*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/executor/execMain.c,v 1.261 2005/11/22 18:17:10 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/executor/execMain.c,v 1.262 2005/12/02 20:03:40 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#include "utils/memutils.h"
-typedef struct execRowMark
-{
- Relation relation;
- Index rti;
- char resname[32];
-} execRowMark;
-
typedef struct evalPlanQual
{
Index rti;
Index rti = lfirst_int(l);
Oid relid = getrelid(rti, rangeTable);
Relation relation;
- execRowMark *erm;
+ ExecRowMark *erm;
relation = heap_open(relid, RowShareLock);
- erm = (execRowMark *) palloc(sizeof(execRowMark));
+ erm = (ExecRowMark *) palloc(sizeof(ExecRowMark));
erm->relation = relation;
erm->rti = rti;
snprintf(erm->resname, sizeof(erm->resname), "ctid%u", rti);
*/
foreach(l, estate->es_rowMarks)
{
- execRowMark *erm = lfirst(l);
+ ExecRowMark *erm = lfirst(l);
heap_close(erm->relation, NoLock);
}
lmark: ;
foreach(l, estate->es_rowMarks)
{
- execRowMark *erm = lfirst(l);
+ ExecRowMark *erm = lfirst(l);
HeapTupleData tuple;
Buffer buffer;
ItemPointerData update_ctid;
relation = NULL;
foreach(l, estate->es_rowMarks)
{
- if (((execRowMark *) lfirst(l))->rti == rti)
+ if (((ExecRowMark *) lfirst(l))->rti == rti)
{
- relation = ((execRowMark *) lfirst(l))->relation;
+ relation = ((ExecRowMark *) lfirst(l))->relation;
break;
}
}
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/executor/execUtils.c,v 1.129 2005/11/23 20:27:57 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/executor/execUtils.c,v 1.130 2005/12/02 20:03:40 tgl Exp $
*
*-------------------------------------------------------------------------
*/
* ExecAssignResultType
* etc
*
+ * ExecOpenScanRelation Common code for scan node init routines.
+ * ExecCloseScanRelation
+ *
* ExecOpenIndices \
* ExecCloseIndices | referenced by InitPlan, EndPlan,
* ExecInsertIndexTuples / ExecInsert, ExecUpdate
#include "catalog/pg_index.h"
#include "executor/execdebug.h"
#include "miscadmin.h"
+#include "parser/parsetree.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
#include "utils/memutils.h"
/* ----------------------------------------------------------------
+ * Scan node support
+ * ----------------------------------------------------------------
+ */
+
+/* ----------------------------------------------------------------
+ * ExecOpenScanRelation
+ *
+ * Open the heap relation to be scanned by a base-level scan plan node.
+ * This should be called during the node's ExecInit routine.
+ *
+ * By default, this acquires AccessShareLock on the relation. However,
+ * if the relation was already locked by InitPlan, we don't need to acquire
+ * any additional lock. This saves trips to the shared lock manager.
+ * ----------------------------------------------------------------
+ */
+Relation
+ExecOpenScanRelation(EState *estate, Index scanrelid)
+{
+ RangeTblEntry *rtentry;
+ Oid reloid;
+ LOCKMODE lockmode;
+ ResultRelInfo *resultRelInfos;
+ int i;
+
+ /*
+ * First determine the lock type we need. Scan to see if target relation
+ * is either a result relation or a FOR UPDATE/FOR SHARE relation.
+ */
+ lockmode = AccessShareLock;
+ resultRelInfos = estate->es_result_relations;
+ for (i = 0; i < estate->es_num_result_relations; i++)
+ {
+ if (resultRelInfos[i].ri_RangeTableIndex == scanrelid)
+ {
+ lockmode = NoLock;
+ break;
+ }
+ }
+
+ if (lockmode == AccessShareLock)
+ {
+ ListCell *l;
+
+ foreach(l, estate->es_rowMarks)
+ {
+ ExecRowMark *erm = lfirst(l);
+
+ if (erm->rti == scanrelid)
+ {
+ lockmode = NoLock;
+ break;
+ }
+ }
+ }
+
+ /* OK, open the relation and acquire lock as needed */
+ rtentry = rt_fetch(scanrelid, estate->es_range_table);
+ reloid = rtentry->relid;
+
+ return heap_open(reloid, lockmode);
+}
+
+/* ----------------------------------------------------------------
+ * ExecCloseScanRelation
+ *
+ * Close the heap relation scanned by a base-level scan plan node.
+ * This should be called during the node's ExecEnd routine.
+ *
+ * Currently, we do not release the lock acquired by ExecOpenScanRelation.
+ * This lock should be held till end of transaction. (There is a faction
+ * that considers this too much locking, however.)
+ *
+ * If we did want to release the lock, we'd have to repeat the logic in
+ * ExecOpenScanRelation in order to figure out what to release.
+ * ----------------------------------------------------------------
+ */
+void
+ExecCloseScanRelation(Relation scanrel)
+{
+ heap_close(scanrel, NoLock);
+}
+
+
+/* ----------------------------------------------------------------
* ExecInsertIndexTuples support
* ----------------------------------------------------------------
*/
*
* If the index AM is not safe for concurrent updates, obtain an
* exclusive lock on the index to lock out other updaters as well as
- * readers (index_beginscan places AccessShareLock).
+ * readers (index_beginscan places AccessShareLock on the index).
*
* If there are multiple not-concurrent-safe indexes, all backends
* must lock the indexes in the same order or we will get deadlocks
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/executor/nodeBitmapHeapscan.c,v 1.7 2005/12/02 01:29:55 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/executor/nodeBitmapHeapscan.c,v 1.8 2005/12/02 20:03:40 tgl Exp $
*
*-------------------------------------------------------------------------
*/
/*
* Ignore any claimed entries past what we think is the end of the
- * relation. (This is probably not necessary given that we got
- * AccessShareLock before performing any of the indexscans, but
- * let's be safe.)
+ * relation. (This is probably not necessary given that we got at
+ * least AccessShareLock on the table before performing any of the
+ * indexscans, but let's be safe.)
*/
if (tbmres->blockno >= scan->rs_nblocks)
{
/*
* close the heap relation.
- *
- * Currently, we do not release the AccessShareLock acquired by
- * ExecInitBitmapHeapScan. This lock should be held till end of
- * transaction. (There is a faction that considers this too much locking,
- * however.)
*/
- heap_close(relation, NoLock);
+ ExecCloseScanRelation(relation);
}
/* ----------------------------------------------------------------
ExecInitBitmapHeapScan(BitmapHeapScan *node, EState *estate)
{
BitmapHeapScanState *scanstate;
- RangeTblEntry *rtentry;
- Index relid;
- Oid reloid;
Relation currentRelation;
/*
CXT1_printf("ExecInitBitmapHeapScan: context is %d\n", CurrentMemoryContext);
/*
- * open the base relation and acquire AccessShareLock on it.
+ * open the base relation and acquire appropriate lock on it.
*/
- relid = node->scan.scanrelid;
- rtentry = rt_fetch(relid, estate->es_range_table);
- reloid = rtentry->relid;
-
- currentRelation = heap_open(reloid, AccessShareLock);
+ currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid);
scanstate->ss.ss_currentRelation = currentRelation;
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/executor/nodeBitmapIndexscan.c,v 1.12 2005/11/25 19:47:49 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/executor/nodeBitmapIndexscan.c,v 1.13 2005/12/02 20:03:40 tgl Exp $
*
*-------------------------------------------------------------------------
*/
/*
* We do not open or lock the base relation here. We assume that an
- * ancestor BitmapHeapScan node is holding AccessShareLock on the heap
- * relation throughout the execution of the plan tree.
+ * ancestor BitmapHeapScan node is holding AccessShareLock (or better)
+ * on the heap relation throughout the execution of the plan tree.
*/
indexstate->ss.ss_currentRelation = NULL;
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/executor/nodeIndexscan.c,v 1.107 2005/11/25 19:47:49 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/executor/nodeIndexscan.c,v 1.108 2005/12/02 20:03:40 tgl Exp $
*
*-------------------------------------------------------------------------
*/
/*
* close the heap relation.
- *
- * Currently, we do not release the AccessShareLock acquired by
- * ExecInitIndexScan. This lock should be held till end of transaction.
- * (There is a faction that considers this too much locking, however.)
*/
- heap_close(relation, NoLock);
+ ExecCloseScanRelation(relation);
}
/* ----------------------------------------------------------------
ExecInitIndexScan(IndexScan *node, EState *estate)
{
IndexScanState *indexstate;
- RangeTblEntry *rtentry;
- Index relid;
- Oid reloid;
Relation currentRelation;
/*
}
/*
- * open the base relation and acquire AccessShareLock on it.
+ * open the base relation and acquire appropriate lock on it.
*/
- relid = node->scan.scanrelid;
- rtentry = rt_fetch(relid, estate->es_range_table);
- reloid = rtentry->relid;
-
- currentRelation = heap_open(reloid, AccessShareLock);
+ currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid);
indexstate->ss.ss_currentRelation = currentRelation;
indexstate->ss.ss_currentScanDesc = NULL; /* no heap scan here */
/*
* open the index relation and initialize relation and scan descriptors.
* Note we acquire no locks here; the index machinery does its own locks
- * and unlocks. (We rely on having AccessShareLock on the parent table to
+ * and unlocks. (We rely on having a lock on the parent table to
* ensure the index won't go away!)
*/
indexstate->iss_RelationDesc = index_open(node->indexid);
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/executor/nodeSeqscan.c,v 1.55 2005/11/25 04:24:48 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/executor/nodeSeqscan.c,v 1.56 2005/12/02 20:03:40 tgl Exp $
*
*-------------------------------------------------------------------------
*/
static void
InitScanRelation(SeqScanState *node, EState *estate)
{
- Index relid;
- List *rangeTable;
- RangeTblEntry *rtentry;
- Oid reloid;
Relation currentRelation;
HeapScanDesc currentScanDesc;
/*
* get the relation object id from the relid'th entry in the range table,
- * open that relation and initialize the scan state.
- *
- * We acquire AccessShareLock for the duration of the scan.
+ * open that relation and acquire appropriate lock on it.
*/
- relid = ((SeqScan *) node->ps.plan)->scanrelid;
- rangeTable = estate->es_range_table;
- rtentry = rt_fetch(relid, rangeTable);
- reloid = rtentry->relid;
-
- currentRelation = heap_open(reloid, AccessShareLock);
+ currentRelation = ExecOpenScanRelation(estate,
+ ((SeqScan *) node->ps.plan)->scanrelid);
currentScanDesc = heap_beginscan(currentRelation,
estate->es_snapshot,
/*
* close the heap relation.
- *
- * Currently, we do not release the AccessShareLock acquired by
- * InitScanRelation. This lock should be held till end of transaction.
- * (There is a faction that considers this too much locking, however.)
*/
- heap_close(relation, NoLock);
+ ExecCloseScanRelation(relation);
}
/* ----------------------------------------------------------------
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/executor/nodeTidscan.c,v 1.45 2005/11/26 22:14:56 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/executor/nodeTidscan.c,v 1.46 2005/12/02 20:03:41 tgl Exp $
*
*-------------------------------------------------------------------------
*/
/*
* close the heap relation.
- *
- * Currently, we do not release the AccessShareLock acquired by
- * ExecInitTidScan. This lock should be held till end of transaction.
- * (There is a faction that considers this too much locking, however.)
*/
- heap_close(node->ss.ss_currentRelation, NoLock);
+ ExecCloseScanRelation(node->ss.ss_currentRelation);
}
/* ----------------------------------------------------------------
ExecInitTidScan(TidScan *node, EState *estate)
{
TidScanState *tidstate;
- RangeTblEntry *rtentry;
- Oid relid;
- Oid reloid;
Relation currentRelation;
/*
tidstate->tss_TidPtr = -1;
/*
- * open the base relation
- *
- * We acquire AccessShareLock for the duration of the scan.
+ * open the base relation and acquire appropriate lock on it.
*/
- relid = node->scan.scanrelid;
- rtentry = rt_fetch(relid, estate->es_range_table);
- reloid = rtentry->relid;
-
- currentRelation = heap_open(reloid, AccessShareLock);
+ currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid);
tidstate->ss.ss_currentRelation = currentRelation;
tidstate->ss.ss_currentScanDesc = NULL; /* no heap scan here */
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/executor/executor.h,v 1.121 2005/11/23 20:27:58 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/executor/executor.h,v 1.122 2005/12/02 20:03:42 tgl Exp $
*
*-------------------------------------------------------------------------
*/
TupleDesc tupDesc, bool shouldFree);
extern void ExecAssignScanTypeFromOuterPlan(ScanState *scanstate);
+extern Relation ExecOpenScanRelation(EState *estate, Index scanrelid);
+extern void ExecCloseScanRelation(Relation scanrel);
+
extern void ExecOpenIndices(ResultRelInfo *resultRelInfo);
extern void ExecCloseIndices(ResultRelInfo *resultRelInfo);
extern void ExecInsertIndexTuples(TupleTableSlot *slot, ItemPointer tupleid,
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/nodes/execnodes.h,v 1.145 2005/11/28 23:46:03 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/nodes/execnodes.h,v 1.146 2005/12/02 20:03:42 tgl Exp $
*
*-------------------------------------------------------------------------
*/
} EState;
+/* es_rowMarks is a list of these structs: */
+typedef struct ExecRowMark
+{
+ Relation relation; /* opened and RowShareLock'd relation */
+ Index rti; /* its range table index */
+ char resname[32]; /* name for its ctid junk attribute */
+} ExecRowMark;
+
+
/* ----------------------------------------------------------------
* Tuple Hash Tables
*
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