20 files changed, 217 insertions, 252 deletions
diff --git a/contrib/pgrowlocks/pgrowlocks.c b/contrib/pgrowlocks/pgrowlocks.c
index aaa132fbc47..fb19983bf86 100644
--- a/contrib/pgrowlocks/pgrowlocks.c
+++ b/contrib/pgrowlocks/pgrowlocks.c
@@ -1,5 +1,5 @@
 /*
- * $PostgreSQL: pgsql/contrib/pgrowlocks/pgrowlocks.c,v 1.7 2007/08/28 22:59:30 tgl Exp $
+ * $PostgreSQL: pgsql/contrib/pgrowlocks/pgrowlocks.c,v 1.8 2007/11/30 21:22:53 tgl Exp $
  *
  * Copyright (c) 2005-2006	Tatsuo Ishii
  *
@@ -117,8 +117,9 @@ pgrowlocks(PG_FUNCTION_ARGS)
 		/* must hold a buffer lock to call HeapTupleSatisfiesUpdate */
 		LockBuffer(scan->rs_cbuf, BUFFER_LOCK_SHARE);
 
-		if (HeapTupleSatisfiesUpdate(tuple->t_data, GetCurrentCommandId(), scan->rs_cbuf)
-			== HeapTupleBeingUpdated)
+		if (HeapTupleSatisfiesUpdate(tuple->t_data,
+									 GetCurrentCommandId(false),
+									 scan->rs_cbuf) == HeapTupleBeingUpdated)
 		{
 
 			char	  **values;
diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index 20027592b50..1a4fc92f1c2 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/heap/heapam.c,v 1.245 2007/11/15 21:14:32 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/heap/heapam.c,v 1.246 2007/11/30 21:22:53 tgl Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -1891,7 +1891,7 @@ heap_insert(Relation relation, HeapTuple tup, CommandId cid,
 Oid
 simple_heap_insert(Relation relation, HeapTuple tup)
 {
-	return heap_insert(relation, tup, GetCurrentCommandId(), true, true);
+	return heap_insert(relation, tup, GetCurrentCommandId(true), true, true);
 }
 
 /*
@@ -2174,7 +2174,7 @@ simple_heap_delete(Relation relation, ItemPointer tid)
 
 	result = heap_delete(relation, tid,
 						 &update_ctid, &update_xmax,
-						 GetCurrentCommandId(), InvalidSnapshot,
+						 GetCurrentCommandId(true), InvalidSnapshot,
 						 true /* wait for commit */ );
 	switch (result)
 	{
@@ -2817,7 +2817,7 @@ simple_heap_update(Relation relation, ItemPointer otid, HeapTuple tup)
 
 	result = heap_update(relation, otid, tup,
 						 &update_ctid, &update_xmax,
-						 GetCurrentCommandId(), InvalidSnapshot,
+						 GetCurrentCommandId(true), InvalidSnapshot,
 						 true /* wait for commit */ );
 	switch (result)
 	{
diff --git a/src/backend/access/heap/tuptoaster.c b/src/backend/access/heap/tuptoaster.c
index 0a8873f9945..f26fa9f4a6b 100644
--- a/src/backend/access/heap/tuptoaster.c
+++ b/src/backend/access/heap/tuptoaster.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/heap/tuptoaster.c,v 1.79 2007/11/15 21:14:32 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/heap/tuptoaster.c,v 1.80 2007/11/30 21:22:53 tgl Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -1086,7 +1086,7 @@ toast_save_datum(Relation rel, Datum value,
 	TupleDesc	toasttupDesc;
 	Datum		t_values[3];
 	bool		t_isnull[3];
-	CommandId	mycid = GetCurrentCommandId();
+	CommandId	mycid = GetCurrentCommandId(true);
 	struct varlena *result;
 	struct varatt_external toast_pointer;
 	struct
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 04804c38711..ce0dd812819 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/transam/xact.c,v 1.253 2007/11/15 21:14:32 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/transam/xact.c,v 1.254 2007/11/30 21:22:53 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -161,6 +161,7 @@ static TransactionState CurrentTransactionState = &TopTransactionStateData;
  */
 static SubTransactionId currentSubTransactionId;
 static CommandId currentCommandId;
+static bool currentCommandIdUsed;
 
 /*
  * xactStartTimestamp is the value of transaction_timestamp().
@@ -435,11 +436,18 @@ GetCurrentSubTransactionId(void)
 
 /*
  *	GetCurrentCommandId
+ *
+ * "used" must be TRUE if the caller intends to use the command ID to mark
+ * inserted/updated/deleted tuples.  FALSE means the ID is being fetched
+ * for read-only purposes (ie, as a snapshot validity cutoff).  See
+ * CommandCounterIncrement() for discussion.
  */
 CommandId
-GetCurrentCommandId(void)
+GetCurrentCommandId(bool used)
 {
 	/* this is global to a transaction, not subtransaction-local */
+	if (used)
+		currentCommandIdUsed = true;
 	return currentCommandId;
 }
 
@@ -566,25 +574,50 @@ TransactionIdIsCurrentTransactionId(TransactionId xid)
 void
 CommandCounterIncrement(void)
 {
-	currentCommandId += 1;
-	if (currentCommandId == FirstCommandId)		/* check for overflow */
+	/*
+	 * If the current value of the command counter hasn't been "used" to
+	 * mark tuples, we need not increment it, since there's no need to
+	 * distinguish a read-only command from others.  This helps postpone
+	 * command counter overflow, and keeps no-op CommandCounterIncrement
+	 * operations cheap.
+	 */
+	if (currentCommandIdUsed)
 	{
-		currentCommandId -= 1;
-		ereport(ERROR,
-				(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
+		currentCommandId += 1;
+		if (currentCommandId == FirstCommandId)	/* check for overflow */
+		{
+			currentCommandId -= 1;
+			ereport(ERROR,
+					(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
 		  errmsg("cannot have more than 2^32-1 commands in a transaction")));
-	}
+		}
+		currentCommandIdUsed = false;
 
-	/* Propagate new command ID into static snapshots, if set */
-	if (SerializableSnapshot)
-		SerializableSnapshot->curcid = currentCommandId;
-	if (LatestSnapshot)
-		LatestSnapshot->curcid = currentCommandId;
+		/* Propagate new command ID into static snapshots, if set */
+		if (SerializableSnapshot)
+			SerializableSnapshot->curcid = currentCommandId;
+		if (LatestSnapshot)
+			LatestSnapshot->curcid = currentCommandId;
+
+		/*
+		 * Make any catalog changes done by the just-completed command
+		 * visible in the local syscache.  We obviously don't need to do
+		 * this after a read-only command.  (But see hacks in inval.c
+		 * to make real sure we don't think a command that queued inval
+		 * messages was read-only.)
+		 */
+		AtCommit_LocalCache();
+	}
 
 	/*
-	 * make cache changes visible to me.
+	 * Make any other backends' catalog changes visible to me.
+	 *
+	 * XXX this is probably in the wrong place: CommandCounterIncrement
+	 * should be purely a local operation, most likely.  However fooling
+	 * with this will affect asynchronous cross-backend interactions,
+	 * which doesn't seem like a wise thing to do in late beta, so save
+	 * improving this for another day - tgl 2007-11-30
 	 */
-	AtCommit_LocalCache();
 	AtStart_Cache();
 }
 
@@ -1416,6 +1449,7 @@ StartTransaction(void)
 	s->subTransactionId = TopSubTransactionId;
 	currentSubTransactionId = TopSubTransactionId;
 	currentCommandId = FirstCommandId;
+	currentCommandIdUsed = false;
 
 	/*
 	 * must initialize resource-management stuff first
@@ -4007,13 +4041,14 @@ ShowTransactionStateRec(TransactionState s)
 
 	/* use ereport to suppress computation if msg will not be printed */
 	ereport(DEBUG3,
-			(errmsg_internal("name: %s; blockState: %13s; state: %7s, xid/subid/cid: %u/%u/%u, nestlvl: %d, children: %s",
+			(errmsg_internal("name: %s; blockState: %13s; state: %7s, xid/subid/cid: %u/%u/%u%s, nestlvl: %d, children: %s",
 							 PointerIsValid(s->name) ? s->name : "unnamed",
 							 BlockStateAsString(s->blockState),
 							 TransStateAsString(s->state),
 							 (unsigned int) s->transactionId,
 							 (unsigned int) s->subTransactionId,
 							 (unsigned int) currentCommandId,
+							 currentCommandIdUsed ? " (used)" : "",
 							 s->nestingLevel,
 							 nodeToString(s->childXids))));
 }
diff --git a/src/backend/commands/async.c b/src/backend/commands/async.c
index 55b99f8c922..c32dd2b19fc 100644
--- a/src/backend/commands/async.c
+++ b/src/backend/commands/async.c
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/async.c,v 1.136 2007/04/12 06:53:46 neilc Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/async.c,v 1.137 2007/11/30 21:22:53 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -562,7 +562,8 @@ AtCommit_Notify(void)
 				 */
 				result = heap_update(lRel, &lTuple->t_self, rTuple,
 									 &update_ctid, &update_xmax,
-									 GetCurrentCommandId(), InvalidSnapshot,
+									 GetCurrentCommandId(true),
+									 InvalidSnapshot,
 									 false /* no wait for commit */ );
 				switch (result)
 				{
diff --git a/src/backend/commands/copy.c b/src/backend/commands/copy.c
index ef7e04ca286..c68d828fea0 100644
--- a/src/backend/commands/copy.c
+++ b/src/backend/commands/copy.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/copy.c,v 1.288 2007/11/15 21:14:33 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/copy.c,v 1.289 2007/11/30 21:22:53 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1033,7 +1033,7 @@ DoCopy(const CopyStmt *stmt, const char *queryString)
 		 * which COPY can be invoked, I think it's OK, because the active
 		 * snapshot shouldn't be shared with anything else anyway.)
 		 */
-		ActiveSnapshot->curcid = GetCurrentCommandId();
+		ActiveSnapshot->curcid = GetCurrentCommandId(false);
 
 		/* Create dest receiver for COPY OUT */
 		dest = CreateDestReceiver(DestCopyOut, NULL);
@@ -1637,7 +1637,7 @@ CopyFrom(CopyState cstate)
 	ExprContext *econtext;		/* used for ExecEvalExpr for default atts */
 	MemoryContext oldcontext = CurrentMemoryContext;
 	ErrorContextCallback errcontext;
-	CommandId	mycid = GetCurrentCommandId();
+	CommandId	mycid = GetCurrentCommandId(true);
 	bool		use_wal = true; /* by default, use WAL logging */
 	bool		use_fsm = true; /* by default, use FSM for free space */
 
diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c
index a9aa2cb3e13..f77f8cdc5ec 100644
--- a/src/backend/commands/explain.c
+++ b/src/backend/commands/explain.c
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1994-5, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/explain.c,v 1.167 2007/11/15 22:25:15 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/explain.c,v 1.168 2007/11/30 21:22:54 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -233,7 +233,7 @@ ExplainOnePlan(PlannedStmt *plannedstmt, ParamListInfo params,
 	 * EXPLAIN can be invoked, I think it's OK, because the active snapshot
 	 * shouldn't be shared with anything else anyway.)
 	 */
-	ActiveSnapshot->curcid = GetCurrentCommandId();
+	ActiveSnapshot->curcid = GetCurrentCommandId(false);
 
 	/* Create a QueryDesc requesting no output */
 	queryDesc = CreateQueryDesc(plannedstmt,
diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c
index 7dc19505342..1b66bd22ba8 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 1.224 2007/11/16 01:51:22 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/trigger.c,v 1.225 2007/11/30 21:22:54 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -51,7 +51,6 @@ static void InsertTrigger(TriggerDesc *trigdesc, Trigger *trigger, int indx);
 static HeapTuple GetTupleForTrigger(EState *estate,
 				   ResultRelInfo *relinfo,
 				   ItemPointer tid,
-				   CommandId cid,
 				   TupleTableSlot **newSlot);
 static HeapTuple ExecCallTriggerFunc(TriggerData *trigdata,
 					int tgindx,
@@ -1801,8 +1800,7 @@ ExecASDeleteTriggers(EState *estate, ResultRelInfo *relinfo)
 
 bool
 ExecBRDeleteTriggers(EState *estate, ResultRelInfo *relinfo,
-					 ItemPointer tupleid,
-					 CommandId cid)
+					 ItemPointer tupleid)
 {
 	TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
 	int			ntrigs = trigdesc->n_before_row[TRIGGER_EVENT_DELETE];
@@ -1814,7 +1812,7 @@ ExecBRDeleteTriggers(EState *estate, ResultRelInfo *relinfo,
 	TupleTableSlot *newSlot;
 	int			i;
 
-	trigtuple = GetTupleForTrigger(estate, relinfo, tupleid, cid, &newSlot);
+	trigtuple = GetTupleForTrigger(estate, relinfo, tupleid, &newSlot);
 	if (trigtuple == NULL)
 		return false;
 
@@ -1871,9 +1869,7 @@ ExecARDeleteTriggers(EState *estate, ResultRelInfo *relinfo,
 	if (trigdesc && trigdesc->n_after_row[TRIGGER_EVENT_DELETE] > 0)
 	{
 		HeapTuple	trigtuple = GetTupleForTrigger(estate, relinfo,
-												   tupleid,
-												   (CommandId) 0,
-												   NULL);
+												   tupleid, NULL);
 
 		AfterTriggerSaveEvent(relinfo, TRIGGER_EVENT_DELETE,
 							  true, trigtuple, NULL);
@@ -1952,8 +1948,7 @@ ExecASUpdateTriggers(EState *estate, ResultRelInfo *relinfo)
 
 HeapTuple
 ExecBRUpdateTriggers(EState *estate, ResultRelInfo *relinfo,
-					 ItemPointer tupleid, HeapTuple newtuple,
-					 CommandId cid)
+					 ItemPointer tupleid, HeapTuple newtuple)
 {
 	TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
 	int			ntrigs = trigdesc->n_before_row[TRIGGER_EVENT_UPDATE];
@@ -1965,7 +1960,7 @@ ExecBRUpdateTriggers(EState *estate, ResultRelInfo *relinfo,
 	TupleTableSlot *newSlot;
 	int			i;
 
-	trigtuple = GetTupleForTrigger(estate, relinfo, tupleid, cid, &newSlot);
+	trigtuple = GetTupleForTrigger(estate, relinfo, tupleid, &newSlot);
 	if (trigtuple == NULL)
 		return NULL;
 
@@ -2025,9 +2020,7 @@ ExecARUpdateTriggers(EState *estate, ResultRelInfo *relinfo,
 	if (trigdesc && trigdesc->n_after_row[TRIGGER_EVENT_UPDATE] > 0)
 	{
 		HeapTuple	trigtuple = GetTupleForTrigger(estate, relinfo,
-												   tupleid,
-												   (CommandId) 0,
-												   NULL);
+												   tupleid, NULL);
 
 		AfterTriggerSaveEvent(relinfo, TRIGGER_EVENT_UPDATE,
 							  true, trigtuple, newtuple);
@@ -2038,7 +2031,7 @@ ExecARUpdateTriggers(EState *estate, ResultRelInfo *relinfo,
 
 static HeapTuple
 GetTupleForTrigger(EState *estate, ResultRelInfo *relinfo,
-				   ItemPointer tid, CommandId cid,
+				   ItemPointer tid,
 				   TupleTableSlot **newSlot)
 {
 	Relation	relation = relinfo->ri_RelationDesc;
@@ -2060,7 +2053,8 @@ GetTupleForTrigger(EState *estate, ResultRelInfo *relinfo,
 ltrmark:;
 		tuple.t_self = *tid;
 		test = heap_lock_tuple(relation, &tuple, &buffer,
-							   &update_ctid, &update_xmax, cid,
+							   &update_ctid, &update_xmax,
+							   estate->es_output_cid,
 							   LockTupleExclusive, false);
 		switch (test)
 		{
@@ -2086,8 +2080,7 @@ ltrmark:;
 					epqslot = EvalPlanQual(estate,
 										   relinfo->ri_RangeTableIndex,
 										   &update_ctid,
-										   update_xmax,
-										   cid);
+										   update_xmax);
 					if (!TupIsNull(epqslot))
 					{
 						*tid = update_ctid;
diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c
index 4b6ad47adb0..5886234a1e8 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 1.300 2007/11/15 22:25:15 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/executor/execMain.c,v 1.301 2007/11/30 21:22:54 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -161,6 +161,30 @@ ExecutorStart(QueryDesc *queryDesc, int eflags)
 			palloc0(queryDesc->plannedstmt->nParamExec * sizeof(ParamExecData));
 
 	/*
+	 * If non-read-only query, set the command ID to mark output tuples with
+	 */
+	switch (queryDesc->operation)
+	{
+		case CMD_SELECT:
+			/* SELECT INTO and SELECT FOR UPDATE/SHARE need to mark tuples */
+			if (queryDesc->plannedstmt->intoClause != NULL ||
+				queryDesc->plannedstmt->rowMarks != NIL)
+				estate->es_output_cid = GetCurrentCommandId(true);
+			break;
+
+		case CMD_INSERT:
+		case CMD_DELETE:
+		case CMD_UPDATE:
+			estate->es_output_cid = GetCurrentCommandId(true);
+			break;
+
+		default:
+			elog(ERROR, "unrecognized operation code: %d",
+				 (int) queryDesc->operation);
+			break;
+	}
+
+	/*
 	 * Copy other important information into the EState
 	 */
 	estate->es_snapshot = queryDesc->snapshot;
@@ -1285,7 +1309,7 @@ lnext:	;
 
 					test = heap_lock_tuple(erm->relation, &tuple, &buffer,
 										   &update_ctid, &update_xmax,
-										   estate->es_snapshot->curcid,
+										   estate->es_output_cid,
 										   lockmode, erm->noWait);
 					ReleaseBuffer(buffer);
 					switch (test)
@@ -1309,8 +1333,7 @@ lnext:	;
 								newSlot = EvalPlanQual(estate,
 													   erm->rti,
 													   &update_ctid,
-													   update_xmax,
-												estate->es_snapshot->curcid);
+													   update_xmax);
 								if (!TupIsNull(newSlot))
 								{
 									slot = planSlot = newSlot;
@@ -1503,7 +1526,7 @@ ExecInsert(TupleTableSlot *slot,
 	 * t_self field.
 	 */
 	newId = heap_insert(resultRelationDesc, tuple,
-						estate->es_snapshot->curcid,
+						estate->es_output_cid,
 						true, true);
 
 	IncrAppended();
@@ -1557,8 +1580,7 @@ ExecDelete(ItemPointer tupleid,
 	{
 		bool		dodelete;
 
-		dodelete = ExecBRDeleteTriggers(estate, resultRelInfo, tupleid,
-										estate->es_snapshot->curcid);
+		dodelete = ExecBRDeleteTriggers(estate, resultRelInfo, tupleid);
 
 		if (!dodelete)			/* "do nothing" */
 			return;
@@ -1575,7 +1597,7 @@ ExecDelete(ItemPointer tupleid,
 ldelete:;
 	result = heap_delete(resultRelationDesc, tupleid,
 						 &update_ctid, &update_xmax,
-						 estate->es_snapshot->curcid,
+						 estate->es_output_cid,
 						 estate->es_crosscheck_snapshot,
 						 true /* wait for commit */ );
 	switch (result)
@@ -1599,8 +1621,7 @@ ldelete:;
 				epqslot = EvalPlanQual(estate,
 									   resultRelInfo->ri_RangeTableIndex,
 									   &update_ctid,
-									   update_xmax,
-									   estate->es_snapshot->curcid);
+									   update_xmax);
 				if (!TupIsNull(epqslot))
 				{
 					*tupleid = update_ctid;
@@ -1708,8 +1729,7 @@ ExecUpdate(TupleTableSlot *slot,
 		HeapTuple	newtuple;
 
 		newtuple = ExecBRUpdateTriggers(estate, resultRelInfo,
-										tupleid, tuple,
-										estate->es_snapshot->curcid);
+										tupleid, tuple);
 
 		if (newtuple == NULL)	/* "do nothing" */
 			return;
@@ -1755,7 +1775,7 @@ lreplace:;
 	 */
 	result = heap_update(resultRelationDesc, tupleid, tuple,
 						 &update_ctid, &update_xmax,
-						 estate->es_snapshot->curcid,
+						 estate->es_output_cid,
 						 estate->es_crosscheck_snapshot,
 						 true /* wait for commit */ );
 	switch (result)
@@ -1779,8 +1799,7 @@ lreplace:;
 				epqslot = EvalPlanQual(estate,
 									   resultRelInfo->ri_RangeTableIndex,
 									   &update_ctid,
-									   update_xmax,
-									   estate->es_snapshot->curcid);
+									   update_xmax);
 				if (!TupIsNull(epqslot))
 				{
 					*tupleid = update_ctid;
@@ -1973,7 +1992,6 @@ ExecProcessReturning(ProjectionInfo *projectReturning,
  *	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)
@@ -1983,7 +2001,7 @@ ExecProcessReturning(ProjectionInfo *projectReturning,
  */
 TupleTableSlot *
 EvalPlanQual(EState *estate, Index rti,
-			 ItemPointer tid, TransactionId priorXmax, CommandId curCid)
+			 ItemPointer tid, TransactionId priorXmax)
 {
 	evalPlanQual *epq;
 	EState	   *epqstate;
@@ -2063,17 +2081,17 @@ 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
+			 * cmin against es_output_cid: cmin >= current CID 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)
+				HeapTupleHeaderGetCmin(tuple.t_data) >= estate->es_output_cid)
 			{
 				ReleaseBuffer(buffer);
 				return NULL;
@@ -2360,6 +2378,7 @@ EvalPlanQualStart(evalPlanQual *epq, EState *estate, evalPlanQual *priorepq)
 	epqstate->es_snapshot = estate->es_snapshot;
 	epqstate->es_crosscheck_snapshot = estate->es_crosscheck_snapshot;
 	epqstate->es_range_table = estate->es_range_table;
+	epqstate->es_output_cid = estate->es_output_cid;
 	epqstate->es_result_relations = estate->es_result_relations;
 	epqstate->es_num_result_relations = estate->es_num_result_relations;
 	epqstate->es_result_relation_info = estate->es_result_relation_info;
@@ -2718,7 +2737,7 @@ intorel_receive(TupleTableSlot *slot, DestReceiver *self)
 
 	heap_insert(estate->es_into_relation_descriptor,
 				tuple,
-				estate->es_snapshot->curcid,
+				estate->es_output_cid,
 				estate->es_into_relation_use_wal,
 				false);			/* never any point in using FSM */
 
diff --git a/src/backend/executor/execUtils.c b/src/backend/executor/execUtils.c
index 230d5c919f2..12ddc910f47 100644
--- a/src/backend/executor/execUtils.c
+++ b/src/backend/executor/execUtils.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/executor/execUtils.c,v 1.152 2007/11/15 21:14:34 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/executor/execUtils.c,v 1.153 2007/11/30 21:22:54 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -178,6 +178,8 @@ CreateExecutorState(void)
 	estate->es_crosscheck_snapshot = InvalidSnapshot;	/* no crosscheck */
 	estate->es_range_table = NIL;
 
+	estate->es_output_cid = (CommandId) 0;
+
 	estate->es_result_relations = NULL;
 	estate->es_num_result_relations = 0;
 	estate->es_result_relation_info = NULL;
diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index a5601ecdfca..e08e91cb0a0 100644
--- a/src/backend/executor/spi.c
+++ b/src/backend/executor/spi.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/executor/spi.c,v 1.185 2007/11/30 18:38:34 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/executor/spi.c,v 1.186 2007/11/30 21:22:54 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1593,7 +1593,7 @@ _SPI_execute_plan(SPIPlanPtr plan, Datum *Values, const char *Nulls,
 					 */
 					ActiveSnapshot = CopySnapshot(snapshot);
 					if (!read_only)
-						ActiveSnapshot->curcid = GetCurrentCommandId();
+						ActiveSnapshot->curcid = GetCurrentCommandId(false);
 				}
 
 				if (IsA(stmt, PlannedStmt) &&
diff --git a/src/backend/storage/ipc/procarray.c b/src/backend/storage/ipc/procarray.c
index d7c8d706fd9..156f947604e 100644
--- a/src/backend/storage/ipc/procarray.c
+++ b/src/backend/storage/ipc/procarray.c
@@ -23,7 +23,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/storage/ipc/procarray.c,v 1.37 2007/11/15 21:14:38 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/storage/ipc/procarray.c,v 1.38 2007/11/30 21:22:54 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -814,7 +814,7 @@ GetSnapshotData(Snapshot snapshot, bool serializable)
 	snapshot->xcnt = count;
 	snapshot->subxcnt = subcount;
 
-	snapshot->curcid = GetCurrentCommandId();
+	snapshot->curcid = GetCurrentCommandId(false);
 
 	return snapshot;
 }
diff --git a/src/backend/utils/cache/inval.c b/src/backend/utils/cache/inval.c
index 844dbc2be06..803727f0840 100644
--- a/src/backend/utils/cache/inval.c
+++ b/src/backend/utils/cache/inval.c
@@ -80,7 +80,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/cache/inval.c,v 1.81 2007/11/15 21:14:39 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/cache/inval.c,v 1.82 2007/11/30 21:22:54 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -403,6 +403,14 @@ RegisterRelcacheInvalidation(Oid dbId, Oid relId)
 								   dbId, relId);
 
 	/*
+	 * Most of the time, relcache invalidation is associated with system
+	 * catalog updates, but there are a few cases where it isn't.  Quick
+	 * hack to ensure that the next CommandCounterIncrement() will think
+	 * that we need to do CommandEndInvalidationMessages().
+	 */
+	(void) GetCurrentCommandId(true);
+
+	/*
 	 * If the relation being invalidated is one of those cached in the
 	 * relcache init file, mark that we need to zap that file at commit.
 	 */
@@ -420,6 +428,11 @@ RegisterSmgrInvalidation(RelFileNode rnode)
 {
 	AddSmgrInvalidationMessage(&transInvalInfo->CurrentCmdInvalidMsgs,
 							   rnode);
+
+	/*
+	 * As above, just in case there is not an associated catalog change.
+	 */
+	(void) GetCurrentCommandId(true);
 }
 
 /*
diff --git a/src/backend/utils/time/tqual.c b/src/backend/utils/time/tqual.c
index 4c128e4446b..dad379573c2 100644
--- a/src/backend/utils/time/tqual.c
+++ b/src/backend/utils/time/tqual.c
@@ -31,7 +31,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/time/tqual.c,v 1.107 2007/11/15 21:14:41 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/time/tqual.c,v 1.108 2007/11/30 21:22:54 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -382,7 +382,7 @@ HeapTupleSatisfiesNow(HeapTupleHeader tuple, Snapshot snapshot, Buffer buffer)
 		}
 		else if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmin(tuple)))
 		{
-			if (HeapTupleHeaderGetCmin(tuple) >= GetCurrentCommandId())
+			if (HeapTupleHeaderGetCmin(tuple) >= GetCurrentCommandId(false))
 				return false;	/* inserted after scan started */
 
 			if (tuple->t_infomask & HEAP_XMAX_INVALID)	/* xid invalid */
@@ -401,7 +401,7 @@ HeapTupleSatisfiesNow(HeapTupleHeader tuple, Snapshot snapshot, Buffer buffer)
 				return true;
 			}
 
-			if (HeapTupleHeaderGetCmax(tuple) >= GetCurrentCommandId())
+			if (HeapTupleHeaderGetCmax(tuple) >= GetCurrentCommandId(false))
 				return true;	/* deleted after scan started */
 			else
 				return false;	/* deleted before scan started */
@@ -443,7 +443,7 @@ HeapTupleSatisfiesNow(HeapTupleHeader tuple, Snapshot snapshot, Buffer buffer)
 	{
 		if (tuple->t_infomask & HEAP_IS_LOCKED)
 			return true;
-		if (HeapTupleHeaderGetCmax(tuple) >= GetCurrentCommandId())
+		if (HeapTupleHeaderGetCmax(tuple) >= GetCurrentCommandId(false))
 			return true;		/* deleted after scan started */
 		else
 			return false;		/* deleted before scan started */
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 8a311dda3ba..9a6fa607a0e 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/access/xact.h,v 1.91 2007/11/15 21:14:42 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/access/xact.h,v 1.92 2007/11/30 21:22:54 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -143,7 +143,7 @@ extern TransactionId GetTopTransactionIdIfAny(void);
 extern TransactionId GetCurrentTransactionId(void);
 extern TransactionId GetCurrentTransactionIdIfAny(void);
 extern SubTransactionId GetCurrentSubTransactionId(void);
-extern CommandId GetCurrentCommandId(void);
+extern CommandId GetCurrentCommandId(bool used);
 extern TimestampTz GetCurrentTransactionStartTimestamp(void);
 extern TimestampTz GetCurrentStatementStartTimestamp(void);
 extern TimestampTz GetCurrentTransactionStopTimestamp(void);
diff --git a/src/include/commands/trigger.h b/src/include/commands/trigger.h
index 69ad97b4ec8..5a1d50edf94 100644
--- a/src/include/commands/trigger.h
+++ b/src/include/commands/trigger.h
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/commands/trigger.h,v 1.63 2007/11/15 21:14:43 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/commands/trigger.h,v 1.64 2007/11/30 21:22:54 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -124,8 +124,7 @@ extern void ExecASDeleteTriggers(EState *estate,
 					 ResultRelInfo *relinfo);
 extern bool ExecBRDeleteTriggers(EState *estate,
 					 ResultRelInfo *relinfo,
-					 ItemPointer tupleid,
-					 CommandId cid);
+					 ItemPointer tupleid);
 extern void ExecARDeleteTriggers(EState *estate,
 					 ResultRelInfo *relinfo,
 					 ItemPointer tupleid);
@@ -136,8 +135,7 @@ extern void ExecASUpdateTriggers(EState *estate,
 extern HeapTuple ExecBRUpdateTriggers(EState *estate,
 					 ResultRelInfo *relinfo,
 					 ItemPointer tupleid,
-					 HeapTuple newtuple,
-					 CommandId cid);
+					 HeapTuple newtuple);
 extern void ExecARUpdateTriggers(EState *estate,
 					 ResultRelInfo *relinfo,
 					 ItemPointer tupleid,
diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h
index 08b97e3adfc..78a0a2560a3 100644
--- a/src/include/executor/executor.h
+++ b/src/include/executor/executor.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/executor/executor.h,v 1.144 2007/11/15 22:25:17 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/executor/executor.h,v 1.145 2007/11/30 21:22:54 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -143,7 +143,7 @@ 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, CommandId curCid);
+			 ItemPointer tid, TransactionId priorXmax);
 extern PlanState *ExecGetActivePlanTree(QueryDesc *queryDesc);
 extern DestReceiver *CreateIntoRelDestReceiver(void);
 
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index ca0e9c8fa78..a140a7533d4 100644
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/nodes/execnodes.h,v 1.181 2007/11/15 22:25:17 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/nodes/execnodes.h,v 1.182 2007/11/30 21:22:54 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -311,6 +311,9 @@ typedef struct EState
 	Snapshot	es_crosscheck_snapshot; /* crosscheck time qual for RI */
 	List	   *es_range_table; /* List of RangeTblEntry */
 
+	/* If query can insert/delete tuples, the command ID to mark them with */
+	CommandId	es_output_cid;
+
 	/* Info about target table for insert/update/delete queries: */
 	ResultRelInfo *es_result_relations; /* array of ResultRelInfos */
 	int			es_num_result_relations;		/* length of array */
diff --git a/src/test/regress/expected/combocid.out b/src/test/regress/expected/combocid.out
index 14e45fe4893..b63894c2837 100644
--- a/src/test/regress/expected/combocid.out
+++ b/src/test/regress/expected/combocid.out
@@ -4,66 +4,16 @@
 CREATE TEMP TABLE combocidtest (foobar int);
 BEGIN;
 -- a few dummy ops to push up the CommandId counter
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
 INSERT INTO combocidtest VALUES (1);
 INSERT INTO combocidtest VALUES (2);
 SELECT ctid,cmin,* FROM combocidtest;
@@ -79,8 +29,8 @@ UPDATE combocidtest SET foobar = foobar + 10;
 SELECT ctid,cmin,* FROM combocidtest;
  ctid  | cmin | foobar 
 -------+------+--------
- (0,3) |   13 |     11
- (0,4) |   13 |     12
+ (0,3) |   12 |     11
+ (0,4) |   12 |     12
 (2 rows)
 
 ROLLBACK TO s1;
@@ -109,8 +59,8 @@ DELETE FROM combocidtest;
 FETCH ALL FROM c;
  ctid  | cmin | foobar 
 -------+------+--------
- (0,1) |    2 |      1
- (0,2) |    2 |      2
+ (0,1) |    1 |      1
+ (0,2) |    1 |      2
  (0,5) |    0 |    333
 (3 rows)
 
@@ -118,79 +68,29 @@ ROLLBACK;
 SELECT ctid,cmin,* FROM combocidtest;
  ctid  | cmin | foobar 
 -------+------+--------
- (0,1) |    2 |      1
- (0,2) |    2 |      2
+ (0,1) |    1 |      1
+ (0,2) |    1 |      2
 (2 rows)
 
 -- check behavior with locked tuples
 BEGIN;
 -- a few dummy ops to push up the CommandId counter
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
-SELECT 1;
- ?column? 
-----------
-        1
-(1 row)
-
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
 INSERT INTO combocidtest VALUES (444);
 SELECT ctid,cmin,* FROM combocidtest;
  ctid  | cmin | foobar 
 -------+------+--------
- (0,1) |    2 |      1
- (0,2) |    2 |      2
+ (0,1) |    1 |      1
+ (0,2) |    1 |      2
  (0,6) |   10 |    444
 (3 rows)
 
@@ -199,16 +99,16 @@ SAVEPOINT s1;
 SELECT ctid,cmin,* FROM combocidtest FOR UPDATE;
  ctid  | cmin | foobar 
 -------+------+--------
- (0,1) |    2 |      1
- (0,2) |    2 |      2
+ (0,1) |    1 |      1
+ (0,2) |    1 |      2
  (0,6) |   10 |    444
 (3 rows)
 
 SELECT ctid,cmin,* FROM combocidtest;
  ctid  | cmin | foobar 
 -------+------+--------
- (0,1) |    2 |      1
- (0,2) |    2 |      2
+ (0,1) |    1 |      1
+ (0,2) |    1 |      2
  (0,6) |   10 |    444
 (3 rows)
 
@@ -217,17 +117,17 @@ UPDATE combocidtest SET foobar = foobar + 10;
 SELECT ctid,cmin,* FROM combocidtest;
  ctid  | cmin | foobar 
 -------+------+--------
- (0,7) |   14 |     11
- (0,8) |   14 |     12
- (0,9) |   14 |    454
+ (0,7) |   12 |     11
+ (0,8) |   12 |     12
+ (0,9) |   12 |    454
 (3 rows)
 
 ROLLBACK TO s1;
 SELECT ctid,cmin,* FROM combocidtest;
  ctid  | cmin | foobar 
 -------+------+--------
- (0,1) |   14 |      1
- (0,2) |   14 |      2
+ (0,1) |   12 |      1
+ (0,2) |   12 |      2
  (0,6) |    0 |    444
 (3 rows)
 
@@ -235,8 +135,8 @@ COMMIT;
 SELECT ctid,cmin,* FROM combocidtest;
  ctid  | cmin | foobar 
 -------+------+--------
- (0,1) |   14 |      1
- (0,2) |   14 |      2
+ (0,1) |   12 |      1
+ (0,2) |   12 |      2
  (0,6) |    0 |    444
 (3 rows)
 
diff --git a/src/test/regress/sql/combocid.sql b/src/test/regress/sql/combocid.sql
index 3f30839b1f6..f24ac6b01a1 100644
--- a/src/test/regress/sql/combocid.sql
+++ b/src/test/regress/sql/combocid.sql
@@ -6,16 +6,16 @@ CREATE TEMP TABLE combocidtest (foobar int);
 BEGIN;
 
 -- a few dummy ops to push up the CommandId counter
-SELECT 1;
-SELECT 1;
-SELECT 1;
-SELECT 1;
-SELECT 1;
-SELECT 1;
-SELECT 1;
-SELECT 1;
-SELECT 1;
-SELECT 1;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
 
 INSERT INTO combocidtest VALUES (1);
 INSERT INTO combocidtest VALUES (2);
@@ -58,16 +58,16 @@ SELECT ctid,cmin,* FROM combocidtest;
 BEGIN;
 
 -- a few dummy ops to push up the CommandId counter
-SELECT 1;
-SELECT 1;
-SELECT 1;
-SELECT 1;
-SELECT 1;
-SELECT 1;
-SELECT 1;
-SELECT 1;
-SELECT 1;
-SELECT 1;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
+INSERT INTO combocidtest SELECT 1 LIMIT 0;
 
 INSERT INTO combocidtest VALUES (444);