Doc: add information about partition locking

david-rowley · david-rowley · commit 2be0fe94bf20 · 2025-04-02T14:04:31.000+13:00
The documentation around locking of partitions for the executor startup phase of run-time partition pruning wasn't clear about which partitions were being locked. Fix that. Reviewed-by: Tender Wang <tndrwang@gmail.com> Discussion: https://postgr.es/m/CAApHDvp738G75HfkKcfXaf3a8s%3D6mmtOLh46tMD0D2hAo1UCzA%40mail.gmail.com Backpatch-through: 13
diff --git a/doc/src/sgml/ddl.sgml b/doc/src/sgml/ddl.sgml
@@ -4812,7 +4812,9 @@ EXPLAIN SELECT count(*) FROM measurement WHERE logdate &gt;= DATE '2008-01-01';
        It is possible to determine the number of partitions which were
        removed during this phase by observing the
        <quote>Subplans Removed</quote> property in the
-       <command>EXPLAIN</command> output.
+       <command>EXPLAIN</command> output.  It's important to note that any
+       partitions removed by the partition pruning done at this stage are
+       still locked at the beginning of execution.
       </para>
      </listitem>
 
