diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/commands/trigger.c | 5 | ||||
| -rw-r--r-- | src/backend/executor/execMain.c | 32 | ||||
| -rw-r--r-- | src/include/executor/executor.h | 4 |
3 files changed, 32 insertions, 9 deletions
diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c index 8a5888a4044..7ed53be85d4 100644 --- a/src/backend/commands/trigger.c +++ b/src/backend/commands/trigger.c @@ -7,7 +7,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/commands/trigger.c,v 1.198 2006/01/05 10:07:45 petere Exp $ + * $PostgreSQL: pgsql/src/backend/commands/trigger.c,v 1.199 2006/01/12 21:48:52 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -1736,7 +1736,8 @@ ltrmark:; epqslot = EvalPlanQual(estate, relinfo->ri_RangeTableIndex, &update_ctid, - update_xmax); + update_xmax, + cid); if (!TupIsNull(epqslot)) { *tid = update_ctid; diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c index 1f70b2704ad..a0f9cfedd3f 100644 --- a/src/backend/executor/execMain.c +++ b/src/backend/executor/execMain.c @@ -26,7 +26,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/executor/execMain.c,v 1.264 2006/01/11 08:43:12 neilc Exp $ + * $PostgreSQL: pgsql/src/backend/executor/execMain.c,v 1.265 2006/01/12 21:48:53 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -1213,7 +1213,8 @@ lnext: ; newSlot = EvalPlanQual(estate, erm->rti, &update_ctid, - update_xmax); + update_xmax, + estate->es_snapshot->curcid); if (!TupIsNull(newSlot)) { slot = newSlot; @@ -1521,7 +1522,8 @@ ldelete:; epqslot = EvalPlanQual(estate, resultRelInfo->ri_RangeTableIndex, &update_ctid, - update_xmax); + update_xmax, + estate->es_snapshot->curcid); if (!TupIsNull(epqslot)) { *tupleid = update_ctid; @@ -1673,7 +1675,8 @@ lreplace:; epqslot = EvalPlanQual(estate, resultRelInfo->ri_RangeTableIndex, &update_ctid, - update_xmax); + update_xmax, + estate->es_snapshot->curcid); if (!TupIsNull(epqslot)) { *tupleid = update_ctid; @@ -1820,6 +1823,7 @@ ExecConstraints(ResultRelInfo *resultRelInfo, * rti - rangetable index of table containing tuple * *tid - t_ctid from the outdated tuple (ie, next updated version) * priorXmax - t_xmax from the outdated tuple + * curCid - command ID of current command of my transaction * * *tid is also an output parameter: it's modified to hold the TID of the * latest version of the tuple (note this may be changed even on failure) @@ -1829,7 +1833,7 @@ ExecConstraints(ResultRelInfo *resultRelInfo, */ TupleTableSlot * EvalPlanQual(EState *estate, Index rti, - ItemPointer tid, TransactionId priorXmax) + ItemPointer tid, TransactionId priorXmax, CommandId curCid) { evalPlanQual *epq; EState *epqstate; @@ -1906,6 +1910,24 @@ EvalPlanQual(EState *estate, Index rti, } /* + * If tuple was inserted by our own transaction, we have to check + * cmin against curCid: cmin >= curCid means our command cannot + * see the tuple, so we should ignore it. Without this we are + * open to the "Halloween problem" of indefinitely re-updating + * the same tuple. (We need not check cmax because + * HeapTupleSatisfiesDirty will consider a tuple deleted by + * our transaction dead, regardless of cmax.) We just checked + * that priorXmax == xmin, so we can test that variable instead + * of doing HeapTupleHeaderGetXmin again. + */ + if (TransactionIdIsCurrentTransactionId(priorXmax) && + HeapTupleHeaderGetCmin(tuple.t_data) >= curCid) + { + ReleaseBuffer(buffer); + return NULL; + } + + /* * We got tuple - now copy it for use by recheck query. */ copyTuple = heap_copytuple(&tuple); diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h index facb10a2e25..e320a8bf926 100644 --- a/src/include/executor/executor.h +++ b/src/include/executor/executor.h @@ -7,7 +7,7 @@ * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * - * $PostgreSQL: pgsql/src/include/executor/executor.h,v 1.123 2005/12/03 05:51:03 tgl Exp $ + * $PostgreSQL: pgsql/src/include/executor/executor.h,v 1.124 2006/01/12 21:48:53 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -98,7 +98,7 @@ extern bool ExecContextForcesOids(PlanState *planstate, bool *hasoids); extern void ExecConstraints(ResultRelInfo *resultRelInfo, TupleTableSlot *slot, EState *estate); extern TupleTableSlot *EvalPlanQual(EState *estate, Index rti, - ItemPointer tid, TransactionId priorXmax); + ItemPointer tid, TransactionId priorXmax, CommandId curCid); /* * prototypes from functions in execProcnode.c |