Clarify docs about limitations of constraint exclusion with partitions

michaelpq · michaelpq · commit ea05b221c2ff · 2019-02-12T12:01:56.000+09:00
The current wording can confuse the reader about constraint exclusion being available at query execution, but this only applies to partition pruning. Reported-by: Shouyu Luo Author: David Rowley Reviewed-by: Chapman Flack, Amit Langote Discussion: https://postgr.es/m/15629-2ef8b22e61f8333f@postgresql.org
diff --git a/doc/src/sgml/ddl.sgml b/doc/src/sgml/ddl.sgml
@@ -4511,8 +4511,8 @@ EXPLAIN SELECT count(*) FROM measurement WHERE logdate &gt;= DATE '2008-01-01';
    <itemizedlist>
     <listitem>
      <para>
-      Constraint exclusion is only applied during query planning; unlike
-      partition pruning, it cannot be applied during query execution.
+      Constraint exclusion is only applied during query planning, unlike
+      partition pruning, which can also be applied during query execution.
      </para>
     </listitem>
 
