diff options
Diffstat (limited to 'src/backend/executor')
| -rw-r--r-- | src/backend/executor/execQual.c | 40 | ||||
| -rw-r--r-- | src/backend/executor/nodeTidscan.c | 19 |
2 files changed, 23 insertions, 36 deletions
diff --git a/src/backend/executor/execQual.c b/src/backend/executor/execQual.c index cc165006f5c..53ddc658197 100644 --- a/src/backend/executor/execQual.c +++ b/src/backend/executor/execQual.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/executor/execQual.c,v 1.222 2007/09/06 17:31:58 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/executor/execQual.c,v 1.223 2007/10/24 18:37:08 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -3694,45 +3694,17 @@ ExecEvalArrayCoerceExpr(ArrayCoerceExprState *astate, /* ---------------------------------------------------------------- * ExecEvalCurrentOfExpr * - * Normally, the planner will convert CURRENT OF into a TidScan qualification, - * but we have plain execQual support in case it doesn't. + * The planner must convert CURRENT OF into a TidScan qualification. + * So, we have to be able to do ExecInitExpr on a CurrentOfExpr, + * but we shouldn't ever actually execute it. * ---------------------------------------------------------------- */ static Datum ExecEvalCurrentOfExpr(ExprState *exprstate, ExprContext *econtext, bool *isNull, ExprDoneCond *isDone) { - CurrentOfExpr *cexpr = (CurrentOfExpr *) exprstate->expr; - bool result; - bool lisnull; - Oid tableoid; - ItemPointer tuple_tid; - ItemPointerData cursor_tid; - - if (isDone) - *isDone = ExprSingleResult; - *isNull = false; - - Assert(cexpr->cvarno != INNER); - Assert(cexpr->cvarno != OUTER); - Assert(!TupIsNull(econtext->ecxt_scantuple)); - /* Use slot_getattr to catch any possible mistakes */ - tableoid = DatumGetObjectId(slot_getattr(econtext->ecxt_scantuple, - TableOidAttributeNumber, - &lisnull)); - Assert(!lisnull); - tuple_tid = (ItemPointer) - DatumGetPointer(slot_getattr(econtext->ecxt_scantuple, - SelfItemPointerAttributeNumber, - &lisnull)); - Assert(!lisnull); - - if (execCurrentOf(cexpr, econtext, tableoid, &cursor_tid)) - result = ItemPointerEquals(&cursor_tid, tuple_tid); - else - result = false; - - return BoolGetDatum(result); + elog(ERROR, "CURRENT OF cannot be executed"); + return 0; /* keep compiler quiet */ } diff --git a/src/backend/executor/nodeTidscan.c b/src/backend/executor/nodeTidscan.c index 31a9828b6a1..8c217a442be 100644 --- a/src/backend/executor/nodeTidscan.c +++ b/src/backend/executor/nodeTidscan.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/executor/nodeTidscan.c,v 1.55 2007/06/11 22:22:40 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/executor/nodeTidscan.c,v 1.56 2007/10/24 18:37:08 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -68,6 +68,7 @@ TidListCreate(TidScanState *tidstate) tidList = (ItemPointerData *) palloc(numAllocTids * sizeof(ItemPointerData)); numTids = 0; + tidstate->tss_isCurrentOf = false; foreach(l, evalList) { @@ -165,6 +166,7 @@ TidListCreate(TidScanState *tidstate) numAllocTids * sizeof(ItemPointerData)); } tidList[numTids++] = cursor_tid; + tidstate->tss_isCurrentOf = true; } } else @@ -182,6 +184,9 @@ TidListCreate(TidScanState *tidstate) int lastTid; int i; + /* CurrentOfExpr could never appear OR'd with something else */ + Assert(!tidstate->tss_isCurrentOf); + qsort((void *) tidList, numTids, sizeof(ItemPointerData), itemptr_comparator); lastTid = 0; @@ -269,7 +274,8 @@ TidNext(TidScanState *node) /* * XXX shouldn't we check here to make sure tuple matches TID list? In - * runtime-key case this is not certain, is it? + * runtime-key case this is not certain, is it? However, in the + * WHERE CURRENT OF case it might not match anyway ... */ ExecStoreTuple(estate->es_evTuple[scanrelid - 1], @@ -319,6 +325,15 @@ TidNext(TidScanState *node) while (node->tss_TidPtr >= 0 && node->tss_TidPtr < numTids) { tuple->t_self = tidList[node->tss_TidPtr]; + + /* + * For WHERE CURRENT OF, the tuple retrieved from the cursor might + * since have been updated; if so, we should fetch the version that + * is current according to our snapshot. + */ + if (node->tss_isCurrentOf) + heap_get_latest_tid(heapRelation, snapshot, &tuple->t_self); + if (heap_fetch(heapRelation, snapshot, tuple, &buffer, false, NULL)) { /* |