diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/rewrite/rewriteHandler.c | 58 |
1 files changed, 33 insertions, 25 deletions
diff --git a/src/backend/rewrite/rewriteHandler.c b/src/backend/rewrite/rewriteHandler.c index e23d7005c94..505d5f4350b 100644 --- a/src/backend/rewrite/rewriteHandler.c +++ b/src/backend/rewrite/rewriteHandler.c @@ -7,7 +7,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteHandler.c,v 1.88 2001/01/24 19:43:05 momjian Exp $ + * $Header: /cvsroot/pgsql/src/backend/rewrite/rewriteHandler.c,v 1.89 2001/01/27 04:40:59 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -37,7 +37,7 @@ static RewriteInfo *gatherRewriteMeta(Query *parsetree, int rt_index, CmdType event, bool instead_flag); -static List *adjustJoinTreeList(Query *parsetree, int rt_index, bool *found); +static List *adjustJoinTreeList(Query *parsetree, bool removert, int rt_index); static void markQueryForUpdate(Query *qry, bool skipOldNew); static List *matchLocks(CmdType event, RuleLock *rulelocks, int varno, Query *parsetree); @@ -119,18 +119,25 @@ gatherRewriteMeta(Query *parsetree, /* * Each rule action's jointree should be the main parsetree's jointree - * plus that rule's jointree, but *without* the original rtindex + * plus that rule's jointree, but usually *without* the original rtindex * that we're replacing (if present, which it won't be for INSERT). - * Note that if the rule refers to OLD, its jointree will add back - * a reference to rt_index. + * Note that if the rule action refers to OLD, its jointree will add + * a reference to rt_index. If the rule action doesn't refer to OLD, + * but either the rule_qual or the user query quals do, then we need to + * keep the original rtindex in the jointree to provide data for the + * quals. We don't want the original rtindex to be joined twice, + * however, so avoid keeping it if the rule action mentions it. */ if (sub_action->jointree != NULL) { - bool found; - List *newjointree = adjustJoinTreeList(parsetree, - rt_index, - &found); - + bool keeporig; + List *newjointree; + + keeporig = (! rangeTableEntry_used((Node *) sub_action->jointree, + rt_index, 0)) && + (rangeTableEntry_used(info->rule_qual, rt_index, 0) || + rangeTableEntry_used(parsetree->jointree->quals, rt_index, 0)); + newjointree = adjustJoinTreeList(parsetree, !keeporig, rt_index); sub_action->jointree->fromlist = nconc(newjointree, sub_action->jointree->fromlist); } @@ -181,29 +188,30 @@ gatherRewriteMeta(Query *parsetree, } /* - * Copy the query's jointree list, and attempt to remove any occurrence - * of the given rt_index as a top-level join item (we do not look for it - * within join items; this is OK because we are only expecting to find it - * as an UPDATE or DELETE target relation, which will be at the top level - * of the join). Returns modified jointree list --- original list - * is not changed. *found is set to indicate if we found the rt_index. + * Copy the query's jointree list, and optionally attempt to remove any + * occurrence of the given rt_index as a top-level join item (we do not look + * for it within join items; this is OK because we are only expecting to find + * it as an UPDATE or DELETE target relation, which will be at the top level + * of the join). Returns modified jointree list --- original list is not + * changed. */ static List * -adjustJoinTreeList(Query *parsetree, int rt_index, bool *found) +adjustJoinTreeList(Query *parsetree, bool removert, int rt_index) { List *newjointree = listCopy(parsetree->jointree->fromlist); List *jjt; - *found = false; - foreach(jjt, newjointree) + if (removert) { - RangeTblRef *rtr = lfirst(jjt); - - if (IsA(rtr, RangeTblRef) && rtr->rtindex == rt_index) + foreach(jjt, newjointree) { - newjointree = lremove(rtr, newjointree); - *found = true; - break; + RangeTblRef *rtr = lfirst(jjt); + + if (IsA(rtr, RangeTblRef) && rtr->rtindex == rt_index) + { + newjointree = lremove(rtr, newjointree); + break; + } } } return newjointree; |