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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) 1996-2020, 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  IndexInfo *indexInfo)
183 {
185  CHECK_REL_PROCEDURE(aminsert);
186 
187  if (!(indexRelation->rd_indam->ampredlocks))
188  CheckForSerializableConflictIn(indexRelation,
189  (ItemPointer) NULL,
191 
192  return indexRelation->rd_indam->aminsert(indexRelation, values, isnull,
193  heap_t_ctid, heapRelation,
194  checkUnique, indexInfo);
195 }
196 
197 /*
198  * index_beginscan - start a scan of an index with amgettuple
199  *
200  * Caller must be holding suitable locks on the heap and the index.
201  */
204  Relation indexRelation,
205  Snapshot snapshot,
206  int nkeys, int norderbys)
207 {
208  IndexScanDesc scan;
209 
210  scan = index_beginscan_internal(indexRelation, nkeys, norderbys, snapshot, NULL, false);
211 
212  /*
213  * Save additional parameters into the scandesc. Everything else was set
214  * up by RelationGetIndexScan.
215  */
216  scan->heapRelation = heapRelation;
217  scan->xs_snapshot = snapshot;
218 
219  /* prepare to fetch index matches from table */
220  scan->xs_heapfetch = table_index_fetch_begin(heapRelation);
221 
222  return scan;
223 }
224 
225 /*
226  * index_beginscan_bitmap - start a scan of an index with amgetbitmap
227  *
228  * As above, caller had better be holding some lock on the parent heap
229  * relation, even though it's not explicitly mentioned here.
230  */
233  Snapshot snapshot,
234  int nkeys)
235 {
236  IndexScanDesc scan;
237 
238  scan = index_beginscan_internal(indexRelation, nkeys, 0, snapshot, NULL, false);
239 
240  /*
241  * Save additional parameters into the scandesc. Everything else was set
242  * up by RelationGetIndexScan.
243  */
244  scan->xs_snapshot = snapshot;
245 
246  return scan;
247 }
248 
249 /*
250  * index_beginscan_internal --- common code for index_beginscan variants
251  */
252 static IndexScanDesc
254  int nkeys, int norderbys, Snapshot snapshot,
255  ParallelIndexScanDesc pscan, bool temp_snap)
256 {
257  IndexScanDesc scan;
258 
260  CHECK_REL_PROCEDURE(ambeginscan);
261 
262  if (!(indexRelation->rd_indam->ampredlocks))
263  PredicateLockRelation(indexRelation, snapshot);
264 
265  /*
266  * We hold a reference count to the relcache entry throughout the scan.
267  */
268  RelationIncrementReferenceCount(indexRelation);
269 
270  /*
271  * Tell the AM to open a scan.
272  */
273  scan = indexRelation->rd_indam->ambeginscan(indexRelation, nkeys,
274  norderbys);
275  /* Initialize information for parallel scan. */
276  scan->parallel_scan = pscan;
277  scan->xs_temp_snap = temp_snap;
278 
279  return scan;
280 }
281 
282 /* ----------------
283  * index_rescan - (re)start a scan of an index
284  *
285  * During a restart, the caller may specify a new set of scankeys and/or
286  * orderbykeys; but the number of keys cannot differ from what index_beginscan
287  * was told. (Later we might relax that to "must not exceed", but currently
288  * the index AMs tend to assume that scan->numberOfKeys is what to believe.)
289  * To restart the scan without changing keys, pass NULL for the key arrays.
290  * (Of course, keys *must* be passed on the first call, unless
291  * scan->numberOfKeys is zero.)
292  * ----------------
293  */
294 void
296  ScanKey keys, int nkeys,
297  ScanKey orderbys, int norderbys)
298 {
299  SCAN_CHECKS;
300  CHECK_SCAN_PROCEDURE(amrescan);
301 
302  Assert(nkeys == scan->numberOfKeys);
303  Assert(norderbys == scan->numberOfOrderBys);
304 
305  /* Release resources (like buffer pins) from table accesses */
306  if (scan->xs_heapfetch)
308 
309  scan->kill_prior_tuple = false; /* for safety */
310  scan->xs_heap_continue = false;
311 
312  scan->indexRelation->rd_indam->amrescan(scan, keys, nkeys,
313  orderbys, norderbys);
314 }
315 
316 /* ----------------
317  * index_endscan - end a scan
318  * ----------------
319  */
320 void
322 {
323  SCAN_CHECKS;
324  CHECK_SCAN_PROCEDURE(amendscan);
325 
326  /* Release resources (like buffer pins) from table accesses */
327  if (scan->xs_heapfetch)
328  {
330  scan->xs_heapfetch = NULL;
331  }
332 
333  /* End the AM's scan */
334  scan->indexRelation->rd_indam->amendscan(scan);
335 
336  /* Release index refcount acquired by index_beginscan */
338 
339  if (scan->xs_temp_snap)
341 
342  /* Release the scan data structure itself */
343  IndexScanEnd(scan);
344 }
345 
346 /* ----------------
347  * index_markpos - mark a scan position
348  * ----------------
349  */
350 void
352 {
353  SCAN_CHECKS;
354  CHECK_SCAN_PROCEDURE(ammarkpos);
355 
356  scan->indexRelation->rd_indam->ammarkpos(scan);
357 }
358 
359 /* ----------------
360  * index_restrpos - restore a scan position
361  *
362  * NOTE: this only restores the internal scan state of the index AM. See
363  * comments for ExecRestrPos().
364  *
365  * NOTE: For heap, in the presence of HOT chains, mark/restore only works
366  * correctly if the scan's snapshot is MVCC-safe; that ensures that there's at
367  * most one returnable tuple in each HOT chain, and so restoring the prior
368  * state at the granularity of the index AM is sufficient. Since the only
369  * current user of mark/restore functionality is nodeMergejoin.c, this
370  * effectively means that merge-join plans only work for MVCC snapshots. This
371  * could be fixed if necessary, but for now it seems unimportant.
372  * ----------------
373  */
374 void
376 {
378 
379  SCAN_CHECKS;
380  CHECK_SCAN_PROCEDURE(amrestrpos);
381 
382  /* release resources (like buffer pins) from table accesses */
383  if (scan->xs_heapfetch)
385 
386  scan->kill_prior_tuple = false; /* for safety */
387  scan->xs_heap_continue = false;
388 
389  scan->indexRelation->rd_indam->amrestrpos(scan);
390 }
391 
392 /*
393  * index_parallelscan_estimate - estimate shared memory for parallel scan
394  *
395  * Currently, we don't pass any information to the AM-specific estimator,
396  * so it can probably only return a constant. In the future, we might need
397  * to pass more information.
398  */
399 Size
401 {
402  Size nbytes;
403 
405 
406  nbytes = offsetof(ParallelIndexScanDescData, ps_snapshot_data);
407  nbytes = add_size(nbytes, EstimateSnapshotSpace(snapshot));
408  nbytes = MAXALIGN(nbytes);
409 
410  /*
411  * If amestimateparallelscan is not provided, assume there is no
412  * AM-specific data needed. (It's hard to believe that could work, but
413  * it's easy enough to cater to it here.)
414  */
415  if (indexRelation->rd_indam->amestimateparallelscan != NULL)
416  nbytes = add_size(nbytes,
417  indexRelation->rd_indam->amestimateparallelscan());
418 
419  return nbytes;
420 }
421 
422 /*
423  * index_parallelscan_initialize - initialize parallel scan
424  *
425  * We initialize both the ParallelIndexScanDesc proper and the AM-specific
426  * information which follows it.
427  *
428  * This function calls access method specific initialization routine to
429  * initialize am specific information. Call this just once in the leader
430  * process; then, individual workers attach via index_beginscan_parallel.
431  */
432 void
433 index_parallelscan_initialize(Relation heapRelation, Relation indexRelation,
434  Snapshot snapshot, ParallelIndexScanDesc target)
435 {
436  Size offset;
437 
439 
440  offset = add_size(offsetof(ParallelIndexScanDescData, ps_snapshot_data),
441  EstimateSnapshotSpace(snapshot));
442  offset = MAXALIGN(offset);
443 
444  target->ps_relid = RelationGetRelid(heapRelation);
445  target->ps_indexid = RelationGetRelid(indexRelation);
446  target->ps_offset = offset;
447  SerializeSnapshot(snapshot, target->ps_snapshot_data);
448 
449  /* aminitparallelscan is optional; assume no-op if not provided by AM */
450  if (indexRelation->rd_indam->aminitparallelscan != NULL)
451  {
452  void *amtarget;
453 
454  amtarget = OffsetToPointer(target, offset);
455  indexRelation->rd_indam->aminitparallelscan(amtarget);
456  }
457 }
458 
459 /* ----------------
460  * index_parallelrescan - (re)start a parallel scan of an index
461  * ----------------
462  */
463 void
465 {
466  SCAN_CHECKS;
467 
468  if (scan->xs_heapfetch)
470 
471  /* amparallelrescan is optional; assume no-op if not provided by AM */
472  if (scan->indexRelation->rd_indam->amparallelrescan != NULL)
474 }
475 
476 /*
477  * index_beginscan_parallel - join parallel index scan
478  *
479  * Caller must be holding suitable locks on the heap and the index.
480  */
482 index_beginscan_parallel(Relation heaprel, Relation indexrel, int nkeys,
483  int norderbys, ParallelIndexScanDesc pscan)
484 {
485  Snapshot snapshot;
486  IndexScanDesc scan;
487 
488  Assert(RelationGetRelid(heaprel) == pscan->ps_relid);
489  snapshot = RestoreSnapshot(pscan->ps_snapshot_data);
490  RegisterSnapshot(snapshot);
491  scan = index_beginscan_internal(indexrel, nkeys, norderbys, snapshot,
492  pscan, true);
493 
494  /*
495  * Save additional parameters into the scandesc. Everything else was set
496  * up by index_beginscan_internal.
497  */
498  scan->heapRelation = heaprel;
499  scan->xs_snapshot = snapshot;
500 
501  /* prepare to fetch index matches from table */
502  scan->xs_heapfetch = table_index_fetch_begin(heaprel);
503 
504  return scan;
505 }
506 
507 /* ----------------
508  * index_getnext_tid - get the next TID from a scan
509  *
510  * The result is the next TID satisfying the scan keys,
511  * or NULL if no more matching tuples exist.
512  * ----------------
513  */
516 {
517  bool found;
518 
519  SCAN_CHECKS;
520  CHECK_SCAN_PROCEDURE(amgettuple);
521 
523 
524  /*
525  * The AM's amgettuple proc finds the next index entry matching the scan
526  * keys, and puts the TID into scan->xs_heaptid. It should also set
527  * scan->xs_recheck and possibly scan->xs_itup/scan->xs_hitup, though we
528  * pay no attention to those fields here.
529  */
530  found = scan->indexRelation->rd_indam->amgettuple(scan, direction);
531 
532  /* Reset kill flag immediately for safety */
533  scan->kill_prior_tuple = false;
534  scan->xs_heap_continue = false;
535 
536  /* If we're out of index entries, we're done */
537  if (!found)
538  {
539  /* release resources (like buffer pins) from table accesses */
540  if (scan->xs_heapfetch)
542 
543  return NULL;
544  }
546 
548 
549  /* Return the TID of the tuple we found. */
550  return &scan->xs_heaptid;
551 }
552 
553 /* ----------------
554  * index_fetch_heap - get the scan's next heap tuple
555  *
556  * The result is a visible heap tuple associated with the index TID most
557  * recently fetched by index_getnext_tid, or NULL if no more matching tuples
558  * exist. (There can be more than one matching tuple because of HOT chains,
559  * although when using an MVCC snapshot it should be impossible for more than
560  * one such tuple to exist.)
561  *
562  * On success, the buffer containing the heap tup is pinned (the pin will be
563  * dropped in a future index_getnext_tid, index_fetch_heap or index_endscan
564  * call).
565  *
566  * Note: caller must check scan->xs_recheck, and perform rechecking of the
567  * scan keys if required. We do not do that here because we don't have
568  * enough information to do it efficiently in the general case.
569  * ----------------
570  */
571 bool
573 {
574  bool all_dead = false;
575  bool found;
576 
577  found = table_index_fetch_tuple(scan->xs_heapfetch, &scan->xs_heaptid,
578  scan->xs_snapshot, slot,
579  &scan->xs_heap_continue, &all_dead);
580 
581  if (found)
583 
584  /*
585  * If we scanned a whole HOT chain and found only dead tuples, tell index
586  * AM to kill its entry for that TID (this will take effect in the next
587  * amgettuple call, in index_getnext_tid). We do not do this when in
588  * recovery because it may violate MVCC to do so. See comments in
589  * RelationGetIndexScan().
590  */
591  if (!scan->xactStartedInRecovery)
592  scan->kill_prior_tuple = all_dead;
593 
594  return found;
595 }
596 
597 /* ----------------
598  * index_getnext_slot - get the next tuple from a scan
599  *
600  * The result is true if a tuple satisfying the scan keys and the snapshot was
601  * found, false otherwise. The tuple is stored in the specified slot.
602  *
603  * On success, resources (like buffer pins) are likely to be held, and will be
604  * dropped by a future index_getnext_tid, index_fetch_heap or index_endscan
605  * call).
606  *
607  * Note: caller must check scan->xs_recheck, and perform rechecking of the
608  * scan keys if required. We do not do that here because we don't have
609  * enough information to do it efficiently in the general case.
610  * ----------------
611  */
612 bool
614 {
615  for (;;)
616  {
617  if (!scan->xs_heap_continue)
618  {
619  ItemPointer tid;
620 
621  /* Time to fetch the next TID from the index */
622  tid = index_getnext_tid(scan, direction);
623 
624  /* If we're out of index entries, we're done */
625  if (tid == NULL)
626  break;
627 
628  Assert(ItemPointerEquals(tid, &scan->xs_heaptid));
629  }
630 
631  /*
632  * Fetch the next (or only) visible heap tuple for this index entry.
633  * If we don't find anything, loop around and grab the next TID from
634  * the index.
635  */
637  if (index_fetch_heap(scan, slot))
638  return true;
639  }
640 
641  return false;
642 }
643 
644 /* ----------------
645  * index_getbitmap - get all tuples at once from an index scan
646  *
647  * Adds the TIDs of all heap tuples satisfying the scan keys to a bitmap.
648  * Since there's no interlock between the index scan and the eventual heap
649  * access, this is only safe to use with MVCC-based snapshots: the heap
650  * item slot could have been replaced by a newer tuple by the time we get
651  * to it.
652  *
653  * Returns the number of matching tuples found. (Note: this might be only
654  * approximate, so it should only be used for statistical purposes.)
655  * ----------------
656  */
657 int64
659 {
660  int64 ntids;
661 
662  SCAN_CHECKS;
663  CHECK_SCAN_PROCEDURE(amgetbitmap);
664 
665  /* just make sure this is false... */
666  scan->kill_prior_tuple = false;
667 
668  /*
669  * have the am's getbitmap proc do all the work.
670  */
671  ntids = scan->indexRelation->rd_indam->amgetbitmap(scan, bitmap);
672 
674 
675  return ntids;
676 }
677 
678 /* ----------------
679  * index_bulk_delete - do mass deletion of index entries
680  *
681  * callback routine tells whether a given main-heap tuple is
682  * to be deleted
683  *
684  * return value is an optional palloc'd struct of statistics
685  * ----------------
686  */
689  IndexBulkDeleteResult *stats,
691  void *callback_state)
692 {
693  Relation indexRelation = info->index;
694 
696  CHECK_REL_PROCEDURE(ambulkdelete);
697 
698  return indexRelation->rd_indam->ambulkdelete(info, stats,
699  callback, callback_state);
700 }
701 
702 /* ----------------
703  * index_vacuum_cleanup - do post-deletion cleanup of an index
704  *
705  * return value is an optional palloc'd struct of statistics
706  * ----------------
707  */
710  IndexBulkDeleteResult *stats)
711 {
712  Relation indexRelation = info->index;
713 
715  CHECK_REL_PROCEDURE(amvacuumcleanup);
716 
717  return indexRelation->rd_indam->amvacuumcleanup(info, stats);
718 }
719 
720 /* ----------------
721  * index_can_return
722  *
723  * Does the index access method support index-only scans for the given
724  * column?
725  * ----------------
726  */
727 bool
728 index_can_return(Relation indexRelation, int attno)
729 {
731 
732  /* amcanreturn is optional; assume false if not provided by AM */
733  if (indexRelation->rd_indam->amcanreturn == NULL)
734  return false;
735 
736  return indexRelation->rd_indam->amcanreturn(indexRelation, attno);
737 }
738 
739 /* ----------------
740  * index_getprocid
741  *
742  * Index access methods typically require support routines that are
743  * not directly the implementation of any WHERE-clause query operator
744  * and so cannot be kept in pg_amop. Instead, such routines are kept
745  * in pg_amproc. These registered procedure OIDs are assigned numbers
746  * according to a convention established by the access method.
747  * The general index code doesn't know anything about the routines
748  * involved; it just builds an ordered list of them for
749  * each attribute on which an index is defined.
750  *
751  * As of Postgres 8.3, support routines within an operator family
752  * are further subdivided by the "left type" and "right type" of the
753  * query operator(s) that they support. The "default" functions for a
754  * particular indexed attribute are those with both types equal to
755  * the index opclass' opcintype (note that this is subtly different
756  * from the indexed attribute's own type: it may be a binary-compatible
757  * type instead). Only the default functions are stored in relcache
758  * entries --- access methods can use the syscache to look up non-default
759  * functions.
760  *
761  * This routine returns the requested default procedure OID for a
762  * particular indexed attribute.
763  * ----------------
764  */
768  uint16 procnum)
769 {
770  RegProcedure *loc;
771  int nproc;
772  int procindex;
773 
774  nproc = irel->rd_indam->amsupport;
775 
776  Assert(procnum > 0 && procnum <= (uint16) nproc);
777 
778  procindex = (nproc * (attnum - 1)) + (procnum - 1);
779 
780  loc = irel->rd_support;
781 
782  Assert(loc != NULL);
783 
784  return loc[procindex];
785 }
786 
787 /* ----------------
788  * index_getprocinfo
789  *
790  * This routine allows index AMs to keep fmgr lookup info for
791  * support procs in the relcache. As above, only the "default"
792  * functions for any particular indexed attribute are cached.
793  *
794  * Note: the return value points into cached data that will be lost during
795  * any relcache rebuild! Therefore, either use the callinfo right away,
796  * or save it only after having acquired some type of lock on the index rel.
797  * ----------------
798  */
799 FmgrInfo *
802  uint16 procnum)
803 {
804  FmgrInfo *locinfo;
805  int nproc;
806  int optsproc;
807  int procindex;
808 
809  nproc = irel->rd_indam->amsupport;
810  optsproc = irel->rd_indam->amoptsprocnum;
811 
812  Assert(procnum > 0 && procnum <= (uint16) nproc);
813 
814  procindex = (nproc * (attnum - 1)) + (procnum - 1);
815 
816  locinfo = irel->rd_supportinfo;
817 
818  Assert(locinfo != NULL);
819 
820  locinfo += procindex;
821 
822  /* Initialize the lookup info if first time through */
823  if (locinfo->fn_oid == InvalidOid)
824  {
825  RegProcedure *loc = irel->rd_support;
826  RegProcedure procId;
827 
828  Assert(loc != NULL);
829 
830  procId = loc[procindex];
831 
832  /*
833  * Complain if function was not found during IndexSupportInitialize.
834  * This should not happen unless the system tables contain bogus
835  * entries for the index opclass. (If an AM wants to allow a support
836  * function to be optional, it can use index_getprocid.)
837  */
838  if (!RegProcedureIsValid(procId))
839  elog(ERROR, "missing support function %d for attribute %d of index \"%s\"",
840  procnum, attnum, RelationGetRelationName(irel));
841 
842  fmgr_info_cxt(procId, locinfo, irel->rd_indexcxt);
843 
844  if (procnum != optsproc)
845  {
846  /* Initialize locinfo->fn_expr with opclass options Const */
847  bytea **attoptions = RelationGetIndexAttOptions(irel, false);
849 
850  set_fn_opclass_options(locinfo, attoptions[attnum - 1]);
851 
852  MemoryContextSwitchTo(oldcxt);
853  }
854  }
855 
856  return locinfo;
857 }
858 
859 /* ----------------
860  * index_store_float8_orderby_distances
861  *
862  * Convert AM distance function's results (that can be inexact)
863  * to ORDER BY types and save them into xs_orderbyvals/xs_orderbynulls
864  * for a possible recheck.
865  * ----------------
866  */
867 void
869  IndexOrderByDistance *distances,
870  bool recheckOrderBy)
871 {
872  int i;
873 
874  Assert(distances || !recheckOrderBy);
875 
876  scan->xs_recheckorderby = recheckOrderBy;
877 
878  for (i = 0; i < scan->numberOfOrderBys; i++)
879  {
880  if (orderByTypes[i] == FLOAT8OID)
881  {
882 #ifndef USE_FLOAT8_BYVAL
883  /* must free any old value to avoid memory leakage */
884  if (!scan->xs_orderbynulls[i])
886 #endif
887  if (distances && !distances[i].isnull)
888  {
889  scan->xs_orderbyvals[i] = Float8GetDatum(distances[i].value);
890  scan->xs_orderbynulls[i] = false;
891  }
892  else
893  {
894  scan->xs_orderbyvals[i] = (Datum) 0;
895  scan->xs_orderbynulls[i] = true;
896  }
897  }
898  else if (orderByTypes[i] == FLOAT4OID)
899  {
900  /* convert distance function's result to ORDER BY type */
901  if (distances && !distances[i].isnull)
902  {
903  scan->xs_orderbyvals[i] = Float4GetDatum((float4) distances[i].value);
904  scan->xs_orderbynulls[i] = false;
905  }
906  else
907  {
908  scan->xs_orderbyvals[i] = (Datum) 0;
909  scan->xs_orderbynulls[i] = true;
910  }
911  }
912  else
913  {
914  /*
915  * If the ordering operator's return value is anything else, we
916  * don't know how to convert the float8 bound calculated by the
917  * distance function to that. The executor won't actually need
918  * the order by values we return here, if there are no lossy
919  * results, so only insist on converting if the *recheck flag is
920  * set.
921  */
922  if (scan->xs_recheckorderby)
923  elog(ERROR, "ORDER BY operator must return float8 or float4 if the distance function is lossy");
924  scan->xs_orderbynulls[i] = true;
925  }
926  }
927 }
928 
929 /* ----------------
930  * index_opclass_options
931  *
932  * Parse opclass-specific options for index column.
933  * ----------------
934  */
935 bytea *
937  bool validate)
938 {
939  int amoptsprocnum = indrel->rd_indam->amoptsprocnum;
940  Oid procid = InvalidOid;
941  FmgrInfo *procinfo;
942  local_relopts relopts;
943 
944  /* fetch options support procedure if specified */
945  if (amoptsprocnum != 0)
946  procid = index_getprocid(indrel, attnum, amoptsprocnum);
947 
948  if (!OidIsValid(procid))
949  {
950  Oid opclass;
951  Datum indclassDatum;
952  oidvector *indclass;
953  bool isnull;
954 
955  if (!DatumGetPointer(attoptions))
956  return NULL; /* ok, no options, no procedure */
957 
958  /*
959  * Report an error if the opclass's options-parsing procedure does not
960  * exist but the opclass options are specified.
961  */
962  indclassDatum = SysCacheGetAttr(INDEXRELID, indrel->rd_indextuple,
963  Anum_pg_index_indclass, &isnull);
964  Assert(!isnull);
965  indclass = (oidvector *) DatumGetPointer(indclassDatum);
966  opclass = indclass->values[attnum - 1];
967 
968  ereport(ERROR,
969  (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
970  errmsg("operator class %s has no options",
971  generate_opclass_name(opclass))));
972  }
973 
974  init_local_reloptions(&relopts, 0);
975 
976  procinfo = index_getprocinfo(indrel, attnum, amoptsprocnum);
977 
978  (void) FunctionCall1(procinfo, PointerGetDatum(&relopts));
979 
980  return build_local_reloptions(&relopts, attoptions, validate);
981 }
static Datum Float4GetDatum(float4 X)
Definition: postgres.h:681
#define ItemPointerIsValid(pointer)
Definition: itemptr.h:82
ambeginscan_function ambeginscan
Definition: amapi.h:227
IndexScanDesc index_beginscan_bitmap(Relation indexRelation, Snapshot snapshot, int nkeys)
Definition: indexam.c:232
Definition: c.h:594
struct IndexAmRoutine * rd_indam
Definition: rel.h:188
Definition: fmgr.h:56
ambulkdelete_function ambulkdelete
Definition: amapi.h:219
LockRelId lockRelId
Definition: rel.h:44
uint16 amsupport
Definition: amapi.h:173
void init_local_reloptions(local_relopts *opts, Size relopt_struct_size)
Definition: reloptions.c:710
Snapshot RestoreSnapshot(char *start_address)
Definition: snapmgr.c:2161
FmgrInfo * index_getprocinfo(Relation irel, AttrNumber attnum, uint16 procnum)
Definition: indexam.c:800
Snapshot RegisterSnapshot(Snapshot snapshot)
Definition: snapmgr.c:865
amgettuple_function amgettuple
Definition: amapi.h:229
struct FmgrInfo * rd_supportinfo
Definition: rel.h:192
int LOCKMODE
Definition: lockdefs.h:26
void UnlockRelationId(LockRelId *relid, LOCKMODE lockmode)
Definition: lmgr.c:184
#define RELATION_CHECKS
Definition: indexam.c:79
IndexScanDesc index_beginscan_parallel(Relation heaprel, Relation indexrel, int nkeys, int norderbys, ParallelIndexScanDesc pscan)
Definition: indexam.c:482
#define PointerGetDatum(X)
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void index_markpos(IndexScanDesc scan)
Definition: indexam.c:351
void PredicateLockRelation(Relation relation, Snapshot snapshot)
Definition: predicate.c:2500
void * build_local_reloptions(local_relopts *relopts, Datum options, bool validate)
Definition: reloptions.c:1924
regproc RegProcedure
Definition: c.h:511
amparallelrescan_function amparallelrescan
Definition: amapi.h:238
static MemoryContext MemoryContextSwitchTo(MemoryContext context)
Definition: palloc.h:109
void index_rescan(IndexScanDesc scan, ScanKey keys, int nkeys, ScanKey orderbys, int norderbys)
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static IndexFetchTableData * table_index_fetch_begin(Relation rel)
Definition: tableam.h:965
int errcode(int sqlerrcode)
Definition: elog.c:610
Datum * xs_orderbyvals
Definition: relscan.h:146
Relation index
Definition: genam.h:46
bool xs_recheckorderby
Definition: relscan.h:148
bool ampredlocks
Definition: amapi.h:197
struct SnapshotData * xs_snapshot
Definition: relscan.h:104
void set_fn_opclass_options(FmgrInfo *flinfo, bytea *options)
Definition: fmgr.c:1964
char ps_snapshot_data[FLEXIBLE_ARRAY_MEMBER]
Definition: relscan.h:160
aminsert_function aminsert
Definition: amapi.h:218
Form_pg_class rd_rel
Definition: rel.h:109
unsigned int Oid
Definition: postgres_ext.h:31
#define OidIsValid(objectId)
Definition: c.h:644
#define CHECK_SCAN_PROCEDURE(pname)
Definition: indexam.c:100
Datum Float8GetDatum(float8 X)
Definition: fmgr.c:1710
Relation indexRelation
Definition: relscan.h:103
#define CHECK_REL_PROCEDURE(pname)
Definition: indexam.c:93
struct HeapTupleData * rd_indextuple
Definition: rel.h:176
Size index_parallelscan_estimate(Relation indexRelation, Snapshot snapshot)
Definition: indexam.c:400
void index_parallelrescan(IndexScanDesc scan)
Definition: indexam.c:464
Relation heapRelation
Definition: relscan.h:102
IndexUniqueCheck
Definition: genam.h:112
void index_restrpos(IndexScanDesc scan)
Definition: indexam.c:375
bool index_can_return(Relation indexRelation, int attno)
Definition: indexam.c:728
bool * xs_orderbynulls
Definition: relscan.h:147
ItemPointer index_getnext_tid(IndexScanDesc scan, ScanDirection direction)
Definition: indexam.c:515
unsigned short uint16
Definition: c.h:366
void pfree(void *pointer)
Definition: mcxt.c:1056
void RelationDecrementReferenceCount(Relation rel)
Definition: relcache.c:2083
amgetbitmap_function amgetbitmap
Definition: amapi.h:230
#define ERROR
Definition: elog.h:43
Definition: rel.h:36
void SerializeSnapshot(Snapshot snapshot, char *start_address)
Definition: snapmgr.c:2102
Relation relation_open(Oid relationId, LOCKMODE lockmode)
Definition: relation.c:48
static void callback(struct sockaddr *addr, struct sockaddr *mask, void *unused)
Definition: test_ifaddrs.c:48
#define pgstat_count_heap_fetch(rel)
Definition: pgstat.h:1407
ItemPointerData xs_heaptid
Definition: relscan.h:132
#define NoLock
Definition: lockdefs.h:34
LockInfoData rd_lockInfo
Definition: rel.h:112
amvacuumcleanup_function amvacuumcleanup
Definition: amapi.h:220
amendscan_function amendscan
Definition: amapi.h:231
bool xactStartedInRecovery
Definition: relscan.h:115
Oid values[FLEXIBLE_ARRAY_MEMBER]
Definition: c.h:602
TransactionId RecentGlobalXmin
Definition: snapmgr.c:168
#define RegProcedureIsValid(p)
Definition: c.h:646
ScanDirection
Definition: sdir.h:22
#define RelationGetRelationName(relation)
Definition: rel.h:490
void IndexScanEnd(IndexScanDesc scan)
Definition: genam.c:144
void RelationClose(Relation relation)
Definition: relcache.c:2103
void fmgr_info_cxt(Oid functionId, FmgrInfo *finfo, MemoryContext mcxt)
Definition: fmgr.c:136
#define OffsetToPointer(base, offset)
Definition: c.h:641
void index_endscan(IndexScanDesc scan)
Definition: indexam.c:321
amrescan_function amrescan
Definition: amapi.h:228
RegProcedure * rd_support
Definition: rel.h:191
int64 index_getbitmap(IndexScanDesc scan, TIDBitmap *bitmap)
Definition: indexam.c:658
bytea * index_opclass_options(Relation indrel, AttrNumber attnum, Datum attoptions, bool validate)
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Definition: snapmgr.c:907
float float4
Definition: c.h:490
char * generate_opclass_name(Oid opclass)
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Size EstimateSnapshotSpace(Snapshot snap)
Definition: snapmgr.c:2078
#define MAX_LOCKMODES
Definition: lock.h:84
struct ParallelIndexScanDescData * parallel_scan
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Definition: indexam.c:868
IndexBulkDeleteResult * index_bulk_delete(IndexVacuumInfo *info, IndexBulkDeleteResult *stats, IndexBulkDeleteCallback callback, void *callback_state)
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uintptr_t Datum
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Size add_size(Size s1, Size s2)
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Datum SysCacheGetAttr(int cacheId, HeapTuple tup, AttrNumber attributeNumber, bool *isNull)
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static bool table_index_fetch_tuple(struct IndexFetchTableData *scan, ItemPointer tid, Snapshot snapshot, TupleTableSlot *slot, bool *call_again, bool *all_dead)
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#define IsMVCCSnapshot(snapshot)
Definition: snapmgr.h:97
#define InvalidOid
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int16 attnum
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static struct @143 value
Oid fn_oid
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#define ereport(elevel,...)
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static void table_index_fetch_reset(struct IndexFetchTableData *scan)
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static IndexScanDesc index_beginscan_internal(Relation indexRelation, int nkeys, int norderbys, Snapshot snapshot, ParallelIndexScanDesc pscan, bool temp_snap)
Definition: indexam.c:253
#define Assert(condition)
Definition: c.h:738
IndexFetchTableData * xs_heapfetch
Definition: relscan.h:135
size_t Size
Definition: c.h:466
#define SCAN_CHECKS
Definition: indexam.c:86
#define InvalidBlockNumber
Definition: block.h:33
bool index_getnext_slot(IndexScanDesc scan, ScanDirection direction, TupleTableSlot *slot)
Definition: indexam.c:613
#define MAXALIGN(LEN)
Definition: c.h:691
bool xs_heap_continue
Definition: relscan.h:133
ammarkpos_function ammarkpos
Definition: amapi.h:232
#define pgstat_count_index_tuples(rel, n)
Definition: pgstat.h:1417
IndexBulkDeleteResult * index_vacuum_cleanup(IndexVacuumInfo *info, IndexBulkDeleteResult *stats)
Definition: indexam.c:709
amestimateparallelscan_function amestimateparallelscan
Definition: amapi.h:236
bool ItemPointerEquals(ItemPointer pointer1, ItemPointer pointer2)
Definition: itemptr.c:29
void index_close(Relation relation, LOCKMODE lockmode)
Definition: indexam.c:158
#define DatumGetPointer(X)
Definition: postgres.h:549
static Datum values[MAXATTR]
Definition: bootstrap.c:167
int errmsg(const char *fmt,...)
Definition: elog.c:824
uint16 amoptsprocnum
Definition: amapi.h:175
void index_parallelscan_initialize(Relation heapRelation, Relation indexRelation, Snapshot snapshot, ParallelIndexScanDesc target)
Definition: indexam.c:433
#define elog(elevel,...)
Definition: elog.h:214
MemoryContext rd_indexcxt
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int i
bool kill_prior_tuple
Definition: relscan.h:113
#define FunctionCall1(flinfo, arg1)
Definition: fmgr.h:642
bool index_fetch_heap(IndexScanDesc scan, TupleTableSlot *slot)
Definition: indexam.c:572
Definition: c.h:555
int numberOfOrderBys
Definition: relscan.h:106
bytea ** RelationGetIndexAttOptions(Relation relation, bool copy)
Definition: relcache.c:5429
#define TransactionIdIsValid(xid)
Definition: transam.h:41
static void table_index_fetch_end(struct IndexFetchTableData *scan)
Definition: tableam.h:984
amcanreturn_function amcanreturn
Definition: amapi.h:221
int16 AttrNumber
Definition: attnum.h:21
#define RelationGetRelid(relation)
Definition: rel.h:456
Relation index_open(Oid relationId, LOCKMODE lockmode)
Definition: indexam.c:132
#define offsetof(type, field)
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bool(* IndexBulkDeleteCallback)(ItemPointer itemptr, void *state)
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aminitparallelscan_function aminitparallelscan
Definition: amapi.h:237
bool index_insert(Relation indexRelation, Datum *values, bool *isnull, ItemPointer heap_t_ctid, Relation heapRelation, IndexUniqueCheck checkUnique, IndexInfo *indexInfo)
Definition: indexam.c:176
IndexScanDesc index_beginscan(Relation heapRelation, Relation indexRelation, Snapshot snapshot, int nkeys, int norderbys)
Definition: indexam.c:203
amrestrpos_function amrestrpos
Definition: amapi.h:233
RegProcedure index_getprocid(Relation irel, AttrNumber attnum, uint16 procnum)
Definition: indexam.c:766