Esempio n. 1
0
/*
 * Executes INSERT and DELETE DML operations. The
 * action is specified within the TupleTableSlot at
 * plannode->actionColIdx.The ctid of the tuple to delete
 * is in position plannode->ctidColIdx in the current slot.
 * */
TupleTableSlot*
ExecDML(DMLState *node)
{

	PlanState *outerNode = outerPlanState(node);
	DML *plannode = (DML *) node->ps.plan;

	Assert(outerNode != NULL);

	TupleTableSlot *slot = ExecProcNode(outerNode);

	if (TupIsNull(slot))
	{
		return NULL;
	}

	bool isnull = false;
	int action = DatumGetUInt32(slot_getattr(slot, plannode->actionColIdx, &isnull));

	Assert(!isnull);

	isnull = false;
	Datum oid = slot_getattr(slot, plannode->oidColIdx, &isnull);
	slot->tts_tableOid = DatumGetUInt32(oid);

	bool isUpdate = false;
	if (node->ps.state->es_plannedstmt->commandType == CMD_UPDATE)
	{
		isUpdate = true;
	}

	Assert(action == DML_INSERT || action == DML_DELETE);


	/*
	 * Reset per-tuple memory context to free any expression evaluation
	 * storage allocated in the previous tuple cycle.
	 */
	ExprContext *econtext = node->ps.ps_ExprContext;
	ResetExprContext(econtext);

	/* Prepare cleaned-up tuple by projecting it and filtering junk columns */
	econtext->ecxt_outertuple = slot;
	TupleTableSlot *projectedSlot = ExecProject(node->ps.ps_ProjInfo, NULL);

	/* remove 'junk' columns from tuple */
	node->cleanedUpSlot = ExecFilterJunk(node->junkfilter, projectedSlot);

	if (DML_INSERT == action)
	{

		/* Respect any given tuple Oid when updating a tuple. */
		if(isUpdate &&
		    plannode->tupleoidColIdx != 0)
		{
			isnull = false;
			oid = slot_getattr(slot, plannode->tupleoidColIdx, &isnull);
			HeapTuple htuple = ExecFetchSlotHeapTuple(node->cleanedUpSlot);
			Assert(htuple == node->cleanedUpSlot->PRIVATE_tts_heaptuple);
			HeapTupleSetOid(htuple, oid);
		}

		/* The plan origin is required since ExecInsert performs different actions 
		 * depending on the type of plan (constraint enforcement and triggers.) 
		 */
		ExecInsert(node->cleanedUpSlot, NULL /* destReceiver */,
				node->ps.state, PLANGEN_OPTIMIZER /* Plan origin */, 
				isUpdate);
	}
	else /* DML_DELETE */
	{
		Datum ctid = slot_getattr(slot, plannode->ctidColIdx, &isnull);

		Assert(!isnull);

		ItemPointer  tupleid = (ItemPointer) DatumGetPointer(ctid);
		ItemPointerData tuple_ctid = *tupleid;
		tupleid = &tuple_ctid;

		/* Correct tuple count by ignoring deletes when splitting tuples. */
		ExecDelete(tupleid, node->cleanedUpSlot, NULL /* DestReceiver */, node->ps.state,
				PLANGEN_OPTIMIZER /* Plan origin */, isUpdate);
	}

	return slot;
}
Esempio n. 2
0
/* ----------------------------------------------------------------
 *		ExecUpdate
 *
 *		note: we can't run UPDATE queries with transactions
 *		off because UPDATEs are actually INSERTs and our
 *		scan will mistakenly loop forever, updating the tuple
 *		it just inserted..	This should be fixed but until it
 *		is, we don't want to get stuck in an infinite loop
 *		which corrupts your database..
 * ----------------------------------------------------------------
 */
void
ExecUpdate(TupleTableSlot *slot,
		   ItemPointer tupleid,
		   TupleTableSlot *planSlot,
		   DestReceiver *dest,
		   EState *estate)
{
	HeapTuple	tuple;
	ResultRelInfo *resultRelInfo;
	Relation	resultRelationDesc;
	HTSU_Result result;
	ItemPointerData update_ctid;
	TransactionId update_xmax;

	/*
	 * abort the operation if not running transactions
	 */
	if (IsBootstrapProcessingMode())
		elog(ERROR, "cannot UPDATE during bootstrap");

	/*
	 * get the heap tuple out of the tuple table slot, making sure we have a
	 * writable copy
	 */
	tuple = ExecFetchSlotHeapTuple(slot);

	/*
	 * get information on the (current) result relation
	 */
	resultRelInfo = estate->es_result_relation_info;
	resultRelationDesc = resultRelInfo->ri_RelationDesc;

	/* see if this update would move the tuple to a different partition */
	if (estate->es_result_partitions)
	{
		AttrNumber max_attr;
		Datum *values;
		bool *nulls;
		Oid targetid;

		Assert(estate->es_partition_state != NULL &&
			   estate->es_partition_state->accessMethods != NULL);
		if (!estate->es_partition_state->accessMethods->part_cxt)
			estate->es_partition_state->accessMethods->part_cxt =
				GetPerTupleExprContext(estate)->ecxt_per_tuple_memory;

		Assert(PointerIsValid(estate->es_result_partitions));

		max_attr = estate->es_partition_state->max_partition_attr;

		slot_getsomeattrs(slot, max_attr);
		values = slot_get_values(slot);
		nulls = slot_get_isnull(slot);

		targetid = selectPartition(estate->es_result_partitions, values,
								   nulls, slot->tts_tupleDescriptor,
								   estate->es_partition_state->accessMethods);

		if (!OidIsValid(targetid))
			ereport(ERROR,
					(errcode(ERRCODE_NO_PARTITION_FOR_PARTITIONING_KEY),
					 errmsg("no partition for partitioning key")));

		if (RelationGetRelid(resultRelationDesc) != targetid)
		{
			ereport(ERROR,
					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
					 errmsg("moving tuple from partition \"%s\" to "
							"partition \"%s\" not supported",
							get_rel_name(RelationGetRelid(resultRelationDesc)),
							get_rel_name(targetid)),
					 errOmitLocation(true)));
		}
	}

	/* BEFORE ROW UPDATE Triggers */
	if (resultRelInfo->ri_TrigDesc &&
		resultRelInfo->ri_TrigDesc->n_before_row[TRIGGER_EVENT_UPDATE] > 0)
	{
		HeapTuple	newtuple;

		newtuple = ExecBRUpdateTriggers(estate, resultRelInfo,
										tupleid, tuple,
										estate->es_snapshot->curcid);

		if (newtuple == NULL)	/* "do nothing" */
			return;

		if (newtuple != tuple)	/* modified by Trigger(s) */
		{
			/*
			 * Put the modified tuple into a slot for convenience of routines
			 * below.  We assume the tuple was allocated in per-tuple memory
			 * context, and therefore will go away by itself. The tuple table
			 * slot should not try to clear it.
			 */
			TupleTableSlot *newslot = estate->es_trig_tuple_slot;

			if (newslot->tts_tupleDescriptor != slot->tts_tupleDescriptor)
				ExecSetSlotDescriptor(newslot, slot->tts_tupleDescriptor);
			ExecStoreGenericTuple(newtuple, newslot, false);
            newslot->tts_tableOid = slot->tts_tableOid; /* for constraints */
			slot = newslot;
			tuple = newtuple;
		}
	}

	/*
	 * Check the constraints of the tuple
	 *
	 * If we generate a new candidate tuple after EvalPlanQual testing, we
	 * must loop back here and recheck constraints.  (We don't need to redo
	 * triggers, however.  If there are any BEFORE triggers then trigger.c
	 * will have done heap_lock_tuple to lock the correct tuple, so there's no
	 * need to do them again.)
	 */
lreplace:;
	if (resultRelationDesc->rd_att->constr)
		ExecConstraints(resultRelInfo, slot, estate);

	if (!GpPersistent_IsPersistentRelation(resultRelationDesc->rd_id))
	{
		/*
		 * Normal UPDATE path.
		 */

		/*
		 * replace the heap tuple
		 *
		 * Note: if es_crosscheck_snapshot isn't InvalidSnapshot, we check that
		 * the row to be updated is visible to that snapshot, and throw a can't-
		 * serialize error if not.	This is a special-case behavior needed for
		 * referential integrity updates in serializable transactions.
		 */
		result = heap_update(resultRelationDesc, tupleid, tuple,
							 &update_ctid, &update_xmax,
							 estate->es_snapshot->curcid,
							 estate->es_crosscheck_snapshot,
							 true /* wait for commit */ );
		switch (result)
		{
			case HeapTupleSelfUpdated:
				/* already deleted by self; nothing to do */
				return;

			case HeapTupleMayBeUpdated:
				break;

			case HeapTupleUpdated:
				if (IsXactIsoLevelSerializable)
					ereport(ERROR,
							(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
							 errmsg("could not serialize access due to concurrent update")));
				else if (!ItemPointerEquals(tupleid, &update_ctid))
				{
					TupleTableSlot *epqslot;

					epqslot = EvalPlanQual(estate,
										   resultRelInfo->ri_RangeTableIndex,
										   &update_ctid,
										   update_xmax,
										   estate->es_snapshot->curcid);
					if (!TupIsNull(epqslot))
					{
						*tupleid = update_ctid;
						slot = ExecFilterJunk(estate->es_junkFilter, epqslot);
						tuple = ExecFetchSlotHeapTuple(slot);
						goto lreplace;
					}
				}
				/* tuple already deleted; nothing to do */
				return;

			default:
				elog(ERROR, "unrecognized heap_update status: %u", result);
				return;
		}
	}
	else
	{
		HeapTuple persistentTuple;

		/*
		 * Persistent metadata path.
		 */
		persistentTuple = heap_copytuple(tuple);
		persistentTuple->t_self = *tupleid;

		frozen_heap_inplace_update(resultRelationDesc, persistentTuple);

		heap_freetuple(persistentTuple);
	}

	IncrReplaced();
	(estate->es_processed)++;

	/*
	 * Note: instead of having to update the old index tuples associated with
	 * the heap tuple, all we do is form and insert new index tuples. This is
	 * because UPDATEs are actually DELETEs and INSERTs, and index tuple
	 * deletion is done later by VACUUM (see notes in ExecDelete).	All we do
	 * here is insert new index tuples.  -cim 9/27/89
	 */
	/*
	 * insert index entries for tuple
	 *
	 * Note: heap_update returns the tid (location) of the new tuple in the
	 * t_self field.
	 */
	if (resultRelInfo->ri_NumIndices > 0)
		ExecInsertIndexTuples(slot, &(tuple->t_self), estate, false);

	/* AFTER ROW UPDATE Triggers */
	ExecARUpdateTriggers(estate, resultRelInfo, tupleid, tuple);

}
Esempio n. 3
0
/* ----------------------------------------------------------------
 *		ExecUpdate
 *
 *		note: we can't run UPDATE queries with transactions
 *		off because UPDATEs are actually INSERTs and our
 *		scan will mistakenly loop forever, updating the tuple
 *		it just inserted..	This should be fixed but until it
 *		is, we don't want to get stuck in an infinite loop
 *		which corrupts your database..
 * ----------------------------------------------------------------
 */
void
ExecUpdate(TupleTableSlot *slot,
		   ItemPointer tupleid,
		   TupleTableSlot *planSlot,
		   DestReceiver *dest,
		   EState *estate)
{
	void*	tuple;
	ResultRelInfo *resultRelInfo;
	Relation	resultRelationDesc;
	HTSU_Result result;
	ItemPointerData update_ctid;
	TransactionId update_xmax;
	AOTupleId	aoTupleId = AOTUPLEID_INIT;
	TupleTableSlot *partslot = NULL;

	/*
	 * abort the operation if not running transactions
	 */
	if (IsBootstrapProcessingMode())
		elog(ERROR, "cannot UPDATE during bootstrap");
	
	/*
	 * get information on the (current) result relation
	 */
	resultRelInfo = estate->es_result_relation_info;
	resultRelationDesc = resultRelInfo->ri_RelationDesc;

	bool		rel_is_heap = RelationIsHeap(resultRelationDesc);
	bool 		rel_is_aorows = RelationIsAoRows(resultRelationDesc);
	bool		rel_is_aocols = RelationIsAoCols(resultRelationDesc);
	bool		rel_is_external = RelationIsExternal(resultRelationDesc);

	/*
	 * get the heap tuple out of the tuple table slot, making sure we have a
	 * writable copy
	 */
	if (rel_is_heap)
	{
		partslot = slot;
		tuple = ExecFetchSlotHeapTuple(partslot);
	}
	else if (rel_is_aorows || rel_is_aocols)
	{
		/*
		 * It is necessary to reconstruct a logically compatible tuple to
		 * a phyiscally compatible tuple.  The slot's tuple descriptor comes
		 * from the projection target list, which doesn't indicate dropped
		 * columns, and MemTuple cannot deal with cases without converting
		 * the target list back into the original relation's tuple desc.
		 */
		partslot = reconstructMatchingTupleSlot(slot, resultRelInfo);

		/*
		 * We directly inline toasted columns here as update with toasted columns
		 * would create two references to the same toasted value.
		 */
		tuple = ExecFetchSlotMemTuple(partslot, true);
	}
	else if (rel_is_external) 
	{
		if (estate->es_result_partitions && 
			estate->es_result_partitions->part->parrelid != 0)
		{
			ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				errmsg("Update external partitions not supported.")));			
			return;
		}
		else
		{
			partslot = slot;
			tuple = ExecFetchSlotHeapTuple(partslot);
		}
	}
	else 
	{
		Insist(false);
	}

	/* see if this update would move the tuple to a different partition */
	if (estate->es_result_partitions)
		checkPartitionUpdate(estate, partslot, resultRelInfo);

	/* BEFORE ROW UPDATE Triggers */
	if (resultRelInfo->ri_TrigDesc &&
		resultRelInfo->ri_TrigDesc->n_before_row[TRIGGER_EVENT_UPDATE] > 0)
	{
		HeapTuple	newtuple;

		newtuple = ExecBRUpdateTriggers(estate, resultRelInfo,
										tupleid, tuple,
										estate->es_snapshot->curcid);

		if (newtuple == NULL)	/* "do nothing" */
			return;

		if (newtuple != tuple)	/* modified by Trigger(s) */
		{
			/*
			 * Put the modified tuple into a slot for convenience of routines
			 * below.  We assume the tuple was allocated in per-tuple memory
			 * context, and therefore will go away by itself. The tuple table
			 * slot should not try to clear it.
			 */
			TupleTableSlot *newslot = estate->es_trig_tuple_slot;

			if (newslot->tts_tupleDescriptor != partslot->tts_tupleDescriptor)
				ExecSetSlotDescriptor(newslot, partslot->tts_tupleDescriptor);
			ExecStoreGenericTuple(newtuple, newslot, false);
            newslot->tts_tableOid = partslot->tts_tableOid; /* for constraints */
			partslot = newslot;
			tuple = newtuple;
		}
	}

	/*
	 * Check the constraints of the tuple
	 *
	 * If we generate a new candidate tuple after EvalPlanQual testing, we
	 * must loop back here and recheck constraints.  (We don't need to redo
	 * triggers, however.  If there are any BEFORE triggers then trigger.c
	 * will have done heap_lock_tuple to lock the correct tuple, so there's no
	 * need to do them again.)
	 */
lreplace:;
	if (resultRelationDesc->rd_att->constr)
		ExecConstraints(resultRelInfo, partslot, estate);

	if (!GpPersistent_IsPersistentRelation(resultRelationDesc->rd_id))
	{
		/*
		 * Normal UPDATE path.
		 */

		/*
		 * replace the heap tuple
		 *
		 * Note: if es_crosscheck_snapshot isn't InvalidSnapshot, we check that
		 * the row to be updated is visible to that snapshot, and throw a can't-
		 * serialize error if not.	This is a special-case behavior needed for
		 * referential integrity updates in serializable transactions.
		 */
		if (rel_is_heap)
		{
			result = heap_update(resultRelationDesc, tupleid, tuple,
							 &update_ctid, &update_xmax,
							 estate->es_snapshot->curcid,
							 estate->es_crosscheck_snapshot,
							 true /* wait for commit */ );
		} 
		else if (rel_is_aorows)
		{
			if (IsXactIsoLevelSerializable)
			{
				ereport(ERROR,
					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
					errmsg("Updates on append-only tables are not supported in serializable transactions.")));			
			}

			if (resultRelInfo->ri_updateDesc == NULL)
			{
				ResultRelInfoSetSegno(resultRelInfo, estate->es_result_aosegnos);
				resultRelInfo->ri_updateDesc = (AppendOnlyUpdateDesc)
					appendonly_update_init(resultRelationDesc, ActiveSnapshot, resultRelInfo->ri_aosegno);
			}
			result = appendonly_update(resultRelInfo->ri_updateDesc,
								 tuple, (AOTupleId *) tupleid, &aoTupleId);
		}
		else if (rel_is_aocols)
		{
			if (IsXactIsoLevelSerializable)
			{
				ereport(ERROR,
					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
					errmsg("Updates on append-only tables are not supported in serializable transactions.")));			
			}

			if (resultRelInfo->ri_updateDesc == NULL)
			{
				ResultRelInfoSetSegno(resultRelInfo, estate->es_result_aosegnos);
				resultRelInfo->ri_updateDesc = (AppendOnlyUpdateDesc)
					aocs_update_init(resultRelationDesc, resultRelInfo->ri_aosegno);
			}
			result = aocs_update(resultRelInfo->ri_updateDesc,
								 partslot, (AOTupleId *) tupleid, &aoTupleId);
		}
		else
		{
			Assert(!"We should not be here");
		}
		switch (result)
		{
			case HeapTupleSelfUpdated:
				/* already deleted by self; nothing to do */
				return;

			case HeapTupleMayBeUpdated:
				break;

			case HeapTupleUpdated:
				if (IsXactIsoLevelSerializable)
					ereport(ERROR,
							(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
							 errmsg("could not serialize access due to concurrent update")));
				else if (!ItemPointerEquals(tupleid, &update_ctid))
				{
					TupleTableSlot *epqslot;

					epqslot = EvalPlanQual(estate,
										   resultRelInfo->ri_RangeTableIndex,
										   &update_ctid,
										   update_xmax,
										   estate->es_snapshot->curcid);
					if (!TupIsNull(epqslot))
					{
						*tupleid = update_ctid;
						partslot = ExecFilterJunk(estate->es_junkFilter, epqslot);
						tuple = ExecFetchSlotHeapTuple(partslot);
						goto lreplace;
					}
				}
				/* tuple already deleted; nothing to do */
				return;

			default:
				elog(ERROR, "unrecognized heap_update status: %u", result);
				return;
		}
	}
	else
	{
		HeapTuple persistentTuple;

		/*
		 * Persistent metadata path.
		 */
		persistentTuple = heap_copytuple(tuple);
		persistentTuple->t_self = *tupleid;

		frozen_heap_inplace_update(resultRelationDesc, persistentTuple);

		heap_freetuple(persistentTuple);
	}

	IncrReplaced();
	(estate->es_processed)++;
	(resultRelInfo->ri_aoprocessed)++;

	/*
	 * Note: instead of having to update the old index tuples associated with
	 * the heap tuple, all we do is form and insert new index tuples. This is
	 * because UPDATEs are actually DELETEs and INSERTs, and index tuple
	 * deletion is done later by VACUUM (see notes in ExecDelete).	All we do
	 * here is insert new index tuples.  -cim 9/27/89
	 */
	/*
	 * insert index entries for tuple
	 *
	 * Note: heap_update returns the tid (location) of the new tuple in the
	 * t_self field.
	 */
	if (rel_is_aorows || rel_is_aocols)
	{
		if (resultRelInfo->ri_NumIndices > 0)
			ExecInsertIndexTuples(partslot, (ItemPointer)&aoTupleId, estate, false);
	}
	else
	{
		if (resultRelInfo->ri_NumIndices > 0)
			ExecInsertIndexTuples(partslot, &(((HeapTuple) tuple)->t_self), estate, false);
	}

	/* AFTER ROW UPDATE Triggers */
	ExecARUpdateTriggers(estate, resultRelInfo, tupleid, tuple);

}