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indexam.c
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1 /*-------------------------------------------------------------------------
2  *
3  * indexam.c
4  * general index access method routines
5  *
6  * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
7  * Portions Copyright (c) 1994, Regents of the University of California
8  *
9  *
10  * IDENTIFICATION
11  * src/backend/access/index/indexam.c
12  *
13  * INTERFACE ROUTINES
14  * index_open - open an index relation by relation OID
15  * index_close - close an index relation
16  * index_beginscan - start a scan of an index with amgettuple
17  * index_beginscan_bitmap - start a scan of an index with amgetbitmap
18  * index_rescan - restart a scan of an index
19  * index_endscan - end a scan
20  * index_insert - insert an index tuple into a relation
21  * index_markpos - mark a scan position
22  * index_restrpos - restore a scan position
23  * index_parallelscan_estimate - estimate shared memory for parallel scan
24  * index_parallelscan_initialize - initialize parallel scan
25  * index_parallelrescan - (re)start a parallel scan of an index
26  * index_beginscan_parallel - join parallel index scan
27  * index_getnext_tid - get the next TID from a scan
28  * index_fetch_heap - get the scan's next heap tuple
29  * index_getnext_slot - get the next tuple from a scan
30  * index_getbitmap - get all tuples from a scan
31  * index_bulk_delete - bulk deletion of index tuples
32  * index_vacuum_cleanup - post-deletion cleanup of an index
33  * index_can_return - does index support index-only scans?
34  * index_getprocid - get a support procedure OID
35  * index_getprocinfo - get a support procedure's lookup info
36  *
37  * NOTES
38  * This file contains the index_ routines which used
39  * to be a scattered collection of stuff in access/genam.
40  *
41  *-------------------------------------------------------------------------
42  */
43 
44 #include "postgres.h"
45 
46 #include "access/amapi.h"
47 #include "access/heapam.h"
48 #include "access/reloptions.h"
49 #include "access/relscan.h"
50 #include "access/tableam.h"
51 #include "access/transam.h"
52 #include "access/xlog.h"
53 #include "catalog/index.h"
54 #include "catalog/pg_amproc.h"
55 #include "catalog/pg_type.h"
56 #include "commands/defrem.h"
57 #include "nodes/makefuncs.h"
58 #include "pgstat.h"
59 #include "storage/bufmgr.h"
60 #include "storage/lmgr.h"
61 #include "storage/predicate.h"
62 #include "utils/ruleutils.h"
63 #include "utils/snapmgr.h"
64 #include "utils/syscache.h"
65 
66 
67 /* ----------------------------------------------------------------
68  * macros used in index_ routines
69  *
70  * Note: the ReindexIsProcessingIndex() check in RELATION_CHECKS is there
71  * to check that we don't try to scan or do retail insertions into an index
72  * that is currently being rebuilt or pending rebuild. This helps to catch
73  * things that don't work when reindexing system catalogs. The assertion
74  * doesn't prevent the actual rebuild because we don't use RELATION_CHECKS
75  * when calling the index AM's ambuild routine, and there is no reason for
76  * ambuild to call its subsidiary routines through this file.
77  * ----------------------------------------------------------------
78  */
79 #define RELATION_CHECKS \
80 ( \
81  AssertMacro(RelationIsValid(indexRelation)), \
82  AssertMacro(PointerIsValid(indexRelation->rd_indam)), \
83  AssertMacro(!ReindexIsProcessingIndex(RelationGetRelid(indexRelation))) \
84 )
85 
86 #define SCAN_CHECKS \
87 ( \
88  AssertMacro(IndexScanIsValid(scan)), \
89  AssertMacro(RelationIsValid(scan->indexRelation)), \
90  AssertMacro(PointerIsValid(scan->indexRelation->rd_indam)) \
91 )
92 
93 #define CHECK_REL_PROCEDURE(pname) \
94 do { \
95  if (indexRelation->rd_indam->pname == NULL) \
96  elog(ERROR, "function \"%s\" is not defined for index \"%s\"", \
97  CppAsString(pname), RelationGetRelationName(indexRelation)); \
98 } while(0)
99 
100 #define CHECK_SCAN_PROCEDURE(pname) \
101 do { \
102  if (scan->indexRelation->rd_indam->pname == NULL) \
103  elog(ERROR, "function \"%s\" is not defined for index \"%s\"", \
104  CppAsString(pname), RelationGetRelationName(scan->indexRelation)); \
105 } while(0)
106 
107 static IndexScanDesc index_beginscan_internal(Relation indexRelation,
108  int nkeys, int norderbys, Snapshot snapshot,
109  ParallelIndexScanDesc pscan, bool temp_snap);
110 
111 
112 /* ----------------------------------------------------------------
113  * index_ interface functions
114  * ----------------------------------------------------------------
115  */
116 
117 /* ----------------
118  * index_open - open an index relation by relation OID
119  *
120  * If lockmode is not "NoLock", the specified kind of lock is
121  * obtained on the index. (Generally, NoLock should only be
122  * used if the caller knows it has some appropriate lock on the
123  * index already.)
124  *
125  * An error is raised if the index does not exist.
126  *
127  * This is a convenience routine adapted for indexscan use.
128  * Some callers may prefer to use relation_open directly.
129  * ----------------
130  */
131 Relation
132 index_open(Oid relationId, LOCKMODE lockmode)
133 {
134  Relation r;
135 
136  r = relation_open(relationId, lockmode);
137 
138  if (r->rd_rel->relkind != RELKIND_INDEX &&
139  r->rd_rel->relkind != RELKIND_PARTITIONED_INDEX)
140  ereport(ERROR,
141  (errcode(ERRCODE_WRONG_OBJECT_TYPE),
142  errmsg("\"%s\" is not an index",
144 
145  return r;
146 }
147 
148 /* ----------------
149  * index_close - close an index relation
150  *
151  * If lockmode is not "NoLock", we then release the specified lock.
152  *
153  * Note that it is often sensible to hold a lock beyond index_close;
154  * in that case, the lock is released automatically at xact end.
155  * ----------------
156  */
157 void
158 index_close(Relation relation, LOCKMODE lockmode)
159 {
160  LockRelId relid = relation->rd_lockInfo.lockRelId;
161 
162  Assert(lockmode >= NoLock && lockmode < MAX_LOCKMODES);
163 
164  /* The relcache does the real work... */
165  RelationClose(relation);
166 
167  if (lockmode != NoLock)
168  UnlockRelationId(&relid, lockmode);
169 }
170 
171 /* ----------------
172  * index_insert - insert an index tuple into a relation
173  * ----------------
174  */
175 bool
176 index_insert(Relation indexRelation,
177  Datum *values,
178  bool *isnull,
179  ItemPointer heap_t_ctid,
180  Relation heapRelation,
181  IndexUniqueCheck checkUnique,
182  bool indexUnchanged,
183  IndexInfo *indexInfo)
184 {
186  CHECK_REL_PROCEDURE(aminsert);
187 
188  if (!(indexRelation->rd_indam->ampredlocks))
189  CheckForSerializableConflictIn(indexRelation,
190  (ItemPointer) NULL,
192 
193  return indexRelation->rd_indam->aminsert(indexRelation, values, isnull,
194  heap_t_ctid, heapRelation,
195  checkUnique, indexUnchanged,
196  indexInfo);
197 }
198 
199 /*
200  * index_beginscan - start a scan of an index with amgettuple
201  *
202  * Caller must be holding suitable locks on the heap and the index.
203  */
206  Relation indexRelation,
207  Snapshot snapshot,
208  int nkeys, int norderbys)
209 {
210  IndexScanDesc scan;
211 
212  Assert(snapshot != InvalidSnapshot);
213 
214  scan = index_beginscan_internal(indexRelation, nkeys, norderbys, snapshot, NULL, false);
215 
216  /*
217  * Save additional parameters into the scandesc. Everything else was set
218  * up by RelationGetIndexScan.
219  */
220  scan->heapRelation = heapRelation;
221  scan->xs_snapshot = snapshot;
222 
223  /* prepare to fetch index matches from table */
224  scan->xs_heapfetch = table_index_fetch_begin(heapRelation);
225 
226  return scan;
227 }
228 
229 /*
230  * index_beginscan_bitmap - start a scan of an index with amgetbitmap
231  *
232  * As above, caller had better be holding some lock on the parent heap
233  * relation, even though it's not explicitly mentioned here.
234  */
237  Snapshot snapshot,
238  int nkeys)
239 {
240  IndexScanDesc scan;
241 
242  Assert(snapshot != InvalidSnapshot);
243 
244  scan = index_beginscan_internal(indexRelation, nkeys, 0, snapshot, NULL, false);
245 
246  /*
247  * Save additional parameters into the scandesc. Everything else was set
248  * up by RelationGetIndexScan.
249  */
250  scan->xs_snapshot = snapshot;
251 
252  return scan;
253 }
254 
255 /*
256  * index_beginscan_internal --- common code for index_beginscan variants
257  */
258 static IndexScanDesc
260  int nkeys, int norderbys, Snapshot snapshot,
261  ParallelIndexScanDesc pscan, bool temp_snap)
262 {
263  IndexScanDesc scan;
264 
266  CHECK_REL_PROCEDURE(ambeginscan);
267 
268  if (!(indexRelation->rd_indam->ampredlocks))
269  PredicateLockRelation(indexRelation, snapshot);
270 
271  /*
272  * We hold a reference count to the relcache entry throughout the scan.
273  */
274  RelationIncrementReferenceCount(indexRelation);
275 
276  /*
277  * Tell the AM to open a scan.
278  */
279  scan = indexRelation->rd_indam->ambeginscan(indexRelation, nkeys,
280  norderbys);
281  /* Initialize information for parallel scan. */
282  scan->parallel_scan = pscan;
283  scan->xs_temp_snap = temp_snap;
284 
285  return scan;
286 }
287 
288 /* ----------------
289  * index_rescan - (re)start a scan of an index
290  *
291  * During a restart, the caller may specify a new set of scankeys and/or
292  * orderbykeys; but the number of keys cannot differ from what index_beginscan
293  * was told. (Later we might relax that to "must not exceed", but currently
294  * the index AMs tend to assume that scan->numberOfKeys is what to believe.)
295  * To restart the scan without changing keys, pass NULL for the key arrays.
296  * (Of course, keys *must* be passed on the first call, unless
297  * scan->numberOfKeys is zero.)
298  * ----------------
299  */
300 void
302  ScanKey keys, int nkeys,
303  ScanKey orderbys, int norderbys)
304 {
305  SCAN_CHECKS;
306  CHECK_SCAN_PROCEDURE(amrescan);
307 
308  Assert(nkeys == scan->numberOfKeys);
309  Assert(norderbys == scan->numberOfOrderBys);
310 
311  /* Release resources (like buffer pins) from table accesses */
312  if (scan->xs_heapfetch)
314 
315  scan->kill_prior_tuple = false; /* for safety */
316  scan->xs_heap_continue = false;
317 
318  scan->indexRelation->rd_indam->amrescan(scan, keys, nkeys,
319  orderbys, norderbys);
320 }
321 
322 /* ----------------
323  * index_endscan - end a scan
324  * ----------------
325  */
326 void
328 {
329  SCAN_CHECKS;
330  CHECK_SCAN_PROCEDURE(amendscan);
331 
332  /* Release resources (like buffer pins) from table accesses */
333  if (scan->xs_heapfetch)
334  {
336  scan->xs_heapfetch = NULL;
337  }
338 
339  /* End the AM's scan */
340  scan->indexRelation->rd_indam->amendscan(scan);
341 
342  /* Release index refcount acquired by index_beginscan */
344 
345  if (scan->xs_temp_snap)
347 
348  /* Release the scan data structure itself */
349  IndexScanEnd(scan);
350 }
351 
352 /* ----------------
353  * index_markpos - mark a scan position
354  * ----------------
355  */
356 void
358 {
359  SCAN_CHECKS;
360  CHECK_SCAN_PROCEDURE(ammarkpos);
361 
362  scan->indexRelation->rd_indam->ammarkpos(scan);
363 }
364 
365 /* ----------------
366  * index_restrpos - restore a scan position
367  *
368  * NOTE: this only restores the internal scan state of the index AM. See
369  * comments for ExecRestrPos().
370  *
371  * NOTE: For heap, in the presence of HOT chains, mark/restore only works
372  * correctly if the scan's snapshot is MVCC-safe; that ensures that there's at
373  * most one returnable tuple in each HOT chain, and so restoring the prior
374  * state at the granularity of the index AM is sufficient. Since the only
375  * current user of mark/restore functionality is nodeMergejoin.c, this
376  * effectively means that merge-join plans only work for MVCC snapshots. This
377  * could be fixed if necessary, but for now it seems unimportant.
378  * ----------------
379  */
380 void
382 {
384 
385  SCAN_CHECKS;
386  CHECK_SCAN_PROCEDURE(amrestrpos);
387 
388  /* release resources (like buffer pins) from table accesses */
389  if (scan->xs_heapfetch)
391 
392  scan->kill_prior_tuple = false; /* for safety */
393  scan->xs_heap_continue = false;
394 
395  scan->indexRelation->rd_indam->amrestrpos(scan);
396 }
397 
398 /*
399  * index_parallelscan_estimate - estimate shared memory for parallel scan
400  *
401  * Currently, we don't pass any information to the AM-specific estimator,
402  * so it can probably only return a constant. In the future, we might need
403  * to pass more information.
404  */
405 Size
407 {
408  Size nbytes;
409 
410  Assert(snapshot != InvalidSnapshot);
411 
413 
414  nbytes = offsetof(ParallelIndexScanDescData, ps_snapshot_data);
415  nbytes = add_size(nbytes, EstimateSnapshotSpace(snapshot));
416  nbytes = MAXALIGN(nbytes);
417 
418  /*
419  * If amestimateparallelscan is not provided, assume there is no
420  * AM-specific data needed. (It's hard to believe that could work, but
421  * it's easy enough to cater to it here.)
422  */
423  if (indexRelation->rd_indam->amestimateparallelscan != NULL)
424  nbytes = add_size(nbytes,
425  indexRelation->rd_indam->amestimateparallelscan());
426 
427  return nbytes;
428 }
429 
430 /*
431  * index_parallelscan_initialize - initialize parallel scan
432  *
433  * We initialize both the ParallelIndexScanDesc proper and the AM-specific
434  * information which follows it.
435  *
436  * This function calls access method specific initialization routine to
437  * initialize am specific information. Call this just once in the leader
438  * process; then, individual workers attach via index_beginscan_parallel.
439  */
440 void
441 index_parallelscan_initialize(Relation heapRelation, Relation indexRelation,
442  Snapshot snapshot, ParallelIndexScanDesc target)
443 {
444  Size offset;
445 
446  Assert(snapshot != InvalidSnapshot);
447 
449 
450  offset = add_size(offsetof(ParallelIndexScanDescData, ps_snapshot_data),
451  EstimateSnapshotSpace(snapshot));
452  offset = MAXALIGN(offset);
453 
454  target->ps_relid = RelationGetRelid(heapRelation);
455  target->ps_indexid = RelationGetRelid(indexRelation);
456  target->ps_offset = offset;
457  SerializeSnapshot(snapshot, target->ps_snapshot_data);
458 
459  /* aminitparallelscan is optional; assume no-op if not provided by AM */
460  if (indexRelation->rd_indam->aminitparallelscan != NULL)
461  {
462  void *amtarget;
463 
464  amtarget = OffsetToPointer(target, offset);
465  indexRelation->rd_indam->aminitparallelscan(amtarget);
466  }
467 }
468 
469 /* ----------------
470  * index_parallelrescan - (re)start a parallel scan of an index
471  * ----------------
472  */
473 void
475 {
476  SCAN_CHECKS;
477 
478  if (scan->xs_heapfetch)
480 
481  /* amparallelrescan is optional; assume no-op if not provided by AM */
482  if (scan->indexRelation->rd_indam->amparallelrescan != NULL)
484 }
485 
486 /*
487  * index_beginscan_parallel - join parallel index scan
488  *
489  * Caller must be holding suitable locks on the heap and the index.
490  */
492 index_beginscan_parallel(Relation heaprel, Relation indexrel, int nkeys,
493  int norderbys, ParallelIndexScanDesc pscan)
494 {
495  Snapshot snapshot;
496  IndexScanDesc scan;
497 
498  Assert(RelationGetRelid(heaprel) == pscan->ps_relid);
499  snapshot = RestoreSnapshot(pscan->ps_snapshot_data);
500  RegisterSnapshot(snapshot);
501  scan = index_beginscan_internal(indexrel, nkeys, norderbys, snapshot,
502  pscan, true);
503 
504  /*
505  * Save additional parameters into the scandesc. Everything else was set
506  * up by index_beginscan_internal.
507  */
508  scan->heapRelation = heaprel;
509  scan->xs_snapshot = snapshot;
510 
511  /* prepare to fetch index matches from table */
512  scan->xs_heapfetch = table_index_fetch_begin(heaprel);
513 
514  return scan;
515 }
516 
517 /* ----------------
518  * index_getnext_tid - get the next TID from a scan
519  *
520  * The result is the next TID satisfying the scan keys,
521  * or NULL if no more matching tuples exist.
522  * ----------------
523  */
526 {
527  bool found;
528 
529  SCAN_CHECKS;
530  CHECK_SCAN_PROCEDURE(amgettuple);
531 
532  /* XXX: we should assert that a snapshot is pushed or registered */
534 
535  /*
536  * The AM's amgettuple proc finds the next index entry matching the scan
537  * keys, and puts the TID into scan->xs_heaptid. It should also set
538  * scan->xs_recheck and possibly scan->xs_itup/scan->xs_hitup, though we
539  * pay no attention to those fields here.
540  */
541  found = scan->indexRelation->rd_indam->amgettuple(scan, direction);
542 
543  /* Reset kill flag immediately for safety */
544  scan->kill_prior_tuple = false;
545  scan->xs_heap_continue = false;
546 
547  /* If we're out of index entries, we're done */
548  if (!found)
549  {
550  /* release resources (like buffer pins) from table accesses */
551  if (scan->xs_heapfetch)
553 
554  return NULL;
555  }
557 
559 
560  /* Return the TID of the tuple we found. */
561  return &scan->xs_heaptid;
562 }
563 
564 /* ----------------
565  * index_fetch_heap - get the scan's next heap tuple
566  *
567  * The result is a visible heap tuple associated with the index TID most
568  * recently fetched by index_getnext_tid, or NULL if no more matching tuples
569  * exist. (There can be more than one matching tuple because of HOT chains,
570  * although when using an MVCC snapshot it should be impossible for more than
571  * one such tuple to exist.)
572  *
573  * On success, the buffer containing the heap tup is pinned (the pin will be
574  * dropped in a future index_getnext_tid, index_fetch_heap or index_endscan
575  * call).
576  *
577  * Note: caller must check scan->xs_recheck, and perform rechecking of the
578  * scan keys if required. We do not do that here because we don't have
579  * enough information to do it efficiently in the general case.
580  * ----------------
581  */
582 bool
584 {
585  bool all_dead = false;
586  bool found;
587 
588  found = table_index_fetch_tuple(scan->xs_heapfetch, &scan->xs_heaptid,
589  scan->xs_snapshot, slot,
590  &scan->xs_heap_continue, &all_dead);
591 
592  if (found)
594 
595  /*
596  * If we scanned a whole HOT chain and found only dead tuples, tell index
597  * AM to kill its entry for that TID (this will take effect in the next
598  * amgettuple call, in index_getnext_tid). We do not do this when in
599  * recovery because it may violate MVCC to do so. See comments in
600  * RelationGetIndexScan().
601  */
602  if (!scan->xactStartedInRecovery)
603  scan->kill_prior_tuple = all_dead;
604 
605  return found;
606 }
607 
608 /* ----------------
609  * index_getnext_slot - get the next tuple from a scan
610  *
611  * The result is true if a tuple satisfying the scan keys and the snapshot was
612  * found, false otherwise. The tuple is stored in the specified slot.
613  *
614  * On success, resources (like buffer pins) are likely to be held, and will be
615  * dropped by a future index_getnext_tid, index_fetch_heap or index_endscan
616  * call).
617  *
618  * Note: caller must check scan->xs_recheck, and perform rechecking of the
619  * scan keys if required. We do not do that here because we don't have
620  * enough information to do it efficiently in the general case.
621  * ----------------
622  */
623 bool
625 {
626  for (;;)
627  {
628  if (!scan->xs_heap_continue)
629  {
630  ItemPointer tid;
631 
632  /* Time to fetch the next TID from the index */
633  tid = index_getnext_tid(scan, direction);
634 
635  /* If we're out of index entries, we're done */
636  if (tid == NULL)
637  break;
638 
639  Assert(ItemPointerEquals(tid, &scan->xs_heaptid));
640  }
641 
642  /*
643  * Fetch the next (or only) visible heap tuple for this index entry.
644  * If we don't find anything, loop around and grab the next TID from
645  * the index.
646  */
648  if (index_fetch_heap(scan, slot))
649  return true;
650  }
651 
652  return false;
653 }
654 
655 /* ----------------
656  * index_getbitmap - get all tuples at once from an index scan
657  *
658  * Adds the TIDs of all heap tuples satisfying the scan keys to a bitmap.
659  * Since there's no interlock between the index scan and the eventual heap
660  * access, this is only safe to use with MVCC-based snapshots: the heap
661  * item slot could have been replaced by a newer tuple by the time we get
662  * to it.
663  *
664  * Returns the number of matching tuples found. (Note: this might be only
665  * approximate, so it should only be used for statistical purposes.)
666  * ----------------
667  */
668 int64
670 {
671  int64 ntids;
672 
673  SCAN_CHECKS;
674  CHECK_SCAN_PROCEDURE(amgetbitmap);
675 
676  /* just make sure this is false... */
677  scan->kill_prior_tuple = false;
678 
679  /*
680  * have the am's getbitmap proc do all the work.
681  */
682  ntids = scan->indexRelation->rd_indam->amgetbitmap(scan, bitmap);
683 
685 
686  return ntids;
687 }
688 
689 /* ----------------
690  * index_bulk_delete - do mass deletion of index entries
691  *
692  * callback routine tells whether a given main-heap tuple is
693  * to be deleted
694  *
695  * return value is an optional palloc'd struct of statistics
696  * ----------------
697  */
700  IndexBulkDeleteResult *istat,
702  void *callback_state)
703 {
704  Relation indexRelation = info->index;
705 
707  CHECK_REL_PROCEDURE(ambulkdelete);
708 
709  return indexRelation->rd_indam->ambulkdelete(info, istat,
710  callback, callback_state);
711 }
712 
713 /* ----------------
714  * index_vacuum_cleanup - do post-deletion cleanup of an index
715  *
716  * return value is an optional palloc'd struct of statistics
717  * ----------------
718  */
721  IndexBulkDeleteResult *istat)
722 {
723  Relation indexRelation = info->index;
724 
726  CHECK_REL_PROCEDURE(amvacuumcleanup);
727 
728  return indexRelation->rd_indam->amvacuumcleanup(info, istat);
729 }
730 
731 /* ----------------
732  * index_can_return
733  *
734  * Does the index access method support index-only scans for the given
735  * column?
736  * ----------------
737  */
738 bool
739 index_can_return(Relation indexRelation, int attno)
740 {
742 
743  /* amcanreturn is optional; assume false if not provided by AM */
744  if (indexRelation->rd_indam->amcanreturn == NULL)
745  return false;
746 
747  return indexRelation->rd_indam->amcanreturn(indexRelation, attno);
748 }
749 
750 /* ----------------
751  * index_getprocid
752  *
753  * Index access methods typically require support routines that are
754  * not directly the implementation of any WHERE-clause query operator
755  * and so cannot be kept in pg_amop. Instead, such routines are kept
756  * in pg_amproc. These registered procedure OIDs are assigned numbers
757  * according to a convention established by the access method.
758  * The general index code doesn't know anything about the routines
759  * involved; it just builds an ordered list of them for
760  * each attribute on which an index is defined.
761  *
762  * As of Postgres 8.3, support routines within an operator family
763  * are further subdivided by the "left type" and "right type" of the
764  * query operator(s) that they support. The "default" functions for a
765  * particular indexed attribute are those with both types equal to
766  * the index opclass' opcintype (note that this is subtly different
767  * from the indexed attribute's own type: it may be a binary-compatible
768  * type instead). Only the default functions are stored in relcache
769  * entries --- access methods can use the syscache to look up non-default
770  * functions.
771  *
772  * This routine returns the requested default procedure OID for a
773  * particular indexed attribute.
774  * ----------------
775  */
779  uint16 procnum)
780 {
781  RegProcedure *loc;
782  int nproc;
783  int procindex;
784 
785  nproc = irel->rd_indam->amsupport;
786 
787  Assert(procnum > 0 && procnum <= (uint16) nproc);
788 
789  procindex = (nproc * (attnum - 1)) + (procnum - 1);
790 
791  loc = irel->rd_support;
792 
793  Assert(loc != NULL);
794 
795  return loc[procindex];
796 }
797 
798 /* ----------------
799  * index_getprocinfo
800  *
801  * This routine allows index AMs to keep fmgr lookup info for
802  * support procs in the relcache. As above, only the "default"
803  * functions for any particular indexed attribute are cached.
804  *
805  * Note: the return value points into cached data that will be lost during
806  * any relcache rebuild! Therefore, either use the callinfo right away,
807  * or save it only after having acquired some type of lock on the index rel.
808  * ----------------
809  */
810 FmgrInfo *
813  uint16 procnum)
814 {
815  FmgrInfo *locinfo;
816  int nproc;
817  int optsproc;
818  int procindex;
819 
820  nproc = irel->rd_indam->amsupport;
821  optsproc = irel->rd_indam->amoptsprocnum;
822 
823  Assert(procnum > 0 && procnum <= (uint16) nproc);
824 
825  procindex = (nproc * (attnum - 1)) + (procnum - 1);
826 
827  locinfo = irel->rd_supportinfo;
828 
829  Assert(locinfo != NULL);
830 
831  locinfo += procindex;
832 
833  /* Initialize the lookup info if first time through */
834  if (locinfo->fn_oid == InvalidOid)
835  {
836  RegProcedure *loc = irel->rd_support;
837  RegProcedure procId;
838 
839  Assert(loc != NULL);
840 
841  procId = loc[procindex];
842 
843  /*
844  * Complain if function was not found during IndexSupportInitialize.
845  * This should not happen unless the system tables contain bogus
846  * entries for the index opclass. (If an AM wants to allow a support
847  * function to be optional, it can use index_getprocid.)
848  */
849  if (!RegProcedureIsValid(procId))
850  elog(ERROR, "missing support function %d for attribute %d of index \"%s\"",
851  procnum, attnum, RelationGetRelationName(irel));
852 
853  fmgr_info_cxt(procId, locinfo, irel->rd_indexcxt);
854 
855  if (procnum != optsproc)
856  {
857  /* Initialize locinfo->fn_expr with opclass options Const */
858  bytea **attoptions = RelationGetIndexAttOptions(irel, false);
860 
861  set_fn_opclass_options(locinfo, attoptions[attnum - 1]);
862 
863  MemoryContextSwitchTo(oldcxt);
864  }
865  }
866 
867  return locinfo;
868 }
869 
870 /* ----------------
871  * index_store_float8_orderby_distances
872  *
873  * Convert AM distance function's results (that can be inexact)
874  * to ORDER BY types and save them into xs_orderbyvals/xs_orderbynulls
875  * for a possible recheck.
876  * ----------------
877  */
878 void
880  IndexOrderByDistance *distances,
881  bool recheckOrderBy)
882 {
883  int i;
884 
885  Assert(distances || !recheckOrderBy);
886 
887  scan->xs_recheckorderby = recheckOrderBy;
888 
889  for (i = 0; i < scan->numberOfOrderBys; i++)
890  {
891  if (orderByTypes[i] == FLOAT8OID)
892  {
893 #ifndef USE_FLOAT8_BYVAL
894  /* must free any old value to avoid memory leakage */
895  if (!scan->xs_orderbynulls[i])
897 #endif
898  if (distances && !distances[i].isnull)
899  {
900  scan->xs_orderbyvals[i] = Float8GetDatum(distances[i].value);
901  scan->xs_orderbynulls[i] = false;
902  }
903  else
904  {
905  scan->xs_orderbyvals[i] = (Datum) 0;
906  scan->xs_orderbynulls[i] = true;
907  }
908  }
909  else if (orderByTypes[i] == FLOAT4OID)
910  {
911  /* convert distance function's result to ORDER BY type */
912  if (distances && !distances[i].isnull)
913  {
914  scan->xs_orderbyvals[i] = Float4GetDatum((float4) distances[i].value);
915  scan->xs_orderbynulls[i] = false;
916  }
917  else
918  {
919  scan->xs_orderbyvals[i] = (Datum) 0;
920  scan->xs_orderbynulls[i] = true;
921  }
922  }
923  else
924  {
925  /*
926  * If the ordering operator's return value is anything else, we
927  * don't know how to convert the float8 bound calculated by the
928  * distance function to that. The executor won't actually need
929  * the order by values we return here, if there are no lossy
930  * results, so only insist on converting if the *recheck flag is
931  * set.
932  */
933  if (scan->xs_recheckorderby)
934  elog(ERROR, "ORDER BY operator must return float8 or float4 if the distance function is lossy");
935  scan->xs_orderbynulls[i] = true;
936  }
937  }
938 }
939 
940 /* ----------------
941  * index_opclass_options
942  *
943  * Parse opclass-specific options for index column.
944  * ----------------
945  */
946 bytea *
948  bool validate)
949 {
950  int amoptsprocnum = indrel->rd_indam->amoptsprocnum;
951  Oid procid = InvalidOid;
952  FmgrInfo *procinfo;
953  local_relopts relopts;
954 
955  /* fetch options support procedure if specified */
956  if (amoptsprocnum != 0)
957  procid = index_getprocid(indrel, attnum, amoptsprocnum);
958 
959  if (!OidIsValid(procid))
960  {
961  Oid opclass;
962  Datum indclassDatum;
963  oidvector *indclass;
964  bool isnull;
965 
966  if (!DatumGetPointer(attoptions))
967  return NULL; /* ok, no options, no procedure */
968 
969  /*
970  * Report an error if the opclass's options-parsing procedure does not
971  * exist but the opclass options are specified.
972  */
973  indclassDatum = SysCacheGetAttr(INDEXRELID, indrel->rd_indextuple,
974  Anum_pg_index_indclass, &isnull);
975  Assert(!isnull);
976  indclass = (oidvector *) DatumGetPointer(indclassDatum);
977  opclass = indclass->values[attnum - 1];
978 
979  ereport(ERROR,
980  (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
981  errmsg("operator class %s has no options",
982  generate_opclass_name(opclass))));
983  }
984 
985  init_local_reloptions(&relopts, 0);
986 
987  procinfo = index_getprocinfo(indrel, attnum, amoptsprocnum);
988 
989  (void) FunctionCall1(procinfo, PointerGetDatum(&relopts));
990 
991  return build_local_reloptions(&relopts, attoptions, validate);
992 }
int16 AttrNumber
Definition: attnum.h:21
#define InvalidBlockNumber
Definition: block.h:33
static Datum values[MAXATTR]
Definition: bootstrap.c:156
#define OffsetToPointer(base, offset)
Definition: c.h:756
unsigned short uint16
Definition: c.h:489
#define RegProcedureIsValid(p)
Definition: c.h:761
#define MAXALIGN(LEN)
Definition: c.h:795
regproc RegProcedure
Definition: c.h:634
float float4
Definition: c.h:613
#define OidIsValid(objectId)
Definition: c.h:759
size_t Size
Definition: c.h:589
int errcode(int sqlerrcode)
Definition: elog.c:858
int errmsg(const char *fmt,...)
Definition: elog.c:1069
#define ERROR
Definition: elog.h:39
#define ereport(elevel,...)
Definition: elog.h:149
void set_fn_opclass_options(FmgrInfo *flinfo, bytea *options)
Definition: fmgr.c:2057
void fmgr_info_cxt(Oid functionId, FmgrInfo *finfo, MemoryContext mcxt)
Definition: fmgr.c:137
Datum Float8GetDatum(float8 X)
Definition: fmgr.c:1803
#define FunctionCall1(flinfo, arg1)
Definition: fmgr.h:660
void IndexScanEnd(IndexScanDesc scan)
Definition: genam.c:145
bool(* IndexBulkDeleteCallback)(ItemPointer itemptr, void *state)
Definition: genam.h:86
IndexUniqueCheck
Definition: genam.h:115
bool index_getnext_slot(IndexScanDesc scan, ScanDirection direction, TupleTableSlot *slot)
Definition: indexam.c:624
IndexBulkDeleteResult * index_vacuum_cleanup(IndexVacuumInfo *info, IndexBulkDeleteResult *istat)
Definition: indexam.c:720
Size index_parallelscan_estimate(Relation indexRelation, Snapshot snapshot)
Definition: indexam.c:406
#define CHECK_REL_PROCEDURE(pname)
Definition: indexam.c:93
bool index_insert(Relation indexRelation, Datum *values, bool *isnull, ItemPointer heap_t_ctid, Relation heapRelation, IndexUniqueCheck checkUnique, bool indexUnchanged, IndexInfo *indexInfo)
Definition: indexam.c:176
void index_restrpos(IndexScanDesc scan)
Definition: indexam.c:381
static IndexScanDesc index_beginscan_internal(Relation indexRelation, int nkeys, int norderbys, Snapshot snapshot, ParallelIndexScanDesc pscan, bool temp_snap)
Definition: indexam.c:259
IndexScanDesc index_beginscan_parallel(Relation heaprel, Relation indexrel, int nkeys, int norderbys, ParallelIndexScanDesc pscan)
Definition: indexam.c:492
IndexScanDesc index_beginscan_bitmap(Relation indexRelation, Snapshot snapshot, int nkeys)
Definition: indexam.c:236
void index_close(Relation relation, LOCKMODE lockmode)
Definition: indexam.c:158
bool index_can_return(Relation indexRelation, int attno)
Definition: indexam.c:739
ItemPointer index_getnext_tid(IndexScanDesc scan, ScanDirection direction)
Definition: indexam.c:525
FmgrInfo * index_getprocinfo(Relation irel, AttrNumber attnum, uint16 procnum)
Definition: indexam.c:811
IndexScanDesc index_beginscan(Relation heapRelation, Relation indexRelation, Snapshot snapshot, int nkeys, int norderbys)
Definition: indexam.c:205
RegProcedure index_getprocid(Relation irel, AttrNumber attnum, uint16 procnum)
Definition: indexam.c:777
bool index_fetch_heap(IndexScanDesc scan, TupleTableSlot *slot)
Definition: indexam.c:583
void index_markpos(IndexScanDesc scan)
Definition: indexam.c:357
void index_endscan(IndexScanDesc scan)
Definition: indexam.c:327
#define RELATION_CHECKS
Definition: indexam.c:79
IndexBulkDeleteResult * index_bulk_delete(IndexVacuumInfo *info, IndexBulkDeleteResult *istat, IndexBulkDeleteCallback callback, void *callback_state)
Definition: indexam.c:699
void index_parallelscan_initialize(Relation heapRelation, Relation indexRelation, Snapshot snapshot, ParallelIndexScanDesc target)
Definition: indexam.c:441
Relation index_open(Oid relationId, LOCKMODE lockmode)
Definition: indexam.c:132
bytea * index_opclass_options(Relation indrel, AttrNumber attnum, Datum attoptions, bool validate)
Definition: indexam.c:947
int64 index_getbitmap(IndexScanDesc scan, TIDBitmap *bitmap)
Definition: indexam.c:669
void index_parallelrescan(IndexScanDesc scan)
Definition: indexam.c:474
void index_rescan(IndexScanDesc scan, ScanKey keys, int nkeys, ScanKey orderbys, int norderbys)
Definition: indexam.c:301
#define CHECK_SCAN_PROCEDURE(pname)
Definition: indexam.c:100
#define SCAN_CHECKS
Definition: indexam.c:86
void index_store_float8_orderby_distances(IndexScanDesc scan, Oid *orderByTypes, IndexOrderByDistance *distances, bool recheckOrderBy)
Definition: indexam.c:879
static struct @143 value
int i
Definition: isn.c:73
bool ItemPointerEquals(ItemPointer pointer1, ItemPointer pointer2)
Definition: itemptr.c:35
static bool ItemPointerIsValid(const ItemPointerData *pointer)
Definition: itemptr.h:83
Assert(fmt[strlen(fmt) - 1] !='\n')
void UnlockRelationId(LockRelId *relid, LOCKMODE lockmode)
Definition: lmgr.c:213
#define MAX_LOCKMODES
Definition: lock.h:82
int LOCKMODE
Definition: lockdefs.h:26
#define NoLock
Definition: lockdefs.h:34
void pfree(void *pointer)
Definition: mcxt.c:1436
static MemoryContext MemoryContextSwitchTo(MemoryContext context)
Definition: palloc.h:138
int16 attnum
Definition: pg_attribute.h:83
#define pgstat_count_index_tuples(rel, n)
Definition: pgstat.h:546
#define pgstat_count_heap_fetch(rel)
Definition: pgstat.h:536
static Datum PointerGetDatum(const void *X)
Definition: postgres.h:322
static Datum Float4GetDatum(float4 X)
Definition: postgres.h:475
uintptr_t Datum
Definition: postgres.h:64
static Pointer DatumGetPointer(Datum X)
Definition: postgres.h:312
#define InvalidOid
Definition: postgres_ext.h:36
unsigned int Oid
Definition: postgres_ext.h:31
void CheckForSerializableConflictIn(Relation relation, ItemPointer tid, BlockNumber blkno)
Definition: predicate.c:4242
void PredicateLockRelation(Relation relation, Snapshot snapshot)
Definition: predicate.c:2490
#define RelationGetRelid(relation)
Definition: rel.h:501
#define RelationGetRelationName(relation)
Definition: rel.h:535
void RelationDecrementReferenceCount(Relation rel)
Definition: relcache.c:2140
void RelationIncrementReferenceCount(Relation rel)
Definition: relcache.c:2127
bytea ** RelationGetIndexAttOptions(Relation relation, bool copy)
Definition: relcache.c:5815
void RelationClose(Relation relation)
Definition: relcache.c:2160
void init_local_reloptions(local_relopts *relopts, Size relopt_struct_size)
Definition: reloptions.c:736
void * build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
Definition: reloptions.c:1947
char * generate_opclass_name(Oid opclass)
Definition: ruleutils.c:11399
ScanDirection
Definition: sdir.h:23
Size add_size(Size s1, Size s2)
Definition: shmem.c:502
TransactionId RecentXmin
Definition: snapmgr.c:114
void SerializeSnapshot(Snapshot snapshot, char *start_address)
Definition: snapmgr.c:2147
void UnregisterSnapshot(Snapshot snapshot)
Definition: snapmgr.c:871
Snapshot RestoreSnapshot(char *start_address)
Definition: snapmgr.c:2206
Snapshot RegisterSnapshot(Snapshot snapshot)
Definition: snapmgr.c:829
Size EstimateSnapshotSpace(Snapshot snapshot)
Definition: snapmgr.c:2123
#define IsMVCCSnapshot(snapshot)
Definition: snapmgr.h:96
#define InvalidSnapshot
Definition: snapshot.h:123
Relation relation_open(Oid relationId, LOCKMODE lockmode)
Definition: relation.c:48
Definition: fmgr.h:57
Oid fn_oid
Definition: fmgr.h:59
amvacuumcleanup_function amvacuumcleanup
Definition: amapi.h:263
amestimateparallelscan_function amestimateparallelscan
Definition: amapi.h:280
amrestrpos_function amrestrpos
Definition: amapi.h:277
aminsert_function aminsert
Definition: amapi.h:261
amendscan_function amendscan
Definition: amapi.h:275
uint16 amoptsprocnum
Definition: amapi.h:218
amparallelrescan_function amparallelrescan
Definition: amapi.h:282
bool ampredlocks
Definition: amapi.h:240
uint16 amsupport
Definition: amapi.h:216
amgettuple_function amgettuple
Definition: amapi.h:273
amcanreturn_function amcanreturn
Definition: amapi.h:264
amgetbitmap_function amgetbitmap
Definition: amapi.h:274
ambulkdelete_function ambulkdelete
Definition: amapi.h:262
ammarkpos_function ammarkpos
Definition: amapi.h:276
ambeginscan_function ambeginscan
Definition: amapi.h:271
amrescan_function amrescan
Definition: amapi.h:272
aminitparallelscan_function aminitparallelscan
Definition: amapi.h:281
bool xs_heap_continue
Definition: relscan.h:148
struct ParallelIndexScanDescData * parallel_scan
Definition: relscan.h:166
bool * xs_orderbynulls
Definition: relscan.h:162
IndexFetchTableData * xs_heapfetch
Definition: relscan.h:150
int numberOfOrderBys
Definition: relscan.h:121
bool xactStartedInRecovery
Definition: relscan.h:130
bool xs_recheckorderby
Definition: relscan.h:163
bool kill_prior_tuple
Definition: relscan.h:128
Relation indexRelation
Definition: relscan.h:118
ItemPointerData xs_heaptid
Definition: relscan.h:147
struct SnapshotData * xs_snapshot
Definition: relscan.h:119
Relation heapRelation
Definition: relscan.h:117
Datum * xs_orderbyvals
Definition: relscan.h:161
Relation index
Definition: genam.h:46
LockRelId lockRelId
Definition: rel.h:45
Definition: rel.h:38
char ps_snapshot_data[FLEXIBLE_ARRAY_MEMBER]
Definition: relscan.h:175
struct IndexAmRoutine * rd_indam
Definition: rel.h:202
LockInfoData rd_lockInfo
Definition: rel.h:113
RegProcedure * rd_support
Definition: rel.h:205
struct HeapTupleData * rd_indextuple
Definition: rel.h:190
MemoryContext rd_indexcxt
Definition: rel.h:200
struct FmgrInfo * rd_supportinfo
Definition: rel.h:206
Form_pg_class rd_rel
Definition: rel.h:110
Definition: c.h:710
Oid values[FLEXIBLE_ARRAY_MEMBER]
Definition: c.h:717
Definition: c.h:671
Datum SysCacheGetAttr(int cacheId, HeapTuple tup, AttrNumber attributeNumber, bool *isNull)
Definition: syscache.c:1078
@ INDEXRELID
Definition: syscache.h:66
static IndexFetchTableData * table_index_fetch_begin(Relation rel)
Definition: tableam.h:1163
static void table_index_fetch_reset(struct IndexFetchTableData *scan)
Definition: tableam.h:1173
static void table_index_fetch_end(struct IndexFetchTableData *scan)
Definition: tableam.h:1182
static bool table_index_fetch_tuple(struct IndexFetchTableData *scan, ItemPointer tid, Snapshot snapshot, TupleTableSlot *slot, bool *call_again, bool *all_dead)
Definition: tableam.h:1212
static void callback(struct sockaddr *addr, struct sockaddr *mask, void *unused)
Definition: test_ifaddrs.c:46
#define TransactionIdIsValid(xid)
Definition: transam.h:41