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Hope that execMain.c good merged.

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Fix for BEFORE ROW UPDATE triggers: result tuple may be different
(due to concurrent update) from one initially produced by top level plan.
This commit is contained in:
Vadim B. Mikheev
1999-01-29 11:56:01 +00:00
parent 1d41e88568
commit aaef7beb79
3 changed files with 51 additions and 43 deletions
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29
src/backend/commands/trigger.c
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@ -42,7 +42,7 @@ void FreeTriggerDesc(Relation relation);
static void DescribeTrigger(TriggerDesc *trigdesc, Trigger *trigger);
static HeapTuple GetTupleForTrigger(EState *estate, ItemPointer tid,
bool before);
TupleTableSlot **newSlot);
extern GlobalMemory CacheCxt;
@ -664,9 +664,10 @@ ExecBRDeleteTriggers(EState *estate, ItemPointer tupleid)
Trigger **trigger = rel->trigdesc->tg_before_row[TRIGGER_EVENT_DELETE];
HeapTuple trigtuple;
HeapTuple newtuple = NULL;
TupleTableSlot *newSlot;
int i;
trigtuple = GetTupleForTrigger(estate, tupleid, true);
trigtuple = GetTupleForTrigger(estate, tupleid, &newSlot);
if (trigtuple == NULL)
return false;
@ -701,7 +702,7 @@ ExecARDeleteTriggers(EState *estate, ItemPointer tupleid)
HeapTuple trigtuple;
int i;
trigtuple = GetTupleForTrigger(estate, tupleid, false);
trigtuple = GetTupleForTrigger(estate, tupleid, NULL);
Assert(trigtuple != NULL);
SaveTriggerData = (TriggerData *) palloc(sizeof(TriggerData));
@ -732,12 +733,20 @@ ExecBRUpdateTriggers(EState *estate, ItemPointer tupleid, HeapTuple newtuple)
HeapTuple trigtuple;
HeapTuple oldtuple;
HeapTuple intuple = newtuple;
TupleTableSlot *newSlot;
int i;
trigtuple = GetTupleForTrigger(estate, tupleid, true);
trigtuple = GetTupleForTrigger(estate, tupleid, &newSlot);
if (trigtuple == NULL)
return NULL;
/*
* In READ COMMITTED isolevel it's possible that newtuple
* was changed due to concurrent update.
*/
if (newSlot != NULL)
intuple = newtuple = ExecRemoveJunk(estate->es_junkFilter, newSlot);
SaveTriggerData = (TriggerData *) palloc(sizeof(TriggerData));
SaveTriggerData->tg_event =
TRIGGER_EVENT_UPDATE | TRIGGER_EVENT_ROW | TRIGGER_EVENT_BEFORE;
@ -770,7 +779,7 @@ ExecARUpdateTriggers(EState *estate, ItemPointer tupleid, HeapTuple newtuple)
HeapTuple trigtuple;
int i;
trigtuple = GetTupleForTrigger(estate, tupleid, false);
trigtuple = GetTupleForTrigger(estate, tupleid, NULL);
Assert(trigtuple != NULL);
SaveTriggerData = (TriggerData *) palloc(sizeof(TriggerData));
@ -794,20 +803,21 @@ ExecARUpdateTriggers(EState *estate, ItemPointer tupleid, HeapTuple newtuple)
extern TupleTableSlot *EvalPlanQual(EState *estate, Index rti, ItemPointer tid);
static HeapTuple
GetTupleForTrigger(EState *estate, ItemPointer tid, bool before)
GetTupleForTrigger(EState *estate, ItemPointer tid, TupleTableSlot **newSlot)
{
Relation relation = estate->es_result_relation_info->ri_RelationDesc;
HeapTupleData tuple;
HeapTuple result;
Buffer buffer;
if (before)
if (newSlot != NULL)
{
int test;
/*
* mark tuple for update
*/
*newSlot = NULL;
tuple.t_self = *tid;
ltrmark:;
test = heap_mark4update(relation, &tuple, &buffer);
@ -826,13 +836,14 @@ ltrmark:;
elog(ERROR, "Can't serialize access due to concurrent update");
else if (!(ItemPointerEquals(&(tuple.t_self), tid)))
{
TupleTableSlot *slot = EvalPlanQual(estate,
TupleTableSlot *epqslot = EvalPlanQual(estate,
estate->es_result_relation_info->ri_RangeTableIndex,
&(tuple.t_self));
if (!(TupIsNull(slot)))
if (!(TupIsNull(epqslot)))
{
*tid = tuple.t_self;
*newSlot = epqslot;
goto ltrmark;
}
}