname=regress_doesnotexist2 | 0/00000000
 (1 row)
 
 -- rename back to keep the rest simple
@@ -255,19 +255,19 @@ CREATE SUBSCRIPTION regress_testsub CONNECTION 'dbname=regress_doesnotexist' PUB
 WARNING:  subscription was created, but is not connected
 HINT:  To initiate replication, you must manually create the replication slot, enable the subscription, and refresh the subscription.
 \dRs+
-                                                                                                                List of subscriptions
-      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |          Conninfo           | Skip LSN 
------------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+-----------------------------+----------
- regress_testsub | regress_subscription_user | f       | {testpub}   | t      | parallel  | d                | f                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist | 0/0
+                                                                                                                            List of subscriptions
+      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |          Conninfo           |  Skip LSN  
+-----------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+-----------------------------+------------
+ regress_testsub | regress_subscription_user | f       | {testpub}   | t      | parallel  | d                | f                | any    | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist | 0/00000000
 (1 row)
 
 ALTER SUBSCRIPTION regress_testsub SET (binary = false);
 ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
 \dRs+
-                                                                                                                List of subscriptions
-      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |          Conninfo           | Skip LSN 
------------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+-----------------------------+----------
- regress_testsub | regress_subscription_user | f       | {testpub}   | f      | parallel  | d                | f                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist | 0/0
+                                                                                                                            List of subscriptions
+      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |          Conninfo           |  Skip LSN  
+-----------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+-----------------------------+------------
+ regress_testsub | regress_subscription_user | f       | {testpub}   | f      | parallel  | d                | f                | any    | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist | 0/00000000
 (1 row)
 
 DROP SUBSCRIPTION regress_testsub;
@@ -279,27 +279,27 @@ CREATE SUBSCRIPTION regress_testsub CONNECTION 'dbname=regress_doesnotexist' PUB
 WARNING:  subscription was created, but is not connected
 HINT:  To initiate replication, you must manually create the replication slot, enable the subscription, and refresh the subscription.
 \dRs+
-                                                                                                                List of subscriptions
-      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |          Conninfo           | Skip LSN 
------------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+-----------------------------+----------
- regress_testsub | regress_subscription_user | f       | {testpub}   | f      | on        | d                | f                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist | 0/0
+                                                                                                                            List of subscriptions
+      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |          Conninfo           |  Skip LSN  
+-----------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+-----------------------------+------------
+ regress_testsub | regress_subscription_user | f       | {testpub}   | f      | on        | d                | f                | any    | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist | 0/00000000
 (1 row)
 
 ALTER SUBSCRIPTION regress_testsub SET (streaming = parallel);
 \dRs+
-                                                                                                                List of subscriptions
-      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |          Conninfo           | Skip LSN 
------------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+-----------------------------+----------
- regress_testsub | regress_subscription_user | f       | {testpub}   | f      | parallel  | d                | f                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist | 0/0
+                                                                                                                            List of subscriptions
+      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |          Conninfo           |  Skip LSN  
+-----------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+-----------------------------+------------
+ regress_testsub | regress_subscription_user | f       | {testpub}   | f      | parallel  | d                | f                | any    | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist | 0/00000000
 (1 row)
 
 ALTER SUBSCRIPTION regress_testsub SET (streaming = false);
 ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
 \dRs+
-                                                                                                                List of subscriptions
-      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |          Conninfo           | Skip LSN 
------------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+-----------------------------+----------
- regress_testsub | regress_subscription_user | f       | {testpub}   | f      | off       | d                | f                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist | 0/0
+                                                                                                                            List of subscriptions
+      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |          Conninfo           |  Skip LSN  
+-----------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+-----------------------------+------------
+ regress_testsub | regress_subscription_user | f       | {testpub}   | f      | off       | d                | f                | any    | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist | 0/00000000
 (1 row)
 
 -- fail - publication already exists
@@ -314,10 +314,10 @@ ALTER SUBSCRIPTION regress_testsub ADD PUBLICATION testpub1, testpub2 WITH (refr
 ALTER SUBSCRIPTION regress_testsub ADD PUBLICATION testpub1, testpub2 WITH (refresh = false);
 ERROR:  publication "testpub1" is already in subscription "regress_testsub"
 \dRs+
-                                                                                                                        List of subscriptions
-      Name       |           Owner           | Enabled |         Publication         | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |          Conninfo           | Skip LSN 
------------------+---------------------------+---------+-----------------------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+-----------------------------+----------
- regress_testsub | regress_subscription_user | f       | {testpub,testpub1,testpub2} | f      | off       | d                | f                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist | 0/0
+                                                                                                                                    List of subscriptions
+      Name       |           Owner           | Enabled |         Publication         | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |          Conninfo           |  Skip LSN  
+-----------------+---------------------------+---------+-----------------------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+-----------------------------+------------
+ regress_testsub | regress_subscription_user | f       | {testpub,testpub1,testpub2} | f      | off       | d                | f                | any    | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist | 0/00000000
 (1 row)
 
 -- fail - publication used more than once
@@ -332,10 +332,10 @@ ERROR:  publication "testpub3" is not in subscription "regress_testsub"
 -- ok - delete publications
 ALTER SUBSCRIPTION regress_testsub DROP PUBLICATION testpub1, testpub2 WITH (refresh = false);
 \dRs+
-                                                                                                                List of subscriptions
-      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |          Conninfo           | Skip LSN 
------------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+-----------------------------+----------
- regress_testsub | regress_subscription_user | f       | {testpub}   | f      | off       | d                | f                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist | 0/0
+                                                                                                                            List of subscriptions
+      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |          Conninfo           |  Skip LSN  
+-----------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+-----------------------------+------------
+ regress_testsub | regress_subscription_user | f       | {testpub}   | f      | off       | d                | f                | any    | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist | 0/00000000
 (1 row)
 
 DROP SUBSCRIPTION regress_testsub;
@@ -371,19 +371,19 @@ CREATE SUBSCRIPTION regress_testsub CONNECTION 'dbname=regress_doesnotexist' PUB
 WARNING:  subscription was created, but is not connected
 HINT:  To initiate replication, you must manually create the replication slot, enable the subscription, and refresh the subscription.
 \dRs+
-                                                                                                                List of subscriptions
-      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |          Conninfo           | Skip LSN 
------------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+-----------------------------+----------
- regress_testsub | regress_subscription_user | f       | {testpub}   | f      | parallel  | p                | f                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist | 0/0
+                                                                                                                            List of subscriptions
+      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |          Conninfo           |  Skip LSN  
+-----------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+-----------------------------+------------
+ regress_testsub | regress_subscription_user | f       | {testpub}   | f      | parallel  | p                | f                | any    | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist | 0/00000000
 (1 row)
 
 -- we can alter streaming when two_phase enabled
 ALTER SUBSCRIPTION regress_testsub SET (streaming = true);
 \dRs+
-                                                                                                                List of subscriptions
-      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |          Conninfo           | Skip LSN 
------------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+-----------------------------+----------
- regress_testsub | regress_subscription_user | f       | {testpub}   | f      | on        | p                | f                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist | 0/0
+                                                                                                                            List of subscriptions
+      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |          Conninfo           |  Skip LSN  
+-----------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+-----------------------------+------------
+ regress_testsub | regress_subscription_user | f       | {testpub}   | f      | on        | p                | f                | any    | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist | 0/00000000
 (1 row)
 
 ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
@@ -393,10 +393,10 @@ CREATE SUBSCRIPTION regress_testsub CONNECTION 'dbname=regress_doesnotexist' PUB
 WARNING:  subscription was created, but is not connected
 HINT:  To initiate replication, you must manually create the replication slot, enable the subscription, and refresh the subscription.
 \dRs+
-                                                                                                                List of subscriptions
-      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |          Conninfo           | Skip LSN 
------------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+-----------------------------+----------
- regress_testsub | regress_subscription_user | f       | {testpub}   | f      | on        | p                | f                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist | 0/0
+                                                                                                                            List of subscriptions
+      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |          Conninfo           |  Skip LSN  
+-----------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+-----------------------------+------------
+ regress_testsub | regress_subscription_user | f       | {testpub}   | f      | on        | p                | f                | any    | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist | 0/00000000
 (1 row)
 
 ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
@@ -409,18 +409,34 @@ CREATE SUBSCRIPTION regress_testsub CONNECTION 'dbname=regress_doesnotexist' PUB
 WARNING:  subscription was created, but is not connected
 HINT:  To initiate replication, you must manually create the replication slot, enable the subscription, and refresh the subscription.
 \dRs+
-                                                                                                                List of subscriptions
-      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |          Conninfo           | Skip LSN 
------------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+-----------------------------+----------
- regress_testsub | regress_subscription_user | f       | {testpub}   | f      | parallel  | d                | f                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist | 0/0
+                                                                                                                            List of subscriptions
+      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |          Conninfo           |  Skip LSN  
+-----------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+-----------------------------+------------
+ regress_testsub | regress_subscription_user | f       | {testpub}   | f      | parallel  | d                | f                | any    | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist | 0/00000000
 (1 row)
 
 ALTER SUBSCRIPTION regress_testsub SET (disable_on_error = true);
 \dRs+
-                                                                                                                List of subscriptions
-      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Synchronous commit |          Conninfo           | Skip LSN 
------------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+-----------------------------+----------
- regress_testsub | regress_subscription_user | f       | {testpub}   | f      | parallel  | d                | t                | any    | t                 | f             | f        | off                | dbname=regress_doesnotexist | 0/0
+                                                                                                                            List of subscriptions
+      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |          Conninfo           |  Skip LSN  
+-----------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+-----------------------------+------------
+ regress_testsub | regress_subscription_user | f       | {testpub}   | f      | parallel  | d                | t                | any    | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist | 0/00000000
+(1 row)
+
+ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
+DROP SUBSCRIPTION regress_testsub;
+-- fail - retain_dead_tuples must be boolean
+CREATE SUBSCRIPTION regress_testsub CONNECTION 'dbname=regress_doesnotexist' PUBLICATION testpub WITH (connect = false, retain_dead_tuples = foo);
+ERROR:  retain_dead_tuples requires a Boolean value
+-- ok
+CREATE SUBSCRIPTION regress_testsub CONNECTION 'dbname=regress_doesnotexist' PUBLICATION testpub WITH (connect = false, retain_dead_tuples = false);
+WARNING:  subscription was created, but is not connected
+HINT:  To initiate replication, you must manually create the replication slot, enable the subscription, and refresh the subscription.
+\dRs+
+                                                                                                                            List of subscriptions
+      Name       |           Owner           | Enabled | Publication | Binary | Streaming | Two-phase commit | Disable on error | Origin | Password required | Run as owner? | Failover | Retain dead tuples | Synchronous commit |          Conninfo           |  Skip LSN  
+-----------------+---------------------------+---------+-------------+--------+-----------+------------------+------------------+--------+-------------------+---------------+----------+--------------------+--------------------+-----------------------------+------------
+ regress_testsub | regress_subscription_user | f       | {testpub}   | f      | parallel  | d                | f                | any    | t                 | f             | f        | f                  | off                | dbname=regress_doesnotexist | 0/00000000
 (1 row)
 
 ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
diff --git a/src/test/regress/expected/subselect.out b/src/test/regress/expected/subselect.out
index 40d8056fcea40..18fed63e7381a 100644
--- a/src/test/regress/expected/subselect.out
+++ b/src/test/regress/expected/subselect.out
@@ -2127,30 +2127,30 @@ explain (verbose, costs off)
 select ss2.* from
   int8_tbl t1 left join
   (int8_tbl t2 left join
-   (select coalesce(q1) as x, * from int8_tbl t3) ss1 on t2.q1 = ss1.q2 inner join
+   (select coalesce(q1, q1) as x, * from int8_tbl t3) ss1 on t2.q1 = ss1.q2 inner join
    lateral (select ss1.x as y, * from int8_tbl t4) ss2 on t2.q2 = ss2.q1)
   on t1.q2 = ss2.q1
 order by 1, 2, 3;
-                           QUERY PLAN                           
-----------------------------------------------------------------
+                              QUERY PLAN                               
+-----------------------------------------------------------------------
  Sort
-   Output: (COALESCE(t3.q1)), t4.q1, t4.q2
-   Sort Key: (COALESCE(t3.q1)), t4.q1, t4.q2
+   Output: (COALESCE(t3.q1, t3.q1)), t4.q1, t4.q2
+   Sort Key: (COALESCE(t3.q1, t3.q1)), t4.q1, t4.q2
    ->  Hash Right Join
-         Output: (COALESCE(t3.q1)), t4.q1, t4.q2
+         Output: (COALESCE(t3.q1, t3.q1)), t4.q1, t4.q2
          Hash Cond: (t4.q1 = t1.q2)
          ->  Hash Join
-               Output: (COALESCE(t3.q1)), t4.q1, t4.q2
+               Output: (COALESCE(t3.q1, t3.q1)), t4.q1, t4.q2
                Hash Cond: (t2.q2 = t4.q1)
                ->  Hash Left Join
-                     Output: t2.q2, (COALESCE(t3.q1))
+                     Output: t2.q2, (COALESCE(t3.q1, t3.q1))
                      Hash Cond: (t2.q1 = t3.q2)
                      ->  Seq Scan on public.int8_tbl t2
                            Output: t2.q1, t2.q2
                      ->  Hash
-                           Output: t3.q2, (COALESCE(t3.q1))
+                           Output: t3.q2, (COALESCE(t3.q1, t3.q1))
                            ->  Seq Scan on public.int8_tbl t3
-                                 Output: t3.q2, COALESCE(t3.q1)
+                                 Output: t3.q2, COALESCE(t3.q1, t3.q1)
                ->  Hash
                      Output: t4.q1, t4.q2
                      ->  Seq Scan on public.int8_tbl t4
@@ -2164,7 +2164,7 @@ order by 1, 2, 3;
 select ss2.* from
   int8_tbl t1 left join
   (int8_tbl t2 left join
-   (select coalesce(q1) as x, * from int8_tbl t3) ss1 on t2.q1 = ss1.q2 inner join
+   (select coalesce(q1, q1) as x, * from int8_tbl t3) ss1 on t2.q1 = ss1.q2 inner join
    lateral (select ss1.x as y, * from int8_tbl t4) ss2 on t2.q2 = ss2.q1)
   on t1.q2 = ss2.q1
 order by 1, 2, 3;
@@ -2201,32 +2201,32 @@ explain (verbose, costs off)
 select ss2.* from
   int8_tbl t1 left join
   (int8_tbl t2 left join
-   (select coalesce(q1) as x, * from int8_tbl t3) ss1 on t2.q1 = ss1.q2 left join
+   (select coalesce(q1, q1) as x, * from int8_tbl t3) ss1 on t2.q1 = ss1.q2 left join
    lateral (select ss1.x as y, * from int8_tbl t4) ss2 on t2.q2 = ss2.q1)
   on t1.q2 = ss2.q1
 order by 1, 2, 3;
-                           QUERY PLAN                           
-----------------------------------------------------------------
+                              QUERY PLAN                               
+-----------------------------------------------------------------------
  Sort
-   Output: ((COALESCE(t3.q1))), t4.q1, t4.q2
-   Sort Key: ((COALESCE(t3.q1))), t4.q1, t4.q2
+   Output: ((COALESCE(t3.q1, t3.q1))), t4.q1, t4.q2
+   Sort Key: ((COALESCE(t3.q1, t3.q1))), t4.q1, t4.q2
    ->  Hash Right Join
-         Output: ((COALESCE(t3.q1))), t4.q1, t4.q2
+         Output: ((COALESCE(t3.q1, t3.q1))), t4.q1, t4.q2
          Hash Cond: (t4.q1 = t1.q2)
          ->  Nested Loop
-               Output: t4.q1, t4.q2, ((COALESCE(t3.q1)))
+               Output: t4.q1, t4.q2, ((COALESCE(t3.q1, t3.q1)))
                Join Filter: (t2.q2 = t4.q1)
                ->  Hash Left Join
-                     Output: t2.q2, (COALESCE(t3.q1))
+                     Output: t2.q2, (COALESCE(t3.q1, t3.q1))
                      Hash Cond: (t2.q1 = t3.q2)
                      ->  Seq Scan on public.int8_tbl t2
                            Output: t2.q1, t2.q2
                      ->  Hash
-                           Output: t3.q2, (COALESCE(t3.q1))
+                           Output: t3.q2, (COALESCE(t3.q1, t3.q1))
                            ->  Seq Scan on public.int8_tbl t3
-                                 Output: t3.q2, COALESCE(t3.q1)
+                                 Output: t3.q2, COALESCE(t3.q1, t3.q1)
                ->  Seq Scan on public.int8_tbl t4
-                     Output: t4.q1, t4.q2, (COALESCE(t3.q1))
+                     Output: t4.q1, t4.q2, (COALESCE(t3.q1, t3.q1))
          ->  Hash
                Output: t1.q2
                ->  Seq Scan on public.int8_tbl t1
@@ -2236,7 +2236,7 @@ order by 1, 2, 3;
 select ss2.* from
   int8_tbl t1 left join
   (int8_tbl t2 left join
-   (select coalesce(q1) as x, * from int8_tbl t3) ss1 on t2.q1 = ss1.q2 left join
+   (select coalesce(q1, q1) as x, * from int8_tbl t3) ss1 on t2.q1 = ss1.q2 left join
    lateral (select ss1.x as y, * from int8_tbl t4) ss2 on t2.q2 = ss2.q1)
   on t1.q2 = ss2.q1
 order by 1, 2, 3;
diff --git a/src/test/regress/expected/triggers.out b/src/test/regress/expected/triggers.out
index 2bf0e77d61ecb..872b9100e1a01 100644
--- a/src/test/regress/expected/triggers.out
+++ b/src/test/regress/expected/triggers.out
@@ -2280,6 +2280,27 @@ select * from parted;
 drop table parted;
 drop function parted_trigfunc();
 --
+-- Constraint triggers
+--
+create constraint trigger crtr
+  after insert on foo not valid
+  for each row execute procedure foo ();
+ERROR:  constraint triggers cannot be marked NOT VALID
+LINE 2:   after insert on foo not valid
+                              ^
+create constraint trigger crtr
+  after insert on foo no inherit
+  for each row execute procedure foo ();
+ERROR:  constraint triggers cannot be marked NO INHERIT
+LINE 2:   after insert on foo no inherit
+                              ^
+create constraint trigger crtr
+  after insert on foo not enforced
+  for each row execute procedure foo ();
+ERROR:  constraint triggers cannot be marked NOT ENFORCED
+LINE 2:   after insert on foo not enforced
+                              ^
+--
 -- Constraint triggers and partitioned tables
 create table parted_constr_ancestor (a int, b text)
   partition by range (b);
@@ -2294,7 +2315,7 @@ create constraint trigger parted_trig after insert on parted_constr_ancestor
   deferrable
   for each row execute procedure trigger_notice_ab();
 create constraint trigger parted_trig_two after insert on parted_constr
-  deferrable initially deferred
+  deferrable initially deferred enforced
   for each row when (bark(new.b) AND new.a % 2 = 1)
   execute procedure trigger_notice_ab();
 -- The immediate constraint is fired immediately; the WHEN clause of the
diff --git a/src/test/regress/expected/type_sanity.out b/src/test/regress/expected/type_sanity.out
index dd0c52ab08b50..943e56506bf1b 100644
--- a/src/test/regress/expected/type_sanity.out
+++ b/src/test/regress/expected/type_sanity.out
@@ -711,6 +711,7 @@ CREATE TABLE tab_core_types AS SELECT
   'regtype'::regtype type,
   'pg_monitor'::regrole,
   'pg_class'::regclass::oid,
+  'template1'::regdatabase,
   '(1,1)'::tid, '2'::xid, '3'::cid,
   '10:20:10,14,15'::txid_snapshot,
   '10:20:10,14,15'::pg_snapshot,
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
index a424be2a6bf0f..fbffc67ae6013 100644
--- a/src/test/regress/parallel_schedule
+++ b/src/test/regress/parallel_schedule
@@ -123,7 +123,7 @@ test: plancache limit plpgsql copy2 temp domain rangefuncs prepare conversion tr
 # The stats test resets stats, so nothing else needing stats access can be in
 # this group.
 # ----------
-test: partition_join partition_prune reloptions hash_part indexing partition_aggregate partition_info tuplesort explain compression memoize stats predicate numa
+test: partition_join partition_prune reloptions hash_part indexing partition_aggregate partition_info tuplesort explain compression compression_lz4 memoize stats predicate numa
 
 # event_trigger depends on create_am and cannot run concurrently with
 # any test that runs DDL
diff --git a/src/test/regress/sql/alter_table.sql b/src/test/regress/sql/alter_table.sql
index 41cff198e183c..fc6e36d0e7882 100644
--- a/src/test/regress/sql/alter_table.sql
+++ b/src/test/regress/sql/alter_table.sql
@@ -3074,6 +3074,14 @@ drop table attbl, atref;
 create table attbl(a int);
 create table atref(b attbl check ((b).a is not null));
 alter table attbl alter column a type numeric;  -- someday this should work
+alter table atref drop constraint atref_b_check;
+
+create statistics atref_stat on ((b).a is not null) from atref;
+alter table attbl alter column a type numeric;  -- someday this should work
+drop statistics atref_stat;
+
+create index atref_idx on atref (((b).a));
+alter table attbl alter column a type numeric;  -- someday this should work
 drop table attbl, atref;
 
 /* End test case for bug #18970 */
diff --git a/src/test/regress/sql/btree_index.sql b/src/test/regress/sql/btree_index.sql
index 68c61dbc7d19c..6aaaa386abcec 100644
--- a/src/test/regress/sql/btree_index.sql
+++ b/src/test/regress/sql/btree_index.sql
@@ -143,38 +143,83 @@ SELECT proname, proargtypes, pronamespace
 ORDER BY proname DESC, proargtypes DESC, pronamespace DESC LIMIT 1;
 
 --
--- Add coverage for RowCompare quals whose rhs row has a NULL that ends scan
+-- Forwards scan RowCompare qual whose row arg has a NULL that affects our
+-- initial positioning strategy
 --
 explain (costs off)
 SELECT proname, proargtypes, pronamespace
    FROM pg_proc
-   WHERE proname = 'abs' AND (proname, proargtypes) < ('abs', NULL)
+   WHERE (proname, proargtypes) >= ('abs', NULL) AND proname <= 'abs'
 ORDER BY proname, proargtypes, pronamespace;
 
 SELECT proname, proargtypes, pronamespace
    FROM pg_proc
-   WHERE proname = 'abs' AND (proname, proargtypes) < ('abs', NULL)
+   WHERE (proname, proargtypes) >= ('abs', NULL) AND proname <= 'abs'
 ORDER BY proname, proargtypes, pronamespace;
 
 --
--- Add coverage for backwards scan RowCompare quals whose rhs row has a NULL
--- that ends scan
+-- Forwards scan RowCompare quals whose row arg has a NULL that ends scan
 --
 explain (costs off)
 SELECT proname, proargtypes, pronamespace
    FROM pg_proc
-   WHERE proname = 'abs' AND (proname, proargtypes) > ('abs', NULL)
+   WHERE proname >= 'abs' AND (proname, proargtypes) < ('abs', NULL)
+ORDER BY proname, proargtypes, pronamespace;
+
+SELECT proname, proargtypes, pronamespace
+   FROM pg_proc
+   WHERE proname >= 'abs' AND (proname, proargtypes) < ('abs', NULL)
+ORDER BY proname, proargtypes, pronamespace;
+
+--
+-- Backwards scan RowCompare qual whose row arg has a NULL that affects our
+-- initial positioning strategy
+--
+explain (costs off)
+SELECT proname, proargtypes, pronamespace
+   FROM pg_proc
+   WHERE proname >= 'abs' AND (proname, proargtypes) <= ('abs', NULL)
 ORDER BY proname DESC, proargtypes DESC, pronamespace DESC;
 
 SELECT proname, proargtypes, pronamespace
    FROM pg_proc
-   WHERE proname = 'abs' AND (proname, proargtypes) > ('abs', NULL)
+   WHERE proname >= 'abs' AND (proname, proargtypes) <= ('abs', NULL)
 ORDER BY proname DESC, proargtypes DESC, pronamespace DESC;
 
 --
--- Add coverage for recheck of > key following array advancement on previous
--- (left sibling) page that used a high key whose attribute value corresponding
--- to the > key was -inf (due to being truncated when the high key was created).
+-- Backwards scan RowCompare qual whose row arg has a NULL that ends scan
+--
+explain (costs off)
+SELECT proname, proargtypes, pronamespace
+   FROM pg_proc
+   WHERE (proname, proargtypes) > ('abs', NULL) AND proname <= 'abs'
+ORDER BY proname DESC, proargtypes DESC, pronamespace DESC;
+
+SELECT proname, proargtypes, pronamespace
+   FROM pg_proc
+   WHERE (proname, proargtypes) > ('abs', NULL) AND proname <= 'abs'
+ORDER BY proname DESC, proargtypes DESC, pronamespace DESC;
+
+-- Makes B-Tree preprocessing deal with unmarking redundant keys that were
+-- initially marked required (test case relies on current row compare
+-- preprocessing limitations)
+explain (costs off)
+SELECT proname, proargtypes, pronamespace
+   FROM pg_proc
+   WHERE proname = 'zzzzzz' AND (proname, proargtypes) > ('abs', NULL)
+   AND pronamespace IN (1, 2, 3) AND proargtypes IN ('26 23', '5077')
+ORDER BY proname, proargtypes, pronamespace;
+
+SELECT proname, proargtypes, pronamespace
+   FROM pg_proc
+   WHERE proname = 'zzzzzz' AND (proname, proargtypes) > ('abs', NULL)
+   AND pronamespace IN (1, 2, 3) AND proargtypes IN ('26 23', '5077')
+ORDER BY proname, proargtypes, pronamespace;
+
+--
+-- Performs a recheck of > key following array advancement on previous (left
+-- sibling) page that used a high key whose attribute value corresponding to
+-- the > key was -inf (due to being truncated when the high key was created).
 --
 -- XXX This relies on the assumption that tenk1_thous_tenthous has a truncated
 -- high key "(183, -inf)" on the first page that we'll scan.  The test will only
diff --git a/src/test/regress/sql/compression.sql b/src/test/regress/sql/compression.sql
index 490595fcfb263..ce5ea37a660ce 100644
--- a/src/test/regress/sql/compression.sql
+++ b/src/test/regress/sql/compression.sql
@@ -1,3 +1,8 @@
+-- Default set of tests for TOAST compression, independent on compression
+-- methods supported by the build.
+
+CREATE SCHEMA pglz;
+SET search_path TO pglz, public;
 \set HIDE_TOAST_COMPRESSION false
 
 -- ensure we get stable results regardless of installation's default
@@ -8,53 +13,27 @@ CREATE TABLE cmdata(f1 text COMPRESSION pglz);
 CREATE INDEX idx ON cmdata(f1);
 INSERT INTO cmdata VALUES(repeat('1234567890', 1000));
 \d+ cmdata
-CREATE TABLE cmdata1(f1 TEXT COMPRESSION lz4);
-INSERT INTO cmdata1 VALUES(repeat('1234567890', 1004));
-\d+ cmdata1
 
 -- verify stored compression method in the data
 SELECT pg_column_compression(f1) FROM cmdata;
-SELECT pg_column_compression(f1) FROM cmdata1;
 
 -- decompress data slice
 SELECT SUBSTR(f1, 200, 5) FROM cmdata;
-SELECT SUBSTR(f1, 2000, 50) FROM cmdata1;
 
 -- copy with table creation
 SELECT * INTO cmmove1 FROM cmdata;
 \d+ cmmove1
 SELECT pg_column_compression(f1) FROM cmmove1;
 
--- copy to existing table
-CREATE TABLE cmmove3(f1 text COMPRESSION pglz);
-INSERT INTO cmmove3 SELECT * FROM cmdata;
-INSERT INTO cmmove3 SELECT * FROM cmdata1;
-SELECT pg_column_compression(f1) FROM cmmove3;
-
--- test LIKE INCLUDING COMPRESSION
-CREATE TABLE cmdata2 (LIKE cmdata1 INCLUDING COMPRESSION);
-\d+ cmdata2
-DROP TABLE cmdata2;
-
 -- try setting compression for incompressible data type
 CREATE TABLE cmdata2 (f1 int COMPRESSION pglz);
 
--- update using datum from different table
-CREATE TABLE cmmove2(f1 text COMPRESSION pglz);
-INSERT INTO cmmove2 VALUES (repeat('1234567890', 1004));
-SELECT pg_column_compression(f1) FROM cmmove2;
-UPDATE cmmove2 SET f1 = cmdata1.f1 FROM cmdata1;
-SELECT pg_column_compression(f1) FROM cmmove2;
-
 -- test externally stored compressed data
 CREATE OR REPLACE FUNCTION large_val() RETURNS TEXT LANGUAGE SQL AS
 'select array_agg(fipshash(g::text))::text from generate_series(1, 256) g';
 CREATE TABLE cmdata2 (f1 text COMPRESSION pglz);
 INSERT INTO cmdata2 SELECT large_val() || repeat('a', 4000);
 SELECT pg_column_compression(f1) FROM cmdata2;
-INSERT INTO cmdata1 SELECT large_val() || repeat('a', 4000);
-SELECT pg_column_compression(f1) FROM cmdata1;
-SELECT SUBSTR(f1, 200, 5) FROM cmdata1;
 SELECT SUBSTR(f1, 200, 5) FROM cmdata2;
 DROP TABLE cmdata2;
 
@@ -76,76 +55,31 @@ ALTER TABLE cmdata2 ALTER COLUMN f1 SET STORAGE plain;
 INSERT INTO cmdata2 VALUES (repeat('123456789', 800));
 SELECT pg_column_compression(f1) FROM cmdata2;
 
--- test compression with materialized view
-CREATE MATERIALIZED VIEW compressmv(x) AS SELECT * FROM cmdata1;
-\d+ compressmv
-SELECT pg_column_compression(f1) FROM cmdata1;
-SELECT pg_column_compression(x) FROM compressmv;
-
--- test compression with partition
-CREATE TABLE cmpart(f1 text COMPRESSION lz4) PARTITION BY HASH(f1);
-CREATE TABLE cmpart1 PARTITION OF cmpart FOR VALUES WITH (MODULUS 2, REMAINDER 0);
-CREATE TABLE cmpart2(f1 text COMPRESSION pglz);
-
-ALTER TABLE cmpart ATTACH PARTITION cmpart2 FOR VALUES WITH (MODULUS 2, REMAINDER 1);
-INSERT INTO cmpart VALUES (repeat('123456789', 1004));
-INSERT INTO cmpart VALUES (repeat('123456789', 4004));
-SELECT pg_column_compression(f1) FROM cmpart1;
-SELECT pg_column_compression(f1) FROM cmpart2;
-
 -- test compression with inheritance
-CREATE TABLE cminh() INHERITS(cmdata, cmdata1); -- error
-CREATE TABLE cminh(f1 TEXT COMPRESSION lz4) INHERITS(cmdata); -- error
 CREATE TABLE cmdata3(f1 text);
 CREATE TABLE cminh() INHERITS (cmdata, cmdata3);
 
 -- test default_toast_compression GUC
+-- suppress machine-dependent details
+\set VERBOSITY terse
 SET default_toast_compression = '';
 SET default_toast_compression = 'I do not exist compression';
-SET default_toast_compression = 'lz4';
 SET default_toast_compression = 'pglz';
-
--- test alter compression method
-ALTER TABLE cmdata ALTER COLUMN f1 SET COMPRESSION lz4;
-INSERT INTO cmdata VALUES (repeat('123456789', 4004));
-\d+ cmdata
-SELECT pg_column_compression(f1) FROM cmdata;
+\set VERBOSITY default
 
 ALTER TABLE cmdata2 ALTER COLUMN f1 SET COMPRESSION default;
 \d+ cmdata2
 
--- test alter compression method for materialized views
-ALTER MATERIALIZED VIEW compressmv ALTER COLUMN x SET COMPRESSION lz4;
-\d+ compressmv
-
--- test alter compression method for partitioned tables
-ALTER TABLE cmpart1 ALTER COLUMN f1 SET COMPRESSION pglz;
-ALTER TABLE cmpart2 ALTER COLUMN f1 SET COMPRESSION lz4;
-
--- new data should be compressed with the current compression method
-INSERT INTO cmpart VALUES (repeat('123456789', 1004));
-INSERT INTO cmpart VALUES (repeat('123456789', 4004));
-SELECT pg_column_compression(f1) FROM cmpart1;
-SELECT pg_column_compression(f1) FROM cmpart2;
+DROP TABLE cmdata2;
 
 -- VACUUM FULL does not recompress
 SELECT pg_column_compression(f1) FROM cmdata;
 VACUUM FULL cmdata;
 SELECT pg_column_compression(f1) FROM cmdata;
 
--- test expression index
-DROP TABLE cmdata2;
-CREATE TABLE cmdata2 (f1 TEXT COMPRESSION pglz, f2 TEXT COMPRESSION lz4);
-CREATE UNIQUE INDEX idx1 ON cmdata2 ((f1 || f2));
-INSERT INTO cmdata2 VALUES((SELECT array_agg(fipshash(g::TEXT))::TEXT FROM
-generate_series(1, 50) g), VERSION());
-
 -- check data is ok
 SELECT length(f1) FROM cmdata;
-SELECT length(f1) FROM cmdata1;
 SELECT length(f1) FROM cmmove1;
-SELECT length(f1) FROM cmmove2;
-SELECT length(f1) FROM cmmove3;
 
 CREATE TABLE badcompresstbl (a text COMPRESSION I_Do_Not_Exist_Compression); -- fails
 CREATE TABLE badcompresstbl (a text);
diff --git a/src/test/regress/sql/compression_lz4.sql b/src/test/regress/sql/compression_lz4.sql
new file mode 100644
index 0000000000000..3849f8618dee4
--- /dev/null
+++ b/src/test/regress/sql/compression_lz4.sql
@@ -0,0 +1,129 @@
+-- Tests for TOAST compression with lz4
+
+SELECT NOT(enumvals @> '{lz4}') AS skip_test FROM pg_settings WHERE
+  name = 'default_toast_compression' \gset
+\if :skip_test
+   \echo '*** skipping TOAST tests with lz4 (not supported) ***'
+   \quit
+\endif
+
+CREATE SCHEMA lz4;
+SET search_path TO lz4, public;
+
+\set HIDE_TOAST_COMPRESSION false
+
+-- Ensure we get stable results regardless of the installation's default.
+-- We rely on this GUC value for a few tests.
+SET default_toast_compression = 'pglz';
+
+-- test creating table with compression method
+CREATE TABLE cmdata_pglz(f1 text COMPRESSION pglz);
+CREATE INDEX idx ON cmdata_pglz(f1);
+INSERT INTO cmdata_pglz VALUES(repeat('1234567890', 1000));
+\d+ cmdata
+CREATE TABLE cmdata_lz4(f1 TEXT COMPRESSION lz4);
+INSERT INTO cmdata_lz4 VALUES(repeat('1234567890', 1004));
+\d+ cmdata1
+
+-- verify stored compression method in the data
+SELECT pg_column_compression(f1) FROM cmdata_lz4;
+
+-- decompress data slice
+SELECT SUBSTR(f1, 200, 5) FROM cmdata_pglz;
+SELECT SUBSTR(f1, 2000, 50) FROM cmdata_lz4;
+
+-- copy with table creation
+SELECT * INTO cmmove1 FROM cmdata_lz4;
+\d+ cmmove1
+SELECT pg_column_compression(f1) FROM cmmove1;
+
+-- test LIKE INCLUDING COMPRESSION.  The GUC default_toast_compression
+-- has no effect, the compression method from the table being copied.
+CREATE TABLE cmdata2 (LIKE cmdata_lz4 INCLUDING COMPRESSION);
+\d+ cmdata2
+DROP TABLE cmdata2;
+
+-- copy to existing table
+CREATE TABLE cmmove3(f1 text COMPRESSION pglz);
+INSERT INTO cmmove3 SELECT * FROM cmdata_pglz;
+INSERT INTO cmmove3 SELECT * FROM cmdata_lz4;
+SELECT pg_column_compression(f1) FROM cmmove3;
+
+-- update using datum from different table with LZ4 data.
+CREATE TABLE cmmove2(f1 text COMPRESSION pglz);
+INSERT INTO cmmove2 VALUES (repeat('1234567890', 1004));
+SELECT pg_column_compression(f1) FROM cmmove2;
+UPDATE cmmove2 SET f1 = cmdata_lz4.f1 FROM cmdata_lz4;
+SELECT pg_column_compression(f1) FROM cmmove2;
+
+-- test externally stored compressed data
+CREATE OR REPLACE FUNCTION large_val_lz4() RETURNS TEXT LANGUAGE SQL AS
+'select array_agg(fipshash(g::text))::text from generate_series(1, 256) g';
+CREATE TABLE cmdata2 (f1 text COMPRESSION lz4);
+INSERT INTO cmdata2 SELECT large_val_lz4() || repeat('a', 4000);
+SELECT pg_column_compression(f1) FROM cmdata2;
+SELECT SUBSTR(f1, 200, 5) FROM cmdata2;
+DROP TABLE cmdata2;
+DROP FUNCTION large_val_lz4;
+
+-- test compression with materialized view
+CREATE MATERIALIZED VIEW compressmv(x) AS SELECT * FROM cmdata_lz4;
+\d+ compressmv
+SELECT pg_column_compression(f1) FROM cmdata_lz4;
+SELECT pg_column_compression(x) FROM compressmv;
+
+-- test compression with partition
+CREATE TABLE cmpart(f1 text COMPRESSION lz4) PARTITION BY HASH(f1);
+CREATE TABLE cmpart1 PARTITION OF cmpart FOR VALUES WITH (MODULUS 2, REMAINDER 0);
+CREATE TABLE cmpart2(f1 text COMPRESSION pglz);
+
+ALTER TABLE cmpart ATTACH PARTITION cmpart2 FOR VALUES WITH (MODULUS 2, REMAINDER 1);
+INSERT INTO cmpart VALUES (repeat('123456789', 1004));
+INSERT INTO cmpart VALUES (repeat('123456789', 4004));
+SELECT pg_column_compression(f1) FROM cmpart1;
+SELECT pg_column_compression(f1) FROM cmpart2;
+
+-- test compression with inheritance
+CREATE TABLE cminh() INHERITS(cmdata_pglz, cmdata_lz4); -- error
+CREATE TABLE cminh(f1 TEXT COMPRESSION lz4) INHERITS(cmdata_pglz); -- error
+CREATE TABLE cmdata3(f1 text);
+CREATE TABLE cminh() INHERITS (cmdata_pglz, cmdata3);
+
+-- test default_toast_compression GUC
+SET default_toast_compression = 'lz4';
+
+-- test alter compression method
+ALTER TABLE cmdata_pglz ALTER COLUMN f1 SET COMPRESSION lz4;
+INSERT INTO cmdata_pglz VALUES (repeat('123456789', 4004));
+\d+ cmdata
+SELECT pg_column_compression(f1) FROM cmdata_pglz;
+ALTER TABLE cmdata_pglz ALTER COLUMN f1 SET COMPRESSION pglz;
+
+-- test alter compression method for materialized views
+ALTER MATERIALIZED VIEW compressmv ALTER COLUMN x SET COMPRESSION lz4;
+\d+ compressmv
+
+-- test alter compression method for partitioned tables
+ALTER TABLE cmpart1 ALTER COLUMN f1 SET COMPRESSION pglz;
+ALTER TABLE cmpart2 ALTER COLUMN f1 SET COMPRESSION lz4;
+
+-- new data should be compressed with the current compression method
+INSERT INTO cmpart VALUES (repeat('123456789', 1004));
+INSERT INTO cmpart VALUES (repeat('123456789', 4004));
+SELECT pg_column_compression(f1) FROM cmpart1;
+SELECT pg_column_compression(f1) FROM cmpart2;
+
+-- test expression index
+CREATE TABLE cmdata2 (f1 TEXT COMPRESSION pglz, f2 TEXT COMPRESSION lz4);
+CREATE UNIQUE INDEX idx1 ON cmdata2 ((f1 || f2));
+INSERT INTO cmdata2 VALUES((SELECT array_agg(fipshash(g::TEXT))::TEXT FROM
+generate_series(1, 50) g), VERSION());
+
+-- check data is ok
+SELECT length(f1) FROM cmdata_pglz;
+SELECT length(f1) FROM cmdata_lz4;
+SELECT length(f1) FROM cmmove1;
+SELECT length(f1) FROM cmmove2;
+SELECT length(f1) FROM cmmove3;
+
+\set HIDE_TOAST_COMPRESSION true
diff --git a/src/test/regress/sql/constraints.sql b/src/test/regress/sql/constraints.sql
index 12668f0e0ce0f..1f6dc8fd69f6d 100644
--- a/src/test/regress/sql/constraints.sql
+++ b/src/test/regress/sql/constraints.sql
@@ -537,6 +537,9 @@ CREATE TABLE UNIQUE_NOTEN_TBL(i int UNIQUE NOT ENFORCED);
 ALTER TABLE unique_tbl ALTER CONSTRAINT unique_tbl_i_key ENFORCED;
 ALTER TABLE unique_tbl ALTER CONSTRAINT unique_tbl_i_key NOT ENFORCED;
 
+-- can't make an existing constraint NOT VALID
+ALTER TABLE unique_tbl ALTER CONSTRAINT unique_tbl_i_key NOT VALID;
+
 DROP TABLE unique_tbl;
 
 --
@@ -1040,3 +1043,9 @@ DROP DOMAIN constraint_comments_dom;
 
 DROP ROLE regress_constraint_comments;
 DROP ROLE regress_constraint_comments_noaccess;
+
+-- Leave some constraints for the pg_upgrade test to pick up
+CREATE DOMAIN constraint_comments_dom AS int;
+
+ALTER DOMAIN constraint_comments_dom ADD CONSTRAINT inv_ck CHECK (value > 0) NOT VALID;
+COMMENT ON CONSTRAINT inv_ck ON DOMAIN constraint_comments_dom IS 'comment on invalid constraint';
diff --git a/src/test/regress/sql/copy.sql b/src/test/regress/sql/copy.sql
index f0b88a23db853..a1316c73bac69 100644
--- a/src/test/regress/sql/copy.sql
+++ b/src/test/regress/sql/copy.sql
@@ -94,6 +94,36 @@ this is just a line full of junk that would error out if parsed
 
 copy copytest4 to stdout (header);
 
+-- test multi-line header line feature
+
+create temp table copytest5 (c1 int);
+
+copy copytest5 from stdin (format csv, header 2);
+this is a first header line.
+this is a second header line.
+1
+2
+\.
+copy copytest5 to stdout (header);
+
+truncate copytest5;
+copy copytest5 from stdin (format csv, header 4);
+this is a first header line.
+this is a second header line.
+1
+2
+\.
+select count(*) from copytest5;
+
+truncate copytest5;
+copy copytest5 from stdin (format csv, header 5);
+this is a first header line.
+this is a second header line.
+1
+2
+\.
+select count(*) from copytest5;
+
 -- test copy from with a partitioned table
 create table parted_copytest (
 	a int,
diff --git a/src/test/regress/sql/copy2.sql b/src/test/regress/sql/copy2.sql
index 45273557ce040..cef45868db511 100644
--- a/src/test/regress/sql/copy2.sql
+++ b/src/test/regress/sql/copy2.sql
@@ -90,6 +90,9 @@ COPY x to stdout (format BINARY, on_error unsupported);
 COPY x from stdin (log_verbosity unsupported);
 COPY x from stdin with (reject_limit 1);
 COPY x from stdin with (on_error ignore, reject_limit 0);
+COPY x from stdin with (header -1);
+COPY x from stdin with (header 2.5);
+COPY x to stdout with (header 2);
 
 -- too many columns in column list: should fail
 COPY x (a, b, c, d, e, d, c) from stdin;
diff --git a/src/test/regress/sql/create_index.sql b/src/test/regress/sql/create_index.sql
index e21ff426519b0..eabc9623b2061 100644
--- a/src/test/regress/sql/create_index.sql
+++ b/src/test/regress/sql/create_index.sql
@@ -635,7 +635,7 @@ DROP TABLE cwi_test;
 CREATE TABLE syscol_table (a INT);
 
 -- System columns cannot be indexed
-CREATE INDEX ON syscolcol_table (ctid);
+CREATE INDEX ON syscol_table (ctid);
 
 -- nor used in expressions
 CREATE INDEX ON syscol_table ((ctid >= '(1000,0)'));
diff --git a/src/test/regress/sql/domain.sql b/src/test/regress/sql/domain.sql
index b752a63ab5f69..b8f5a6397121a 100644
--- a/src/test/regress/sql/domain.sql
+++ b/src/test/regress/sql/domain.sql
@@ -602,6 +602,9 @@ insert into domain_test values (1, 2);
 -- should fail
 alter table domain_test add column c str_domain;
 
+-- disallow duplicated not-null constraints
+create domain int_domain1 as int constraint nn1 not null constraint nn2 not null;
+
 create domain str_domain2 as text check (value <> 'foo') default 'foo';
 
 -- should fail
diff --git a/src/test/regress/sql/foreign_key.sql b/src/test/regress/sql/foreign_key.sql
index cfcecb4e911ad..39174ad1eb9a0 100644
--- a/src/test/regress/sql/foreign_key.sql
+++ b/src/test/regress/sql/foreign_key.sql
@@ -1296,7 +1296,7 @@ UPDATE fk_notpartitioned_pk SET b = 2504 WHERE a = 2500;
 -- check psql behavior
 \d fk_notpartitioned_pk
 
--- Check the exsting FK trigger
+-- Check the existing FK trigger
 SELECT conname, tgrelid::regclass as tgrel, regexp_replace(tgname, '[0-9]+', 'N') as tgname, tgtype
 FROM pg_trigger t JOIN pg_constraint c ON (t.tgconstraint = c.oid)
 WHERE tgrelid IN (SELECT relid FROM pg_partition_tree('fk_partitioned_fk'::regclass)
diff --git a/src/test/regress/sql/generated_stored.sql b/src/test/regress/sql/generated_stored.sql
index 4ec155f2da989..f56fde8d4e5d0 100644
--- a/src/test/regress/sql/generated_stored.sql
+++ b/src/test/regress/sql/generated_stored.sql
@@ -595,6 +595,19 @@ ALTER TABLE gtest30_1 ALTER COLUMN b DROP EXPRESSION;  -- error
 CREATE TABLE gtest31_1 (a int, b text GENERATED ALWAYS AS ('hello') STORED, c text);
 CREATE TABLE gtest31_2 (x int, y gtest31_1);
 ALTER TABLE gtest31_1 ALTER COLUMN b TYPE varchar;  -- fails
+
+-- bug #18970: these cases are unsupported, but make sure they fail cleanly
+ALTER TABLE gtest31_2 ADD CONSTRAINT cc CHECK ((y).b IS NOT NULL);
+ALTER TABLE gtest31_1 ALTER COLUMN b SET EXPRESSION AS ('hello1');
+ALTER TABLE gtest31_2 DROP CONSTRAINT cc;
+
+CREATE STATISTICS gtest31_2_stat ON ((y).b is not null) FROM gtest31_2;
+ALTER TABLE gtest31_1 ALTER COLUMN b SET EXPRESSION AS ('hello2');
+DROP STATISTICS gtest31_2_stat;
+
+CREATE INDEX gtest31_2_y_idx ON gtest31_2(((y).b));
+ALTER TABLE gtest31_1 ALTER COLUMN b SET EXPRESSION AS ('hello3');
+
 DROP TABLE gtest31_1, gtest31_2;
 
 -- Check it for a partitioned table, too
diff --git a/src/test/regress/sql/generated_virtual.sql b/src/test/regress/sql/generated_virtual.sql
index 6fa986515b9e3..ba19bc4c701e0 100644
--- a/src/test/regress/sql/generated_virtual.sql
+++ b/src/test/regress/sql/generated_virtual.sql
@@ -646,6 +646,19 @@ ALTER TABLE gtest30_1 ALTER COLUMN b DROP EXPRESSION;  -- error
 CREATE TABLE gtest31_1 (a int, b text GENERATED ALWAYS AS ('hello') VIRTUAL, c text);
 CREATE TABLE gtest31_2 (x int, y gtest31_1);
 ALTER TABLE gtest31_1 ALTER COLUMN b TYPE varchar;  -- fails
+
+-- bug #18970
+ALTER TABLE gtest31_2 ADD CONSTRAINT cc CHECK ((y).b IS NOT NULL);
+ALTER TABLE gtest31_1 ALTER COLUMN b SET EXPRESSION AS ('hello1');
+ALTER TABLE gtest31_2 DROP CONSTRAINT cc;
+
+CREATE STATISTICS gtest31_2_stat ON ((y).b is not null) FROM gtest31_2;
+ALTER TABLE gtest31_1 ALTER COLUMN b SET EXPRESSION AS ('hello2');
+DROP STATISTICS gtest31_2_stat;
+
+CREATE INDEX gtest31_2_y_idx ON gtest31_2(((y).b));
+ALTER TABLE gtest31_1 ALTER COLUMN b SET EXPRESSION AS ('hello3');
+
 DROP TABLE gtest31_1, gtest31_2;
 
 -- Check it for a partitioned table, too
@@ -845,4 +858,13 @@ select * from gtest32 t group by grouping sets (a, b, c, d, e) having c = 20;
 -- Ensure that the virtual generated columns in ALTER COLUMN TYPE USING expression are expanded
 alter table gtest32 alter column e type bigint using b;
 
+-- Ensure that virtual generated column references within SubLinks that should
+-- be transformed into joins can get expanded
+explain (costs off)
+select 1 from gtest32 t1 where exists
+  (select 1 from gtest32 t2 where t1.a > t2.a and t2.b = 2);
+
+select 1 from gtest32 t1 where exists
+  (select 1 from gtest32 t2 where t1.a > t2.a and t2.b = 2);
+
 drop table gtest32;
diff --git a/src/test/regress/sql/incremental_sort.sql b/src/test/regress/sql/incremental_sort.sql
index f1f8fae56549a..bbe658a7588c9 100644
--- a/src/test/regress/sql/incremental_sort.sql
+++ b/src/test/regress/sql/incremental_sort.sql
@@ -298,3 +298,27 @@ explain (costs off)
 select * from
   (select * from tenk1 order by four) t1 join tenk1 t2 on t1.four = t2.four and t1.two = t2.two
 order by t1.four, t1.two limit 1;
+
+--
+-- Test incremental sort for Append/MergeAppend
+--
+create table prt_tbl (a int, b int) partition by range (a);
+create table prt_tbl_1 partition of prt_tbl for values from (0) to (100);
+create table prt_tbl_2 partition of prt_tbl for values from (100) to (200);
+insert into prt_tbl select i%200, i from generate_series(1,1000)i;
+create index on prt_tbl_1(a);
+create index on prt_tbl_2(a, b);
+analyze prt_tbl;
+
+set enable_seqscan to off;
+set enable_bitmapscan to off;
+
+-- Ensure we get an incremental sort for the subpath of Append
+explain (costs off) select * from prt_tbl order by a, b;
+
+-- Ensure we get an incremental sort for the subpath of MergeAppend
+explain (costs off) select * from prt_tbl_1 union all select * from prt_tbl_2 order by a, b;
+
+reset enable_bitmapscan;
+reset enable_seqscan;
+drop table prt_tbl;
diff --git a/src/test/regress/sql/join.sql b/src/test/regress/sql/join.sql
index f6e7070db656b..5f0a475894ddc 100644
--- a/src/test/regress/sql/join.sql
+++ b/src/test/regress/sql/join.sql
@@ -1977,13 +1977,13 @@ select * from
   (select 1 as id) as xx
   left join
     (tenk1 as a1 full join (select 1 as id) as yy on (a1.unique1 = yy.id))
-  on (xx.id = coalesce(yy.id));
+  on (xx.id = coalesce(yy.id, yy.id));
 
 select * from
   (select 1 as id) as xx
   left join
     (tenk1 as a1 full join (select 1 as id) as yy on (a1.unique1 = yy.id))
-  on (xx.id = coalesce(yy.id));
+  on (xx.id = coalesce(yy.id, yy.id));
 
 --
 -- test ability to push constants through outer join clauses
@@ -3169,9 +3169,9 @@ select * from int4_tbl i left join
   lateral (select * from int2_tbl j where i.f1 = j.f1) k on true;
 explain (verbose, costs off)
 select * from int4_tbl i left join
-  lateral (select coalesce(i) from int2_tbl j where i.f1 = j.f1) k on true;
+  lateral (select coalesce(i, i) from int2_tbl j where i.f1 = j.f1) k on true;
 select * from int4_tbl i left join
-  lateral (select coalesce(i) from int2_tbl j where i.f1 = j.f1) k on true;
+  lateral (select coalesce(i, i) from int2_tbl j where i.f1 = j.f1) k on true;
 explain (verbose, costs off)
 select * from int4_tbl a,
   lateral (
@@ -3637,7 +3637,7 @@ ANALYZE group_tbl;
 
 EXPLAIN (COSTS OFF)
 SELECT 1 FROM group_tbl t1
-    LEFT JOIN (SELECT a c1, COALESCE(a) c2 FROM group_tbl t2) s ON TRUE
+    LEFT JOIN (SELECT a c1, COALESCE(a, a) c2 FROM group_tbl t2) s ON TRUE
 GROUP BY s.c1, s.c2;
 
 DROP TABLE group_tbl;
diff --git a/src/test/regress/sql/memoize.sql b/src/test/regress/sql/memoize.sql
index c0d47fa875ad9..8d1cdd6990c87 100644
--- a/src/test/regress/sql/memoize.sql
+++ b/src/test/regress/sql/memoize.sql
@@ -26,6 +26,7 @@ begin
         ln := regexp_replace(ln, 'Heap Fetches: \d+', 'Heap Fetches: N');
         ln := regexp_replace(ln, 'loops=\d+', 'loops=N');
         ln := regexp_replace(ln, 'Index Searches: \d+', 'Index Searches: N');
+        ln := regexp_replace(ln, 'Memory: \d+kB', 'Memory: NkB');
         return next ln;
     end loop;
 end;
@@ -244,3 +245,29 @@ RESET max_parallel_workers_per_gather;
 RESET parallel_tuple_cost;
 RESET parallel_setup_cost;
 RESET min_parallel_table_scan_size;
+
+-- Ensure memoize works for ANTI joins
+CREATE TABLE tab_anti (a int, b boolean);
+INSERT INTO tab_anti SELECT i%3, false FROM generate_series(1,100)i;
+ANALYZE tab_anti;
+
+-- Ensure we get a Memoize plan for ANTI join
+SELECT explain_memoize('
+SELECT COUNT(*) FROM tab_anti t1 LEFT JOIN
+LATERAL (SELECT DISTINCT ON (a) a, b, t1.a AS x FROM tab_anti t2) t2
+ON t1.a+1 = t2.a
+WHERE t2.a IS NULL;', false);
+
+-- And check we get the expected results.
+SELECT COUNT(*) FROM tab_anti t1 LEFT JOIN
+LATERAL (SELECT DISTINCT ON (a) a, b, t1.a AS x FROM tab_anti t2) t2
+ON t1.a+1 = t2.a
+WHERE t2.a IS NULL;
+
+-- Ensure we do not add memoize node for SEMI join
+EXPLAIN (COSTS OFF)
+SELECT * FROM tab_anti t1 WHERE t1.a IN
+ (SELECT a FROM tab_anti t2 WHERE t2.b IN
+  (SELECT t1.b FROM tab_anti t3 WHERE t2.a > 1 OFFSET 0));
+
+DROP TABLE tab_anti;
diff --git a/src/test/regress/sql/numeric.sql b/src/test/regress/sql/numeric.sql
index b98ae27df5691..640c6d92f4ce7 100644
--- a/src/test/regress/sql/numeric.sql
+++ b/src/test/regress/sql/numeric.sql
@@ -869,6 +869,8 @@ SELECT width_bucket(5.0::float8, 3.0::float8, 4.0::float8, 0);
 SELECT width_bucket(5.0::float8, 3.0::float8, 4.0::float8, -5);
 SELECT width_bucket(3.5::float8, 3.0::float8, 3.0::float8, 888);
 SELECT width_bucket('NaN', 3.0, 4.0, 888);
+SELECT width_bucket('NaN'::float8, 3.0::float8, 4.0::float8, 888);
+SELECT width_bucket(0, 'NaN', 4.0, 888);
 SELECT width_bucket(0::float8, 'NaN', 4.0::float8, 888);
 SELECT width_bucket(2.0, 3.0, '-inf', 888);
 SELECT width_bucket(0::float8, '-inf', 4.0::float8, 888);
diff --git a/src/test/regress/sql/predicate.sql b/src/test/regress/sql/predicate.sql
index 9dcb81b1bc52f..d92277353a019 100644
--- a/src/test/regress/sql/predicate.sql
+++ b/src/test/regress/sql/predicate.sql
@@ -115,6 +115,24 @@ SELECT * FROM pred_tab t1
     LEFT JOIN pred_tab t2 ON t1.a = 1
     LEFT JOIN pred_tab t3 ON t2.a IS NULL OR t2.c IS NULL;
 
+--
+-- Tests for NullTest reduction in EXISTS sublink
+--
+
+-- Ensure the IS_NOT_NULL qual is ignored
+EXPLAIN (COSTS OFF)
+SELECT * FROM pred_tab t1
+    LEFT JOIN pred_tab t2 ON EXISTS
+        (SELECT 1 FROM pred_tab t3, pred_tab t4, pred_tab t5, pred_tab t6
+         WHERE t1.a = t3.a AND t6.a IS NOT NULL);
+
+-- Ensure the IS_NULL qual is reduced to constant-FALSE
+EXPLAIN (COSTS OFF)
+SELECT * FROM pred_tab t1
+    LEFT JOIN pred_tab t2 ON EXISTS
+        (SELECT 1 FROM pred_tab t3, pred_tab t4, pred_tab t5, pred_tab t6
+         WHERE t1.a = t3.a AND t6.a IS NULL);
+
 DROP TABLE pred_tab;
 
 -- Validate we handle IS NULL and IS NOT NULL quals correctly with inheritance
diff --git a/src/test/regress/sql/privileges.sql b/src/test/regress/sql/privileges.sql
index f337aa67c13f2..3eacc1340aad2 100644
--- a/src/test/regress/sql/privileges.sql
+++ b/src/test/regress/sql/privileges.sql
@@ -1544,6 +1544,14 @@ SELECT makeaclitem('regress_priv_user1'::regrole, 'regress_priv_user2'::regrole,
 SELECT makeaclitem('regress_priv_user1'::regrole, 'regress_priv_user2'::regrole,
 	'SELECT, fake_privilege', FALSE);  -- error
 
+-- Test quoting and dequoting of user names in ACLs
+CREATE ROLE "regress_""quoted";
+SELECT makeaclitem('regress_"quoted'::regrole, 'regress_"quoted'::regrole,
+                   'SELECT', TRUE);
+SELECT '"regress_""quoted"=r*/"regress_""quoted"'::aclitem;
+SELECT '""=r*/""'::aclitem;  -- used to be misparsed as """"
+DROP ROLE "regress_""quoted";
+
 -- Test non-throwing aclitem I/O
 SELECT pg_input_is_valid('regress_priv_user1=r/regress_priv_user2', 'aclitem');
 SELECT pg_input_is_valid('regress_priv_user1=r/', 'aclitem');
@@ -1948,7 +1956,8 @@ DROP TABLE lock_table;
 DROP USER regress_locktable_user;
 
 -- test to check privileges of system views pg_shmem_allocations,
--- pg_shmem_allocations_numa and pg_backend_memory_contexts.
+-- pg_shmem_allocations_numa, pg_dsm_registry_allocations, and
+-- pg_backend_memory_contexts.
 
 -- switch to superuser
 \c -
@@ -1959,6 +1968,7 @@ SELECT has_table_privilege('regress_readallstats','pg_aios','SELECT'); -- no
 SELECT has_table_privilege('regress_readallstats','pg_backend_memory_contexts','SELECT'); -- no
 SELECT has_table_privilege('regress_readallstats','pg_shmem_allocations','SELECT'); -- no
 SELECT has_table_privilege('regress_readallstats','pg_shmem_allocations_numa','SELECT'); -- no
+SELECT has_table_privilege('regress_readallstats','pg_dsm_registry_allocations','SELECT'); -- no
 
 GRANT pg_read_all_stats TO regress_readallstats;
 
@@ -1966,6 +1976,7 @@ SELECT has_table_privilege('regress_readallstats','pg_aios','SELECT'); -- yes
 SELECT has_table_privilege('regress_readallstats','pg_backend_memory_contexts','SELECT'); -- yes
 SELECT has_table_privilege('regress_readallstats','pg_shmem_allocations','SELECT'); -- yes
 SELECT has_table_privilege('regress_readallstats','pg_shmem_allocations_numa','SELECT'); -- yes
+SELECT has_table_privilege('regress_readallstats','pg_dsm_registry_allocations','SELECT'); -- yes
 
 -- run query to ensure that functions within views can be executed
 SET ROLE regress_readallstats;
diff --git a/src/test/regress/sql/publication.sql b/src/test/regress/sql/publication.sql
index c9e309190dfa6..deddf0da8445f 100644
--- a/src/test/regress/sql/publication.sql
+++ b/src/test/regress/sql/publication.sql
@@ -26,6 +26,7 @@ CREATE PUBLICATION testpub_xxx WITH (publish = 'cluster, vacuum');
 CREATE PUBLICATION testpub_xxx WITH (publish_via_partition_root = 'true', publish_via_partition_root = '0');
 CREATE PUBLICATION testpub_xxx WITH (publish_generated_columns = stored, publish_generated_columns = none);
 CREATE PUBLICATION testpub_xxx WITH (publish_generated_columns = foo);
+CREATE PUBLICATION testpub_xxx WITH (publish_generated_columns);
 
 \dRp
 
@@ -1183,19 +1184,15 @@ DROP SCHEMA sch2 cascade;
 -- ======================================================
 
 -- Test the 'publish_generated_columns' parameter with the following values:
--- 'stored', 'none', and the default (no value specified), which defaults to
--- 'stored'.
+-- 'stored', 'none'.
 SET client_min_messages = 'ERROR';
 CREATE PUBLICATION pub1 FOR ALL TABLES WITH (publish_generated_columns = stored);
 \dRp+ pub1
 CREATE PUBLICATION pub2 FOR ALL TABLES WITH (publish_generated_columns = none);
 \dRp+ pub2
-CREATE PUBLICATION pub3 FOR ALL TABLES WITH (publish_generated_columns);
-\dRp+ pub3
 
 DROP PUBLICATION pub1;
 DROP PUBLICATION pub2;
-DROP PUBLICATION pub3;
 
 -- Test the 'publish_generated_columns' parameter as 'none' and 'stored' for
 -- different scenarios with/without generated columns in column lists.
@@ -1229,3 +1226,25 @@ RESET client_min_messages;
 RESET SESSION AUTHORIZATION;
 DROP ROLE regress_publication_user, regress_publication_user2;
 DROP ROLE regress_publication_user_dummy;
+
+-- stage objects for pg_dump tests
+CREATE SCHEMA pubme CREATE TABLE t0 (c int, d int) CREATE TABLE t1 (c int);
+CREATE SCHEMA pubme2 CREATE TABLE t0 (c int, d int);
+SET client_min_messages = 'ERROR';
+CREATE PUBLICATION dump_pub_qual_1ct FOR
+  TABLE ONLY pubme.t0 (c, d) WHERE (c > 0);
+CREATE PUBLICATION dump_pub_qual_2ct FOR
+  TABLE ONLY pubme.t0 (c) WHERE (c > 0),
+  TABLE ONLY pubme.t1 (c);
+CREATE PUBLICATION dump_pub_nsp_1ct FOR
+  TABLES IN SCHEMA pubme;
+CREATE PUBLICATION dump_pub_nsp_2ct FOR
+  TABLES IN SCHEMA pubme,
+  TABLES IN SCHEMA pubme2;
+CREATE PUBLICATION dump_pub_all FOR
+  TABLE ONLY pubme.t0,
+  TABLE ONLY pubme.t1 WHERE (c < 0),
+  TABLES IN SCHEMA pubme,
+  TABLES IN SCHEMA pubme2
+  WITH (publish_via_partition_root = true);
+RESET client_min_messages;
diff --git a/src/test/regress/sql/regproc.sql b/src/test/regress/sql/regproc.sql
index 232289ac39823..cfec8f8c754a2 100644
--- a/src/test/regress/sql/regproc.sql
+++ b/src/test/regress/sql/regproc.sql
@@ -47,11 +47,42 @@ SELECT regrole('regress_regrole_test');
 SELECT regrole('"regress_regrole_test"');
 SELECT regnamespace('pg_catalog');
 SELECT regnamespace('"pg_catalog"');
+SELECT regdatabase('template1');
+SELECT regdatabase('"template1"');
 
 SELECT to_regrole('regress_regrole_test');
 SELECT to_regrole('"regress_regrole_test"');
 SELECT to_regnamespace('pg_catalog');
 SELECT to_regnamespace('"pg_catalog"');
+SELECT to_regdatabase('template1');
+SELECT to_regdatabase('"template1"');
+
+-- special "single dash" case
+
+SELECT regproc('-')::oid;
+SELECT regprocedure('-')::oid;
+SELECT regclass('-')::oid;
+SELECT regcollation('-')::oid;
+SELECT regtype('-')::oid;
+SELECT regconfig('-')::oid;
+SELECT regdictionary('-')::oid;
+SELECT regrole('-')::oid;
+SELECT regnamespace('-')::oid;
+SELECT regdatabase('-')::oid;
+
+SELECT to_regproc('-')::oid;
+SELECT to_regprocedure('-')::oid;
+SELECT to_regclass('-')::oid;
+SELECT to_regcollation('-')::oid;
+SELECT to_regtype('-')::oid;
+SELECT to_regrole('-')::oid;
+SELECT to_regnamespace('-')::oid;
+SELECT to_regdatabase('-')::oid;
+
+-- constant cannot be used here
+
+CREATE TABLE regrole_test (rolid OID DEFAULT 'regress_regrole_test'::regrole);
+CREATE TABLE regdatabase_test (datid OID DEFAULT 'template1'::regdatabase);
 
 /* If objects don't exist, raise errors. */
 
@@ -88,6 +119,9 @@ SELECT regrole('foo.bar');
 SELECT regnamespace('Nonexistent');
 SELECT regnamespace('"Nonexistent"');
 SELECT regnamespace('foo.bar');
+SELECT regdatabase('Nonexistent');
+SELECT regdatabase('"Nonexistent"');
+SELECT regdatabase('foo.bar');
 
 /* If objects don't exist, return NULL with no error. */
 
@@ -122,6 +156,9 @@ SELECT to_regrole('foo.bar');
 SELECT to_regnamespace('Nonexistent');
 SELECT to_regnamespace('"Nonexistent"');
 SELECT to_regnamespace('foo.bar');
+SELECT to_regdatabase('Nonexistent');
+SELECT to_regdatabase('"Nonexistent"');
+SELECT to_regdatabase('foo.bar');
 
 -- Test to_regtypemod
 SELECT to_regtypemod('text');
@@ -147,6 +184,7 @@ SELECT * FROM pg_input_error_info('ng_catalog.abs(numeric)', 'regprocedure');
 SELECT * FROM pg_input_error_info('ng_catalog.abs(numeric', 'regprocedure');
 SELECT * FROM pg_input_error_info('regress_regrole_test', 'regrole');
 SELECT * FROM pg_input_error_info('no_such_type', 'regtype');
+SELECT * FROM pg_input_error_info('Nonexistent', 'regdatabase');
 
 -- Some cases that should be soft errors, but are not yet
 SELECT * FROM pg_input_error_info('incorrect type name syntax', 'regtype');
diff --git a/src/test/regress/sql/stats.sql b/src/test/regress/sql/stats.sql
index 232ab8db8fa8b..54e7286634452 100644
--- a/src/test/regress/sql/stats.sql
+++ b/src/test/regress/sql/stats.sql
@@ -439,8 +439,13 @@ DROP TABLE test_stats_temp;
 -- Checkpoint twice: The checkpointer reports stats after reporting completion
 -- of the checkpoint. But after a second checkpoint we'll see at least the
 -- results of the first.
-CHECKPOINT;
-CHECKPOINT;
+--
+-- While at it, test checkpoint options.  Note that we don't test MODE SPREAD
+-- because it would prolong the test.
+CHECKPOINT (WRONG);
+CHECKPOINT (MODE WRONG);
+CHECKPOINT (MODE FAST, FLUSH_UNLOGGED FALSE);
+CHECKPOINT (FLUSH_UNLOGGED);
 
 SELECT num_requested > :rqst_ckpts_before FROM pg_stat_checkpointer;
 SELECT wal_bytes > :wal_bytes_before FROM pg_stat_wal;
diff --git a/src/test/regress/sql/strings.sql b/src/test/regress/sql/strings.sql
index 2577a42987de7..92c445c243961 100644
--- a/src/test/regress/sql/strings.sql
+++ b/src/test/regress/sql/strings.sql
@@ -76,6 +76,7 @@ SELECT E'De\\000dBeEf'::bytea;
 SELECT E'De\123dBeEf'::bytea;
 SELECT E'De\\123dBeEf'::bytea;
 SELECT E'De\\678dBeEf'::bytea;
+SELECT E'DeAd\\\\BeEf'::bytea;
 
 SELECT reverse(''::bytea);
 SELECT reverse('\xaa'::bytea);
@@ -88,6 +89,7 @@ SELECT E'\\xDe00BeEf'::bytea;
 SELECT E'DeAdBeEf'::bytea;
 SELECT E'De\\000dBeEf'::bytea;
 SELECT E'De\\123dBeEf'::bytea;
+SELECT E'DeAd\\\\BeEf'::bytea;
 
 -- Test non-error-throwing API too
 SELECT pg_input_is_valid(E'\\xDeAdBeE', 'bytea');
diff --git a/src/test/regress/sql/subscription.sql b/src/test/regress/sql/subscription.sql
index 007c9e7037463..f0f714fe747a9 100644
--- a/src/test/regress/sql/subscription.sql
+++ b/src/test/regress/sql/subscription.sql
@@ -287,6 +287,17 @@ ALTER SUBSCRIPTION regress_testsub SET (disable_on_error = true);
 ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
 DROP SUBSCRIPTION regress_testsub;
 
+-- fail - retain_dead_tuples must be boolean
+CREATE SUBSCRIPTION regress_testsub CONNECTION 'dbname=regress_doesnotexist' PUBLICATION testpub WITH (connect = false, retain_dead_tuples = foo);
+
+-- ok
+CREATE SUBSCRIPTION regress_testsub CONNECTION 'dbname=regress_doesnotexist' PUBLICATION testpub WITH (connect = false, retain_dead_tuples = false);
+
+\dRs+
+
+ALTER SUBSCRIPTION regress_testsub SET (slot_name = NONE);
+DROP SUBSCRIPTION regress_testsub;
+
 -- let's do some tests with pg_create_subscription rather than superuser
 SET SESSION AUTHORIZATION regress_subscription_user3;
 
diff --git a/src/test/regress/sql/subselect.sql b/src/test/regress/sql/subselect.sql
index fec38ef85a6a6..d9a841fbc9ffd 100644
--- a/src/test/regress/sql/subselect.sql
+++ b/src/test/regress/sql/subselect.sql
@@ -1041,7 +1041,7 @@ explain (verbose, costs off)
 select ss2.* from
   int8_tbl t1 left join
   (int8_tbl t2 left join
-   (select coalesce(q1) as x, * from int8_tbl t3) ss1 on t2.q1 = ss1.q2 inner join
+   (select coalesce(q1, q1) as x, * from int8_tbl t3) ss1 on t2.q1 = ss1.q2 inner join
    lateral (select ss1.x as y, * from int8_tbl t4) ss2 on t2.q2 = ss2.q1)
   on t1.q2 = ss2.q1
 order by 1, 2, 3;
@@ -1049,7 +1049,7 @@ order by 1, 2, 3;
 select ss2.* from
   int8_tbl t1 left join
   (int8_tbl t2 left join
-   (select coalesce(q1) as x, * from int8_tbl t3) ss1 on t2.q1 = ss1.q2 inner join
+   (select coalesce(q1, q1) as x, * from int8_tbl t3) ss1 on t2.q1 = ss1.q2 inner join
    lateral (select ss1.x as y, * from int8_tbl t4) ss2 on t2.q2 = ss2.q1)
   on t1.q2 = ss2.q1
 order by 1, 2, 3;
@@ -1059,7 +1059,7 @@ explain (verbose, costs off)
 select ss2.* from
   int8_tbl t1 left join
   (int8_tbl t2 left join
-   (select coalesce(q1) as x, * from int8_tbl t3) ss1 on t2.q1 = ss1.q2 left join
+   (select coalesce(q1, q1) as x, * from int8_tbl t3) ss1 on t2.q1 = ss1.q2 left join
    lateral (select ss1.x as y, * from int8_tbl t4) ss2 on t2.q2 = ss2.q1)
   on t1.q2 = ss2.q1
 order by 1, 2, 3;
@@ -1067,7 +1067,7 @@ order by 1, 2, 3;
 select ss2.* from
   int8_tbl t1 left join
   (int8_tbl t2 left join
-   (select coalesce(q1) as x, * from int8_tbl t3) ss1 on t2.q1 = ss1.q2 left join
+   (select coalesce(q1, q1) as x, * from int8_tbl t3) ss1 on t2.q1 = ss1.q2 left join
    lateral (select ss1.x as y, * from int8_tbl t4) ss2 on t2.q2 = ss2.q1)
   on t1.q2 = ss2.q1
 order by 1, 2, 3;
diff --git a/src/test/regress/sql/triggers.sql b/src/test/regress/sql/triggers.sql
index 9ffd318385ff6..d674b25c83be4 100644
--- a/src/test/regress/sql/triggers.sql
+++ b/src/test/regress/sql/triggers.sql
@@ -1576,6 +1576,19 @@ select * from parted;
 drop table parted;
 drop function parted_trigfunc();
 
+--
+-- Constraint triggers
+--
+create constraint trigger crtr
+  after insert on foo not valid
+  for each row execute procedure foo ();
+create constraint trigger crtr
+  after insert on foo no inherit
+  for each row execute procedure foo ();
+create constraint trigger crtr
+  after insert on foo not enforced
+  for each row execute procedure foo ();
+
 --
 -- Constraint triggers and partitioned tables
 create table parted_constr_ancestor (a int, b text)
@@ -1591,7 +1604,7 @@ create constraint trigger parted_trig after insert on parted_constr_ancestor
   deferrable
   for each row execute procedure trigger_notice_ab();
 create constraint trigger parted_trig_two after insert on parted_constr
-  deferrable initially deferred
+  deferrable initially deferred enforced
   for each row when (bark(new.b) AND new.a % 2 = 1)
   execute procedure trigger_notice_ab();
 
diff --git a/src/test/regress/sql/type_sanity.sql b/src/test/regress/sql/type_sanity.sql
index c94dd83d3061c..df795759bb4cb 100644
--- a/src/test/regress/sql/type_sanity.sql
+++ b/src/test/regress/sql/type_sanity.sql
@@ -539,6 +539,7 @@ CREATE TABLE tab_core_types AS SELECT
   'regtype'::regtype type,
   'pg_monitor'::regrole,
   'pg_class'::regclass::oid,
+  'template1'::regdatabase,
   '(1,1)'::tid, '2'::xid, '3'::cid,
   '10:20:10,14,15'::txid_snapshot,
   '10:20:10,14,15'::pg_snapshot,
diff --git a/src/test/ssl/meson.build b/src/test/ssl/meson.build
index cf8b2b9303a0c..d8e0fb518e0a2 100644
--- a/src/test/ssl/meson.build
+++ b/src/test/ssl/meson.build
@@ -7,7 +7,7 @@ tests += {
   'tap': {
     'env': {
       'with_ssl': ssl_library,
-      'OPENSSL': openssl.found() ? openssl.path() : '',
+      'OPENSSL': openssl.found() ? openssl.full_path() : '',
     },
     'tests': [
       't/001_ssltests.pl',
diff --git a/src/test/ssl/t/001_ssltests.pl b/src/test/ssl/t/001_ssltests.pl
index 2cb4d0ffd4199..b2eb18d3e815e 100644
--- a/src/test/ssl/t/001_ssltests.pl
+++ b/src/test/ssl/t/001_ssltests.pl
@@ -173,6 +173,13 @@ sub switch_server_cert
 	ok( (@status = stat("$tempdir/key.txt")),
 		"keylog file exists and returned status");
 	ok(@status && !($status[2] & 0006), "keylog file is not world readable");
+
+	# Connect should work with an incorrect sslkeylogfile, with the error to
+	# open the logfile printed to stderr
+	$node->connect_ok(
+		"$common_connstr sslrootcert=ssl/root+server_ca.crt sslkeylogfile=$tempdir/invalid/key.txt sslmode=require",
+		"connect with server root cert and incorrect sslkeylogfile path",
+		expected_stderr => qr/could not open/);
 }
 
 # The server should not accept non-SSL connections.
diff --git a/src/test/subscription/t/035_conflicts.pl b/src/test/subscription/t/035_conflicts.pl
index d78a6bac16aeb..36aeb14c563af 100644
--- a/src/test/subscription/t/035_conflicts.pl
+++ b/src/test/subscription/t/035_conflicts.pl
@@ -1,6 +1,6 @@
 # Copyright (c) 2025, PostgreSQL Global Development Group
 
-# Test the conflict detection of conflict type 'multiple_unique_conflicts'.
+# Test conflicts in logical replication
 use strict;
 use warnings FATAL => 'all';
 use PostgreSQL::Test::Cluster;
@@ -18,7 +18,7 @@
 
 # Create a subscriber node
 my $node_subscriber = PostgreSQL::Test::Cluster->new('subscriber');
-$node_subscriber->init;
+$node_subscriber->init(allows_streaming => 'logical');
 $node_subscriber->start;
 
 # Create a table on publisher
@@ -146,4 +146,267 @@
 
 pass('multiple_unique_conflicts detected on a leaf partition during insert');
 
+###############################################################################
+# Setup a bidirectional logical replication between node_A & node_B
+###############################################################################
+
+# Initialize nodes. Enable the track_commit_timestamp on both nodes to detect
+# the conflict when attempting to update a row that was previously modified by
+# a different origin.
+
+# node_A. Increase the log_min_messages setting to DEBUG2 to debug test
+# failures. Disable autovacuum to avoid generating xid that could affect the
+# replication slot's xmin value.
+my $node_A = $node_publisher;
+$node_A->append_conf(
+	'postgresql.conf',
+	qq{track_commit_timestamp = on
+	autovacuum = off
+	log_min_messages = 'debug2'});
+$node_A->restart;
+
+# node_B
+my $node_B = $node_subscriber;
+$node_B->append_conf('postgresql.conf', "track_commit_timestamp = on");
+$node_B->restart;
+
+# Create table on node_A
+$node_A->safe_psql('postgres', "CREATE TABLE tab (a int PRIMARY KEY, b int)");
+
+# Create the same table on node_B
+$node_B->safe_psql('postgres', "CREATE TABLE tab (a int PRIMARY KEY, b int)");
+
+my $subname_AB = 'tap_sub_a_b';
+my $subname_BA = 'tap_sub_b_a';
+
+# Setup logical replication
+# node_A (pub) -> node_B (sub)
+my $node_A_connstr = $node_A->connstr . ' dbname=postgres';
+$node_A->safe_psql('postgres', "CREATE PUBLICATION tap_pub_A FOR TABLE tab");
+$node_B->safe_psql(
+	'postgres', "
+	CREATE SUBSCRIPTION $subname_BA
+	CONNECTION '$node_A_connstr application_name=$subname_BA'
+	PUBLICATION tap_pub_A
+	WITH (origin = none, retain_dead_tuples = true)");
+
+# node_B (pub) -> node_A (sub)
+my $node_B_connstr = $node_B->connstr . ' dbname=postgres';
+$node_B->safe_psql('postgres', "CREATE PUBLICATION tap_pub_B FOR TABLE tab");
+$node_A->safe_psql(
+	'postgres', "
+	CREATE SUBSCRIPTION $subname_AB
+	CONNECTION '$node_B_connstr application_name=$subname_AB'
+	PUBLICATION tap_pub_B
+	WITH (origin = none, copy_data = off)");
+
+# Wait for initial table sync to finish
+$node_A->wait_for_subscription_sync($node_B, $subname_AB);
+$node_B->wait_for_subscription_sync($node_A, $subname_BA);
+
+is(1, 1, 'Bidirectional replication setup is complete');
+
+# Confirm that the conflict detection slot is created on Node B and the xmin
+# value is valid.
+ok( $node_B->poll_query_until(
+		'postgres',
+		"SELECT xmin IS NOT NULL from pg_replication_slots WHERE slot_name = 'pg_conflict_detection'"
+	),
+	"the xmin value of slot 'pg_conflict_detection' is valid on Node B");
+
+##################################################
+# Check that the retain_dead_tuples option can be enabled only for disabled
+# subscriptions. Validate the NOTICE message during the subscription DDL, and
+# ensure the conflict detection slot is created upon enabling the
+# retain_dead_tuples option.
+##################################################
+
+# Alter retain_dead_tuples for enabled subscription
+my ($cmdret, $stdout, $stderr) = $node_A->psql('postgres',
+	"ALTER SUBSCRIPTION $subname_AB SET (retain_dead_tuples = true)");
+ok( $stderr =~
+	  /ERROR:  cannot set option \"retain_dead_tuples\" for enabled subscription/,
+	"altering retain_dead_tuples is not allowed for enabled subscription");
+
+# Disable the subscription
+$node_A->psql('postgres', "ALTER SUBSCRIPTION $subname_AB DISABLE;");
+
+# Wait for the apply worker to stop
+$node_A->poll_query_until('postgres',
+	"SELECT count(*) = 0 FROM pg_stat_activity WHERE backend_type = 'logical replication apply worker'"
+);
+
+# Enable retain_dead_tuples for disabled subscription
+($cmdret, $stdout, $stderr) = $node_A->psql('postgres',
+	"ALTER SUBSCRIPTION $subname_AB SET (retain_dead_tuples = true);");
+ok( $stderr =~
+	  /NOTICE:  deleted rows to detect conflicts would not be removed until the subscription is enabled/,
+	"altering retain_dead_tuples is allowed for disabled subscription");
+
+# Re-enable the subscription
+$node_A->safe_psql('postgres', "ALTER SUBSCRIPTION $subname_AB ENABLE;");
+
+# Confirm that the conflict detection slot is created on Node A and the xmin
+# value is valid.
+ok( $node_A->poll_query_until(
+		'postgres',
+		"SELECT xmin IS NOT NULL from pg_replication_slots WHERE slot_name = 'pg_conflict_detection'"
+	),
+	"the xmin value of slot 'pg_conflict_detection' is valid on Node A");
+
+##################################################
+# Check the WARNING when changing the origin to ANY, if retain_dead_tuples is
+# enabled. This warns of the possibility of receiving changes from origins
+# other than the publisher.
+##################################################
+
+($cmdret, $stdout, $stderr) = $node_A->psql('postgres',
+	"ALTER SUBSCRIPTION $subname_AB SET (origin = any);");
+ok( $stderr =~
+	  /WARNING:  subscription "tap_sub_a_b" enabled retain_dead_tuples but might not reliably detect conflicts for changes from different origins/,
+	"warn of the possibility of receiving changes from origins other than the publisher");
+
+# Reset the origin to none
+$node_A->psql('postgres',
+	"ALTER SUBSCRIPTION $subname_AB SET (origin = none);");
+
+###############################################################################
+# Check that dead tuples on node A cannot be cleaned by VACUUM until the
+# concurrent transactions on Node B have been applied and flushed on Node A.
+# Also, check that an update_deleted conflict is detected when updating a row
+# that was deleted by a different origin.
+###############################################################################
+
+# Insert a record
+$node_A->safe_psql('postgres', "INSERT INTO tab VALUES (1, 1), (2, 2);");
+$node_A->wait_for_catchup($subname_BA);
+
+my $result = $node_B->safe_psql('postgres', "SELECT * FROM tab;");
+is($result, qq(1|1
+2|2), 'check replicated insert on node B');
+
+# Disable the logical replication from node B to node A
+$node_A->safe_psql('postgres', "ALTER SUBSCRIPTION $subname_AB DISABLE");
+
+# Wait for the apply worker to stop
+$node_A->poll_query_until('postgres',
+	"SELECT count(*) = 0 FROM pg_stat_activity WHERE backend_type = 'logical replication apply worker'"
+);
+
+my $log_location = -s $node_B->logfile;
+
+$node_B->safe_psql('postgres', "UPDATE tab SET b = 3 WHERE a = 1;");
+$node_A->safe_psql('postgres', "DELETE FROM tab WHERE a = 1;");
+
+($cmdret, $stdout, $stderr) = $node_A->psql(
+	'postgres', qq(VACUUM (verbose) public.tab;)
+);
+
+ok( $stderr =~
+	  qr/1 are dead but not yet removable/,
+	'the deleted column is non-removable');
+
+# Ensure the DELETE is replayed on Node B
+$node_A->wait_for_catchup($subname_BA);
+
+# Check the conflict detected on Node B
+my $logfile = slurp_file($node_B->logfile(), $log_location);
+ok( $logfile =~
+	  qr/conflict detected on relation "public.tab": conflict=delete_origin_differs.*
+.*DETAIL:.* Deleting the row that was modified locally in transaction [0-9]+ at .*
+.*Existing local tuple \(1, 3\); replica identity \(a\)=\(1\)/,
+	'delete target row was modified in tab');
+
+$log_location = -s $node_A->logfile;
+
+$node_A->safe_psql(
+	'postgres', "ALTER SUBSCRIPTION $subname_AB ENABLE;");
+$node_B->wait_for_catchup($subname_AB);
+
+$logfile = slurp_file($node_A->logfile(), $log_location);
+ok( $logfile =~
+	  qr/conflict detected on relation "public.tab": conflict=update_deleted.*
+.*DETAIL:.* The row to be updated was deleted locally in transaction [0-9]+ at .*
+.*Remote tuple \(1, 3\); replica identity \(a\)=\(1\)/,
+	'update target row was deleted in tab');
+
+# Remember the next transaction ID to be assigned
+my $next_xid = $node_A->safe_psql('postgres', "SELECT txid_current() + 1;");
+
+# Confirm that the xmin value is advanced to the latest nextXid. If no
+# transactions are running, the apply worker selects nextXid as the candidate
+# for the non-removable xid. See GetOldestActiveTransactionId().
+ok( $node_A->poll_query_until(
+		'postgres',
+		"SELECT xmin = $next_xid from pg_replication_slots WHERE slot_name = 'pg_conflict_detection'"
+	),
+	"the xmin value of slot 'pg_conflict_detection' is updated on Node A");
+
+# Confirm that the dead tuple can be removed now
+($cmdret, $stdout, $stderr) = $node_A->psql(
+	'postgres', qq(VACUUM (verbose) public.tab;)
+);
+
+ok( $stderr =~
+	  qr/1 removed, 1 remain, 0 are dead but not yet removable/,
+	'the deleted column is removed');
+
+###############################################################################
+# Ensure that the deleted tuple needed to detect an update_deleted conflict is
+# accessible via a sequential table scan.
+###############################################################################
+
+# Drop the primary key from tab on node A and set REPLICA IDENTITY to FULL to
+# enforce sequential scanning of the table.
+$node_A->safe_psql('postgres', "ALTER TABLE tab REPLICA IDENTITY FULL");
+$node_B->safe_psql('postgres', "ALTER TABLE tab REPLICA IDENTITY FULL");
+$node_A->safe_psql('postgres', "ALTER TABLE tab DROP CONSTRAINT tab_pkey;");
+
+# Disable the logical replication from node B to node A
+$node_A->safe_psql('postgres', "ALTER SUBSCRIPTION $subname_AB DISABLE");
+
+# Wait for the apply worker to stop
+$node_A->poll_query_until('postgres',
+	"SELECT count(*) = 0 FROM pg_stat_activity WHERE backend_type = 'logical replication apply worker'"
+);
+
+$node_B->safe_psql('postgres', "UPDATE tab SET b = 4 WHERE a = 2;");
+$node_A->safe_psql('postgres', "DELETE FROM tab WHERE a = 2;");
+
+$log_location = -s $node_A->logfile;
+
+$node_A->safe_psql(
+	'postgres', "ALTER SUBSCRIPTION $subname_AB ENABLE;");
+$node_B->wait_for_catchup($subname_AB);
+
+$logfile = slurp_file($node_A->logfile(), $log_location);
+ok( $logfile =~
+	  qr/conflict detected on relation "public.tab": conflict=update_deleted.*
+.*DETAIL:.* The row to be updated was deleted locally in transaction [0-9]+ at .*
+.*Remote tuple \(2, 4\); replica identity full \(2, 2\)/,
+	'update target row was deleted in tab');
+
+###############################################################################
+# Check that the replication slot pg_conflict_detection is dropped after
+# removing all the subscriptions.
+###############################################################################
+
+$node_B->safe_psql(
+	'postgres', "DROP SUBSCRIPTION $subname_BA");
+
+ok( $node_B->poll_query_until(
+		'postgres',
+		"SELECT count(*) = 0 FROM pg_replication_slots WHERE slot_name = 'pg_conflict_detection'"
+	),
+	"the slot 'pg_conflict_detection' has been dropped on Node B");
+
+$node_A->safe_psql(
+	'postgres', "DROP SUBSCRIPTION $subname_AB");
+
+ok( $node_A->poll_query_until(
+		'postgres',
+		"SELECT count(*) = 0 FROM pg_replication_slots WHERE slot_name = 'pg_conflict_detection'"
+	),
+	"the slot 'pg_conflict_detection' has been dropped on Node A");
+
 done_testing();
diff --git a/src/tools/git_changelog b/src/tools/git_changelog
index dccf938685a3a..c25e399a87f5d 100755
--- a/src/tools/git_changelog
+++ b/src/tools/git_changelog
@@ -59,7 +59,7 @@ require IPC::Open2;
 # (We could get this from "git branches", but not worth the trouble.)
 # NB: master must be first!
 my @BRANCHES = qw(master
-  REL_18_STABLE 
+  REL_18_STABLE
   REL_17_STABLE REL_16_STABLE REL_15_STABLE REL_14_STABLE REL_13_STABLE
   REL_12_STABLE REL_11_STABLE REL_10_STABLE REL9_6_STABLE REL9_5_STABLE
   REL9_4_STABLE REL9_3_STABLE REL9_2_STABLE REL9_1_STABLE REL9_0_STABLE
diff --git a/src/tools/pgflex b/src/tools/pgflex
index 3986b06874e75..b8d9aa0086fbb 100755
--- a/src/tools/pgflex
+++ b/src/tools/pgflex
@@ -48,7 +48,7 @@ os.chdir(args.privatedir)
 # contents. Set FLEX_TMP_DIR to the target private directory to avoid
 # that. That environment variable isn't consulted on other platforms, so we
 # don't even need to make this conditional.
-env = {'FLEX_TMP_DIR': args.privatedir}
+os.environ['FLEX_TMP_DIR'] = args.privatedir
 
 # build flex invocation
 command = [args.flex, '-o', args.output_file]
@@ -58,7 +58,7 @@ command += args.flex_flags
 command += [args.input_file]
 
 # create .c file from .l file
-sp = subprocess.run(command, env=env)
+sp = subprocess.run(command)
 if sp.returncode != 0:
     sys.exit(sp.returncode)
 
diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list
index 32d6e718adca0..e6f2e93b2d6fa 100644
--- a/src/tools/pgindent/typedefs.list
+++ b/src/tools/pgindent/typedefs.list
@@ -55,9 +55,6 @@ AggStrategy
 AggTransInfo
 Aggref
 AggregateInstrumentation
-AioWorkerControl
-AioWorkerSlot
-AioWorkerSubmissionQueue
 AlenState
 Alias
 AllocBlock
@@ -74,6 +71,7 @@ AlterDatabaseSetStmt
 AlterDatabaseStmt
 AlterDefaultPrivilegesStmt
 AlterDomainStmt
+AlterDomainType
 AlterEnumStmt
 AlterEventTrigStmt
 AlterExtensionContentsStmt
@@ -521,7 +519,6 @@ CopyFormatOptions
 CopyFromRoutine
 CopyFromState
 CopyFromStateData
-CopyHeaderChoice
 CopyInsertMethod
 CopyLogVerbosityChoice
 CopyMethod
@@ -601,6 +598,7 @@ DR_intorel
 DR_printtup
 DR_sqlfunction
 DR_transientrel
+DSMREntryType
 DSMRegistryCtxStruct
 DSMRegistryEntry
 DWORD
@@ -805,6 +803,7 @@ FastPathStrongRelationLockData
 FdwInfo
 FdwRoutine
 FetchDirection
+FetchDirectionKeywords
 FetchStmt
 FieldSelect
 FieldStore
@@ -1289,6 +1288,7 @@ InjectionPointCacheEntry
 InjectionPointCallback
 InjectionPointCondition
 InjectionPointConditionType
+InjectionPointData
 InjectionPointEntry
 InjectionPointSharedState
 InjectionPointsCtl
@@ -1736,6 +1736,9 @@ Name
 NameData
 NameHashEntry
 NamedArgExpr
+NamedDSAState
+NamedDSHState
+NamedDSMState
 NamedLWLockTranche
 NamedLWLockTrancheRequest
 NamedTuplestoreScan
@@ -1756,6 +1759,7 @@ NonEmptyRange
 Notification
 NotificationList
 NotifyStmt
+NotnullHashEntry
 Nsrt
 NtDllRoutine
 NtFlushBuffersFileEx_t
@@ -1878,7 +1882,6 @@ PGTargetServerType
 PGTernaryBool
 PGTransactionStatusType
 PGVerbosity
-PG_Locale_Strategy
 PG_Lock_Status
 PG_init_t
 PGauthData
@@ -2176,8 +2179,12 @@ PgAioReturn
 PgAioTargetData
 PgAioTargetID
 PgAioTargetInfo
+PgAioUringCaps
 PgAioUringContext
 PgAioWaitRef
+PgAioWorkerControl
+PgAioWorkerSlot
+PgAioWorkerSubmissionQueue
 PgArchData
 PgBackendGSSStatus
 PgBackendSSLStatus
@@ -2268,6 +2275,7 @@ PlanInvalItem
 PlanRowMark
 PlanState
 PlannedStmt
+PlannedStmtOrigin
 PlannerGlobal
 PlannerInfo
 PlannerParamItem
@@ -2559,6 +2567,8 @@ RestrictInfo
 Result
 ResultRelInfo
 ResultState
+RetainDeadTuplesData
+RetainDeadTuplesPhase
 ReturnSetInfo
 ReturnStmt
 ReturningClause
@@ -3006,6 +3016,7 @@ Tcl_Obj
 Tcl_Size
 Tcl_Time
 TempNamespaceStatus
+TestDSMRegistryHashEntry
 TestDSMRegistryStruct
 TestDecodingData
 TestDecodingTxnData
@@ -3475,6 +3486,8 @@ bloom_filter
 boolKEY
 brin_column_state
 brin_serialize_callback_type
+btree_gin_convert_function
+btree_gin_leftmost_function
 bytea
 cached_re_str
 canonicalize_state
@@ -3744,6 +3757,7 @@ leafSegmentInfo
 leaf_item
 libpq_gettext_func
 libpq_source
+libpqsrv_PGresult
 line_t
 lineno_t
 list_sort_comparator
diff --git a/src/tools/valgrind.supp b/src/tools/valgrind.supp
index 7ea464c809417..3880007dfb3bb 100644
--- a/src/tools/valgrind.supp
+++ b/src/tools/valgrind.supp
@@ -180,3 +180,50 @@
    Memcheck:Cond
    fun:PyObject_Realloc
 }
+
+# NUMA introspection requires touching memory first, and some of it may
+# be marked as noacess (e.g. unpinned buffers). So just ignore that.
+{
+   pg_numa_touch_mem_if_required
+   Memcheck:Addr4
+   fun:pg_numa_touch_mem_if_required
+}
+
+{
+   pg_numa_touch_mem_if_required
+   Memcheck:Addr8
+   fun:pg_numa_touch_mem_if_required
+}
+
+
+# Memory-leak suppressions
+# Note that a suppression rule will silence complaints about memory blocks
+# allocated in matching places, but it won't prevent "indirectly lost"
+# complaints about blocks that are only reachable via the suppressed blocks.
+
+# Suppress complaints about stuff leaked during function cache loading.
+# Both the PL/pgSQL and SQL-function parsing processes generate some cruft
+# within the function's cache context, which doesn't seem worth the trouble
+# to get rid of.  Moreover, there are cases where CachedFunction structs
+# are intentionally leaked because we're unsure if any fn_extra pointers
+# remain.
+{
+   hide_function_cache_leaks
+   Memcheck:Leak
+   match-leak-kinds: definite,possible,indirect
+
+   ...
+   fun:cached_function_compile
+}
+
+# Suppress complaints about stuff leaked during TS dictionary loading.
+# Not very much is typically lost there, and preventing it would
+# require a risky API change for TS tmplinit functions.
+{
+   hide_ts_dictionary_leaks
+   Memcheck:Leak
+   match-leak-kinds: definite,possible,indirect
+
+   ...
+   fun:lookup_ts_dictionary_cache
+}

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