mirror of https://github.com/citusdata/citus.git
323 lines
9.0 KiB
C
323 lines
9.0 KiB
C
/*-------------------------------------------------------------------------
|
|
*
|
|
* multi_executor.c
|
|
*
|
|
* Entrypoint into distributed query execution.
|
|
*
|
|
* Copyright (c) 2012-2016, Citus Data, Inc.
|
|
*-------------------------------------------------------------------------
|
|
*/
|
|
|
|
#include "postgres.h"
|
|
|
|
#include "miscadmin.h"
|
|
|
|
#include "access/xact.h"
|
|
#include "catalog/dependency.h"
|
|
#include "catalog/namespace.h"
|
|
#include "distributed/citus_custom_scan.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_master_planner.h"
|
|
#include "distributed/distributed_planner.h"
|
|
#include "distributed/multi_router_executor.h"
|
|
#include "distributed/multi_router_planner.h"
|
|
#include "distributed/multi_resowner.h"
|
|
#include "distributed/multi_server_executor.h"
|
|
#include "distributed/multi_utility.h"
|
|
#include "distributed/resource_lock.h"
|
|
#include "distributed/worker_protocol.h"
|
|
#include "executor/execdebug.h"
|
|
#include "commands/copy.h"
|
|
#include "nodes/makefuncs.h"
|
|
#include "parser/parsetree.h"
|
|
#include "storage/lmgr.h"
|
|
#include "tcop/pquery.h"
|
|
#include "tcop/utility.h"
|
|
#include "utils/snapmgr.h"
|
|
#include "utils/memutils.h"
|
|
|
|
|
|
/* controls the connection type for multi shard update/delete queries */
|
|
int MultiShardConnectionType = PARALLEL_CONNECTION;
|
|
|
|
|
|
/* ocal function forward declarations */
|
|
static Relation StubRelation(TupleDesc tupleDescriptor);
|
|
|
|
|
|
/*
|
|
* ReturnTupleFromTuplestore reads the next tuple from the tuple store of the
|
|
* given Citus scan node and returns it. It returns null if all tuples are read
|
|
* from the tuple store.
|
|
*/
|
|
TupleTableSlot *
|
|
ReturnTupleFromTuplestore(CitusScanState *scanState)
|
|
{
|
|
Tuplestorestate *tupleStore = scanState->tuplestorestate;
|
|
TupleTableSlot *resultSlot = NULL;
|
|
ScanDirection scanDirection = NoMovementScanDirection;
|
|
bool forwardScanDirection = true;
|
|
|
|
if (tupleStore == NULL)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
scanDirection = scanState->customScanState.ss.ps.state->es_direction;
|
|
Assert(ScanDirectionIsValid(scanDirection));
|
|
|
|
if (ScanDirectionIsBackward(scanDirection))
|
|
{
|
|
forwardScanDirection = false;
|
|
}
|
|
|
|
resultSlot = scanState->customScanState.ss.ps.ps_ResultTupleSlot;
|
|
tuplestore_gettupleslot(tupleStore, forwardScanDirection, false, resultSlot);
|
|
|
|
return resultSlot;
|
|
}
|
|
|
|
|
|
/*
|
|
* Load data collected by real-time or task-tracker executors into the tuplestore
|
|
* of CitusScanState. For that, we first create a tuple store, and then copy the
|
|
* files one-by-one into the tuple store.
|
|
*
|
|
* Note that in the long term it'd be a lot better if Multi*Execute() directly
|
|
* filled the tuplestores, but that's a fair bit of work.
|
|
*/
|
|
void
|
|
LoadTuplesIntoTupleStore(CitusScanState *citusScanState, Job *workerJob)
|
|
{
|
|
CustomScanState customScanState = citusScanState->customScanState;
|
|
List *workerTaskList = workerJob->taskList;
|
|
TupleDesc tupleDescriptor = NULL;
|
|
ListCell *workerTaskCell = NULL;
|
|
bool randomAccess = true;
|
|
bool interTransactions = false;
|
|
char *copyFormat = "text";
|
|
|
|
tupleDescriptor = customScanState.ss.ps.ps_ResultTupleSlot->tts_tupleDescriptor;
|
|
|
|
Assert(citusScanState->tuplestorestate == NULL);
|
|
citusScanState->tuplestorestate =
|
|
tuplestore_begin_heap(randomAccess, interTransactions, work_mem);
|
|
|
|
if (BinaryMasterCopyFormat)
|
|
{
|
|
copyFormat = "binary";
|
|
}
|
|
|
|
foreach(workerTaskCell, workerTaskList)
|
|
{
|
|
Task *workerTask = (Task *) lfirst(workerTaskCell);
|
|
StringInfo jobDirectoryName = NULL;
|
|
StringInfo taskFilename = NULL;
|
|
|
|
jobDirectoryName = MasterJobDirectoryName(workerTask->jobId);
|
|
taskFilename = TaskFilename(jobDirectoryName, workerTask->taskId);
|
|
|
|
ReadFileIntoTupleStore(taskFilename->data, copyFormat, tupleDescriptor,
|
|
citusScanState->tuplestorestate);
|
|
}
|
|
|
|
tuplestore_donestoring(citusScanState->tuplestorestate);
|
|
}
|
|
|
|
|
|
/*
|
|
* ReadFileIntoTupleStore parses the records in a COPY-formatted file according
|
|
* according to the given tuple descriptor and stores the records in a tuple
|
|
* store.
|
|
*/
|
|
void
|
|
ReadFileIntoTupleStore(char *fileName, char *copyFormat, TupleDesc tupleDescriptor,
|
|
Tuplestorestate *tupstore)
|
|
{
|
|
CopyState copyState = NULL;
|
|
|
|
/*
|
|
* Trick BeginCopyFrom into using our tuple descriptor by pretending it belongs
|
|
* to a relation.
|
|
*/
|
|
Relation stubRelation = StubRelation(tupleDescriptor);
|
|
|
|
EState *executorState = CreateExecutorState();
|
|
MemoryContext executorTupleContext = GetPerTupleMemoryContext(executorState);
|
|
ExprContext *executorExpressionContext = GetPerTupleExprContext(executorState);
|
|
MemoryContext oldContext = NULL;
|
|
|
|
int columnCount = tupleDescriptor->natts;
|
|
Datum *columnValues = palloc0(columnCount * sizeof(Datum));
|
|
bool *columnNulls = palloc0(columnCount * sizeof(bool));
|
|
|
|
DefElem *copyOption = NULL;
|
|
List *copyOptions = NIL;
|
|
|
|
#if (PG_VERSION_NUM >= 100000)
|
|
int location = -1; /* "unknown" token location */
|
|
copyOption = makeDefElem("format", (Node *) makeString(copyFormat), location);
|
|
#else
|
|
copyOption = makeDefElem("format", (Node *) makeString(copyFormat));
|
|
#endif
|
|
copyOptions = lappend(copyOptions, copyOption);
|
|
|
|
PG_TRY();
|
|
{
|
|
#if (PG_VERSION_NUM >= 100000)
|
|
copyState = BeginCopyFrom(NULL, stubRelation, fileName, false, NULL,
|
|
NULL, copyOptions);
|
|
#else
|
|
copyState = BeginCopyFrom(stubRelation, fileName, false, NULL,
|
|
copyOptions);
|
|
#endif
|
|
|
|
while (true)
|
|
{
|
|
bool nextRowFound = false;
|
|
|
|
ResetPerTupleExprContext(executorState);
|
|
oldContext = MemoryContextSwitchTo(executorTupleContext);
|
|
|
|
nextRowFound = NextCopyFrom(copyState, executorExpressionContext,
|
|
columnValues, columnNulls, NULL);
|
|
if (!nextRowFound)
|
|
{
|
|
MemoryContextSwitchTo(oldContext);
|
|
break;
|
|
}
|
|
|
|
tuplestore_putvalues(tupstore, tupleDescriptor, columnValues, columnNulls);
|
|
MemoryContextSwitchTo(oldContext);
|
|
}
|
|
}
|
|
PG_CATCH();
|
|
{
|
|
if (oldContext != NULL)
|
|
{
|
|
MemoryContextSwitchTo(oldContext);
|
|
}
|
|
|
|
/*
|
|
* This is only necessary on windows, in the abort handler we might try to remove
|
|
* the file being COPY'd (if it was an intermediate result), but on Windows that's
|
|
* not possible unless we first close our handle to the file.
|
|
*
|
|
* This was already going to be called during abort, but it was going to be called
|
|
* after we try to delete the file, we need it to be called before.
|
|
*/
|
|
AtEOXact_Files();
|
|
|
|
PG_RE_THROW();
|
|
}
|
|
PG_END_TRY();
|
|
|
|
EndCopyFrom(copyState);
|
|
pfree(columnValues);
|
|
pfree(columnNulls);
|
|
}
|
|
|
|
|
|
/*
|
|
* StubRelation creates a stub Relation from the given tuple descriptor.
|
|
* To be able to use copy.c, we need a Relation descriptor. As there is no
|
|
* relation corresponding to the data loaded from workers, we need to fake one.
|
|
* We just need the bare minimal set of fields accessed by BeginCopyFrom().
|
|
*/
|
|
static Relation
|
|
StubRelation(TupleDesc tupleDescriptor)
|
|
{
|
|
Relation stubRelation = palloc0(sizeof(RelationData));
|
|
stubRelation->rd_att = tupleDescriptor;
|
|
stubRelation->rd_rel = palloc0(sizeof(FormData_pg_class));
|
|
stubRelation->rd_rel->relkind = RELKIND_RELATION;
|
|
|
|
return stubRelation;
|
|
}
|
|
|
|
|
|
/*
|
|
* ExecuteQueryStringIntoDestReceiver plans and executes a query and sends results
|
|
* to the given DestReceiver.
|
|
*/
|
|
void
|
|
ExecuteQueryStringIntoDestReceiver(const char *queryString, ParamListInfo params,
|
|
DestReceiver *dest)
|
|
{
|
|
Query *query = NULL;
|
|
|
|
#if (PG_VERSION_NUM >= 100000)
|
|
RawStmt *rawStmt = (RawStmt *) ParseTreeRawStmt(queryString);
|
|
List *queryTreeList = pg_analyze_and_rewrite(rawStmt, queryString, NULL, 0, NULL);
|
|
#else
|
|
Node *queryTreeNode = ParseTreeNode(queryString);
|
|
List *queryTreeList = pg_analyze_and_rewrite(queryTreeNode, queryString, NULL, 0);
|
|
#endif
|
|
|
|
if (list_length(queryTreeList) != 1)
|
|
{
|
|
ereport(ERROR, (errmsg("can only execute a single query")));
|
|
}
|
|
|
|
query = (Query *) linitial(queryTreeList);
|
|
|
|
ExecuteQueryIntoDestReceiver(query, params, dest);
|
|
}
|
|
|
|
|
|
/*
|
|
* ExecuteQueryIntoDestReceiver plans and executes a query and sends results to the given
|
|
* DestReceiver.
|
|
*/
|
|
void
|
|
ExecuteQueryIntoDestReceiver(Query *query, ParamListInfo params, DestReceiver *dest)
|
|
{
|
|
PlannedStmt *queryPlan = NULL;
|
|
int cursorOptions = 0;
|
|
|
|
cursorOptions = CURSOR_OPT_PARALLEL_OK;
|
|
|
|
/* plan the subquery, this may be another distributed query */
|
|
queryPlan = pg_plan_query(query, cursorOptions, params);
|
|
|
|
ExecutePlanIntoDestReceiver(queryPlan, params, dest);
|
|
}
|
|
|
|
|
|
/*
|
|
* ExecuteIntoDestReceiver plans and executes a query and sends results to the given
|
|
* DestReceiver.
|
|
*/
|
|
void
|
|
ExecutePlanIntoDestReceiver(PlannedStmt *queryPlan, ParamListInfo params,
|
|
DestReceiver *dest)
|
|
{
|
|
Portal portal = NULL;
|
|
int eflags = 0;
|
|
long count = FETCH_ALL;
|
|
|
|
/* create a new portal for executing the query */
|
|
portal = CreateNewPortal();
|
|
|
|
/* don't display the portal in pg_cursors, it is for internal use only */
|
|
portal->visible = false;
|
|
|
|
PortalDefineQuery(portal,
|
|
NULL,
|
|
"",
|
|
"SELECT",
|
|
list_make1(queryPlan),
|
|
NULL);
|
|
|
|
PortalStart(portal, params, eflags, GetActiveSnapshot());
|
|
#if (PG_VERSION_NUM >= 100000)
|
|
PortalRun(portal, count, false, true, dest, dest, NULL);
|
|
#else
|
|
PortalRun(portal, count, false, dest, dest, NULL);
|
|
#endif
|
|
PortalDrop(portal, false);
|
|
}
|