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statscmds.c
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1/*-------------------------------------------------------------------------
2 *
3 * statscmds.c
4 * Commands for creating and altering extended statistics objects
5 *
6 * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
7 * Portions Copyright (c) 1994, Regents of the University of California
8 *
9 *
10 * IDENTIFICATION
11 * src/backend/commands/statscmds.c
12 *
13 *-------------------------------------------------------------------------
14 */
15#include "postgres.h"
16
17#include "access/relation.h"
18#include "access/table.h"
19#include "catalog/catalog.h"
20#include "catalog/dependency.h"
21#include "catalog/indexing.h"
22#include "catalog/namespace.h"
27#include "commands/comment.h"
28#include "commands/defrem.h"
29#include "miscadmin.h"
30#include "nodes/nodeFuncs.h"
31#include "optimizer/optimizer.h"
33#include "utils/acl.h"
34#include "utils/builtins.h"
35#include "utils/inval.h"
36#include "utils/lsyscache.h"
37#include "utils/rel.h"
38#include "utils/syscache.h"
39#include "utils/typcache.h"
40
41
42static char *ChooseExtendedStatisticName(const char *name1, const char *name2,
43 const char *label, Oid namespaceid);
44static char *ChooseExtendedStatisticNameAddition(List *exprs);
45
46
47/* qsort comparator for the attnums in CreateStatistics */
48static int
49compare_int16(const void *a, const void *b)
50{
51 int av = *(const int16 *) a;
52 int bv = *(const int16 *) b;
53
54 /* this can't overflow if int is wider than int16 */
55 return (av - bv);
56}
57
58/*
59 * CREATE STATISTICS
60 */
63{
65 int nattnums = 0;
66 int numcols;
67 char *namestr;
68 NameData stxname;
69 Oid statoid;
70 Oid namespaceId;
71 Oid stxowner = GetUserId();
72 HeapTuple htup;
73 Datum values[Natts_pg_statistic_ext];
74 bool nulls[Natts_pg_statistic_ext];
75 int2vector *stxkeys;
76 List *stxexprs = NIL;
77 Datum exprsDatum;
78 Relation statrel;
79 Relation rel = NULL;
80 Oid relid;
81 ObjectAddress parentobject,
82 myself;
83 Datum types[4]; /* one for each possible type of statistic */
84 int ntypes;
85 ArrayType *stxkind;
86 bool build_ndistinct;
87 bool build_dependencies;
88 bool build_mcv;
89 bool build_expressions;
90 bool requested_type = false;
91 int i;
92 ListCell *cell;
93 ListCell *cell2;
94
96
97 /*
98 * Examine the FROM clause. Currently, we only allow it to be a single
99 * simple table, but later we'll probably allow multiple tables and JOIN
100 * syntax. The grammar is already prepared for that, so we have to check
101 * here that what we got is what we can support.
102 */
103 if (list_length(stmt->relations) != 1)
105 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
106 errmsg("only a single relation is allowed in CREATE STATISTICS")));
107
108 foreach(cell, stmt->relations)
109 {
110 Node *rln = (Node *) lfirst(cell);
111
112 if (!IsA(rln, RangeVar))
114 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
115 errmsg("only a single relation is allowed in CREATE STATISTICS")));
116
117 /*
118 * CREATE STATISTICS will influence future execution plans but does
119 * not interfere with currently executing plans. So it should be
120 * enough to take only ShareUpdateExclusiveLock on relation,
121 * conflicting with ANALYZE and other DDL that sets statistical
122 * information, but not with normal queries.
123 */
125
126 /* Restrict to allowed relation types */
127 if (rel->rd_rel->relkind != RELKIND_RELATION &&
128 rel->rd_rel->relkind != RELKIND_MATVIEW &&
129 rel->rd_rel->relkind != RELKIND_FOREIGN_TABLE &&
130 rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
132 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
133 errmsg("cannot define statistics for relation \"%s\"",
136
137 /* You must own the relation to create stats on it */
138 if (!object_ownercheck(RelationRelationId, RelationGetRelid(rel), stxowner))
141
142 /* Creating statistics on system catalogs is not allowed */
145 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
146 errmsg("permission denied: \"%s\" is a system catalog",
148 }
149
150 Assert(rel);
151 relid = RelationGetRelid(rel);
152
153 /*
154 * If the node has a name, split it up and determine creation namespace.
155 * If not, put the object in the same namespace as the relation, and cons
156 * up a name for it. (This can happen either via "CREATE STATISTICS ..."
157 * or via "CREATE TABLE ... (LIKE)".)
158 */
159 if (stmt->defnames)
160 namespaceId = QualifiedNameGetCreationNamespace(stmt->defnames,
161 &namestr);
162 else
163 {
164 namespaceId = RelationGetNamespace(rel);
167 "stat",
168 namespaceId);
169 }
170 namestrcpy(&stxname, namestr);
171
172 /*
173 * Deal with the possibility that the statistics object already exists.
174 */
175 if (SearchSysCacheExists2(STATEXTNAMENSP,
176 CStringGetDatum(namestr),
177 ObjectIdGetDatum(namespaceId)))
178 {
179 if (stmt->if_not_exists)
180 {
181 /*
182 * Since stats objects aren't members of extensions (see comments
183 * below), no need for checkMembershipInCurrentExtension here.
184 */
187 errmsg("statistics object \"%s\" already exists, skipping",
188 namestr)));
191 }
192
195 errmsg("statistics object \"%s\" already exists", namestr)));
196 }
197
198 /*
199 * Make sure no more than STATS_MAX_DIMENSIONS columns are used. There
200 * might be duplicates and so on, but we'll deal with those later.
201 */
202 numcols = list_length(stmt->exprs);
203 if (numcols > STATS_MAX_DIMENSIONS)
205 (errcode(ERRCODE_TOO_MANY_COLUMNS),
206 errmsg("cannot have more than %d columns in statistics",
208
209 /*
210 * Convert the expression list to a simple array of attnums, but also keep
211 * a list of more complex expressions. While at it, enforce some
212 * constraints - we don't allow extended statistics on system attributes,
213 * and we require the data type to have a less-than operator.
214 *
215 * There are many ways to "mask" a simple attribute reference as an
216 * expression, for example "(a+0)" etc. We can't possibly detect all of
217 * them, but we handle at least the simple case with the attribute in
218 * parens. There'll always be a way around this, if the user is determined
219 * (like the "(a+0)" example), but this makes it somewhat consistent with
220 * how indexes treat attributes/expressions.
221 */
222 foreach(cell, stmt->exprs)
223 {
224 StatsElem *selem = lfirst_node(StatsElem, cell);
225
226 if (selem->name) /* column reference */
227 {
228 char *attname;
229 HeapTuple atttuple;
230 Form_pg_attribute attForm;
232
233 attname = selem->name;
234
235 atttuple = SearchSysCacheAttName(relid, attname);
236 if (!HeapTupleIsValid(atttuple))
238 (errcode(ERRCODE_UNDEFINED_COLUMN),
239 errmsg("column \"%s\" does not exist",
240 attname)));
241 attForm = (Form_pg_attribute) GETSTRUCT(atttuple);
242
243 /* Disallow use of system attributes in extended stats */
244 if (attForm->attnum <= 0)
246 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
247 errmsg("statistics creation on system columns is not supported")));
248
249 /* Disallow use of virtual generated columns in extended stats */
250 if (attForm->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL)
252 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
253 errmsg("statistics creation on virtual generated columns is not supported")));
254
255 /* Disallow data types without a less-than operator */
256 type = lookup_type_cache(attForm->atttypid, TYPECACHE_LT_OPR);
257 if (type->lt_opr == InvalidOid)
259 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
260 errmsg("column \"%s\" cannot be used in statistics because its type %s has no default btree operator class",
261 attname, format_type_be(attForm->atttypid))));
262
263 attnums[nattnums] = attForm->attnum;
264 nattnums++;
265 ReleaseSysCache(atttuple);
266 }
267 else if (IsA(selem->expr, Var)) /* column reference in parens */
268 {
269 Var *var = (Var *) selem->expr;
271
272 /* Disallow use of system attributes in extended stats */
273 if (var->varattno <= 0)
275 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
276 errmsg("statistics creation on system columns is not supported")));
277
278 /* Disallow use of virtual generated columns in extended stats */
279 if (get_attgenerated(relid, var->varattno) == ATTRIBUTE_GENERATED_VIRTUAL)
281 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
282 errmsg("statistics creation on virtual generated columns is not supported")));
283
284 /* Disallow data types without a less-than operator */
285 type = lookup_type_cache(var->vartype, TYPECACHE_LT_OPR);
286 if (type->lt_opr == InvalidOid)
288 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
289 errmsg("column \"%s\" cannot be used in statistics because its type %s has no default btree operator class",
290 get_attname(relid, var->varattno, false), format_type_be(var->vartype))));
291
292 attnums[nattnums] = var->varattno;
293 nattnums++;
294 }
295 else /* expression */
296 {
297 Node *expr = selem->expr;
298 Oid atttype;
300 Bitmapset *attnums = NULL;
301 int k;
302
303 Assert(expr != NULL);
304
305 pull_varattnos(expr, 1, &attnums);
306
307 k = -1;
308 while ((k = bms_next_member(attnums, k)) >= 0)
309 {
311
312 /* Disallow expressions referencing system attributes. */
313 if (attnum <= 0)
315 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
316 errmsg("statistics creation on system columns is not supported")));
317
318 /* Disallow use of virtual generated columns in extended stats */
319 if (get_attgenerated(relid, attnum) == ATTRIBUTE_GENERATED_VIRTUAL)
321 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
322 errmsg("statistics creation on virtual generated columns is not supported")));
323 }
324
325 /*
326 * Disallow data types without a less-than operator.
327 *
328 * We ignore this for statistics on a single expression, in which
329 * case we'll build the regular statistics only (and that code can
330 * deal with such data types).
331 */
332 if (list_length(stmt->exprs) > 1)
333 {
334 atttype = exprType(expr);
336 if (type->lt_opr == InvalidOid)
338 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
339 errmsg("expression cannot be used in multivariate statistics because its type %s has no default btree operator class",
340 format_type_be(atttype))));
341 }
342
343 stxexprs = lappend(stxexprs, expr);
344 }
345 }
346
347 /*
348 * Parse the statistics kinds.
349 *
350 * First check that if this is the case with a single expression, there
351 * are no statistics kinds specified (we don't allow that for the simple
352 * CREATE STATISTICS form).
353 */
354 if ((list_length(stmt->exprs) == 1) && (list_length(stxexprs) == 1))
355 {
356 /* statistics kinds not specified */
357 if (stmt->stat_types != NIL)
359 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
360 errmsg("when building statistics on a single expression, statistics kinds may not be specified")));
361 }
362
363 /* OK, let's check that we recognize the statistics kinds. */
364 build_ndistinct = false;
365 build_dependencies = false;
366 build_mcv = false;
367 foreach(cell, stmt->stat_types)
368 {
369 char *type = strVal(lfirst(cell));
370
371 if (strcmp(type, "ndistinct") == 0)
372 {
373 build_ndistinct = true;
374 requested_type = true;
375 }
376 else if (strcmp(type, "dependencies") == 0)
377 {
378 build_dependencies = true;
379 requested_type = true;
380 }
381 else if (strcmp(type, "mcv") == 0)
382 {
383 build_mcv = true;
384 requested_type = true;
385 }
386 else
388 (errcode(ERRCODE_SYNTAX_ERROR),
389 errmsg("unrecognized statistics kind \"%s\"",
390 type)));
391 }
392
393 /*
394 * If no statistic type was specified, build them all (but only when the
395 * statistics is defined on more than one column/expression).
396 */
397 if ((!requested_type) && (numcols >= 2))
398 {
399 build_ndistinct = true;
400 build_dependencies = true;
401 build_mcv = true;
402 }
403
404 /*
405 * When there are non-trivial expressions, build the expression stats
406 * automatically. This allows calculating good estimates for stats that
407 * consider per-clause estimates (e.g. functional dependencies).
408 */
409 build_expressions = (stxexprs != NIL);
410
411 /*
412 * Check that at least two columns were specified in the statement, or
413 * that we're building statistics on a single expression.
414 */
415 if ((numcols < 2) && (list_length(stxexprs) != 1))
417 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
418 errmsg("extended statistics require at least 2 columns")));
419
420 /*
421 * Sort the attnums, which makes detecting duplicates somewhat easier, and
422 * it does not hurt (it does not matter for the contents, unlike for
423 * indexes, for example).
424 */
425 qsort(attnums, nattnums, sizeof(int16), compare_int16);
426
427 /*
428 * Check for duplicates in the list of columns. The attnums are sorted so
429 * just check consecutive elements.
430 */
431 for (i = 1; i < nattnums; i++)
432 {
433 if (attnums[i] == attnums[i - 1])
435 (errcode(ERRCODE_DUPLICATE_COLUMN),
436 errmsg("duplicate column name in statistics definition")));
437 }
438
439 /*
440 * Check for duplicate expressions. We do two loops, counting the
441 * occurrences of each expression. This is O(N^2) but we only allow small
442 * number of expressions and it's not executed often.
443 *
444 * XXX We don't cross-check attributes and expressions, because it does
445 * not seem worth it. In principle we could check that expressions don't
446 * contain trivial attribute references like "(a)", but the reasoning is
447 * similar to why we don't bother with extracting columns from
448 * expressions. It's either expensive or very easy to defeat for
449 * determined user, and there's no risk if we allow such statistics (the
450 * statistics is useless, but harmless).
451 */
452 foreach(cell, stxexprs)
453 {
454 Node *expr1 = (Node *) lfirst(cell);
455 int cnt = 0;
456
457 foreach(cell2, stxexprs)
458 {
459 Node *expr2 = (Node *) lfirst(cell2);
460
461 if (equal(expr1, expr2))
462 cnt += 1;
463 }
464
465 /* every expression should find at least itself */
466 Assert(cnt >= 1);
467
468 if (cnt > 1)
470 (errcode(ERRCODE_DUPLICATE_COLUMN),
471 errmsg("duplicate expression in statistics definition")));
472 }
473
474 /* Form an int2vector representation of the sorted column list */
475 stxkeys = buildint2vector(attnums, nattnums);
476
477 /* construct the char array of enabled statistic types */
478 ntypes = 0;
479 if (build_ndistinct)
480 types[ntypes++] = CharGetDatum(STATS_EXT_NDISTINCT);
481 if (build_dependencies)
482 types[ntypes++] = CharGetDatum(STATS_EXT_DEPENDENCIES);
483 if (build_mcv)
484 types[ntypes++] = CharGetDatum(STATS_EXT_MCV);
485 if (build_expressions)
486 types[ntypes++] = CharGetDatum(STATS_EXT_EXPRESSIONS);
487 Assert(ntypes > 0 && ntypes <= lengthof(types));
488 stxkind = construct_array_builtin(types, ntypes, CHAROID);
489
490 /* convert the expressions (if any) to a text datum */
491 if (stxexprs != NIL)
492 {
493 char *exprsString;
494
495 exprsString = nodeToString(stxexprs);
496 exprsDatum = CStringGetTextDatum(exprsString);
497 pfree(exprsString);
498 }
499 else
500 exprsDatum = (Datum) 0;
501
502 statrel = table_open(StatisticExtRelationId, RowExclusiveLock);
503
504 /*
505 * Everything seems fine, so let's build the pg_statistic_ext tuple.
506 */
507 memset(values, 0, sizeof(values));
508 memset(nulls, false, sizeof(nulls));
509
510 statoid = GetNewOidWithIndex(statrel, StatisticExtOidIndexId,
511 Anum_pg_statistic_ext_oid);
512 values[Anum_pg_statistic_ext_oid - 1] = ObjectIdGetDatum(statoid);
513 values[Anum_pg_statistic_ext_stxrelid - 1] = ObjectIdGetDatum(relid);
514 values[Anum_pg_statistic_ext_stxname - 1] = NameGetDatum(&stxname);
515 values[Anum_pg_statistic_ext_stxnamespace - 1] = ObjectIdGetDatum(namespaceId);
516 values[Anum_pg_statistic_ext_stxowner - 1] = ObjectIdGetDatum(stxowner);
517 values[Anum_pg_statistic_ext_stxkeys - 1] = PointerGetDatum(stxkeys);
518 nulls[Anum_pg_statistic_ext_stxstattarget - 1] = true;
519 values[Anum_pg_statistic_ext_stxkind - 1] = PointerGetDatum(stxkind);
520
521 values[Anum_pg_statistic_ext_stxexprs - 1] = exprsDatum;
522 if (exprsDatum == (Datum) 0)
523 nulls[Anum_pg_statistic_ext_stxexprs - 1] = true;
524
525 /* insert it into pg_statistic_ext */
526 htup = heap_form_tuple(statrel->rd_att, values, nulls);
527 CatalogTupleInsert(statrel, htup);
528 heap_freetuple(htup);
529
531
532 /*
533 * We used to create the pg_statistic_ext_data tuple too, but it's not
534 * clear what value should the stxdinherit flag have (it depends on
535 * whether the rel is partitioned, contains data, etc.)
536 */
537
538 InvokeObjectPostCreateHook(StatisticExtRelationId, statoid, 0);
539
540 /*
541 * Invalidate relcache so that others see the new statistics object.
542 */
544
546
547 /*
548 * Add an AUTO dependency on each column used in the stats, so that the
549 * stats object goes away if any or all of them get dropped.
550 */
551 ObjectAddressSet(myself, StatisticExtRelationId, statoid);
552
553 /* add dependencies for plain column references */
554 for (i = 0; i < nattnums; i++)
555 {
556 ObjectAddressSubSet(parentobject, RelationRelationId, relid, attnums[i]);
557 recordDependencyOn(&myself, &parentobject, DEPENDENCY_AUTO);
558 }
559
560 /*
561 * If there are no dependencies on a column, give the statistics object an
562 * auto dependency on the whole table. In most cases, this will be
563 * redundant, but it might not be if the statistics expressions contain no
564 * Vars (which might seem strange but possible). This is consistent with
565 * what we do for indexes in index_create.
566 *
567 * XXX We intentionally don't consider the expressions before adding this
568 * dependency, because recordDependencyOnSingleRelExpr may not create any
569 * dependencies for whole-row Vars.
570 */
571 if (!nattnums)
572 {
573 ObjectAddressSet(parentobject, RelationRelationId, relid);
574 recordDependencyOn(&myself, &parentobject, DEPENDENCY_AUTO);
575 }
576
577 /*
578 * Store dependencies on anything mentioned in statistics expressions,
579 * just like we do for index expressions.
580 */
581 if (stxexprs)
583 (Node *) stxexprs,
584 relid,
586 DEPENDENCY_AUTO, false);
587
588 /*
589 * Also add dependencies on namespace and owner. These are required
590 * because the stats object might have a different namespace and/or owner
591 * than the underlying table(s).
592 */
593 ObjectAddressSet(parentobject, NamespaceRelationId, namespaceId);
594 recordDependencyOn(&myself, &parentobject, DEPENDENCY_NORMAL);
595
596 recordDependencyOnOwner(StatisticExtRelationId, statoid, stxowner);
597
598 /*
599 * XXX probably there should be a recordDependencyOnCurrentExtension call
600 * here too, but we'd have to add support for ALTER EXTENSION ADD/DROP
601 * STATISTICS, which is more work than it seems worth.
602 */
603
604 /* Add any requested comment */
605 if (stmt->stxcomment != NULL)
606 CreateComments(statoid, StatisticExtRelationId, 0,
607 stmt->stxcomment);
608
609 /* Return stats object's address */
610 return myself;
611}
612
613/*
614 * ALTER STATISTICS
615 */
618{
619 Relation rel;
620 Oid stxoid;
621 HeapTuple oldtup;
622 HeapTuple newtup;
623 Datum repl_val[Natts_pg_statistic_ext];
624 bool repl_null[Natts_pg_statistic_ext];
625 bool repl_repl[Natts_pg_statistic_ext];
626 ObjectAddress address;
627 int newtarget = 0;
628 bool newtarget_default;
629
630 /* -1 was used in previous versions for the default setting */
631 if (stmt->stxstattarget && intVal(stmt->stxstattarget) != -1)
632 {
633 newtarget = intVal(stmt->stxstattarget);
634 newtarget_default = false;
635 }
636 else
637 newtarget_default = true;
638
639 if (!newtarget_default)
640 {
641 /* Limit statistics target to a sane range */
642 if (newtarget < 0)
643 {
645 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
646 errmsg("statistics target %d is too low",
647 newtarget)));
648 }
649 else if (newtarget > MAX_STATISTICS_TARGET)
650 {
651 newtarget = MAX_STATISTICS_TARGET;
653 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
654 errmsg("lowering statistics target to %d",
655 newtarget)));
656 }
657 }
658
659 /* lookup OID of the statistics object */
660 stxoid = get_statistics_object_oid(stmt->defnames, stmt->missing_ok);
661
662 /*
663 * If we got here and the OID is not valid, it means the statistics object
664 * does not exist, but the command specified IF EXISTS. So report this as
665 * a simple NOTICE and we're done.
666 */
667 if (!OidIsValid(stxoid))
668 {
669 char *schemaname;
670 char *statname;
671
672 Assert(stmt->missing_ok);
673
674 DeconstructQualifiedName(stmt->defnames, &schemaname, &statname);
675
676 if (schemaname)
678 (errmsg("statistics object \"%s.%s\" does not exist, skipping",
679 schemaname, statname)));
680 else
682 (errmsg("statistics object \"%s\" does not exist, skipping",
683 statname)));
684
686 }
687
688 /* Search pg_statistic_ext */
689 rel = table_open(StatisticExtRelationId, RowExclusiveLock);
690
691 oldtup = SearchSysCache1(STATEXTOID, ObjectIdGetDatum(stxoid));
692 if (!HeapTupleIsValid(oldtup))
693 elog(ERROR, "cache lookup failed for extended statistics object %u", stxoid);
694
695 /* Must be owner of the existing statistics object */
696 if (!object_ownercheck(StatisticExtRelationId, stxoid, GetUserId()))
698 NameListToString(stmt->defnames));
699
700 /* Build new tuple. */
701 memset(repl_val, 0, sizeof(repl_val));
702 memset(repl_null, false, sizeof(repl_null));
703 memset(repl_repl, false, sizeof(repl_repl));
704
705 /* replace the stxstattarget column */
706 repl_repl[Anum_pg_statistic_ext_stxstattarget - 1] = true;
707 if (!newtarget_default)
708 repl_val[Anum_pg_statistic_ext_stxstattarget - 1] = Int16GetDatum(newtarget);
709 else
710 repl_null[Anum_pg_statistic_ext_stxstattarget - 1] = true;
711
712 newtup = heap_modify_tuple(oldtup, RelationGetDescr(rel),
713 repl_val, repl_null, repl_repl);
714
715 /* Update system catalog. */
716 CatalogTupleUpdate(rel, &newtup->t_self, newtup);
717
718 InvokeObjectPostAlterHook(StatisticExtRelationId, stxoid, 0);
719
720 ObjectAddressSet(address, StatisticExtRelationId, stxoid);
721
722 /*
723 * NOTE: because we only support altering the statistics target, not the
724 * other fields, there is no need to update dependencies.
725 */
726
727 heap_freetuple(newtup);
728 ReleaseSysCache(oldtup);
729
731
732 return address;
733}
734
735/*
736 * Delete entry in pg_statistic_ext_data catalog. We don't know if the row
737 * exists, so don't error out.
738 */
739void
740RemoveStatisticsDataById(Oid statsOid, bool inh)
741{
742 Relation relation;
743 HeapTuple tup;
744
745 relation = table_open(StatisticExtDataRelationId, RowExclusiveLock);
746
747 tup = SearchSysCache2(STATEXTDATASTXOID, ObjectIdGetDatum(statsOid),
748 BoolGetDatum(inh));
749
750 /* We don't know if the data row for inh value exists. */
751 if (HeapTupleIsValid(tup))
752 {
753 CatalogTupleDelete(relation, &tup->t_self);
754
755 ReleaseSysCache(tup);
756 }
757
758 table_close(relation, RowExclusiveLock);
759}
760
761/*
762 * Guts of statistics object deletion.
763 */
764void
766{
767 Relation relation;
768 Relation rel;
769 HeapTuple tup;
770 Form_pg_statistic_ext statext;
771 Oid relid;
772
773 /*
774 * Delete the pg_statistic_ext tuple. Also send out a cache inval on the
775 * associated table, so that dependent plans will be rebuilt.
776 */
777 relation = table_open(StatisticExtRelationId, RowExclusiveLock);
778
779 tup = SearchSysCache1(STATEXTOID, ObjectIdGetDatum(statsOid));
780
781 if (!HeapTupleIsValid(tup)) /* should not happen */
782 elog(ERROR, "cache lookup failed for statistics object %u", statsOid);
783
784 statext = (Form_pg_statistic_ext) GETSTRUCT(tup);
785 relid = statext->stxrelid;
786
787 /*
788 * Delete the pg_statistic_ext_data tuples holding the actual statistical
789 * data. There might be data with/without inheritance, so attempt deleting
790 * both. We lock the user table first, to prevent other processes (e.g.
791 * DROP STATISTICS) from removing the row concurrently.
792 */
794
795 RemoveStatisticsDataById(statsOid, true);
796 RemoveStatisticsDataById(statsOid, false);
797
799
800 CatalogTupleDelete(relation, &tup->t_self);
801
802 ReleaseSysCache(tup);
803
804 /* Keep lock until the end of the transaction. */
805 table_close(rel, NoLock);
806
807 table_close(relation, RowExclusiveLock);
808}
809
810/*
811 * Select a nonconflicting name for a new statistics object.
812 *
813 * name1, name2, and label are used the same way as for makeObjectName(),
814 * except that the label can't be NULL; digits will be appended to the label
815 * if needed to create a name that is unique within the specified namespace.
816 *
817 * Returns a palloc'd string.
818 *
819 * Note: it is theoretically possible to get a collision anyway, if someone
820 * else chooses the same name concurrently. This is fairly unlikely to be
821 * a problem in practice, especially if one is holding a share update
822 * exclusive lock on the relation identified by name1. However, if choosing
823 * multiple names within a single command, you'd better create the new object
824 * and do CommandCounterIncrement before choosing the next one!
825 */
826static char *
827ChooseExtendedStatisticName(const char *name1, const char *name2,
828 const char *label, Oid namespaceid)
829{
830 int pass = 0;
831 char *stxname = NULL;
832 char modlabel[NAMEDATALEN];
833
834 /* try the unmodified label first */
835 strlcpy(modlabel, label, sizeof(modlabel));
836
837 for (;;)
838 {
839 Oid existingstats;
840
841 stxname = makeObjectName(name1, name2, modlabel);
842
843 existingstats = GetSysCacheOid2(STATEXTNAMENSP, Anum_pg_statistic_ext_oid,
844 PointerGetDatum(stxname),
845 ObjectIdGetDatum(namespaceid));
846 if (!OidIsValid(existingstats))
847 break;
848
849 /* found a conflict, so try a new name component */
850 pfree(stxname);
851 snprintf(modlabel, sizeof(modlabel), "%s%d", label, ++pass);
852 }
853
854 return stxname;
855}
856
857/*
858 * Generate "name2" for a new statistics object given the list of column
859 * names for it. This will be passed to ChooseExtendedStatisticName along
860 * with the parent table name and a suitable label.
861 *
862 * We know that less than NAMEDATALEN characters will actually be used,
863 * so we can truncate the result once we've generated that many.
864 *
865 * XXX see also ChooseForeignKeyConstraintNameAddition and
866 * ChooseIndexNameAddition.
867 */
868static char *
870{
871 char buf[NAMEDATALEN * 2];
872 int buflen = 0;
873 ListCell *lc;
874
875 buf[0] = '\0';
876 foreach(lc, exprs)
877 {
878 StatsElem *selem = (StatsElem *) lfirst(lc);
879 const char *name;
880
881 /* It should be one of these, but just skip if it happens not to be */
882 if (!IsA(selem, StatsElem))
883 continue;
884
885 name = selem->name;
886
887 if (buflen > 0)
888 buf[buflen++] = '_'; /* insert _ between names */
889
890 /*
891 * We use fixed 'expr' for expressions, which have empty column names.
892 * For indexes this is handled in ChooseIndexColumnNames, but we have
893 * no such function for stats and it does not seem worth adding. If a
894 * better name is needed, the user can specify it explicitly.
895 */
896 if (!name)
897 name = "expr";
898
899 /*
900 * At this point we have buflen <= NAMEDATALEN. name should be less
901 * than NAMEDATALEN already, but use strlcpy for paranoia.
902 */
903 strlcpy(buf + buflen, name, NAMEDATALEN);
904 buflen += strlen(buf + buflen);
905 if (buflen >= NAMEDATALEN)
906 break;
907 }
908 return pstrdup(buf);
909}
910
911/*
912 * StatisticsGetRelation: given a statistics object's OID, get the OID of
913 * the relation it is defined on. Uses the system cache.
914 */
915Oid
916StatisticsGetRelation(Oid statId, bool missing_ok)
917{
918 HeapTuple tuple;
920 Oid result;
921
922 tuple = SearchSysCache1(STATEXTOID, ObjectIdGetDatum(statId));
923 if (!HeapTupleIsValid(tuple))
924 {
925 if (missing_ok)
926 return InvalidOid;
927 elog(ERROR, "cache lookup failed for statistics object %u", statId);
928 }
929 stx = (Form_pg_statistic_ext) GETSTRUCT(tuple);
930 Assert(stx->oid == statId);
931
932 result = stx->stxrelid;
933 ReleaseSysCache(tuple);
934 return result;
935}
@ ACLCHECK_NOT_OWNER
Definition: acl.h:185
void aclcheck_error(AclResult aclerr, ObjectType objtype, const char *objectname)
Definition: aclchk.c:2622
bool object_ownercheck(Oid classid, Oid objectid, Oid roleid)
Definition: aclchk.c:4058
ArrayType * construct_array_builtin(Datum *elems, int nelems, Oid elmtype)
Definition: arrayfuncs.c:3381
int16 AttrNumber
Definition: attnum.h:21
int bms_next_member(const Bitmapset *a, int prevbit)
Definition: bitmapset.c:1306
static Datum values[MAXATTR]
Definition: bootstrap.c:151
#define CStringGetTextDatum(s)
Definition: builtins.h:97
#define Assert(condition)
Definition: c.h:815
int16_t int16
Definition: c.h:483
#define lengthof(array)
Definition: c.h:745
#define OidIsValid(objectId)
Definition: c.h:732
bool IsSystemRelation(Relation relation)
Definition: catalog.c:73
Oid GetNewOidWithIndex(Relation relation, Oid indexId, AttrNumber oidcolumn)
Definition: catalog.c:419
void CreateComments(Oid oid, Oid classoid, int32 subid, const char *comment)
Definition: comment.c:143
void recordDependencyOnSingleRelExpr(const ObjectAddress *depender, Node *expr, Oid relId, DependencyType behavior, DependencyType self_behavior, bool reverse_self)
Definition: dependency.c:1596
@ DEPENDENCY_AUTO
Definition: dependency.h:34
@ DEPENDENCY_NORMAL
Definition: dependency.h:33
struct typedefs * types
Definition: ecpg.c:30
int errcode(int sqlerrcode)
Definition: elog.c:853
int errmsg(const char *fmt,...)
Definition: elog.c:1070
#define WARNING
Definition: elog.h:36
#define ERROR
Definition: elog.h:39
#define elog(elevel,...)
Definition: elog.h:225
#define NOTICE
Definition: elog.h:35
#define ereport(elevel,...)
Definition: elog.h:149
bool equal(const void *a, const void *b)
Definition: equalfuncs.c:223
char * format_type_be(Oid type_oid)
Definition: format_type.c:343
bool allowSystemTableMods
Definition: globals.c:129
HeapTuple heap_modify_tuple(HeapTuple tuple, TupleDesc tupleDesc, const Datum *replValues, const bool *replIsnull, const bool *doReplace)
Definition: heaptuple.c:1210
HeapTuple heap_form_tuple(TupleDesc tupleDescriptor, const Datum *values, const bool *isnull)
Definition: heaptuple.c:1117
void heap_freetuple(HeapTuple htup)
Definition: heaptuple.c:1435
#define HeapTupleIsValid(tuple)
Definition: htup.h:78
static void * GETSTRUCT(const HeapTupleData *tuple)
Definition: htup_details.h:728
#define stmt
Definition: indent_codes.h:59
char * makeObjectName(const char *name1, const char *name2, const char *label)
Definition: indexcmds.c:2524
void CatalogTupleUpdate(Relation heapRel, ItemPointer otid, HeapTuple tup)
Definition: indexing.c:313
void CatalogTupleInsert(Relation heapRel, HeapTuple tup)
Definition: indexing.c:233
void CatalogTupleDelete(Relation heapRel, ItemPointer tid)
Definition: indexing.c:365
int2vector * buildint2vector(const int16 *int2s, int n)
Definition: int.c:114
void CacheInvalidateRelcache(Relation relation)
Definition: inval.c:1556
void CacheInvalidateRelcacheByRelid(Oid relid)
Definition: inval.c:1612
int b
Definition: isn.c:69
int a
Definition: isn.c:68
int i
Definition: isn.c:72
if(TABLE==NULL||TABLE_index==NULL)
Definition: isn.c:76
List * lappend(List *list, void *datum)
Definition: list.c:339
#define NoLock
Definition: lockdefs.h:34
#define ShareUpdateExclusiveLock
Definition: lockdefs.h:39
#define RowExclusiveLock
Definition: lockdefs.h:38
char get_attgenerated(Oid relid, AttrNumber attnum)
Definition: lsyscache.c:889
char * get_attname(Oid relid, AttrNumber attnum, bool missing_ok)
Definition: lsyscache.c:828
char * pstrdup(const char *in)
Definition: mcxt.c:1696
void pfree(void *pointer)
Definition: mcxt.c:1521
Oid GetUserId(void)
Definition: miscinit.c:517
void namestrcpy(Name name, const char *str)
Definition: name.c:233
char * NameListToString(const List *names)
Definition: namespace.c:3594
Oid QualifiedNameGetCreationNamespace(const List *names, char **objname_p)
Definition: namespace.c:3487
Oid get_statistics_object_oid(List *names, bool missing_ok)
Definition: namespace.c:2575
void DeconstructQualifiedName(const List *names, char **nspname_p, char **objname_p)
Definition: namespace.c:3301
Oid exprType(const Node *expr)
Definition: nodeFuncs.c:42
#define IsA(nodeptr, _type_)
Definition: nodes.h:158
#define InvokeObjectPostCreateHook(classId, objectId, subId)
Definition: objectaccess.h:173
#define InvokeObjectPostAlterHook(classId, objectId, subId)
Definition: objectaccess.h:197
ObjectType get_relkind_objtype(char relkind)
const ObjectAddress InvalidObjectAddress
#define ObjectAddressSet(addr, class_id, object_id)
Definition: objectaddress.h:40
#define ObjectAddressSubSet(addr, class_id, object_id, object_sub_id)
Definition: objectaddress.h:33
char * nodeToString(const void *obj)
Definition: outfuncs.c:794
@ OBJECT_STATISTIC_EXT
Definition: parsenodes.h:2351
NameData attname
Definition: pg_attribute.h:41
int16 attnum
Definition: pg_attribute.h:74
FormData_pg_attribute * Form_pg_attribute
Definition: pg_attribute.h:200
static char * label
int errdetail_relkind_not_supported(char relkind)
Definition: pg_class.c:24
#define NAMEDATALEN
void recordDependencyOn(const ObjectAddress *depender, const ObjectAddress *referenced, DependencyType behavior)
Definition: pg_depend.c:45
#define lfirst(lc)
Definition: pg_list.h:172
#define lfirst_node(type, lc)
Definition: pg_list.h:176
static int list_length(const List *l)
Definition: pg_list.h:152
#define NIL
Definition: pg_list.h:68
void recordDependencyOnOwner(Oid classId, Oid objectId, Oid owner)
Definition: pg_shdepend.c:168
FormData_pg_statistic_ext * Form_pg_statistic_ext
static char * buf
Definition: pg_test_fsync.c:72
#define snprintf
Definition: port.h:239
#define qsort(a, b, c, d)
Definition: port.h:475
size_t strlcpy(char *dst, const char *src, size_t siz)
Definition: strlcpy.c:45
static Datum PointerGetDatum(const void *X)
Definition: postgres.h:327
uintptr_t Datum
Definition: postgres.h:69
static Datum Int16GetDatum(int16 X)
Definition: postgres.h:177
static Datum BoolGetDatum(bool X)
Definition: postgres.h:107
static Datum ObjectIdGetDatum(Oid X)
Definition: postgres.h:257
static Datum NameGetDatum(const NameData *X)
Definition: postgres.h:378
static Datum CStringGetDatum(const char *X)
Definition: postgres.h:355
static Datum CharGetDatum(char X)
Definition: postgres.h:127
#define InvalidOid
Definition: postgres_ext.h:37
unsigned int Oid
Definition: postgres_ext.h:32
#define RelationGetRelid(relation)
Definition: rel.h:512
#define RelationGetDescr(relation)
Definition: rel.h:538
#define RelationGetRelationName(relation)
Definition: rel.h:546
#define RelationGetNamespace(relation)
Definition: rel.h:553
struct @10::@11 av[32]
void relation_close(Relation relation, LOCKMODE lockmode)
Definition: relation.c:205
Relation relation_openrv(const RangeVar *relation, LOCKMODE lockmode)
Definition: relation.c:137
#define STATS_MAX_DIMENSIONS
Definition: statistics.h:19
ObjectAddress AlterStatistics(AlterStatsStmt *stmt)
Definition: statscmds.c:617
ObjectAddress CreateStatistics(CreateStatsStmt *stmt)
Definition: statscmds.c:62
static char * ChooseExtendedStatisticNameAddition(List *exprs)
Definition: statscmds.c:869
void RemoveStatisticsDataById(Oid statsOid, bool inh)
Definition: statscmds.c:740
static char * ChooseExtendedStatisticName(const char *name1, const char *name2, const char *label, Oid namespaceid)
Definition: statscmds.c:827
void RemoveStatisticsById(Oid statsOid)
Definition: statscmds.c:765
static int compare_int16(const void *a, const void *b)
Definition: statscmds.c:49
Oid StatisticsGetRelation(Oid statId, bool missing_ok)
Definition: statscmds.c:916
#define ERRCODE_DUPLICATE_OBJECT
Definition: streamutil.c:30
ItemPointerData t_self
Definition: htup.h:65
Definition: pg_list.h:54
Definition: nodes.h:129
TupleDesc rd_att
Definition: rel.h:112
Form_pg_class rd_rel
Definition: rel.h:111
char * name
Definition: parsenodes.h:3481
Node * expr
Definition: parsenodes.h:3482
Definition: primnodes.h:262
AttrNumber varattno
Definition: primnodes.h:274
Definition: c.h:672
Definition: c.h:698
#define FirstLowInvalidHeapAttributeNumber
Definition: sysattr.h:27
void ReleaseSysCache(HeapTuple tuple)
Definition: syscache.c:269
HeapTuple SearchSysCache1(int cacheId, Datum key1)
Definition: syscache.c:221
HeapTuple SearchSysCache2(int cacheId, Datum key1, Datum key2)
Definition: syscache.c:232
HeapTuple SearchSysCacheAttName(Oid relid, const char *attname)
Definition: syscache.c:480
#define SearchSysCacheExists2(cacheId, key1, key2)
Definition: syscache.h:102
#define GetSysCacheOid2(cacheId, oidcol, key1, key2)
Definition: syscache.h:111
void table_close(Relation relation, LOCKMODE lockmode)
Definition: table.c:126
Relation table_open(Oid relationId, LOCKMODE lockmode)
Definition: table.c:40
TypeCacheEntry * lookup_type_cache(Oid type_id, int flags)
Definition: typcache.c:386
#define TYPECACHE_LT_OPR
Definition: typcache.h:138
#define MAX_STATISTICS_TARGET
Definition: vacuum.h:323
#define intVal(v)
Definition: value.h:79
#define strVal(v)
Definition: value.h:82
void pull_varattnos(Node *node, Index varno, Bitmapset **varattnos)
Definition: var.c:296
const char * type
const char * name