Doc: in back branches, don't call it a row constructor if it isn't really.

tglsfdc · tglsfdc · commit 51aebcd78a4a · 2016-11-22T18:07:43.000-05:00
Before commit 906bfca, we were not actually processing the righthand side of a multiple-column assignment in UPDATE as a row constructor: it was just a parenthesized list of expressions. Call it that rather than risking confusion by people who would expect the documented behaviors of row constructors to apply. Back-patch to 9.5; before that, the text correctly described the construct as a "list of independent expressions". Discussion: <16288.1479610770@sss.pgh.pa.us>
diff --git a/doc/src/sgml/ref/update.sgml b/doc/src/sgml/ref/update.sgml
@@ -422,9 +422,9 @@ UPDATE films SET kind = 'Dramatic' WHERE CURRENT OF c_films;
    According to the standard, the source value for a parenthesized sub-list of
    column names can be any row-valued expression yielding the correct number
    of columns.  <productname>PostgreSQL</productname> only allows the source
-   value to be a parenthesized list of expressions (a row constructor) or a
+   value to be a parenthesized list of expressions or a
    sub-<literal>SELECT</>.  An individual column's updated value can be
-   specified as <literal>DEFAULT</> in the row-constructor case, but not
+   specified as <literal>DEFAULT</> in the list-of-expressions case, but not
    inside a sub-<literal>SELECT</>.
   </para>
  </refsect1>
