Add a HINT per suggestion from Michael Glaesemann. Also, tweak OLD/NEW

test to avoid expensive contain_vars_of_level() scan in the normal case
where we're not inside a rule.

diff --git a/src/backend/parser/analyze.c b/src/backend/parser/analyze.c
index 4f7001b6f1ac4fdd9fe65cba835eeb2513f8ad06..a9971604de9be4cbf88aea5e275d198c82f77a45 100644 (file)
--- a/src/backend/parser/analyze.c
+++ b/src/backend/parser/analyze.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/backend/parser/analyze.c,v 1.341 2006/08/02 01:59:46 joe Exp $
+ * $PostgreSQL: pgsql/src/backend/parser/analyze.c,v 1.342 2006/08/02 13:58:52 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -745,10 +745,12 @@ transformInsertStmt(ParseState *pstate, InsertStmt *stmt,
         * construct to ensure that the values would be available while
         * evaluating the VALUES RTE.  This is a shame.  FIXME
         */
-       if (contain_vars_of_level((Node *) exprsLists, 0))
+       if (pstate->p_rtable != NIL &&
+           contain_vars_of_level((Node *) exprsLists, 0))
            ereport(ERROR,
                    (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-                    errmsg("VALUES must not contain OLD or NEW references")));
+                    errmsg("VALUES must not contain OLD or NEW references"),
+                    errhint("Use SELECT ... UNION ALL ... instead.")));
 
        /*
         * Generate the VALUES RTE
@@ -2264,10 +2266,12 @@ transformValuesClause(ParseState *pstate, SelectStmt *stmt)
     * construct to ensure that the values would be available while
     * evaluating the VALUES RTE.  This is a shame.  FIXME
     */
-   if (contain_vars_of_level((Node *) newExprsLists, 0))
+   if (list_length(pstate->p_rtable) != 1 &&
+       contain_vars_of_level((Node *) newExprsLists, 0))
        ereport(ERROR,
                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-                errmsg("VALUES must not contain OLD or NEW references")));
+                errmsg("VALUES must not contain OLD or NEW references"),
+                errhint("Use SELECT ... UNION ALL ... instead.")));
 
    qry->rtable = pstate->p_rtable;
    qry->jointree = makeFromExpr(pstate->p_joinlist, NULL);