mirror of
https://git.postgresql.org/git/postgresql.git
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2060 lines
51 KiB
C
2060 lines
51 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* The old ExecutorMain() has been replaced by ExecutorStart(),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 'feature' 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) 1996-2000, PostgreSQL, Inc
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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 1.113 2000/04/12 17:15:08 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/trigger.h"
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#include "executor/execdebug.h"
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#include "executor/execdefs.h"
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#include "executor/executor.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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#include "utils/builtins.h"
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#include "utils/syscache.h"
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/* XXX no points for style */
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extern TupleTableSlot *EvalPlanQual(EState *estate, Index rti,
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ItemPointer tid);
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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 EndPlan(Plan *plan,
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EState *estate);
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static TupleTableSlot *ExecutePlan(EState *estate, Plan *plan,
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CmdType operation,
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int offsetTuples,
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int 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, CmdType operation,
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int resultRelation, bool resultIsScanned);
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static void ExecCheckRTPerms(List *rangeTable, CmdType operation,
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int resultRelation, bool resultIsScanned);
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static void ExecCheckRTEPerms(RangeTblEntry *rte, CmdType operation,
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bool isResultRelation, bool resultIsScanned);
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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 (AttrInfo*) which describes the attributes of the tuples to
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* be returned by the query.
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*
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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, 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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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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* the different features supported are:
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* EXEC_RUN: retrieve all tuples in the forward direction
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* EXEC_FOR: retrieve 'count' number of tuples in the forward dir
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* EXEC_BACK: retrieve 'count' number of tuples in the backward dir
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* EXEC_RETONE: return one tuple but don't 'retrieve' it
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* used in postquel function processing
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*
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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, int feature,
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Node *limoffset, Node *limcount)
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{
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CmdType operation;
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Plan *plan;
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TupleTableSlot *result;
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CommandDest dest;
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DestReceiver *destfunc;
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int offset = 0;
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int count = 0;
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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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destfunc = DestToFunction(dest);
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estate->es_processed = 0;
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estate->es_lastoid = InvalidOid;
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/*
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* FIXME: the dest setup function ought to be handed the tuple desc
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* for the tuples to be output, but I'm not quite sure how to get that
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* info at this point. For now, passing NULL is OK because no
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* existing dest setup function actually uses the pointer.
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*/
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(*destfunc->setup) (destfunc, (TupleDesc) NULL);
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/*
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* if given get the offset of the LIMIT clause
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*/
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if (limoffset != NULL)
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{
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Const *coffset;
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Param *poffset;
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ParamListInfo paramLI;
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int i;
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switch (nodeTag(limoffset))
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{
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case T_Const:
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coffset = (Const *) limoffset;
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offset = (int) (coffset->constvalue);
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break;
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case T_Param:
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poffset = (Param *) limoffset;
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paramLI = estate->es_param_list_info;
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if (paramLI == NULL)
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elog(ERROR, "parameter for limit offset not in executor state");
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for (i = 0; paramLI[i].kind != PARAM_INVALID; i++)
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{
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if (paramLI[i].kind == PARAM_NUM && paramLI[i].id == poffset->paramid)
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break;
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}
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if (paramLI[i].kind == PARAM_INVALID)
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elog(ERROR, "parameter for limit offset not in executor state");
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if (paramLI[i].isnull)
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elog(ERROR, "limit offset cannot be NULL value");
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offset = (int) (paramLI[i].value);
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break;
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default:
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elog(ERROR, "unexpected node type %d as limit offset", nodeTag(limoffset));
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}
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if (offset < 0)
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elog(ERROR, "limit offset cannot be negative");
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}
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/*
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* if given get the count of the LIMIT clause
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*/
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if (limcount != NULL)
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{
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Const *ccount;
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Param *pcount;
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ParamListInfo paramLI;
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int i;
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switch (nodeTag(limcount))
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{
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case T_Const:
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ccount = (Const *) limcount;
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count = (int) (ccount->constvalue);
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break;
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case T_Param:
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pcount = (Param *) limcount;
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paramLI = estate->es_param_list_info;
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if (paramLI == NULL)
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elog(ERROR, "parameter for limit count not in executor state");
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for (i = 0; paramLI[i].kind != PARAM_INVALID; i++)
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{
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if (paramLI[i].kind == PARAM_NUM && paramLI[i].id == pcount->paramid)
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break;
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}
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if (paramLI[i].kind == PARAM_INVALID)
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elog(ERROR, "parameter for limit count not in executor state");
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if (paramLI[i].isnull)
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elog(ERROR, "limit count cannot be NULL value");
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count = (int) (paramLI[i].value);
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break;
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default:
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elog(ERROR, "unexpected node type %d as limit count", nodeTag(limcount));
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}
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if (count < 0)
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elog(ERROR, "limit count cannot be negative");
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}
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switch (feature)
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{
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case EXEC_RUN:
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result = ExecutePlan(estate,
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plan,
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operation,
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offset,
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count,
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ForwardScanDirection,
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destfunc);
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break;
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case EXEC_FOR:
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result = ExecutePlan(estate,
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plan,
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operation,
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offset,
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count,
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ForwardScanDirection,
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destfunc);
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break;
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/*
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* retrieve next n "backward" tuples
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*/
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case EXEC_BACK:
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result = ExecutePlan(estate,
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plan,
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operation,
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offset,
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count,
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BackwardScanDirection,
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destfunc);
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break;
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/*
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* return one tuple but don't "retrieve" it. (this is used by
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* the rule manager..) -cim 9/14/89
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*/
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case EXEC_RETONE:
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result = ExecutePlan(estate,
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plan,
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operation,
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0,
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ONE_TUPLE,
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ForwardScanDirection,
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destfunc);
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break;
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default:
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result = NULL;
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elog(DEBUG, "ExecutorRun: Unknown feature %d", feature);
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break;
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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 any execution of any
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* query plan
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*
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* returns (AttrInfo*) which describes the attributes of the tuples to
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* be returned by the query.
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*
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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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/* XXX - clean up some more from ExecutorStart() - er1p */
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if (NULL == estate->es_snapshot)
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{
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/* nothing to free */
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}
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else
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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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}
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if (NULL == estate->es_param_exec_vals)
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{
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/* nothing to free */
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}
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else
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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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List *rangeTable = parseTree->rtable;
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int resultRelation = parseTree->resultRelation;
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bool resultIsScanned = false;
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List *lp;
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/*
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* If we have a result relation, determine whether the result rel is
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* scanned or merely written. If scanned, we will insist on read
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* permission as well as modify permission.
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*/
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if (resultRelation > 0)
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{
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List *qvars = pull_varnos(parseTree->qual);
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List *tvars = pull_varnos((Node *) parseTree->targetList);
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resultIsScanned = (intMember(resultRelation, qvars) ||
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intMember(resultRelation, tvars));
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freeList(qvars);
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freeList(tvars);
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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(rangeTable, operation, resultRelation, resultIsScanned);
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/*
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* Check SELECT FOR UPDATE access rights.
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*/
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foreach(lp, parseTree->rowMark)
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{
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RowMark *rm = lfirst(lp);
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if (!(rm->info & ROW_ACL_FOR_UPDATE))
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continue;
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ExecCheckRTEPerms(rt_fetch(rm->rti, rangeTable),
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CMD_UPDATE, true, false);
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}
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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, operation, resultRelation, resultIsScanned);
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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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* We also need to look at the local rangetables in Append plan nodes,
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* which is pretty bogus --- most likely, those tables should be mentioned
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* in the query's main rangetable. But at the moment, they're not.
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*/
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static void
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ExecCheckPlanPerms(Plan *plan, CmdType operation,
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int resultRelation, bool resultIsScanned)
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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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|
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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, 0, false);
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ExecCheckPlanPerms(subplan->plan, CMD_SELECT, 0, false);
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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, 0, false);
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ExecCheckPlanPerms(subplan->plan, CMD_SELECT, 0, false);
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}
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/* Check lower plan nodes */
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ExecCheckPlanPerms(plan->lefttree, operation,
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resultRelation, resultIsScanned);
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ExecCheckPlanPerms(plan->righttree, operation,
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resultRelation, resultIsScanned);
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|
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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_Append:
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{
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Append *app = (Append *) plan;
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List *appendplans;
|
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if (app->inheritrelid > 0)
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{
|
|
|
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/*
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* Append implements expansion of inheritance; all
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* members of inheritrtable list will be plugged into
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* same RTE slot. Therefore, they are either all
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* result relations or none.
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*/
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List *rtable;
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foreach(rtable, app->inheritrtable)
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{
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ExecCheckRTEPerms((RangeTblEntry *) lfirst(rtable),
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operation,
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(app->inheritrelid == resultRelation),
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resultIsScanned);
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}
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}
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else
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{
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/* Append implements UNION, which must be a SELECT */
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List *rtables;
|
|
|
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foreach(rtables, app->unionrtables)
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{
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ExecCheckRTPerms((List *) lfirst(rtables),
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CMD_SELECT, 0, false);
|
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}
|
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}
|
|
|
|
/* Check appended plans */
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foreach(appendplans, app->appendplans)
|
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{
|
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ExecCheckPlanPerms((Plan *) lfirst(appendplans),
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operation,
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resultRelation,
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resultIsScanned);
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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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}
|
|
}
|
|
|
|
/*
|
|
* ExecCheckRTPerms
|
|
* Check access permissions for all relations listed in a range table.
|
|
*
|
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* If resultRelation is not 0, it is the RT index of the relation to be
|
|
* treated as the result relation. All other relations are assumed to be
|
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* read-only for the query.
|
|
*/
|
|
static void
|
|
ExecCheckRTPerms(List *rangeTable, CmdType operation,
|
|
int resultRelation, bool resultIsScanned)
|
|
{
|
|
int rtindex = 0;
|
|
List *lp;
|
|
|
|
foreach(lp, rangeTable)
|
|
{
|
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RangeTblEntry *rte = lfirst(lp);
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|
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++rtindex;
|
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|
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ExecCheckRTEPerms(rte,
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operation,
|
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(rtindex == resultRelation),
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resultIsScanned);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* ExecCheckRTEPerms
|
|
* Check access permissions for a single RTE.
|
|
*/
|
|
static void
|
|
ExecCheckRTEPerms(RangeTblEntry *rte, CmdType operation,
|
|
bool isResultRelation, bool resultIsScanned)
|
|
{
|
|
char *relName;
|
|
char *userName;
|
|
int32 aclcheck_result;
|
|
|
|
if (rte->skipAcl)
|
|
{
|
|
|
|
/*
|
|
* This happens if the access to this table is due to a view query
|
|
* rewriting - the rewrite handler already checked the permissions
|
|
* against the view owner, so we just skip this entry.
|
|
*/
|
|
return;
|
|
}
|
|
|
|
relName = rte->relname;
|
|
|
|
/*
|
|
* Note: GetPgUserName is presently fast enough that there's no harm
|
|
* in calling it separately for each RTE. If that stops being true,
|
|
* we could call it once in ExecCheckQueryPerms and pass the userName
|
|
* down from there. But for now, no need for the extra clutter.
|
|
*/
|
|
userName = GetPgUserName();
|
|
|
|
#define CHECK(MODE) pg_aclcheck(relName, userName, MODE)
|
|
|
|
if (isResultRelation)
|
|
{
|
|
if (resultIsScanned)
|
|
{
|
|
aclcheck_result = CHECK(ACL_RD);
|
|
if (aclcheck_result != ACLCHECK_OK)
|
|
elog(ERROR, "%s: %s",
|
|
relName, aclcheck_error_strings[aclcheck_result]);
|
|
}
|
|
switch (operation)
|
|
{
|
|
case CMD_INSERT:
|
|
/* Accept either APPEND or WRITE access for this */
|
|
aclcheck_result = CHECK(ACL_AP);
|
|
if (aclcheck_result != ACLCHECK_OK)
|
|
aclcheck_result = CHECK(ACL_WR);
|
|
break;
|
|
case CMD_DELETE:
|
|
case CMD_UPDATE:
|
|
aclcheck_result = CHECK(ACL_WR);
|
|
break;
|
|
default:
|
|
elog(ERROR, "ExecCheckRTEPerms: bogus operation %d",
|
|
operation);
|
|
aclcheck_result = ACLCHECK_OK; /* keep compiler quiet */
|
|
break;
|
|
}
|
|
}
|
|
else
|
|
aclcheck_result = CHECK(ACL_RD);
|
|
|
|
if (aclcheck_result != ACLCHECK_OK)
|
|
elog(ERROR, "%s: %s",
|
|
relName, aclcheck_error_strings[aclcheck_result]);
|
|
}
|
|
|
|
|
|
/* ===============================================================
|
|
* ===============================================================
|
|
static routines follow
|
|
* ===============================================================
|
|
* ===============================================================
|
|
*/
|
|
|
|
typedef struct execRowMark
|
|
{
|
|
Relation relation;
|
|
Index rti;
|
|
char resname[32];
|
|
} execRowMark;
|
|
|
|
typedef struct evalPlanQual
|
|
{
|
|
Plan *plan;
|
|
Index rti;
|
|
EState estate;
|
|
struct evalPlanQual *free;
|
|
} evalPlanQual;
|
|
|
|
/* ----------------------------------------------------------------
|
|
* InitPlan
|
|
*
|
|
* Initializes the query plan: open files, allocate storage
|
|
* and start up the rule manager
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
static TupleDesc
|
|
InitPlan(CmdType operation, Query *parseTree, Plan *plan, EState *estate)
|
|
{
|
|
List *rangeTable;
|
|
int resultRelation;
|
|
Relation intoRelationDesc;
|
|
TupleDesc tupType;
|
|
List *targetList;
|
|
|
|
/*
|
|
* Do permissions checks.
|
|
*/
|
|
#ifndef NO_SECURITY
|
|
ExecCheckQueryPerms(operation, parseTree, plan);
|
|
#endif
|
|
|
|
/*
|
|
* get information from query descriptor
|
|
*/
|
|
rangeTable = parseTree->rtable;
|
|
resultRelation = parseTree->resultRelation;
|
|
|
|
/*
|
|
* initialize the node's execution state
|
|
*/
|
|
estate->es_range_table = rangeTable;
|
|
|
|
/*
|
|
* initialize the BaseId counter so node base_id's are assigned
|
|
* correctly. Someday baseid's will have to be stored someplace other
|
|
* than estate because they should be unique per query planned.
|
|
*/
|
|
estate->es_BaseId = 1;
|
|
|
|
/*
|
|
* initialize result relation stuff
|
|
*/
|
|
|
|
if (resultRelation != 0 && operation != CMD_SELECT)
|
|
{
|
|
|
|
/*
|
|
* if we have a result relation, open it and initialize the result
|
|
* relation info stuff.
|
|
*/
|
|
RelationInfo *resultRelationInfo;
|
|
Index resultRelationIndex;
|
|
RangeTblEntry *rtentry;
|
|
Oid resultRelationOid;
|
|
Relation resultRelationDesc;
|
|
|
|
resultRelationIndex = resultRelation;
|
|
rtentry = rt_fetch(resultRelationIndex, rangeTable);
|
|
resultRelationOid = rtentry->relid;
|
|
resultRelationDesc = heap_open(resultRelationOid, RowExclusiveLock);
|
|
|
|
if (resultRelationDesc->rd_rel->relkind == RELKIND_SEQUENCE)
|
|
elog(ERROR, "You can't change sequence relation %s",
|
|
RelationGetRelationName(resultRelationDesc));
|
|
|
|
resultRelationInfo = makeNode(RelationInfo);
|
|
resultRelationInfo->ri_RangeTableIndex = resultRelationIndex;
|
|
resultRelationInfo->ri_RelationDesc = resultRelationDesc;
|
|
resultRelationInfo->ri_NumIndices = 0;
|
|
resultRelationInfo->ri_IndexRelationDescs = NULL;
|
|
resultRelationInfo->ri_IndexRelationInfo = 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(resultRelationOid, resultRelationInfo);
|
|
|
|
estate->es_result_relation_info = resultRelationInfo;
|
|
}
|
|
else
|
|
{
|
|
|
|
/*
|
|
* if no result relation, then set state appropriately
|
|
*/
|
|
estate->es_result_relation_info = NULL;
|
|
}
|
|
|
|
/*
|
|
* Have to lock relations selected for update
|
|
*/
|
|
estate->es_rowMark = NULL;
|
|
if (parseTree->rowMark != NULL)
|
|
{
|
|
List *l;
|
|
|
|
foreach(l, parseTree->rowMark)
|
|
{
|
|
RowMark *rm = lfirst(l);
|
|
Oid relid;
|
|
Relation relation;
|
|
execRowMark *erm;
|
|
|
|
if (!(rm->info & ROW_MARK_FOR_UPDATE))
|
|
continue;
|
|
relid = rt_fetch(rm->rti, rangeTable)->relid;
|
|
relation = heap_open(relid, RowShareLock);
|
|
erm = (execRowMark *) palloc(sizeof(execRowMark));
|
|
erm->relation = relation;
|
|
erm->rti = rm->rti;
|
|
sprintf(erm->resname, "ctid%u", rm->rti);
|
|
estate->es_rowMark = lappend(estate->es_rowMark, erm);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* initialize the executor "tuple" table.
|
|
*/
|
|
{
|
|
int nSlots = ExecCountSlotsNode(plan);
|
|
TupleTable tupleTable = ExecCreateTupleTable(nSlots + 10); /* why add ten? - jolly */
|
|
|
|
estate->es_tupleTable = tupleTable;
|
|
}
|
|
|
|
/*
|
|
* 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 */
|
|
targetList = plan->targetlist;
|
|
|
|
/*
|
|
* Now that we have the target list, 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, 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)
|
|
{
|
|
JunkFilter *j = ExecInitJunkFilter(targetList, tupType);
|
|
|
|
estate->es_junkFilter = j;
|
|
|
|
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, parseTree->isTemp);
|
|
|
|
FreeTupleDesc(tupdesc);
|
|
|
|
/*
|
|
* Advance command counter so that the newly-created
|
|
* relation's catalog tuples will be visible to heap_open.
|
|
*/
|
|
CommandCounterIncrement();
|
|
|
|
intoRelationDesc = heap_open(intoRelationId,
|
|
AccessExclusiveLock);
|
|
}
|
|
}
|
|
}
|
|
|
|
estate->es_into_relation_descriptor = intoRelationDesc;
|
|
|
|
estate->es_origPlan = plan;
|
|
estate->es_evalPlanQual = NULL;
|
|
estate->es_evTuple = NULL;
|
|
estate->es_useEvalPlan = false;
|
|
|
|
return tupType;
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* EndPlan
|
|
*
|
|
* Cleans up the query plan -- closes files and free up storages
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
static void
|
|
EndPlan(Plan *plan, EState *estate)
|
|
{
|
|
RelationInfo *resultRelationInfo;
|
|
Relation intoRelationDesc;
|
|
List *l;
|
|
|
|
/*
|
|
* get information from state
|
|
*/
|
|
resultRelationInfo = estate->es_result_relation_info;
|
|
intoRelationDesc = estate->es_into_relation_descriptor;
|
|
|
|
/*
|
|
* shut down any PlanQual processing we were doing
|
|
*/
|
|
if (estate->es_evalPlanQual != NULL)
|
|
EndEvalPlanQual(estate);
|
|
|
|
/*
|
|
* shut down the query
|
|
*/
|
|
ExecEndNode(plan, plan);
|
|
|
|
/*
|
|
* destroy the executor "tuple" table.
|
|
*/
|
|
{
|
|
TupleTable tupleTable = (TupleTable) estate->es_tupleTable;
|
|
|
|
ExecDropTupleTable(tupleTable, true);
|
|
estate->es_tupleTable = NULL;
|
|
}
|
|
|
|
/*
|
|
* close the result relations if necessary, but hold locks on them
|
|
* until xact commit
|
|
*/
|
|
if (resultRelationInfo != NULL)
|
|
{
|
|
Relation resultRelationDesc;
|
|
|
|
resultRelationDesc = resultRelationInfo->ri_RelationDesc;
|
|
heap_close(resultRelationDesc, NoLock);
|
|
|
|
/*
|
|
* close indices on the result relation
|
|
*/
|
|
ExecCloseIndices(resultRelationInfo);
|
|
}
|
|
|
|
/*
|
|
* close the "into" relation if necessary, again keeping lock
|
|
*/
|
|
if (intoRelationDesc != NULL)
|
|
heap_close(intoRelationDesc, NoLock);
|
|
|
|
/*
|
|
* 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 'tupleCount' tuples in the
|
|
* direction specified.
|
|
* Retrieves all tuples if tupleCount is 0
|
|
*
|
|
* result is either a slot containing a tuple in the case
|
|
* of a RETRIEVE or NULL otherwise.
|
|
*
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
|
|
/* 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,
|
|
int offsetTuples,
|
|
int numberTuples,
|
|
ScanDirection direction,
|
|
DestReceiver *destfunc)
|
|
{
|
|
JunkFilter *junkfilter;
|
|
TupleTableSlot *slot;
|
|
ItemPointer tupleid = NULL;
|
|
ItemPointerData tuple_ctid;
|
|
int 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 (;;)
|
|
{
|
|
|
|
/*
|
|
* Execute the plan and obtain a tuple
|
|
*/
|
|
/* at the top level, the parent of a plan (2nd arg) is itself */
|
|
lnext: ;
|
|
if (estate->es_useEvalPlan)
|
|
{
|
|
slot = EvalPlanQualNext(estate);
|
|
if (TupIsNull(slot))
|
|
slot = ExecProcNode(plan, plan);
|
|
}
|
|
else
|
|
slot = ExecProcNode(plan, plan);
|
|
|
|
/*
|
|
* 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;
|
|
}
|
|
|
|
/*
|
|
* For now we completely execute the plan and skip result tuples
|
|
* if requested by LIMIT offset. Finally we should try to do it in
|
|
* deeper levels if possible (during index scan) - Jan
|
|
*/
|
|
if (offsetTuples > 0)
|
|
{
|
|
--offsetTuples;
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* if we have a junk filter, then project a new tuple with the
|
|
* junk removed.
|
|
*
|
|
* Store this new "clean" tuple in the place of the original tuple.
|
|
*
|
|
* 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!");
|
|
|
|
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 != NULL)
|
|
{
|
|
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);
|
|
|
|
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");
|
|
return (NULL);
|
|
}
|
|
else 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 have 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 */
|
|
slot, /* destination 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(DEBUG, "ExecutePlan: unknown operation in queryDesc");
|
|
result = NULL;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* check our tuple count.. if we've returned the proper number
|
|
* then return, else loop again and process more tuples..
|
|
*/
|
|
current_tuple_count += 1;
|
|
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;
|
|
RelationInfo *resultRelationInfo;
|
|
Relation resultRelationDesc;
|
|
int numIndices;
|
|
Oid newId;
|
|
|
|
/*
|
|
* get the heap tuple out of the tuple table slot
|
|
*/
|
|
tuple = slot->val;
|
|
|
|
/*
|
|
* get information on the result relation
|
|
*/
|
|
resultRelationInfo = estate->es_result_relation_info;
|
|
resultRelationDesc = resultRelationInfo->ri_RelationDesc;
|
|
|
|
/*
|
|
* have to add code to preform unique checking here. cim -12/1/89
|
|
*/
|
|
|
|
/* BEFORE ROW INSERT Triggers */
|
|
if (resultRelationDesc->trigdesc &&
|
|
resultRelationDesc->trigdesc->n_before_row[TRIGGER_EVENT_INSERT] > 0)
|
|
{
|
|
HeapTuple newtuple;
|
|
|
|
newtuple = ExecBRInsertTriggers(resultRelationDesc, tuple);
|
|
|
|
if (newtuple == NULL) /* "do nothing" */
|
|
return;
|
|
|
|
if (newtuple != tuple) /* modified by Trigger(s) */
|
|
{
|
|
Assert(slot->ttc_shouldFree);
|
|
heap_freetuple(tuple);
|
|
slot->val = tuple = newtuple;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Check the constraints of a tuple
|
|
*/
|
|
|
|
if (resultRelationDesc->rd_att->constr)
|
|
ExecConstraints("ExecAppend", resultRelationDesc, tuple, estate);
|
|
|
|
/*
|
|
* insert the tuple
|
|
*/
|
|
newId = heap_insert(resultRelationDesc, /* relation desc */
|
|
tuple); /* heap tuple */
|
|
IncrAppended();
|
|
|
|
/*
|
|
* 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 = resultRelationInfo->ri_NumIndices;
|
|
if (numIndices > 0)
|
|
ExecInsertIndexTuples(slot, &(tuple->t_self), estate, false);
|
|
(estate->es_processed)++;
|
|
estate->es_lastoid = newId;
|
|
|
|
/* AFTER ROW INSERT Triggers */
|
|
if (resultRelationDesc->trigdesc)
|
|
ExecARInsertTriggers(resultRelationDesc, tuple);
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecDelete
|
|
*
|
|
* DELETE is like append, we delete the tuple and its
|
|
* index tuples.
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
static void
|
|
ExecDelete(TupleTableSlot *slot,
|
|
ItemPointer tupleid,
|
|
EState *estate)
|
|
{
|
|
RelationInfo *resultRelationInfo;
|
|
Relation resultRelationDesc;
|
|
ItemPointerData ctid;
|
|
int result;
|
|
|
|
/*
|
|
* get the result relation information
|
|
*/
|
|
resultRelationInfo = estate->es_result_relation_info;
|
|
resultRelationDesc = resultRelationInfo->ri_RelationDesc;
|
|
|
|
/* BEFORE ROW DELETE Triggers */
|
|
if (resultRelationDesc->trigdesc &&
|
|
resultRelationDesc->trigdesc->n_before_row[TRIGGER_EVENT_DELETE] > 0)
|
|
{
|
|
bool dodelete;
|
|
|
|
dodelete = ExecBRDeleteTriggers(estate, 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,
|
|
resultRelationInfo->ri_RangeTableIndex, &ctid);
|
|
|
|
if (!TupIsNull(epqslot))
|
|
{
|
|
*tupleid = ctid;
|
|
goto ldelete;
|
|
}
|
|
}
|
|
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 (resultRelationDesc->trigdesc)
|
|
ExecARDeleteTriggers(estate, 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;
|
|
RelationInfo *resultRelationInfo;
|
|
Relation resultRelationDesc;
|
|
ItemPointerData ctid;
|
|
int result;
|
|
int numIndices;
|
|
|
|
/*
|
|
* abort the operation if not running transactions
|
|
*/
|
|
if (IsBootstrapProcessingMode())
|
|
{
|
|
elog(DEBUG, "ExecReplace: replace can't run without transactions");
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* get the heap tuple out of the tuple table slot
|
|
*/
|
|
tuple = slot->val;
|
|
|
|
/*
|
|
* get the result relation information
|
|
*/
|
|
resultRelationInfo = estate->es_result_relation_info;
|
|
resultRelationDesc = resultRelationInfo->ri_RelationDesc;
|
|
|
|
/*
|
|
* have to add code to preform unique checking here. in the event of
|
|
* unique tuples, this becomes a deletion of the original tuple
|
|
* affected by the replace. cim -12/1/89
|
|
*/
|
|
|
|
/* BEFORE ROW UPDATE Triggers */
|
|
if (resultRelationDesc->trigdesc &&
|
|
resultRelationDesc->trigdesc->n_before_row[TRIGGER_EVENT_UPDATE] > 0)
|
|
{
|
|
HeapTuple newtuple;
|
|
|
|
newtuple = ExecBRUpdateTriggers(estate, tupleid, tuple);
|
|
|
|
if (newtuple == NULL) /* "do nothing" */
|
|
return;
|
|
|
|
if (newtuple != tuple) /* modified by Trigger(s) */
|
|
{
|
|
Assert(slot->ttc_shouldFree);
|
|
heap_freetuple(tuple);
|
|
slot->val = tuple = newtuple;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Check the constraints of a tuple
|
|
*/
|
|
|
|
if (resultRelationDesc->rd_att->constr)
|
|
ExecConstraints("ExecReplace", resultRelationDesc, tuple, estate);
|
|
|
|
/*
|
|
* replace the heap tuple
|
|
*/
|
|
lreplace:;
|
|
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,
|
|
resultRelationInfo->ri_RangeTableIndex, &ctid);
|
|
|
|
if (!TupIsNull(epqslot))
|
|
{
|
|
*tupleid = ctid;
|
|
tuple = ExecRemoveJunk(estate->es_junkFilter, epqslot);
|
|
slot = ExecStoreTuple(tuple, slot, InvalidBuffer, true);
|
|
goto lreplace;
|
|
}
|
|
}
|
|
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 vaccuum
|
|
* deamon.. 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 = resultRelationInfo->ri_NumIndices;
|
|
if (numIndices > 0)
|
|
ExecInsertIndexTuples(slot, &(tuple->t_self), estate, true);
|
|
|
|
/* AFTER ROW UPDATE Triggers */
|
|
if (resultRelationDesc->trigdesc)
|
|
ExecARUpdateTriggers(estate, tupleid, tuple);
|
|
}
|
|
|
|
#ifdef NOT_USED
|
|
static HeapTuple
|
|
ExecAttrDefault(Relation rel, HeapTuple tuple)
|
|
{
|
|
int ndef = rel->rd_att->constr->num_defval;
|
|
AttrDefault *attrdef = rel->rd_att->constr->defval;
|
|
ExprContext *econtext = makeNode(ExprContext);
|
|
HeapTuple newtuple;
|
|
Node *expr;
|
|
bool isnull;
|
|
bool isdone;
|
|
Datum val;
|
|
Datum *replValue = NULL;
|
|
char *replNull = NULL;
|
|
char *repl = NULL;
|
|
int i;
|
|
|
|
econtext->ecxt_scantuple = NULL; /* scan tuple slot */
|
|
econtext->ecxt_innertuple = NULL; /* inner tuple slot */
|
|
econtext->ecxt_outertuple = NULL; /* outer tuple slot */
|
|
econtext->ecxt_relation = NULL; /* relation */
|
|
econtext->ecxt_relid = 0; /* relid */
|
|
econtext->ecxt_param_list_info = NULL; /* param list info */
|
|
econtext->ecxt_param_exec_vals = NULL; /* exec param values */
|
|
econtext->ecxt_range_table = NULL; /* range table */
|
|
for (i = 0; i < ndef; i++)
|
|
{
|
|
if (!heap_attisnull(tuple, attrdef[i].adnum))
|
|
continue;
|
|
expr = (Node *) stringToNode(attrdef[i].adbin);
|
|
|
|
val = ExecEvalExpr(expr, econtext, &isnull, &isdone);
|
|
|
|
pfree(expr);
|
|
|
|
if (isnull)
|
|
continue;
|
|
|
|
if (repl == NULL)
|
|
{
|
|
repl = (char *) palloc(rel->rd_att->natts * sizeof(char));
|
|
replNull = (char *) palloc(rel->rd_att->natts * sizeof(char));
|
|
replValue = (Datum *) palloc(rel->rd_att->natts * sizeof(Datum));
|
|
MemSet(repl, ' ', rel->rd_att->natts * sizeof(char));
|
|
}
|
|
|
|
repl[attrdef[i].adnum - 1] = 'r';
|
|
replNull[attrdef[i].adnum - 1] = ' ';
|
|
replValue[attrdef[i].adnum - 1] = val;
|
|
|
|
}
|
|
|
|
pfree(econtext);
|
|
|
|
if (repl == NULL)
|
|
return tuple;
|
|
|
|
newtuple = heap_modifytuple(tuple, rel, replValue, replNull, repl);
|
|
|
|
pfree(repl);
|
|
heap_freetuple(tuple);
|
|
pfree(replNull);
|
|
pfree(replValue);
|
|
|
|
return newtuple;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
static char *
|
|
ExecRelCheck(Relation rel, HeapTuple tuple, EState *estate)
|
|
{
|
|
int ncheck = rel->rd_att->constr->num_check;
|
|
ConstrCheck *check = rel->rd_att->constr->check;
|
|
ExprContext *econtext = makeNode(ExprContext);
|
|
TupleTableSlot *slot = makeNode(TupleTableSlot);
|
|
RangeTblEntry *rte = makeNode(RangeTblEntry);
|
|
List *rtlist;
|
|
List *qual;
|
|
int i;
|
|
|
|
slot->val = tuple;
|
|
slot->ttc_shouldFree = false;
|
|
slot->ttc_descIsNew = true;
|
|
slot->ttc_tupleDescriptor = rel->rd_att;
|
|
slot->ttc_buffer = InvalidBuffer;
|
|
slot->ttc_whichplan = -1;
|
|
rte->relname = RelationGetRelationName(rel);
|
|
rte->ref = makeNode(Attr);
|
|
rte->ref->relname = rte->relname;
|
|
rte->relid = RelationGetRelid(rel);
|
|
/* inh, inFromCl, inJoinSet, skipAcl won't be used, leave them zero */
|
|
rtlist = lcons(rte, NIL);
|
|
econtext->ecxt_scantuple = slot; /* scan tuple slot */
|
|
econtext->ecxt_innertuple = NULL; /* inner tuple slot */
|
|
econtext->ecxt_outertuple = NULL; /* outer tuple slot */
|
|
econtext->ecxt_relation = rel; /* relation */
|
|
econtext->ecxt_relid = 0; /* relid */
|
|
econtext->ecxt_param_list_info = NULL; /* param list info */
|
|
econtext->ecxt_param_exec_vals = NULL; /* exec param values */
|
|
econtext->ecxt_range_table = rtlist; /* range table */
|
|
|
|
if (estate->es_result_relation_constraints == NULL)
|
|
{
|
|
estate->es_result_relation_constraints =
|
|
(List **) palloc(ncheck * sizeof(List *));
|
|
|
|
for (i = 0; i < ncheck; i++)
|
|
{
|
|
qual = (List *) stringToNode(check[i].ccbin);
|
|
estate->es_result_relation_constraints[i] = qual;
|
|
}
|
|
}
|
|
|
|
for (i = 0; i < ncheck; i++)
|
|
{
|
|
qual = estate->es_result_relation_constraints[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;
|
|
}
|
|
|
|
pfree(slot);
|
|
pfree(rte);
|
|
pfree(rtlist);
|
|
pfree(econtext);
|
|
|
|
return (char *) NULL;
|
|
|
|
}
|
|
|
|
void
|
|
ExecConstraints(char *caller, Relation rel, HeapTuple tuple, EState *estate)
|
|
{
|
|
|
|
Assert(rel->rd_att->constr);
|
|
|
|
if (rel->rd_att->constr->has_not_null)
|
|
{
|
|
int attrChk;
|
|
|
|
for (attrChk = 1; attrChk <= rel->rd_att->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 (rel->rd_att->constr->num_check > 0)
|
|
{
|
|
char *failed;
|
|
|
|
if ((failed = ExecRelCheck(rel, tuple, estate)) != NULL)
|
|
elog(ERROR, "%s: rejected due to CHECK constraint %s", caller, failed);
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
TupleTableSlot *
|
|
EvalPlanQual(EState *estate, Index rti, ItemPointer tid)
|
|
{
|
|
evalPlanQual *epq = (evalPlanQual *) estate->es_evalPlanQual;
|
|
evalPlanQual *oldepq;
|
|
EState *epqstate = NULL;
|
|
Relation relation;
|
|
Buffer buffer;
|
|
HeapTupleData tuple;
|
|
bool endNode = true;
|
|
|
|
Assert(rti != 0);
|
|
|
|
if (epq != NULL && epq->rti == 0)
|
|
{
|
|
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
|
|
{
|
|
/* pop previous PlanQual from the stack */
|
|
epqstate = &(epq->estate);
|
|
oldepq = (evalPlanQual *) epqstate->es_evalPlanQual;
|
|
Assert(oldepq->rti != 0);
|
|
/* stop execution */
|
|
ExecEndNode(epq->plan, epq->plan);
|
|
epqstate->es_tupleTable->next = 0;
|
|
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;
|
|
} while (epq->rti != rti);
|
|
estate->es_evalPlanQual = (Pointer) epq;
|
|
}
|
|
|
|
/*
|
|
* 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));
|
|
/* Init EState */
|
|
epqstate = &(newepq->estate);
|
|
memset(epqstate, 0, sizeof(EState));
|
|
epqstate->type = T_EState;
|
|
epqstate->es_direction = ForwardScanDirection;
|
|
epqstate->es_snapshot = estate->es_snapshot;
|
|
epqstate->es_range_table = estate->es_range_table;
|
|
epqstate->es_param_list_info = estate->es_param_list_info;
|
|
if (estate->es_origPlan->nParamExec > 0)
|
|
epqstate->es_param_exec_vals = (ParamExecData *)
|
|
palloc(estate->es_origPlan->nParamExec *
|
|
sizeof(ParamExecData));
|
|
epqstate->es_tupleTable =
|
|
ExecCreateTupleTable(estate->es_tupleTable->size);
|
|
/* ... rest */
|
|
newepq->plan = copyObject(estate->es_origPlan);
|
|
newepq->free = NULL;
|
|
epqstate->es_evTupleNull = (bool *)
|
|
palloc(length(estate->es_range_table) * sizeof(bool));
|
|
if (epq == NULL) /* first call */
|
|
{
|
|
epqstate->es_evTuple = (HeapTuple *)
|
|
palloc(length(estate->es_range_table) * sizeof(HeapTuple));
|
|
memset(epqstate->es_evTuple, 0,
|
|
length(estate->es_range_table) * sizeof(HeapTuple));
|
|
}
|
|
else
|
|
epqstate->es_evTuple = epq->estate.es_evTuple;
|
|
}
|
|
else
|
|
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;
|
|
}
|
|
|
|
epqstate = &(epq->estate);
|
|
|
|
/*
|
|
* Ok - we're requested for the same RTE (-:)). I'm not sure about
|
|
* ability to use ExecReScan instead of ExecInitNode, so...
|
|
*/
|
|
if (endNode)
|
|
{
|
|
ExecEndNode(epq->plan, epq->plan);
|
|
epqstate->es_tupleTable->next = 0;
|
|
}
|
|
|
|
/* free old RTE' tuple */
|
|
if (epqstate->es_evTuple[epq->rti - 1] != NULL)
|
|
{
|
|
heap_freetuple(epqstate->es_evTuple[epq->rti - 1]);
|
|
epqstate->es_evTuple[epq->rti - 1] = NULL;
|
|
}
|
|
|
|
/* ** fetch tid 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;
|
|
|
|
foreach(l, estate->es_rowMark)
|
|
{
|
|
if (((execRowMark *) lfirst(l))->rti == rti)
|
|
break;
|
|
}
|
|
relation = ((execRowMark *) lfirst(l))->relation;
|
|
}
|
|
tuple.t_self = *tid;
|
|
for (;;)
|
|
{
|
|
heap_fetch(relation, SnapshotDirty, &tuple, &buffer);
|
|
if (tuple.t_data != NULL)
|
|
{
|
|
TransactionId xwait = SnapshotDirty->xmax;
|
|
|
|
if (TransactionIdIsValid(SnapshotDirty->xmin))
|
|
{
|
|
elog(NOTICE, "EvalPlanQual: t_xmin is uncommitted ?!");
|
|
Assert(!TransactionIdIsValid(SnapshotDirty->xmin));
|
|
elog(ERROR, "Aborting this transaction");
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
}
|
|
|
|
/*
|
|
* Nice! We got tuple - now copy it.
|
|
*/
|
|
if (epqstate->es_evTuple[epq->rti - 1] != NULL)
|
|
heap_freetuple(epqstate->es_evTuple[epq->rti - 1]);
|
|
epqstate->es_evTuple[epq->rti - 1] = heap_copytuple(&tuple);
|
|
ReleaseBuffer(buffer);
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Ops! 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))))
|
|
{
|
|
tuple.t_self = SnapshotDirty->tid; /* updated ... */
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Deleted or updated by this transaction. Do not (re-)start
|
|
* execution of this PQ. Continue previous PQ.
|
|
*/
|
|
oldepq = (evalPlanQual *) epqstate->es_evalPlanQual;
|
|
if (oldepq != NULL)
|
|
{
|
|
Assert(oldepq->rti != 0);
|
|
/* push current PQ to freePQ stack */
|
|
oldepq->free = epq;
|
|
epq = oldepq;
|
|
epqstate = &(epq->estate);
|
|
estate->es_evalPlanQual = (Pointer) epq;
|
|
}
|
|
else
|
|
{
|
|
epq->rti = 0; /* this is the first (oldest) */
|
|
estate->es_useEvalPlan = false; /* PQ - mark as free and */
|
|
return (NULL); /* continue Query execution */
|
|
}
|
|
}
|
|
|
|
if (estate->es_origPlan->nParamExec > 0)
|
|
memset(epqstate->es_param_exec_vals, 0,
|
|
estate->es_origPlan->nParamExec * sizeof(ParamExecData));
|
|
memset(epqstate->es_evTupleNull, false,
|
|
length(estate->es_range_table) * sizeof(bool));
|
|
Assert(epqstate->es_tupleTable->next == 0);
|
|
ExecInitNode(epq->plan, epqstate, NULL);
|
|
|
|
/*
|
|
* For UPDATE/DELETE we have to return tid of actual row we're
|
|
* executing PQ for.
|
|
*/
|
|
*tid = tuple.t_self;
|
|
|
|
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, epq->plan);
|
|
|
|
/*
|
|
* No more tuples for this PQ. Continue previous one.
|
|
*/
|
|
if (TupIsNull(slot))
|
|
{
|
|
ExecEndNode(epq->plan, epq->plan);
|
|
epqstate->es_tupleTable->next = 0;
|
|
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 (;;)
|
|
{
|
|
ExecEndNode(epq->plan, epq->plan);
|
|
epqstate->es_tupleTable->next = 0;
|
|
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;
|
|
}
|
|
}
|