Give error message, rather than coredump, for utility statements in

conditional rules (rules with WHERE clauses).  We cannot support these
since there's noplace to hang a condition on a utility statement.
We caught the other case (attempt to attach a condition at rewrite time)
awhile ago, but this one escaped notice until now.

diff --git a/src/backend/parser/analyze.c b/src/backend/parser/analyze.c
index 0b6faf64227701461f2fac59f2ab43680bd31c09..2bef065b11aff35da922d2225c6d7ba28cae8d12 100644 (file)
--- a/src/backend/parser/analyze.c
+++ b/src/backend/parser/analyze.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- *     $Header: /cvsroot/pgsql/src/backend/parser/analyze.c,v 1.187 2001/05/22 16:37:15 petere Exp $
+ *     $Header: /cvsroot/pgsql/src/backend/parser/analyze.c,v 1.188 2001/06/04 16:17:30 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1742,13 +1742,15 @@ transformRuleStmt(ParseState *pstate, RuleStmt *stmt)
        }
        else
        {
-               List       *actions;
+               List       *oldactions;
+               List       *newactions = NIL;
 
                /*
                 * transform each statement, like parse_analyze()
                 */
-               foreach(actions, stmt->actions)
+               foreach(oldactions, stmt->actions)
                {
+                       Node       *action = (Node *) lfirst(oldactions);
                        ParseState *sub_pstate = make_parsestate(pstate->parentParseState);
                        Query      *sub_qry,
                                           *top_subqry;
@@ -1775,7 +1777,16 @@ transformRuleStmt(ParseState *pstate, RuleStmt *stmt)
                        addRTEtoQuery(sub_pstate, newrte, false, true);
 
                        /* Transform the rule action statement */
-                       top_subqry = transformStmt(sub_pstate, lfirst(actions));
+                       top_subqry = transformStmt(sub_pstate, action);
+
+                       /*
+                        * We cannot support utility-statement actions (eg NOTIFY)
+                        * with nonempty rule WHERE conditions, because there's no
+                        * way to make the utility action execute conditionally.
+                        */
+                       if (top_subqry->commandType == CMD_UTILITY &&
+                               stmt->whereClause != NULL)
+                               elog(ERROR, "Rules with WHERE conditions may only have SELECT, INSERT, UPDATE, or DELETE actions");
 
                        /*
                         * If the action is INSERT...SELECT, OLD/NEW have been pushed
@@ -1846,11 +1857,13 @@ transformRuleStmt(ParseState *pstate, RuleStmt *stmt)
                                sub_qry->jointree->fromlist = sub_pstate->p_joinlist;
                        }
 
-                       lfirst(actions) = top_subqry;
+                       newactions = lappend(newactions, top_subqry);
 
                        release_pstate_resources(sub_pstate);
                        pfree(sub_pstate);
                }
+
+               stmt->actions = newactions;
        }
 
        return qry;