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genam.c
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1 /*-------------------------------------------------------------------------
2  *
3  * genam.c
4  * general index access method routines
5  *
6  * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
7  * Portions Copyright (c) 1994, Regents of the University of California
8  *
9  *
10  * IDENTIFICATION
11  * src/backend/access/index/genam.c
12  *
13  * NOTES
14  * many of the old access method routines have been turned into
15  * macros and moved to genam.h -cim 4/30/91
16  *
17  *-------------------------------------------------------------------------
18  */
19 
20 #include "postgres.h"
21 
22 #include "access/relscan.h"
23 #include "access/transam.h"
24 #include "catalog/index.h"
25 #include "lib/stringinfo.h"
26 #include "miscadmin.h"
27 #include "storage/bufmgr.h"
28 #include "utils/acl.h"
29 #include "utils/builtins.h"
30 #include "utils/lsyscache.h"
31 #include "utils/rel.h"
32 #include "utils/rls.h"
33 #include "utils/ruleutils.h"
34 #include "utils/snapmgr.h"
35 #include "utils/syscache.h"
36 #include "utils/tqual.h"
37 
38 
39 /* ----------------------------------------------------------------
40  * general access method routines
41  *
42  * All indexed access methods use an identical scan structure.
43  * We don't know how the various AMs do locking, however, so we don't
44  * do anything about that here.
45  *
46  * The intent is that an AM implementor will define a beginscan routine
47  * that calls RelationGetIndexScan, to fill in the scan, and then does
48  * whatever kind of locking he wants.
49  *
50  * At the end of a scan, the AM's endscan routine undoes the locking,
51  * but does *not* call IndexScanEnd --- the higher-level index_endscan
52  * routine does that. (We can't do it in the AM because index_endscan
53  * still needs to touch the IndexScanDesc after calling the AM.)
54  *
55  * Because of this, the AM does not have a choice whether to call
56  * RelationGetIndexScan or not; its beginscan routine must return an
57  * object made by RelationGetIndexScan. This is kinda ugly but not
58  * worth cleaning up now.
59  * ----------------------------------------------------------------
60  */
61 
62 /* ----------------
63  * RelationGetIndexScan -- Create and fill an IndexScanDesc.
64  *
65  * This routine creates an index scan structure and sets up initial
66  * contents for it.
67  *
68  * Parameters:
69  * indexRelation -- index relation for scan.
70  * nkeys -- count of scan keys (index qual conditions).
71  * norderbys -- count of index order-by operators.
72  *
73  * Returns:
74  * An initialized IndexScanDesc.
75  * ----------------
76  */
78 RelationGetIndexScan(Relation indexRelation, int nkeys, int norderbys)
79 {
80  IndexScanDesc scan;
81 
82  scan = (IndexScanDesc) palloc(sizeof(IndexScanDescData));
83 
84  scan->heapRelation = NULL; /* may be set later */
85  scan->indexRelation = indexRelation;
86  scan->xs_snapshot = InvalidSnapshot; /* caller must initialize this */
87  scan->numberOfKeys = nkeys;
88  scan->numberOfOrderBys = norderbys;
89 
90  /*
91  * We allocate key workspace here, but it won't get filled until amrescan.
92  */
93  if (nkeys > 0)
94  scan->keyData = (ScanKey) palloc(sizeof(ScanKeyData) * nkeys);
95  else
96  scan->keyData = NULL;
97  if (norderbys > 0)
98  scan->orderByData = (ScanKey) palloc(sizeof(ScanKeyData) * norderbys);
99  else
100  scan->orderByData = NULL;
101 
102  scan->xs_want_itup = false; /* may be set later */
103 
104  /*
105  * During recovery we ignore killed tuples and don't bother to kill them
106  * either. We do this because the xmin on the primary node could easily be
107  * later than the xmin on the standby node, so that what the primary
108  * thinks is killed is supposed to be visible on standby. So for correct
109  * MVCC for queries during recovery we must ignore these hints and check
110  * all tuples. Do *not* set ignore_killed_tuples to true when running in a
111  * transaction that was started during recovery. xactStartedInRecovery
112  * should not be altered by index AMs.
113  */
114  scan->kill_prior_tuple = false;
117 
118  scan->opaque = NULL;
119 
120  scan->xs_itup = NULL;
121  scan->xs_itupdesc = NULL;
122 
124  scan->xs_ctup.t_data = NULL;
125  scan->xs_cbuf = InvalidBuffer;
126  scan->xs_continue_hot = false;
127 
128  return scan;
129 }
130 
131 /* ----------------
132  * IndexScanEnd -- End an index scan.
133  *
134  * This routine just releases the storage acquired by
135  * RelationGetIndexScan(). Any AM-level resources are
136  * assumed to already have been released by the AM's
137  * endscan routine.
138  *
139  * Returns:
140  * None.
141  * ----------------
142  */
143 void
145 {
146  if (scan->keyData != NULL)
147  pfree(scan->keyData);
148  if (scan->orderByData != NULL)
149  pfree(scan->orderByData);
150 
151  pfree(scan);
152 }
153 
154 /*
155  * BuildIndexValueDescription
156  *
157  * Construct a string describing the contents of an index entry, in the
158  * form "(key_name, ...)=(key_value, ...)". This is currently used
159  * for building unique-constraint and exclusion-constraint error messages.
160  *
161  * Note that if the user does not have permissions to view all of the
162  * columns involved then a NULL is returned. Returning a partial key seems
163  * unlikely to be useful and we have no way to know which of the columns the
164  * user provided (unlike in ExecBuildSlotValueDescription).
165  *
166  * The passed-in values/nulls arrays are the "raw" input to the index AM,
167  * e.g. results of FormIndexDatum --- this is not necessarily what is stored
168  * in the index, but it's what the user perceives to be stored.
169  */
170 char *
172  Datum *values, bool *isnull)
173 {
175  Form_pg_index idxrec;
176  HeapTuple ht_idx;
177  int natts = indexRelation->rd_rel->relnatts;
178  int i;
179  int keyno;
180  Oid indexrelid = RelationGetRelid(indexRelation);
181  Oid indrelid;
182  AclResult aclresult;
183 
184  /*
185  * Check permissions- if the user does not have access to view all of the
186  * key columns then return NULL to avoid leaking data.
187  *
188  * First check if RLS is enabled for the relation. If so, return NULL to
189  * avoid leaking data.
190  *
191  * Next we need to check table-level SELECT access and then, if there is
192  * no access there, check column-level permissions.
193  */
194 
195  /*
196  * Fetch the pg_index tuple by the Oid of the index
197  */
198  ht_idx = SearchSysCache1(INDEXRELID, ObjectIdGetDatum(indexrelid));
199  if (!HeapTupleIsValid(ht_idx))
200  elog(ERROR, "cache lookup failed for index %u", indexrelid);
201  idxrec = (Form_pg_index) GETSTRUCT(ht_idx);
202 
203  indrelid = idxrec->indrelid;
204  Assert(indexrelid == idxrec->indexrelid);
205 
206  /* RLS check- if RLS is enabled then we don't return anything. */
207  if (check_enable_rls(indrelid, InvalidOid, true) == RLS_ENABLED)
208  {
209  ReleaseSysCache(ht_idx);
210  return NULL;
211  }
212 
213  /* Table-level SELECT is enough, if the user has it */
214  aclresult = pg_class_aclcheck(indrelid, GetUserId(), ACL_SELECT);
215  if (aclresult != ACLCHECK_OK)
216  {
217  /*
218  * No table-level access, so step through the columns in the index and
219  * make sure the user has SELECT rights on all of them.
220  */
221  for (keyno = 0; keyno < idxrec->indnatts; keyno++)
222  {
223  AttrNumber attnum = idxrec->indkey.values[keyno];
224 
225  /*
226  * Note that if attnum == InvalidAttrNumber, then this is an index
227  * based on an expression and we return no detail rather than try
228  * to figure out what column(s) the expression includes and if the
229  * user has SELECT rights on them.
230  */
231  if (attnum == InvalidAttrNumber ||
232  pg_attribute_aclcheck(indrelid, attnum, GetUserId(),
234  {
235  /* No access, so clean up and return */
236  ReleaseSysCache(ht_idx);
237  return NULL;
238  }
239  }
240  }
241  ReleaseSysCache(ht_idx);
242 
243  initStringInfo(&buf);
244  appendStringInfo(&buf, "(%s)=(",
245  pg_get_indexdef_columns(indexrelid, true));
246 
247  for (i = 0; i < natts; i++)
248  {
249  char *val;
250 
251  if (isnull[i])
252  val = "null";
253  else
254  {
255  Oid foutoid;
256  bool typisvarlena;
257 
258  /*
259  * The provided data is not necessarily of the type stored in the
260  * index; rather it is of the index opclass's input type. So look
261  * at rd_opcintype not the index tupdesc.
262  *
263  * Note: this is a bit shaky for opclasses that have pseudotype
264  * input types such as ANYARRAY or RECORD. Currently, the
265  * typoutput functions associated with the pseudotypes will work
266  * okay, but we might have to try harder in future.
267  */
268  getTypeOutputInfo(indexRelation->rd_opcintype[i],
269  &foutoid, &typisvarlena);
270  val = OidOutputFunctionCall(foutoid, values[i]);
271  }
272 
273  if (i > 0)
274  appendStringInfoString(&buf, ", ");
275  appendStringInfoString(&buf, val);
276  }
277 
278  appendStringInfoChar(&buf, ')');
279 
280  return buf.data;
281 }
282 
283 
284 /* ----------------------------------------------------------------
285  * heap-or-index-scan access to system catalogs
286  *
287  * These functions support system catalog accesses that normally use
288  * an index but need to be capable of being switched to heap scans
289  * if the system indexes are unavailable.
290  *
291  * The specified scan keys must be compatible with the named index.
292  * Generally this means that they must constrain either all columns
293  * of the index, or the first K columns of an N-column index.
294  *
295  * These routines could work with non-system tables, actually,
296  * but they're only useful when there is a known index to use with
297  * the given scan keys; so in practice they're only good for
298  * predetermined types of scans of system catalogs.
299  * ----------------------------------------------------------------
300  */
301 
302 /*
303  * systable_beginscan --- set up for heap-or-index scan
304  *
305  * rel: catalog to scan, already opened and suitably locked
306  * indexId: OID of index to conditionally use
307  * indexOK: if false, forces a heap scan (see notes below)
308  * snapshot: time qual to use (NULL for a recent catalog snapshot)
309  * nkeys, key: scan keys
310  *
311  * The attribute numbers in the scan key should be set for the heap case.
312  * If we choose to index, we reset them to 1..n to reference the index
313  * columns. Note this means there must be one scankey qualification per
314  * index column! This is checked by the Asserts in the normal, index-using
315  * case, but won't be checked if the heapscan path is taken.
316  *
317  * The routine checks the normal cases for whether an indexscan is safe,
318  * but caller can make additional checks and pass indexOK=false if needed.
319  * In standard case indexOK can simply be constant TRUE.
320  */
323  Oid indexId,
324  bool indexOK,
325  Snapshot snapshot,
326  int nkeys, ScanKey key)
327 {
328  SysScanDesc sysscan;
329  Relation irel;
330 
331  if (indexOK &&
333  !ReindexIsProcessingIndex(indexId))
334  irel = index_open(indexId, AccessShareLock);
335  else
336  irel = NULL;
337 
338  sysscan = (SysScanDesc) palloc(sizeof(SysScanDescData));
339 
340  sysscan->heap_rel = heapRelation;
341  sysscan->irel = irel;
342 
343  if (snapshot == NULL)
344  {
345  Oid relid = RelationGetRelid(heapRelation);
346 
347  snapshot = RegisterSnapshot(GetCatalogSnapshot(relid));
348  sysscan->snapshot = snapshot;
349  }
350  else
351  {
352  /* Caller is responsible for any snapshot. */
353  sysscan->snapshot = NULL;
354  }
355 
356  if (irel)
357  {
358  int i;
359 
360  /* Change attribute numbers to be index column numbers. */
361  for (i = 0; i < nkeys; i++)
362  {
363  int j;
364 
365  for (j = 0; j < irel->rd_index->indnatts; j++)
366  {
367  if (key[i].sk_attno == irel->rd_index->indkey.values[j])
368  {
369  key[i].sk_attno = j + 1;
370  break;
371  }
372  }
373  if (j == irel->rd_index->indnatts)
374  elog(ERROR, "column is not in index");
375  }
376 
377  sysscan->iscan = index_beginscan(heapRelation, irel,
378  snapshot, nkeys, 0);
379  index_rescan(sysscan->iscan, key, nkeys, NULL, 0);
380  sysscan->scan = NULL;
381  }
382  else
383  {
384  /*
385  * We disallow synchronized scans when forced to use a heapscan on a
386  * catalog. In most cases the desired rows are near the front, so
387  * that the unpredictable start point of a syncscan is a serious
388  * disadvantage; and there are no compensating advantages, because
389  * it's unlikely that such scans will occur in parallel.
390  */
391  sysscan->scan = heap_beginscan_strat(heapRelation, snapshot,
392  nkeys, key,
393  true, false);
394  sysscan->iscan = NULL;
395  }
396 
397  return sysscan;
398 }
399 
400 /*
401  * systable_getnext --- get next tuple in a heap-or-index scan
402  *
403  * Returns NULL if no more tuples available.
404  *
405  * Note that returned tuple is a reference to data in a disk buffer;
406  * it must not be modified, and should be presumed inaccessible after
407  * next getnext() or endscan() call.
408  */
409 HeapTuple
411 {
412  HeapTuple htup;
413 
414  if (sysscan->irel)
415  {
416  htup = index_getnext(sysscan->iscan, ForwardScanDirection);
417 
418  /*
419  * We currently don't need to support lossy index operators for any
420  * system catalog scan. It could be done here, using the scan keys to
421  * drive the operator calls, if we arranged to save the heap attnums
422  * during systable_beginscan(); this is practical because we still
423  * wouldn't need to support indexes on expressions.
424  */
425  if (htup && sysscan->iscan->xs_recheck)
426  elog(ERROR, "system catalog scans with lossy index conditions are not implemented");
427  }
428  else
429  htup = heap_getnext(sysscan->scan, ForwardScanDirection);
430 
431  return htup;
432 }
433 
434 /*
435  * systable_recheck_tuple --- recheck visibility of most-recently-fetched tuple
436  *
437  * In particular, determine if this tuple would be visible to a catalog scan
438  * that started now. We don't handle the case of a non-MVCC scan snapshot,
439  * because no caller needs that yet.
440  *
441  * This is useful to test whether an object was deleted while we waited to
442  * acquire lock on it.
443  *
444  * Note: we don't actually *need* the tuple to be passed in, but it's a
445  * good crosscheck that the caller is interested in the right tuple.
446  */
447 bool
449 {
450  Snapshot freshsnap;
451  bool result;
452 
453  /*
454  * Trust that LockBuffer() and HeapTupleSatisfiesMVCC() do not themselves
455  * acquire snapshots, so we need not register the snapshot. Those
456  * facilities are too low-level to have any business scanning tables.
457  */
458  freshsnap = GetCatalogSnapshot(RelationGetRelid(sysscan->heap_rel));
459 
460  if (sysscan->irel)
461  {
462  IndexScanDesc scan = sysscan->iscan;
463 
465  Assert(tup == &scan->xs_ctup);
466  Assert(BufferIsValid(scan->xs_cbuf));
467  /* must hold a buffer lock to call HeapTupleSatisfiesVisibility */
469  result = HeapTupleSatisfiesVisibility(tup, freshsnap, scan->xs_cbuf);
471  }
472  else
473  {
474  HeapScanDesc scan = sysscan->scan;
475 
477  Assert(tup == &scan->rs_ctup);
478  Assert(BufferIsValid(scan->rs_cbuf));
479  /* must hold a buffer lock to call HeapTupleSatisfiesVisibility */
481  result = HeapTupleSatisfiesVisibility(tup, freshsnap, scan->rs_cbuf);
483  }
484  return result;
485 }
486 
487 /*
488  * systable_endscan --- close scan, release resources
489  *
490  * Note that it's still up to the caller to close the heap relation.
491  */
492 void
494 {
495  if (sysscan->irel)
496  {
497  index_endscan(sysscan->iscan);
498  index_close(sysscan->irel, AccessShareLock);
499  }
500  else
501  heap_endscan(sysscan->scan);
502 
503  if (sysscan->snapshot)
504  UnregisterSnapshot(sysscan->snapshot);
505 
506  pfree(sysscan);
507 }
508 
509 
510 /*
511  * systable_beginscan_ordered --- set up for ordered catalog scan
512  *
513  * These routines have essentially the same API as systable_beginscan etc,
514  * except that they guarantee to return multiple matching tuples in
515  * index order. Also, for largely historical reasons, the index to use
516  * is opened and locked by the caller, not here.
517  *
518  * Currently we do not support non-index-based scans here. (In principle
519  * we could do a heapscan and sort, but the uses are in places that
520  * probably don't need to still work with corrupted catalog indexes.)
521  * For the moment, therefore, these functions are merely the thinnest of
522  * wrappers around index_beginscan/index_getnext. The main reason for their
523  * existence is to centralize possible future support of lossy operators
524  * in catalog scans.
525  */
528  Relation indexRelation,
529  Snapshot snapshot,
530  int nkeys, ScanKey key)
531 {
532  SysScanDesc sysscan;
533  int i;
534 
535  /* REINDEX can probably be a hard error here ... */
536  if (ReindexIsProcessingIndex(RelationGetRelid(indexRelation)))
537  elog(ERROR, "cannot do ordered scan on index \"%s\", because it is being reindexed",
538  RelationGetRelationName(indexRelation));
539  /* ... but we only throw a warning about violating IgnoreSystemIndexes */
541  elog(WARNING, "using index \"%s\" despite IgnoreSystemIndexes",
542  RelationGetRelationName(indexRelation));
543 
544  sysscan = (SysScanDesc) palloc(sizeof(SysScanDescData));
545 
546  sysscan->heap_rel = heapRelation;
547  sysscan->irel = indexRelation;
548 
549  if (snapshot == NULL)
550  {
551  Oid relid = RelationGetRelid(heapRelation);
552 
553  snapshot = RegisterSnapshot(GetCatalogSnapshot(relid));
554  sysscan->snapshot = snapshot;
555  }
556  else
557  {
558  /* Caller is responsible for any snapshot. */
559  sysscan->snapshot = NULL;
560  }
561 
562  /* Change attribute numbers to be index column numbers. */
563  for (i = 0; i < nkeys; i++)
564  {
565  int j;
566 
567  for (j = 0; j < indexRelation->rd_index->indnatts; j++)
568  {
569  if (key[i].sk_attno == indexRelation->rd_index->indkey.values[j])
570  {
571  key[i].sk_attno = j + 1;
572  break;
573  }
574  }
575  if (j == indexRelation->rd_index->indnatts)
576  elog(ERROR, "column is not in index");
577  }
578 
579  sysscan->iscan = index_beginscan(heapRelation, indexRelation,
580  snapshot, nkeys, 0);
581  index_rescan(sysscan->iscan, key, nkeys, NULL, 0);
582  sysscan->scan = NULL;
583 
584  return sysscan;
585 }
586 
587 /*
588  * systable_getnext_ordered --- get next tuple in an ordered catalog scan
589  */
590 HeapTuple
592 {
593  HeapTuple htup;
594 
595  Assert(sysscan->irel);
596  htup = index_getnext(sysscan->iscan, direction);
597  /* See notes in systable_getnext */
598  if (htup && sysscan->iscan->xs_recheck)
599  elog(ERROR, "system catalog scans with lossy index conditions are not implemented");
600 
601  return htup;
602 }
603 
604 /*
605  * systable_endscan_ordered --- close scan, release resources
606  */
607 void
609 {
610  Assert(sysscan->irel);
611  index_endscan(sysscan->iscan);
612  if (sysscan->snapshot)
613  UnregisterSnapshot(sysscan->snapshot);
614  pfree(sysscan);
615 }
Relation irel
Definition: relscan.h:148
Snapshot snapshot
Definition: relscan.h:151
#define BUFFER_LOCK_UNLOCK
Definition: bufmgr.h:87
struct SysScanDescData * SysScanDesc
Definition: genam.h:87
void getTypeOutputInfo(Oid type, Oid *typOutput, bool *typIsVarlena)
Definition: lsyscache.c:2600
Relation heap_rel
Definition: relscan.h:147
void systable_endscan(SysScanDesc sysscan)
Definition: genam.c:493
#define GETSTRUCT(TUP)
Definition: htup_details.h:656
void heap_endscan(HeapScanDesc scan)
Definition: heapam.c:1581
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Definition: xact.c:870
IndexTuple xs_itup
Definition: relscan.h:108
Snapshot RegisterSnapshot(Snapshot snapshot)
Definition: snapmgr.c:858
AclResult pg_attribute_aclcheck(Oid table_oid, AttrNumber attnum, Oid roleid, AclMode mode)
Definition: aclchk.c:4283
Oid GetUserId(void)
Definition: miscinit.c:283
Snapshot GetCatalogSnapshot(Oid relid)
Definition: snapmgr.c:436
#define AccessShareLock
Definition: lockdefs.h:36
Snapshot xs_snapshot
Definition: relscan.h:90
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Definition: buf.h:25
char * pg_get_indexdef_columns(Oid indexrelid, bool pretty)
Definition: ruleutils.c:1121
void index_rescan(IndexScanDesc scan, ScanKey keys, int nkeys, ScanKey orderbys, int norderbys)
Definition: indexam.c:310
bool IgnoreSystemIndexes
Definition: miscinit.c:73
TupleDesc xs_itupdesc
Definition: relscan.h:109
HeapTuple systable_getnext_ordered(SysScanDesc sysscan, ScanDirection direction)
Definition: genam.c:591
Form_pg_class rd_rel
Definition: rel.h:113
unsigned int Oid
Definition: postgres_ext.h:31
SysScanDesc systable_beginscan(Relation heapRelation, Oid indexId, bool indexOK, Snapshot snapshot, int nkeys, ScanKey key)
Definition: genam.c:322
IndexScanDesc iscan
Definition: relscan.h:150
bool ignore_killed_tuples
Definition: relscan.h:100
#define SearchSysCache1(cacheId, key1)
Definition: syscache.h:149
#define HeapTupleSatisfiesVisibility(tuple, snapshot, buffer)
Definition: tqual.h:45
Relation indexRelation
Definition: relscan.h:89
HeapTupleData rs_ctup
Definition: relscan.h:68
bool systable_recheck_tuple(SysScanDesc sysscan, HeapTuple tup)
Definition: genam.c:448
HeapTupleHeader t_data
Definition: htup.h:67
Relation heapRelation
Definition: relscan.h:88
Form_pg_index rd_index
Definition: rel.h:155
HeapTuple systable_getnext(SysScanDesc sysscan)
Definition: genam.c:410
void pfree(void *pointer)
Definition: mcxt.c:992
void appendStringInfo(StringInfo str, const char *fmt,...)
Definition: stringinfo.c:110
Buffer xs_cbuf
Definition: relscan.h:113
#define ObjectIdGetDatum(X)
Definition: postgres.h:515
#define ERROR
Definition: elog.h:43
ItemPointerData t_self
Definition: htup.h:65
void appendStringInfoString(StringInfo str, const char *s)
Definition: stringinfo.c:189
static char * buf
Definition: pg_test_fsync.c:65
bool xactStartedInRecovery
Definition: relscan.h:101
ScanKeyData * ScanKey
Definition: skey.h:75
ScanDirection
Definition: sdir.h:22
bool xs_continue_hot
Definition: relscan.h:129
Snapshot rs_snapshot
Definition: relscan.h:48
#define RelationGetRelationName(relation)
Definition: rel.h:433
void IndexScanEnd(IndexScanDesc scan)
Definition: genam.c:144
void index_endscan(IndexScanDesc scan)
Definition: indexam.c:340
void UnregisterSnapshot(Snapshot snapshot)
Definition: snapmgr.c:900
void appendStringInfoChar(StringInfo str, char ch)
Definition: stringinfo.c:201
void initStringInfo(StringInfo str)
Definition: stringinfo.c:65
#define WARNING
Definition: elog.h:40
FormData_pg_index * Form_pg_index
Definition: pg_index.h:67
#define InvalidSnapshot
Definition: snapshot.h:25
AclResult
Definition: acl.h:170
ScanKey orderByData
Definition: relscan.h:94
uintptr_t Datum
Definition: postgres.h:374
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Definition: syscache.c:1083
#define ACL_SELECT
Definition: parsenodes.h:66
void LockBuffer(Buffer buffer, int mode)
Definition: bufmgr.c:3529
HeapTuple heap_getnext(HeapScanDesc scan, ScanDirection direction)
Definition: heapam.c:1781
void systable_endscan_ordered(SysScanDesc sysscan)
Definition: genam.c:608
#define InvalidOid
Definition: postgres_ext.h:36
HeapScanDesc heap_beginscan_strat(Relation relation, Snapshot snapshot, int nkeys, ScanKey key, bool allow_strat, bool allow_sync)
Definition: heapam.c:1412
bool xs_want_itup
Definition: relscan.h:95
Buffer rs_cbuf
Definition: relscan.h:70
int check_enable_rls(Oid relid, Oid checkAsUser, bool noError)
Definition: rls.c:53
#define HeapTupleIsValid(tuple)
Definition: htup.h:77
#define NULL
Definition: c.h:226
#define Assert(condition)
Definition: c.h:671
#define IsMVCCSnapshot(snapshot)
Definition: tqual.h:31
HeapTupleData xs_ctup
Definition: relscan.h:112
#define BufferIsValid(bufnum)
Definition: bufmgr.h:114
ScanKey keyData
Definition: relscan.h:93
HeapScanDesc scan
Definition: relscan.h:149
#define InvalidAttrNumber
Definition: attnum.h:23
void index_close(Relation relation, LOCKMODE lockmode)
Definition: indexam.c:176
AclResult pg_class_aclcheck(Oid table_oid, Oid roleid, AclMode mode)
Definition: aclchk.c:4397
static Datum values[MAXATTR]
Definition: bootstrap.c:162
#define ItemPointerSetInvalid(pointer)
Definition: itemptr.h:131
char * OidOutputFunctionCall(Oid functionId, Datum val)
Definition: fmgr.c:2006
void * palloc(Size size)
Definition: mcxt.c:891
SysScanDesc systable_beginscan_ordered(Relation heapRelation, Relation indexRelation, Snapshot snapshot, int nkeys, ScanKey key)
Definition: genam.c:527
int i
bool kill_prior_tuple
Definition: relscan.h:99
#define BUFFER_LOCK_SHARE
Definition: bufmgr.h:88
IndexScanDesc RelationGetIndexScan(Relation indexRelation, int nkeys, int norderbys)
Definition: genam.c:78
int numberOfOrderBys
Definition: relscan.h:92
#define elog
Definition: elog.h:219
char * BuildIndexValueDescription(Relation indexRelation, Datum *values, bool *isnull)
Definition: genam.c:171
Oid * rd_opcintype
Definition: rel.h:179
bool ReindexIsProcessingIndex(Oid indexOid)
Definition: index.c:3687
struct IndexScanDescData * IndexScanDesc
Definition: genam.h:86
int16 AttrNumber
Definition: attnum.h:21
#define RelationGetRelid(relation)
Definition: rel.h:413
long val
Definition: informix.c:689
Relation index_open(Oid relationId, LOCKMODE lockmode)
Definition: indexam.c:151
HeapTuple index_getnext(IndexScanDesc scan, ScanDirection direction)
Definition: indexam.c:659
AttrNumber sk_attno
Definition: skey.h:67
IndexScanDesc index_beginscan(Relation heapRelation, Relation indexRelation, Snapshot snapshot, int nkeys, int norderbys)
Definition: indexam.c:221