citus/src/backend/distributed/executor/insert_select_executor.c

153 lines
4.7 KiB
C

/*-------------------------------------------------------------------------
*
* insert_select_executor.c
*
* Executor logic for INSERT..SELECT.
*
* Copyright (c) 2017, Citus Data, Inc.
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "distributed/insert_select_executor.h"
#include "distributed/insert_select_planner.h"
#include "distributed/multi_copy.h"
#include "distributed/multi_executor.h"
#include "distributed/multi_partitioning_utils.h"
#include "distributed/multi_physical_planner.h"
#include "distributed/distributed_planner.h"
#include "distributed/relation_access_tracking.h"
#include "distributed/resource_lock.h"
#include "distributed/transaction_management.h"
#include "executor/executor.h"
#include "nodes/execnodes.h"
#include "nodes/makefuncs.h"
#include "nodes/nodeFuncs.h"
#include "nodes/parsenodes.h"
#include "nodes/plannodes.h"
#include "parser/parse_coerce.h"
#include "parser/parsetree.h"
#include "tcop/pquery.h"
#include "tcop/tcopprot.h"
#include "utils/lsyscache.h"
#include "utils/portal.h"
#include "utils/snapmgr.h"
static void ExecuteSelectIntoRelation(Oid targetRelationId, List *insertTargetList,
Query *selectQuery, EState *executorState);
/*
* CoordinatorInsertSelectExecScan executes an INSERT INTO distributed_table
* SELECT .. query by setting up a DestReceiver that copies tuples into the
* distributed table and then executing the SELECT query using that DestReceiver
* as the tuple destination.
*/
TupleTableSlot *
CoordinatorInsertSelectExecScan(CustomScanState *node)
{
CitusScanState *scanState = (CitusScanState *) node;
TupleTableSlot *resultSlot = NULL;
if (!scanState->finishedRemoteScan)
{
EState *executorState = scanState->customScanState.ss.ps.state;
DistributedPlan *distributedPlan = scanState->distributedPlan;
Query *selectQuery = distributedPlan->insertSelectSubquery;
List *insertTargetList = distributedPlan->insertTargetList;
Oid targetRelationId = distributedPlan->targetRelationId;
ereport(DEBUG1, (errmsg("Collecting INSERT ... SELECT results on coordinator")));
/*
* If we are dealing with partitioned table, we also need to lock its
* partitions. Here we only lock targetRelation, we acquire necessary
* locks on selected tables during execution of those select queries.
*/
if (PartitionedTable(targetRelationId))
{
LockPartitionRelations(targetRelationId, RowExclusiveLock);
}
ExecuteSelectIntoRelation(targetRelationId, insertTargetList, selectQuery,
executorState);
scanState->finishedRemoteScan = true;
}
resultSlot = ReturnTupleFromTuplestore(scanState);
return resultSlot;
}
/*
* ExecuteSelectIntoRelation executes given SELECT query and inserts the
* results into the target relation, which is assumed to be a distributed
* table.
*/
static void
ExecuteSelectIntoRelation(Oid targetRelationId, List *insertTargetList,
Query *selectQuery, EState *executorState)
{
ParamListInfo paramListInfo = executorState->es_param_list_info;
ListCell *insertTargetCell = NULL;
List *columnNameList = NIL;
bool stopOnFailure = false;
char partitionMethod = 0;
Var *partitionColumn = NULL;
int partitionColumnIndex = -1;
CitusCopyDestReceiver *copyDest = NULL;
Query *queryCopy = NULL;
partitionMethod = PartitionMethod(targetRelationId);
if (partitionMethod == DISTRIBUTE_BY_NONE)
{
stopOnFailure = true;
}
partitionColumn = PartitionColumn(targetRelationId, 0);
/* build the list of column names for the COPY statement */
foreach(insertTargetCell, insertTargetList)
{
TargetEntry *insertTargetEntry = (TargetEntry *) lfirst(insertTargetCell);
char *columnName = insertTargetEntry->resname;
/* load the column information from pg_attribute */
AttrNumber attrNumber = get_attnum(targetRelationId, columnName);
/* check whether this is the partition column */
if (partitionColumn != NULL && attrNumber == partitionColumn->varattno)
{
Assert(partitionColumnIndex == -1);
partitionColumnIndex = list_length(columnNameList);
}
columnNameList = lappend(columnNameList, insertTargetEntry->resname);
}
/* set up a DestReceiver that copies into the distributed table */
copyDest = CreateCitusCopyDestReceiver(targetRelationId, columnNameList,
partitionColumnIndex, executorState,
stopOnFailure);
/*
* Make a copy of the query, since ExecuteQueryIntoDestReceiver may scribble on it
* and we want it to be replanned every time if it is stored in a prepared
* statement.
*/
queryCopy = copyObject(selectQuery);
ExecuteQueryIntoDestReceiver(queryCopy, paramListInfo, (DestReceiver *) copyDest);
executorState->es_processed = copyDest->tuplesSent;
XactModificationLevel = XACT_MODIFICATION_DATA;
}