Implement SQL-standard WITH clauses, including WITH RECURSIVE.

There are some unimplemented aspects: recursive queries must use UNION ALL
(should allow UNION too), and we don't have SEARCH or CYCLE clauses.
These might or might not get done for 8.4, but even without them it's a
pretty useful feature.

There are also a couple of small loose ends and definitional quibbles,
which I'll send a memo about to pgsql-hackers shortly.  But let's land
the patch now so we can get on with other development.

Yoshiyuki Asaba, with lots of help from Tatsuo Ishii and Tom Lane

1 files changed, 11 insertions, 3 deletions

diff --git a/src/backend/utils/cache/plancache.c b/src/backend/utils/cache/plancache.c
index 48addf3f539..fd535c0090d 100644
--- a/src/backend/utils/cache/plancache.c
+++ b/src/backend/utils/cache/plancache.c
@@ -35,7 +35,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/cache/plancache.c,v 1.22 2008/09/15 23:37:39 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/cache/plancache.c,v 1.23 2008/10/04 21:56:54 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -728,15 +728,23 @@ ScanQueryForLocks(Query *parsetree, bool acquire)
 		}
 	}
 
+	/* Recurse into subquery-in-WITH */
+	foreach(lc, parsetree->cteList)
+	{
+		CommonTableExpr *cte = (CommonTableExpr *) lfirst(lc);
+
+		ScanQueryForLocks((Query *) cte->ctequery, acquire);
+	}
+
 	/*
 	 * Recurse into sublink subqueries, too.  But we already did the ones in
-	 * the rtable.
+	 * the rtable and cteList.
 	 */
 	if (parsetree->hasSubLinks)
 	{
 		query_tree_walker(parsetree, ScanQueryWalker,
 						  (void *) &acquire,
-						  QTW_IGNORE_RT_SUBQUERIES);
+						  QTW_IGNORE_RC_SUBQUERIES);
 	}
 }