Fix problems with SQL functions returning rowtypes that have dropped

columns.  The returned tuple needs to have appropriate NULL columns
inserted so that it actually matches the declared rowtype.  It seemed
convenient to use a JunkFilter for this, so I made some cleanups and
simplifications in the JunkFilter code to allow it to support this
additional functionality.  (That in turn exposed a latent bug in
nodeAppend.c, which is that it was returning a tuple slot whose
descriptor didn't match its data.)  Also, move check_sql_fn_retval
out of pg_proc.c and into functions.c, where it seems to more naturally
belong.

1 files changed, 12 insertions, 12 deletions

diff --git a/src/backend/executor/nodeAppend.c b/src/backend/executor/nodeAppend.c
index f9e0463e969..8c939043fe0 100644
--- a/src/backend/executor/nodeAppend.c
+++ b/src/backend/executor/nodeAppend.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/executor/nodeAppend.c,v 1.60 2004/09/24 01:36:30 neilc Exp $
+ *	  $PostgreSQL: pgsql/src/backend/executor/nodeAppend.c,v 1.61 2004/10/07 18:38:49 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -220,7 +220,10 @@ ExecInitAppend(Append *node, EState *estate)
 	}
 
 	/*
-	 * initialize tuple type
+	 * Initialize tuple type.  (Note: in an inherited UPDATE situation,
+	 * the tuple type computed here corresponds to the parent table, which
+	 * is really a lie since tuples returned from child subplans will not
+	 * all look the same.)
 	 */
 	ExecAssignResultTypeFromTL(&appendstate->ps);
 	appendstate->ps.ps_ProjInfo = NULL;
@@ -282,13 +285,12 @@ ExecAppend(AppendState *node)
 	if (!TupIsNull(result))
 	{
 		/*
-		 * if the subplan gave us something then place a copy of whatever
-		 * we get into our result slot and return it.
-		 *
-		 * Note we rely on the subplan to retain ownership of the tuple for
-		 * as long as we need it --- we don't copy it.
+		 * if the subplan gave us something then return it as-is.  We do
+		 * NOT make use of the result slot that was set up in ExecInitAppend,
+		 * first because there's no reason to and second because it may have
+		 * the wrong tuple descriptor in inherited-UPDATE cases.
 		 */
-		return ExecStoreTuple(result->val, result_slot, InvalidBuffer, false);
+		return result;
 	}
 	else
 	{
@@ -303,13 +305,11 @@ ExecAppend(AppendState *node)
 
 		/*
 		 * return something from next node or an empty slot if all of our
-		 * subplans have been exhausted.
+		 * subplans have been exhausted.  The empty slot is the one set up
+		 * by ExecInitAppend.
 		 */
 		if (exec_append_initialize_next(node))
-		{
-			ExecSetSlotDescriptorIsNew(result_slot, true);
 			return ExecAppend(node);
-		}
 		else
 			return ExecClearTuple(result_slot);
 	}