*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/optimizer/plan/initsplan.c,v 1.60 2001/05/07 00:43:21 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/optimizer/plan/initsplan.c,v 1.61 2001/05/14 20:25:00 tgl Exp $
*
*-------------------------------------------------------------------------
*/
foreach(relid, rels)
{
- RelOptInfo *rel = get_base_rel(root, lfirsti(relid));
+ int relno = lfirsti(relid);
+ RelOptInfo *rel = get_base_rel(root, relno);
/*
* Since we do this bottom-up, any outer-rels previously marked
*/
Assert(is_subseti(rel->outerjoinset, outerrels));
+ /*
+ * Presently the executor cannot support FOR UPDATE marking of
+ * rels appearing on the nullable side of an outer join.
+ * (It's somewhat unclear what that would mean, anyway: what should
+ * we mark when a result row is generated from no element of the
+ * nullable relation?) So, complain if target rel is FOR UPDATE.
+ * It's sufficient to make this check once per rel, so do it only
+ * if rel wasn't already known nullable.
+ */
+ if (rel->outerjoinset == NIL)
+ {
+ if (intMember(relno, root->rowMarks))
+ elog(ERROR, "SELECT FOR UPDATE cannot be applied to the nullable side of an OUTER JOIN");
+ }
+
rel->outerjoinset = outerrels;
}
}