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execAmi.c File Reference
#include "postgres.h"
#include "access/amapi.h"
#include "access/htup_details.h"
#include "catalog/pg_class.h"
#include "executor/executor.h"
#include "executor/nodeAgg.h"
#include "executor/nodeAppend.h"
#include "executor/nodeBitmapAnd.h"
#include "executor/nodeBitmapHeapscan.h"
#include "executor/nodeBitmapIndexscan.h"
#include "executor/nodeBitmapOr.h"
#include "executor/nodeCtescan.h"
#include "executor/nodeCustom.h"
#include "executor/nodeForeignscan.h"
#include "executor/nodeFunctionscan.h"
#include "executor/nodeGather.h"
#include "executor/nodeGatherMerge.h"
#include "executor/nodeGroup.h"
#include "executor/nodeHash.h"
#include "executor/nodeHashjoin.h"
#include "executor/nodeIncrementalSort.h"
#include "executor/nodeIndexonlyscan.h"
#include "executor/nodeIndexscan.h"
#include "executor/nodeLimit.h"
#include "executor/nodeLockRows.h"
#include "executor/nodeMaterial.h"
#include "executor/nodeMemoize.h"
#include "executor/nodeMergeAppend.h"
#include "executor/nodeMergejoin.h"
#include "executor/nodeModifyTable.h"
#include "executor/nodeNamedtuplestorescan.h"
#include "executor/nodeNestloop.h"
#include "executor/nodeProjectSet.h"
#include "executor/nodeRecursiveunion.h"
#include "executor/nodeResult.h"
#include "executor/nodeSamplescan.h"
#include "executor/nodeSeqscan.h"
#include "executor/nodeSetOp.h"
#include "executor/nodeSort.h"
#include "executor/nodeSubplan.h"
#include "executor/nodeSubqueryscan.h"
#include "executor/nodeTableFuncscan.h"
#include "executor/nodeTidrangescan.h"
#include "executor/nodeTidscan.h"
#include "executor/nodeUnique.h"
#include "executor/nodeValuesscan.h"
#include "executor/nodeWindowAgg.h"
#include "executor/nodeWorktablescan.h"
#include "nodes/extensible.h"
#include "nodes/pathnodes.h"
#include "utils/syscache.h"
Include dependency graph for execAmi.c:

Go to the source code of this file.

Functions

static bool IndexSupportsBackwardScan (Oid indexid)
 
void ExecReScan (PlanState *node)
 
void ExecMarkPos (PlanState *node)
 
void ExecRestrPos (PlanState *node)
 
bool ExecSupportsMarkRestore (Path *pathnode)
 
bool ExecSupportsBackwardScan (Plan *node)
 
bool ExecMaterializesOutput (NodeTag plantype)
 

Function Documentation

◆ ExecMarkPos()

void ExecMarkPos ( PlanState node)

Definition at line 327 of file execAmi.c.

328{
329 switch (nodeTag(node))
330 {
331 case T_IndexScanState:
333 break;
334
335 case T_IndexOnlyScanState:
337 break;
338
339 case T_CustomScanState:
341 break;
342
343 case T_MaterialState:
345 break;
346
347 case T_SortState:
348 ExecSortMarkPos((SortState *) node);
349 break;
350
351 case T_ResultState:
353 break;
354
355 default:
356 /* don't make hard error unless caller asks to restore... */
357 elog(DEBUG2, "unrecognized node type: %d", (int) nodeTag(node));
358 break;
359 }
360}
#define DEBUG2
Definition: elog.h:29
#define elog(elevel,...)
Definition: elog.h:226
void ExecCustomMarkPos(CustomScanState *node)
Definition: nodeCustom.c:139
void ExecIndexOnlyMarkPos(IndexOnlyScanState *node)
void ExecIndexMarkPos(IndexScanState *node)
void ExecMaterialMarkPos(MaterialState *node)
Definition: nodeMaterial.c:262
void ExecResultMarkPos(ResultState *node)
Definition: nodeResult.c:146
void ExecSortMarkPos(SortState *node)
Definition: nodeSort.c:329
#define nodeTag(nodeptr)
Definition: nodes.h:139

References DEBUG2, elog, ExecCustomMarkPos(), ExecIndexMarkPos(), ExecIndexOnlyMarkPos(), ExecMaterialMarkPos(), ExecResultMarkPos(), ExecSortMarkPos(), and nodeTag.

Referenced by ExecMergeJoin(), and ExecResultMarkPos().

◆ ExecMaterializesOutput()

bool ExecMaterializesOutput ( NodeTag  plantype)

Definition at line 636 of file execAmi.c.

637{
638 switch (plantype)
639 {
640 case T_Material:
641 case T_FunctionScan:
642 case T_TableFuncScan:
643 case T_CteScan:
644 case T_NamedTuplestoreScan:
645 case T_WorkTableScan:
646 case T_Sort:
647 return true;
648
649 default:
650 break;
651 }
652
653 return false;
654}

Referenced by build_subplan(), consider_parallel_nestloop(), cost_subplan(), and match_unsorted_outer().

◆ ExecReScan()

void ExecReScan ( PlanState node)

Definition at line 77 of file execAmi.c.

78{
79 /* If collecting timing stats, update them */
80 if (node->instrument)
82
83 /*
84 * If we have changed parameters, propagate that info.
85 *
86 * Note: ExecReScanSetParamPlan() can add bits to node->chgParam,
87 * corresponding to the output param(s) that the InitPlan will update.
88 * Since we make only one pass over the list, that means that an InitPlan
89 * can depend on the output param(s) of a sibling InitPlan only if that
90 * sibling appears earlier in the list. This is workable for now given
91 * the limited ways in which one InitPlan could depend on another, but
92 * eventually we might need to work harder (or else make the planner
93 * enlarge the extParam/allParam sets to include the params of depended-on
94 * InitPlans).
95 */
96 if (node->chgParam != NULL)
97 {
98 ListCell *l;
99
100 foreach(l, node->initPlan)
101 {
102 SubPlanState *sstate = (SubPlanState *) lfirst(l);
103 PlanState *splan = sstate->planstate;
104
105 if (splan->plan->extParam != NULL) /* don't care about child
106 * local Params */
107 UpdateChangedParamSet(splan, node->chgParam);
108 if (splan->chgParam != NULL)
109 ExecReScanSetParamPlan(sstate, node);
110 }
111 foreach(l, node->subPlan)
112 {
113 SubPlanState *sstate = (SubPlanState *) lfirst(l);
114 PlanState *splan = sstate->planstate;
115
116 if (splan->plan->extParam != NULL)
117 UpdateChangedParamSet(splan, node->chgParam);
118 }
119 /* Well. Now set chgParam for child trees. */
120 if (outerPlanState(node) != NULL)
122 if (innerPlanState(node) != NULL)
124 }
125
126 /* Call expression callbacks */
127 if (node->ps_ExprContext)
129
130 /* And do node-type-specific processing */
131 switch (nodeTag(node))
132 {
133 case T_ResultState:
135 break;
136
137 case T_ProjectSetState:
139 break;
140
141 case T_ModifyTableState:
143 break;
144
145 case T_AppendState:
147 break;
148
149 case T_MergeAppendState:
151 break;
152
153 case T_RecursiveUnionState:
155 break;
156
157 case T_BitmapAndState:
159 break;
160
161 case T_BitmapOrState:
163 break;
164
165 case T_SeqScanState:
167 break;
168
169 case T_SampleScanState:
171 break;
172
173 case T_GatherState:
175 break;
176
177 case T_GatherMergeState:
179 break;
180
181 case T_IndexScanState:
183 break;
184
185 case T_IndexOnlyScanState:
187 break;
188
189 case T_BitmapIndexScanState:
191 break;
192
193 case T_BitmapHeapScanState:
195 break;
196
197 case T_TidScanState:
199 break;
200
201 case T_TidRangeScanState:
203 break;
204
205 case T_SubqueryScanState:
207 break;
208
209 case T_FunctionScanState:
211 break;
212
213 case T_TableFuncScanState:
215 break;
216
217 case T_ValuesScanState:
219 break;
220
221 case T_CteScanState:
223 break;
224
225 case T_NamedTuplestoreScanState:
227 break;
228
229 case T_WorkTableScanState:
231 break;
232
233 case T_ForeignScanState:
235 break;
236
237 case T_CustomScanState:
239 break;
240
241 case T_NestLoopState:
243 break;
244
245 case T_MergeJoinState:
247 break;
248
249 case T_HashJoinState:
251 break;
252
253 case T_MaterialState:
255 break;
256
257 case T_MemoizeState:
259 break;
260
261 case T_SortState:
262 ExecReScanSort((SortState *) node);
263 break;
264
265 case T_IncrementalSortState:
267 break;
268
269 case T_GroupState:
270 ExecReScanGroup((GroupState *) node);
271 break;
272
273 case T_AggState:
274 ExecReScanAgg((AggState *) node);
275 break;
276
277 case T_WindowAggState:
279 break;
280
281 case T_UniqueState:
283 break;
284
285 case T_HashState:
286 ExecReScanHash((HashState *) node);
287 break;
288
289 case T_SetOpState:
290 ExecReScanSetOp((SetOpState *) node);
291 break;
292
293 case T_LockRowsState:
295 break;
296
297 case T_LimitState:
298 ExecReScanLimit((LimitState *) node);
299 break;
300
301 default:
302 elog(ERROR, "unrecognized node type: %d", (int) nodeTag(node));
303 break;
304 }
305
306 if (node->chgParam != NULL)
307 {
308 bms_free(node->chgParam);
309 node->chgParam = NULL;
310 }
311}
void bms_free(Bitmapset *a)
Definition: bitmapset.c:239
#define ERROR
Definition: elog.h:39
void ReScanExprContext(ExprContext *econtext)
Definition: execUtils.c:444
void UpdateChangedParamSet(PlanState *node, Bitmapset *newchg)
Definition: execUtils.c:911
#define outerPlanState(node)
Definition: execnodes.h:1255
#define innerPlanState(node)
Definition: execnodes.h:1254
void InstrEndLoop(Instrumentation *instr)
Definition: instrument.c:140
void ExecReScanAgg(AggState *node)
Definition: nodeAgg.c:4466
void ExecReScanAppend(AppendState *node)
Definition: nodeAppend.c:421
void ExecReScanBitmapAnd(BitmapAndState *node)
void ExecReScanBitmapHeapScan(BitmapHeapScanState *node)
void ExecReScanBitmapIndexScan(BitmapIndexScanState *node)
void ExecReScanBitmapOr(BitmapOrState *node)
Definition: nodeBitmapOr.c:219
void ExecReScanCteScan(CteScanState *node)
Definition: nodeCtescan.c:307
void ExecReScanCustomScan(CustomScanState *node)
Definition: nodeCustom.c:132
void ExecReScanForeignScan(ForeignScanState *node)
void ExecReScanFunctionScan(FunctionScanState *node)
void ExecReScanGatherMerge(GatherMergeState *node)
void ExecReScanGather(GatherState *node)
Definition: nodeGather.c:442
void ExecReScanGroup(GroupState *node)
Definition: nodeGroup.c:235
void ExecReScanHash(HashState *node)
Definition: nodeHash.c:2375
void ExecReScanHashJoin(HashJoinState *node)
void ExecReScanIncrementalSort(IncrementalSortState *node)
void ExecReScanIndexOnlyScan(IndexOnlyScanState *node)
void ExecReScanIndexScan(IndexScanState *node)
void ExecReScanLimit(LimitState *node)
Definition: nodeLimit.c:541
void ExecReScanLockRows(LockRowsState *node)
Definition: nodeLockRows.c:399
void ExecReScanMaterial(MaterialState *node)
Definition: nodeMaterial.c:313
void ExecReScanMemoize(MemoizeState *node)
Definition: nodeMemoize.c:1139
void ExecReScanMergeAppend(MergeAppendState *node)
void ExecReScanMergeJoin(MergeJoinState *node)
void ExecReScanModifyTable(ModifyTableState *node)
void ExecReScanNamedTuplestoreScan(NamedTuplestoreScanState *node)
void ExecReScanNestLoop(NestLoopState *node)
Definition: nodeNestloop.c:381
void ExecReScanProjectSet(ProjectSetState *node)
void ExecReScanRecursiveUnion(RecursiveUnionState *node)
void ExecReScanResult(ResultState *node)
Definition: nodeResult.c:249
void ExecReScanSampleScan(SampleScanState *node)
void ExecReScanSeqScan(SeqScanState *node)
Definition: nodeSeqscan.c:317
void ExecReScanSetOp(SetOpState *node)
Definition: nodeSetOp.c:693
void ExecReScanSort(SortState *node)
Definition: nodeSort.c:362
void ExecReScanSetParamPlan(SubPlanState *node, PlanState *parent)
Definition: nodeSubplan.c:1299
void ExecReScanSubqueryScan(SubqueryScanState *node)
void ExecReScanTableFuncScan(TableFuncScanState *node)
void ExecReScanTidRangeScan(TidRangeScanState *node)
void ExecReScanTidScan(TidScanState *node)
Definition: nodeTidscan.c:447
void ExecReScanUnique(UniqueState *node)
Definition: nodeUnique.c:175
void ExecReScanValuesScan(ValuesScanState *node)
void ExecReScanWindowAgg(WindowAggState *node)
void ExecReScanWorkTableScan(WorkTableScanState *node)
#define lfirst(lc)
Definition: pg_list.h:172
Instrumentation * instrument
Definition: execnodes.h:1169
Plan * plan
Definition: execnodes.h:1159
List * subPlan
Definition: execnodes.h:1186
List * initPlan
Definition: execnodes.h:1184
Bitmapset * chgParam
Definition: execnodes.h:1191
ExprContext * ps_ExprContext
Definition: execnodes.h:1198
Bitmapset * extParam
Definition: plannodes.h:229
struct PlanState * planstate
Definition: execnodes.h:1006

References bms_free(), PlanState::chgParam, elog, ERROR, ExecReScanAgg(), ExecReScanAppend(), ExecReScanBitmapAnd(), ExecReScanBitmapHeapScan(), ExecReScanBitmapIndexScan(), ExecReScanBitmapOr(), ExecReScanCteScan(), ExecReScanCustomScan(), ExecReScanForeignScan(), ExecReScanFunctionScan(), ExecReScanGather(), ExecReScanGatherMerge(), ExecReScanGroup(), ExecReScanHash(), ExecReScanHashJoin(), ExecReScanIncrementalSort(), ExecReScanIndexOnlyScan(), ExecReScanIndexScan(), ExecReScanLimit(), ExecReScanLockRows(), ExecReScanMaterial(), ExecReScanMemoize(), ExecReScanMergeAppend(), ExecReScanMergeJoin(), ExecReScanModifyTable(), ExecReScanNamedTuplestoreScan(), ExecReScanNestLoop(), ExecReScanProjectSet(), ExecReScanRecursiveUnion(), ExecReScanResult(), ExecReScanSampleScan(), ExecReScanSeqScan(), ExecReScanSetOp(), ExecReScanSetParamPlan(), ExecReScanSort(), ExecReScanSubqueryScan(), ExecReScanTableFuncScan(), ExecReScanTidRangeScan(), ExecReScanTidScan(), ExecReScanUnique(), ExecReScanValuesScan(), ExecReScanWindowAgg(), ExecReScanWorkTableScan(), Plan::extParam, PlanState::initPlan, innerPlanState, InstrEndLoop(), PlanState::instrument, lfirst, nodeTag, outerPlanState, PlanState::plan, SubPlanState::planstate, PlanState::ps_ExprContext, ReScanExprContext(), PlanState::subPlan, and UpdateChangedParamSet().

Referenced by buildSubPlanHash(), ExecAsyncRequest(), ExecIndexOnlyScan(), ExecIndexScan(), ExecNestLoop(), ExecProcNode(), ExecReScanAgg(), ExecReScanAppend(), ExecReScanBitmapAnd(), ExecReScanBitmapHeapScan(), ExecReScanBitmapOr(), ExecReScanForeignScan(), ExecReScanGather(), ExecReScanGatherMerge(), ExecReScanGroup(), ExecReScanHash(), ExecReScanHashJoin(), ExecReScanIncrementalSort(), ExecReScanLimit(), ExecReScanLockRows(), ExecReScanMaterial(), ExecReScanMemoize(), ExecReScanMergeAppend(), ExecReScanMergeJoin(), ExecReScanNestLoop(), ExecReScanProjectSet(), ExecReScanRecursiveUnion(), ExecReScanResult(), ExecReScanSetOp(), ExecReScanSort(), ExecReScanSubqueryScan(), ExecReScanUnique(), ExecReScanWindowAgg(), ExecScanSubPlan(), ExecutorRewind(), MultiExecBitmapIndexScan(), and MultiExecProcNode().

◆ ExecRestrPos()

void ExecRestrPos ( PlanState node)

Definition at line 376 of file execAmi.c.

377{
378 switch (nodeTag(node))
379 {
380 case T_IndexScanState:
382 break;
383
384 case T_IndexOnlyScanState:
386 break;
387
388 case T_CustomScanState:
390 break;
391
392 case T_MaterialState:
394 break;
395
396 case T_SortState:
397 ExecSortRestrPos((SortState *) node);
398 break;
399
400 case T_ResultState:
402 break;
403
404 default:
405 elog(ERROR, "unrecognized node type: %d", (int) nodeTag(node));
406 break;
407 }
408}
void ExecCustomRestrPos(CustomScanState *node)
Definition: nodeCustom.c:150
void ExecIndexOnlyRestrPos(IndexOnlyScanState *node)
void ExecIndexRestrPos(IndexScanState *node)
void ExecMaterialRestrPos(MaterialState *node)
Definition: nodeMaterial.c:290
void ExecResultRestrPos(ResultState *node)
Definition: nodeResult.c:161
void ExecSortRestrPos(SortState *node)
Definition: nodeSort.c:347

References elog, ERROR, ExecCustomRestrPos(), ExecIndexOnlyRestrPos(), ExecIndexRestrPos(), ExecMaterialRestrPos(), ExecResultRestrPos(), ExecSortRestrPos(), and nodeTag.

Referenced by ExecMergeJoin(), and ExecResultRestrPos().

◆ ExecSupportsBackwardScan()

bool ExecSupportsBackwardScan ( Plan node)

Definition at line 511 of file execAmi.c.

512{
513 if (node == NULL)
514 return false;
515
516 /*
517 * Parallel-aware nodes return a subset of the tuples in each worker, and
518 * in general we can't expect to have enough bookkeeping state to know
519 * which ones we returned in this worker as opposed to some other worker.
520 */
521 if (node->parallel_aware)
522 return false;
523
524 switch (nodeTag(node))
525 {
526 case T_Result:
527 if (outerPlan(node) != NULL)
529 else
530 return false;
531
532 case T_Append:
533 {
534 ListCell *l;
535
536 /* With async, tuples may be interleaved, so can't back up. */
537 if (((Append *) node)->nasyncplans > 0)
538 return false;
539
540 foreach(l, ((Append *) node)->appendplans)
541 {
543 return false;
544 }
545 /* need not check tlist because Append doesn't evaluate it */
546 return true;
547 }
548
549 case T_SampleScan:
550 /* Simplify life for tablesample methods by disallowing this */
551 return false;
552
553 case T_Gather:
554 return false;
555
556 case T_IndexScan:
557 return IndexSupportsBackwardScan(((IndexScan *) node)->indexid);
558
559 case T_IndexOnlyScan:
560 return IndexSupportsBackwardScan(((IndexOnlyScan *) node)->indexid);
561
562 case T_SubqueryScan:
563 return ExecSupportsBackwardScan(((SubqueryScan *) node)->subplan);
564
565 case T_CustomScan:
566 if (((CustomScan *) node)->flags & CUSTOMPATH_SUPPORT_BACKWARD_SCAN)
567 return true;
568 return false;
569
570 case T_SeqScan:
571 case T_TidScan:
572 case T_TidRangeScan:
573 case T_FunctionScan:
574 case T_ValuesScan:
575 case T_CteScan:
576 case T_Material:
577 case T_Sort:
578 /* these don't evaluate tlist */
579 return true;
580
581 case T_IncrementalSort:
582
583 /*
584 * Unlike full sort, incremental sort keeps only a single group of
585 * tuples in memory, so it can't scan backwards.
586 */
587 return false;
588
589 case T_LockRows:
590 case T_Limit:
592
593 default:
594 return false;
595 }
596}
static bool IndexSupportsBackwardScan(Oid indexid)
Definition: execAmi.c:603
bool ExecSupportsBackwardScan(Plan *node)
Definition: execAmi.c:511
#define CUSTOMPATH_SUPPORT_BACKWARD_SCAN
Definition: extensible.h:84
#define outerPlan(node)
Definition: plannodes.h:241
bool parallel_aware
Definition: plannodes.h:193

References CUSTOMPATH_SUPPORT_BACKWARD_SCAN, ExecSupportsBackwardScan(), IndexSupportsBackwardScan(), lfirst, nodeTag, outerPlan, and Plan::parallel_aware.

Referenced by ExecSupportsBackwardScan(), PerformCursorOpen(), SPI_cursor_open_internal(), and standard_planner().

◆ ExecSupportsMarkRestore()

bool ExecSupportsMarkRestore ( Path pathnode)

Definition at line 418 of file execAmi.c.

419{
420 /*
421 * For consistency with the routines above, we do not examine the nodeTag
422 * but rather the pathtype, which is the Plan node type the Path would
423 * produce.
424 */
425 switch (pathnode->pathtype)
426 {
427 case T_IndexScan:
428 case T_IndexOnlyScan:
429
430 /*
431 * Not all index types support mark/restore.
432 */
433 return castNode(IndexPath, pathnode)->indexinfo->amcanmarkpos;
434
435 case T_Material:
436 case T_Sort:
437 return true;
438
439 case T_CustomScan:
441 return true;
442 return false;
443
444 case T_Result:
445
446 /*
447 * Result supports mark/restore iff it has a child plan that does.
448 *
449 * We have to be careful here because there is more than one Path
450 * type that can produce a Result plan node.
451 */
452 if (IsA(pathnode, ProjectionPath))
453 return ExecSupportsMarkRestore(((ProjectionPath *) pathnode)->subpath);
454 else if (IsA(pathnode, MinMaxAggPath))
455 return false; /* childless Result */
456 else if (IsA(pathnode, GroupResultPath))
457 return false; /* childless Result */
458 else
459 {
460 /* Simple RTE_RESULT base relation */
461 Assert(IsA(pathnode, Path));
462 return false; /* childless Result */
463 }
464
465 case T_Append:
466 {
467 AppendPath *appendPath = castNode(AppendPath, pathnode);
468
469 /*
470 * If there's exactly one child, then there will be no Append
471 * in the final plan, so we can handle mark/restore if the
472 * child plan node can.
473 */
474 if (list_length(appendPath->subpaths) == 1)
475 return ExecSupportsMarkRestore((Path *) linitial(appendPath->subpaths));
476 /* Otherwise, Append can't handle it */
477 return false;
478 }
479
480 case T_MergeAppend:
481 {
482 MergeAppendPath *mapath = castNode(MergeAppendPath, pathnode);
483
484 /*
485 * Like the Append case above, single-subpath MergeAppends
486 * won't be in the final plan, so just return the child's
487 * mark/restore ability.
488 */
489 if (list_length(mapath->subpaths) == 1)
490 return ExecSupportsMarkRestore((Path *) linitial(mapath->subpaths));
491 /* Otherwise, MergeAppend can't handle it */
492 return false;
493 }
494
495 default:
496 break;
497 }
498
499 return false;
500}
bool ExecSupportsMarkRestore(Path *pathnode)
Definition: execAmi.c:418
#define CUSTOMPATH_SUPPORT_MARK_RESTORE
Definition: extensible.h:85
Assert(PointerIsAligned(start, uint64))
Datum subpath(PG_FUNCTION_ARGS)
Definition: ltree_op.c:311
#define IsA(nodeptr, _type_)
Definition: nodes.h:164
#define castNode(_type_, nodeptr)
Definition: nodes.h:182
static int list_length(const List *l)
Definition: pg_list.h:152
#define linitial(l)
Definition: pg_list.h:178
List * subpaths
Definition: pathnodes.h:2069
NodeTag pathtype
Definition: pathnodes.h:1762

References Assert(), castNode, CUSTOMPATH_SUPPORT_MARK_RESTORE, ExecSupportsMarkRestore(), IsA, linitial, list_length(), Path::pathtype, subpath(), AppendPath::subpaths, and MergeAppendPath::subpaths.

Referenced by ExecSupportsMarkRestore(), and final_cost_mergejoin().

◆ IndexSupportsBackwardScan()

static bool IndexSupportsBackwardScan ( Oid  indexid)
static

Definition at line 603 of file execAmi.c.

604{
605 bool result;
606 HeapTuple ht_idxrel;
607 Form_pg_class idxrelrec;
608 IndexAmRoutine *amroutine;
609
610 /* Fetch the pg_class tuple of the index relation */
611 ht_idxrel = SearchSysCache1(RELOID, ObjectIdGetDatum(indexid));
612 if (!HeapTupleIsValid(ht_idxrel))
613 elog(ERROR, "cache lookup failed for relation %u", indexid);
614 idxrelrec = (Form_pg_class) GETSTRUCT(ht_idxrel);
615
616 /* Fetch the index AM's API struct */
617 amroutine = GetIndexAmRoutineByAmId(idxrelrec->relam, false);
618
619 result = amroutine->amcanbackward;
620
621 pfree(amroutine);
622 ReleaseSysCache(ht_idxrel);
623
624 return result;
625}
IndexAmRoutine * GetIndexAmRoutineByAmId(Oid amoid, bool noerror)
Definition: amapi.c:56
#define HeapTupleIsValid(tuple)
Definition: htup.h:78
static void * GETSTRUCT(const HeapTupleData *tuple)
Definition: htup_details.h:728
void pfree(void *pointer)
Definition: mcxt.c:2146
FormData_pg_class * Form_pg_class
Definition: pg_class.h:156
static Datum ObjectIdGetDatum(Oid X)
Definition: postgres.h:257
bool amcanbackward
Definition: amapi.h:254
void ReleaseSysCache(HeapTuple tuple)
Definition: syscache.c:269
HeapTuple SearchSysCache1(int cacheId, Datum key1)
Definition: syscache.c:221

References IndexAmRoutine::amcanbackward, elog, ERROR, GetIndexAmRoutineByAmId(), GETSTRUCT(), HeapTupleIsValid, ObjectIdGetDatum(), pfree(), ReleaseSysCache(), and SearchSysCache1().

Referenced by ExecSupportsBackwardScan().