From 0a43e5466ca03fce433309c6de2a4272b79c1abb Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Tue, 7 Jan 2014 15:25:19 -0500 Subject: Fix LATERAL references to target table of UPDATE/DELETE. I failed to think much about UPDATE/DELETE when implementing LATERAL :-(. The implemented behavior ended up being that subqueries in the FROM or USING clause (respectively) could access the update/delete target table as though it were a lateral reference; which seems fine if they said LATERAL, but certainly ought to draw an error if they didn't. Fix it so you get a suitable error when you omit LATERAL. Per report from Emre Hasegeli. --- src/backend/parser/analyze.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) (limited to 'src/backend/parser/analyze.c') diff --git a/src/backend/parser/analyze.c b/src/backend/parser/analyze.c index a9d1fecff5c..2d8dc57d690 100644 --- a/src/backend/parser/analyze.c +++ b/src/backend/parser/analyze.c @@ -342,6 +342,7 @@ static Query * transformDeleteStmt(ParseState *pstate, DeleteStmt *stmt) { Query *qry = makeNode(Query); + ParseNamespaceItem *nsitem; Node *qual; qry->commandType = CMD_DELETE; @@ -360,8 +361,15 @@ transformDeleteStmt(ParseState *pstate, DeleteStmt *stmt) true, ACL_DELETE); + /* grab the namespace item made by setTargetTable */ + nsitem = (ParseNamespaceItem *) llast(pstate->p_namespace); + + /* there's no DISTINCT in DELETE */ qry->distinctClause = NIL; + /* subqueries in USING can see the result relation only via LATERAL */ + nsitem->p_lateral_only = true; + /* * The USING clause is non-standard SQL syntax, and is equivalent in * functionality to the FROM list that can be specified for UPDATE. The @@ -370,6 +378,9 @@ transformDeleteStmt(ParseState *pstate, DeleteStmt *stmt) */ transformFromClause(pstate, stmt->usingClause); + /* remaining clauses can see the result relation normally */ + nsitem->p_lateral_only = false; + qual = transformWhereClause(pstate, stmt->whereClause, EXPR_KIND_WHERE, "WHERE"); @@ -1889,6 +1900,7 @@ static Query * transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt) { Query *qry = makeNode(Query); + ParseNamespaceItem *nsitem; RangeTblEntry *target_rte; Node *qual; ListCell *origTargetList; @@ -1910,12 +1922,21 @@ transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt) true, ACL_UPDATE); + /* grab the namespace item made by setTargetTable */ + nsitem = (ParseNamespaceItem *) llast(pstate->p_namespace); + + /* subqueries in FROM can see the result relation only via LATERAL */ + nsitem->p_lateral_only = true; + /* * the FROM clause is non-standard SQL syntax. We used to be able to do * this with REPLACE in POSTQUEL so we keep the feature. */ transformFromClause(pstate, stmt->fromClause); + /* remaining clauses can see the result relation normally */ + nsitem->p_lateral_only = false; + qry->targetList = transformTargetList(pstate, stmt->targetList, EXPR_KIND_UPDATE_SOURCE); -- cgit v1.2.3