mirror of
https://git.postgresql.org/git/postgresql.git
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bedb78d386
to eliminate unnecessary deadlocks. This commit adds SELECT ... FOR SHARE paralleling SELECT ... FOR UPDATE. The implementation uses a new SLRU data structure (managed much like pg_subtrans) to represent multiple- transaction-ID sets. When more than one transaction is holding a shared lock on a particular row, we create a MultiXactId representing that set of transactions and store its ID in the row's XMAX. This scheme allows an effectively unlimited number of row locks, just as we did before, while not costing any extra overhead except when a shared lock actually has to be shared. Still TODO: use the regular lock manager to control the grant order when multiple backends are waiting for a row lock. Alvaro Herrera and Tom Lane.
2163 lines
56 KiB
C
2163 lines
56 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* The old ExecutorMain() has been replaced by ExecutorStart(),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 is required as an argument.
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*
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* ExecutorStart() must be called at the beginning of 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) 1996-2005, 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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* $PostgreSQL: pgsql/src/backend/executor/execMain.c,v 1.247 2005/04/28 21:47:12 tgl 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 "catalog/namespace.h"
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#include "commands/tablecmds.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/instrument.h"
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#include "miscadmin.h"
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#include "optimizer/clauses.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/guc.h"
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#include "utils/lsyscache.h"
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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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Index rti;
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EState *estate;
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PlanState *planstate;
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struct evalPlanQual *next; /* stack of active PlanQual plans */
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struct evalPlanQual *free; /* list of free PlanQual plans */
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} evalPlanQual;
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/* decls for local routines only used within this module */
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static void InitPlan(QueryDesc *queryDesc, bool explainOnly);
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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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bool doInstrument);
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static TupleTableSlot *ExecutePlan(EState *estate, PlanState *planstate,
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CmdType operation,
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long numberTuples,
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ScanDirection direction,
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DestReceiver *dest);
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static void ExecSelect(TupleTableSlot *slot,
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DestReceiver *dest,
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EState *estate);
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static void ExecInsert(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 ExecUpdate(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 ExecCheckRTEPerms(RangeTblEntry *rte);
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static void ExecCheckXactReadOnly(Query *parsetree);
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static void EvalPlanQualStart(evalPlanQual *epq, EState *estate,
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evalPlanQual *priorepq);
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static void EvalPlanQualStop(evalPlanQual *epq);
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/* end of local decls */
|
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|
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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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* Takes a QueryDesc previously created by CreateQueryDesc (it's not real
|
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* clear why we bother to separate the two functions, but...). The tupDesc
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* field of the QueryDesc is filled in to describe the tuples that will be
|
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* returned, and the internal fields (estate and planstate) are set up.
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*
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* If explainOnly is true, we are not actually intending to run the plan,
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* only to set up for EXPLAIN; so skip unwanted side-effects.
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*
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* NB: the CurrentMemoryContext when this is called will become the parent
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* of the per-query context used for this Executor invocation.
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* ----------------------------------------------------------------
|
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*/
|
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void
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ExecutorStart(QueryDesc *queryDesc, bool explainOnly)
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{
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EState *estate;
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MemoryContext oldcontext;
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|
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/* sanity checks: queryDesc must not be started already */
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Assert(queryDesc != NULL);
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Assert(queryDesc->estate == NULL);
|
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|
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/*
|
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* If the transaction is read-only, we need to check if any writes are
|
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* planned to non-temporary tables.
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*/
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if (XactReadOnly && !explainOnly)
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ExecCheckXactReadOnly(queryDesc->parsetree);
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|
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/*
|
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* Build EState, switch into per-query memory context for startup.
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*/
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estate = CreateExecutorState();
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queryDesc->estate = estate;
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oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
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/*
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* Fill in parameters, if any, from queryDesc
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*/
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estate->es_param_list_info = queryDesc->params;
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if (queryDesc->plantree->nParamExec > 0)
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estate->es_param_exec_vals = (ParamExecData *)
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palloc0(queryDesc->plantree->nParamExec * sizeof(ParamExecData));
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|
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/*
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|
* Copy other important information into the EState
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*/
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estate->es_snapshot = queryDesc->snapshot;
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estate->es_crosscheck_snapshot = queryDesc->crosscheck_snapshot;
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estate->es_instrument = queryDesc->doInstrument;
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/*
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* Initialize the plan state tree
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*/
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InitPlan(queryDesc, explainOnly);
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MemoryContextSwitchTo(oldcontext);
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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 portal limit, i.e., run to
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* completion.
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|
*
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|
* ----------------------------------------------------------------
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*/
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TupleTableSlot *
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ExecutorRun(QueryDesc *queryDesc,
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|
ScanDirection direction, long count)
|
|
{
|
|
EState *estate;
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CmdType operation;
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|
DestReceiver *dest;
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TupleTableSlot *result;
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MemoryContext oldcontext;
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|
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/* sanity checks */
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Assert(queryDesc != NULL);
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estate = queryDesc->estate;
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Assert(estate != NULL);
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/*
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* Switch into per-query memory context
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*/
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oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
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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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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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(*dest->rStartup) (dest, operation, 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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queryDesc->planstate,
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operation,
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count,
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direction,
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dest);
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/*
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* shutdown receiver
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*/
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(*dest->rShutdown) (dest);
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MemoryContextSwitchTo(oldcontext);
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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)
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{
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EState *estate;
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MemoryContext oldcontext;
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/* sanity checks */
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Assert(queryDesc != NULL);
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estate = queryDesc->estate;
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Assert(estate != NULL);
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/*
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* Switch into per-query memory context to run ExecEndPlan
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*/
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oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
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ExecEndPlan(queryDesc->planstate, estate);
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/*
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* Must switch out of context before destroying it
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*/
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MemoryContextSwitchTo(oldcontext);
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/*
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* Release EState and per-query memory context. This should release
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* everything the executor has allocated.
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*/
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FreeExecutorState(estate);
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/* Reset queryDesc fields that no longer point to anything */
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queryDesc->tupDesc = NULL;
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queryDesc->estate = NULL;
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queryDesc->planstate = NULL;
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}
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/* ----------------------------------------------------------------
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* ExecutorRewind
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*
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* This routine may be called on an open queryDesc to rewind it
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* to the start.
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* ----------------------------------------------------------------
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*/
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void
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ExecutorRewind(QueryDesc *queryDesc)
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{
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EState *estate;
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MemoryContext oldcontext;
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/* sanity checks */
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Assert(queryDesc != NULL);
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estate = queryDesc->estate;
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Assert(estate != NULL);
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/* It's probably not sensible to rescan updating queries */
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Assert(queryDesc->operation == CMD_SELECT);
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/*
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* Switch into per-query memory context
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*/
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oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
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/*
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* rescan plan
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*/
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ExecReScan(queryDesc->planstate, NULL);
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MemoryContextSwitchTo(oldcontext);
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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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void
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ExecCheckRTPerms(List *rangeTable)
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{
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ListCell *l;
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foreach(l, rangeTable)
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{
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RangeTblEntry *rte = lfirst(l);
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ExecCheckRTEPerms(rte);
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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)
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{
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AclMode requiredPerms;
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Oid relOid;
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AclId userid;
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/*
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* If it's a subquery, recursively examine its rangetable.
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*/
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if (rte->rtekind == RTE_SUBQUERY)
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{
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ExecCheckRTPerms(rte->subquery->rtable);
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return;
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}
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|
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/*
|
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* Otherwise, only plain-relation RTEs need to be checked here.
|
|
* Function RTEs are checked by init_fcache when the function is
|
|
* prepared for execution. Join and special RTEs need no checks.
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|
*/
|
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if (rte->rtekind != RTE_RELATION)
|
|
return;
|
|
|
|
/*
|
|
* No work if requiredPerms is empty.
|
|
*/
|
|
requiredPerms = rte->requiredPerms;
|
|
if (requiredPerms == 0)
|
|
return;
|
|
|
|
relOid = rte->relid;
|
|
|
|
/*
|
|
* userid to check as: current user unless we have a setuid
|
|
* indication.
|
|
*
|
|
* Note: GetUserId() 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 ExecCheckRTPerms and pass the userid down
|
|
* from there. But for now, no need for the extra clutter.
|
|
*/
|
|
userid = rte->checkAsUser ? rte->checkAsUser : GetUserId();
|
|
|
|
/*
|
|
* We must have *all* the requiredPerms bits, so use aclmask not
|
|
* aclcheck.
|
|
*/
|
|
if (pg_class_aclmask(relOid, userid, requiredPerms, ACLMASK_ALL)
|
|
!= requiredPerms)
|
|
aclcheck_error(ACLCHECK_NO_PRIV, ACL_KIND_CLASS,
|
|
get_rel_name(relOid));
|
|
}
|
|
|
|
/*
|
|
* Check that the query does not imply any writes to non-temp tables.
|
|
*/
|
|
static void
|
|
ExecCheckXactReadOnly(Query *parsetree)
|
|
{
|
|
ListCell *l;
|
|
|
|
/*
|
|
* CREATE TABLE AS or SELECT INTO?
|
|
*
|
|
* XXX should we allow this if the destination is temp?
|
|
*/
|
|
if (parsetree->into != NULL)
|
|
goto fail;
|
|
|
|
/* Fail if write permissions are requested on any non-temp table */
|
|
foreach(l, parsetree->rtable)
|
|
{
|
|
RangeTblEntry *rte = lfirst(l);
|
|
|
|
if (rte->rtekind == RTE_SUBQUERY)
|
|
{
|
|
ExecCheckXactReadOnly(rte->subquery);
|
|
continue;
|
|
}
|
|
|
|
if (rte->rtekind != RTE_RELATION)
|
|
continue;
|
|
|
|
if ((rte->requiredPerms & (~ACL_SELECT)) == 0)
|
|
continue;
|
|
|
|
if (isTempNamespace(get_rel_namespace(rte->relid)))
|
|
continue;
|
|
|
|
goto fail;
|
|
}
|
|
|
|
return;
|
|
|
|
fail:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_READ_ONLY_SQL_TRANSACTION),
|
|
errmsg("transaction is read-only")));
|
|
}
|
|
|
|
|
|
/* ----------------------------------------------------------------
|
|
* InitPlan
|
|
*
|
|
* Initializes the query plan: open files, allocate storage
|
|
* and start up the rule manager
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
static void
|
|
InitPlan(QueryDesc *queryDesc, bool explainOnly)
|
|
{
|
|
CmdType operation = queryDesc->operation;
|
|
Query *parseTree = queryDesc->parsetree;
|
|
Plan *plan = queryDesc->plantree;
|
|
EState *estate = queryDesc->estate;
|
|
PlanState *planstate;
|
|
List *rangeTable;
|
|
Relation intoRelationDesc;
|
|
bool do_select_into;
|
|
TupleDesc tupType;
|
|
|
|
/*
|
|
* Do permissions checks. It's sufficient to examine the query's top
|
|
* rangetable here --- subplan RTEs will be checked during
|
|
* ExecInitSubPlan().
|
|
*/
|
|
ExecCheckRTPerms(parseTree->rtable);
|
|
|
|
/*
|
|
* get information from query descriptor
|
|
*/
|
|
rangeTable = parseTree->rtable;
|
|
|
|
/*
|
|
* initialize the node's execution state
|
|
*/
|
|
estate->es_range_table = rangeTable;
|
|
|
|
/*
|
|
* if there is a result relation, initialize result relation stuff
|
|
*/
|
|
if (parseTree->resultRelation != 0 && operation != CMD_SELECT)
|
|
{
|
|
List *resultRelations = parseTree->resultRelations;
|
|
int numResultRelations;
|
|
ResultRelInfo *resultRelInfos;
|
|
|
|
if (resultRelations != NIL)
|
|
{
|
|
/*
|
|
* Multiple result relations (due to inheritance)
|
|
* parseTree->resultRelations identifies them all
|
|
*/
|
|
ResultRelInfo *resultRelInfo;
|
|
ListCell *l;
|
|
|
|
numResultRelations = list_length(resultRelations);
|
|
resultRelInfos = (ResultRelInfo *)
|
|
palloc(numResultRelations * sizeof(ResultRelInfo));
|
|
resultRelInfo = resultRelInfos;
|
|
foreach(l, resultRelations)
|
|
{
|
|
initResultRelInfo(resultRelInfo,
|
|
lfirst_int(l),
|
|
rangeTable,
|
|
operation,
|
|
estate->es_instrument);
|
|
resultRelInfo++;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Single result relation identified by
|
|
* parseTree->resultRelation
|
|
*/
|
|
numResultRelations = 1;
|
|
resultRelInfos = (ResultRelInfo *) palloc(sizeof(ResultRelInfo));
|
|
initResultRelInfo(resultRelInfos,
|
|
parseTree->resultRelation,
|
|
rangeTable,
|
|
operation,
|
|
estate->es_instrument);
|
|
}
|
|
|
|
estate->es_result_relations = resultRelInfos;
|
|
estate->es_num_result_relations = numResultRelations;
|
|
/* Initialize to first or only result rel */
|
|
estate->es_result_relation_info = resultRelInfos;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* if no result relation, then set state appropriately
|
|
*/
|
|
estate->es_result_relations = NULL;
|
|
estate->es_num_result_relations = 0;
|
|
estate->es_result_relation_info = NULL;
|
|
}
|
|
|
|
/*
|
|
* Detect whether we're doing SELECT INTO. If so, set the es_into_oids
|
|
* flag appropriately so that the plan tree will be initialized with
|
|
* the correct tuple descriptors.
|
|
*/
|
|
do_select_into = false;
|
|
|
|
if (operation == CMD_SELECT && parseTree->into != NULL)
|
|
{
|
|
do_select_into = true;
|
|
estate->es_select_into = true;
|
|
estate->es_into_oids = parseTree->intoHasOids;
|
|
}
|
|
|
|
/*
|
|
* Have to lock relations selected FOR UPDATE/FOR SHARE
|
|
*/
|
|
estate->es_rowMark = NIL;
|
|
estate->es_forUpdate = parseTree->forUpdate;
|
|
if (parseTree->rowMarks != NIL)
|
|
{
|
|
ListCell *l;
|
|
|
|
foreach(l, parseTree->rowMarks)
|
|
{
|
|
Index rti = lfirst_int(l);
|
|
Oid relid = getrelid(rti, rangeTable);
|
|
Relation relation;
|
|
execRowMark *erm;
|
|
|
|
relation = heap_open(relid, RowShareLock);
|
|
erm = (execRowMark *) palloc(sizeof(execRowMark));
|
|
erm->relation = relation;
|
|
erm->rti = rti;
|
|
snprintf(erm->resname, sizeof(erm->resname), "ctid%u", rti);
|
|
estate->es_rowMark = lappend(estate->es_rowMark, erm);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* initialize the executor "tuple" table. We need slots for all the
|
|
* plan nodes, plus possibly output slots for the junkfilter(s). At
|
|
* this point we aren't sure if we need junkfilters, so just add slots
|
|
* for them unconditionally.
|
|
*/
|
|
{
|
|
int nSlots = ExecCountSlotsNode(plan);
|
|
|
|
if (parseTree->resultRelations != NIL)
|
|
nSlots += list_length(parseTree->resultRelations);
|
|
else
|
|
nSlots += 1;
|
|
estate->es_tupleTable = ExecCreateTupleTable(nSlots);
|
|
}
|
|
|
|
/* mark EvalPlanQual not active */
|
|
estate->es_topPlan = plan;
|
|
estate->es_evalPlanQual = NULL;
|
|
estate->es_evTupleNull = NULL;
|
|
estate->es_evTuple = 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.
|
|
*/
|
|
planstate = ExecInitNode(plan, estate);
|
|
|
|
/*
|
|
* Get the tuple descriptor describing the type of tuples to return.
|
|
* (this is especially important if we are creating a relation with
|
|
* "SELECT INTO")
|
|
*/
|
|
tupType = ExecGetResultType(planstate);
|
|
|
|
/*
|
|
* Initialize the junk filter if needed. SELECT and INSERT queries
|
|
* need a filter if there are any junk attrs in the tlist. INSERT and
|
|
* SELECT INTO also need a filter if the plan may return raw disk
|
|
* tuples (else heap_insert will be scribbling on the source
|
|
* relation!). UPDATE and DELETE always need a filter, since there's
|
|
* always a junk 'ctid' attribute present --- no need to look first.
|
|
*/
|
|
{
|
|
bool junk_filter_needed = false;
|
|
ListCell *tlist;
|
|
|
|
switch (operation)
|
|
{
|
|
case CMD_SELECT:
|
|
case CMD_INSERT:
|
|
foreach(tlist, plan->targetlist)
|
|
{
|
|
TargetEntry *tle = (TargetEntry *) lfirst(tlist);
|
|
|
|
if (tle->resjunk)
|
|
{
|
|
junk_filter_needed = true;
|
|
break;
|
|
}
|
|
}
|
|
if (!junk_filter_needed &&
|
|
(operation == CMD_INSERT || do_select_into) &&
|
|
ExecMayReturnRawTuples(planstate))
|
|
junk_filter_needed = true;
|
|
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)
|
|
{
|
|
PlanState **appendplans;
|
|
int as_nplans;
|
|
ResultRelInfo *resultRelInfo;
|
|
int i;
|
|
|
|
/* Top plan had better be an Append here. */
|
|
Assert(IsA(plan, Append));
|
|
Assert(((Append *) plan)->isTarget);
|
|
Assert(IsA(planstate, AppendState));
|
|
appendplans = ((AppendState *) planstate)->appendplans;
|
|
as_nplans = ((AppendState *) planstate)->as_nplans;
|
|
Assert(as_nplans == estate->es_num_result_relations);
|
|
resultRelInfo = estate->es_result_relations;
|
|
for (i = 0; i < as_nplans; i++)
|
|
{
|
|
PlanState *subplan = appendplans[i];
|
|
JunkFilter *j;
|
|
|
|
j = ExecInitJunkFilter(subplan->plan->targetlist,
|
|
resultRelInfo->ri_RelationDesc->rd_att->tdhasoid,
|
|
ExecAllocTableSlot(estate->es_tupleTable));
|
|
resultRelInfo->ri_junkFilter = j;
|
|
resultRelInfo++;
|
|
}
|
|
|
|
/*
|
|
* 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(planstate->plan->targetlist,
|
|
tupType->tdhasoid,
|
|
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;
|
|
}
|
|
|
|
/*
|
|
* If doing SELECT INTO, initialize the "into" relation. We must wait
|
|
* till now so we have the "clean" result tuple type to create the new
|
|
* table from.
|
|
*
|
|
* If EXPLAIN, skip creating the "into" relation.
|
|
*/
|
|
intoRelationDesc = NULL;
|
|
|
|
if (do_select_into && !explainOnly)
|
|
{
|
|
char *intoName;
|
|
Oid namespaceId;
|
|
AclResult aclresult;
|
|
Oid intoRelationId;
|
|
TupleDesc tupdesc;
|
|
|
|
/*
|
|
* find namespace to create in, check permissions
|
|
*/
|
|
intoName = parseTree->into->relname;
|
|
namespaceId = RangeVarGetCreationNamespace(parseTree->into);
|
|
|
|
aclresult = pg_namespace_aclcheck(namespaceId, GetUserId(),
|
|
ACL_CREATE);
|
|
if (aclresult != ACLCHECK_OK)
|
|
aclcheck_error(aclresult, ACL_KIND_NAMESPACE,
|
|
get_namespace_name(namespaceId));
|
|
|
|
/*
|
|
* have to copy tupType to get rid of constraints
|
|
*/
|
|
tupdesc = CreateTupleDescCopy(tupType);
|
|
|
|
intoRelationId = heap_create_with_catalog(intoName,
|
|
namespaceId,
|
|
InvalidOid,
|
|
InvalidOid,
|
|
tupdesc,
|
|
RELKIND_RELATION,
|
|
false,
|
|
true,
|
|
0,
|
|
ONCOMMIT_NOOP,
|
|
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(intoRelationId, true);
|
|
|
|
/*
|
|
* And open the constructed table for writing.
|
|
*/
|
|
intoRelationDesc = heap_open(intoRelationId, AccessExclusiveLock);
|
|
}
|
|
|
|
estate->es_into_relation_descriptor = intoRelationDesc;
|
|
|
|
queryDesc->tupDesc = tupType;
|
|
queryDesc->planstate = planstate;
|
|
}
|
|
|
|
/*
|
|
* Initialize ResultRelInfo data for one result relation
|
|
*/
|
|
static void
|
|
initResultRelInfo(ResultRelInfo *resultRelInfo,
|
|
Index resultRelationIndex,
|
|
List *rangeTable,
|
|
CmdType operation,
|
|
bool doInstrument)
|
|
{
|
|
Oid resultRelationOid;
|
|
Relation resultRelationDesc;
|
|
|
|
resultRelationOid = getrelid(resultRelationIndex, rangeTable);
|
|
resultRelationDesc = heap_open(resultRelationOid, RowExclusiveLock);
|
|
|
|
switch (resultRelationDesc->rd_rel->relkind)
|
|
{
|
|
case RELKIND_SEQUENCE:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
|
|
errmsg("cannot change sequence \"%s\"",
|
|
RelationGetRelationName(resultRelationDesc))));
|
|
break;
|
|
case RELKIND_TOASTVALUE:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
|
|
errmsg("cannot change TOAST relation \"%s\"",
|
|
RelationGetRelationName(resultRelationDesc))));
|
|
break;
|
|
case RELKIND_VIEW:
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
|
|
errmsg("cannot change view \"%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;
|
|
/* make a copy so as not to depend on relcache info not changing... */
|
|
resultRelInfo->ri_TrigDesc = CopyTriggerDesc(resultRelationDesc->trigdesc);
|
|
if (resultRelInfo->ri_TrigDesc)
|
|
{
|
|
int n = resultRelInfo->ri_TrigDesc->numtriggers;
|
|
|
|
resultRelInfo->ri_TrigFunctions = (FmgrInfo *)
|
|
palloc0(n * sizeof(FmgrInfo));
|
|
if (doInstrument)
|
|
resultRelInfo->ri_TrigInstrument = InstrAlloc(n);
|
|
else
|
|
resultRelInfo->ri_TrigInstrument = NULL;
|
|
}
|
|
else
|
|
{
|
|
resultRelInfo->ri_TrigFunctions = NULL;
|
|
resultRelInfo->ri_TrigInstrument = 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);
|
|
}
|
|
|
|
/*
|
|
* ExecContextForcesOids
|
|
*
|
|
* This is pretty grotty: when doing INSERT, UPDATE, or SELECT INTO,
|
|
* we need to ensure that result tuples have space for an OID iff they are
|
|
* going to be stored into a relation that has OIDs. In other contexts
|
|
* we are free to choose whether to leave space for OIDs in result tuples
|
|
* (we generally don't want to, but we do if a physical-tlist optimization
|
|
* is possible). This routine checks the plan context and returns TRUE if the
|
|
* choice is forced, FALSE if the choice is not forced. In the TRUE case,
|
|
* *hasoids is set to the required value.
|
|
*
|
|
* One reason this is ugly is that all plan nodes in the plan tree will emit
|
|
* tuples with space for an OID, though we really only need the topmost node
|
|
* to do so. However, node types like Sort don't project new tuples but just
|
|
* return their inputs, and in those cases the requirement propagates down
|
|
* to the input node. Eventually we might make this code smart enough to
|
|
* recognize how far down the requirement really goes, but for now we just
|
|
* make all plan nodes do the same thing if the top level forces the choice.
|
|
*
|
|
* We assume that estate->es_result_relation_info is already set up to
|
|
* describe the target relation. Note that in an UPDATE that spans an
|
|
* inheritance tree, some of the target relations may have OIDs and some not.
|
|
* We have to make the decisions on a per-relation basis as we initialize
|
|
* each of the child plans of the topmost Append plan.
|
|
*
|
|
* SELECT INTO is even uglier, because we don't have the INTO relation's
|
|
* descriptor available when this code runs; we have to look aside at a
|
|
* flag set by InitPlan().
|
|
*/
|
|
bool
|
|
ExecContextForcesOids(PlanState *planstate, bool *hasoids)
|
|
{
|
|
if (planstate->state->es_select_into)
|
|
{
|
|
*hasoids = planstate->state->es_into_oids;
|
|
return true;
|
|
}
|
|
else
|
|
{
|
|
ResultRelInfo *ri = planstate->state->es_result_relation_info;
|
|
|
|
if (ri != NULL)
|
|
{
|
|
Relation rel = ri->ri_RelationDesc;
|
|
|
|
if (rel != NULL)
|
|
{
|
|
*hasoids = rel->rd_rel->relhasoids;
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecEndPlan
|
|
*
|
|
* Cleans up the query plan -- closes files and frees up storage
|
|
*
|
|
* NOTE: we are no longer very worried about freeing storage per se
|
|
* in this code; FreeExecutorState should be guaranteed to release all
|
|
* memory that needs to be released. What we are worried about doing
|
|
* is closing relations and dropping buffer pins. Thus, for example,
|
|
* tuple tables must be cleared or dropped to ensure pins are released.
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
void
|
|
ExecEndPlan(PlanState *planstate, EState *estate)
|
|
{
|
|
ResultRelInfo *resultRelInfo;
|
|
int i;
|
|
ListCell *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(planstate);
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
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);
|
|
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);
|
|
|
|
/*
|
|
* close any relations selected FOR UPDATE/FOR SHARE, 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 SELECT 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,
|
|
PlanState *planstate,
|
|
CmdType operation,
|
|
long numberTuples,
|
|
ScanDirection direction,
|
|
DestReceiver *dest)
|
|
{
|
|
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;
|
|
|
|
/*
|
|
* Process BEFORE EACH STATEMENT triggers
|
|
*/
|
|
switch (operation)
|
|
{
|
|
case CMD_UPDATE:
|
|
ExecBSUpdateTriggers(estate, estate->es_result_relation_info);
|
|
break;
|
|
case CMD_DELETE:
|
|
ExecBSDeleteTriggers(estate, estate->es_result_relation_info);
|
|
break;
|
|
case CMD_INSERT:
|
|
ExecBSInsertTriggers(estate, estate->es_result_relation_info);
|
|
break;
|
|
default:
|
|
/* do nothing */
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* 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(planstate);
|
|
}
|
|
else
|
|
slot = ExecProcNode(planstate);
|
|
|
|
/*
|
|
* 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) != NULL)
|
|
{
|
|
Datum datum;
|
|
bool isNull;
|
|
|
|
/*
|
|
* extract the 'ctid' junk attribute.
|
|
*/
|
|
if (operation == CMD_UPDATE || operation == CMD_DELETE)
|
|
{
|
|
if (!ExecGetJunkAttribute(junkfilter,
|
|
slot,
|
|
"ctid",
|
|
&datum,
|
|
&isNull))
|
|
elog(ERROR, "could not find junk ctid column");
|
|
|
|
/* shouldn't ever get a null result... */
|
|
if (isNull)
|
|
elog(ERROR, "ctid is NULL");
|
|
|
|
tupleid = (ItemPointer) DatumGetPointer(datum);
|
|
tuple_ctid = *tupleid; /* make sure we don't free the
|
|
* ctid!! */
|
|
tupleid = &tuple_ctid;
|
|
}
|
|
/*
|
|
* Process any FOR UPDATE or FOR SHARE locking requested.
|
|
*/
|
|
else if (estate->es_rowMark != NIL)
|
|
{
|
|
ListCell *l;
|
|
|
|
lmark: ;
|
|
foreach(l, estate->es_rowMark)
|
|
{
|
|
execRowMark *erm = lfirst(l);
|
|
Buffer buffer;
|
|
HeapTupleData tuple;
|
|
TupleTableSlot *newSlot;
|
|
LockTupleMode lockmode;
|
|
HTSU_Result test;
|
|
|
|
if (!ExecGetJunkAttribute(junkfilter,
|
|
slot,
|
|
erm->resname,
|
|
&datum,
|
|
&isNull))
|
|
elog(ERROR, "could not find junk \"%s\" column",
|
|
erm->resname);
|
|
|
|
/* shouldn't ever get a null result... */
|
|
if (isNull)
|
|
elog(ERROR, "\"%s\" is NULL", erm->resname);
|
|
|
|
if (estate->es_forUpdate)
|
|
lockmode = LockTupleExclusive;
|
|
else
|
|
lockmode = LockTupleShared;
|
|
|
|
tuple.t_self = *((ItemPointer) DatumGetPointer(datum));
|
|
test = heap_lock_tuple(erm->relation, &tuple, &buffer,
|
|
estate->es_snapshot->curcid,
|
|
lockmode);
|
|
ReleaseBuffer(buffer);
|
|
switch (test)
|
|
{
|
|
case HeapTupleSelfUpdated:
|
|
/* treat it as deleted; do not process */
|
|
goto lnext;
|
|
|
|
case HeapTupleMayBeUpdated:
|
|
break;
|
|
|
|
case HeapTupleUpdated:
|
|
if (IsXactIsoLevelSerializable)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
|
|
errmsg("could not 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, "unrecognized heap_lock_tuple status: %u",
|
|
test);
|
|
return (NULL);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Finally create a new "clean" tuple with all junk attributes
|
|
* removed
|
|
*/
|
|
slot = ExecFilterJunk(junkfilter, slot);
|
|
}
|
|
|
|
/*
|
|
* 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:
|
|
ExecSelect(slot, /* slot containing tuple */
|
|
dest, /* destination's tuple-receiver obj */
|
|
estate);
|
|
result = slot;
|
|
break;
|
|
|
|
case CMD_INSERT:
|
|
ExecInsert(slot, tupleid, estate);
|
|
result = NULL;
|
|
break;
|
|
|
|
case CMD_DELETE:
|
|
ExecDelete(slot, tupleid, estate);
|
|
result = NULL;
|
|
break;
|
|
|
|
case CMD_UPDATE:
|
|
ExecUpdate(slot, tupleid, estate);
|
|
result = NULL;
|
|
break;
|
|
|
|
default:
|
|
elog(ERROR, "unrecognized operation code: %d",
|
|
(int) operation);
|
|
result = NULL;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* check our tuple count.. if we've processed the proper number
|
|
* then quit, else loop again and process more tuples. Zero
|
|
* numberTuples means no limit.
|
|
*/
|
|
current_tuple_count++;
|
|
if (numberTuples && numberTuples == current_tuple_count)
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Process AFTER EACH STATEMENT triggers
|
|
*/
|
|
switch (operation)
|
|
{
|
|
case CMD_UPDATE:
|
|
ExecASUpdateTriggers(estate, estate->es_result_relation_info);
|
|
break;
|
|
case CMD_DELETE:
|
|
ExecASDeleteTriggers(estate, estate->es_result_relation_info);
|
|
break;
|
|
case CMD_INSERT:
|
|
ExecASInsertTriggers(estate, estate->es_result_relation_info);
|
|
break;
|
|
default:
|
|
/* do nothing */
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* here, result is either a slot containing a tuple in the case of a
|
|
* SELECT or NULL otherwise.
|
|
*/
|
|
return result;
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecSelect
|
|
*
|
|
* SELECTs are easy.. we just pass the tuple to the appropriate
|
|
* print function. The only complexity is when we do a
|
|
* "SELECT 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
|
|
ExecSelect(TupleTableSlot *slot,
|
|
DestReceiver *dest,
|
|
EState *estate)
|
|
{
|
|
/*
|
|
* insert the tuple into the "into relation"
|
|
*
|
|
* XXX this probably ought to be replaced by a separate destination
|
|
*/
|
|
if (estate->es_into_relation_descriptor != NULL)
|
|
{
|
|
HeapTuple tuple;
|
|
|
|
tuple = ExecCopySlotTuple(slot);
|
|
heap_insert(estate->es_into_relation_descriptor, tuple,
|
|
estate->es_snapshot->curcid);
|
|
/* we know there are no indexes to update */
|
|
heap_freetuple(tuple);
|
|
IncrAppended();
|
|
}
|
|
|
|
/*
|
|
* send the tuple to the destination
|
|
*/
|
|
(*dest->receiveSlot) (slot, dest);
|
|
IncrRetrieved();
|
|
(estate->es_processed)++;
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecInsert
|
|
*
|
|
* INSERTs are trickier.. we have to insert the tuple into
|
|
* the base relation and insert appropriate tuples into the
|
|
* index relations.
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
static void
|
|
ExecInsert(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, making sure
|
|
* we have a writable copy
|
|
*/
|
|
tuple = ExecMaterializeSlot(slot);
|
|
|
|
/*
|
|
* 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(resultRelInfo, slot, estate);
|
|
|
|
/*
|
|
* insert the tuple
|
|
*/
|
|
newId = heap_insert(resultRelationDesc, tuple,
|
|
estate->es_snapshot->curcid);
|
|
|
|
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 */
|
|
ExecARInsertTriggers(estate, resultRelInfo, tuple);
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecDelete
|
|
*
|
|
* DELETE is like UPDATE, we delete the tuple and its
|
|
* index tuples.
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
static void
|
|
ExecDelete(TupleTableSlot *slot,
|
|
ItemPointer tupleid,
|
|
EState *estate)
|
|
{
|
|
ResultRelInfo *resultRelInfo;
|
|
Relation resultRelationDesc;
|
|
ItemPointerData ctid;
|
|
HTSU_Result 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,
|
|
estate->es_snapshot->curcid);
|
|
|
|
if (!dodelete) /* "do nothing" */
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* delete the tuple
|
|
*
|
|
* Note: if es_crosscheck_snapshot isn't InvalidSnapshot, we check that
|
|
* the row to be deleted is visible to that snapshot, and throw a can't-
|
|
* serialize error if not. This is a special-case behavior needed for
|
|
* referential integrity updates in serializable transactions.
|
|
*/
|
|
ldelete:;
|
|
result = heap_delete(resultRelationDesc, tupleid,
|
|
&ctid,
|
|
estate->es_snapshot->curcid,
|
|
estate->es_crosscheck_snapshot,
|
|
true /* wait for commit */ );
|
|
switch (result)
|
|
{
|
|
case HeapTupleSelfUpdated:
|
|
/* already deleted by self; nothing to do */
|
|
return;
|
|
|
|
case HeapTupleMayBeUpdated:
|
|
break;
|
|
|
|
case HeapTupleUpdated:
|
|
if (IsXactIsoLevelSerializable)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
|
|
errmsg("could not serialize access due to concurrent update")));
|
|
else if (!(ItemPointerEquals(tupleid, &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, "unrecognized heap_delete status: %u", 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 */
|
|
ExecARDeleteTriggers(estate, resultRelInfo, tupleid);
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecUpdate
|
|
*
|
|
* note: we can't run UPDATE queries with transactions
|
|
* off because UPDATEs are actually INSERTs and our
|
|
* scan will mistakenly loop forever, updating the tuple
|
|
* it just inserted.. This should be fixed but until it
|
|
* is, we don't want to get stuck in an infinite loop
|
|
* which corrupts your database..
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
static void
|
|
ExecUpdate(TupleTableSlot *slot,
|
|
ItemPointer tupleid,
|
|
EState *estate)
|
|
{
|
|
HeapTuple tuple;
|
|
ResultRelInfo *resultRelInfo;
|
|
Relation resultRelationDesc;
|
|
ItemPointerData ctid;
|
|
HTSU_Result result;
|
|
int numIndices;
|
|
|
|
/*
|
|
* abort the operation if not running transactions
|
|
*/
|
|
if (IsBootstrapProcessingMode())
|
|
elog(ERROR, "cannot UPDATE during bootstrap");
|
|
|
|
/*
|
|
* get the heap tuple out of the tuple table slot, making sure
|
|
* we have a writable copy
|
|
*/
|
|
tuple = ExecMaterializeSlot(slot);
|
|
|
|
/*
|
|
* 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,
|
|
estate->es_snapshot->curcid);
|
|
|
|
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 heap_lock_tuple to lock the correct tuple,
|
|
* so there's no need to do them again.)
|
|
*/
|
|
lreplace:;
|
|
if (resultRelationDesc->rd_att->constr)
|
|
ExecConstraints(resultRelInfo, slot, estate);
|
|
|
|
/*
|
|
* replace the heap tuple
|
|
*
|
|
* Note: if es_crosscheck_snapshot isn't InvalidSnapshot, we check that
|
|
* the row to be updated is visible to that snapshot, and throw a can't-
|
|
* serialize error if not. This is a special-case behavior needed for
|
|
* referential integrity updates in serializable transactions.
|
|
*/
|
|
result = heap_update(resultRelationDesc, tupleid, tuple,
|
|
&ctid,
|
|
estate->es_snapshot->curcid,
|
|
estate->es_crosscheck_snapshot,
|
|
true /* wait for commit */ );
|
|
switch (result)
|
|
{
|
|
case HeapTupleSelfUpdated:
|
|
/* already deleted by self; nothing to do */
|
|
return;
|
|
|
|
case HeapTupleMayBeUpdated:
|
|
break;
|
|
|
|
case HeapTupleUpdated:
|
|
if (IsXactIsoLevelSerializable)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
|
|
errmsg("could not serialize access due to concurrent update")));
|
|
else if (!(ItemPointerEquals(tupleid, &ctid)))
|
|
{
|
|
TupleTableSlot *epqslot = EvalPlanQual(estate,
|
|
resultRelInfo->ri_RangeTableIndex, &ctid);
|
|
|
|
if (!TupIsNull(epqslot))
|
|
{
|
|
*tupleid = ctid;
|
|
slot = ExecFilterJunk(estate->es_junkFilter, epqslot);
|
|
tuple = ExecMaterializeSlot(slot);
|
|
goto lreplace;
|
|
}
|
|
}
|
|
/* tuple already deleted; nothing to do */
|
|
return;
|
|
|
|
default:
|
|
elog(ERROR, "unrecognized heap_update status: %u", 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 UPDATEs 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 inserting 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, false);
|
|
|
|
/* AFTER ROW UPDATE Triggers */
|
|
ExecARUpdateTriggers(estate, resultRelInfo, tupleid, tuple);
|
|
}
|
|
|
|
static const 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++)
|
|
{
|
|
/* ExecQual wants implicit-AND form */
|
|
qual = make_ands_implicit(stringToNode(check[i].ccbin));
|
|
resultRelInfo->ri_ConstraintExprs[i] = (List *)
|
|
ExecPrepareExpr((Expr *) qual, estate);
|
|
}
|
|
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 NULL;
|
|
}
|
|
|
|
void
|
|
ExecConstraints(ResultRelInfo *resultRelInfo,
|
|
TupleTableSlot *slot, EState *estate)
|
|
{
|
|
Relation rel = resultRelInfo->ri_RelationDesc;
|
|
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 &&
|
|
slot_attisnull(slot, attrChk))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_NOT_NULL_VIOLATION),
|
|
errmsg("null value in column \"%s\" violates not-null constraint",
|
|
NameStr(rel->rd_att->attrs[attrChk - 1]->attname))));
|
|
}
|
|
}
|
|
|
|
if (constr->num_check > 0)
|
|
{
|
|
const char *failed;
|
|
|
|
if ((failed = ExecRelCheck(resultRelInfo, slot, estate)) != NULL)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_CHECK_VIOLATION),
|
|
errmsg("new row for relation \"%s\" violates check constraint \"%s\"",
|
|
RelationGetRelationName(rel), 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;
|
|
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
|
|
{
|
|
ListCell *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, "could not find RowMark for RT index %u", rti);
|
|
}
|
|
|
|
/*
|
|
* fetch tid tuple
|
|
*
|
|
* Loop here to deal with updated or busy tuples
|
|
*/
|
|
tuple.t_self = *tid;
|
|
for (;;)
|
|
{
|
|
Buffer buffer;
|
|
|
|
if (heap_fetch(relation, SnapshotDirty, &tuple, &buffer, false, NULL))
|
|
{
|
|
TransactionId xwait = SnapshotDirty->xmax;
|
|
|
|
/* xmin should not be dirty... */
|
|
if (TransactionIdIsValid(SnapshotDirty->xmin))
|
|
elog(ERROR, "t_xmin is uncommitted in tuple to be updated");
|
|
|
|
/*
|
|
* 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 = estate->es_evalPlanQual;
|
|
endNode = true;
|
|
|
|
if (epq != NULL && epq->rti == 0)
|
|
{
|
|
/* Top PQ stack entry is idle, so re-use it */
|
|
Assert(!(estate->es_useEvalPlan) && epq->next == 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;
|
|
|
|
/* stop execution */
|
|
EvalPlanQualStop(epq);
|
|
/* pop previous PlanQual from the stack */
|
|
oldepq = epq->next;
|
|
Assert(oldepq && oldepq->rti != 0);
|
|
/* push current PQ to freePQ stack */
|
|
oldepq->free = epq;
|
|
epq = oldepq;
|
|
estate->es_evalPlanQual = 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 *) palloc0(sizeof(evalPlanQual));
|
|
newepq->free = NULL;
|
|
newepq->estate = NULL;
|
|
newepq->planstate = NULL;
|
|
}
|
|
else
|
|
{
|
|
/* recycle previously used PlanQual */
|
|
Assert(newepq->estate == NULL);
|
|
epq->free = NULL;
|
|
}
|
|
/* push current PQ to the stack */
|
|
newepq->next = epq;
|
|
epq = newepq;
|
|
estate->es_evalPlanQual = epq;
|
|
epq->rti = rti;
|
|
endNode = false;
|
|
}
|
|
|
|
Assert(epq->rti == rti);
|
|
|
|
/*
|
|
* 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.
|
|
*
|
|
* Note that the stack of free evalPlanQual nodes is quite useless at the
|
|
* moment, since it only saves us from pallocing/releasing the
|
|
* evalPlanQual nodes themselves. But it will be useful once we
|
|
* implement ReScan instead of end/restart for re-using PlanQual
|
|
* nodes.
|
|
*/
|
|
if (endNode)
|
|
{
|
|
/* stop execution */
|
|
EvalPlanQualStop(epq);
|
|
}
|
|
|
|
/*
|
|
* Initialize new recheck query.
|
|
*
|
|
* Note: if we were re-using PlanQual plans via ExecReScan, we'd need to
|
|
* instead copy down changeable state from the top plan (including
|
|
* es_result_relation_info, es_junkFilter) and reset locally
|
|
* changeable state in the epq (including es_param_exec_vals,
|
|
* es_evTupleNull).
|
|
*/
|
|
EvalPlanQualStart(epq, estate, epq->next);
|
|
|
|
/*
|
|
* free old RTE' tuple, if any, and store target tuple where
|
|
* relation's scan node will see it
|
|
*/
|
|
epqstate = epq->estate;
|
|
if (epqstate->es_evTuple[rti - 1] != NULL)
|
|
heap_freetuple(epqstate->es_evTuple[rti - 1]);
|
|
epqstate->es_evTuple[rti - 1] = copyTuple;
|
|
|
|
return EvalPlanQualNext(estate);
|
|
}
|
|
|
|
static TupleTableSlot *
|
|
EvalPlanQualNext(EState *estate)
|
|
{
|
|
evalPlanQual *epq = estate->es_evalPlanQual;
|
|
MemoryContext oldcontext;
|
|
TupleTableSlot *slot;
|
|
|
|
Assert(epq->rti != 0);
|
|
|
|
lpqnext:;
|
|
oldcontext = MemoryContextSwitchTo(epq->estate->es_query_cxt);
|
|
slot = ExecProcNode(epq->planstate);
|
|
MemoryContextSwitchTo(oldcontext);
|
|
|
|
/*
|
|
* No more tuples for this PQ. Continue previous one.
|
|
*/
|
|
if (TupIsNull(slot))
|
|
{
|
|
evalPlanQual *oldepq;
|
|
|
|
/* stop execution */
|
|
EvalPlanQualStop(epq);
|
|
/* pop old PQ from the stack */
|
|
oldepq = epq->next;
|
|
if (oldepq == NULL)
|
|
{
|
|
/* this is the first (oldest) PQ - mark as free */
|
|
epq->rti = 0;
|
|
estate->es_useEvalPlan = false;
|
|
/* and continue Query execution */
|
|
return (NULL);
|
|
}
|
|
Assert(oldepq->rti != 0);
|
|
/* push current PQ to freePQ stack */
|
|
oldepq->free = epq;
|
|
epq = oldepq;
|
|
estate->es_evalPlanQual = epq;
|
|
goto lpqnext;
|
|
}
|
|
|
|
return (slot);
|
|
}
|
|
|
|
static void
|
|
EndEvalPlanQual(EState *estate)
|
|
{
|
|
evalPlanQual *epq = estate->es_evalPlanQual;
|
|
|
|
if (epq->rti == 0) /* plans already shutdowned */
|
|
{
|
|
Assert(epq->next == NULL);
|
|
return;
|
|
}
|
|
|
|
for (;;)
|
|
{
|
|
evalPlanQual *oldepq;
|
|
|
|
/* stop execution */
|
|
EvalPlanQualStop(epq);
|
|
/* pop old PQ from the stack */
|
|
oldepq = epq->next;
|
|
if (oldepq == NULL)
|
|
{
|
|
/* this is the first (oldest) PQ - mark as free */
|
|
epq->rti = 0;
|
|
estate->es_useEvalPlan = false;
|
|
break;
|
|
}
|
|
Assert(oldepq->rti != 0);
|
|
/* push current PQ to freePQ stack */
|
|
oldepq->free = epq;
|
|
epq = oldepq;
|
|
estate->es_evalPlanQual = epq;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Start execution of one level of PlanQual.
|
|
*
|
|
* This is a cut-down version of ExecutorStart(): we copy some state from
|
|
* the top-level estate rather than initializing it fresh.
|
|
*/
|
|
static void
|
|
EvalPlanQualStart(evalPlanQual *epq, EState *estate, evalPlanQual *priorepq)
|
|
{
|
|
EState *epqstate;
|
|
int rtsize;
|
|
MemoryContext oldcontext;
|
|
|
|
rtsize = list_length(estate->es_range_table);
|
|
|
|
epq->estate = epqstate = CreateExecutorState();
|
|
|
|
oldcontext = MemoryContextSwitchTo(epqstate->es_query_cxt);
|
|
|
|
/*
|
|
* The epqstates share the top query's copy of unchanging state such
|
|
* as the snapshot, rangetable, result-rel info, and external Param
|
|
* info. They need their own copies of local state, including a tuple
|
|
* table, es_param_exec_vals, etc.
|
|
*/
|
|
epqstate->es_direction = ForwardScanDirection;
|
|
epqstate->es_snapshot = estate->es_snapshot;
|
|
epqstate->es_crosscheck_snapshot = estate->es_crosscheck_snapshot;
|
|
epqstate->es_range_table = estate->es_range_table;
|
|
epqstate->es_result_relations = estate->es_result_relations;
|
|
epqstate->es_num_result_relations = estate->es_num_result_relations;
|
|
epqstate->es_result_relation_info = estate->es_result_relation_info;
|
|
epqstate->es_junkFilter = estate->es_junkFilter;
|
|
epqstate->es_into_relation_descriptor = estate->es_into_relation_descriptor;
|
|
epqstate->es_param_list_info = estate->es_param_list_info;
|
|
if (estate->es_topPlan->nParamExec > 0)
|
|
epqstate->es_param_exec_vals = (ParamExecData *)
|
|
palloc0(estate->es_topPlan->nParamExec * sizeof(ParamExecData));
|
|
epqstate->es_rowMark = estate->es_rowMark;
|
|
epqstate->es_forUpdate = estate->es_forUpdate;
|
|
epqstate->es_instrument = estate->es_instrument;
|
|
epqstate->es_select_into = estate->es_select_into;
|
|
epqstate->es_into_oids = estate->es_into_oids;
|
|
epqstate->es_topPlan = estate->es_topPlan;
|
|
|
|
/*
|
|
* 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 *) palloc0(rtsize * sizeof(bool));
|
|
if (priorepq == NULL)
|
|
/* first PQ stack entry */
|
|
epqstate->es_evTuple = (HeapTuple *)
|
|
palloc0(rtsize * sizeof(HeapTuple));
|
|
else
|
|
/* later stack entries share the same storage */
|
|
epqstate->es_evTuple = priorepq->estate->es_evTuple;
|
|
|
|
epqstate->es_tupleTable =
|
|
ExecCreateTupleTable(estate->es_tupleTable->size);
|
|
|
|
epq->planstate = ExecInitNode(estate->es_topPlan, epqstate);
|
|
|
|
MemoryContextSwitchTo(oldcontext);
|
|
}
|
|
|
|
/*
|
|
* End execution of one level of PlanQual.
|
|
*
|
|
* This is a cut-down version of ExecutorEnd(); basically we want to do most
|
|
* of the normal cleanup, but *not* close result relations (which we are
|
|
* just sharing from the outer query).
|
|
*/
|
|
static void
|
|
EvalPlanQualStop(evalPlanQual *epq)
|
|
{
|
|
EState *epqstate = epq->estate;
|
|
MemoryContext oldcontext;
|
|
|
|
oldcontext = MemoryContextSwitchTo(epqstate->es_query_cxt);
|
|
|
|
ExecEndNode(epq->planstate);
|
|
|
|
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;
|
|
}
|
|
|
|
MemoryContextSwitchTo(oldcontext);
|
|
|
|
FreeExecutorState(epqstate);
|
|
|
|
epq->estate = NULL;
|
|
epq->planstate = NULL;
|
|
}
|