Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * pg_constraint.c
4 : * routines to support manipulation of the pg_constraint relation
5 : *
6 : * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
7 : * Portions Copyright (c) 1994, Regents of the University of California
8 : *
9 : *
10 : * IDENTIFICATION
11 : * src/backend/catalog/pg_constraint.c
12 : *
13 : *-------------------------------------------------------------------------
14 : */
15 : #include "postgres.h"
16 :
17 : #include "access/genam.h"
18 : #include "access/gist.h"
19 : #include "access/htup_details.h"
20 : #include "access/sysattr.h"
21 : #include "access/table.h"
22 : #include "catalog/catalog.h"
23 : #include "catalog/dependency.h"
24 : #include "catalog/heap.h"
25 : #include "catalog/indexing.h"
26 : #include "catalog/objectaccess.h"
27 : #include "catalog/pg_constraint.h"
28 : #include "catalog/pg_operator.h"
29 : #include "catalog/pg_type.h"
30 : #include "commands/defrem.h"
31 : #include "common/int.h"
32 : #include "utils/array.h"
33 : #include "utils/builtins.h"
34 : #include "utils/fmgroids.h"
35 : #include "utils/lsyscache.h"
36 : #include "utils/rel.h"
37 : #include "utils/syscache.h"
38 :
39 :
40 : /*
41 : * CreateConstraintEntry
42 : * Create a constraint table entry.
43 : *
44 : * Subsidiary records (such as triggers or indexes to implement the
45 : * constraint) are *not* created here. But we do make dependency links
46 : * from the constraint to the things it depends on.
47 : *
48 : * The new constraint's OID is returned.
49 : */
50 : Oid
51 53616 : CreateConstraintEntry(const char *constraintName,
52 : Oid constraintNamespace,
53 : char constraintType,
54 : bool isDeferrable,
55 : bool isDeferred,
56 : bool isEnforced,
57 : bool isValidated,
58 : Oid parentConstrId,
59 : Oid relId,
60 : const int16 *constraintKey,
61 : int constraintNKeys,
62 : int constraintNTotalKeys,
63 : Oid domainId,
64 : Oid indexRelId,
65 : Oid foreignRelId,
66 : const int16 *foreignKey,
67 : const Oid *pfEqOp,
68 : const Oid *ppEqOp,
69 : const Oid *ffEqOp,
70 : int foreignNKeys,
71 : char foreignUpdateType,
72 : char foreignDeleteType,
73 : const int16 *fkDeleteSetCols,
74 : int numFkDeleteSetCols,
75 : char foreignMatchType,
76 : const Oid *exclOp,
77 : Node *conExpr,
78 : const char *conBin,
79 : bool conIsLocal,
80 : int16 conInhCount,
81 : bool conNoInherit,
82 : bool conPeriod,
83 : bool is_internal)
84 : {
85 : Relation conDesc;
86 : Oid conOid;
87 : HeapTuple tup;
88 : bool nulls[Natts_pg_constraint];
89 : Datum values[Natts_pg_constraint];
90 : ArrayType *conkeyArray;
91 : ArrayType *confkeyArray;
92 : ArrayType *conpfeqopArray;
93 : ArrayType *conppeqopArray;
94 : ArrayType *conffeqopArray;
95 : ArrayType *conexclopArray;
96 : ArrayType *confdelsetcolsArray;
97 : NameData cname;
98 : int i;
99 : ObjectAddress conobject;
100 : ObjectAddresses *addrs_auto;
101 : ObjectAddresses *addrs_normal;
102 :
103 : /* Only CHECK or FOREIGN KEY constraint can be not enforced */
104 : Assert(isEnforced || constraintType == CONSTRAINT_CHECK ||
105 : constraintType == CONSTRAINT_FOREIGN);
106 : /* NOT ENFORCED constraint must be NOT VALID */
107 : Assert(isEnforced || !isValidated);
108 :
109 53616 : conDesc = table_open(ConstraintRelationId, RowExclusiveLock);
110 :
111 : Assert(constraintName);
112 53616 : namestrcpy(&cname, constraintName);
113 :
114 : /*
115 : * Convert C arrays into Postgres arrays.
116 : */
117 53616 : if (constraintNKeys > 0)
118 : {
119 : Datum *conkey;
120 :
121 52618 : conkey = (Datum *) palloc(constraintNKeys * sizeof(Datum));
122 115406 : for (i = 0; i < constraintNKeys; i++)
123 62788 : conkey[i] = Int16GetDatum(constraintKey[i]);
124 52618 : conkeyArray = construct_array_builtin(conkey, constraintNKeys, INT2OID);
125 : }
126 : else
127 998 : conkeyArray = NULL;
128 :
129 53616 : if (foreignNKeys > 0)
130 : {
131 : Datum *fkdatums;
132 4100 : int nkeys = Max(foreignNKeys, numFkDeleteSetCols);
133 :
134 4100 : fkdatums = (Datum *) palloc(nkeys * sizeof(Datum));
135 9430 : for (i = 0; i < foreignNKeys; i++)
136 5330 : fkdatums[i] = Int16GetDatum(foreignKey[i]);
137 4100 : confkeyArray = construct_array_builtin(fkdatums, foreignNKeys, INT2OID);
138 9430 : for (i = 0; i < foreignNKeys; i++)
139 5330 : fkdatums[i] = ObjectIdGetDatum(pfEqOp[i]);
140 4100 : conpfeqopArray = construct_array_builtin(fkdatums, foreignNKeys, OIDOID);
141 9430 : for (i = 0; i < foreignNKeys; i++)
142 5330 : fkdatums[i] = ObjectIdGetDatum(ppEqOp[i]);
143 4100 : conppeqopArray = construct_array_builtin(fkdatums, foreignNKeys, OIDOID);
144 9430 : for (i = 0; i < foreignNKeys; i++)
145 5330 : fkdatums[i] = ObjectIdGetDatum(ffEqOp[i]);
146 4100 : conffeqopArray = construct_array_builtin(fkdatums, foreignNKeys, OIDOID);
147 :
148 4100 : if (numFkDeleteSetCols > 0)
149 : {
150 120 : for (i = 0; i < numFkDeleteSetCols; i++)
151 60 : fkdatums[i] = Int16GetDatum(fkDeleteSetCols[i]);
152 60 : confdelsetcolsArray = construct_array_builtin(fkdatums, numFkDeleteSetCols, INT2OID);
153 : }
154 : else
155 4040 : confdelsetcolsArray = NULL;
156 : }
157 : else
158 : {
159 49516 : confkeyArray = NULL;
160 49516 : conpfeqopArray = NULL;
161 49516 : conppeqopArray = NULL;
162 49516 : conffeqopArray = NULL;
163 49516 : confdelsetcolsArray = NULL;
164 : }
165 :
166 53616 : if (exclOp != NULL)
167 : {
168 : Datum *opdatums;
169 :
170 832 : opdatums = (Datum *) palloc(constraintNKeys * sizeof(Datum));
171 2426 : for (i = 0; i < constraintNKeys; i++)
172 1594 : opdatums[i] = ObjectIdGetDatum(exclOp[i]);
173 832 : conexclopArray = construct_array_builtin(opdatums, constraintNKeys, OIDOID);
174 : }
175 : else
176 52784 : conexclopArray = NULL;
177 :
178 : /* initialize nulls and values */
179 1554864 : for (i = 0; i < Natts_pg_constraint; i++)
180 : {
181 1501248 : nulls[i] = false;
182 1501248 : values[i] = (Datum) 0;
183 : }
184 :
185 53616 : conOid = GetNewOidWithIndex(conDesc, ConstraintOidIndexId,
186 : Anum_pg_constraint_oid);
187 53616 : values[Anum_pg_constraint_oid - 1] = ObjectIdGetDatum(conOid);
188 53616 : values[Anum_pg_constraint_conname - 1] = NameGetDatum(&cname);
189 53616 : values[Anum_pg_constraint_connamespace - 1] = ObjectIdGetDatum(constraintNamespace);
190 53616 : values[Anum_pg_constraint_contype - 1] = CharGetDatum(constraintType);
191 53616 : values[Anum_pg_constraint_condeferrable - 1] = BoolGetDatum(isDeferrable);
192 53616 : values[Anum_pg_constraint_condeferred - 1] = BoolGetDatum(isDeferred);
193 53616 : values[Anum_pg_constraint_conenforced - 1] = BoolGetDatum(isEnforced);
194 53616 : values[Anum_pg_constraint_convalidated - 1] = BoolGetDatum(isValidated);
195 53616 : values[Anum_pg_constraint_conrelid - 1] = ObjectIdGetDatum(relId);
196 53616 : values[Anum_pg_constraint_contypid - 1] = ObjectIdGetDatum(domainId);
197 53616 : values[Anum_pg_constraint_conindid - 1] = ObjectIdGetDatum(indexRelId);
198 53616 : values[Anum_pg_constraint_conparentid - 1] = ObjectIdGetDatum(parentConstrId);
199 53616 : values[Anum_pg_constraint_confrelid - 1] = ObjectIdGetDatum(foreignRelId);
200 53616 : values[Anum_pg_constraint_confupdtype - 1] = CharGetDatum(foreignUpdateType);
201 53616 : values[Anum_pg_constraint_confdeltype - 1] = CharGetDatum(foreignDeleteType);
202 53616 : values[Anum_pg_constraint_confmatchtype - 1] = CharGetDatum(foreignMatchType);
203 53616 : values[Anum_pg_constraint_conislocal - 1] = BoolGetDatum(conIsLocal);
204 53616 : values[Anum_pg_constraint_coninhcount - 1] = Int16GetDatum(conInhCount);
205 53616 : values[Anum_pg_constraint_connoinherit - 1] = BoolGetDatum(conNoInherit);
206 53616 : values[Anum_pg_constraint_conperiod - 1] = BoolGetDatum(conPeriod);
207 :
208 53616 : if (conkeyArray)
209 52618 : values[Anum_pg_constraint_conkey - 1] = PointerGetDatum(conkeyArray);
210 : else
211 998 : nulls[Anum_pg_constraint_conkey - 1] = true;
212 :
213 53616 : if (confkeyArray)
214 4100 : values[Anum_pg_constraint_confkey - 1] = PointerGetDatum(confkeyArray);
215 : else
216 49516 : nulls[Anum_pg_constraint_confkey - 1] = true;
217 :
218 53616 : if (conpfeqopArray)
219 4100 : values[Anum_pg_constraint_conpfeqop - 1] = PointerGetDatum(conpfeqopArray);
220 : else
221 49516 : nulls[Anum_pg_constraint_conpfeqop - 1] = true;
222 :
223 53616 : if (conppeqopArray)
224 4100 : values[Anum_pg_constraint_conppeqop - 1] = PointerGetDatum(conppeqopArray);
225 : else
226 49516 : nulls[Anum_pg_constraint_conppeqop - 1] = true;
227 :
228 53616 : if (conffeqopArray)
229 4100 : values[Anum_pg_constraint_conffeqop - 1] = PointerGetDatum(conffeqopArray);
230 : else
231 49516 : nulls[Anum_pg_constraint_conffeqop - 1] = true;
232 :
233 53616 : if (confdelsetcolsArray)
234 60 : values[Anum_pg_constraint_confdelsetcols - 1] = PointerGetDatum(confdelsetcolsArray);
235 : else
236 53556 : nulls[Anum_pg_constraint_confdelsetcols - 1] = true;
237 :
238 53616 : if (conexclopArray)
239 832 : values[Anum_pg_constraint_conexclop - 1] = PointerGetDatum(conexclopArray);
240 : else
241 52784 : nulls[Anum_pg_constraint_conexclop - 1] = true;
242 :
243 53616 : if (conBin)
244 3318 : values[Anum_pg_constraint_conbin - 1] = CStringGetTextDatum(conBin);
245 : else
246 50298 : nulls[Anum_pg_constraint_conbin - 1] = true;
247 :
248 53616 : tup = heap_form_tuple(RelationGetDescr(conDesc), values, nulls);
249 :
250 53616 : CatalogTupleInsert(conDesc, tup);
251 :
252 53616 : ObjectAddressSet(conobject, ConstraintRelationId, conOid);
253 :
254 53616 : table_close(conDesc, RowExclusiveLock);
255 :
256 : /* Handle set of auto dependencies */
257 53616 : addrs_auto = new_object_addresses();
258 :
259 53616 : if (OidIsValid(relId))
260 : {
261 : /*
262 : * Register auto dependency from constraint to owning relation, or to
263 : * specific column(s) if any are mentioned.
264 : */
265 : ObjectAddress relobject;
266 :
267 52790 : if (constraintNTotalKeys > 0)
268 : {
269 115714 : for (i = 0; i < constraintNTotalKeys; i++)
270 : {
271 63096 : ObjectAddressSubSet(relobject, RelationRelationId, relId,
272 : constraintKey[i]);
273 63096 : add_exact_object_address(&relobject, addrs_auto);
274 : }
275 : }
276 : else
277 : {
278 172 : ObjectAddressSet(relobject, RelationRelationId, relId);
279 172 : add_exact_object_address(&relobject, addrs_auto);
280 : }
281 : }
282 :
283 53616 : if (OidIsValid(domainId))
284 : {
285 : /*
286 : * Register auto dependency from constraint to owning domain
287 : */
288 : ObjectAddress domobject;
289 :
290 826 : ObjectAddressSet(domobject, TypeRelationId, domainId);
291 826 : add_exact_object_address(&domobject, addrs_auto);
292 : }
293 :
294 53616 : record_object_address_dependencies(&conobject, addrs_auto,
295 : DEPENDENCY_AUTO);
296 53616 : free_object_addresses(addrs_auto);
297 :
298 : /* Handle set of normal dependencies */
299 53616 : addrs_normal = new_object_addresses();
300 :
301 53616 : if (OidIsValid(foreignRelId))
302 : {
303 : /*
304 : * Register normal dependency from constraint to foreign relation, or
305 : * to specific column(s) if any are mentioned.
306 : */
307 : ObjectAddress relobject;
308 :
309 4100 : if (foreignNKeys > 0)
310 : {
311 9430 : for (i = 0; i < foreignNKeys; i++)
312 : {
313 5330 : ObjectAddressSubSet(relobject, RelationRelationId,
314 : foreignRelId, foreignKey[i]);
315 5330 : add_exact_object_address(&relobject, addrs_normal);
316 : }
317 : }
318 : else
319 : {
320 0 : ObjectAddressSet(relobject, RelationRelationId, foreignRelId);
321 0 : add_exact_object_address(&relobject, addrs_normal);
322 : }
323 : }
324 :
325 53616 : if (OidIsValid(indexRelId) && constraintType == CONSTRAINT_FOREIGN)
326 : {
327 : /*
328 : * Register normal dependency on the unique index that supports a
329 : * foreign-key constraint. (Note: for indexes associated with unique
330 : * or primary-key constraints, the dependency runs the other way, and
331 : * is not made here.)
332 : */
333 : ObjectAddress relobject;
334 :
335 4100 : ObjectAddressSet(relobject, RelationRelationId, indexRelId);
336 4100 : add_exact_object_address(&relobject, addrs_normal);
337 : }
338 :
339 53616 : if (foreignNKeys > 0)
340 : {
341 : /*
342 : * Register normal dependencies on the equality operators that support
343 : * a foreign-key constraint. If the PK and FK types are the same then
344 : * all three operators for a column are the same; otherwise they are
345 : * different.
346 : */
347 : ObjectAddress oprobject;
348 :
349 4100 : oprobject.classId = OperatorRelationId;
350 4100 : oprobject.objectSubId = 0;
351 :
352 9430 : for (i = 0; i < foreignNKeys; i++)
353 : {
354 5330 : oprobject.objectId = pfEqOp[i];
355 5330 : add_exact_object_address(&oprobject, addrs_normal);
356 5330 : if (ppEqOp[i] != pfEqOp[i])
357 : {
358 56 : oprobject.objectId = ppEqOp[i];
359 56 : add_exact_object_address(&oprobject, addrs_normal);
360 : }
361 5330 : if (ffEqOp[i] != pfEqOp[i])
362 : {
363 56 : oprobject.objectId = ffEqOp[i];
364 56 : add_exact_object_address(&oprobject, addrs_normal);
365 : }
366 : }
367 : }
368 :
369 53616 : record_object_address_dependencies(&conobject, addrs_normal,
370 : DEPENDENCY_NORMAL);
371 53616 : free_object_addresses(addrs_normal);
372 :
373 : /*
374 : * We don't bother to register dependencies on the exclusion operators of
375 : * an exclusion constraint. We assume they are members of the opclass
376 : * supporting the index, so there's an indirect dependency via that. (This
377 : * would be pretty dicey for cross-type operators, but exclusion operators
378 : * can never be cross-type.)
379 : */
380 :
381 53616 : if (conExpr != NULL)
382 : {
383 : /*
384 : * Register dependencies from constraint to objects mentioned in CHECK
385 : * expression.
386 : */
387 3318 : recordDependencyOnSingleRelExpr(&conobject, conExpr, relId,
388 : DEPENDENCY_NORMAL,
389 : DEPENDENCY_NORMAL, false);
390 : }
391 :
392 : /* Post creation hook for new constraint */
393 53616 : InvokeObjectPostCreateHookArg(ConstraintRelationId, conOid, 0,
394 : is_internal);
395 :
396 53616 : return conOid;
397 : }
398 :
399 : /*
400 : * Test whether given name is currently used as a constraint name
401 : * for the given object (relation or domain).
402 : *
403 : * This is used to decide whether to accept a user-specified constraint name.
404 : * It is deliberately not the same test as ChooseConstraintName uses to decide
405 : * whether an auto-generated name is OK: here, we will allow it unless there
406 : * is an identical constraint name in use *on the same object*.
407 : *
408 : * NB: Caller should hold exclusive lock on the given object, else
409 : * this test can be fooled by concurrent additions.
410 : */
411 : bool
412 17004 : ConstraintNameIsUsed(ConstraintCategory conCat, Oid objId,
413 : const char *conname)
414 : {
415 : bool found;
416 : Relation conDesc;
417 : SysScanDesc conscan;
418 : ScanKeyData skey[3];
419 :
420 17004 : conDesc = table_open(ConstraintRelationId, AccessShareLock);
421 :
422 17004 : ScanKeyInit(&skey[0],
423 : Anum_pg_constraint_conrelid,
424 : BTEqualStrategyNumber, F_OIDEQ,
425 : ObjectIdGetDatum((conCat == CONSTRAINT_RELATION)
426 : ? objId : InvalidOid));
427 17004 : ScanKeyInit(&skey[1],
428 : Anum_pg_constraint_contypid,
429 : BTEqualStrategyNumber, F_OIDEQ,
430 : ObjectIdGetDatum((conCat == CONSTRAINT_DOMAIN)
431 : ? objId : InvalidOid));
432 17004 : ScanKeyInit(&skey[2],
433 : Anum_pg_constraint_conname,
434 : BTEqualStrategyNumber, F_NAMEEQ,
435 : CStringGetDatum(conname));
436 :
437 17004 : conscan = systable_beginscan(conDesc, ConstraintRelidTypidNameIndexId,
438 : true, NULL, 3, skey);
439 :
440 : /* There can be at most one matching row */
441 17004 : found = (HeapTupleIsValid(systable_getnext(conscan)));
442 :
443 17004 : systable_endscan(conscan);
444 17004 : table_close(conDesc, AccessShareLock);
445 :
446 17004 : return found;
447 : }
448 :
449 : /*
450 : * Does any constraint of the given name exist in the given namespace?
451 : *
452 : * This is used for code that wants to match ChooseConstraintName's rule
453 : * that we should avoid autogenerating duplicate constraint names within a
454 : * namespace.
455 : */
456 : bool
457 8882 : ConstraintNameExists(const char *conname, Oid namespaceid)
458 : {
459 : bool found;
460 : Relation conDesc;
461 : SysScanDesc conscan;
462 : ScanKeyData skey[2];
463 :
464 8882 : conDesc = table_open(ConstraintRelationId, AccessShareLock);
465 :
466 8882 : ScanKeyInit(&skey[0],
467 : Anum_pg_constraint_conname,
468 : BTEqualStrategyNumber, F_NAMEEQ,
469 : CStringGetDatum(conname));
470 :
471 8882 : ScanKeyInit(&skey[1],
472 : Anum_pg_constraint_connamespace,
473 : BTEqualStrategyNumber, F_OIDEQ,
474 : ObjectIdGetDatum(namespaceid));
475 :
476 8882 : conscan = systable_beginscan(conDesc, ConstraintNameNspIndexId, true,
477 : NULL, 2, skey);
478 :
479 8882 : found = (HeapTupleIsValid(systable_getnext(conscan)));
480 :
481 8882 : systable_endscan(conscan);
482 8882 : table_close(conDesc, AccessShareLock);
483 :
484 8882 : return found;
485 : }
486 :
487 : /*
488 : * Select a nonconflicting name for a new constraint.
489 : *
490 : * The objective here is to choose a name that is unique within the
491 : * specified namespace. Postgres does not require this, but the SQL
492 : * spec does, and some apps depend on it. Therefore we avoid choosing
493 : * default names that so conflict.
494 : *
495 : * name1, name2, and label are used the same way as for makeObjectName(),
496 : * except that the label can't be NULL; digits will be appended to the label
497 : * if needed to create a name that is unique within the specified namespace.
498 : * If the given label is empty, we only consider names that include at least
499 : * one added digit.
500 : *
501 : * 'others' can be a list of string names already chosen within the current
502 : * command (but not yet reflected into the catalogs); we will not choose
503 : * a duplicate of one of these either.
504 : *
505 : * Note: it is theoretically possible to get a collision anyway, if someone
506 : * else chooses the same name concurrently. This is fairly unlikely to be
507 : * a problem in practice, especially if one is holding an exclusive lock on
508 : * the relation identified by name1.
509 : *
510 : * Returns a palloc'd string.
511 : */
512 : char *
513 25344 : ChooseConstraintName(const char *name1, const char *name2,
514 : const char *label, Oid namespaceid,
515 : List *others)
516 : {
517 25344 : int pass = 0;
518 25344 : char *conname = NULL;
519 : char modlabel[NAMEDATALEN];
520 : Relation conDesc;
521 : SysScanDesc conscan;
522 : ScanKeyData skey[2];
523 : bool found;
524 : ListCell *l;
525 :
526 25344 : conDesc = table_open(ConstraintRelationId, AccessShareLock);
527 :
528 : /* try the unmodified label first, unless it's empty */
529 25344 : if (label[0] != '\0')
530 24168 : strlcpy(modlabel, label, sizeof(modlabel));
531 : else
532 1176 : snprintf(modlabel, sizeof(modlabel), "%s%d", label, ++pass);
533 :
534 : for (;;)
535 : {
536 28544 : conname = makeObjectName(name1, name2, modlabel);
537 :
538 28544 : found = false;
539 :
540 32688 : foreach(l, others)
541 : {
542 4162 : if (strcmp((char *) lfirst(l), conname) == 0)
543 : {
544 18 : found = true;
545 18 : break;
546 : }
547 : }
548 :
549 28544 : if (!found)
550 : {
551 28526 : ScanKeyInit(&skey[0],
552 : Anum_pg_constraint_conname,
553 : BTEqualStrategyNumber, F_NAMEEQ,
554 : CStringGetDatum(conname));
555 :
556 28526 : ScanKeyInit(&skey[1],
557 : Anum_pg_constraint_connamespace,
558 : BTEqualStrategyNumber, F_OIDEQ,
559 : ObjectIdGetDatum(namespaceid));
560 :
561 28526 : conscan = systable_beginscan(conDesc, ConstraintNameNspIndexId, true,
562 : NULL, 2, skey);
563 :
564 28526 : found = (HeapTupleIsValid(systable_getnext(conscan)));
565 :
566 28526 : systable_endscan(conscan);
567 : }
568 :
569 28544 : if (!found)
570 25344 : break;
571 :
572 : /* found a conflict, so try a new name component */
573 3200 : pfree(conname);
574 3200 : snprintf(modlabel, sizeof(modlabel), "%s%d", label, ++pass);
575 : }
576 :
577 25344 : table_close(conDesc, AccessShareLock);
578 :
579 25344 : return conname;
580 : }
581 :
582 : /*
583 : * Find and return a copy of the pg_constraint tuple that implements a
584 : * (possibly not valid) not-null constraint for the given column of the
585 : * given relation. If no such constraint exists, return NULL.
586 : *
587 : * XXX This would be easier if we had pg_attribute.notnullconstr with the OID
588 : * of the constraint that implements the not-null constraint for that column.
589 : * I'm not sure it's worth the catalog bloat and de-normalization, however.
590 : */
591 : HeapTuple
592 12374 : findNotNullConstraintAttnum(Oid relid, AttrNumber attnum)
593 : {
594 : Relation pg_constraint;
595 : HeapTuple conTup,
596 12374 : retval = NULL;
597 : SysScanDesc scan;
598 : ScanKeyData key;
599 :
600 12374 : pg_constraint = table_open(ConstraintRelationId, AccessShareLock);
601 12374 : ScanKeyInit(&key,
602 : Anum_pg_constraint_conrelid,
603 : BTEqualStrategyNumber, F_OIDEQ,
604 : ObjectIdGetDatum(relid));
605 12374 : scan = systable_beginscan(pg_constraint, ConstraintRelidTypidNameIndexId,
606 : true, NULL, 1, &key);
607 :
608 19876 : while (HeapTupleIsValid(conTup = systable_getnext(scan)))
609 : {
610 9010 : Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(conTup);
611 : AttrNumber conkey;
612 :
613 : /*
614 : * We're looking for a NOTNULL constraint with the column we're
615 : * looking for as the sole element in conkey.
616 : */
617 9010 : if (con->contype != CONSTRAINT_NOTNULL)
618 3350 : continue;
619 :
620 5660 : conkey = extractNotNullColumn(conTup);
621 5660 : if (conkey != attnum)
622 4152 : continue;
623 :
624 : /* Found it */
625 1508 : retval = heap_copytuple(conTup);
626 1508 : break;
627 : }
628 :
629 12374 : systable_endscan(scan);
630 12374 : table_close(pg_constraint, AccessShareLock);
631 :
632 12374 : return retval;
633 : }
634 :
635 : /*
636 : * Find and return a copy of the pg_constraint tuple that implements a
637 : * (possibly not valid) not-null constraint for the given column of the
638 : * given relation.
639 : * If no such column or no such constraint exists, return NULL.
640 : */
641 : HeapTuple
642 1320 : findNotNullConstraint(Oid relid, const char *colname)
643 : {
644 : AttrNumber attnum;
645 :
646 1320 : attnum = get_attnum(relid, colname);
647 1320 : if (attnum <= InvalidAttrNumber)
648 36 : return NULL;
649 :
650 1284 : return findNotNullConstraintAttnum(relid, attnum);
651 : }
652 :
653 : /*
654 : * Find and return the pg_constraint tuple that implements a validated
655 : * not-null constraint for the given domain.
656 : */
657 : HeapTuple
658 12 : findDomainNotNullConstraint(Oid typid)
659 : {
660 : Relation pg_constraint;
661 : HeapTuple conTup,
662 12 : retval = NULL;
663 : SysScanDesc scan;
664 : ScanKeyData key;
665 :
666 12 : pg_constraint = table_open(ConstraintRelationId, AccessShareLock);
667 12 : ScanKeyInit(&key,
668 : Anum_pg_constraint_contypid,
669 : BTEqualStrategyNumber, F_OIDEQ,
670 : ObjectIdGetDatum(typid));
671 12 : scan = systable_beginscan(pg_constraint, ConstraintRelidTypidNameIndexId,
672 : true, NULL, 1, &key);
673 :
674 12 : while (HeapTupleIsValid(conTup = systable_getnext(scan)))
675 : {
676 12 : Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(conTup);
677 :
678 : /*
679 : * We're looking for a NOTNULL constraint that's marked validated.
680 : */
681 12 : if (con->contype != CONSTRAINT_NOTNULL)
682 0 : continue;
683 12 : if (!con->convalidated)
684 0 : continue;
685 :
686 : /* Found it */
687 12 : retval = heap_copytuple(conTup);
688 12 : break;
689 : }
690 :
691 12 : systable_endscan(scan);
692 12 : table_close(pg_constraint, AccessShareLock);
693 :
694 12 : return retval;
695 : }
696 :
697 : /*
698 : * Given a pg_constraint tuple for a not-null constraint, return the column
699 : * number it is for.
700 : */
701 : AttrNumber
702 12614 : extractNotNullColumn(HeapTuple constrTup)
703 : {
704 : Datum adatum;
705 : ArrayType *arr;
706 :
707 : /* only tuples for not-null constraints should be given */
708 : Assert(((Form_pg_constraint) GETSTRUCT(constrTup))->contype == CONSTRAINT_NOTNULL);
709 :
710 12614 : adatum = SysCacheGetAttrNotNull(CONSTROID, constrTup,
711 : Anum_pg_constraint_conkey);
712 12614 : arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
713 12614 : if (ARR_NDIM(arr) != 1 ||
714 12614 : ARR_HASNULL(arr) ||
715 12614 : ARR_ELEMTYPE(arr) != INT2OID ||
716 12614 : ARR_DIMS(arr)[0] != 1)
717 0 : elog(ERROR, "conkey is not a 1-D smallint array");
718 :
719 : /* We leak the detoasted datum, but we don't care */
720 :
721 12614 : return ((AttrNumber *) ARR_DATA_PTR(arr))[0];
722 : }
723 :
724 : /*
725 : * AdjustNotNullInheritance
726 : * Adjust inheritance status for a single not-null constraint
727 : *
728 : * If no not-null constraint is found for the column, return false.
729 : * Caller can create one.
730 : *
731 : * If a constraint exists but the connoinherit flag is not what the caller
732 : * wants, throw an error about the incompatibility. If the desired
733 : * constraint is valid but the existing constraint is not valid, also
734 : * throw an error about that (the opposite case is acceptable).
735 : *
736 : * If everything checks out, we adjust conislocal/coninhcount and return
737 : * true. If is_local is true we flip conislocal true, or do nothing if
738 : * it's already true; otherwise we increment coninhcount by 1.
739 : */
740 : bool
741 9986 : AdjustNotNullInheritance(Oid relid, AttrNumber attnum,
742 : bool is_local, bool is_no_inherit, bool is_notvalid)
743 : {
744 : HeapTuple tup;
745 :
746 9986 : tup = findNotNullConstraintAttnum(relid, attnum);
747 9986 : if (HeapTupleIsValid(tup))
748 : {
749 : Relation pg_constraint;
750 : Form_pg_constraint conform;
751 136 : bool changed = false;
752 :
753 136 : pg_constraint = table_open(ConstraintRelationId, RowExclusiveLock);
754 136 : conform = (Form_pg_constraint) GETSTRUCT(tup);
755 :
756 : /*
757 : * If the NO INHERIT flag we're asked for doesn't match what the
758 : * existing constraint has, throw an error.
759 : */
760 136 : if (is_no_inherit != conform->connoinherit)
761 30 : ereport(ERROR,
762 : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
763 : errmsg("cannot change NO INHERIT status of NOT NULL constraint \"%s\" on relation \"%s\"",
764 : NameStr(conform->conname), get_rel_name(relid)),
765 : errhint("You might need to make the existing constraint inheritable using %s.",
766 : "ALTER TABLE ... ALTER CONSTRAINT ... INHERIT"));
767 :
768 : /*
769 : * Throw an error if the existing constraint is NOT VALID and caller
770 : * wants a valid one.
771 : */
772 106 : if (!is_notvalid && !conform->convalidated)
773 12 : ereport(ERROR,
774 : errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
775 : errmsg("incompatible NOT VALID constraint \"%s\" on relation \"%s\"",
776 : NameStr(conform->conname), get_rel_name(relid)),
777 : errhint("You might need to validate it using %s.",
778 : "ALTER TABLE ... VALIDATE CONSTRAINT"));
779 :
780 94 : if (!is_local)
781 : {
782 70 : if (pg_add_s16_overflow(conform->coninhcount, 1,
783 : &conform->coninhcount))
784 0 : ereport(ERROR,
785 : errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
786 : errmsg("too many inheritance parents"));
787 70 : changed = true;
788 : }
789 24 : else if (!conform->conislocal)
790 : {
791 0 : conform->conislocal = true;
792 0 : changed = true;
793 : }
794 :
795 94 : if (changed)
796 70 : CatalogTupleUpdate(pg_constraint, &tup->t_self, tup);
797 :
798 94 : table_close(pg_constraint, RowExclusiveLock);
799 :
800 94 : return true;
801 : }
802 :
803 9850 : return false;
804 : }
805 :
806 : /*
807 : * RelationGetNotNullConstraints
808 : * Return the list of not-null constraints for the given rel
809 : *
810 : * Caller can request cooked constraints, or raw.
811 : *
812 : * This is seldom needed, so we just scan pg_constraint each time.
813 : *
814 : * 'include_noinh' determines whether to include NO INHERIT constraints or not.
815 : */
816 : List *
817 10960 : RelationGetNotNullConstraints(Oid relid, bool cooked, bool include_noinh)
818 : {
819 10960 : List *notnulls = NIL;
820 : Relation constrRel;
821 : HeapTuple htup;
822 : SysScanDesc conscan;
823 : ScanKeyData skey;
824 :
825 10960 : constrRel = table_open(ConstraintRelationId, AccessShareLock);
826 10960 : ScanKeyInit(&skey,
827 : Anum_pg_constraint_conrelid,
828 : BTEqualStrategyNumber, F_OIDEQ,
829 : ObjectIdGetDatum(relid));
830 10960 : conscan = systable_beginscan(constrRel, ConstraintRelidTypidNameIndexId, true,
831 : NULL, 1, &skey);
832 :
833 17208 : while (HeapTupleIsValid(htup = systable_getnext(conscan)))
834 : {
835 6248 : Form_pg_constraint conForm = (Form_pg_constraint) GETSTRUCT(htup);
836 : AttrNumber colnum;
837 :
838 6248 : if (conForm->contype != CONSTRAINT_NOTNULL)
839 3390 : continue;
840 2858 : if (conForm->connoinherit && !include_noinh)
841 60 : continue;
842 :
843 2798 : colnum = extractNotNullColumn(htup);
844 :
845 2798 : if (cooked)
846 : {
847 : CookedConstraint *cooked;
848 :
849 2394 : cooked = (CookedConstraint *) palloc(sizeof(CookedConstraint));
850 :
851 2394 : cooked->contype = CONSTR_NOTNULL;
852 2394 : cooked->conoid = conForm->oid;
853 2394 : cooked->name = pstrdup(NameStr(conForm->conname));
854 2394 : cooked->attnum = colnum;
855 2394 : cooked->expr = NULL;
856 2394 : cooked->is_enforced = true;
857 2394 : cooked->skip_validation = !conForm->convalidated;
858 2394 : cooked->is_local = true;
859 2394 : cooked->inhcount = 0;
860 2394 : cooked->is_no_inherit = conForm->connoinherit;
861 :
862 2394 : notnulls = lappend(notnulls, cooked);
863 : }
864 : else
865 : {
866 : Constraint *constr;
867 :
868 404 : constr = makeNode(Constraint);
869 404 : constr->contype = CONSTR_NOTNULL;
870 404 : constr->conname = pstrdup(NameStr(conForm->conname));
871 404 : constr->deferrable = false;
872 404 : constr->initdeferred = false;
873 404 : constr->location = -1;
874 404 : constr->keys = list_make1(makeString(get_attname(relid, colnum,
875 : false)));
876 404 : constr->is_enforced = true;
877 404 : constr->skip_validation = !conForm->convalidated;
878 404 : constr->initially_valid = true;
879 404 : constr->is_no_inherit = conForm->connoinherit;
880 404 : notnulls = lappend(notnulls, constr);
881 : }
882 : }
883 :
884 10960 : systable_endscan(conscan);
885 10960 : table_close(constrRel, AccessShareLock);
886 :
887 10960 : return notnulls;
888 : }
889 :
890 :
891 : /*
892 : * Delete a single constraint record.
893 : */
894 : void
895 27692 : RemoveConstraintById(Oid conId)
896 : {
897 : Relation conDesc;
898 : HeapTuple tup;
899 : Form_pg_constraint con;
900 :
901 27692 : conDesc = table_open(ConstraintRelationId, RowExclusiveLock);
902 :
903 27692 : tup = SearchSysCache1(CONSTROID, ObjectIdGetDatum(conId));
904 27692 : if (!HeapTupleIsValid(tup)) /* should not happen */
905 0 : elog(ERROR, "cache lookup failed for constraint %u", conId);
906 27692 : con = (Form_pg_constraint) GETSTRUCT(tup);
907 :
908 : /*
909 : * Special processing depending on what the constraint is for.
910 : */
911 27692 : if (OidIsValid(con->conrelid))
912 : {
913 : Relation rel;
914 :
915 : /*
916 : * If the constraint is for a relation, open and exclusive-lock the
917 : * relation it's for.
918 : */
919 27334 : rel = table_open(con->conrelid, AccessExclusiveLock);
920 :
921 : /*
922 : * We need to update the relchecks count if it is a check constraint
923 : * being dropped. This update will force backends to rebuild relcache
924 : * entries when we commit.
925 : */
926 27332 : if (con->contype == CONSTRAINT_CHECK)
927 : {
928 : Relation pgrel;
929 : HeapTuple relTup;
930 : Form_pg_class classForm;
931 :
932 1942 : pgrel = table_open(RelationRelationId, RowExclusiveLock);
933 1942 : relTup = SearchSysCacheCopy1(RELOID,
934 : ObjectIdGetDatum(con->conrelid));
935 1942 : if (!HeapTupleIsValid(relTup))
936 0 : elog(ERROR, "cache lookup failed for relation %u",
937 : con->conrelid);
938 1942 : classForm = (Form_pg_class) GETSTRUCT(relTup);
939 :
940 1942 : if (classForm->relchecks > 0)
941 1942 : classForm->relchecks--;
942 : else
943 : /* should not happen */
944 0 : elog(WARNING, "relation \"%s\" has relchecks = %d",
945 : RelationGetRelationName(rel), classForm->relchecks);
946 :
947 1942 : CatalogTupleUpdate(pgrel, &relTup->t_self, relTup);
948 :
949 1942 : heap_freetuple(relTup);
950 :
951 1942 : table_close(pgrel, RowExclusiveLock);
952 : }
953 :
954 : /* Keep lock on constraint's rel until end of xact */
955 27332 : table_close(rel, NoLock);
956 : }
957 358 : else if (OidIsValid(con->contypid))
958 : {
959 : /*
960 : * XXX for now, do nothing special when dropping a domain constraint
961 : *
962 : * Probably there should be some form of locking on the domain type,
963 : * but we have no such concept at the moment.
964 : */
965 : }
966 : else
967 0 : elog(ERROR, "constraint %u is not of a known type", conId);
968 :
969 : /* Fry the constraint itself */
970 27690 : CatalogTupleDelete(conDesc, &tup->t_self);
971 :
972 : /* Clean up */
973 27690 : ReleaseSysCache(tup);
974 27690 : table_close(conDesc, RowExclusiveLock);
975 27690 : }
976 :
977 : /*
978 : * RenameConstraintById
979 : * Rename a constraint.
980 : *
981 : * Note: this isn't intended to be a user-exposed function; it doesn't check
982 : * permissions etc. Currently this is only invoked when renaming an index
983 : * that is associated with a constraint, but it's made a little more general
984 : * than that with the expectation of someday having ALTER TABLE RENAME
985 : * CONSTRAINT.
986 : */
987 : void
988 96 : RenameConstraintById(Oid conId, const char *newname)
989 : {
990 : Relation conDesc;
991 : HeapTuple tuple;
992 : Form_pg_constraint con;
993 :
994 96 : conDesc = table_open(ConstraintRelationId, RowExclusiveLock);
995 :
996 96 : tuple = SearchSysCacheCopy1(CONSTROID, ObjectIdGetDatum(conId));
997 96 : if (!HeapTupleIsValid(tuple))
998 0 : elog(ERROR, "cache lookup failed for constraint %u", conId);
999 96 : con = (Form_pg_constraint) GETSTRUCT(tuple);
1000 :
1001 : /*
1002 : * For user-friendliness, check whether the name is already in use.
1003 : */
1004 186 : if (OidIsValid(con->conrelid) &&
1005 90 : ConstraintNameIsUsed(CONSTRAINT_RELATION,
1006 : con->conrelid,
1007 : newname))
1008 0 : ereport(ERROR,
1009 : (errcode(ERRCODE_DUPLICATE_OBJECT),
1010 : errmsg("constraint \"%s\" for relation \"%s\" already exists",
1011 : newname, get_rel_name(con->conrelid))));
1012 102 : if (OidIsValid(con->contypid) &&
1013 6 : ConstraintNameIsUsed(CONSTRAINT_DOMAIN,
1014 : con->contypid,
1015 : newname))
1016 0 : ereport(ERROR,
1017 : (errcode(ERRCODE_DUPLICATE_OBJECT),
1018 : errmsg("constraint \"%s\" for domain %s already exists",
1019 : newname, format_type_be(con->contypid))));
1020 :
1021 : /* OK, do the rename --- tuple is a copy, so OK to scribble on it */
1022 96 : namestrcpy(&(con->conname), newname);
1023 :
1024 96 : CatalogTupleUpdate(conDesc, &tuple->t_self, tuple);
1025 :
1026 96 : InvokeObjectPostAlterHook(ConstraintRelationId, conId, 0);
1027 :
1028 96 : heap_freetuple(tuple);
1029 96 : table_close(conDesc, RowExclusiveLock);
1030 96 : }
1031 :
1032 : /*
1033 : * AlterConstraintNamespaces
1034 : * Find any constraints belonging to the specified object,
1035 : * and move them to the specified new namespace.
1036 : *
1037 : * isType indicates whether the owning object is a type or a relation.
1038 : */
1039 : void
1040 106 : AlterConstraintNamespaces(Oid ownerId, Oid oldNspId,
1041 : Oid newNspId, bool isType, ObjectAddresses *objsMoved)
1042 : {
1043 : Relation conRel;
1044 : ScanKeyData key[2];
1045 : SysScanDesc scan;
1046 : HeapTuple tup;
1047 :
1048 106 : conRel = table_open(ConstraintRelationId, RowExclusiveLock);
1049 :
1050 106 : ScanKeyInit(&key[0],
1051 : Anum_pg_constraint_conrelid,
1052 : BTEqualStrategyNumber, F_OIDEQ,
1053 : ObjectIdGetDatum(isType ? InvalidOid : ownerId));
1054 106 : ScanKeyInit(&key[1],
1055 : Anum_pg_constraint_contypid,
1056 : BTEqualStrategyNumber, F_OIDEQ,
1057 : ObjectIdGetDatum(isType ? ownerId : InvalidOid));
1058 :
1059 106 : scan = systable_beginscan(conRel, ConstraintRelidTypidNameIndexId, true,
1060 : NULL, 2, key);
1061 :
1062 258 : while (HeapTupleIsValid((tup = systable_getnext(scan))))
1063 : {
1064 152 : Form_pg_constraint conform = (Form_pg_constraint) GETSTRUCT(tup);
1065 : ObjectAddress thisobj;
1066 :
1067 152 : ObjectAddressSet(thisobj, ConstraintRelationId, conform->oid);
1068 :
1069 152 : if (object_address_present(&thisobj, objsMoved))
1070 0 : continue;
1071 :
1072 : /* Don't update if the object is already part of the namespace */
1073 152 : if (conform->connamespace == oldNspId && oldNspId != newNspId)
1074 : {
1075 122 : tup = heap_copytuple(tup);
1076 122 : conform = (Form_pg_constraint) GETSTRUCT(tup);
1077 :
1078 122 : conform->connamespace = newNspId;
1079 :
1080 122 : CatalogTupleUpdate(conRel, &tup->t_self, tup);
1081 :
1082 : /*
1083 : * Note: currently, the constraint will not have its own
1084 : * dependency on the namespace, so we don't need to do
1085 : * changeDependencyFor().
1086 : */
1087 : }
1088 :
1089 152 : InvokeObjectPostAlterHook(ConstraintRelationId, thisobj.objectId, 0);
1090 :
1091 152 : add_exact_object_address(&thisobj, objsMoved);
1092 : }
1093 :
1094 106 : systable_endscan(scan);
1095 :
1096 106 : table_close(conRel, RowExclusiveLock);
1097 106 : }
1098 :
1099 : /*
1100 : * ConstraintSetParentConstraint
1101 : * Set a partition's constraint as child of its parent constraint,
1102 : * or remove the linkage if parentConstrId is InvalidOid.
1103 : *
1104 : * This updates the constraint's pg_constraint row to show it as inherited, and
1105 : * adds PARTITION dependencies to prevent the constraint from being deleted
1106 : * on its own. Alternatively, reverse that.
1107 : */
1108 : void
1109 642 : ConstraintSetParentConstraint(Oid childConstrId,
1110 : Oid parentConstrId,
1111 : Oid childTableId)
1112 : {
1113 : Relation constrRel;
1114 : Form_pg_constraint constrForm;
1115 : HeapTuple tuple,
1116 : newtup;
1117 : ObjectAddress depender;
1118 : ObjectAddress referenced;
1119 :
1120 642 : constrRel = table_open(ConstraintRelationId, RowExclusiveLock);
1121 642 : tuple = SearchSysCache1(CONSTROID, ObjectIdGetDatum(childConstrId));
1122 642 : if (!HeapTupleIsValid(tuple))
1123 0 : elog(ERROR, "cache lookup failed for constraint %u", childConstrId);
1124 642 : newtup = heap_copytuple(tuple);
1125 642 : constrForm = (Form_pg_constraint) GETSTRUCT(newtup);
1126 642 : if (OidIsValid(parentConstrId))
1127 : {
1128 : /* don't allow setting parent for a constraint that already has one */
1129 : Assert(constrForm->coninhcount == 0);
1130 394 : if (constrForm->conparentid != InvalidOid)
1131 0 : elog(ERROR, "constraint %u already has a parent constraint",
1132 : childConstrId);
1133 :
1134 394 : constrForm->conislocal = false;
1135 394 : if (pg_add_s16_overflow(constrForm->coninhcount, 1,
1136 : &constrForm->coninhcount))
1137 0 : ereport(ERROR,
1138 : errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
1139 : errmsg("too many inheritance parents"));
1140 :
1141 394 : constrForm->conparentid = parentConstrId;
1142 :
1143 394 : CatalogTupleUpdate(constrRel, &tuple->t_self, newtup);
1144 :
1145 394 : ObjectAddressSet(depender, ConstraintRelationId, childConstrId);
1146 :
1147 394 : ObjectAddressSet(referenced, ConstraintRelationId, parentConstrId);
1148 394 : recordDependencyOn(&depender, &referenced, DEPENDENCY_PARTITION_PRI);
1149 :
1150 394 : ObjectAddressSet(referenced, RelationRelationId, childTableId);
1151 394 : recordDependencyOn(&depender, &referenced, DEPENDENCY_PARTITION_SEC);
1152 : }
1153 : else
1154 : {
1155 248 : constrForm->coninhcount--;
1156 248 : constrForm->conislocal = true;
1157 248 : constrForm->conparentid = InvalidOid;
1158 :
1159 : /* Make sure there's no further inheritance. */
1160 : Assert(constrForm->coninhcount == 0);
1161 :
1162 248 : CatalogTupleUpdate(constrRel, &tuple->t_self, newtup);
1163 :
1164 248 : deleteDependencyRecordsForClass(ConstraintRelationId, childConstrId,
1165 : ConstraintRelationId,
1166 : DEPENDENCY_PARTITION_PRI);
1167 248 : deleteDependencyRecordsForClass(ConstraintRelationId, childConstrId,
1168 : RelationRelationId,
1169 : DEPENDENCY_PARTITION_SEC);
1170 : }
1171 :
1172 642 : ReleaseSysCache(tuple);
1173 642 : table_close(constrRel, RowExclusiveLock);
1174 642 : }
1175 :
1176 :
1177 : /*
1178 : * get_relation_constraint_oid
1179 : * Find a constraint on the specified relation with the specified name.
1180 : * Returns constraint's OID.
1181 : */
1182 : Oid
1183 564 : get_relation_constraint_oid(Oid relid, const char *conname, bool missing_ok)
1184 : {
1185 : Relation pg_constraint;
1186 : HeapTuple tuple;
1187 : SysScanDesc scan;
1188 : ScanKeyData skey[3];
1189 564 : Oid conOid = InvalidOid;
1190 :
1191 564 : pg_constraint = table_open(ConstraintRelationId, AccessShareLock);
1192 :
1193 564 : ScanKeyInit(&skey[0],
1194 : Anum_pg_constraint_conrelid,
1195 : BTEqualStrategyNumber, F_OIDEQ,
1196 : ObjectIdGetDatum(relid));
1197 564 : ScanKeyInit(&skey[1],
1198 : Anum_pg_constraint_contypid,
1199 : BTEqualStrategyNumber, F_OIDEQ,
1200 : ObjectIdGetDatum(InvalidOid));
1201 564 : ScanKeyInit(&skey[2],
1202 : Anum_pg_constraint_conname,
1203 : BTEqualStrategyNumber, F_NAMEEQ,
1204 : CStringGetDatum(conname));
1205 :
1206 564 : scan = systable_beginscan(pg_constraint, ConstraintRelidTypidNameIndexId, true,
1207 : NULL, 3, skey);
1208 :
1209 : /* There can be at most one matching row */
1210 564 : if (HeapTupleIsValid(tuple = systable_getnext(scan)))
1211 552 : conOid = ((Form_pg_constraint) GETSTRUCT(tuple))->oid;
1212 :
1213 564 : systable_endscan(scan);
1214 :
1215 : /* If no such constraint exists, complain */
1216 564 : if (!OidIsValid(conOid) && !missing_ok)
1217 12 : ereport(ERROR,
1218 : (errcode(ERRCODE_UNDEFINED_OBJECT),
1219 : errmsg("constraint \"%s\" for table \"%s\" does not exist",
1220 : conname, get_rel_name(relid))));
1221 :
1222 552 : table_close(pg_constraint, AccessShareLock);
1223 :
1224 552 : return conOid;
1225 : }
1226 :
1227 : /*
1228 : * get_relation_constraint_attnos
1229 : * Find a constraint on the specified relation with the specified name
1230 : * and return the constrained columns.
1231 : *
1232 : * Returns a Bitmapset of the column attnos of the constrained columns, with
1233 : * attnos being offset by FirstLowInvalidHeapAttributeNumber so that system
1234 : * columns can be represented.
1235 : *
1236 : * *constraintOid is set to the OID of the constraint, or InvalidOid on
1237 : * failure.
1238 : */
1239 : Bitmapset *
1240 192 : get_relation_constraint_attnos(Oid relid, const char *conname,
1241 : bool missing_ok, Oid *constraintOid)
1242 : {
1243 192 : Bitmapset *conattnos = NULL;
1244 : Relation pg_constraint;
1245 : HeapTuple tuple;
1246 : SysScanDesc scan;
1247 : ScanKeyData skey[3];
1248 :
1249 : /* Set *constraintOid, to avoid complaints about uninitialized vars */
1250 192 : *constraintOid = InvalidOid;
1251 :
1252 192 : pg_constraint = table_open(ConstraintRelationId, AccessShareLock);
1253 :
1254 192 : ScanKeyInit(&skey[0],
1255 : Anum_pg_constraint_conrelid,
1256 : BTEqualStrategyNumber, F_OIDEQ,
1257 : ObjectIdGetDatum(relid));
1258 192 : ScanKeyInit(&skey[1],
1259 : Anum_pg_constraint_contypid,
1260 : BTEqualStrategyNumber, F_OIDEQ,
1261 : ObjectIdGetDatum(InvalidOid));
1262 192 : ScanKeyInit(&skey[2],
1263 : Anum_pg_constraint_conname,
1264 : BTEqualStrategyNumber, F_NAMEEQ,
1265 : CStringGetDatum(conname));
1266 :
1267 192 : scan = systable_beginscan(pg_constraint, ConstraintRelidTypidNameIndexId, true,
1268 : NULL, 3, skey);
1269 :
1270 : /* There can be at most one matching row */
1271 192 : if (HeapTupleIsValid(tuple = systable_getnext(scan)))
1272 : {
1273 : Datum adatum;
1274 : bool isNull;
1275 :
1276 192 : *constraintOid = ((Form_pg_constraint) GETSTRUCT(tuple))->oid;
1277 :
1278 : /* Extract the conkey array, ie, attnums of constrained columns */
1279 192 : adatum = heap_getattr(tuple, Anum_pg_constraint_conkey,
1280 : RelationGetDescr(pg_constraint), &isNull);
1281 192 : if (!isNull)
1282 : {
1283 : ArrayType *arr;
1284 : int numcols;
1285 : int16 *attnums;
1286 : int i;
1287 :
1288 192 : arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
1289 192 : numcols = ARR_DIMS(arr)[0];
1290 192 : if (ARR_NDIM(arr) != 1 ||
1291 192 : numcols < 0 ||
1292 192 : ARR_HASNULL(arr) ||
1293 192 : ARR_ELEMTYPE(arr) != INT2OID)
1294 0 : elog(ERROR, "conkey is not a 1-D smallint array");
1295 192 : attnums = (int16 *) ARR_DATA_PTR(arr);
1296 :
1297 : /* Construct the result value */
1298 540 : for (i = 0; i < numcols; i++)
1299 : {
1300 348 : conattnos = bms_add_member(conattnos,
1301 348 : attnums[i] - FirstLowInvalidHeapAttributeNumber);
1302 : }
1303 : }
1304 : }
1305 :
1306 192 : systable_endscan(scan);
1307 :
1308 : /* If no such constraint exists, complain */
1309 192 : if (!OidIsValid(*constraintOid) && !missing_ok)
1310 0 : ereport(ERROR,
1311 : (errcode(ERRCODE_UNDEFINED_OBJECT),
1312 : errmsg("constraint \"%s\" for table \"%s\" does not exist",
1313 : conname, get_rel_name(relid))));
1314 :
1315 192 : table_close(pg_constraint, AccessShareLock);
1316 :
1317 192 : return conattnos;
1318 : }
1319 :
1320 : /*
1321 : * Return the OID of the constraint enforced by the given index in the
1322 : * given relation; or InvalidOid if no such index is cataloged.
1323 : *
1324 : * Much like get_constraint_index, this function is concerned only with the
1325 : * one constraint that "owns" the given index. Therefore, constraints of
1326 : * types other than unique, primary-key, and exclusion are ignored.
1327 : */
1328 : Oid
1329 1348 : get_relation_idx_constraint_oid(Oid relationId, Oid indexId)
1330 : {
1331 : Relation pg_constraint;
1332 : SysScanDesc scan;
1333 : ScanKeyData key;
1334 : HeapTuple tuple;
1335 1348 : Oid constraintId = InvalidOid;
1336 :
1337 1348 : pg_constraint = table_open(ConstraintRelationId, AccessShareLock);
1338 :
1339 1348 : ScanKeyInit(&key,
1340 : Anum_pg_constraint_conrelid,
1341 : BTEqualStrategyNumber,
1342 : F_OIDEQ,
1343 : ObjectIdGetDatum(relationId));
1344 1348 : scan = systable_beginscan(pg_constraint, ConstraintRelidTypidNameIndexId,
1345 : true, NULL, 1, &key);
1346 2588 : while ((tuple = systable_getnext(scan)) != NULL)
1347 : {
1348 : Form_pg_constraint constrForm;
1349 :
1350 2026 : constrForm = (Form_pg_constraint) GETSTRUCT(tuple);
1351 :
1352 : /* See above */
1353 2026 : if (constrForm->contype != CONSTRAINT_PRIMARY &&
1354 1296 : constrForm->contype != CONSTRAINT_UNIQUE &&
1355 1224 : constrForm->contype != CONSTRAINT_EXCLUSION)
1356 1224 : continue;
1357 :
1358 802 : if (constrForm->conindid == indexId)
1359 : {
1360 786 : constraintId = constrForm->oid;
1361 786 : break;
1362 : }
1363 : }
1364 1348 : systable_endscan(scan);
1365 :
1366 1348 : table_close(pg_constraint, AccessShareLock);
1367 1348 : return constraintId;
1368 : }
1369 :
1370 : /*
1371 : * get_domain_constraint_oid
1372 : * Find a constraint on the specified domain with the specified name.
1373 : * Returns constraint's OID.
1374 : */
1375 : Oid
1376 68 : get_domain_constraint_oid(Oid typid, const char *conname, bool missing_ok)
1377 : {
1378 : Relation pg_constraint;
1379 : HeapTuple tuple;
1380 : SysScanDesc scan;
1381 : ScanKeyData skey[3];
1382 68 : Oid conOid = InvalidOid;
1383 :
1384 68 : pg_constraint = table_open(ConstraintRelationId, AccessShareLock);
1385 :
1386 68 : ScanKeyInit(&skey[0],
1387 : Anum_pg_constraint_conrelid,
1388 : BTEqualStrategyNumber, F_OIDEQ,
1389 : ObjectIdGetDatum(InvalidOid));
1390 68 : ScanKeyInit(&skey[1],
1391 : Anum_pg_constraint_contypid,
1392 : BTEqualStrategyNumber, F_OIDEQ,
1393 : ObjectIdGetDatum(typid));
1394 68 : ScanKeyInit(&skey[2],
1395 : Anum_pg_constraint_conname,
1396 : BTEqualStrategyNumber, F_NAMEEQ,
1397 : CStringGetDatum(conname));
1398 :
1399 68 : scan = systable_beginscan(pg_constraint, ConstraintRelidTypidNameIndexId, true,
1400 : NULL, 3, skey);
1401 :
1402 : /* There can be at most one matching row */
1403 68 : if (HeapTupleIsValid(tuple = systable_getnext(scan)))
1404 62 : conOid = ((Form_pg_constraint) GETSTRUCT(tuple))->oid;
1405 :
1406 68 : systable_endscan(scan);
1407 :
1408 : /* If no such constraint exists, complain */
1409 68 : if (!OidIsValid(conOid) && !missing_ok)
1410 6 : ereport(ERROR,
1411 : (errcode(ERRCODE_UNDEFINED_OBJECT),
1412 : errmsg("constraint \"%s\" for domain %s does not exist",
1413 : conname, format_type_be(typid))));
1414 :
1415 62 : table_close(pg_constraint, AccessShareLock);
1416 :
1417 62 : return conOid;
1418 : }
1419 :
1420 : /*
1421 : * get_primary_key_attnos
1422 : * Identify the columns in a relation's primary key, if any.
1423 : *
1424 : * Returns a Bitmapset of the column attnos of the primary key's columns,
1425 : * with attnos being offset by FirstLowInvalidHeapAttributeNumber so that
1426 : * system columns can be represented.
1427 : *
1428 : * If there is no primary key, return NULL. We also return NULL if the pkey
1429 : * constraint is deferrable and deferrableOk is false.
1430 : *
1431 : * *constraintOid is set to the OID of the pkey constraint, or InvalidOid
1432 : * on failure.
1433 : */
1434 : Bitmapset *
1435 404 : get_primary_key_attnos(Oid relid, bool deferrableOk, Oid *constraintOid)
1436 : {
1437 404 : Bitmapset *pkattnos = NULL;
1438 : Relation pg_constraint;
1439 : HeapTuple tuple;
1440 : SysScanDesc scan;
1441 : ScanKeyData skey[1];
1442 :
1443 : /* Set *constraintOid, to avoid complaints about uninitialized vars */
1444 404 : *constraintOid = InvalidOid;
1445 :
1446 : /* Scan pg_constraint for constraints of the target rel */
1447 404 : pg_constraint = table_open(ConstraintRelationId, AccessShareLock);
1448 :
1449 404 : ScanKeyInit(&skey[0],
1450 : Anum_pg_constraint_conrelid,
1451 : BTEqualStrategyNumber, F_OIDEQ,
1452 : ObjectIdGetDatum(relid));
1453 :
1454 404 : scan = systable_beginscan(pg_constraint, ConstraintRelidTypidNameIndexId, true,
1455 : NULL, 1, skey);
1456 :
1457 706 : while (HeapTupleIsValid(tuple = systable_getnext(scan)))
1458 : {
1459 658 : Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(tuple);
1460 : Datum adatum;
1461 : bool isNull;
1462 : ArrayType *arr;
1463 : int16 *attnums;
1464 : int numkeys;
1465 : int i;
1466 :
1467 : /* Skip constraints that are not PRIMARY KEYs */
1468 658 : if (con->contype != CONSTRAINT_PRIMARY)
1469 302 : continue;
1470 :
1471 : /*
1472 : * If the primary key is deferrable, but we've been instructed to
1473 : * ignore deferrable constraints, then we might as well give up
1474 : * searching, since there can only be a single primary key on a table.
1475 : */
1476 356 : if (con->condeferrable && !deferrableOk)
1477 356 : break;
1478 :
1479 : /* Extract the conkey array, ie, attnums of PK's columns */
1480 356 : adatum = heap_getattr(tuple, Anum_pg_constraint_conkey,
1481 : RelationGetDescr(pg_constraint), &isNull);
1482 356 : if (isNull)
1483 0 : elog(ERROR, "null conkey for constraint %u",
1484 : ((Form_pg_constraint) GETSTRUCT(tuple))->oid);
1485 356 : arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
1486 356 : numkeys = ARR_DIMS(arr)[0];
1487 356 : if (ARR_NDIM(arr) != 1 ||
1488 356 : numkeys < 0 ||
1489 356 : ARR_HASNULL(arr) ||
1490 356 : ARR_ELEMTYPE(arr) != INT2OID)
1491 0 : elog(ERROR, "conkey is not a 1-D smallint array");
1492 356 : attnums = (int16 *) ARR_DATA_PTR(arr);
1493 :
1494 : /* Construct the result value */
1495 730 : for (i = 0; i < numkeys; i++)
1496 : {
1497 374 : pkattnos = bms_add_member(pkattnos,
1498 374 : attnums[i] - FirstLowInvalidHeapAttributeNumber);
1499 : }
1500 356 : *constraintOid = ((Form_pg_constraint) GETSTRUCT(tuple))->oid;
1501 :
1502 : /* No need to search further */
1503 356 : break;
1504 : }
1505 :
1506 404 : systable_endscan(scan);
1507 :
1508 404 : table_close(pg_constraint, AccessShareLock);
1509 :
1510 404 : return pkattnos;
1511 : }
1512 :
1513 : /*
1514 : * Extract data from the pg_constraint tuple of a foreign-key constraint.
1515 : *
1516 : * All arguments save the first are output arguments. All output arguments
1517 : * other than numfks, conkey and confkey can be passed as NULL if caller
1518 : * doesn't need them.
1519 : */
1520 : void
1521 8966 : DeconstructFkConstraintRow(HeapTuple tuple, int *numfks,
1522 : AttrNumber *conkey, AttrNumber *confkey,
1523 : Oid *pf_eq_oprs, Oid *pp_eq_oprs, Oid *ff_eq_oprs,
1524 : int *num_fk_del_set_cols, AttrNumber *fk_del_set_cols)
1525 : {
1526 : Datum adatum;
1527 : bool isNull;
1528 : ArrayType *arr;
1529 : int numkeys;
1530 :
1531 : /*
1532 : * We expect the arrays to be 1-D arrays of the right types; verify that.
1533 : * We don't need to use deconstruct_array() since the array data is just
1534 : * going to look like a C array of values.
1535 : */
1536 8966 : adatum = SysCacheGetAttrNotNull(CONSTROID, tuple,
1537 : Anum_pg_constraint_conkey);
1538 8966 : arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
1539 8966 : if (ARR_NDIM(arr) != 1 ||
1540 8966 : ARR_HASNULL(arr) ||
1541 8966 : ARR_ELEMTYPE(arr) != INT2OID)
1542 0 : elog(ERROR, "conkey is not a 1-D smallint array");
1543 8966 : numkeys = ARR_DIMS(arr)[0];
1544 8966 : if (numkeys <= 0 || numkeys > INDEX_MAX_KEYS)
1545 0 : elog(ERROR, "foreign key constraint cannot have %d columns", numkeys);
1546 8966 : memcpy(conkey, ARR_DATA_PTR(arr), numkeys * sizeof(int16));
1547 8966 : if ((Pointer) arr != DatumGetPointer(adatum))
1548 8966 : pfree(arr); /* free de-toasted copy, if any */
1549 :
1550 8966 : adatum = SysCacheGetAttrNotNull(CONSTROID, tuple,
1551 : Anum_pg_constraint_confkey);
1552 8966 : arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
1553 8966 : if (ARR_NDIM(arr) != 1 ||
1554 8966 : ARR_DIMS(arr)[0] != numkeys ||
1555 8966 : ARR_HASNULL(arr) ||
1556 8966 : ARR_ELEMTYPE(arr) != INT2OID)
1557 0 : elog(ERROR, "confkey is not a 1-D smallint array");
1558 8966 : memcpy(confkey, ARR_DATA_PTR(arr), numkeys * sizeof(int16));
1559 8966 : if ((Pointer) arr != DatumGetPointer(adatum))
1560 8966 : pfree(arr); /* free de-toasted copy, if any */
1561 :
1562 8966 : if (pf_eq_oprs)
1563 : {
1564 8966 : adatum = SysCacheGetAttrNotNull(CONSTROID, tuple,
1565 : Anum_pg_constraint_conpfeqop);
1566 8966 : arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
1567 : /* see TryReuseForeignKey if you change the test below */
1568 8966 : if (ARR_NDIM(arr) != 1 ||
1569 8966 : ARR_DIMS(arr)[0] != numkeys ||
1570 8966 : ARR_HASNULL(arr) ||
1571 8966 : ARR_ELEMTYPE(arr) != OIDOID)
1572 0 : elog(ERROR, "conpfeqop is not a 1-D Oid array");
1573 8966 : memcpy(pf_eq_oprs, ARR_DATA_PTR(arr), numkeys * sizeof(Oid));
1574 8966 : if ((Pointer) arr != DatumGetPointer(adatum))
1575 8966 : pfree(arr); /* free de-toasted copy, if any */
1576 : }
1577 :
1578 8966 : if (pp_eq_oprs)
1579 : {
1580 5258 : adatum = SysCacheGetAttrNotNull(CONSTROID, tuple,
1581 : Anum_pg_constraint_conppeqop);
1582 5258 : arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
1583 5258 : if (ARR_NDIM(arr) != 1 ||
1584 5258 : ARR_DIMS(arr)[0] != numkeys ||
1585 5258 : ARR_HASNULL(arr) ||
1586 5258 : ARR_ELEMTYPE(arr) != OIDOID)
1587 0 : elog(ERROR, "conppeqop is not a 1-D Oid array");
1588 5258 : memcpy(pp_eq_oprs, ARR_DATA_PTR(arr), numkeys * sizeof(Oid));
1589 5258 : if ((Pointer) arr != DatumGetPointer(adatum))
1590 5258 : pfree(arr); /* free de-toasted copy, if any */
1591 : }
1592 :
1593 8966 : if (ff_eq_oprs)
1594 : {
1595 5258 : adatum = SysCacheGetAttrNotNull(CONSTROID, tuple,
1596 : Anum_pg_constraint_conffeqop);
1597 5258 : arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
1598 5258 : if (ARR_NDIM(arr) != 1 ||
1599 5258 : ARR_DIMS(arr)[0] != numkeys ||
1600 5258 : ARR_HASNULL(arr) ||
1601 5258 : ARR_ELEMTYPE(arr) != OIDOID)
1602 0 : elog(ERROR, "conffeqop is not a 1-D Oid array");
1603 5258 : memcpy(ff_eq_oprs, ARR_DATA_PTR(arr), numkeys * sizeof(Oid));
1604 5258 : if ((Pointer) arr != DatumGetPointer(adatum))
1605 5258 : pfree(arr); /* free de-toasted copy, if any */
1606 : }
1607 :
1608 8966 : if (fk_del_set_cols)
1609 : {
1610 5258 : adatum = SysCacheGetAttr(CONSTROID, tuple,
1611 : Anum_pg_constraint_confdelsetcols, &isNull);
1612 5258 : if (isNull)
1613 : {
1614 5180 : *num_fk_del_set_cols = 0;
1615 : }
1616 : else
1617 : {
1618 : int num_delete_cols;
1619 :
1620 78 : arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
1621 78 : if (ARR_NDIM(arr) != 1 ||
1622 78 : ARR_HASNULL(arr) ||
1623 78 : ARR_ELEMTYPE(arr) != INT2OID)
1624 0 : elog(ERROR, "confdelsetcols is not a 1-D smallint array");
1625 78 : num_delete_cols = ARR_DIMS(arr)[0];
1626 78 : memcpy(fk_del_set_cols, ARR_DATA_PTR(arr), num_delete_cols * sizeof(int16));
1627 78 : if ((Pointer) arr != DatumGetPointer(adatum))
1628 78 : pfree(arr); /* free de-toasted copy, if any */
1629 :
1630 78 : *num_fk_del_set_cols = num_delete_cols;
1631 : }
1632 : }
1633 :
1634 8966 : *numfks = numkeys;
1635 8966 : }
1636 :
1637 : /*
1638 : * FindFKPeriodOpers -
1639 : *
1640 : * Looks up the operator oids used for the PERIOD part of a temporal foreign key.
1641 : * The opclass should be the opclass of that PERIOD element.
1642 : * Everything else is an output: containedbyoperoid is the ContainedBy operator for
1643 : * types matching the PERIOD element.
1644 : * aggedcontainedbyoperoid is also a ContainedBy operator,
1645 : * but one whose rhs is a multirange.
1646 : * That way foreign keys can compare fkattr <@ range_agg(pkattr).
1647 : * intersectoperoid is used by NO ACTION constraints to trim the range being considered
1648 : * to just what was updated/deleted.
1649 : */
1650 : void
1651 412 : FindFKPeriodOpers(Oid opclass,
1652 : Oid *containedbyoperoid,
1653 : Oid *aggedcontainedbyoperoid,
1654 : Oid *intersectoperoid)
1655 : {
1656 412 : Oid opfamily = InvalidOid;
1657 412 : Oid opcintype = InvalidOid;
1658 : StrategyNumber strat;
1659 :
1660 : /* Make sure we have a range or multirange. */
1661 412 : if (get_opclass_opfamily_and_input_type(opclass, &opfamily, &opcintype))
1662 : {
1663 412 : if (opcintype != ANYRANGEOID && opcintype != ANYMULTIRANGEOID)
1664 0 : ereport(ERROR,
1665 : errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1666 : errmsg("invalid type for PERIOD part of foreign key"),
1667 : errdetail("Only range and multirange are supported."));
1668 :
1669 : }
1670 : else
1671 0 : elog(ERROR, "cache lookup failed for opclass %u", opclass);
1672 :
1673 : /*
1674 : * Look up the ContainedBy operator whose lhs and rhs are the opclass's
1675 : * type. We use this to optimize RI checks: if the new value includes all
1676 : * of the old value, then we can treat the attribute as if it didn't
1677 : * change, and skip the RI check.
1678 : */
1679 412 : GetOperatorFromCompareType(opclass,
1680 : InvalidOid,
1681 : COMPARE_CONTAINED_BY,
1682 : containedbyoperoid,
1683 : &strat);
1684 :
1685 : /*
1686 : * Now look up the ContainedBy operator. Its left arg must be the type of
1687 : * the column (or rather of the opclass). Its right arg must match the
1688 : * return type of the support proc.
1689 : */
1690 412 : GetOperatorFromCompareType(opclass,
1691 : ANYMULTIRANGEOID,
1692 : COMPARE_CONTAINED_BY,
1693 : aggedcontainedbyoperoid,
1694 : &strat);
1695 :
1696 412 : switch (opcintype)
1697 : {
1698 270 : case ANYRANGEOID:
1699 270 : *intersectoperoid = OID_RANGE_INTERSECT_RANGE_OP;
1700 270 : break;
1701 142 : case ANYMULTIRANGEOID:
1702 142 : *intersectoperoid = OID_MULTIRANGE_INTERSECT_MULTIRANGE_OP;
1703 142 : break;
1704 0 : default:
1705 0 : elog(ERROR, "unexpected opcintype: %u", opcintype);
1706 : }
1707 412 : }
1708 :
1709 : /*
1710 : * Determine whether a relation can be proven functionally dependent on
1711 : * a set of grouping columns. If so, return true and add the pg_constraint
1712 : * OIDs of the constraints needed for the proof to the *constraintDeps list.
1713 : *
1714 : * grouping_columns is a list of grouping expressions, in which columns of
1715 : * the rel of interest are Vars with the indicated varno/varlevelsup.
1716 : *
1717 : * Currently we only check to see if the rel has a primary key that is a
1718 : * subset of the grouping_columns. We could also use plain unique constraints
1719 : * if all their columns are known not null, but there's a problem: we need
1720 : * to be able to represent the not-null-ness as part of the constraints added
1721 : * to *constraintDeps. FIXME whenever not-null constraints get represented
1722 : * in pg_constraint.
1723 : */
1724 : bool
1725 404 : check_functional_grouping(Oid relid,
1726 : Index varno, Index varlevelsup,
1727 : List *grouping_columns,
1728 : List **constraintDeps)
1729 : {
1730 : Bitmapset *pkattnos;
1731 : Bitmapset *groupbyattnos;
1732 : Oid constraintOid;
1733 : ListCell *gl;
1734 :
1735 : /* If the rel has no PK, then we can't prove functional dependency */
1736 404 : pkattnos = get_primary_key_attnos(relid, false, &constraintOid);
1737 404 : if (pkattnos == NULL)
1738 48 : return false;
1739 :
1740 : /* Identify all the rel's columns that appear in grouping_columns */
1741 356 : groupbyattnos = NULL;
1742 796 : foreach(gl, grouping_columns)
1743 : {
1744 440 : Var *gvar = (Var *) lfirst(gl);
1745 :
1746 440 : if (IsA(gvar, Var) &&
1747 440 : gvar->varno == varno &&
1748 278 : gvar->varlevelsup == varlevelsup)
1749 278 : groupbyattnos = bms_add_member(groupbyattnos,
1750 278 : gvar->varattno - FirstLowInvalidHeapAttributeNumber);
1751 : }
1752 :
1753 356 : if (bms_is_subset(pkattnos, groupbyattnos))
1754 : {
1755 : /* The PK is a subset of grouping_columns, so we win */
1756 170 : *constraintDeps = lappend_oid(*constraintDeps, constraintOid);
1757 170 : return true;
1758 : }
1759 :
1760 186 : return false;
1761 : }
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