Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * plancat.c
4 : * routines for accessing the system catalogs
5 : *
6 : *
7 : * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
8 : * Portions Copyright (c) 1994, Regents of the University of California
9 : *
10 : *
11 : * IDENTIFICATION
12 : * src/backend/optimizer/util/plancat.c
13 : *
14 : *-------------------------------------------------------------------------
15 : */
16 : #include "postgres.h"
17 :
18 : #include <math.h>
19 :
20 : #include "access/genam.h"
21 : #include "access/htup_details.h"
22 : #include "access/nbtree.h"
23 : #include "access/sysattr.h"
24 : #include "access/table.h"
25 : #include "access/tableam.h"
26 : #include "access/transam.h"
27 : #include "access/xlog.h"
28 : #include "catalog/catalog.h"
29 : #include "catalog/heap.h"
30 : #include "catalog/pg_am.h"
31 : #include "catalog/pg_proc.h"
32 : #include "catalog/pg_statistic_ext.h"
33 : #include "catalog/pg_statistic_ext_data.h"
34 : #include "foreign/fdwapi.h"
35 : #include "miscadmin.h"
36 : #include "nodes/makefuncs.h"
37 : #include "nodes/nodeFuncs.h"
38 : #include "nodes/supportnodes.h"
39 : #include "optimizer/cost.h"
40 : #include "optimizer/optimizer.h"
41 : #include "optimizer/plancat.h"
42 : #include "parser/parse_relation.h"
43 : #include "parser/parsetree.h"
44 : #include "partitioning/partdesc.h"
45 : #include "rewrite/rewriteHandler.h"
46 : #include "rewrite/rewriteManip.h"
47 : #include "statistics/statistics.h"
48 : #include "storage/bufmgr.h"
49 : #include "tcop/tcopprot.h"
50 : #include "utils/builtins.h"
51 : #include "utils/lsyscache.h"
52 : #include "utils/partcache.h"
53 : #include "utils/rel.h"
54 : #include "utils/snapmgr.h"
55 : #include "utils/syscache.h"
56 :
57 : /* GUC parameter */
58 : int constraint_exclusion = CONSTRAINT_EXCLUSION_PARTITION;
59 :
60 : /* Hook for plugins to get control in get_relation_info() */
61 : get_relation_info_hook_type get_relation_info_hook = NULL;
62 :
63 : typedef struct NotnullHashEntry
64 : {
65 : Oid relid; /* OID of the relation */
66 : Bitmapset *notnullattnums; /* attnums of NOT NULL columns */
67 : } NotnullHashEntry;
68 :
69 :
70 : static void get_relation_foreign_keys(PlannerInfo *root, RelOptInfo *rel,
71 : Relation relation, bool inhparent);
72 : static bool infer_collation_opclass_match(InferenceElem *elem, Relation idxRel,
73 : List *idxExprs);
74 : static List *get_relation_constraints(PlannerInfo *root,
75 : Oid relationObjectId, RelOptInfo *rel,
76 : bool include_noinherit,
77 : bool include_notnull,
78 : bool include_partition);
79 : static List *build_index_tlist(PlannerInfo *root, IndexOptInfo *index,
80 : Relation heapRelation);
81 : static List *get_relation_statistics(PlannerInfo *root, RelOptInfo *rel,
82 : Relation relation);
83 : static void set_relation_partition_info(PlannerInfo *root, RelOptInfo *rel,
84 : Relation relation);
85 : static PartitionScheme find_partition_scheme(PlannerInfo *root,
86 : Relation relation);
87 : static void set_baserel_partition_key_exprs(Relation relation,
88 : RelOptInfo *rel);
89 : static void set_baserel_partition_constraint(Relation relation,
90 : RelOptInfo *rel);
91 :
92 :
93 : /*
94 : * get_relation_info -
95 : * Retrieves catalog information for a given relation.
96 : *
97 : * Given the Oid of the relation, return the following info into fields
98 : * of the RelOptInfo struct:
99 : *
100 : * min_attr lowest valid AttrNumber
101 : * max_attr highest valid AttrNumber
102 : * indexlist list of IndexOptInfos for relation's indexes
103 : * statlist list of StatisticExtInfo for relation's statistic objects
104 : * serverid if it's a foreign table, the server OID
105 : * fdwroutine if it's a foreign table, the FDW function pointers
106 : * pages number of pages
107 : * tuples number of tuples
108 : * rel_parallel_workers user-defined number of parallel workers
109 : *
110 : * Also, add information about the relation's foreign keys to root->fkey_list.
111 : *
112 : * Also, initialize the attr_needed[] and attr_widths[] arrays. In most
113 : * cases these are left as zeroes, but sometimes we need to compute attr
114 : * widths here, and we may as well cache the results for costsize.c.
115 : *
116 : * If inhparent is true, all we need to do is set up the attr arrays:
117 : * the RelOptInfo actually represents the appendrel formed by an inheritance
118 : * tree, and so the parent rel's physical size and index information isn't
119 : * important for it, however, for partitioned tables, we do populate the
120 : * indexlist as the planner uses unique indexes as unique proofs for certain
121 : * optimizations.
122 : */
123 : void
124 472746 : get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
125 : RelOptInfo *rel)
126 : {
127 472746 : Index varno = rel->relid;
128 : Relation relation;
129 : bool hasindex;
130 472746 : List *indexinfos = NIL;
131 :
132 : /*
133 : * We need not lock the relation since it was already locked, either by
134 : * the rewriter or when expand_inherited_rtentry() added it to the query's
135 : * rangetable.
136 : */
137 472746 : relation = table_open(relationObjectId, NoLock);
138 :
139 : /*
140 : * Relations without a table AM can be used in a query only if they are of
141 : * special-cased relkinds. This check prevents us from crashing later if,
142 : * for example, a view's ON SELECT rule has gone missing. Note that
143 : * table_open() already rejected indexes and composite types; spell the
144 : * error the same way it does.
145 : */
146 472746 : if (!relation->rd_tableam)
147 : {
148 19514 : if (!(relation->rd_rel->relkind == RELKIND_FOREIGN_TABLE ||
149 17022 : relation->rd_rel->relkind == RELKIND_PARTITIONED_TABLE))
150 0 : ereport(ERROR,
151 : (errcode(ERRCODE_WRONG_OBJECT_TYPE),
152 : errmsg("cannot open relation \"%s\"",
153 : RelationGetRelationName(relation)),
154 : errdetail_relkind_not_supported(relation->rd_rel->relkind)));
155 : }
156 :
157 : /* Temporary and unlogged relations are inaccessible during recovery. */
158 472746 : if (!RelationIsPermanent(relation) && RecoveryInProgress())
159 0 : ereport(ERROR,
160 : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
161 : errmsg("cannot access temporary or unlogged relations during recovery")));
162 :
163 472746 : rel->min_attr = FirstLowInvalidHeapAttributeNumber + 1;
164 472746 : rel->max_attr = RelationGetNumberOfAttributes(relation);
165 472746 : rel->reltablespace = RelationGetForm(relation)->reltablespace;
166 :
167 : Assert(rel->max_attr >= rel->min_attr);
168 472746 : rel->attr_needed = (Relids *)
169 472746 : palloc0((rel->max_attr - rel->min_attr + 1) * sizeof(Relids));
170 472746 : rel->attr_widths = (int32 *)
171 472746 : palloc0((rel->max_attr - rel->min_attr + 1) * sizeof(int32));
172 :
173 : /*
174 : * Record which columns are defined as NOT NULL. We leave this
175 : * unpopulated for non-partitioned inheritance parent relations as it's
176 : * ambiguous as to what it means. Some child tables may have a NOT NULL
177 : * constraint for a column while others may not. We could work harder and
178 : * build a unioned set of all child relations notnullattnums, but there's
179 : * currently no need. The RelOptInfo corresponding to the !inh
180 : * RangeTblEntry does get populated.
181 : */
182 472746 : if (!inhparent || relation->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
183 435170 : rel->notnullattnums = find_relation_notnullatts(root, relationObjectId);
184 :
185 : /*
186 : * Estimate relation size --- unless it's an inheritance parent, in which
187 : * case the size we want is not the rel's own size but the size of its
188 : * inheritance tree. That will be computed in set_append_rel_size().
189 : */
190 472746 : if (!inhparent)
191 418188 : estimate_rel_size(relation, rel->attr_widths - rel->min_attr,
192 418188 : &rel->pages, &rel->tuples, &rel->allvisfrac);
193 :
194 : /* Retrieve the parallel_workers reloption, or -1 if not set. */
195 472746 : rel->rel_parallel_workers = RelationGetParallelWorkers(relation, -1);
196 :
197 : /*
198 : * Make list of indexes. Ignore indexes on system catalogs if told to.
199 : * Don't bother with indexes from traditional inheritance parents. For
200 : * partitioned tables, we need a list of at least unique indexes as these
201 : * serve as unique proofs for certain planner optimizations. However,
202 : * let's not discriminate here and just record all partitioned indexes
203 : * whether they're unique indexes or not.
204 : */
205 472746 : if ((inhparent && relation->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
206 435170 : || (IgnoreSystemIndexes && IsSystemRelation(relation)))
207 37576 : hasindex = false;
208 : else
209 435170 : hasindex = relation->rd_rel->relhasindex;
210 :
211 472746 : if (hasindex)
212 : {
213 : List *indexoidlist;
214 : LOCKMODE lmode;
215 : ListCell *l;
216 :
217 352316 : indexoidlist = RelationGetIndexList(relation);
218 :
219 : /*
220 : * For each index, we get the same type of lock that the executor will
221 : * need, and do not release it. This saves a couple of trips to the
222 : * shared lock manager while not creating any real loss of
223 : * concurrency, because no schema changes could be happening on the
224 : * index while we hold lock on the parent rel, and no lock type used
225 : * for queries blocks any other kind of index operation.
226 : */
227 352316 : lmode = root->simple_rte_array[varno]->rellockmode;
228 :
229 1096010 : foreach(l, indexoidlist)
230 : {
231 743694 : Oid indexoid = lfirst_oid(l);
232 : Relation indexRelation;
233 : Form_pg_index index;
234 743694 : IndexAmRoutine *amroutine = NULL;
235 : IndexOptInfo *info;
236 : int ncolumns,
237 : nkeycolumns;
238 : int i;
239 :
240 : /*
241 : * Extract info from the relation descriptor for the index.
242 : */
243 743694 : indexRelation = index_open(indexoid, lmode);
244 743694 : index = indexRelation->rd_index;
245 :
246 : /*
247 : * Ignore invalid indexes, since they can't safely be used for
248 : * queries. Note that this is OK because the data structure we
249 : * are constructing is only used by the planner --- the executor
250 : * still needs to insert into "invalid" indexes, if they're marked
251 : * indisready.
252 : */
253 743694 : if (!index->indisvalid)
254 : {
255 22 : index_close(indexRelation, NoLock);
256 22 : continue;
257 : }
258 :
259 : /*
260 : * If the index is valid, but cannot yet be used, ignore it; but
261 : * mark the plan we are generating as transient. See
262 : * src/backend/access/heap/README.HOT for discussion.
263 : */
264 743672 : if (index->indcheckxmin &&
265 302 : !TransactionIdPrecedes(HeapTupleHeaderGetXmin(indexRelation->rd_indextuple->t_data),
266 : TransactionXmin))
267 : {
268 294 : root->glob->transientPlan = true;
269 294 : index_close(indexRelation, NoLock);
270 294 : continue;
271 : }
272 :
273 743378 : info = makeNode(IndexOptInfo);
274 :
275 743378 : info->indexoid = index->indexrelid;
276 743378 : info->reltablespace =
277 743378 : RelationGetForm(indexRelation)->reltablespace;
278 743378 : info->rel = rel;
279 743378 : info->ncolumns = ncolumns = index->indnatts;
280 743378 : info->nkeycolumns = nkeycolumns = index->indnkeyatts;
281 :
282 743378 : info->indexkeys = (int *) palloc(sizeof(int) * ncolumns);
283 743378 : info->indexcollations = (Oid *) palloc(sizeof(Oid) * nkeycolumns);
284 743378 : info->opfamily = (Oid *) palloc(sizeof(Oid) * nkeycolumns);
285 743378 : info->opcintype = (Oid *) palloc(sizeof(Oid) * nkeycolumns);
286 743378 : info->canreturn = (bool *) palloc(sizeof(bool) * ncolumns);
287 :
288 2146634 : for (i = 0; i < ncolumns; i++)
289 : {
290 1403256 : info->indexkeys[i] = index->indkey.values[i];
291 1403256 : info->canreturn[i] = index_can_return(indexRelation, i + 1);
292 : }
293 :
294 2146216 : for (i = 0; i < nkeycolumns; i++)
295 : {
296 1402838 : info->opfamily[i] = indexRelation->rd_opfamily[i];
297 1402838 : info->opcintype[i] = indexRelation->rd_opcintype[i];
298 1402838 : info->indexcollations[i] = indexRelation->rd_indcollation[i];
299 : }
300 :
301 743378 : info->relam = indexRelation->rd_rel->relam;
302 :
303 : /*
304 : * We don't have an AM for partitioned indexes, so we'll just
305 : * NULLify the AM related fields for those.
306 : */
307 743378 : if (indexRelation->rd_rel->relkind != RELKIND_PARTITIONED_INDEX)
308 : {
309 : /* We copy just the fields we need, not all of rd_indam */
310 736744 : amroutine = indexRelation->rd_indam;
311 736744 : info->amcanorderbyop = amroutine->amcanorderbyop;
312 736744 : info->amoptionalkey = amroutine->amoptionalkey;
313 736744 : info->amsearcharray = amroutine->amsearcharray;
314 736744 : info->amsearchnulls = amroutine->amsearchnulls;
315 736744 : info->amcanparallel = amroutine->amcanparallel;
316 736744 : info->amhasgettuple = (amroutine->amgettuple != NULL);
317 1473488 : info->amhasgetbitmap = amroutine->amgetbitmap != NULL &&
318 736744 : relation->rd_tableam->scan_bitmap_next_tuple != NULL;
319 1451400 : info->amcanmarkpos = (amroutine->ammarkpos != NULL &&
320 714656 : amroutine->amrestrpos != NULL);
321 736744 : info->amcostestimate = amroutine->amcostestimate;
322 : Assert(info->amcostestimate != NULL);
323 :
324 : /* Fetch index opclass options */
325 736744 : info->opclassoptions = RelationGetIndexAttOptions(indexRelation, true);
326 :
327 : /*
328 : * Fetch the ordering information for the index, if any.
329 : */
330 736744 : if (info->relam == BTREE_AM_OID)
331 : {
332 : /*
333 : * If it's a btree index, we can use its opfamily OIDs
334 : * directly as the sort ordering opfamily OIDs.
335 : */
336 : Assert(amroutine->amcanorder);
337 :
338 714656 : info->sortopfamily = info->opfamily;
339 714656 : info->reverse_sort = (bool *) palloc(sizeof(bool) * nkeycolumns);
340 714656 : info->nulls_first = (bool *) palloc(sizeof(bool) * nkeycolumns);
341 :
342 1827960 : for (i = 0; i < nkeycolumns; i++)
343 : {
344 1113304 : int16 opt = indexRelation->rd_indoption[i];
345 :
346 1113304 : info->reverse_sort[i] = (opt & INDOPTION_DESC) != 0;
347 1113304 : info->nulls_first[i] = (opt & INDOPTION_NULLS_FIRST) != 0;
348 : }
349 : }
350 22088 : else if (amroutine->amcanorder)
351 : {
352 : /*
353 : * Otherwise, identify the corresponding btree opfamilies
354 : * by trying to map this index's "<" operators into btree.
355 : * Since "<" uniquely defines the behavior of a sort
356 : * order, this is a sufficient test.
357 : *
358 : * XXX This method is rather slow and complicated. It'd
359 : * be better to have a way to explicitly declare the
360 : * corresponding btree opfamily for each opfamily of the
361 : * other index type.
362 : */
363 0 : info->sortopfamily = (Oid *) palloc(sizeof(Oid) * nkeycolumns);
364 0 : info->reverse_sort = (bool *) palloc(sizeof(bool) * nkeycolumns);
365 0 : info->nulls_first = (bool *) palloc(sizeof(bool) * nkeycolumns);
366 :
367 0 : for (i = 0; i < nkeycolumns; i++)
368 : {
369 0 : int16 opt = indexRelation->rd_indoption[i];
370 : Oid ltopr;
371 : Oid opfamily;
372 : Oid opcintype;
373 : CompareType cmptype;
374 :
375 0 : info->reverse_sort[i] = (opt & INDOPTION_DESC) != 0;
376 0 : info->nulls_first[i] = (opt & INDOPTION_NULLS_FIRST) != 0;
377 :
378 0 : ltopr = get_opfamily_member_for_cmptype(info->opfamily[i],
379 0 : info->opcintype[i],
380 0 : info->opcintype[i],
381 : COMPARE_LT);
382 0 : if (OidIsValid(ltopr) &&
383 0 : get_ordering_op_properties(ltopr,
384 : &opfamily,
385 : &opcintype,
386 0 : &cmptype) &&
387 0 : opcintype == info->opcintype[i] &&
388 0 : cmptype == COMPARE_LT)
389 : {
390 : /* Successful mapping */
391 0 : info->sortopfamily[i] = opfamily;
392 : }
393 : else
394 : {
395 : /* Fail ... quietly treat index as unordered */
396 0 : info->sortopfamily = NULL;
397 0 : info->reverse_sort = NULL;
398 0 : info->nulls_first = NULL;
399 0 : break;
400 : }
401 : }
402 : }
403 : else
404 : {
405 22088 : info->sortopfamily = NULL;
406 22088 : info->reverse_sort = NULL;
407 22088 : info->nulls_first = NULL;
408 : }
409 : }
410 : else
411 : {
412 6634 : info->amcanorderbyop = false;
413 6634 : info->amoptionalkey = false;
414 6634 : info->amsearcharray = false;
415 6634 : info->amsearchnulls = false;
416 6634 : info->amcanparallel = false;
417 6634 : info->amhasgettuple = false;
418 6634 : info->amhasgetbitmap = false;
419 6634 : info->amcanmarkpos = false;
420 6634 : info->amcostestimate = NULL;
421 :
422 6634 : info->sortopfamily = NULL;
423 6634 : info->reverse_sort = NULL;
424 6634 : info->nulls_first = NULL;
425 : }
426 :
427 : /*
428 : * Fetch the index expressions and predicate, if any. We must
429 : * modify the copies we obtain from the relcache to have the
430 : * correct varno for the parent relation, so that they match up
431 : * correctly against qual clauses.
432 : */
433 743378 : info->indexprs = RelationGetIndexExpressions(indexRelation);
434 743378 : info->indpred = RelationGetIndexPredicate(indexRelation);
435 743378 : if (info->indexprs && varno != 1)
436 1938 : ChangeVarNodes((Node *) info->indexprs, 1, varno, 0);
437 743378 : if (info->indpred && varno != 1)
438 126 : ChangeVarNodes((Node *) info->indpred, 1, varno, 0);
439 :
440 : /* Build targetlist using the completed indexprs data */
441 743378 : info->indextlist = build_index_tlist(root, info, relation);
442 :
443 743378 : info->indrestrictinfo = NIL; /* set later, in indxpath.c */
444 743378 : info->predOK = false; /* set later, in indxpath.c */
445 743378 : info->unique = index->indisunique;
446 743378 : info->nullsnotdistinct = index->indnullsnotdistinct;
447 743378 : info->immediate = index->indimmediate;
448 743378 : info->hypothetical = false;
449 :
450 : /*
451 : * Estimate the index size. If it's not a partial index, we lock
452 : * the number-of-tuples estimate to equal the parent table; if it
453 : * is partial then we have to use the same methods as we would for
454 : * a table, except we can be sure that the index is not larger
455 : * than the table. We must ignore partitioned indexes here as
456 : * there are not physical indexes.
457 : */
458 743378 : if (indexRelation->rd_rel->relkind != RELKIND_PARTITIONED_INDEX)
459 : {
460 736744 : if (info->indpred == NIL)
461 : {
462 735760 : info->pages = RelationGetNumberOfBlocks(indexRelation);
463 735760 : info->tuples = rel->tuples;
464 : }
465 : else
466 : {
467 : double allvisfrac; /* dummy */
468 :
469 984 : estimate_rel_size(indexRelation, NULL,
470 984 : &info->pages, &info->tuples, &allvisfrac);
471 984 : if (info->tuples > rel->tuples)
472 18 : info->tuples = rel->tuples;
473 : }
474 :
475 : /*
476 : * Get tree height while we have the index open
477 : */
478 736744 : if (amroutine->amgettreeheight)
479 : {
480 714656 : info->tree_height = amroutine->amgettreeheight(indexRelation);
481 : }
482 : else
483 : {
484 : /* For other index types, just set it to "unknown" for now */
485 22088 : info->tree_height = -1;
486 : }
487 : }
488 : else
489 : {
490 : /* Zero these out for partitioned indexes */
491 6634 : info->pages = 0;
492 6634 : info->tuples = 0.0;
493 6634 : info->tree_height = -1;
494 : }
495 :
496 743378 : index_close(indexRelation, NoLock);
497 :
498 : /*
499 : * We've historically used lcons() here. It'd make more sense to
500 : * use lappend(), but that causes the planner to change behavior
501 : * in cases where two indexes seem equally attractive. For now,
502 : * stick with lcons() --- few tables should have so many indexes
503 : * that the O(N^2) behavior of lcons() is really a problem.
504 : */
505 743378 : indexinfos = lcons(info, indexinfos);
506 : }
507 :
508 352316 : list_free(indexoidlist);
509 : }
510 :
511 472746 : rel->indexlist = indexinfos;
512 :
513 472746 : rel->statlist = get_relation_statistics(root, rel, relation);
514 :
515 : /* Grab foreign-table info using the relcache, while we have it */
516 472746 : if (relation->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
517 : {
518 : /* Check if the access to foreign tables is restricted */
519 2492 : if (unlikely((restrict_nonsystem_relation_kind & RESTRICT_RELKIND_FOREIGN_TABLE) != 0))
520 : {
521 : /* there must not be built-in foreign tables */
522 : Assert(RelationGetRelid(relation) >= FirstNormalObjectId);
523 :
524 4 : ereport(ERROR,
525 : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
526 : errmsg("access to non-system foreign table is restricted")));
527 : }
528 :
529 2488 : rel->serverid = GetForeignServerIdByRelId(RelationGetRelid(relation));
530 2488 : rel->fdwroutine = GetFdwRoutineForRelation(relation, true);
531 : }
532 : else
533 : {
534 470254 : rel->serverid = InvalidOid;
535 470254 : rel->fdwroutine = NULL;
536 : }
537 :
538 : /* Collect info about relation's foreign keys, if relevant */
539 472728 : get_relation_foreign_keys(root, rel, relation, inhparent);
540 :
541 : /* Collect info about functions implemented by the rel's table AM. */
542 472728 : if (relation->rd_tableam &&
543 453232 : relation->rd_tableam->scan_set_tidrange != NULL &&
544 453232 : relation->rd_tableam->scan_getnextslot_tidrange != NULL)
545 453232 : rel->amflags |= AMFLAG_HAS_TID_RANGE;
546 :
547 : /*
548 : * Collect info about relation's partitioning scheme, if any. Only
549 : * inheritance parents may be partitioned.
550 : */
551 472728 : if (inhparent && relation->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
552 16982 : set_relation_partition_info(root, rel, relation);
553 :
554 472728 : table_close(relation, NoLock);
555 :
556 : /*
557 : * Allow a plugin to editorialize on the info we obtained from the
558 : * catalogs. Actions might include altering the assumed relation size,
559 : * removing an index, or adding a hypothetical index to the indexlist.
560 : */
561 472728 : if (get_relation_info_hook)
562 0 : (*get_relation_info_hook) (root, relationObjectId, inhparent, rel);
563 472728 : }
564 :
565 : /*
566 : * get_relation_foreign_keys -
567 : * Retrieves foreign key information for a given relation.
568 : *
569 : * ForeignKeyOptInfos for relevant foreign keys are created and added to
570 : * root->fkey_list. We do this now while we have the relcache entry open.
571 : * We could sometimes avoid making useless ForeignKeyOptInfos if we waited
572 : * until all RelOptInfos have been built, but the cost of re-opening the
573 : * relcache entries would probably exceed any savings.
574 : */
575 : static void
576 472728 : get_relation_foreign_keys(PlannerInfo *root, RelOptInfo *rel,
577 : Relation relation, bool inhparent)
578 : {
579 472728 : List *rtable = root->parse->rtable;
580 : List *cachedfkeys;
581 : ListCell *lc;
582 :
583 : /*
584 : * If it's not a baserel, we don't care about its FKs. Also, if the query
585 : * references only a single relation, we can skip the lookup since no FKs
586 : * could satisfy the requirements below.
587 : */
588 903606 : if (rel->reloptkind != RELOPT_BASEREL ||
589 430878 : list_length(rtable) < 2)
590 241890 : return;
591 :
592 : /*
593 : * If it's the parent of an inheritance tree, ignore its FKs. We could
594 : * make useful FK-based deductions if we found that all members of the
595 : * inheritance tree have equivalent FK constraints, but detecting that
596 : * would require code that hasn't been written.
597 : */
598 230838 : if (inhparent)
599 5574 : return;
600 :
601 : /*
602 : * Extract data about relation's FKs from the relcache. Note that this
603 : * list belongs to the relcache and might disappear in a cache flush, so
604 : * we must not do any further catalog access within this function.
605 : */
606 225264 : cachedfkeys = RelationGetFKeyList(relation);
607 :
608 : /*
609 : * Figure out which FKs are of interest for this query, and create
610 : * ForeignKeyOptInfos for them. We want only FKs that reference some
611 : * other RTE of the current query. In queries containing self-joins,
612 : * there might be more than one other RTE for a referenced table, and we
613 : * should make a ForeignKeyOptInfo for each occurrence.
614 : *
615 : * Ideally, we would ignore RTEs that correspond to non-baserels, but it's
616 : * too hard to identify those here, so we might end up making some useless
617 : * ForeignKeyOptInfos. If so, match_foreign_keys_to_quals() will remove
618 : * them again.
619 : */
620 227858 : foreach(lc, cachedfkeys)
621 : {
622 2594 : ForeignKeyCacheInfo *cachedfk = (ForeignKeyCacheInfo *) lfirst(lc);
623 : Index rti;
624 : ListCell *lc2;
625 :
626 : /* conrelid should always be that of the table we're considering */
627 : Assert(cachedfk->conrelid == RelationGetRelid(relation));
628 :
629 : /* skip constraints currently not enforced */
630 2594 : if (!cachedfk->conenforced)
631 18 : continue;
632 :
633 : /* Scan to find other RTEs matching confrelid */
634 2576 : rti = 0;
635 11396 : foreach(lc2, rtable)
636 : {
637 8820 : RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc2);
638 : ForeignKeyOptInfo *info;
639 :
640 8820 : rti++;
641 : /* Ignore if not the correct table */
642 8820 : if (rte->rtekind != RTE_RELATION ||
643 5494 : rte->relid != cachedfk->confrelid)
644 6650 : continue;
645 : /* Ignore if it's an inheritance parent; doesn't really match */
646 2170 : if (rte->inh)
647 258 : continue;
648 : /* Ignore self-referential FKs; we only care about joins */
649 1912 : if (rti == rel->relid)
650 132 : continue;
651 :
652 : /* OK, let's make an entry */
653 1780 : info = makeNode(ForeignKeyOptInfo);
654 1780 : info->con_relid = rel->relid;
655 1780 : info->ref_relid = rti;
656 1780 : info->nkeys = cachedfk->nkeys;
657 1780 : memcpy(info->conkey, cachedfk->conkey, sizeof(info->conkey));
658 1780 : memcpy(info->confkey, cachedfk->confkey, sizeof(info->confkey));
659 1780 : memcpy(info->conpfeqop, cachedfk->conpfeqop, sizeof(info->conpfeqop));
660 : /* zero out fields to be filled by match_foreign_keys_to_quals */
661 1780 : info->nmatched_ec = 0;
662 1780 : info->nconst_ec = 0;
663 1780 : info->nmatched_rcols = 0;
664 1780 : info->nmatched_ri = 0;
665 1780 : memset(info->eclass, 0, sizeof(info->eclass));
666 1780 : memset(info->fk_eclass_member, 0, sizeof(info->fk_eclass_member));
667 1780 : memset(info->rinfos, 0, sizeof(info->rinfos));
668 :
669 1780 : root->fkey_list = lappend(root->fkey_list, info);
670 : }
671 : }
672 : }
673 :
674 : /*
675 : * get_relation_notnullatts -
676 : * Retrieves column not-null constraint information for a given relation.
677 : *
678 : * We do this while we have the relcache entry open, and store the column
679 : * not-null constraint information in a hash table based on the relation OID.
680 : */
681 : void
682 511944 : get_relation_notnullatts(PlannerInfo *root, Relation relation)
683 : {
684 511944 : Oid relid = RelationGetRelid(relation);
685 : NotnullHashEntry *hentry;
686 : bool found;
687 511944 : Bitmapset *notnullattnums = NULL;
688 :
689 : /* bail out if the relation has no not-null constraints */
690 511944 : if (relation->rd_att->constr == NULL ||
691 342062 : !relation->rd_att->constr->has_not_null)
692 213302 : return;
693 :
694 : /* create the hash table if it hasn't been created yet */
695 336718 : if (root->glob->rel_notnullatts_hash == NULL)
696 : {
697 : HTAB *hashtab;
698 : HASHCTL hash_ctl;
699 :
700 170788 : hash_ctl.keysize = sizeof(Oid);
701 170788 : hash_ctl.entrysize = sizeof(NotnullHashEntry);
702 170788 : hash_ctl.hcxt = CurrentMemoryContext;
703 :
704 170788 : hashtab = hash_create("Relation NOT NULL attnums",
705 : 64L, /* arbitrary initial size */
706 : &hash_ctl,
707 : HASH_ELEM | HASH_BLOBS | HASH_CONTEXT);
708 :
709 170788 : root->glob->rel_notnullatts_hash = hashtab;
710 : }
711 :
712 : /*
713 : * Create a hash entry for this relation OID, if we don't have one
714 : * already.
715 : */
716 336718 : hentry = (NotnullHashEntry *) hash_search(root->glob->rel_notnullatts_hash,
717 : &relid,
718 : HASH_ENTER,
719 : &found);
720 :
721 : /* bail out if a hash entry already exists for this relation OID */
722 336718 : if (found)
723 38076 : return;
724 :
725 : /* collect the column not-null constraint information for this relation */
726 4462608 : for (int i = 0; i < relation->rd_att->natts; i++)
727 : {
728 4163966 : CompactAttribute *attr = TupleDescCompactAttr(relation->rd_att, i);
729 :
730 : Assert(attr->attnullability != ATTNULLABLE_UNKNOWN);
731 :
732 4163966 : if (attr->attnullability == ATTNULLABLE_VALID)
733 : {
734 3523540 : notnullattnums = bms_add_member(notnullattnums, i + 1);
735 :
736 : /*
737 : * Per RemoveAttributeById(), dropped columns will have their
738 : * attnotnull unset, so we needn't check for dropped columns in
739 : * the above condition.
740 : */
741 : Assert(!attr->attisdropped);
742 : }
743 : }
744 :
745 : /* ... and initialize the new hash entry */
746 298642 : hentry->notnullattnums = notnullattnums;
747 : }
748 :
749 : /*
750 : * find_relation_notnullatts -
751 : * Searches the hash table and returns the column not-null constraint
752 : * information for a given relation.
753 : */
754 : Bitmapset *
755 449164 : find_relation_notnullatts(PlannerInfo *root, Oid relid)
756 : {
757 : NotnullHashEntry *hentry;
758 : bool found;
759 :
760 449164 : if (root->glob->rel_notnullatts_hash == NULL)
761 117464 : return NULL;
762 :
763 331700 : hentry = (NotnullHashEntry *) hash_search(root->glob->rel_notnullatts_hash,
764 : &relid,
765 : HASH_FIND,
766 : &found);
767 331700 : if (!found)
768 5064 : return NULL;
769 :
770 326636 : return hentry->notnullattnums;
771 : }
772 :
773 : /*
774 : * infer_arbiter_indexes -
775 : * Determine the unique indexes used to arbitrate speculative insertion.
776 : *
777 : * Uses user-supplied inference clause expressions and predicate to match a
778 : * unique index from those defined and ready on the heap relation (target).
779 : * An exact match is required on columns/expressions (although they can appear
780 : * in any order). However, the predicate given by the user need only restrict
781 : * insertion to a subset of some part of the table covered by some particular
782 : * unique index (in particular, a partial unique index) in order to be
783 : * inferred.
784 : *
785 : * The implementation does not consider which B-Tree operator class any
786 : * particular available unique index attribute uses, unless one was specified
787 : * in the inference specification. The same is true of collations. In
788 : * particular, there is no system dependency on the default operator class for
789 : * the purposes of inference. If no opclass (or collation) is specified, then
790 : * all matching indexes (that may or may not match the default in terms of
791 : * each attribute opclass/collation) are used for inference.
792 : */
793 : List *
794 1820 : infer_arbiter_indexes(PlannerInfo *root)
795 : {
796 1820 : OnConflictExpr *onconflict = root->parse->onConflict;
797 :
798 : /* Iteration state */
799 : Index varno;
800 : RangeTblEntry *rte;
801 : Relation relation;
802 1820 : Oid indexOidFromConstraint = InvalidOid;
803 : List *indexList;
804 : ListCell *l;
805 :
806 : /* Normalized inference attributes and inference expressions: */
807 1820 : Bitmapset *inferAttrs = NULL;
808 1820 : List *inferElems = NIL;
809 :
810 : /* Results */
811 1820 : List *results = NIL;
812 :
813 : /*
814 : * Quickly return NIL for ON CONFLICT DO NOTHING without an inference
815 : * specification or named constraint. ON CONFLICT DO UPDATE statements
816 : * must always provide one or the other (but parser ought to have caught
817 : * that already).
818 : */
819 1820 : if (onconflict->arbiterElems == NIL &&
820 420 : onconflict->constraint == InvalidOid)
821 228 : return NIL;
822 :
823 : /*
824 : * We need not lock the relation since it was already locked, either by
825 : * the rewriter or when expand_inherited_rtentry() added it to the query's
826 : * rangetable.
827 : */
828 1592 : varno = root->parse->resultRelation;
829 1592 : rte = rt_fetch(varno, root->parse->rtable);
830 :
831 1592 : relation = table_open(rte->relid, NoLock);
832 :
833 : /*
834 : * Build normalized/BMS representation of plain indexed attributes, as
835 : * well as a separate list of expression items. This simplifies matching
836 : * the cataloged definition of indexes.
837 : */
838 3446 : foreach(l, onconflict->arbiterElems)
839 : {
840 1854 : InferenceElem *elem = (InferenceElem *) lfirst(l);
841 : Var *var;
842 : int attno;
843 :
844 1854 : if (!IsA(elem->expr, Var))
845 : {
846 : /* If not a plain Var, just shove it in inferElems for now */
847 174 : inferElems = lappend(inferElems, elem->expr);
848 174 : continue;
849 : }
850 :
851 1680 : var = (Var *) elem->expr;
852 1680 : attno = var->varattno;
853 :
854 1680 : if (attno == 0)
855 0 : ereport(ERROR,
856 : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
857 : errmsg("whole row unique index inference specifications are not supported")));
858 :
859 1680 : inferAttrs = bms_add_member(inferAttrs,
860 : attno - FirstLowInvalidHeapAttributeNumber);
861 : }
862 :
863 : /*
864 : * Lookup named constraint's index. This is not immediately returned
865 : * because some additional sanity checks are required.
866 : */
867 1592 : if (onconflict->constraint != InvalidOid)
868 : {
869 192 : indexOidFromConstraint = get_constraint_index(onconflict->constraint);
870 :
871 192 : if (indexOidFromConstraint == InvalidOid)
872 0 : ereport(ERROR,
873 : (errcode(ERRCODE_WRONG_OBJECT_TYPE),
874 : errmsg("constraint in ON CONFLICT clause has no associated index")));
875 : }
876 :
877 : /*
878 : * Using that representation, iterate through the list of indexes on the
879 : * target relation to try and find a match
880 : */
881 1592 : indexList = RelationGetIndexList(relation);
882 :
883 3420 : foreach(l, indexList)
884 : {
885 2020 : Oid indexoid = lfirst_oid(l);
886 : Relation idxRel;
887 : Form_pg_index idxForm;
888 : Bitmapset *indexedAttrs;
889 : List *idxExprs;
890 : List *predExprs;
891 : AttrNumber natt;
892 : ListCell *el;
893 :
894 : /*
895 : * Extract info from the relation descriptor for the index. Obtain
896 : * the same lock type that the executor will ultimately use.
897 : *
898 : * Let executor complain about !indimmediate case directly, because
899 : * enforcement needs to occur there anyway when an inference clause is
900 : * omitted.
901 : */
902 2020 : idxRel = index_open(indexoid, rte->rellockmode);
903 2020 : idxForm = idxRel->rd_index;
904 :
905 2020 : if (!idxForm->indisvalid)
906 6 : goto next;
907 :
908 : /*
909 : * Note that we do not perform a check against indcheckxmin (like e.g.
910 : * get_relation_info()) here to eliminate candidates, because
911 : * uniqueness checking only cares about the most recently committed
912 : * tuple versions.
913 : */
914 :
915 : /*
916 : * Look for match on "ON constraint_name" variant, which may not be
917 : * unique constraint. This can only be a constraint name.
918 : */
919 2014 : if (indexOidFromConstraint == idxForm->indexrelid)
920 : {
921 192 : if (idxForm->indisexclusion && onconflict->action == ONCONFLICT_UPDATE)
922 78 : ereport(ERROR,
923 : (errcode(ERRCODE_WRONG_OBJECT_TYPE),
924 : errmsg("ON CONFLICT DO UPDATE not supported with exclusion constraints")));
925 :
926 114 : results = lappend_oid(results, idxForm->indexrelid);
927 114 : list_free(indexList);
928 114 : index_close(idxRel, NoLock);
929 114 : table_close(relation, NoLock);
930 114 : return results;
931 : }
932 1822 : else if (indexOidFromConstraint != InvalidOid)
933 : {
934 : /* No point in further work for index in named constraint case */
935 18 : goto next;
936 : }
937 :
938 : /*
939 : * Only considering conventional inference at this point (not named
940 : * constraints), so index under consideration can be immediately
941 : * skipped if it's not unique
942 : */
943 1804 : if (!idxForm->indisunique)
944 4 : goto next;
945 :
946 : /*
947 : * So-called unique constraints with WITHOUT OVERLAPS are really
948 : * exclusion constraints, so skip those too.
949 : */
950 1800 : if (idxForm->indisexclusion)
951 144 : goto next;
952 :
953 : /* Build BMS representation of plain (non expression) index attrs */
954 1656 : indexedAttrs = NULL;
955 3876 : for (natt = 0; natt < idxForm->indnkeyatts; natt++)
956 : {
957 2220 : int attno = idxRel->rd_index->indkey.values[natt];
958 :
959 2220 : if (attno != 0)
960 1908 : indexedAttrs = bms_add_member(indexedAttrs,
961 : attno - FirstLowInvalidHeapAttributeNumber);
962 : }
963 :
964 : /* Non-expression attributes (if any) must match */
965 1656 : if (!bms_equal(indexedAttrs, inferAttrs))
966 378 : goto next;
967 :
968 : /* Expression attributes (if any) must match */
969 1278 : idxExprs = RelationGetIndexExpressions(idxRel);
970 1278 : if (idxExprs && varno != 1)
971 6 : ChangeVarNodes((Node *) idxExprs, 1, varno, 0);
972 :
973 2916 : foreach(el, onconflict->arbiterElems)
974 : {
975 1686 : InferenceElem *elem = (InferenceElem *) lfirst(el);
976 :
977 : /*
978 : * Ensure that collation/opclass aspects of inference expression
979 : * element match. Even though this loop is primarily concerned
980 : * with matching expressions, it is a convenient point to check
981 : * this for both expressions and ordinary (non-expression)
982 : * attributes appearing as inference elements.
983 : */
984 1686 : if (!infer_collation_opclass_match(elem, idxRel, idxExprs))
985 48 : goto next;
986 :
987 : /*
988 : * Plain Vars don't factor into count of expression elements, and
989 : * the question of whether or not they satisfy the index
990 : * definition has already been considered (they must).
991 : */
992 1650 : if (IsA(elem->expr, Var))
993 1476 : continue;
994 :
995 : /*
996 : * Might as well avoid redundant check in the rare cases where
997 : * infer_collation_opclass_match() is required to do real work.
998 : * Otherwise, check that element expression appears in cataloged
999 : * index definition.
1000 : */
1001 174 : if (elem->infercollid != InvalidOid ||
1002 306 : elem->inferopclass != InvalidOid ||
1003 150 : list_member(idxExprs, elem->expr))
1004 162 : continue;
1005 :
1006 12 : goto next;
1007 : }
1008 :
1009 : /*
1010 : * Now that all inference elements were matched, ensure that the
1011 : * expression elements from inference clause are not missing any
1012 : * cataloged expressions. This does the right thing when unique
1013 : * indexes redundantly repeat the same attribute, or if attributes
1014 : * redundantly appear multiple times within an inference clause.
1015 : */
1016 1230 : if (list_difference(idxExprs, inferElems) != NIL)
1017 54 : goto next;
1018 :
1019 : /*
1020 : * If it's a partial index, its predicate must be implied by the ON
1021 : * CONFLICT's WHERE clause.
1022 : */
1023 1176 : predExprs = RelationGetIndexPredicate(idxRel);
1024 1176 : if (predExprs && varno != 1)
1025 6 : ChangeVarNodes((Node *) predExprs, 1, varno, 0);
1026 :
1027 1176 : if (!predicate_implied_by(predExprs, (List *) onconflict->arbiterWhere, false))
1028 36 : goto next;
1029 :
1030 1140 : results = lappend_oid(results, idxForm->indexrelid);
1031 1828 : next:
1032 1828 : index_close(idxRel, NoLock);
1033 : }
1034 :
1035 1400 : list_free(indexList);
1036 1400 : table_close(relation, NoLock);
1037 :
1038 1400 : if (results == NIL)
1039 314 : ereport(ERROR,
1040 : (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
1041 : errmsg("there is no unique or exclusion constraint matching the ON CONFLICT specification")));
1042 :
1043 1086 : return results;
1044 : }
1045 :
1046 : /*
1047 : * infer_collation_opclass_match - ensure infer element opclass/collation match
1048 : *
1049 : * Given unique index inference element from inference specification, if
1050 : * collation was specified, or if opclass was specified, verify that there is
1051 : * at least one matching indexed attribute (occasionally, there may be more).
1052 : * Skip this in the common case where inference specification does not include
1053 : * collation or opclass (instead matching everything, regardless of cataloged
1054 : * collation/opclass of indexed attribute).
1055 : *
1056 : * At least historically, Postgres has not offered collations or opclasses
1057 : * with alternative-to-default notions of equality, so these additional
1058 : * criteria should only be required infrequently.
1059 : *
1060 : * Don't give up immediately when an inference element matches some attribute
1061 : * cataloged as indexed but not matching additional opclass/collation
1062 : * criteria. This is done so that the implementation is as forgiving as
1063 : * possible of redundancy within cataloged index attributes (or, less
1064 : * usefully, within inference specification elements). If collations actually
1065 : * differ between apparently redundantly indexed attributes (redundant within
1066 : * or across indexes), then there really is no redundancy as such.
1067 : *
1068 : * Note that if an inference element specifies an opclass and a collation at
1069 : * once, both must match in at least one particular attribute within index
1070 : * catalog definition in order for that inference element to be considered
1071 : * inferred/satisfied.
1072 : */
1073 : static bool
1074 1686 : infer_collation_opclass_match(InferenceElem *elem, Relation idxRel,
1075 : List *idxExprs)
1076 : {
1077 : AttrNumber natt;
1078 1686 : Oid inferopfamily = InvalidOid; /* OID of opclass opfamily */
1079 1686 : Oid inferopcinputtype = InvalidOid; /* OID of opclass input type */
1080 1686 : int nplain = 0; /* # plain attrs observed */
1081 :
1082 : /*
1083 : * If inference specification element lacks collation/opclass, then no
1084 : * need to check for exact match.
1085 : */
1086 1686 : if (elem->infercollid == InvalidOid && elem->inferopclass == InvalidOid)
1087 1572 : return true;
1088 :
1089 : /*
1090 : * Lookup opfamily and input type, for matching indexes
1091 : */
1092 114 : if (elem->inferopclass)
1093 : {
1094 84 : inferopfamily = get_opclass_family(elem->inferopclass);
1095 84 : inferopcinputtype = get_opclass_input_type(elem->inferopclass);
1096 : }
1097 :
1098 246 : for (natt = 1; natt <= idxRel->rd_att->natts; natt++)
1099 : {
1100 210 : Oid opfamily = idxRel->rd_opfamily[natt - 1];
1101 210 : Oid opcinputtype = idxRel->rd_opcintype[natt - 1];
1102 210 : Oid collation = idxRel->rd_indcollation[natt - 1];
1103 210 : int attno = idxRel->rd_index->indkey.values[natt - 1];
1104 :
1105 210 : if (attno != 0)
1106 168 : nplain++;
1107 :
1108 210 : if (elem->inferopclass != InvalidOid &&
1109 66 : (inferopfamily != opfamily || inferopcinputtype != opcinputtype))
1110 : {
1111 : /* Attribute needed to match opclass, but didn't */
1112 90 : continue;
1113 : }
1114 :
1115 120 : if (elem->infercollid != InvalidOid &&
1116 84 : elem->infercollid != collation)
1117 : {
1118 : /* Attribute needed to match collation, but didn't */
1119 36 : continue;
1120 : }
1121 :
1122 : /* If one matching index att found, good enough -- return true */
1123 84 : if (IsA(elem->expr, Var))
1124 : {
1125 54 : if (((Var *) elem->expr)->varattno == attno)
1126 54 : return true;
1127 : }
1128 30 : else if (attno == 0)
1129 : {
1130 30 : Node *nattExpr = list_nth(idxExprs, (natt - 1) - nplain);
1131 :
1132 : /*
1133 : * Note that unlike routines like match_index_to_operand() we
1134 : * don't need to care about RelabelType. Neither the index
1135 : * definition nor the inference clause should contain them.
1136 : */
1137 30 : if (equal(elem->expr, nattExpr))
1138 24 : return true;
1139 : }
1140 : }
1141 :
1142 36 : return false;
1143 : }
1144 :
1145 : /*
1146 : * estimate_rel_size - estimate # pages and # tuples in a table or index
1147 : *
1148 : * We also estimate the fraction of the pages that are marked all-visible in
1149 : * the visibility map, for use in estimation of index-only scans.
1150 : *
1151 : * If attr_widths isn't NULL, it points to the zero-index entry of the
1152 : * relation's attr_widths[] cache; we fill this in if we have need to compute
1153 : * the attribute widths for estimation purposes.
1154 : */
1155 : void
1156 452070 : estimate_rel_size(Relation rel, int32 *attr_widths,
1157 : BlockNumber *pages, double *tuples, double *allvisfrac)
1158 : {
1159 : BlockNumber curpages;
1160 : BlockNumber relpages;
1161 : double reltuples;
1162 : BlockNumber relallvisible;
1163 : double density;
1164 :
1165 452070 : if (RELKIND_HAS_TABLE_AM(rel->rd_rel->relkind))
1166 : {
1167 448554 : table_relation_estimate_size(rel, attr_widths, pages, tuples,
1168 : allvisfrac);
1169 : }
1170 3516 : else if (rel->rd_rel->relkind == RELKIND_INDEX)
1171 : {
1172 : /*
1173 : * XXX: It'd probably be good to move this into a callback, individual
1174 : * index types e.g. know if they have a metapage.
1175 : */
1176 :
1177 : /* it has storage, ok to call the smgr */
1178 984 : curpages = RelationGetNumberOfBlocks(rel);
1179 :
1180 : /* report estimated # pages */
1181 984 : *pages = curpages;
1182 : /* quick exit if rel is clearly empty */
1183 984 : if (curpages == 0)
1184 : {
1185 0 : *tuples = 0;
1186 0 : *allvisfrac = 0;
1187 0 : return;
1188 : }
1189 :
1190 : /* coerce values in pg_class to more desirable types */
1191 984 : relpages = (BlockNumber) rel->rd_rel->relpages;
1192 984 : reltuples = (double) rel->rd_rel->reltuples;
1193 984 : relallvisible = (BlockNumber) rel->rd_rel->relallvisible;
1194 :
1195 : /*
1196 : * Discount the metapage while estimating the number of tuples. This
1197 : * is a kluge because it assumes more than it ought to about index
1198 : * structure. Currently it's OK for btree, hash, and GIN indexes but
1199 : * suspect for GiST indexes.
1200 : */
1201 984 : if (relpages > 0)
1202 : {
1203 966 : curpages--;
1204 966 : relpages--;
1205 : }
1206 :
1207 : /* estimate number of tuples from previous tuple density */
1208 984 : if (reltuples >= 0 && relpages > 0)
1209 666 : density = reltuples / (double) relpages;
1210 : else
1211 : {
1212 : /*
1213 : * If we have no data because the relation was never vacuumed,
1214 : * estimate tuple width from attribute datatypes. We assume here
1215 : * that the pages are completely full, which is OK for tables
1216 : * (since they've presumably not been VACUUMed yet) but is
1217 : * probably an overestimate for indexes. Fortunately
1218 : * get_relation_info() can clamp the overestimate to the parent
1219 : * table's size.
1220 : *
1221 : * Note: this code intentionally disregards alignment
1222 : * considerations, because (a) that would be gilding the lily
1223 : * considering how crude the estimate is, and (b) it creates
1224 : * platform dependencies in the default plans which are kind of a
1225 : * headache for regression testing.
1226 : *
1227 : * XXX: Should this logic be more index specific?
1228 : */
1229 : int32 tuple_width;
1230 :
1231 318 : tuple_width = get_rel_data_width(rel, attr_widths);
1232 318 : tuple_width += MAXALIGN(SizeofHeapTupleHeader);
1233 318 : tuple_width += sizeof(ItemIdData);
1234 : /* note: integer division is intentional here */
1235 318 : density = (BLCKSZ - SizeOfPageHeaderData) / tuple_width;
1236 : }
1237 984 : *tuples = rint(density * (double) curpages);
1238 :
1239 : /*
1240 : * We use relallvisible as-is, rather than scaling it up like we do
1241 : * for the pages and tuples counts, on the theory that any pages added
1242 : * since the last VACUUM are most likely not marked all-visible. But
1243 : * costsize.c wants it converted to a fraction.
1244 : */
1245 984 : if (relallvisible == 0 || curpages <= 0)
1246 984 : *allvisfrac = 0;
1247 0 : else if ((double) relallvisible >= curpages)
1248 0 : *allvisfrac = 1;
1249 : else
1250 0 : *allvisfrac = (double) relallvisible / curpages;
1251 : }
1252 : else
1253 : {
1254 : /*
1255 : * Just use whatever's in pg_class. This covers foreign tables,
1256 : * sequences, and also relkinds without storage (shouldn't get here?);
1257 : * see initializations in AddNewRelationTuple(). Note that FDW must
1258 : * cope if reltuples is -1!
1259 : */
1260 2532 : *pages = rel->rd_rel->relpages;
1261 2532 : *tuples = rel->rd_rel->reltuples;
1262 2532 : *allvisfrac = 0;
1263 : }
1264 : }
1265 :
1266 :
1267 : /*
1268 : * get_rel_data_width
1269 : *
1270 : * Estimate the average width of (the data part of) the relation's tuples.
1271 : *
1272 : * If attr_widths isn't NULL, it points to the zero-index entry of the
1273 : * relation's attr_widths[] cache; use and update that cache as appropriate.
1274 : *
1275 : * Currently we ignore dropped columns. Ideally those should be included
1276 : * in the result, but we haven't got any way to get info about them; and
1277 : * since they might be mostly NULLs, treating them as zero-width is not
1278 : * necessarily the wrong thing anyway.
1279 : */
1280 : int32
1281 150930 : get_rel_data_width(Relation rel, int32 *attr_widths)
1282 : {
1283 150930 : int64 tuple_width = 0;
1284 : int i;
1285 :
1286 817850 : for (i = 1; i <= RelationGetNumberOfAttributes(rel); i++)
1287 : {
1288 666920 : Form_pg_attribute att = TupleDescAttr(rel->rd_att, i - 1);
1289 : int32 item_width;
1290 :
1291 666920 : if (att->attisdropped)
1292 2660 : continue;
1293 :
1294 : /* use previously cached data, if any */
1295 664260 : if (attr_widths != NULL && attr_widths[i] > 0)
1296 : {
1297 5812 : tuple_width += attr_widths[i];
1298 5812 : continue;
1299 : }
1300 :
1301 : /* This should match set_rel_width() in costsize.c */
1302 658448 : item_width = get_attavgwidth(RelationGetRelid(rel), i);
1303 658448 : if (item_width <= 0)
1304 : {
1305 656600 : item_width = get_typavgwidth(att->atttypid, att->atttypmod);
1306 : Assert(item_width > 0);
1307 : }
1308 658448 : if (attr_widths != NULL)
1309 583838 : attr_widths[i] = item_width;
1310 658448 : tuple_width += item_width;
1311 : }
1312 :
1313 150930 : return clamp_width_est(tuple_width);
1314 : }
1315 :
1316 : /*
1317 : * get_relation_data_width
1318 : *
1319 : * External API for get_rel_data_width: same behavior except we have to
1320 : * open the relcache entry.
1321 : */
1322 : int32
1323 2516 : get_relation_data_width(Oid relid, int32 *attr_widths)
1324 : {
1325 : int32 result;
1326 : Relation relation;
1327 :
1328 : /* As above, assume relation is already locked */
1329 2516 : relation = table_open(relid, NoLock);
1330 :
1331 2516 : result = get_rel_data_width(relation, attr_widths);
1332 :
1333 2516 : table_close(relation, NoLock);
1334 :
1335 2516 : return result;
1336 : }
1337 :
1338 :
1339 : /*
1340 : * get_relation_constraints
1341 : *
1342 : * Retrieve the applicable constraint expressions of the given relation.
1343 : * Only constraints that have been validated are considered.
1344 : *
1345 : * Returns a List (possibly empty) of constraint expressions. Each one
1346 : * has been canonicalized, and its Vars are changed to have the varno
1347 : * indicated by rel->relid. This allows the expressions to be easily
1348 : * compared to expressions taken from WHERE.
1349 : *
1350 : * If include_noinherit is true, it's okay to include constraints that
1351 : * are marked NO INHERIT.
1352 : *
1353 : * If include_notnull is true, "col IS NOT NULL" expressions are generated
1354 : * and added to the result for each column that's marked attnotnull.
1355 : *
1356 : * If include_partition is true, and the relation is a partition,
1357 : * also include the partitioning constraints.
1358 : *
1359 : * Note: at present this is invoked at most once per relation per planner
1360 : * run, and in many cases it won't be invoked at all, so there seems no
1361 : * point in caching the data in RelOptInfo.
1362 : */
1363 : static List *
1364 21318 : get_relation_constraints(PlannerInfo *root,
1365 : Oid relationObjectId, RelOptInfo *rel,
1366 : bool include_noinherit,
1367 : bool include_notnull,
1368 : bool include_partition)
1369 : {
1370 21318 : List *result = NIL;
1371 21318 : Index varno = rel->relid;
1372 : Relation relation;
1373 : TupleConstr *constr;
1374 :
1375 : /*
1376 : * We assume the relation has already been safely locked.
1377 : */
1378 21318 : relation = table_open(relationObjectId, NoLock);
1379 :
1380 21318 : constr = relation->rd_att->constr;
1381 21318 : if (constr != NULL)
1382 : {
1383 8040 : int num_check = constr->num_check;
1384 : int i;
1385 :
1386 8620 : for (i = 0; i < num_check; i++)
1387 : {
1388 : Node *cexpr;
1389 :
1390 : /*
1391 : * If this constraint hasn't been fully validated yet, we must
1392 : * ignore it here.
1393 : */
1394 580 : if (!constr->check[i].ccvalid)
1395 54 : continue;
1396 :
1397 : /*
1398 : * NOT ENFORCED constraints are always marked as invalid, which
1399 : * should have been ignored.
1400 : */
1401 : Assert(constr->check[i].ccenforced);
1402 :
1403 : /*
1404 : * Also ignore if NO INHERIT and we weren't told that that's safe.
1405 : */
1406 526 : if (constr->check[i].ccnoinherit && !include_noinherit)
1407 0 : continue;
1408 :
1409 526 : cexpr = stringToNode(constr->check[i].ccbin);
1410 :
1411 : /*
1412 : * Fix Vars to have the desired varno. This must be done before
1413 : * const-simplification because eval_const_expressions reduces
1414 : * NullTest for Vars based on varno.
1415 : */
1416 526 : if (varno != 1)
1417 502 : ChangeVarNodes(cexpr, 1, varno, 0);
1418 :
1419 : /*
1420 : * Run each expression through const-simplification and
1421 : * canonicalization. This is not just an optimization, but is
1422 : * necessary, because we will be comparing it to
1423 : * similarly-processed qual clauses, and may fail to detect valid
1424 : * matches without this. This must match the processing done to
1425 : * qual clauses in preprocess_expression()! (We can skip the
1426 : * stuff involving subqueries, however, since we don't allow any
1427 : * in check constraints.)
1428 : */
1429 526 : cexpr = eval_const_expressions(root, cexpr);
1430 :
1431 526 : cexpr = (Node *) canonicalize_qual((Expr *) cexpr, true);
1432 :
1433 : /*
1434 : * Finally, convert to implicit-AND format (that is, a List) and
1435 : * append the resulting item(s) to our output list.
1436 : */
1437 526 : result = list_concat(result,
1438 526 : make_ands_implicit((Expr *) cexpr));
1439 : }
1440 :
1441 : /* Add NOT NULL constraints in expression form, if requested */
1442 8040 : if (include_notnull && constr->has_not_null)
1443 : {
1444 7596 : int natts = relation->rd_att->natts;
1445 :
1446 30858 : for (i = 1; i <= natts; i++)
1447 : {
1448 23262 : CompactAttribute *att = TupleDescCompactAttr(relation->rd_att, i - 1);
1449 :
1450 23262 : if (att->attnullability == ATTNULLABLE_VALID && !att->attisdropped)
1451 : {
1452 9374 : Form_pg_attribute wholeatt = TupleDescAttr(relation->rd_att, i - 1);
1453 9374 : NullTest *ntest = makeNode(NullTest);
1454 :
1455 9374 : ntest->arg = (Expr *) makeVar(varno,
1456 : i,
1457 : wholeatt->atttypid,
1458 : wholeatt->atttypmod,
1459 : wholeatt->attcollation,
1460 : 0);
1461 9374 : ntest->nulltesttype = IS_NOT_NULL;
1462 :
1463 : /*
1464 : * argisrow=false is correct even for a composite column,
1465 : * because attnotnull does not represent a SQL-spec IS NOT
1466 : * NULL test in such a case, just IS DISTINCT FROM NULL.
1467 : */
1468 9374 : ntest->argisrow = false;
1469 9374 : ntest->location = -1;
1470 9374 : result = lappend(result, ntest);
1471 : }
1472 : }
1473 : }
1474 : }
1475 :
1476 : /*
1477 : * Add partitioning constraints, if requested.
1478 : */
1479 21318 : if (include_partition && relation->rd_rel->relispartition)
1480 : {
1481 : /* make sure rel->partition_qual is set */
1482 12 : set_baserel_partition_constraint(relation, rel);
1483 12 : result = list_concat(result, rel->partition_qual);
1484 : }
1485 :
1486 : /*
1487 : * Expand virtual generated columns in the constraint expressions.
1488 : */
1489 21318 : if (result)
1490 7778 : result = (List *) expand_generated_columns_in_expr((Node *) result,
1491 : relation,
1492 : varno);
1493 :
1494 21318 : table_close(relation, NoLock);
1495 :
1496 21318 : return result;
1497 : }
1498 :
1499 : /*
1500 : * Try loading data for the statistics object.
1501 : *
1502 : * We don't know if the data (specified by statOid and inh value) exist.
1503 : * The result is stored in stainfos list.
1504 : */
1505 : static void
1506 4012 : get_relation_statistics_worker(List **stainfos, RelOptInfo *rel,
1507 : Oid statOid, bool inh,
1508 : Bitmapset *keys, List *exprs)
1509 : {
1510 : Form_pg_statistic_ext_data dataForm;
1511 : HeapTuple dtup;
1512 :
1513 4012 : dtup = SearchSysCache2(STATEXTDATASTXOID,
1514 : ObjectIdGetDatum(statOid), BoolGetDatum(inh));
1515 4012 : if (!HeapTupleIsValid(dtup))
1516 2008 : return;
1517 :
1518 2004 : dataForm = (Form_pg_statistic_ext_data) GETSTRUCT(dtup);
1519 :
1520 : /* add one StatisticExtInfo for each kind built */
1521 2004 : if (statext_is_kind_built(dtup, STATS_EXT_NDISTINCT))
1522 : {
1523 714 : StatisticExtInfo *info = makeNode(StatisticExtInfo);
1524 :
1525 714 : info->statOid = statOid;
1526 714 : info->inherit = dataForm->stxdinherit;
1527 714 : info->rel = rel;
1528 714 : info->kind = STATS_EXT_NDISTINCT;
1529 714 : info->keys = bms_copy(keys);
1530 714 : info->exprs = exprs;
1531 :
1532 714 : *stainfos = lappend(*stainfos, info);
1533 : }
1534 :
1535 2004 : if (statext_is_kind_built(dtup, STATS_EXT_DEPENDENCIES))
1536 : {
1537 528 : StatisticExtInfo *info = makeNode(StatisticExtInfo);
1538 :
1539 528 : info->statOid = statOid;
1540 528 : info->inherit = dataForm->stxdinherit;
1541 528 : info->rel = rel;
1542 528 : info->kind = STATS_EXT_DEPENDENCIES;
1543 528 : info->keys = bms_copy(keys);
1544 528 : info->exprs = exprs;
1545 :
1546 528 : *stainfos = lappend(*stainfos, info);
1547 : }
1548 :
1549 2004 : if (statext_is_kind_built(dtup, STATS_EXT_MCV))
1550 : {
1551 882 : StatisticExtInfo *info = makeNode(StatisticExtInfo);
1552 :
1553 882 : info->statOid = statOid;
1554 882 : info->inherit = dataForm->stxdinherit;
1555 882 : info->rel = rel;
1556 882 : info->kind = STATS_EXT_MCV;
1557 882 : info->keys = bms_copy(keys);
1558 882 : info->exprs = exprs;
1559 :
1560 882 : *stainfos = lappend(*stainfos, info);
1561 : }
1562 :
1563 2004 : if (statext_is_kind_built(dtup, STATS_EXT_EXPRESSIONS))
1564 : {
1565 810 : StatisticExtInfo *info = makeNode(StatisticExtInfo);
1566 :
1567 810 : info->statOid = statOid;
1568 810 : info->inherit = dataForm->stxdinherit;
1569 810 : info->rel = rel;
1570 810 : info->kind = STATS_EXT_EXPRESSIONS;
1571 810 : info->keys = bms_copy(keys);
1572 810 : info->exprs = exprs;
1573 :
1574 810 : *stainfos = lappend(*stainfos, info);
1575 : }
1576 :
1577 2004 : ReleaseSysCache(dtup);
1578 : }
1579 :
1580 : /*
1581 : * get_relation_statistics
1582 : * Retrieve extended statistics defined on the table.
1583 : *
1584 : * Returns a List (possibly empty) of StatisticExtInfo objects describing
1585 : * the statistics. Note that this doesn't load the actual statistics data,
1586 : * just the identifying metadata. Only stats actually built are considered.
1587 : */
1588 : static List *
1589 472746 : get_relation_statistics(PlannerInfo *root, RelOptInfo *rel,
1590 : Relation relation)
1591 : {
1592 472746 : Index varno = rel->relid;
1593 : List *statoidlist;
1594 472746 : List *stainfos = NIL;
1595 : ListCell *l;
1596 :
1597 472746 : statoidlist = RelationGetStatExtList(relation);
1598 :
1599 474752 : foreach(l, statoidlist)
1600 : {
1601 2006 : Oid statOid = lfirst_oid(l);
1602 : Form_pg_statistic_ext staForm;
1603 : HeapTuple htup;
1604 2006 : Bitmapset *keys = NULL;
1605 2006 : List *exprs = NIL;
1606 : int i;
1607 :
1608 2006 : htup = SearchSysCache1(STATEXTOID, ObjectIdGetDatum(statOid));
1609 2006 : if (!HeapTupleIsValid(htup))
1610 0 : elog(ERROR, "cache lookup failed for statistics object %u", statOid);
1611 2006 : staForm = (Form_pg_statistic_ext) GETSTRUCT(htup);
1612 :
1613 : /*
1614 : * First, build the array of columns covered. This is ultimately
1615 : * wasted if no stats within the object have actually been built, but
1616 : * it doesn't seem worth troubling over that case.
1617 : */
1618 5698 : for (i = 0; i < staForm->stxkeys.dim1; i++)
1619 3692 : keys = bms_add_member(keys, staForm->stxkeys.values[i]);
1620 :
1621 : /*
1622 : * Preprocess expressions (if any). We read the expressions, fix the
1623 : * varnos, and run them through eval_const_expressions.
1624 : *
1625 : * XXX We don't know yet if there are any data for this stats object,
1626 : * with either stxdinherit value. But it's reasonable to assume there
1627 : * is at least one of those, possibly both. So it's better to process
1628 : * keys and expressions here.
1629 : */
1630 : {
1631 : bool isnull;
1632 : Datum datum;
1633 :
1634 : /* decode expression (if any) */
1635 2006 : datum = SysCacheGetAttr(STATEXTOID, htup,
1636 : Anum_pg_statistic_ext_stxexprs, &isnull);
1637 :
1638 2006 : if (!isnull)
1639 : {
1640 : char *exprsString;
1641 :
1642 814 : exprsString = TextDatumGetCString(datum);
1643 814 : exprs = (List *) stringToNode(exprsString);
1644 814 : pfree(exprsString);
1645 :
1646 : /*
1647 : * Modify the copies we obtain from the relcache to have the
1648 : * correct varno for the parent relation, so that they match
1649 : * up correctly against qual clauses.
1650 : *
1651 : * This must be done before const-simplification because
1652 : * eval_const_expressions reduces NullTest for Vars based on
1653 : * varno.
1654 : */
1655 814 : if (varno != 1)
1656 0 : ChangeVarNodes((Node *) exprs, 1, varno, 0);
1657 :
1658 : /*
1659 : * Run the expressions through eval_const_expressions. This is
1660 : * not just an optimization, but is necessary, because the
1661 : * planner will be comparing them to similarly-processed qual
1662 : * clauses, and may fail to detect valid matches without this.
1663 : * We must not use canonicalize_qual, however, since these
1664 : * aren't qual expressions.
1665 : */
1666 814 : exprs = (List *) eval_const_expressions(root, (Node *) exprs);
1667 :
1668 : /* May as well fix opfuncids too */
1669 814 : fix_opfuncids((Node *) exprs);
1670 : }
1671 : }
1672 :
1673 : /* extract statistics for possible values of stxdinherit flag */
1674 :
1675 2006 : get_relation_statistics_worker(&stainfos, rel, statOid, true, keys, exprs);
1676 :
1677 2006 : get_relation_statistics_worker(&stainfos, rel, statOid, false, keys, exprs);
1678 :
1679 2006 : ReleaseSysCache(htup);
1680 2006 : bms_free(keys);
1681 : }
1682 :
1683 472746 : list_free(statoidlist);
1684 :
1685 472746 : return stainfos;
1686 : }
1687 :
1688 : /*
1689 : * relation_excluded_by_constraints
1690 : *
1691 : * Detect whether the relation need not be scanned because it has either
1692 : * self-inconsistent restrictions, or restrictions inconsistent with the
1693 : * relation's applicable constraints.
1694 : *
1695 : * Note: this examines only rel->relid, rel->reloptkind, and
1696 : * rel->baserestrictinfo; therefore it can be called before filling in
1697 : * other fields of the RelOptInfo.
1698 : */
1699 : bool
1700 517690 : relation_excluded_by_constraints(PlannerInfo *root,
1701 : RelOptInfo *rel, RangeTblEntry *rte)
1702 : {
1703 : bool include_noinherit;
1704 : bool include_notnull;
1705 517690 : bool include_partition = false;
1706 : List *safe_restrictions;
1707 : List *constraint_pred;
1708 : List *safe_constraints;
1709 : ListCell *lc;
1710 :
1711 : /* As of now, constraint exclusion works only with simple relations. */
1712 : Assert(IS_SIMPLE_REL(rel));
1713 :
1714 : /*
1715 : * If there are no base restriction clauses, we have no hope of proving
1716 : * anything below, so fall out quickly.
1717 : */
1718 517690 : if (rel->baserestrictinfo == NIL)
1719 235164 : return false;
1720 :
1721 : /*
1722 : * Regardless of the setting of constraint_exclusion, detect
1723 : * constant-FALSE-or-NULL restriction clauses. Although const-folding
1724 : * will reduce "anything AND FALSE" to just "FALSE", the baserestrictinfo
1725 : * list can still have other members besides the FALSE constant, due to
1726 : * qual pushdown and other mechanisms; so check them all. This doesn't
1727 : * fire very often, but it seems cheap enough to be worth doing anyway.
1728 : * (Without this, we'd miss some optimizations that 9.5 and earlier found
1729 : * via much more roundabout methods.)
1730 : */
1731 705536 : foreach(lc, rel->baserestrictinfo)
1732 : {
1733 423482 : RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
1734 423482 : Expr *clause = rinfo->clause;
1735 :
1736 423482 : if (clause && IsA(clause, Const) &&
1737 472 : (((Const *) clause)->constisnull ||
1738 466 : !DatumGetBool(((Const *) clause)->constvalue)))
1739 472 : return true;
1740 : }
1741 :
1742 : /*
1743 : * Skip further tests, depending on constraint_exclusion.
1744 : */
1745 282054 : switch (constraint_exclusion)
1746 : {
1747 54 : case CONSTRAINT_EXCLUSION_OFF:
1748 : /* In 'off' mode, never make any further tests */
1749 54 : return false;
1750 :
1751 281856 : case CONSTRAINT_EXCLUSION_PARTITION:
1752 :
1753 : /*
1754 : * When constraint_exclusion is set to 'partition' we only handle
1755 : * appendrel members. Partition pruning has already been applied,
1756 : * so there is no need to consider the rel's partition constraints
1757 : * here.
1758 : */
1759 281856 : if (rel->reloptkind == RELOPT_OTHER_MEMBER_REL)
1760 21532 : break; /* appendrel member, so process it */
1761 260324 : return false;
1762 :
1763 144 : case CONSTRAINT_EXCLUSION_ON:
1764 :
1765 : /*
1766 : * In 'on' mode, always apply constraint exclusion. If we are
1767 : * considering a baserel that is a partition (i.e., it was
1768 : * directly named rather than expanded from a parent table), then
1769 : * its partition constraints haven't been considered yet, so
1770 : * include them in the processing here.
1771 : */
1772 144 : if (rel->reloptkind == RELOPT_BASEREL)
1773 114 : include_partition = true;
1774 144 : break; /* always try to exclude */
1775 : }
1776 :
1777 : /*
1778 : * Check for self-contradictory restriction clauses. We dare not make
1779 : * deductions with non-immutable functions, but any immutable clauses that
1780 : * are self-contradictory allow us to conclude the scan is unnecessary.
1781 : *
1782 : * Note: strip off RestrictInfo because predicate_refuted_by() isn't
1783 : * expecting to see any in its predicate argument.
1784 : */
1785 21676 : safe_restrictions = NIL;
1786 51180 : foreach(lc, rel->baserestrictinfo)
1787 : {
1788 29504 : RestrictInfo *rinfo = (RestrictInfo *) lfirst(lc);
1789 :
1790 29504 : if (!contain_mutable_functions((Node *) rinfo->clause))
1791 27964 : safe_restrictions = lappend(safe_restrictions, rinfo->clause);
1792 : }
1793 :
1794 : /*
1795 : * We can use weak refutation here, since we're comparing restriction
1796 : * clauses with restriction clauses.
1797 : */
1798 21676 : if (predicate_refuted_by(safe_restrictions, safe_restrictions, true))
1799 72 : return true;
1800 :
1801 : /*
1802 : * Only plain relations have constraints, so stop here for other rtekinds.
1803 : */
1804 21604 : if (rte->rtekind != RTE_RELATION)
1805 286 : return false;
1806 :
1807 : /*
1808 : * If we are scanning just this table, we can use NO INHERIT constraints,
1809 : * but not if we're scanning its children too. (Note that partitioned
1810 : * tables should never have NO INHERIT constraints; but it's not necessary
1811 : * for us to assume that here.)
1812 : */
1813 21318 : include_noinherit = !rte->inh;
1814 :
1815 : /*
1816 : * Currently, attnotnull constraints must be treated as NO INHERIT unless
1817 : * this is a partitioned table. In future we might track their
1818 : * inheritance status more accurately, allowing this to be refined.
1819 : *
1820 : * XXX do we need/want to change this?
1821 : */
1822 21318 : include_notnull = (!rte->inh || rte->relkind == RELKIND_PARTITIONED_TABLE);
1823 :
1824 : /*
1825 : * Fetch the appropriate set of constraint expressions.
1826 : */
1827 21318 : constraint_pred = get_relation_constraints(root, rte->relid, rel,
1828 : include_noinherit,
1829 : include_notnull,
1830 : include_partition);
1831 :
1832 : /*
1833 : * We do not currently enforce that CHECK constraints contain only
1834 : * immutable functions, so it's necessary to check here. We daren't draw
1835 : * conclusions from plan-time evaluation of non-immutable functions. Since
1836 : * they're ANDed, we can just ignore any mutable constraints in the list,
1837 : * and reason about the rest.
1838 : */
1839 21318 : safe_constraints = NIL;
1840 31420 : foreach(lc, constraint_pred)
1841 : {
1842 10102 : Node *pred = (Node *) lfirst(lc);
1843 :
1844 10102 : if (!contain_mutable_functions(pred))
1845 10102 : safe_constraints = lappend(safe_constraints, pred);
1846 : }
1847 :
1848 : /*
1849 : * The constraints are effectively ANDed together, so we can just try to
1850 : * refute the entire collection at once. This may allow us to make proofs
1851 : * that would fail if we took them individually.
1852 : *
1853 : * Note: we use rel->baserestrictinfo, not safe_restrictions as might seem
1854 : * an obvious optimization. Some of the clauses might be OR clauses that
1855 : * have volatile and nonvolatile subclauses, and it's OK to make
1856 : * deductions with the nonvolatile parts.
1857 : *
1858 : * We need strong refutation because we have to prove that the constraints
1859 : * would yield false, not just NULL.
1860 : */
1861 21318 : if (predicate_refuted_by(safe_constraints, rel->baserestrictinfo, false))
1862 192 : return true;
1863 :
1864 21126 : return false;
1865 : }
1866 :
1867 :
1868 : /*
1869 : * build_physical_tlist
1870 : *
1871 : * Build a targetlist consisting of exactly the relation's user attributes,
1872 : * in order. The executor can special-case such tlists to avoid a projection
1873 : * step at runtime, so we use such tlists preferentially for scan nodes.
1874 : *
1875 : * Exception: if there are any dropped or missing columns, we punt and return
1876 : * NIL. Ideally we would like to handle these cases too. However this
1877 : * creates problems for ExecTypeFromTL, which may be asked to build a tupdesc
1878 : * for a tlist that includes vars of no-longer-existent types. In theory we
1879 : * could dig out the required info from the pg_attribute entries of the
1880 : * relation, but that data is not readily available to ExecTypeFromTL.
1881 : * For now, we don't apply the physical-tlist optimization when there are
1882 : * dropped cols.
1883 : *
1884 : * We also support building a "physical" tlist for subqueries, functions,
1885 : * values lists, table expressions, and CTEs, since the same optimization can
1886 : * occur in SubqueryScan, FunctionScan, ValuesScan, CteScan, TableFunc,
1887 : * NamedTuplestoreScan, and WorkTableScan nodes.
1888 : */
1889 : List *
1890 186826 : build_physical_tlist(PlannerInfo *root, RelOptInfo *rel)
1891 : {
1892 186826 : List *tlist = NIL;
1893 186826 : Index varno = rel->relid;
1894 186826 : RangeTblEntry *rte = planner_rt_fetch(varno, root);
1895 : Relation relation;
1896 : Query *subquery;
1897 : Var *var;
1898 : ListCell *l;
1899 : int attrno,
1900 : numattrs;
1901 : List *colvars;
1902 :
1903 186826 : switch (rte->rtekind)
1904 : {
1905 160552 : case RTE_RELATION:
1906 : /* Assume we already have adequate lock */
1907 160552 : relation = table_open(rte->relid, NoLock);
1908 :
1909 160552 : numattrs = RelationGetNumberOfAttributes(relation);
1910 2834564 : for (attrno = 1; attrno <= numattrs; attrno++)
1911 : {
1912 2674150 : Form_pg_attribute att_tup = TupleDescAttr(relation->rd_att,
1913 : attrno - 1);
1914 :
1915 2674150 : if (att_tup->attisdropped || att_tup->atthasmissing)
1916 : {
1917 : /* found a dropped or missing col, so punt */
1918 138 : tlist = NIL;
1919 138 : break;
1920 : }
1921 :
1922 2674012 : var = makeVar(varno,
1923 : attrno,
1924 : att_tup->atttypid,
1925 : att_tup->atttypmod,
1926 : att_tup->attcollation,
1927 : 0);
1928 :
1929 2674012 : tlist = lappend(tlist,
1930 2674012 : makeTargetEntry((Expr *) var,
1931 : attrno,
1932 : NULL,
1933 : false));
1934 : }
1935 :
1936 160552 : table_close(relation, NoLock);
1937 160552 : break;
1938 :
1939 2346 : case RTE_SUBQUERY:
1940 2346 : subquery = rte->subquery;
1941 8754 : foreach(l, subquery->targetList)
1942 : {
1943 6408 : TargetEntry *tle = (TargetEntry *) lfirst(l);
1944 :
1945 : /*
1946 : * A resjunk column of the subquery can be reflected as
1947 : * resjunk in the physical tlist; we need not punt.
1948 : */
1949 6408 : var = makeVarFromTargetEntry(varno, tle);
1950 :
1951 6408 : tlist = lappend(tlist,
1952 6408 : makeTargetEntry((Expr *) var,
1953 6408 : tle->resno,
1954 : NULL,
1955 6408 : tle->resjunk));
1956 : }
1957 2346 : break;
1958 :
1959 23928 : case RTE_FUNCTION:
1960 : case RTE_TABLEFUNC:
1961 : case RTE_VALUES:
1962 : case RTE_CTE:
1963 : case RTE_NAMEDTUPLESTORE:
1964 : case RTE_RESULT:
1965 : /* Not all of these can have dropped cols, but share code anyway */
1966 23928 : expandRTE(rte, varno, 0, VAR_RETURNING_DEFAULT, -1,
1967 : true /* include dropped */ , NULL, &colvars);
1968 122010 : foreach(l, colvars)
1969 : {
1970 98082 : var = (Var *) lfirst(l);
1971 :
1972 : /*
1973 : * A non-Var in expandRTE's output means a dropped column;
1974 : * must punt.
1975 : */
1976 98082 : if (!IsA(var, Var))
1977 : {
1978 0 : tlist = NIL;
1979 0 : break;
1980 : }
1981 :
1982 98082 : tlist = lappend(tlist,
1983 98082 : makeTargetEntry((Expr *) var,
1984 98082 : var->varattno,
1985 : NULL,
1986 : false));
1987 : }
1988 23928 : break;
1989 :
1990 0 : default:
1991 : /* caller error */
1992 0 : elog(ERROR, "unsupported RTE kind %d in build_physical_tlist",
1993 : (int) rte->rtekind);
1994 : break;
1995 : }
1996 :
1997 186826 : return tlist;
1998 : }
1999 :
2000 : /*
2001 : * build_index_tlist
2002 : *
2003 : * Build a targetlist representing the columns of the specified index.
2004 : * Each column is represented by a Var for the corresponding base-relation
2005 : * column, or an expression in base-relation Vars, as appropriate.
2006 : *
2007 : * There are never any dropped columns in indexes, so unlike
2008 : * build_physical_tlist, we need no failure case.
2009 : */
2010 : static List *
2011 743378 : build_index_tlist(PlannerInfo *root, IndexOptInfo *index,
2012 : Relation heapRelation)
2013 : {
2014 743378 : List *tlist = NIL;
2015 743378 : Index varno = index->rel->relid;
2016 : ListCell *indexpr_item;
2017 : int i;
2018 :
2019 743378 : indexpr_item = list_head(index->indexprs);
2020 2146634 : for (i = 0; i < index->ncolumns; i++)
2021 : {
2022 1403256 : int indexkey = index->indexkeys[i];
2023 : Expr *indexvar;
2024 :
2025 1403256 : if (indexkey != 0)
2026 : {
2027 : /* simple column */
2028 : const FormData_pg_attribute *att_tup;
2029 :
2030 1400240 : if (indexkey < 0)
2031 0 : att_tup = SystemAttributeDefinition(indexkey);
2032 : else
2033 1400240 : att_tup = TupleDescAttr(heapRelation->rd_att, indexkey - 1);
2034 :
2035 1400240 : indexvar = (Expr *) makeVar(varno,
2036 : indexkey,
2037 1400240 : att_tup->atttypid,
2038 1400240 : att_tup->atttypmod,
2039 1400240 : att_tup->attcollation,
2040 : 0);
2041 : }
2042 : else
2043 : {
2044 : /* expression column */
2045 3016 : if (indexpr_item == NULL)
2046 0 : elog(ERROR, "wrong number of index expressions");
2047 3016 : indexvar = (Expr *) lfirst(indexpr_item);
2048 3016 : indexpr_item = lnext(index->indexprs, indexpr_item);
2049 : }
2050 :
2051 1403256 : tlist = lappend(tlist,
2052 1403256 : makeTargetEntry(indexvar,
2053 1403256 : i + 1,
2054 : NULL,
2055 : false));
2056 : }
2057 743378 : if (indexpr_item != NULL)
2058 0 : elog(ERROR, "wrong number of index expressions");
2059 :
2060 743378 : return tlist;
2061 : }
2062 :
2063 : /*
2064 : * restriction_selectivity
2065 : *
2066 : * Returns the selectivity of a specified restriction operator clause.
2067 : * This code executes registered procedures stored in the
2068 : * operator relation, by calling the function manager.
2069 : *
2070 : * See clause_selectivity() for the meaning of the additional parameters.
2071 : */
2072 : Selectivity
2073 737532 : restriction_selectivity(PlannerInfo *root,
2074 : Oid operatorid,
2075 : List *args,
2076 : Oid inputcollid,
2077 : int varRelid)
2078 : {
2079 737532 : RegProcedure oprrest = get_oprrest(operatorid);
2080 : float8 result;
2081 :
2082 : /*
2083 : * if the oprrest procedure is missing for whatever reason, use a
2084 : * selectivity of 0.5
2085 : */
2086 737532 : if (!oprrest)
2087 160 : return (Selectivity) 0.5;
2088 :
2089 737372 : result = DatumGetFloat8(OidFunctionCall4Coll(oprrest,
2090 : inputcollid,
2091 : PointerGetDatum(root),
2092 : ObjectIdGetDatum(operatorid),
2093 : PointerGetDatum(args),
2094 : Int32GetDatum(varRelid)));
2095 :
2096 737342 : if (result < 0.0 || result > 1.0)
2097 0 : elog(ERROR, "invalid restriction selectivity: %f", result);
2098 :
2099 737342 : return (Selectivity) result;
2100 : }
2101 :
2102 : /*
2103 : * join_selectivity
2104 : *
2105 : * Returns the selectivity of a specified join operator clause.
2106 : * This code executes registered procedures stored in the
2107 : * operator relation, by calling the function manager.
2108 : *
2109 : * See clause_selectivity() for the meaning of the additional parameters.
2110 : */
2111 : Selectivity
2112 252112 : join_selectivity(PlannerInfo *root,
2113 : Oid operatorid,
2114 : List *args,
2115 : Oid inputcollid,
2116 : JoinType jointype,
2117 : SpecialJoinInfo *sjinfo)
2118 : {
2119 252112 : RegProcedure oprjoin = get_oprjoin(operatorid);
2120 : float8 result;
2121 :
2122 : /*
2123 : * if the oprjoin procedure is missing for whatever reason, use a
2124 : * selectivity of 0.5
2125 : */
2126 252112 : if (!oprjoin)
2127 146 : return (Selectivity) 0.5;
2128 :
2129 251966 : result = DatumGetFloat8(OidFunctionCall5Coll(oprjoin,
2130 : inputcollid,
2131 : PointerGetDatum(root),
2132 : ObjectIdGetDatum(operatorid),
2133 : PointerGetDatum(args),
2134 : Int16GetDatum(jointype),
2135 : PointerGetDatum(sjinfo)));
2136 :
2137 251966 : if (result < 0.0 || result > 1.0)
2138 0 : elog(ERROR, "invalid join selectivity: %f", result);
2139 :
2140 251966 : return (Selectivity) result;
2141 : }
2142 :
2143 : /*
2144 : * function_selectivity
2145 : *
2146 : * Attempt to estimate the selectivity of a specified boolean function clause
2147 : * by asking its support function. If the function lacks support, return -1.
2148 : *
2149 : * See clause_selectivity() for the meaning of the additional parameters.
2150 : */
2151 : Selectivity
2152 12216 : function_selectivity(PlannerInfo *root,
2153 : Oid funcid,
2154 : List *args,
2155 : Oid inputcollid,
2156 : bool is_join,
2157 : int varRelid,
2158 : JoinType jointype,
2159 : SpecialJoinInfo *sjinfo)
2160 : {
2161 12216 : RegProcedure prosupport = get_func_support(funcid);
2162 : SupportRequestSelectivity req;
2163 : SupportRequestSelectivity *sresult;
2164 :
2165 12216 : if (!prosupport)
2166 12186 : return (Selectivity) -1; /* no support function */
2167 :
2168 30 : req.type = T_SupportRequestSelectivity;
2169 30 : req.root = root;
2170 30 : req.funcid = funcid;
2171 30 : req.args = args;
2172 30 : req.inputcollid = inputcollid;
2173 30 : req.is_join = is_join;
2174 30 : req.varRelid = varRelid;
2175 30 : req.jointype = jointype;
2176 30 : req.sjinfo = sjinfo;
2177 30 : req.selectivity = -1; /* to catch failure to set the value */
2178 :
2179 : sresult = (SupportRequestSelectivity *)
2180 30 : DatumGetPointer(OidFunctionCall1(prosupport,
2181 : PointerGetDatum(&req)));
2182 :
2183 30 : if (sresult != &req)
2184 0 : return (Selectivity) -1; /* function did not honor request */
2185 :
2186 30 : if (req.selectivity < 0.0 || req.selectivity > 1.0)
2187 0 : elog(ERROR, "invalid function selectivity: %f", req.selectivity);
2188 :
2189 30 : return (Selectivity) req.selectivity;
2190 : }
2191 :
2192 : /*
2193 : * add_function_cost
2194 : *
2195 : * Get an estimate of the execution cost of a function, and *add* it to
2196 : * the contents of *cost. The estimate may include both one-time and
2197 : * per-tuple components, since QualCost does.
2198 : *
2199 : * The funcid must always be supplied. If it is being called as the
2200 : * implementation of a specific parsetree node (FuncExpr, OpExpr,
2201 : * WindowFunc, etc), pass that as "node", else pass NULL.
2202 : *
2203 : * In some usages root might be NULL, too.
2204 : */
2205 : void
2206 1142322 : add_function_cost(PlannerInfo *root, Oid funcid, Node *node,
2207 : QualCost *cost)
2208 : {
2209 : HeapTuple proctup;
2210 : Form_pg_proc procform;
2211 :
2212 1142322 : proctup = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
2213 1142322 : if (!HeapTupleIsValid(proctup))
2214 0 : elog(ERROR, "cache lookup failed for function %u", funcid);
2215 1142322 : procform = (Form_pg_proc) GETSTRUCT(proctup);
2216 :
2217 1142322 : if (OidIsValid(procform->prosupport))
2218 : {
2219 : SupportRequestCost req;
2220 : SupportRequestCost *sresult;
2221 :
2222 35178 : req.type = T_SupportRequestCost;
2223 35178 : req.root = root;
2224 35178 : req.funcid = funcid;
2225 35178 : req.node = node;
2226 :
2227 : /* Initialize cost fields so that support function doesn't have to */
2228 35178 : req.startup = 0;
2229 35178 : req.per_tuple = 0;
2230 :
2231 : sresult = (SupportRequestCost *)
2232 35178 : DatumGetPointer(OidFunctionCall1(procform->prosupport,
2233 : PointerGetDatum(&req)));
2234 :
2235 35178 : if (sresult == &req)
2236 : {
2237 : /* Success, so accumulate support function's estimate into *cost */
2238 18 : cost->startup += req.startup;
2239 18 : cost->per_tuple += req.per_tuple;
2240 18 : ReleaseSysCache(proctup);
2241 18 : return;
2242 : }
2243 : }
2244 :
2245 : /* No support function, or it failed, so rely on procost */
2246 1142304 : cost->per_tuple += procform->procost * cpu_operator_cost;
2247 :
2248 1142304 : ReleaseSysCache(proctup);
2249 : }
2250 :
2251 : /*
2252 : * get_function_rows
2253 : *
2254 : * Get an estimate of the number of rows returned by a set-returning function.
2255 : *
2256 : * The funcid must always be supplied. In current usage, the calling node
2257 : * will always be supplied, and will be either a FuncExpr or OpExpr.
2258 : * But it's a good idea to not fail if it's NULL.
2259 : *
2260 : * In some usages root might be NULL, too.
2261 : *
2262 : * Note: this returns the unfiltered result of the support function, if any.
2263 : * It's usually a good idea to apply clamp_row_est() to the result, but we
2264 : * leave it to the caller to do so.
2265 : */
2266 : double
2267 55456 : get_function_rows(PlannerInfo *root, Oid funcid, Node *node)
2268 : {
2269 : HeapTuple proctup;
2270 : Form_pg_proc procform;
2271 : double result;
2272 :
2273 55456 : proctup = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
2274 55456 : if (!HeapTupleIsValid(proctup))
2275 0 : elog(ERROR, "cache lookup failed for function %u", funcid);
2276 55456 : procform = (Form_pg_proc) GETSTRUCT(proctup);
2277 :
2278 : Assert(procform->proretset); /* else caller error */
2279 :
2280 55456 : if (OidIsValid(procform->prosupport))
2281 : {
2282 : SupportRequestRows req;
2283 : SupportRequestRows *sresult;
2284 :
2285 21006 : req.type = T_SupportRequestRows;
2286 21006 : req.root = root;
2287 21006 : req.funcid = funcid;
2288 21006 : req.node = node;
2289 :
2290 21006 : req.rows = 0; /* just for sanity */
2291 :
2292 : sresult = (SupportRequestRows *)
2293 21006 : DatumGetPointer(OidFunctionCall1(procform->prosupport,
2294 : PointerGetDatum(&req)));
2295 :
2296 21006 : if (sresult == &req)
2297 : {
2298 : /* Success */
2299 16962 : ReleaseSysCache(proctup);
2300 16962 : return req.rows;
2301 : }
2302 : }
2303 :
2304 : /* No support function, or it failed, so rely on prorows */
2305 38494 : result = procform->prorows;
2306 :
2307 38494 : ReleaseSysCache(proctup);
2308 :
2309 38494 : return result;
2310 : }
2311 :
2312 : /*
2313 : * has_unique_index
2314 : *
2315 : * Detect whether there is a unique index on the specified attribute
2316 : * of the specified relation, thus allowing us to conclude that all
2317 : * the (non-null) values of the attribute are distinct.
2318 : *
2319 : * This function does not check the index's indimmediate property, which
2320 : * means that uniqueness may transiently fail to hold intra-transaction.
2321 : * That's appropriate when we are making statistical estimates, but beware
2322 : * of using this for any correctness proofs.
2323 : */
2324 : bool
2325 2210596 : has_unique_index(RelOptInfo *rel, AttrNumber attno)
2326 : {
2327 : ListCell *ilist;
2328 :
2329 5531780 : foreach(ilist, rel->indexlist)
2330 : {
2331 4027086 : IndexOptInfo *index = (IndexOptInfo *) lfirst(ilist);
2332 :
2333 : /*
2334 : * Note: ignore partial indexes, since they don't allow us to conclude
2335 : * that all attr values are distinct, *unless* they are marked predOK
2336 : * which means we know the index's predicate is satisfied by the
2337 : * query. We don't take any interest in expressional indexes either.
2338 : * Also, a multicolumn unique index doesn't allow us to conclude that
2339 : * just the specified attr is unique.
2340 : */
2341 4027086 : if (index->unique &&
2342 2808260 : index->nkeycolumns == 1 &&
2343 1517364 : index->indexkeys[0] == attno &&
2344 705938 : (index->indpred == NIL || index->predOK))
2345 705902 : return true;
2346 : }
2347 1504694 : return false;
2348 : }
2349 :
2350 :
2351 : /*
2352 : * has_row_triggers
2353 : *
2354 : * Detect whether the specified relation has any row-level triggers for event.
2355 : */
2356 : bool
2357 516 : has_row_triggers(PlannerInfo *root, Index rti, CmdType event)
2358 : {
2359 516 : RangeTblEntry *rte = planner_rt_fetch(rti, root);
2360 : Relation relation;
2361 : TriggerDesc *trigDesc;
2362 516 : bool result = false;
2363 :
2364 : /* Assume we already have adequate lock */
2365 516 : relation = table_open(rte->relid, NoLock);
2366 :
2367 516 : trigDesc = relation->trigdesc;
2368 516 : switch (event)
2369 : {
2370 164 : case CMD_INSERT:
2371 164 : if (trigDesc &&
2372 26 : (trigDesc->trig_insert_after_row ||
2373 14 : trigDesc->trig_insert_before_row))
2374 26 : result = true;
2375 164 : break;
2376 190 : case CMD_UPDATE:
2377 190 : if (trigDesc &&
2378 48 : (trigDesc->trig_update_after_row ||
2379 28 : trigDesc->trig_update_before_row))
2380 36 : result = true;
2381 190 : break;
2382 162 : case CMD_DELETE:
2383 162 : if (trigDesc &&
2384 30 : (trigDesc->trig_delete_after_row ||
2385 18 : trigDesc->trig_delete_before_row))
2386 16 : result = true;
2387 162 : break;
2388 : /* There is no separate event for MERGE, only INSERT/UPDATE/DELETE */
2389 0 : case CMD_MERGE:
2390 0 : result = false;
2391 0 : break;
2392 0 : default:
2393 0 : elog(ERROR, "unrecognized CmdType: %d", (int) event);
2394 : break;
2395 : }
2396 :
2397 516 : table_close(relation, NoLock);
2398 516 : return result;
2399 : }
2400 :
2401 : /*
2402 : * has_transition_tables
2403 : *
2404 : * Detect whether the specified relation has any transition tables for event.
2405 : */
2406 : bool
2407 390 : has_transition_tables(PlannerInfo *root, Index rti, CmdType event)
2408 : {
2409 390 : RangeTblEntry *rte = planner_rt_fetch(rti, root);
2410 : Relation relation;
2411 : TriggerDesc *trigDesc;
2412 390 : bool result = false;
2413 :
2414 : Assert(rte->rtekind == RTE_RELATION);
2415 :
2416 : /* Currently foreign tables cannot have transition tables */
2417 390 : if (rte->relkind == RELKIND_FOREIGN_TABLE)
2418 290 : return result;
2419 :
2420 : /* Assume we already have adequate lock */
2421 100 : relation = table_open(rte->relid, NoLock);
2422 :
2423 100 : trigDesc = relation->trigdesc;
2424 100 : switch (event)
2425 : {
2426 0 : case CMD_INSERT:
2427 0 : if (trigDesc &&
2428 0 : trigDesc->trig_insert_new_table)
2429 0 : result = true;
2430 0 : break;
2431 60 : case CMD_UPDATE:
2432 60 : if (trigDesc &&
2433 8 : (trigDesc->trig_update_old_table ||
2434 0 : trigDesc->trig_update_new_table))
2435 8 : result = true;
2436 60 : break;
2437 40 : case CMD_DELETE:
2438 40 : if (trigDesc &&
2439 8 : trigDesc->trig_delete_old_table)
2440 8 : result = true;
2441 40 : break;
2442 : /* There is no separate event for MERGE, only INSERT/UPDATE/DELETE */
2443 0 : case CMD_MERGE:
2444 0 : result = false;
2445 0 : break;
2446 0 : default:
2447 0 : elog(ERROR, "unrecognized CmdType: %d", (int) event);
2448 : break;
2449 : }
2450 :
2451 100 : table_close(relation, NoLock);
2452 100 : return result;
2453 : }
2454 :
2455 : /*
2456 : * has_stored_generated_columns
2457 : *
2458 : * Does table identified by RTI have any STORED GENERATED columns?
2459 : */
2460 : bool
2461 438 : has_stored_generated_columns(PlannerInfo *root, Index rti)
2462 : {
2463 438 : RangeTblEntry *rte = planner_rt_fetch(rti, root);
2464 : Relation relation;
2465 : TupleDesc tupdesc;
2466 438 : bool result = false;
2467 :
2468 : /* Assume we already have adequate lock */
2469 438 : relation = table_open(rte->relid, NoLock);
2470 :
2471 438 : tupdesc = RelationGetDescr(relation);
2472 438 : result = tupdesc->constr && tupdesc->constr->has_generated_stored;
2473 :
2474 438 : table_close(relation, NoLock);
2475 :
2476 438 : return result;
2477 : }
2478 :
2479 : /*
2480 : * get_dependent_generated_columns
2481 : *
2482 : * Get the column numbers of any STORED GENERATED columns of the relation
2483 : * that depend on any column listed in target_cols. Both the input and
2484 : * result bitmapsets contain column numbers offset by
2485 : * FirstLowInvalidHeapAttributeNumber.
2486 : */
2487 : Bitmapset *
2488 90 : get_dependent_generated_columns(PlannerInfo *root, Index rti,
2489 : Bitmapset *target_cols)
2490 : {
2491 90 : Bitmapset *dependentCols = NULL;
2492 90 : RangeTblEntry *rte = planner_rt_fetch(rti, root);
2493 : Relation relation;
2494 : TupleDesc tupdesc;
2495 : TupleConstr *constr;
2496 :
2497 : /* Assume we already have adequate lock */
2498 90 : relation = table_open(rte->relid, NoLock);
2499 :
2500 90 : tupdesc = RelationGetDescr(relation);
2501 90 : constr = tupdesc->constr;
2502 :
2503 90 : if (constr && constr->has_generated_stored)
2504 : {
2505 12 : for (int i = 0; i < constr->num_defval; i++)
2506 : {
2507 8 : AttrDefault *defval = &constr->defval[i];
2508 : Node *expr;
2509 8 : Bitmapset *attrs_used = NULL;
2510 :
2511 : /* skip if not generated column */
2512 8 : if (!TupleDescAttr(tupdesc, defval->adnum - 1)->attgenerated)
2513 0 : continue;
2514 :
2515 : /* identify columns this generated column depends on */
2516 8 : expr = stringToNode(defval->adbin);
2517 8 : pull_varattnos(expr, 1, &attrs_used);
2518 :
2519 8 : if (bms_overlap(target_cols, attrs_used))
2520 8 : dependentCols = bms_add_member(dependentCols,
2521 8 : defval->adnum - FirstLowInvalidHeapAttributeNumber);
2522 : }
2523 : }
2524 :
2525 90 : table_close(relation, NoLock);
2526 :
2527 90 : return dependentCols;
2528 : }
2529 :
2530 : /*
2531 : * set_relation_partition_info
2532 : *
2533 : * Set partitioning scheme and related information for a partitioned table.
2534 : */
2535 : static void
2536 16982 : set_relation_partition_info(PlannerInfo *root, RelOptInfo *rel,
2537 : Relation relation)
2538 : {
2539 : PartitionDesc partdesc;
2540 :
2541 : /*
2542 : * Create the PartitionDirectory infrastructure if we didn't already.
2543 : */
2544 16982 : if (root->glob->partition_directory == NULL)
2545 : {
2546 11596 : root->glob->partition_directory =
2547 11596 : CreatePartitionDirectory(CurrentMemoryContext, true);
2548 : }
2549 :
2550 16982 : partdesc = PartitionDirectoryLookup(root->glob->partition_directory,
2551 : relation);
2552 16982 : rel->part_scheme = find_partition_scheme(root, relation);
2553 : Assert(partdesc != NULL && rel->part_scheme != NULL);
2554 16982 : rel->boundinfo = partdesc->boundinfo;
2555 16982 : rel->nparts = partdesc->nparts;
2556 16982 : set_baserel_partition_key_exprs(relation, rel);
2557 16982 : set_baserel_partition_constraint(relation, rel);
2558 16982 : }
2559 :
2560 : /*
2561 : * find_partition_scheme
2562 : *
2563 : * Find or create a PartitionScheme for this Relation.
2564 : */
2565 : static PartitionScheme
2566 16982 : find_partition_scheme(PlannerInfo *root, Relation relation)
2567 : {
2568 16982 : PartitionKey partkey = RelationGetPartitionKey(relation);
2569 : ListCell *lc;
2570 : int partnatts,
2571 : i;
2572 : PartitionScheme part_scheme;
2573 :
2574 : /* A partitioned table should have a partition key. */
2575 : Assert(partkey != NULL);
2576 :
2577 16982 : partnatts = partkey->partnatts;
2578 :
2579 : /* Search for a matching partition scheme and return if found one. */
2580 18872 : foreach(lc, root->part_schemes)
2581 : {
2582 5978 : part_scheme = lfirst(lc);
2583 :
2584 : /* Match partitioning strategy and number of keys. */
2585 5978 : if (partkey->strategy != part_scheme->strategy ||
2586 4988 : partnatts != part_scheme->partnatts)
2587 1440 : continue;
2588 :
2589 : /* Match partition key type properties. */
2590 4538 : if (memcmp(partkey->partopfamily, part_scheme->partopfamily,
2591 4088 : sizeof(Oid) * partnatts) != 0 ||
2592 4088 : memcmp(partkey->partopcintype, part_scheme->partopcintype,
2593 4088 : sizeof(Oid) * partnatts) != 0 ||
2594 4088 : memcmp(partkey->partcollation, part_scheme->partcollation,
2595 : sizeof(Oid) * partnatts) != 0)
2596 450 : continue;
2597 :
2598 : /*
2599 : * Length and byval information should match when partopcintype
2600 : * matches.
2601 : */
2602 : Assert(memcmp(partkey->parttyplen, part_scheme->parttyplen,
2603 : sizeof(int16) * partnatts) == 0);
2604 : Assert(memcmp(partkey->parttypbyval, part_scheme->parttypbyval,
2605 : sizeof(bool) * partnatts) == 0);
2606 :
2607 : /*
2608 : * If partopfamily and partopcintype matched, must have the same
2609 : * partition comparison functions. Note that we cannot reliably
2610 : * Assert the equality of function structs themselves for they might
2611 : * be different across PartitionKey's, so just Assert for the function
2612 : * OIDs.
2613 : */
2614 : #ifdef USE_ASSERT_CHECKING
2615 : for (i = 0; i < partkey->partnatts; i++)
2616 : Assert(partkey->partsupfunc[i].fn_oid ==
2617 : part_scheme->partsupfunc[i].fn_oid);
2618 : #endif
2619 :
2620 : /* Found matching partition scheme. */
2621 4088 : return part_scheme;
2622 : }
2623 :
2624 : /*
2625 : * Did not find matching partition scheme. Create one copying relevant
2626 : * information from the relcache. We need to copy the contents of the
2627 : * array since the relcache entry may not survive after we have closed the
2628 : * relation.
2629 : */
2630 12894 : part_scheme = (PartitionScheme) palloc0(sizeof(PartitionSchemeData));
2631 12894 : part_scheme->strategy = partkey->strategy;
2632 12894 : part_scheme->partnatts = partkey->partnatts;
2633 :
2634 12894 : part_scheme->partopfamily = (Oid *) palloc(sizeof(Oid) * partnatts);
2635 12894 : memcpy(part_scheme->partopfamily, partkey->partopfamily,
2636 : sizeof(Oid) * partnatts);
2637 :
2638 12894 : part_scheme->partopcintype = (Oid *) palloc(sizeof(Oid) * partnatts);
2639 12894 : memcpy(part_scheme->partopcintype, partkey->partopcintype,
2640 : sizeof(Oid) * partnatts);
2641 :
2642 12894 : part_scheme->partcollation = (Oid *) palloc(sizeof(Oid) * partnatts);
2643 12894 : memcpy(part_scheme->partcollation, partkey->partcollation,
2644 : sizeof(Oid) * partnatts);
2645 :
2646 12894 : part_scheme->parttyplen = (int16 *) palloc(sizeof(int16) * partnatts);
2647 12894 : memcpy(part_scheme->parttyplen, partkey->parttyplen,
2648 : sizeof(int16) * partnatts);
2649 :
2650 12894 : part_scheme->parttypbyval = (bool *) palloc(sizeof(bool) * partnatts);
2651 12894 : memcpy(part_scheme->parttypbyval, partkey->parttypbyval,
2652 : sizeof(bool) * partnatts);
2653 :
2654 12894 : part_scheme->partsupfunc = (FmgrInfo *)
2655 12894 : palloc(sizeof(FmgrInfo) * partnatts);
2656 27636 : for (i = 0; i < partnatts; i++)
2657 14742 : fmgr_info_copy(&part_scheme->partsupfunc[i], &partkey->partsupfunc[i],
2658 : CurrentMemoryContext);
2659 :
2660 : /* Add the partitioning scheme to PlannerInfo. */
2661 12894 : root->part_schemes = lappend(root->part_schemes, part_scheme);
2662 :
2663 12894 : return part_scheme;
2664 : }
2665 :
2666 : /*
2667 : * set_baserel_partition_key_exprs
2668 : *
2669 : * Builds partition key expressions for the given base relation and fills
2670 : * rel->partexprs.
2671 : */
2672 : static void
2673 16982 : set_baserel_partition_key_exprs(Relation relation,
2674 : RelOptInfo *rel)
2675 : {
2676 16982 : PartitionKey partkey = RelationGetPartitionKey(relation);
2677 : int partnatts;
2678 : int cnt;
2679 : List **partexprs;
2680 : ListCell *lc;
2681 16982 : Index varno = rel->relid;
2682 :
2683 : Assert(IS_SIMPLE_REL(rel) && rel->relid > 0);
2684 :
2685 : /* A partitioned table should have a partition key. */
2686 : Assert(partkey != NULL);
2687 :
2688 16982 : partnatts = partkey->partnatts;
2689 16982 : partexprs = (List **) palloc(sizeof(List *) * partnatts);
2690 16982 : lc = list_head(partkey->partexprs);
2691 :
2692 35842 : for (cnt = 0; cnt < partnatts; cnt++)
2693 : {
2694 : Expr *partexpr;
2695 18860 : AttrNumber attno = partkey->partattrs[cnt];
2696 :
2697 18860 : if (attno != InvalidAttrNumber)
2698 : {
2699 : /* Single column partition key is stored as a Var node. */
2700 : Assert(attno > 0);
2701 :
2702 17930 : partexpr = (Expr *) makeVar(varno, attno,
2703 17930 : partkey->parttypid[cnt],
2704 17930 : partkey->parttypmod[cnt],
2705 17930 : partkey->parttypcoll[cnt], 0);
2706 : }
2707 : else
2708 : {
2709 930 : if (lc == NULL)
2710 0 : elog(ERROR, "wrong number of partition key expressions");
2711 :
2712 : /* Re-stamp the expression with given varno. */
2713 930 : partexpr = (Expr *) copyObject(lfirst(lc));
2714 930 : ChangeVarNodes((Node *) partexpr, 1, varno, 0);
2715 930 : lc = lnext(partkey->partexprs, lc);
2716 : }
2717 :
2718 : /* Base relations have a single expression per key. */
2719 18860 : partexprs[cnt] = list_make1(partexpr);
2720 : }
2721 :
2722 16982 : rel->partexprs = partexprs;
2723 :
2724 : /*
2725 : * A base relation does not have nullable partition key expressions, since
2726 : * no outer join is involved. We still allocate an array of empty
2727 : * expression lists to keep partition key expression handling code simple.
2728 : * See build_joinrel_partition_info() and match_expr_to_partition_keys().
2729 : */
2730 16982 : rel->nullable_partexprs = (List **) palloc0(sizeof(List *) * partnatts);
2731 16982 : }
2732 :
2733 : /*
2734 : * set_baserel_partition_constraint
2735 : *
2736 : * Builds the partition constraint for the given base relation and sets it
2737 : * in the given RelOptInfo. All Var nodes are restamped with the relid of the
2738 : * given relation.
2739 : */
2740 : static void
2741 16994 : set_baserel_partition_constraint(Relation relation, RelOptInfo *rel)
2742 : {
2743 : List *partconstr;
2744 :
2745 16994 : if (rel->partition_qual) /* already done */
2746 0 : return;
2747 :
2748 : /*
2749 : * Run the partition quals through const-simplification similar to check
2750 : * constraints. We skip canonicalize_qual, though, because partition
2751 : * quals should be in canonical form already; also, since the qual is in
2752 : * implicit-AND format, we'd have to explicitly convert it to explicit-AND
2753 : * format and back again.
2754 : */
2755 16994 : partconstr = RelationGetPartitionQual(relation);
2756 16994 : if (partconstr)
2757 : {
2758 3430 : partconstr = (List *) expression_planner((Expr *) partconstr);
2759 3430 : if (rel->relid != 1)
2760 3348 : ChangeVarNodes((Node *) partconstr, 1, rel->relid, 0);
2761 3430 : rel->partition_qual = partconstr;
2762 : }
2763 : }
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