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92288a1cf9
o Change all current CVS messages of NOTICE to WARNING. We were going to do this just before 7.3 beta but it has to be done now, as you will see below. o Change current INFO messages that should be controlled by client_min_messages to NOTICE. o Force remaining INFO messages, like from EXPLAIN, VACUUM VERBOSE, etc. to always go to the client. o Remove INFO from the client_min_messages options and add NOTICE. Seems we do need three non-ERROR elog levels to handle the various behaviors we need for these messages. Regression passed.
1927 lines
49 KiB
C
1927 lines
49 KiB
C
/*-------------------------------------------------------------------------
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*
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* execMain.c
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* top level executor interface routines
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*
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* INTERFACE ROUTINES
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* ExecutorStart()
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* ExecutorRun()
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* ExecutorEnd()
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*
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* The old ExecutorMain() has been replaced by ExecutorStart(),
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* ExecutorRun() and ExecutorEnd()
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*
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* These three procedures are the external interfaces to the executor.
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* In each case, the query descriptor and the execution state is required
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* as arguments
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*
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* ExecutorStart() must be called at the beginning of any execution of any
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* query plan and ExecutorEnd() should always be called at the end of
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* execution of a plan.
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*
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* ExecutorRun accepts direction and count arguments that specify whether
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* the plan is to be executed forwards, backwards, and for how many tuples.
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*
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* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/executor/execMain.c,v 1.152 2002/03/06 06:09:42 momjian Exp $
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include "access/heapam.h"
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#include "catalog/heap.h"
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#include "commands/command.h"
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#include "commands/trigger.h"
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#include "executor/execdebug.h"
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#include "executor/execdefs.h"
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#include "miscadmin.h"
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#include "optimizer/var.h"
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#include "parser/parsetree.h"
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#include "utils/acl.h"
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/* decls for local routines only used within this module */
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static TupleDesc InitPlan(CmdType operation,
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Query *parseTree,
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Plan *plan,
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EState *estate);
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static void initResultRelInfo(ResultRelInfo *resultRelInfo,
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Index resultRelationIndex,
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List *rangeTable,
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CmdType operation);
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static void EndPlan(Plan *plan, EState *estate);
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static TupleTableSlot *ExecutePlan(EState *estate, Plan *plan,
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CmdType operation,
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long numberTuples,
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ScanDirection direction,
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DestReceiver *destfunc);
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static void ExecRetrieve(TupleTableSlot *slot,
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DestReceiver *destfunc,
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EState *estate);
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static void ExecAppend(TupleTableSlot *slot, ItemPointer tupleid,
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EState *estate);
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static void ExecDelete(TupleTableSlot *slot, ItemPointer tupleid,
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EState *estate);
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static void ExecReplace(TupleTableSlot *slot, ItemPointer tupleid,
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EState *estate);
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static TupleTableSlot *EvalPlanQualNext(EState *estate);
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static void EndEvalPlanQual(EState *estate);
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static void ExecCheckQueryPerms(CmdType operation, Query *parseTree,
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Plan *plan);
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static void ExecCheckPlanPerms(Plan *plan, List *rangeTable,
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CmdType operation);
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static void ExecCheckRTPerms(List *rangeTable, CmdType operation);
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static void ExecCheckRTEPerms(RangeTblEntry *rte, CmdType operation);
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/* end of local decls */
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/* ----------------------------------------------------------------
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* ExecutorStart
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*
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* This routine must be called at the beginning of any execution of any
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* query plan
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*
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* returns a TupleDesc which describes the attributes of the tuples to
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* be returned by the query. (Same value is saved in queryDesc)
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*
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* NB: the CurrentMemoryContext when this is called must be the context
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* to be used as the per-query context for the query plan. ExecutorRun()
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* and ExecutorEnd() must be called in this same memory context.
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* ----------------------------------------------------------------
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*/
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TupleDesc
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ExecutorStart(QueryDesc *queryDesc, EState *estate)
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{
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TupleDesc result;
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/* sanity checks */
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Assert(queryDesc != NULL);
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if (queryDesc->plantree->nParamExec > 0)
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{
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estate->es_param_exec_vals = (ParamExecData *)
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palloc(queryDesc->plantree->nParamExec * sizeof(ParamExecData));
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MemSet(estate->es_param_exec_vals, 0,
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queryDesc->plantree->nParamExec * sizeof(ParamExecData));
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}
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/*
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* Make our own private copy of the current queries snapshot data
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*/
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if (QuerySnapshot == NULL)
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estate->es_snapshot = NULL;
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else
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{
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estate->es_snapshot = (Snapshot) palloc(sizeof(SnapshotData));
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memcpy(estate->es_snapshot, QuerySnapshot, sizeof(SnapshotData));
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if (estate->es_snapshot->xcnt > 0)
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{
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estate->es_snapshot->xip = (TransactionId *)
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palloc(estate->es_snapshot->xcnt * sizeof(TransactionId));
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memcpy(estate->es_snapshot->xip, QuerySnapshot->xip,
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estate->es_snapshot->xcnt * sizeof(TransactionId));
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}
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}
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/*
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* Initialize the plan
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*/
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result = InitPlan(queryDesc->operation,
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queryDesc->parsetree,
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queryDesc->plantree,
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estate);
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queryDesc->tupDesc = result;
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return result;
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}
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/* ----------------------------------------------------------------
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* ExecutorRun
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*
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* This is the main routine of the executor module. It accepts
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* the query descriptor from the traffic cop and executes the
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* query plan.
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*
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* ExecutorStart must have been called already.
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*
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* If direction is NoMovementScanDirection then nothing is done
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* except to start up/shut down the destination. Otherwise,
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* we retrieve up to 'count' tuples in the specified direction.
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*
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* Note: count = 0 is interpreted as "no limit".
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*
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* ----------------------------------------------------------------
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*/
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TupleTableSlot *
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ExecutorRun(QueryDesc *queryDesc, EState *estate,
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ScanDirection direction, long count)
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{
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CmdType operation;
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Plan *plan;
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CommandDest dest;
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DestReceiver *destfunc;
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TupleTableSlot *result;
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/*
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* sanity checks
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*/
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Assert(queryDesc != NULL);
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/*
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* extract information from the query descriptor and the query
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* feature.
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*/
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operation = queryDesc->operation;
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plan = queryDesc->plantree;
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dest = queryDesc->dest;
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/*
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* startup tuple receiver
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*/
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estate->es_processed = 0;
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estate->es_lastoid = InvalidOid;
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destfunc = DestToFunction(dest);
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(*destfunc->setup) (destfunc, (int) operation,
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queryDesc->portalName, queryDesc->tupDesc);
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/*
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* run plan
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*/
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if (direction == NoMovementScanDirection)
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result = NULL;
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else
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result = ExecutePlan(estate,
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plan,
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operation,
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count,
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direction,
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destfunc);
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/*
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* shutdown receiver
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*/
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(*destfunc->cleanup) (destfunc);
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return result;
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}
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/* ----------------------------------------------------------------
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* ExecutorEnd
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*
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* This routine must be called at the end of execution of any
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* query plan
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* ----------------------------------------------------------------
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*/
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void
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ExecutorEnd(QueryDesc *queryDesc, EState *estate)
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{
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/* sanity checks */
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Assert(queryDesc != NULL);
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EndPlan(queryDesc->plantree, estate);
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if (estate->es_snapshot != NULL)
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{
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if (estate->es_snapshot->xcnt > 0)
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pfree(estate->es_snapshot->xip);
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pfree(estate->es_snapshot);
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estate->es_snapshot = NULL;
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}
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if (estate->es_param_exec_vals != NULL)
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{
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pfree(estate->es_param_exec_vals);
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estate->es_param_exec_vals = NULL;
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}
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}
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/*
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* ExecCheckQueryPerms
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* Check access permissions for all relations referenced in a query.
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*/
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static void
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ExecCheckQueryPerms(CmdType operation, Query *parseTree, Plan *plan)
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{
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/*
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* Check RTEs in the query's primary rangetable.
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*/
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ExecCheckRTPerms(parseTree->rtable, operation);
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/*
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* Search for subplans and APPEND nodes to check their rangetables.
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*/
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ExecCheckPlanPerms(plan, parseTree->rtable, operation);
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}
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/*
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* ExecCheckPlanPerms
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* Recursively scan the plan tree to check access permissions in
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* subplans.
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*/
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static void
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ExecCheckPlanPerms(Plan *plan, List *rangeTable, CmdType operation)
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{
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List *subp;
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if (plan == NULL)
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return;
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/* Check subplans, which we assume are plain SELECT queries */
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foreach(subp, plan->initPlan)
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{
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SubPlan *subplan = (SubPlan *) lfirst(subp);
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ExecCheckRTPerms(subplan->rtable, CMD_SELECT);
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ExecCheckPlanPerms(subplan->plan, subplan->rtable, CMD_SELECT);
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}
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foreach(subp, plan->subPlan)
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{
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SubPlan *subplan = (SubPlan *) lfirst(subp);
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ExecCheckRTPerms(subplan->rtable, CMD_SELECT);
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ExecCheckPlanPerms(subplan->plan, subplan->rtable, CMD_SELECT);
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}
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/* Check lower plan nodes */
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ExecCheckPlanPerms(plan->lefttree, rangeTable, operation);
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ExecCheckPlanPerms(plan->righttree, rangeTable, operation);
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/* Do node-type-specific checks */
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switch (nodeTag(plan))
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{
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case T_SubqueryScan:
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{
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SubqueryScan *scan = (SubqueryScan *) plan;
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RangeTblEntry *rte;
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/* Recursively check the subquery */
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rte = rt_fetch(scan->scan.scanrelid, rangeTable);
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Assert(rte->subquery != NULL);
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ExecCheckQueryPerms(operation, rte->subquery, scan->subplan);
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break;
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}
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case T_Append:
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{
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Append *app = (Append *) plan;
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List *appendplans;
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foreach(appendplans, app->appendplans)
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{
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ExecCheckPlanPerms((Plan *) lfirst(appendplans),
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rangeTable,
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operation);
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}
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break;
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}
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default:
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break;
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}
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}
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/*
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* ExecCheckRTPerms
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* Check access permissions for all relations listed in a range table.
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*/
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static void
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ExecCheckRTPerms(List *rangeTable, CmdType operation)
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{
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List *lp;
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foreach(lp, rangeTable)
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{
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RangeTblEntry *rte = lfirst(lp);
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ExecCheckRTEPerms(rte, operation);
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}
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}
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/*
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* ExecCheckRTEPerms
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* Check access permissions for a single RTE.
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*/
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static void
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ExecCheckRTEPerms(RangeTblEntry *rte, CmdType operation)
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{
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char *relName;
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Oid userid;
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int32 aclcheck_result;
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/*
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* If it's a subquery RTE, ignore it --- it will be checked when
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* ExecCheckPlanPerms finds the SubqueryScan node for it.
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*/
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if (rte->subquery)
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return;
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relName = rte->relname;
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/*
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* userid to check as: current user unless we have a setuid
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* indication.
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*
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* Note: GetUserId() is presently fast enough that there's no harm in
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* calling it separately for each RTE. If that stops being true, we
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* could call it once in ExecCheckQueryPerms and pass the userid down
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* from there. But for now, no need for the extra clutter.
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*/
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userid = rte->checkAsUser ? rte->checkAsUser : GetUserId();
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#define CHECK(MODE) pg_aclcheck(relName, userid, MODE)
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if (rte->checkForRead)
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{
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aclcheck_result = CHECK(ACL_SELECT);
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if (aclcheck_result != ACLCHECK_OK)
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elog(ERROR, "%s: %s",
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relName, aclcheck_error_strings[aclcheck_result]);
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}
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if (rte->checkForWrite)
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{
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/*
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* Note: write access in a SELECT context means SELECT FOR UPDATE.
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* Right now we don't distinguish that from true update as far as
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* permissions checks are concerned.
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*/
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switch (operation)
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{
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case CMD_INSERT:
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aclcheck_result = CHECK(ACL_INSERT);
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break;
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case CMD_SELECT:
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case CMD_UPDATE:
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aclcheck_result = CHECK(ACL_UPDATE);
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break;
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case CMD_DELETE:
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aclcheck_result = CHECK(ACL_DELETE);
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break;
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default:
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elog(ERROR, "ExecCheckRTEPerms: bogus operation %d",
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operation);
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aclcheck_result = ACLCHECK_OK; /* keep compiler quiet */
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break;
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}
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if (aclcheck_result != ACLCHECK_OK)
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elog(ERROR, "%s: %s",
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relName, aclcheck_error_strings[aclcheck_result]);
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}
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}
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/* ===============================================================
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* ===============================================================
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static routines follow
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* ===============================================================
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* ===============================================================
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*/
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typedef struct execRowMark
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{
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Relation relation;
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Index rti;
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char resname[32];
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} execRowMark;
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typedef struct evalPlanQual
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{
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Plan *plan;
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Index rti;
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EState estate;
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struct evalPlanQual *free;
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} evalPlanQual;
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|
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/* ----------------------------------------------------------------
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* InitPlan
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*
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* Initializes the query plan: open files, allocate storage
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* and start up the rule manager
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* ----------------------------------------------------------------
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*/
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static TupleDesc
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InitPlan(CmdType operation, Query *parseTree, Plan *plan, EState *estate)
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{
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List *rangeTable;
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Relation intoRelationDesc;
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TupleDesc tupType;
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/*
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* Do permissions checks.
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*/
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ExecCheckQueryPerms(operation, parseTree, plan);
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/*
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* get information from query descriptor
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*/
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rangeTable = parseTree->rtable;
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/*
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* initialize the node's execution state
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*/
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estate->es_range_table = rangeTable;
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/*
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* if there is a result relation, initialize result relation stuff
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*/
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if (parseTree->resultRelation != 0 && operation != CMD_SELECT)
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{
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List *resultRelations = parseTree->resultRelations;
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int numResultRelations;
|
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ResultRelInfo *resultRelInfos;
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|
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if (resultRelations != NIL)
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{
|
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/*
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* Multiple result relations (due to inheritance)
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* parseTree->resultRelations identifies them all
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*/
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ResultRelInfo *resultRelInfo;
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numResultRelations = length(resultRelations);
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resultRelInfos = (ResultRelInfo *)
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palloc(numResultRelations * sizeof(ResultRelInfo));
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resultRelInfo = resultRelInfos;
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while (resultRelations != NIL)
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{
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initResultRelInfo(resultRelInfo,
|
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lfirsti(resultRelations),
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rangeTable,
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operation);
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resultRelInfo++;
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resultRelations = lnext(resultRelations);
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}
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}
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else
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{
|
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/*
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* Single result relation identified by
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* parseTree->resultRelation
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*/
|
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numResultRelations = 1;
|
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resultRelInfos = (ResultRelInfo *) palloc(sizeof(ResultRelInfo));
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initResultRelInfo(resultRelInfos,
|
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parseTree->resultRelation,
|
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rangeTable,
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operation);
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}
|
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|
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estate->es_result_relations = resultRelInfos;
|
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estate->es_num_result_relations = numResultRelations;
|
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/* Initialize to first or only result rel */
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estate->es_result_relation_info = resultRelInfos;
|
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}
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else
|
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{
|
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/*
|
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* if no result relation, then set state appropriately
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*/
|
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estate->es_result_relations = NULL;
|
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estate->es_num_result_relations = 0;
|
|
estate->es_result_relation_info = NULL;
|
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}
|
|
|
|
/*
|
|
* Have to lock relations selected for update
|
|
*/
|
|
estate->es_rowMark = NIL;
|
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if (parseTree->rowMarks != NIL)
|
|
{
|
|
List *l;
|
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|
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foreach(l, parseTree->rowMarks)
|
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{
|
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Index rti = lfirsti(l);
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Oid relid = getrelid(rti, rangeTable);
|
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Relation relation;
|
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execRowMark *erm;
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relation = heap_open(relid, RowShareLock);
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erm = (execRowMark *) palloc(sizeof(execRowMark));
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erm->relation = relation;
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erm->rti = rti;
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sprintf(erm->resname, "ctid%u", rti);
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estate->es_rowMark = lappend(estate->es_rowMark, erm);
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}
|
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}
|
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|
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/*
|
|
* initialize the executor "tuple" table. We need slots for all the
|
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* plan nodes, plus possibly output slots for the junkfilter(s). At
|
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* this point we aren't sure if we need junkfilters, so just add slots
|
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* for them unconditionally.
|
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*/
|
|
{
|
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int nSlots = ExecCountSlotsNode(plan);
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|
|
if (parseTree->resultRelations != NIL)
|
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nSlots += length(parseTree->resultRelations);
|
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else
|
|
nSlots += 1;
|
|
estate->es_tupleTable = ExecCreateTupleTable(nSlots);
|
|
}
|
|
|
|
/* mark EvalPlanQual not active */
|
|
estate->es_origPlan = plan;
|
|
estate->es_evalPlanQual = NULL;
|
|
estate->es_evTuple = NULL;
|
|
estate->es_evTupleNull = NULL;
|
|
estate->es_useEvalPlan = false;
|
|
|
|
/*
|
|
* initialize the private state information for all the nodes in the
|
|
* query tree. This opens files, allocates storage and leaves us
|
|
* ready to start processing tuples.
|
|
*/
|
|
ExecInitNode(plan, estate, NULL);
|
|
|
|
/*
|
|
* Get the tuple descriptor describing the type of tuples to return.
|
|
* (this is especially important if we are creating a relation with
|
|
* "retrieve into")
|
|
*/
|
|
tupType = ExecGetTupType(plan); /* tuple descriptor */
|
|
|
|
/*
|
|
* Initialize the junk filter if needed. SELECT and INSERT queries
|
|
* need a filter if there are any junk attrs in the tlist. UPDATE and
|
|
* DELETE always need one, since there's always a junk 'ctid'
|
|
* attribute present --- no need to look first.
|
|
*/
|
|
{
|
|
bool junk_filter_needed = false;
|
|
List *tlist;
|
|
|
|
switch (operation)
|
|
{
|
|
case CMD_SELECT:
|
|
case CMD_INSERT:
|
|
foreach(tlist, plan->targetlist)
|
|
{
|
|
TargetEntry *tle = (TargetEntry *) lfirst(tlist);
|
|
|
|
if (tle->resdom->resjunk)
|
|
{
|
|
junk_filter_needed = true;
|
|
break;
|
|
}
|
|
}
|
|
break;
|
|
case CMD_UPDATE:
|
|
case CMD_DELETE:
|
|
junk_filter_needed = true;
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
if (junk_filter_needed)
|
|
{
|
|
/*
|
|
* If there are multiple result relations, each one needs its
|
|
* own junk filter. Note this is only possible for
|
|
* UPDATE/DELETE, so we can't be fooled by some needing a
|
|
* filter and some not.
|
|
*/
|
|
if (parseTree->resultRelations != NIL)
|
|
{
|
|
List *subplans;
|
|
ResultRelInfo *resultRelInfo;
|
|
|
|
/* Top plan had better be an Append here. */
|
|
Assert(IsA(plan, Append));
|
|
Assert(((Append *) plan)->isTarget);
|
|
subplans = ((Append *) plan)->appendplans;
|
|
Assert(length(subplans) == estate->es_num_result_relations);
|
|
resultRelInfo = estate->es_result_relations;
|
|
while (subplans != NIL)
|
|
{
|
|
Plan *subplan = (Plan *) lfirst(subplans);
|
|
JunkFilter *j;
|
|
|
|
j = ExecInitJunkFilter(subplan->targetlist,
|
|
ExecGetTupType(subplan),
|
|
ExecAllocTableSlot(estate->es_tupleTable));
|
|
resultRelInfo->ri_junkFilter = j;
|
|
resultRelInfo++;
|
|
subplans = lnext(subplans);
|
|
}
|
|
|
|
/*
|
|
* Set active junkfilter too; at this point ExecInitAppend
|
|
* has already selected an active result relation...
|
|
*/
|
|
estate->es_junkFilter =
|
|
estate->es_result_relation_info->ri_junkFilter;
|
|
}
|
|
else
|
|
{
|
|
/* Normal case with just one JunkFilter */
|
|
JunkFilter *j;
|
|
|
|
j = ExecInitJunkFilter(plan->targetlist,
|
|
tupType,
|
|
ExecAllocTableSlot(estate->es_tupleTable));
|
|
estate->es_junkFilter = j;
|
|
if (estate->es_result_relation_info)
|
|
estate->es_result_relation_info->ri_junkFilter = j;
|
|
|
|
/* For SELECT, want to return the cleaned tuple type */
|
|
if (operation == CMD_SELECT)
|
|
tupType = j->jf_cleanTupType;
|
|
}
|
|
}
|
|
else
|
|
estate->es_junkFilter = NULL;
|
|
}
|
|
|
|
/*
|
|
* initialize the "into" relation
|
|
*/
|
|
intoRelationDesc = (Relation) NULL;
|
|
|
|
if (operation == CMD_SELECT)
|
|
{
|
|
char *intoName;
|
|
Oid intoRelationId;
|
|
TupleDesc tupdesc;
|
|
|
|
if (!parseTree->isPortal)
|
|
{
|
|
/*
|
|
* a select into table
|
|
*/
|
|
if (parseTree->into != NULL)
|
|
{
|
|
/*
|
|
* create the "into" relation
|
|
*/
|
|
intoName = parseTree->into;
|
|
|
|
/*
|
|
* have to copy tupType to get rid of constraints
|
|
*/
|
|
tupdesc = CreateTupleDescCopy(tupType);
|
|
|
|
intoRelationId =
|
|
heap_create_with_catalog(intoName,
|
|
tupdesc,
|
|
RELKIND_RELATION, true,
|
|
parseTree->isTemp,
|
|
allowSystemTableMods);
|
|
|
|
FreeTupleDesc(tupdesc);
|
|
|
|
/*
|
|
* Advance command counter so that the newly-created
|
|
* relation's catalog tuples will be visible to heap_open.
|
|
*/
|
|
CommandCounterIncrement();
|
|
|
|
/*
|
|
* If necessary, create a TOAST table for the into
|
|
* relation. Note that AlterTableCreateToastTable ends
|
|
* with CommandCounterIncrement(), so that the TOAST table
|
|
* will be visible for insertion.
|
|
*/
|
|
AlterTableCreateToastTable(intoName, true);
|
|
|
|
intoRelationDesc = heap_open(intoRelationId,
|
|
AccessExclusiveLock);
|
|
}
|
|
}
|
|
}
|
|
|
|
estate->es_into_relation_descriptor = intoRelationDesc;
|
|
|
|
return tupType;
|
|
}
|
|
|
|
/*
|
|
* Initialize ResultRelInfo data for one result relation
|
|
*/
|
|
static void
|
|
initResultRelInfo(ResultRelInfo *resultRelInfo,
|
|
Index resultRelationIndex,
|
|
List *rangeTable,
|
|
CmdType operation)
|
|
{
|
|
Oid resultRelationOid;
|
|
Relation resultRelationDesc;
|
|
|
|
resultRelationOid = getrelid(resultRelationIndex, rangeTable);
|
|
resultRelationDesc = heap_open(resultRelationOid, RowExclusiveLock);
|
|
|
|
switch (resultRelationDesc->rd_rel->relkind)
|
|
{
|
|
case RELKIND_SEQUENCE:
|
|
elog(ERROR, "You can't change sequence relation %s",
|
|
RelationGetRelationName(resultRelationDesc));
|
|
break;
|
|
case RELKIND_TOASTVALUE:
|
|
elog(ERROR, "You can't change toast relation %s",
|
|
RelationGetRelationName(resultRelationDesc));
|
|
break;
|
|
case RELKIND_VIEW:
|
|
elog(ERROR, "You can't change view relation %s",
|
|
RelationGetRelationName(resultRelationDesc));
|
|
break;
|
|
}
|
|
|
|
MemSet(resultRelInfo, 0, sizeof(ResultRelInfo));
|
|
resultRelInfo->type = T_ResultRelInfo;
|
|
resultRelInfo->ri_RangeTableIndex = resultRelationIndex;
|
|
resultRelInfo->ri_RelationDesc = resultRelationDesc;
|
|
resultRelInfo->ri_NumIndices = 0;
|
|
resultRelInfo->ri_IndexRelationDescs = NULL;
|
|
resultRelInfo->ri_IndexRelationInfo = NULL;
|
|
resultRelInfo->ri_TrigDesc = resultRelationDesc->trigdesc;
|
|
resultRelInfo->ri_TrigFunctions = NULL;
|
|
resultRelInfo->ri_ConstraintExprs = NULL;
|
|
resultRelInfo->ri_junkFilter = NULL;
|
|
|
|
/*
|
|
* If there are indices on the result relation, open them and save
|
|
* descriptors in the result relation info, so that we can add new
|
|
* index entries for the tuples we add/update. We need not do this
|
|
* for a DELETE, however, since deletion doesn't affect indexes.
|
|
*/
|
|
if (resultRelationDesc->rd_rel->relhasindex &&
|
|
operation != CMD_DELETE)
|
|
ExecOpenIndices(resultRelInfo);
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* EndPlan
|
|
*
|
|
* Cleans up the query plan -- closes files and free up storages
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
static void
|
|
EndPlan(Plan *plan, EState *estate)
|
|
{
|
|
ResultRelInfo *resultRelInfo;
|
|
int i;
|
|
List *l;
|
|
|
|
/*
|
|
* shut down any PlanQual processing we were doing
|
|
*/
|
|
if (estate->es_evalPlanQual != NULL)
|
|
EndEvalPlanQual(estate);
|
|
|
|
/*
|
|
* shut down the node-type-specific query processing
|
|
*/
|
|
ExecEndNode(plan, NULL);
|
|
|
|
/*
|
|
* destroy the executor "tuple" table.
|
|
*/
|
|
ExecDropTupleTable(estate->es_tupleTable, true);
|
|
estate->es_tupleTable = NULL;
|
|
|
|
/*
|
|
* close the result relation(s) if any, but hold locks until xact
|
|
* commit. Also clean up junkfilters if present.
|
|
*/
|
|
resultRelInfo = estate->es_result_relations;
|
|
for (i = estate->es_num_result_relations; i > 0; i--)
|
|
{
|
|
/* Close indices and then the relation itself */
|
|
ExecCloseIndices(resultRelInfo);
|
|
heap_close(resultRelInfo->ri_RelationDesc, NoLock);
|
|
/* Delete the junkfilter if any */
|
|
if (resultRelInfo->ri_junkFilter != NULL)
|
|
ExecFreeJunkFilter(resultRelInfo->ri_junkFilter);
|
|
resultRelInfo++;
|
|
}
|
|
|
|
/*
|
|
* close the "into" relation if necessary, again keeping lock
|
|
*/
|
|
if (estate->es_into_relation_descriptor != NULL)
|
|
heap_close(estate->es_into_relation_descriptor, NoLock);
|
|
|
|
/*
|
|
* There might be a junkfilter without a result relation.
|
|
*/
|
|
if (estate->es_num_result_relations == 0 &&
|
|
estate->es_junkFilter != NULL)
|
|
{
|
|
ExecFreeJunkFilter(estate->es_junkFilter);
|
|
estate->es_junkFilter = NULL;
|
|
}
|
|
|
|
/*
|
|
* close any relations selected FOR UPDATE, again keeping locks
|
|
*/
|
|
foreach(l, estate->es_rowMark)
|
|
{
|
|
execRowMark *erm = lfirst(l);
|
|
|
|
heap_close(erm->relation, NoLock);
|
|
}
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecutePlan
|
|
*
|
|
* processes the query plan to retrieve 'numberTuples' tuples in the
|
|
* direction specified.
|
|
* Retrieves all tuples if numberTuples is 0
|
|
*
|
|
* result is either a slot containing the last tuple in the case
|
|
* of a RETRIEVE or NULL otherwise.
|
|
*
|
|
* Note: the ctid attribute is a 'junk' attribute that is removed before the
|
|
* user can see it
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
static TupleTableSlot *
|
|
ExecutePlan(EState *estate,
|
|
Plan *plan,
|
|
CmdType operation,
|
|
long numberTuples,
|
|
ScanDirection direction,
|
|
DestReceiver *destfunc)
|
|
{
|
|
JunkFilter *junkfilter;
|
|
TupleTableSlot *slot;
|
|
ItemPointer tupleid = NULL;
|
|
ItemPointerData tuple_ctid;
|
|
long current_tuple_count;
|
|
TupleTableSlot *result;
|
|
|
|
/*
|
|
* initialize local variables
|
|
*/
|
|
slot = NULL;
|
|
current_tuple_count = 0;
|
|
result = NULL;
|
|
|
|
/*
|
|
* Set the direction.
|
|
*/
|
|
estate->es_direction = direction;
|
|
|
|
/*
|
|
* Loop until we've processed the proper number of tuples from the
|
|
* plan.
|
|
*/
|
|
|
|
for (;;)
|
|
{
|
|
/* Reset the per-output-tuple exprcontext */
|
|
ResetPerTupleExprContext(estate);
|
|
|
|
/*
|
|
* Execute the plan and obtain a tuple
|
|
*/
|
|
lnext: ;
|
|
if (estate->es_useEvalPlan)
|
|
{
|
|
slot = EvalPlanQualNext(estate);
|
|
if (TupIsNull(slot))
|
|
slot = ExecProcNode(plan, NULL);
|
|
}
|
|
else
|
|
slot = ExecProcNode(plan, NULL);
|
|
|
|
/*
|
|
* if the tuple is null, then we assume there is nothing more to
|
|
* process so we just return null...
|
|
*/
|
|
if (TupIsNull(slot))
|
|
{
|
|
result = NULL;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* if we have a junk filter, then project a new tuple with the
|
|
* junk removed.
|
|
*
|
|
* Store this new "clean" tuple in the junkfilter's resultSlot.
|
|
* (Formerly, we stored it back over the "dirty" tuple, which is
|
|
* WRONG because that tuple slot has the wrong descriptor.)
|
|
*
|
|
* Also, extract all the junk information we need.
|
|
*/
|
|
if ((junkfilter = estate->es_junkFilter) != (JunkFilter *) NULL)
|
|
{
|
|
Datum datum;
|
|
HeapTuple newTuple;
|
|
bool isNull;
|
|
|
|
/*
|
|
* extract the 'ctid' junk attribute.
|
|
*/
|
|
if (operation == CMD_UPDATE || operation == CMD_DELETE)
|
|
{
|
|
if (!ExecGetJunkAttribute(junkfilter,
|
|
slot,
|
|
"ctid",
|
|
&datum,
|
|
&isNull))
|
|
elog(ERROR, "ExecutePlan: NO (junk) `ctid' was found!");
|
|
|
|
/* shouldn't ever get a null result... */
|
|
if (isNull)
|
|
elog(ERROR, "ExecutePlan: (junk) `ctid' is NULL!");
|
|
|
|
tupleid = (ItemPointer) DatumGetPointer(datum);
|
|
tuple_ctid = *tupleid; /* make sure we don't free the
|
|
* ctid!! */
|
|
tupleid = &tuple_ctid;
|
|
}
|
|
else if (estate->es_rowMark != NIL)
|
|
{
|
|
List *l;
|
|
|
|
lmark: ;
|
|
foreach(l, estate->es_rowMark)
|
|
{
|
|
execRowMark *erm = lfirst(l);
|
|
Buffer buffer;
|
|
HeapTupleData tuple;
|
|
TupleTableSlot *newSlot;
|
|
int test;
|
|
|
|
if (!ExecGetJunkAttribute(junkfilter,
|
|
slot,
|
|
erm->resname,
|
|
&datum,
|
|
&isNull))
|
|
elog(ERROR, "ExecutePlan: NO (junk) `%s' was found!",
|
|
erm->resname);
|
|
|
|
/* shouldn't ever get a null result... */
|
|
if (isNull)
|
|
elog(ERROR, "ExecutePlan: (junk) `%s' is NULL!",
|
|
erm->resname);
|
|
|
|
tuple.t_self = *((ItemPointer) DatumGetPointer(datum));
|
|
test = heap_mark4update(erm->relation, &tuple, &buffer);
|
|
ReleaseBuffer(buffer);
|
|
switch (test)
|
|
{
|
|
case HeapTupleSelfUpdated:
|
|
case HeapTupleMayBeUpdated:
|
|
break;
|
|
|
|
case HeapTupleUpdated:
|
|
if (XactIsoLevel == XACT_SERIALIZABLE)
|
|
elog(ERROR, "Can't serialize access due to concurrent update");
|
|
if (!(ItemPointerEquals(&(tuple.t_self),
|
|
(ItemPointer) DatumGetPointer(datum))))
|
|
{
|
|
newSlot = EvalPlanQual(estate, erm->rti, &(tuple.t_self));
|
|
if (!(TupIsNull(newSlot)))
|
|
{
|
|
slot = newSlot;
|
|
estate->es_useEvalPlan = true;
|
|
goto lmark;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* if tuple was deleted or PlanQual failed for
|
|
* updated tuple - we must not return this
|
|
* tuple!
|
|
*/
|
|
goto lnext;
|
|
|
|
default:
|
|
elog(ERROR, "Unknown status %u from heap_mark4update", test);
|
|
return (NULL);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Finally create a new "clean" tuple with all junk attributes
|
|
* removed
|
|
*/
|
|
newTuple = ExecRemoveJunk(junkfilter, slot);
|
|
|
|
slot = ExecStoreTuple(newTuple, /* tuple to store */
|
|
junkfilter->jf_resultSlot, /* dest slot */
|
|
InvalidBuffer, /* this tuple has no
|
|
* buffer */
|
|
true); /* tuple should be pfreed */
|
|
} /* if (junkfilter... */
|
|
|
|
/*
|
|
* now that we have a tuple, do the appropriate thing with it..
|
|
* either return it to the user, add it to a relation someplace,
|
|
* delete it from a relation, or modify some of its attributes.
|
|
*/
|
|
|
|
switch (operation)
|
|
{
|
|
case CMD_SELECT:
|
|
ExecRetrieve(slot, /* slot containing tuple */
|
|
destfunc, /* destination's tuple-receiver
|
|
* obj */
|
|
estate); /* */
|
|
result = slot;
|
|
break;
|
|
|
|
case CMD_INSERT:
|
|
ExecAppend(slot, tupleid, estate);
|
|
result = NULL;
|
|
break;
|
|
|
|
case CMD_DELETE:
|
|
ExecDelete(slot, tupleid, estate);
|
|
result = NULL;
|
|
break;
|
|
|
|
case CMD_UPDATE:
|
|
ExecReplace(slot, tupleid, estate);
|
|
result = NULL;
|
|
break;
|
|
|
|
default:
|
|
elog(LOG, "ExecutePlan: unknown operation in queryDesc");
|
|
result = NULL;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* check our tuple count.. if we've processed the proper number
|
|
* then quit, else loop again and process more tuples..
|
|
*/
|
|
current_tuple_count++;
|
|
if (numberTuples == current_tuple_count)
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* here, result is either a slot containing a tuple in the case of a
|
|
* RETRIEVE or NULL otherwise.
|
|
*/
|
|
return result;
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecRetrieve
|
|
*
|
|
* RETRIEVEs are easy.. we just pass the tuple to the appropriate
|
|
* print function. The only complexity is when we do a
|
|
* "retrieve into", in which case we insert the tuple into
|
|
* the appropriate relation (note: this is a newly created relation
|
|
* so we don't need to worry about indices or locks.)
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
static void
|
|
ExecRetrieve(TupleTableSlot *slot,
|
|
DestReceiver *destfunc,
|
|
EState *estate)
|
|
{
|
|
HeapTuple tuple;
|
|
TupleDesc attrtype;
|
|
|
|
/*
|
|
* get the heap tuple out of the tuple table slot
|
|
*/
|
|
tuple = slot->val;
|
|
attrtype = slot->ttc_tupleDescriptor;
|
|
|
|
/*
|
|
* insert the tuple into the "into relation"
|
|
*/
|
|
if (estate->es_into_relation_descriptor != NULL)
|
|
{
|
|
heap_insert(estate->es_into_relation_descriptor, tuple);
|
|
IncrAppended();
|
|
}
|
|
|
|
/*
|
|
* send the tuple to the front end (or the screen)
|
|
*/
|
|
(*destfunc->receiveTuple) (tuple, attrtype, destfunc);
|
|
IncrRetrieved();
|
|
(estate->es_processed)++;
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecAppend
|
|
*
|
|
* APPENDs are trickier.. we have to insert the tuple into
|
|
* the base relation and insert appropriate tuples into the
|
|
* index relations.
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
|
|
static void
|
|
ExecAppend(TupleTableSlot *slot,
|
|
ItemPointer tupleid,
|
|
EState *estate)
|
|
{
|
|
HeapTuple tuple;
|
|
ResultRelInfo *resultRelInfo;
|
|
Relation resultRelationDesc;
|
|
int numIndices;
|
|
Oid newId;
|
|
|
|
/*
|
|
* get the heap tuple out of the tuple table slot
|
|
*/
|
|
tuple = slot->val;
|
|
|
|
/*
|
|
* get information on the (current) result relation
|
|
*/
|
|
resultRelInfo = estate->es_result_relation_info;
|
|
resultRelationDesc = resultRelInfo->ri_RelationDesc;
|
|
|
|
/* BEFORE ROW INSERT Triggers */
|
|
if (resultRelInfo->ri_TrigDesc &&
|
|
resultRelInfo->ri_TrigDesc->n_before_row[TRIGGER_EVENT_INSERT] > 0)
|
|
{
|
|
HeapTuple newtuple;
|
|
|
|
newtuple = ExecBRInsertTriggers(estate, resultRelInfo, tuple);
|
|
|
|
if (newtuple == NULL) /* "do nothing" */
|
|
return;
|
|
|
|
if (newtuple != tuple) /* modified by Trigger(s) */
|
|
{
|
|
/*
|
|
* Insert modified tuple into tuple table slot, replacing the
|
|
* original. We assume that it was allocated in per-tuple
|
|
* memory context, and therefore will go away by itself. The
|
|
* tuple table slot should not try to clear it.
|
|
*/
|
|
ExecStoreTuple(newtuple, slot, InvalidBuffer, false);
|
|
tuple = newtuple;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Check the constraints of the tuple
|
|
*/
|
|
if (resultRelationDesc->rd_att->constr)
|
|
ExecConstraints("ExecAppend", resultRelInfo, slot, estate);
|
|
|
|
/*
|
|
* insert the tuple
|
|
*/
|
|
newId = heap_insert(resultRelationDesc, tuple);
|
|
|
|
IncrAppended();
|
|
(estate->es_processed)++;
|
|
estate->es_lastoid = newId;
|
|
setLastTid(&(tuple->t_self));
|
|
|
|
/*
|
|
* process indices
|
|
*
|
|
* Note: heap_insert adds a new tuple to a relation. As a side effect,
|
|
* the tupleid of the new tuple is placed in the new tuple's t_ctid
|
|
* field.
|
|
*/
|
|
numIndices = resultRelInfo->ri_NumIndices;
|
|
if (numIndices > 0)
|
|
ExecInsertIndexTuples(slot, &(tuple->t_self), estate, false);
|
|
|
|
/* AFTER ROW INSERT Triggers */
|
|
if (resultRelInfo->ri_TrigDesc)
|
|
ExecARInsertTriggers(estate, resultRelInfo, tuple);
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecDelete
|
|
*
|
|
* DELETE is like append, we delete the tuple and its
|
|
* index tuples.
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
static void
|
|
ExecDelete(TupleTableSlot *slot,
|
|
ItemPointer tupleid,
|
|
EState *estate)
|
|
{
|
|
ResultRelInfo *resultRelInfo;
|
|
Relation resultRelationDesc;
|
|
ItemPointerData ctid;
|
|
int result;
|
|
|
|
/*
|
|
* get information on the (current) result relation
|
|
*/
|
|
resultRelInfo = estate->es_result_relation_info;
|
|
resultRelationDesc = resultRelInfo->ri_RelationDesc;
|
|
|
|
/* BEFORE ROW DELETE Triggers */
|
|
if (resultRelInfo->ri_TrigDesc &&
|
|
resultRelInfo->ri_TrigDesc->n_before_row[TRIGGER_EVENT_DELETE] > 0)
|
|
{
|
|
bool dodelete;
|
|
|
|
dodelete = ExecBRDeleteTriggers(estate, resultRelInfo, tupleid);
|
|
|
|
if (!dodelete) /* "do nothing" */
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* delete the tuple
|
|
*/
|
|
ldelete:;
|
|
result = heap_delete(resultRelationDesc, tupleid, &ctid);
|
|
switch (result)
|
|
{
|
|
case HeapTupleSelfUpdated:
|
|
return;
|
|
|
|
case HeapTupleMayBeUpdated:
|
|
break;
|
|
|
|
case HeapTupleUpdated:
|
|
if (XactIsoLevel == XACT_SERIALIZABLE)
|
|
elog(ERROR, "Can't serialize access due to concurrent update");
|
|
else if (!(ItemPointerEquals(tupleid, &ctid)))
|
|
{
|
|
TupleTableSlot *epqslot = EvalPlanQual(estate,
|
|
resultRelInfo->ri_RangeTableIndex, &ctid);
|
|
|
|
if (!TupIsNull(epqslot))
|
|
{
|
|
*tupleid = ctid;
|
|
goto ldelete;
|
|
}
|
|
}
|
|
/* tuple already deleted; nothing to do */
|
|
return;
|
|
|
|
default:
|
|
elog(ERROR, "Unknown status %u from heap_delete", result);
|
|
return;
|
|
}
|
|
|
|
IncrDeleted();
|
|
(estate->es_processed)++;
|
|
|
|
/*
|
|
* Note: Normally one would think that we have to delete index tuples
|
|
* associated with the heap tuple now..
|
|
*
|
|
* ... but in POSTGRES, we have no need to do this because the vacuum
|
|
* daemon automatically opens an index scan and deletes index tuples
|
|
* when it finds deleted heap tuples. -cim 9/27/89
|
|
*/
|
|
|
|
/* AFTER ROW DELETE Triggers */
|
|
if (resultRelInfo->ri_TrigDesc)
|
|
ExecARDeleteTriggers(estate, resultRelInfo, tupleid);
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecReplace
|
|
*
|
|
* note: we can't run replace queries with transactions
|
|
* off because replaces are actually appends and our
|
|
* scan will mistakenly loop forever, replacing the tuple
|
|
* it just appended.. This should be fixed but until it
|
|
* is, we don't want to get stuck in an infinite loop
|
|
* which corrupts your database..
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
static void
|
|
ExecReplace(TupleTableSlot *slot,
|
|
ItemPointer tupleid,
|
|
EState *estate)
|
|
{
|
|
HeapTuple tuple;
|
|
ResultRelInfo *resultRelInfo;
|
|
Relation resultRelationDesc;
|
|
ItemPointerData ctid;
|
|
int result;
|
|
int numIndices;
|
|
|
|
/*
|
|
* abort the operation if not running transactions
|
|
*/
|
|
if (IsBootstrapProcessingMode())
|
|
{
|
|
elog(WARNING, "ExecReplace: replace can't run without transactions");
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* get the heap tuple out of the tuple table slot
|
|
*/
|
|
tuple = slot->val;
|
|
|
|
/*
|
|
* get information on the (current) result relation
|
|
*/
|
|
resultRelInfo = estate->es_result_relation_info;
|
|
resultRelationDesc = resultRelInfo->ri_RelationDesc;
|
|
|
|
/* 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);
|
|
|
|
if (newtuple == NULL) /* "do nothing" */
|
|
return;
|
|
|
|
if (newtuple != tuple) /* modified by Trigger(s) */
|
|
{
|
|
/*
|
|
* Insert modified tuple into tuple table slot, replacing the
|
|
* original. We assume that it was allocated in per-tuple
|
|
* memory context, and therefore will go away by itself. The
|
|
* tuple table slot should not try to clear it.
|
|
*/
|
|
ExecStoreTuple(newtuple, slot, InvalidBuffer, false);
|
|
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 mark4update to lock the correct tuple, so
|
|
* there's no need to do them again.)
|
|
*/
|
|
lreplace:;
|
|
if (resultRelationDesc->rd_att->constr)
|
|
ExecConstraints("ExecReplace", resultRelInfo, slot, estate);
|
|
|
|
/*
|
|
* replace the heap tuple
|
|
*/
|
|
result = heap_update(resultRelationDesc, tupleid, tuple, &ctid);
|
|
switch (result)
|
|
{
|
|
case HeapTupleSelfUpdated:
|
|
return;
|
|
|
|
case HeapTupleMayBeUpdated:
|
|
break;
|
|
|
|
case HeapTupleUpdated:
|
|
if (XactIsoLevel == XACT_SERIALIZABLE)
|
|
elog(ERROR, "Can't serialize access due to concurrent update");
|
|
else if (!(ItemPointerEquals(tupleid, &ctid)))
|
|
{
|
|
TupleTableSlot *epqslot = EvalPlanQual(estate,
|
|
resultRelInfo->ri_RangeTableIndex, &ctid);
|
|
|
|
if (!TupIsNull(epqslot))
|
|
{
|
|
*tupleid = ctid;
|
|
tuple = ExecRemoveJunk(estate->es_junkFilter, epqslot);
|
|
slot = ExecStoreTuple(tuple,
|
|
estate->es_junkFilter->jf_resultSlot,
|
|
InvalidBuffer, true);
|
|
goto lreplace;
|
|
}
|
|
}
|
|
/* tuple already deleted; nothing to do */
|
|
return;
|
|
|
|
default:
|
|
elog(ERROR, "Unknown status %u from heap_update", result);
|
|
return;
|
|
}
|
|
|
|
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 replaces are actually deletes and inserts and index
|
|
* tuple deletion is done automagically by the vacuum daemon. All we
|
|
* do is insert new index tuples. -cim 9/27/89
|
|
*/
|
|
|
|
/*
|
|
* process indices
|
|
*
|
|
* heap_update updates a tuple in the base relation by invalidating it
|
|
* and then appending a new tuple to the relation. As a side effect,
|
|
* the tupleid of the new tuple is placed in the new tuple's t_ctid
|
|
* field. So we now insert index tuples using the new tupleid stored
|
|
* there.
|
|
*/
|
|
|
|
numIndices = resultRelInfo->ri_NumIndices;
|
|
if (numIndices > 0)
|
|
ExecInsertIndexTuples(slot, &(tuple->t_self), estate, true);
|
|
|
|
/* AFTER ROW UPDATE Triggers */
|
|
if (resultRelInfo->ri_TrigDesc)
|
|
ExecARUpdateTriggers(estate, resultRelInfo, tupleid, tuple);
|
|
}
|
|
|
|
static char *
|
|
ExecRelCheck(ResultRelInfo *resultRelInfo,
|
|
TupleTableSlot *slot, EState *estate)
|
|
{
|
|
Relation rel = resultRelInfo->ri_RelationDesc;
|
|
int ncheck = rel->rd_att->constr->num_check;
|
|
ConstrCheck *check = rel->rd_att->constr->check;
|
|
ExprContext *econtext;
|
|
MemoryContext oldContext;
|
|
List *qual;
|
|
int i;
|
|
|
|
/*
|
|
* If first time through for this result relation, build expression
|
|
* nodetrees for rel's constraint expressions. Keep them in the
|
|
* per-query memory context so they'll survive throughout the query.
|
|
*/
|
|
if (resultRelInfo->ri_ConstraintExprs == NULL)
|
|
{
|
|
oldContext = MemoryContextSwitchTo(estate->es_query_cxt);
|
|
resultRelInfo->ri_ConstraintExprs =
|
|
(List **) palloc(ncheck * sizeof(List *));
|
|
for (i = 0; i < ncheck; i++)
|
|
{
|
|
qual = (List *) stringToNode(check[i].ccbin);
|
|
resultRelInfo->ri_ConstraintExprs[i] = qual;
|
|
}
|
|
MemoryContextSwitchTo(oldContext);
|
|
}
|
|
|
|
/*
|
|
* We will use the EState's per-tuple context for evaluating
|
|
* constraint expressions (creating it if it's not already there).
|
|
*/
|
|
econtext = GetPerTupleExprContext(estate);
|
|
|
|
/* Arrange for econtext's scan tuple to be the tuple under test */
|
|
econtext->ecxt_scantuple = slot;
|
|
|
|
/* And evaluate the constraints */
|
|
for (i = 0; i < ncheck; i++)
|
|
{
|
|
qual = resultRelInfo->ri_ConstraintExprs[i];
|
|
|
|
/*
|
|
* NOTE: SQL92 specifies that a NULL result from a constraint
|
|
* expression is not to be treated as a failure. Therefore, tell
|
|
* ExecQual to return TRUE for NULL.
|
|
*/
|
|
if (!ExecQual(qual, econtext, true))
|
|
return check[i].ccname;
|
|
}
|
|
|
|
/* NULL result means no error */
|
|
return (char *) NULL;
|
|
}
|
|
|
|
void
|
|
ExecConstraints(char *caller, ResultRelInfo *resultRelInfo,
|
|
TupleTableSlot *slot, EState *estate)
|
|
{
|
|
Relation rel = resultRelInfo->ri_RelationDesc;
|
|
HeapTuple tuple = slot->val;
|
|
TupleConstr *constr = rel->rd_att->constr;
|
|
|
|
Assert(constr);
|
|
|
|
if (constr->has_not_null)
|
|
{
|
|
int natts = rel->rd_att->natts;
|
|
int attrChk;
|
|
|
|
for (attrChk = 1; attrChk <= natts; attrChk++)
|
|
{
|
|
if (rel->rd_att->attrs[attrChk - 1]->attnotnull &&
|
|
heap_attisnull(tuple, attrChk))
|
|
elog(ERROR, "%s: Fail to add null value in not null attribute %s",
|
|
caller, NameStr(rel->rd_att->attrs[attrChk - 1]->attname));
|
|
}
|
|
}
|
|
|
|
if (constr->num_check > 0)
|
|
{
|
|
char *failed;
|
|
|
|
if ((failed = ExecRelCheck(resultRelInfo, slot, estate)) != NULL)
|
|
elog(ERROR, "%s: rejected due to CHECK constraint %s",
|
|
caller, failed);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Check a modified tuple to see if we want to process its updated version
|
|
* under READ COMMITTED rules.
|
|
*
|
|
* See backend/executor/README for some info about how this works.
|
|
*/
|
|
TupleTableSlot *
|
|
EvalPlanQual(EState *estate, Index rti, ItemPointer tid)
|
|
{
|
|
evalPlanQual *epq;
|
|
EState *epqstate;
|
|
Relation relation;
|
|
HeapTupleData tuple;
|
|
HeapTuple copyTuple = NULL;
|
|
int rtsize;
|
|
bool endNode;
|
|
|
|
Assert(rti != 0);
|
|
|
|
/*
|
|
* find relation containing target tuple
|
|
*/
|
|
if (estate->es_result_relation_info != NULL &&
|
|
estate->es_result_relation_info->ri_RangeTableIndex == rti)
|
|
relation = estate->es_result_relation_info->ri_RelationDesc;
|
|
else
|
|
{
|
|
List *l;
|
|
|
|
relation = NULL;
|
|
foreach(l, estate->es_rowMark)
|
|
{
|
|
if (((execRowMark *) lfirst(l))->rti == rti)
|
|
{
|
|
relation = ((execRowMark *) lfirst(l))->relation;
|
|
break;
|
|
}
|
|
}
|
|
if (relation == NULL)
|
|
elog(ERROR, "EvalPlanQual: can't find RTE %d", (int) rti);
|
|
}
|
|
|
|
/*
|
|
* fetch tid tuple
|
|
*
|
|
* Loop here to deal with updated or busy tuples
|
|
*/
|
|
tuple.t_self = *tid;
|
|
for (;;)
|
|
{
|
|
Buffer buffer;
|
|
|
|
heap_fetch(relation, SnapshotDirty, &tuple, &buffer, NULL);
|
|
if (tuple.t_data != NULL)
|
|
{
|
|
TransactionId xwait = SnapshotDirty->xmax;
|
|
|
|
if (TransactionIdIsValid(SnapshotDirty->xmin))
|
|
elog(ERROR, "EvalPlanQual: t_xmin is uncommitted ?!");
|
|
|
|
/*
|
|
* If tuple is being updated by other transaction then we have
|
|
* to wait for its commit/abort.
|
|
*/
|
|
if (TransactionIdIsValid(xwait))
|
|
{
|
|
ReleaseBuffer(buffer);
|
|
XactLockTableWait(xwait);
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* We got tuple - now copy it for use by recheck query.
|
|
*/
|
|
copyTuple = heap_copytuple(&tuple);
|
|
ReleaseBuffer(buffer);
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Oops! Invalid tuple. Have to check is it updated or deleted.
|
|
* Note that it's possible to get invalid SnapshotDirty->tid if
|
|
* tuple updated by this transaction. Have we to check this ?
|
|
*/
|
|
if (ItemPointerIsValid(&(SnapshotDirty->tid)) &&
|
|
!(ItemPointerEquals(&(tuple.t_self), &(SnapshotDirty->tid))))
|
|
{
|
|
/* updated, so look at the updated copy */
|
|
tuple.t_self = SnapshotDirty->tid;
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Deleted or updated by this transaction; forget it.
|
|
*/
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* For UPDATE/DELETE we have to return tid of actual row we're
|
|
* executing PQ for.
|
|
*/
|
|
*tid = tuple.t_self;
|
|
|
|
/*
|
|
* Need to run a recheck subquery. Find or create a PQ stack entry.
|
|
*/
|
|
epq = (evalPlanQual *) estate->es_evalPlanQual;
|
|
rtsize = length(estate->es_range_table);
|
|
endNode = true;
|
|
|
|
if (epq != NULL && epq->rti == 0)
|
|
{
|
|
/* Top PQ stack entry is idle, so re-use it */
|
|
Assert(!(estate->es_useEvalPlan) &&
|
|
epq->estate.es_evalPlanQual == NULL);
|
|
epq->rti = rti;
|
|
endNode = false;
|
|
}
|
|
|
|
/*
|
|
* If this is request for another RTE - Ra, - then we have to check
|
|
* wasn't PlanQual requested for Ra already and if so then Ra' row was
|
|
* updated again and we have to re-start old execution for Ra and
|
|
* forget all what we done after Ra was suspended. Cool? -:))
|
|
*/
|
|
if (epq != NULL && epq->rti != rti &&
|
|
epq->estate.es_evTuple[rti - 1] != NULL)
|
|
{
|
|
do
|
|
{
|
|
evalPlanQual *oldepq;
|
|
|
|
/* pop previous PlanQual from the stack */
|
|
epqstate = &(epq->estate);
|
|
oldepq = (evalPlanQual *) epqstate->es_evalPlanQual;
|
|
Assert(oldepq->rti != 0);
|
|
/* stop execution */
|
|
ExecEndNode(epq->plan, NULL);
|
|
ExecDropTupleTable(epqstate->es_tupleTable, true);
|
|
epqstate->es_tupleTable = NULL;
|
|
heap_freetuple(epqstate->es_evTuple[epq->rti - 1]);
|
|
epqstate->es_evTuple[epq->rti - 1] = NULL;
|
|
/* push current PQ to freePQ stack */
|
|
oldepq->free = epq;
|
|
epq = oldepq;
|
|
estate->es_evalPlanQual = (Pointer) epq;
|
|
} while (epq->rti != rti);
|
|
}
|
|
|
|
/*
|
|
* If we are requested for another RTE then we have to suspend
|
|
* execution of current PlanQual and start execution for new one.
|
|
*/
|
|
if (epq == NULL || epq->rti != rti)
|
|
{
|
|
/* try to reuse plan used previously */
|
|
evalPlanQual *newepq = (epq != NULL) ? epq->free : NULL;
|
|
|
|
if (newepq == NULL) /* first call or freePQ stack is empty */
|
|
{
|
|
newepq = (evalPlanQual *) palloc(sizeof(evalPlanQual));
|
|
newepq->free = NULL;
|
|
|
|
/*
|
|
* Each stack level has its own copy of the plan tree. This
|
|
* is wasteful, but necessary as long as plan nodes point to
|
|
* exec state nodes rather than vice versa. Note that
|
|
* copyfuncs.c doesn't attempt to copy the exec state nodes,
|
|
* which is a good thing in this situation.
|
|
*/
|
|
newepq->plan = copyObject(estate->es_origPlan);
|
|
|
|
/*
|
|
* Init stack level's EState. We share top level's copy of
|
|
* es_result_relations array and other non-changing status. We
|
|
* need our own tupletable, es_param_exec_vals, and other
|
|
* changeable state.
|
|
*/
|
|
epqstate = &(newepq->estate);
|
|
memcpy(epqstate, estate, sizeof(EState));
|
|
epqstate->es_direction = ForwardScanDirection;
|
|
if (estate->es_origPlan->nParamExec > 0)
|
|
epqstate->es_param_exec_vals = (ParamExecData *)
|
|
palloc(estate->es_origPlan->nParamExec *
|
|
sizeof(ParamExecData));
|
|
epqstate->es_tupleTable = NULL;
|
|
epqstate->es_per_tuple_exprcontext = NULL;
|
|
|
|
/*
|
|
* Each epqstate must have its own es_evTupleNull state, but
|
|
* all the stack entries share es_evTuple state. This allows
|
|
* sub-rechecks to inherit the value being examined by an
|
|
* outer recheck.
|
|
*/
|
|
epqstate->es_evTupleNull = (bool *) palloc(rtsize * sizeof(bool));
|
|
if (epq == NULL)
|
|
{
|
|
/* first PQ stack entry */
|
|
epqstate->es_evTuple = (HeapTuple *)
|
|
palloc(rtsize * sizeof(HeapTuple));
|
|
memset(epqstate->es_evTuple, 0, rtsize * sizeof(HeapTuple));
|
|
}
|
|
else
|
|
{
|
|
/* later stack entries share the same storage */
|
|
epqstate->es_evTuple = epq->estate.es_evTuple;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* recycle previously used EState */
|
|
epqstate = &(newepq->estate);
|
|
}
|
|
/* push current PQ to the stack */
|
|
epqstate->es_evalPlanQual = (Pointer) epq;
|
|
epq = newepq;
|
|
estate->es_evalPlanQual = (Pointer) epq;
|
|
epq->rti = rti;
|
|
endNode = false;
|
|
}
|
|
|
|
Assert(epq->rti == rti);
|
|
epqstate = &(epq->estate);
|
|
|
|
/*
|
|
* Ok - we're requested for the same RTE. Unfortunately we still have
|
|
* to end and restart execution of the plan, because ExecReScan
|
|
* wouldn't ensure that upper plan nodes would reset themselves. We
|
|
* could make that work if insertion of the target tuple were
|
|
* integrated with the Param mechanism somehow, so that the upper plan
|
|
* nodes know that their children's outputs have changed.
|
|
*/
|
|
if (endNode)
|
|
{
|
|
/* stop execution */
|
|
ExecEndNode(epq->plan, NULL);
|
|
ExecDropTupleTable(epqstate->es_tupleTable, true);
|
|
epqstate->es_tupleTable = NULL;
|
|
}
|
|
|
|
/*
|
|
* free old RTE' tuple, if any, and store target tuple where
|
|
* relation's scan node will see it
|
|
*/
|
|
if (epqstate->es_evTuple[rti - 1] != NULL)
|
|
heap_freetuple(epqstate->es_evTuple[rti - 1]);
|
|
epqstate->es_evTuple[rti - 1] = copyTuple;
|
|
|
|
/*
|
|
* Initialize for new recheck query; be careful to copy down state
|
|
* that might have changed in top EState.
|
|
*/
|
|
epqstate->es_result_relation_info = estate->es_result_relation_info;
|
|
epqstate->es_junkFilter = estate->es_junkFilter;
|
|
if (estate->es_origPlan->nParamExec > 0)
|
|
memset(epqstate->es_param_exec_vals, 0,
|
|
estate->es_origPlan->nParamExec * sizeof(ParamExecData));
|
|
memset(epqstate->es_evTupleNull, false, rtsize * sizeof(bool));
|
|
epqstate->es_useEvalPlan = false;
|
|
Assert(epqstate->es_tupleTable == NULL);
|
|
epqstate->es_tupleTable =
|
|
ExecCreateTupleTable(estate->es_tupleTable->size);
|
|
|
|
ExecInitNode(epq->plan, epqstate, NULL);
|
|
|
|
return EvalPlanQualNext(estate);
|
|
}
|
|
|
|
static TupleTableSlot *
|
|
EvalPlanQualNext(EState *estate)
|
|
{
|
|
evalPlanQual *epq = (evalPlanQual *) estate->es_evalPlanQual;
|
|
EState *epqstate = &(epq->estate);
|
|
evalPlanQual *oldepq;
|
|
TupleTableSlot *slot;
|
|
|
|
Assert(epq->rti != 0);
|
|
|
|
lpqnext:;
|
|
slot = ExecProcNode(epq->plan, NULL);
|
|
|
|
/*
|
|
* No more tuples for this PQ. Continue previous one.
|
|
*/
|
|
if (TupIsNull(slot))
|
|
{
|
|
/* stop execution */
|
|
ExecEndNode(epq->plan, NULL);
|
|
ExecDropTupleTable(epqstate->es_tupleTable, true);
|
|
epqstate->es_tupleTable = NULL;
|
|
heap_freetuple(epqstate->es_evTuple[epq->rti - 1]);
|
|
epqstate->es_evTuple[epq->rti - 1] = NULL;
|
|
/* pop old PQ from the stack */
|
|
oldepq = (evalPlanQual *) epqstate->es_evalPlanQual;
|
|
if (oldepq == (evalPlanQual *) NULL)
|
|
{
|
|
epq->rti = 0; /* this is the first (oldest) */
|
|
estate->es_useEvalPlan = false; /* PQ - mark as free and */
|
|
return (NULL); /* continue Query execution */
|
|
}
|
|
Assert(oldepq->rti != 0);
|
|
/* push current PQ to freePQ stack */
|
|
oldepq->free = epq;
|
|
epq = oldepq;
|
|
epqstate = &(epq->estate);
|
|
estate->es_evalPlanQual = (Pointer) epq;
|
|
goto lpqnext;
|
|
}
|
|
|
|
return (slot);
|
|
}
|
|
|
|
static void
|
|
EndEvalPlanQual(EState *estate)
|
|
{
|
|
evalPlanQual *epq = (evalPlanQual *) estate->es_evalPlanQual;
|
|
EState *epqstate = &(epq->estate);
|
|
evalPlanQual *oldepq;
|
|
|
|
if (epq->rti == 0) /* plans already shutdowned */
|
|
{
|
|
Assert(epq->estate.es_evalPlanQual == NULL);
|
|
return;
|
|
}
|
|
|
|
for (;;)
|
|
{
|
|
/* stop execution */
|
|
ExecEndNode(epq->plan, NULL);
|
|
ExecDropTupleTable(epqstate->es_tupleTable, true);
|
|
epqstate->es_tupleTable = NULL;
|
|
if (epqstate->es_evTuple[epq->rti - 1] != NULL)
|
|
{
|
|
heap_freetuple(epqstate->es_evTuple[epq->rti - 1]);
|
|
epqstate->es_evTuple[epq->rti - 1] = NULL;
|
|
}
|
|
/* pop old PQ from the stack */
|
|
oldepq = (evalPlanQual *) epqstate->es_evalPlanQual;
|
|
if (oldepq == (evalPlanQual *) NULL)
|
|
{
|
|
epq->rti = 0; /* this is the first (oldest) */
|
|
estate->es_useEvalPlan = false; /* PQ - mark as free */
|
|
break;
|
|
}
|
|
Assert(oldepq->rti != 0);
|
|
/* push current PQ to freePQ stack */
|
|
oldepq->free = epq;
|
|
epq = oldepq;
|
|
epqstate = &(epq->estate);
|
|
estate->es_evalPlanQual = (Pointer) epq;
|
|
}
|
|
}
|