1 /*-------------------------------------------------------------------------
2 *
3 * heap.c
4 * code to create and destroy POSTGRES heap relations
5 *
6 * Portions Copyright (c) 1996-2016, PostgreSQL Global Development Group
7 * Portions Copyright (c) 1994, Regents of the University of California
8 *
9 *
10 * IDENTIFICATION
11 * src/backend/catalog/heap.c
12 *
13 *
14 * INTERFACE ROUTINES
15 * heap_create() - Create an uncataloged heap relation
16 * heap_create_with_catalog() - Create a cataloged relation
17 * heap_drop_with_catalog() - Removes named relation from catalogs
18 *
19 * NOTES
20 * this code taken from access/heap/create.c, which contains
21 * the old heap_create_with_catalog, amcreate, and amdestroy.
22 * those routines will soon call these routines using the function
23 * manager,
24 * just like the poorly named "NewXXX" routines do. The
25 * "New" routines are all going to die soon, once and for all!
26 * -cim 1/13/91
27 *
28 *-------------------------------------------------------------------------
29 */
30 #include "postgres.h"
31
32 #include "access/htup_details.h"
33 #include "access/multixact.h"
34 #include "access/sysattr.h"
35 #include "access/transam.h"
36 #include "access/xact.h"
37 #include "access/xlog.h"
38 #include "catalog/binary_upgrade.h"
39 #include "catalog/catalog.h"
40 #include "catalog/dependency.h"
41 #include "catalog/heap.h"
42 #include "catalog/index.h"
43 #include "catalog/objectaccess.h"
44 #include "catalog/pg_attrdef.h"
45 #include "catalog/pg_collation.h"
46 #include "catalog/pg_constraint.h"
47 #include "catalog/pg_constraint_fn.h"
48 #include "catalog/pg_foreign_table.h"
49 #include "catalog/pg_inherits.h"
50 #include "catalog/pg_namespace.h"
51 #include "catalog/pg_statistic.h"
52 #include "catalog/pg_tablespace.h"
53 #include "catalog/pg_type.h"
54 #include "catalog/pg_type_fn.h"
55 #include "catalog/storage.h"
56 #include "catalog/storage_xlog.h"
57 #include "commands/tablecmds.h"
58 #include "commands/typecmds.h"
59 #include "miscadmin.h"
60 #include "nodes/nodeFuncs.h"
61 #include "optimizer/var.h"
62 #include "parser/parse_coerce.h"
63 #include "parser/parse_collate.h"
64 #include "parser/parse_expr.h"
65 #include "parser/parse_relation.h"
66 #include "storage/predicate.h"
67 #include "storage/smgr.h"
68 #include "utils/acl.h"
69 #include "utils/builtins.h"
70 #include "utils/fmgroids.h"
71 #include "utils/inval.h"
72 #include "utils/lsyscache.h"
73 #include "utils/rel.h"
74 #include "utils/ruleutils.h"
75 #include "utils/snapmgr.h"
76 #include "utils/syscache.h"
77 #include "utils/tqual.h"
78
79
80 /* Potentially set by pg_upgrade_support functions */
81 Oid binary_upgrade_next_heap_pg_class_oid = InvalidOid;
82 Oid binary_upgrade_next_toast_pg_class_oid = InvalidOid;
83
84 static void AddNewRelationTuple(Relation pg_class_desc,
85 Relation new_rel_desc,
86 Oid new_rel_oid,
87 Oid new_type_oid,
88 Oid reloftype,
89 Oid relowner,
90 char relkind,
91 Datum relacl,
92 Datum reloptions);
93 static ObjectAddress AddNewRelationType(const char *typeName,
94 Oid typeNamespace,
95 Oid new_rel_oid,
96 char new_rel_kind,
97 Oid ownerid,
98 Oid new_row_type,
99 Oid new_array_type);
100 static void RelationRemoveInheritance(Oid relid);
101 static Oid StoreRelCheck(Relation rel, char *ccname, Node *expr,
102 bool is_validated, bool is_local, int inhcount,
103 bool is_no_inherit, bool is_internal);
104 static void StoreConstraints(Relation rel, List *cooked_constraints,
105 bool is_internal);
106 static bool MergeWithExistingConstraint(Relation rel, char *ccname, Node *expr,
107 bool allow_merge, bool is_local,
108 bool is_initially_valid,
109 bool is_no_inherit);
110 static void SetRelationNumChecks(Relation rel, int numchecks);
111 static Node *cookConstraint(ParseState *pstate,
112 Node *raw_constraint,
113 char *relname);
114 static List *insert_ordered_unique_oid(List *list, Oid datum);
115
116
117 /* ----------------------------------------------------------------
118 * XXX UGLY HARD CODED BADNESS FOLLOWS XXX
119 *
120 * these should all be moved to someplace in the lib/catalog
121 * module, if not obliterated first.
122 * ----------------------------------------------------------------
123 */
124
125
126 /*
127 * Note:
128 * Should the system special case these attributes in the future?
129 * Advantage: consume much less space in the ATTRIBUTE relation.
130 * Disadvantage: special cases will be all over the place.
131 */
132
133 /*
134 * The initializers below do not include trailing variable length fields,
135 * but that's OK - we're never going to reference anything beyond the
136 * fixed-size portion of the structure anyway.
137 */
138
139 static FormData_pg_attribute a1 = {
140 0, {"ctid"}, TIDOID, 0, sizeof(ItemPointerData),
141 SelfItemPointerAttributeNumber, 0, -1, -1,
142 false, 'p', 's', true, false, false, true, 0
143 };
144
145 static FormData_pg_attribute a2 = {
146 0, {"oid"}, OIDOID, 0, sizeof(Oid),
147 ObjectIdAttributeNumber, 0, -1, -1,
148 true, 'p', 'i', true, false, false, true, 0
149 };
150
151 static FormData_pg_attribute a3 = {
152 0, {"xmin"}, XIDOID, 0, sizeof(TransactionId),
153 MinTransactionIdAttributeNumber, 0, -1, -1,
154 true, 'p', 'i', true, false, false, true, 0
155 };
156
157 static FormData_pg_attribute a4 = {
158 0, {"cmin"}, CIDOID, 0, sizeof(CommandId),
159 MinCommandIdAttributeNumber, 0, -1, -1,
160 true, 'p', 'i', true, false, false, true, 0
161 };
162
163 static FormData_pg_attribute a5 = {
164 0, {"xmax"}, XIDOID, 0, sizeof(TransactionId),
165 MaxTransactionIdAttributeNumber, 0, -1, -1,
166 true, 'p', 'i', true, false, false, true, 0
167 };
168
169 static FormData_pg_attribute a6 = {
170 0, {"cmax"}, CIDOID, 0, sizeof(CommandId),
171 MaxCommandIdAttributeNumber, 0, -1, -1,
172 true, 'p', 'i', true, false, false, true, 0
173 };
174
175 /*
176 * We decided to call this attribute "tableoid" rather than say
177 * "classoid" on the basis that in the future there may be more than one
178 * table of a particular class/type. In any case table is still the word
179 * used in SQL.
180 */
181 static FormData_pg_attribute a7 = {
182 0, {"tableoid"}, OIDOID, 0, sizeof(Oid),
183 TableOidAttributeNumber, 0, -1, -1,
184 true, 'p', 'i', true, false, false, true, 0
185 };
186
187 static const Form_pg_attribute SysAtt[] = {&a1, &a2, &a3, &a4, &a5, &a6, &a7};
188
189 /*
190 * This function returns a Form_pg_attribute pointer for a system attribute.
191 * Note that we elog if the presented attno is invalid, which would only
192 * happen if there's a problem upstream.
193 */
194 Form_pg_attribute
SystemAttributeDefinition(AttrNumber attno,bool relhasoids)195 SystemAttributeDefinition(AttrNumber attno, bool relhasoids)
196 {
197 if (attno >= 0 || attno < -(int) lengthof(SysAtt))
198 elog(ERROR, "invalid system attribute number %d", attno);
199 if (attno == ObjectIdAttributeNumber && !relhasoids)
200 elog(ERROR, "invalid system attribute number %d", attno);
201 return SysAtt[-attno - 1];
202 }
203
204 /*
205 * If the given name is a system attribute name, return a Form_pg_attribute
206 * pointer for a prototype definition. If not, return NULL.
207 */
208 Form_pg_attribute
SystemAttributeByName(const char * attname,bool relhasoids)209 SystemAttributeByName(const char *attname, bool relhasoids)
210 {
211 int j;
212
213 for (j = 0; j < (int) lengthof(SysAtt); j++)
214 {
215 Form_pg_attribute att = SysAtt[j];
216
217 if (relhasoids || att->attnum != ObjectIdAttributeNumber)
218 {
219 if (strcmp(NameStr(att->attname), attname) == 0)
220 return att;
221 }
222 }
223
224 return NULL;
225 }
226
227
228 /* ----------------------------------------------------------------
229 * XXX END OF UGLY HARD CODED BADNESS XXX
230 * ---------------------------------------------------------------- */
231
232
233 /* ----------------------------------------------------------------
234 * heap_create - Create an uncataloged heap relation
235 *
236 * Note API change: the caller must now always provide the OID
237 * to use for the relation. The relfilenode may (and, normally,
238 * should) be left unspecified.
239 *
240 * rel->rd_rel is initialized by RelationBuildLocalRelation,
241 * and is mostly zeroes at return.
242 * ----------------------------------------------------------------
243 */
244 Relation
heap_create(const char * relname,Oid relnamespace,Oid reltablespace,Oid relid,Oid relfilenode,TupleDesc tupDesc,char relkind,char relpersistence,bool shared_relation,bool mapped_relation,bool allow_system_table_mods)245 heap_create(const char *relname,
246 Oid relnamespace,
247 Oid reltablespace,
248 Oid relid,
249 Oid relfilenode,
250 TupleDesc tupDesc,
251 char relkind,
252 char relpersistence,
253 bool shared_relation,
254 bool mapped_relation,
255 bool allow_system_table_mods)
256 {
257 bool create_storage;
258 Relation rel;
259
260 /* The caller must have provided an OID for the relation. */
261 Assert(OidIsValid(relid));
262
263 /*
264 * Don't allow creating relations in pg_catalog directly, even though it
265 * is allowed to move user defined relations there. Semantics with search
266 * paths including pg_catalog are too confusing for now.
267 *
268 * But allow creating indexes on relations in pg_catalog even if
269 * allow_system_table_mods = off, upper layers already guarantee it's on a
270 * user defined relation, not a system one.
271 */
272 if (!allow_system_table_mods &&
273 ((IsSystemNamespace(relnamespace) && relkind != RELKIND_INDEX) ||
274 IsToastNamespace(relnamespace)) &&
275 IsNormalProcessingMode())
276 ereport(ERROR,
277 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
278 errmsg("permission denied to create \"%s.%s\"",
279 get_namespace_name(relnamespace), relname),
280 errdetail("System catalog modifications are currently disallowed.")));
281
282 /*
283 * Decide if we need storage or not, and handle a couple other special
284 * cases for particular relkinds.
285 */
286 switch (relkind)
287 {
288 case RELKIND_VIEW:
289 case RELKIND_COMPOSITE_TYPE:
290 case RELKIND_FOREIGN_TABLE:
291 create_storage = false;
292
293 /*
294 * Force reltablespace to zero if the relation has no physical
295 * storage. This is mainly just for cleanliness' sake.
296 */
297 reltablespace = InvalidOid;
298 break;
299 case RELKIND_SEQUENCE:
300 create_storage = true;
301
302 /*
303 * Force reltablespace to zero for sequences, since we don't
304 * support moving them around into different tablespaces.
305 */
306 reltablespace = InvalidOid;
307 break;
308 default:
309 create_storage = true;
310 break;
311 }
312
313 /*
314 * Unless otherwise requested, the physical ID (relfilenode) is initially
315 * the same as the logical ID (OID). When the caller did specify a
316 * relfilenode, it already exists; do not attempt to create it.
317 */
318 if (OidIsValid(relfilenode))
319 create_storage = false;
320 else
321 relfilenode = relid;
322
323 /*
324 * Never allow a pg_class entry to explicitly specify the database's
325 * default tablespace in reltablespace; force it to zero instead. This
326 * ensures that if the database is cloned with a different default
327 * tablespace, the pg_class entry will still match where CREATE DATABASE
328 * will put the physically copied relation.
329 *
330 * Yes, this is a bit of a hack.
331 */
332 if (reltablespace == MyDatabaseTableSpace)
333 reltablespace = InvalidOid;
334
335 /*
336 * build the relcache entry.
337 */
338 rel = RelationBuildLocalRelation(relname,
339 relnamespace,
340 tupDesc,
341 relid,
342 relfilenode,
343 reltablespace,
344 shared_relation,
345 mapped_relation,
346 relpersistence,
347 relkind);
348
349 /*
350 * Have the storage manager create the relation's disk file, if needed.
351 *
352 * We only create the main fork here, other forks will be created on
353 * demand.
354 */
355 if (create_storage)
356 {
357 RelationOpenSmgr(rel);
358 RelationCreateStorage(rel->rd_node, relpersistence);
359 }
360
361 return rel;
362 }
363
364 /* ----------------------------------------------------------------
365 * heap_create_with_catalog - Create a cataloged relation
366 *
367 * this is done in multiple steps:
368 *
369 * 1) CheckAttributeNamesTypes() is used to make certain the tuple
370 * descriptor contains a valid set of attribute names and types
371 *
372 * 2) pg_class is opened and get_relname_relid()
373 * performs a scan to ensure that no relation with the
374 * same name already exists.
375 *
376 * 3) heap_create() is called to create the new relation on disk.
377 *
378 * 4) TypeCreate() is called to define a new type corresponding
379 * to the new relation.
380 *
381 * 5) AddNewRelationTuple() is called to register the
382 * relation in pg_class.
383 *
384 * 6) AddNewAttributeTuples() is called to register the
385 * new relation's schema in pg_attribute.
386 *
387 * 7) StoreConstraints is called () - vadim 08/22/97
388 *
389 * 8) the relations are closed and the new relation's oid
390 * is returned.
391 *
392 * ----------------------------------------------------------------
393 */
394
395 /* --------------------------------
396 * CheckAttributeNamesTypes
397 *
398 * this is used to make certain the tuple descriptor contains a
399 * valid set of attribute names and datatypes. a problem simply
400 * generates ereport(ERROR) which aborts the current transaction.
401 * --------------------------------
402 */
403 void
CheckAttributeNamesTypes(TupleDesc tupdesc,char relkind,bool allow_system_table_mods)404 CheckAttributeNamesTypes(TupleDesc tupdesc, char relkind,
405 bool allow_system_table_mods)
406 {
407 int i;
408 int j;
409 int natts = tupdesc->natts;
410
411 /* Sanity check on column count */
412 if (natts < 0 || natts > MaxHeapAttributeNumber)
413 ereport(ERROR,
414 (errcode(ERRCODE_TOO_MANY_COLUMNS),
415 errmsg("tables can have at most %d columns",
416 MaxHeapAttributeNumber)));
417
418 /*
419 * first check for collision with system attribute names
420 *
421 * Skip this for a view or type relation, since those don't have system
422 * attributes.
423 */
424 if (relkind != RELKIND_VIEW && relkind != RELKIND_COMPOSITE_TYPE)
425 {
426 for (i = 0; i < natts; i++)
427 {
428 if (SystemAttributeByName(NameStr(tupdesc->attrs[i]->attname),
429 tupdesc->tdhasoid) != NULL)
430 ereport(ERROR,
431 (errcode(ERRCODE_DUPLICATE_COLUMN),
432 errmsg("column name \"%s\" conflicts with a system column name",
433 NameStr(tupdesc->attrs[i]->attname))));
434 }
435 }
436
437 /*
438 * next check for repeated attribute names
439 */
440 for (i = 1; i < natts; i++)
441 {
442 for (j = 0; j < i; j++)
443 {
444 if (strcmp(NameStr(tupdesc->attrs[j]->attname),
445 NameStr(tupdesc->attrs[i]->attname)) == 0)
446 ereport(ERROR,
447 (errcode(ERRCODE_DUPLICATE_COLUMN),
448 errmsg("column name \"%s\" specified more than once",
449 NameStr(tupdesc->attrs[j]->attname))));
450 }
451 }
452
453 /*
454 * next check the attribute types
455 */
456 for (i = 0; i < natts; i++)
457 {
458 CheckAttributeType(NameStr(tupdesc->attrs[i]->attname),
459 tupdesc->attrs[i]->atttypid,
460 tupdesc->attrs[i]->attcollation,
461 NIL, /* assume we're creating a new rowtype */
462 allow_system_table_mods);
463 }
464 }
465
466 /* --------------------------------
467 * CheckAttributeType
468 *
469 * Verify that the proposed datatype of an attribute is legal.
470 * This is needed mainly because there are types (and pseudo-types)
471 * in the catalogs that we do not support as elements of real tuples.
472 * We also check some other properties required of a table column.
473 *
474 * If the attribute is being proposed for addition to an existing table or
475 * composite type, pass a one-element list of the rowtype OID as
476 * containing_rowtypes. When checking a to-be-created rowtype, it's
477 * sufficient to pass NIL, because there could not be any recursive reference
478 * to a not-yet-existing rowtype.
479 * --------------------------------
480 */
481 void
CheckAttributeType(const char * attname,Oid atttypid,Oid attcollation,List * containing_rowtypes,bool allow_system_table_mods)482 CheckAttributeType(const char *attname,
483 Oid atttypid, Oid attcollation,
484 List *containing_rowtypes,
485 bool allow_system_table_mods)
486 {
487 char att_typtype = get_typtype(atttypid);
488 Oid att_typelem;
489
490 if (atttypid == UNKNOWNOID)
491 {
492 /*
493 * Warn user, but don't fail, if column to be created has UNKNOWN type
494 * (usually as a result of a 'retrieve into' - jolly)
495 */
496 ereport(WARNING,
497 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
498 errmsg("column \"%s\" has type \"unknown\"", attname),
499 errdetail("Proceeding with relation creation anyway.")));
500 }
501 else if (att_typtype == TYPTYPE_PSEUDO)
502 {
503 /*
504 * Refuse any attempt to create a pseudo-type column, except for a
505 * special hack for pg_statistic: allow ANYARRAY when modifying system
506 * catalogs (this allows creating pg_statistic and cloning it during
507 * VACUUM FULL)
508 */
509 if (atttypid != ANYARRAYOID || !allow_system_table_mods)
510 ereport(ERROR,
511 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
512 errmsg("column \"%s\" has pseudo-type %s",
513 attname, format_type_be(atttypid))));
514 }
515 else if (att_typtype == TYPTYPE_DOMAIN)
516 {
517 /*
518 * If it's a domain, recurse to check its base type.
519 */
520 CheckAttributeType(attname, getBaseType(atttypid), attcollation,
521 containing_rowtypes,
522 allow_system_table_mods);
523 }
524 else if (att_typtype == TYPTYPE_COMPOSITE)
525 {
526 /*
527 * For a composite type, recurse into its attributes.
528 */
529 Relation relation;
530 TupleDesc tupdesc;
531 int i;
532
533 /*
534 * Check for self-containment. Eventually we might be able to allow
535 * this (just return without complaint, if so) but it's not clear how
536 * many other places would require anti-recursion defenses before it
537 * would be safe to allow tables to contain their own rowtype.
538 */
539 if (list_member_oid(containing_rowtypes, atttypid))
540 ereport(ERROR,
541 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
542 errmsg("composite type %s cannot be made a member of itself",
543 format_type_be(atttypid))));
544
545 containing_rowtypes = lcons_oid(atttypid, containing_rowtypes);
546
547 relation = relation_open(get_typ_typrelid(atttypid), AccessShareLock);
548
549 tupdesc = RelationGetDescr(relation);
550
551 for (i = 0; i < tupdesc->natts; i++)
552 {
553 Form_pg_attribute attr = tupdesc->attrs[i];
554
555 if (attr->attisdropped)
556 continue;
557 CheckAttributeType(NameStr(attr->attname),
558 attr->atttypid, attr->attcollation,
559 containing_rowtypes,
560 allow_system_table_mods);
561 }
562
563 relation_close(relation, AccessShareLock);
564
565 containing_rowtypes = list_delete_first(containing_rowtypes);
566 }
567 else if (att_typtype == TYPTYPE_RANGE)
568 {
569 /*
570 * If it's a range, recurse to check its subtype.
571 */
572 CheckAttributeType(attname, get_range_subtype(atttypid),
573 get_range_collation(atttypid),
574 containing_rowtypes,
575 allow_system_table_mods);
576 }
577 else if (OidIsValid((att_typelem = get_element_type(atttypid))))
578 {
579 /*
580 * Must recurse into array types, too, in case they are composite.
581 */
582 CheckAttributeType(attname, att_typelem, attcollation,
583 containing_rowtypes,
584 allow_system_table_mods);
585 }
586
587 /*
588 * This might not be strictly invalid per SQL standard, but it is pretty
589 * useless, and it cannot be dumped, so we must disallow it.
590 */
591 if (!OidIsValid(attcollation) && type_is_collatable(atttypid))
592 ereport(ERROR,
593 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
594 errmsg("no collation was derived for column \"%s\" with collatable type %s",
595 attname, format_type_be(atttypid)),
596 errhint("Use the COLLATE clause to set the collation explicitly.")));
597 }
598
599 /*
600 * InsertPgAttributeTuple
601 * Construct and insert a new tuple in pg_attribute.
602 *
603 * Caller has already opened and locked pg_attribute. new_attribute is the
604 * attribute to insert (but we ignore attacl and attoptions, which are always
605 * initialized to NULL).
606 *
607 * indstate is the index state for CatalogIndexInsert. It can be passed as
608 * NULL, in which case we'll fetch the necessary info. (Don't do this when
609 * inserting multiple attributes, because it's a tad more expensive.)
610 */
611 void
InsertPgAttributeTuple(Relation pg_attribute_rel,Form_pg_attribute new_attribute,CatalogIndexState indstate)612 InsertPgAttributeTuple(Relation pg_attribute_rel,
613 Form_pg_attribute new_attribute,
614 CatalogIndexState indstate)
615 {
616 Datum values[Natts_pg_attribute];
617 bool nulls[Natts_pg_attribute];
618 HeapTuple tup;
619
620 /* This is a tad tedious, but way cleaner than what we used to do... */
621 memset(values, 0, sizeof(values));
622 memset(nulls, false, sizeof(nulls));
623
624 values[Anum_pg_attribute_attrelid - 1] = ObjectIdGetDatum(new_attribute->attrelid);
625 values[Anum_pg_attribute_attname - 1] = NameGetDatum(&new_attribute->attname);
626 values[Anum_pg_attribute_atttypid - 1] = ObjectIdGetDatum(new_attribute->atttypid);
627 values[Anum_pg_attribute_attstattarget - 1] = Int32GetDatum(new_attribute->attstattarget);
628 values[Anum_pg_attribute_attlen - 1] = Int16GetDatum(new_attribute->attlen);
629 values[Anum_pg_attribute_attnum - 1] = Int16GetDatum(new_attribute->attnum);
630 values[Anum_pg_attribute_attndims - 1] = Int32GetDatum(new_attribute->attndims);
631 values[Anum_pg_attribute_attcacheoff - 1] = Int32GetDatum(new_attribute->attcacheoff);
632 values[Anum_pg_attribute_atttypmod - 1] = Int32GetDatum(new_attribute->atttypmod);
633 values[Anum_pg_attribute_attbyval - 1] = BoolGetDatum(new_attribute->attbyval);
634 values[Anum_pg_attribute_attstorage - 1] = CharGetDatum(new_attribute->attstorage);
635 values[Anum_pg_attribute_attalign - 1] = CharGetDatum(new_attribute->attalign);
636 values[Anum_pg_attribute_attnotnull - 1] = BoolGetDatum(new_attribute->attnotnull);
637 values[Anum_pg_attribute_atthasdef - 1] = BoolGetDatum(new_attribute->atthasdef);
638 values[Anum_pg_attribute_attisdropped - 1] = BoolGetDatum(new_attribute->attisdropped);
639 values[Anum_pg_attribute_attislocal - 1] = BoolGetDatum(new_attribute->attislocal);
640 values[Anum_pg_attribute_attinhcount - 1] = Int32GetDatum(new_attribute->attinhcount);
641 values[Anum_pg_attribute_attcollation - 1] = ObjectIdGetDatum(new_attribute->attcollation);
642
643 /* start out with empty permissions and empty options */
644 nulls[Anum_pg_attribute_attacl - 1] = true;
645 nulls[Anum_pg_attribute_attoptions - 1] = true;
646 nulls[Anum_pg_attribute_attfdwoptions - 1] = true;
647
648 tup = heap_form_tuple(RelationGetDescr(pg_attribute_rel), values, nulls);
649
650 /* finally insert the new tuple, update the indexes, and clean up */
651 simple_heap_insert(pg_attribute_rel, tup);
652
653 if (indstate != NULL)
654 CatalogIndexInsert(indstate, tup);
655 else
656 CatalogUpdateIndexes(pg_attribute_rel, tup);
657
658 heap_freetuple(tup);
659 }
660
661 /* --------------------------------
662 * AddNewAttributeTuples
663 *
664 * this registers the new relation's schema by adding
665 * tuples to pg_attribute.
666 * --------------------------------
667 */
668 static void
AddNewAttributeTuples(Oid new_rel_oid,TupleDesc tupdesc,char relkind,bool oidislocal,int oidinhcount)669 AddNewAttributeTuples(Oid new_rel_oid,
670 TupleDesc tupdesc,
671 char relkind,
672 bool oidislocal,
673 int oidinhcount)
674 {
675 Form_pg_attribute attr;
676 int i;
677 Relation rel;
678 CatalogIndexState indstate;
679 int natts = tupdesc->natts;
680 ObjectAddress myself,
681 referenced;
682
683 /*
684 * open pg_attribute and its indexes.
685 */
686 rel = heap_open(AttributeRelationId, RowExclusiveLock);
687
688 indstate = CatalogOpenIndexes(rel);
689
690 /*
691 * First we add the user attributes. This is also a convenient place to
692 * add dependencies on their datatypes and collations.
693 */
694 for (i = 0; i < natts; i++)
695 {
696 attr = tupdesc->attrs[i];
697 /* Fill in the correct relation OID */
698 attr->attrelid = new_rel_oid;
699 /* Make sure these are OK, too */
700 attr->attstattarget = -1;
701 attr->attcacheoff = -1;
702
703 InsertPgAttributeTuple(rel, attr, indstate);
704
705 /* Add dependency info */
706 myself.classId = RelationRelationId;
707 myself.objectId = new_rel_oid;
708 myself.objectSubId = i + 1;
709 referenced.classId = TypeRelationId;
710 referenced.objectId = attr->atttypid;
711 referenced.objectSubId = 0;
712 recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
713
714 /* The default collation is pinned, so don't bother recording it */
715 if (OidIsValid(attr->attcollation) &&
716 attr->attcollation != DEFAULT_COLLATION_OID)
717 {
718 referenced.classId = CollationRelationId;
719 referenced.objectId = attr->attcollation;
720 referenced.objectSubId = 0;
721 recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
722 }
723 }
724
725 /*
726 * Next we add the system attributes. Skip OID if rel has no OIDs. Skip
727 * all for a view or type relation. We don't bother with making datatype
728 * dependencies here, since presumably all these types are pinned.
729 */
730 if (relkind != RELKIND_VIEW && relkind != RELKIND_COMPOSITE_TYPE)
731 {
732 for (i = 0; i < (int) lengthof(SysAtt); i++)
733 {
734 FormData_pg_attribute attStruct;
735
736 /* skip OID where appropriate */
737 if (!tupdesc->tdhasoid &&
738 SysAtt[i]->attnum == ObjectIdAttributeNumber)
739 continue;
740
741 memcpy(&attStruct, (char *) SysAtt[i], sizeof(FormData_pg_attribute));
742
743 /* Fill in the correct relation OID in the copied tuple */
744 attStruct.attrelid = new_rel_oid;
745
746 /* Fill in correct inheritance info for the OID column */
747 if (attStruct.attnum == ObjectIdAttributeNumber)
748 {
749 attStruct.attislocal = oidislocal;
750 attStruct.attinhcount = oidinhcount;
751 }
752
753 InsertPgAttributeTuple(rel, &attStruct, indstate);
754 }
755 }
756
757 /*
758 * clean up
759 */
760 CatalogCloseIndexes(indstate);
761
762 heap_close(rel, RowExclusiveLock);
763 }
764
765 /* --------------------------------
766 * InsertPgClassTuple
767 *
768 * Construct and insert a new tuple in pg_class.
769 *
770 * Caller has already opened and locked pg_class.
771 * Tuple data is taken from new_rel_desc->rd_rel, except for the
772 * variable-width fields which are not present in a cached reldesc.
773 * relacl and reloptions are passed in Datum form (to avoid having
774 * to reference the data types in heap.h). Pass (Datum) 0 to set them
775 * to NULL.
776 * --------------------------------
777 */
778 void
InsertPgClassTuple(Relation pg_class_desc,Relation new_rel_desc,Oid new_rel_oid,Datum relacl,Datum reloptions)779 InsertPgClassTuple(Relation pg_class_desc,
780 Relation new_rel_desc,
781 Oid new_rel_oid,
782 Datum relacl,
783 Datum reloptions)
784 {
785 Form_pg_class rd_rel = new_rel_desc->rd_rel;
786 Datum values[Natts_pg_class];
787 bool nulls[Natts_pg_class];
788 HeapTuple tup;
789
790 /* This is a tad tedious, but way cleaner than what we used to do... */
791 memset(values, 0, sizeof(values));
792 memset(nulls, false, sizeof(nulls));
793
794 values[Anum_pg_class_relname - 1] = NameGetDatum(&rd_rel->relname);
795 values[Anum_pg_class_relnamespace - 1] = ObjectIdGetDatum(rd_rel->relnamespace);
796 values[Anum_pg_class_reltype - 1] = ObjectIdGetDatum(rd_rel->reltype);
797 values[Anum_pg_class_reloftype - 1] = ObjectIdGetDatum(rd_rel->reloftype);
798 values[Anum_pg_class_relowner - 1] = ObjectIdGetDatum(rd_rel->relowner);
799 values[Anum_pg_class_relam - 1] = ObjectIdGetDatum(rd_rel->relam);
800 values[Anum_pg_class_relfilenode - 1] = ObjectIdGetDatum(rd_rel->relfilenode);
801 values[Anum_pg_class_reltablespace - 1] = ObjectIdGetDatum(rd_rel->reltablespace);
802 values[Anum_pg_class_relpages - 1] = Int32GetDatum(rd_rel->relpages);
803 values[Anum_pg_class_reltuples - 1] = Float4GetDatum(rd_rel->reltuples);
804 values[Anum_pg_class_relallvisible - 1] = Int32GetDatum(rd_rel->relallvisible);
805 values[Anum_pg_class_reltoastrelid - 1] = ObjectIdGetDatum(rd_rel->reltoastrelid);
806 values[Anum_pg_class_relhasindex - 1] = BoolGetDatum(rd_rel->relhasindex);
807 values[Anum_pg_class_relisshared - 1] = BoolGetDatum(rd_rel->relisshared);
808 values[Anum_pg_class_relpersistence - 1] = CharGetDatum(rd_rel->relpersistence);
809 values[Anum_pg_class_relkind - 1] = CharGetDatum(rd_rel->relkind);
810 values[Anum_pg_class_relnatts - 1] = Int16GetDatum(rd_rel->relnatts);
811 values[Anum_pg_class_relchecks - 1] = Int16GetDatum(rd_rel->relchecks);
812 values[Anum_pg_class_relhasoids - 1] = BoolGetDatum(rd_rel->relhasoids);
813 values[Anum_pg_class_relhaspkey - 1] = BoolGetDatum(rd_rel->relhaspkey);
814 values[Anum_pg_class_relhasrules - 1] = BoolGetDatum(rd_rel->relhasrules);
815 values[Anum_pg_class_relhastriggers - 1] = BoolGetDatum(rd_rel->relhastriggers);
816 values[Anum_pg_class_relrowsecurity - 1] = BoolGetDatum(rd_rel->relrowsecurity);
817 values[Anum_pg_class_relforcerowsecurity - 1] = BoolGetDatum(rd_rel->relforcerowsecurity);
818 values[Anum_pg_class_relhassubclass - 1] = BoolGetDatum(rd_rel->relhassubclass);
819 values[Anum_pg_class_relispopulated - 1] = BoolGetDatum(rd_rel->relispopulated);
820 values[Anum_pg_class_relreplident - 1] = CharGetDatum(rd_rel->relreplident);
821 values[Anum_pg_class_relfrozenxid - 1] = TransactionIdGetDatum(rd_rel->relfrozenxid);
822 values[Anum_pg_class_relminmxid - 1] = MultiXactIdGetDatum(rd_rel->relminmxid);
823 if (relacl != (Datum) 0)
824 values[Anum_pg_class_relacl - 1] = relacl;
825 else
826 nulls[Anum_pg_class_relacl - 1] = true;
827 if (reloptions != (Datum) 0)
828 values[Anum_pg_class_reloptions - 1] = reloptions;
829 else
830 nulls[Anum_pg_class_reloptions - 1] = true;
831
832 tup = heap_form_tuple(RelationGetDescr(pg_class_desc), values, nulls);
833
834 /*
835 * The new tuple must have the oid already chosen for the rel. Sure would
836 * be embarrassing to do this sort of thing in polite company.
837 */
838 HeapTupleSetOid(tup, new_rel_oid);
839
840 /* finally insert the new tuple, update the indexes, and clean up */
841 simple_heap_insert(pg_class_desc, tup);
842
843 CatalogUpdateIndexes(pg_class_desc, tup);
844
845 heap_freetuple(tup);
846 }
847
848 /* --------------------------------
849 * AddNewRelationTuple
850 *
851 * this registers the new relation in the catalogs by
852 * adding a tuple to pg_class.
853 * --------------------------------
854 */
855 static void
AddNewRelationTuple(Relation pg_class_desc,Relation new_rel_desc,Oid new_rel_oid,Oid new_type_oid,Oid reloftype,Oid relowner,char relkind,Datum relacl,Datum reloptions)856 AddNewRelationTuple(Relation pg_class_desc,
857 Relation new_rel_desc,
858 Oid new_rel_oid,
859 Oid new_type_oid,
860 Oid reloftype,
861 Oid relowner,
862 char relkind,
863 Datum relacl,
864 Datum reloptions)
865 {
866 Form_pg_class new_rel_reltup;
867
868 /*
869 * first we update some of the information in our uncataloged relation's
870 * relation descriptor.
871 */
872 new_rel_reltup = new_rel_desc->rd_rel;
873
874 switch (relkind)
875 {
876 case RELKIND_RELATION:
877 case RELKIND_MATVIEW:
878 case RELKIND_INDEX:
879 case RELKIND_TOASTVALUE:
880 /* The relation is real, but as yet empty */
881 new_rel_reltup->relpages = 0;
882 new_rel_reltup->reltuples = 0;
883 new_rel_reltup->relallvisible = 0;
884 break;
885 case RELKIND_SEQUENCE:
886 /* Sequences always have a known size */
887 new_rel_reltup->relpages = 1;
888 new_rel_reltup->reltuples = 1;
889 new_rel_reltup->relallvisible = 0;
890 break;
891 default:
892 /* Views, etc, have no disk storage */
893 new_rel_reltup->relpages = 0;
894 new_rel_reltup->reltuples = 0;
895 new_rel_reltup->relallvisible = 0;
896 break;
897 }
898
899 /* Initialize relfrozenxid and relminmxid */
900 if (relkind == RELKIND_RELATION ||
901 relkind == RELKIND_MATVIEW ||
902 relkind == RELKIND_TOASTVALUE)
903 {
904 /*
905 * Initialize to the minimum XID that could put tuples in the table.
906 * We know that no xacts older than RecentXmin are still running, so
907 * that will do.
908 */
909 new_rel_reltup->relfrozenxid = RecentXmin;
910
911 /*
912 * Similarly, initialize the minimum Multixact to the first value that
913 * could possibly be stored in tuples in the table. Running
914 * transactions could reuse values from their local cache, so we are
915 * careful to consider all currently running multis.
916 *
917 * XXX this could be refined further, but is it worth the hassle?
918 */
919 new_rel_reltup->relminmxid = GetOldestMultiXactId();
920 }
921 else
922 {
923 /*
924 * Other relation types will not contain XIDs, so set relfrozenxid to
925 * InvalidTransactionId. (Note: a sequence does contain a tuple, but
926 * we force its xmin to be FrozenTransactionId always; see
927 * commands/sequence.c.)
928 */
929 new_rel_reltup->relfrozenxid = InvalidTransactionId;
930 new_rel_reltup->relminmxid = InvalidMultiXactId;
931 }
932
933 new_rel_reltup->relowner = relowner;
934 new_rel_reltup->reltype = new_type_oid;
935 new_rel_reltup->reloftype = reloftype;
936
937 new_rel_desc->rd_att->tdtypeid = new_type_oid;
938
939 /* Now build and insert the tuple */
940 InsertPgClassTuple(pg_class_desc, new_rel_desc, new_rel_oid,
941 relacl, reloptions);
942 }
943
944
945 /* --------------------------------
946 * AddNewRelationType -
947 *
948 * define a composite type corresponding to the new relation
949 * --------------------------------
950 */
951 static ObjectAddress
AddNewRelationType(const char * typeName,Oid typeNamespace,Oid new_rel_oid,char new_rel_kind,Oid ownerid,Oid new_row_type,Oid new_array_type)952 AddNewRelationType(const char *typeName,
953 Oid typeNamespace,
954 Oid new_rel_oid,
955 char new_rel_kind,
956 Oid ownerid,
957 Oid new_row_type,
958 Oid new_array_type)
959 {
960 return
961 TypeCreate(new_row_type, /* optional predetermined OID */
962 typeName, /* type name */
963 typeNamespace, /* type namespace */
964 new_rel_oid, /* relation oid */
965 new_rel_kind, /* relation kind */
966 ownerid, /* owner's ID */
967 -1, /* internal size (varlena) */
968 TYPTYPE_COMPOSITE, /* type-type (composite) */
969 TYPCATEGORY_COMPOSITE, /* type-category (ditto) */
970 false, /* composite types are never preferred */
971 DEFAULT_TYPDELIM, /* default array delimiter */
972 F_RECORD_IN, /* input procedure */
973 F_RECORD_OUT, /* output procedure */
974 F_RECORD_RECV, /* receive procedure */
975 F_RECORD_SEND, /* send procedure */
976 InvalidOid, /* typmodin procedure - none */
977 InvalidOid, /* typmodout procedure - none */
978 InvalidOid, /* analyze procedure - default */
979 InvalidOid, /* array element type - irrelevant */
980 false, /* this is not an array type */
981 new_array_type, /* array type if any */
982 InvalidOid, /* domain base type - irrelevant */
983 NULL, /* default value - none */
984 NULL, /* default binary representation */
985 false, /* passed by reference */
986 'd', /* alignment - must be the largest! */
987 'x', /* fully TOASTable */
988 -1, /* typmod */
989 0, /* array dimensions for typBaseType */
990 false, /* Type NOT NULL */
991 InvalidOid); /* rowtypes never have a collation */
992 }
993
994 /* --------------------------------
995 * heap_create_with_catalog
996 *
997 * creates a new cataloged relation. see comments above.
998 *
999 * Arguments:
1000 * relname: name to give to new rel
1001 * relnamespace: OID of namespace it goes in
1002 * reltablespace: OID of tablespace it goes in
1003 * relid: OID to assign to new rel, or InvalidOid to select a new OID
1004 * reltypeid: OID to assign to rel's rowtype, or InvalidOid to select one
1005 * reloftypeid: if a typed table, OID of underlying type; else InvalidOid
1006 * ownerid: OID of new rel's owner
1007 * tupdesc: tuple descriptor (source of column definitions)
1008 * cooked_constraints: list of precooked check constraints and defaults
1009 * relkind: relkind for new rel
1010 * relpersistence: rel's persistence status (permanent, temp, or unlogged)
1011 * shared_relation: TRUE if it's to be a shared relation
1012 * mapped_relation: TRUE if the relation will use the relfilenode map
1013 * oidislocal: TRUE if oid column (if any) should be marked attislocal
1014 * oidinhcount: attinhcount to assign to oid column (if any)
1015 * oncommit: ON COMMIT marking (only relevant if it's a temp table)
1016 * reloptions: reloptions in Datum form, or (Datum) 0 if none
1017 * use_user_acl: TRUE if should look for user-defined default permissions;
1018 * if FALSE, relacl is always set NULL
1019 * allow_system_table_mods: TRUE to allow creation in system namespaces
1020 * is_internal: is this a system-generated catalog?
1021 *
1022 * Output parameters:
1023 * typaddress: if not null, gets the object address of the new pg_type entry
1024 *
1025 * Returns the OID of the new relation
1026 * --------------------------------
1027 */
1028 Oid
heap_create_with_catalog(const char * relname,Oid relnamespace,Oid reltablespace,Oid relid,Oid reltypeid,Oid reloftypeid,Oid ownerid,TupleDesc tupdesc,List * cooked_constraints,char relkind,char relpersistence,bool shared_relation,bool mapped_relation,bool oidislocal,int oidinhcount,OnCommitAction oncommit,Datum reloptions,bool use_user_acl,bool allow_system_table_mods,bool is_internal,ObjectAddress * typaddress)1029 heap_create_with_catalog(const char *relname,
1030 Oid relnamespace,
1031 Oid reltablespace,
1032 Oid relid,
1033 Oid reltypeid,
1034 Oid reloftypeid,
1035 Oid ownerid,
1036 TupleDesc tupdesc,
1037 List *cooked_constraints,
1038 char relkind,
1039 char relpersistence,
1040 bool shared_relation,
1041 bool mapped_relation,
1042 bool oidislocal,
1043 int oidinhcount,
1044 OnCommitAction oncommit,
1045 Datum reloptions,
1046 bool use_user_acl,
1047 bool allow_system_table_mods,
1048 bool is_internal,
1049 ObjectAddress *typaddress)
1050 {
1051 Relation pg_class_desc;
1052 Relation new_rel_desc;
1053 Acl *relacl;
1054 Oid existing_relid;
1055 Oid old_type_oid;
1056 Oid new_type_oid;
1057 ObjectAddress new_type_addr;
1058 Oid new_array_oid = InvalidOid;
1059
1060 pg_class_desc = heap_open(RelationRelationId, RowExclusiveLock);
1061
1062 /*
1063 * sanity checks
1064 */
1065 Assert(IsNormalProcessingMode() || IsBootstrapProcessingMode());
1066
1067 CheckAttributeNamesTypes(tupdesc, relkind, allow_system_table_mods);
1068
1069 /*
1070 * This would fail later on anyway, if the relation already exists. But
1071 * by catching it here we can emit a nicer error message.
1072 */
1073 existing_relid = get_relname_relid(relname, relnamespace);
1074 if (existing_relid != InvalidOid)
1075 ereport(ERROR,
1076 (errcode(ERRCODE_DUPLICATE_TABLE),
1077 errmsg("relation \"%s\" already exists", relname)));
1078
1079 /*
1080 * Since we are going to create a rowtype as well, also check for
1081 * collision with an existing type name. If there is one and it's an
1082 * autogenerated array, we can rename it out of the way; otherwise we can
1083 * at least give a good error message.
1084 */
1085 old_type_oid = GetSysCacheOid2(TYPENAMENSP,
1086 CStringGetDatum(relname),
1087 ObjectIdGetDatum(relnamespace));
1088 if (OidIsValid(old_type_oid))
1089 {
1090 if (!moveArrayTypeName(old_type_oid, relname, relnamespace))
1091 ereport(ERROR,
1092 (errcode(ERRCODE_DUPLICATE_OBJECT),
1093 errmsg("type \"%s\" already exists", relname),
1094 errhint("A relation has an associated type of the same name, "
1095 "so you must use a name that doesn't conflict "
1096 "with any existing type.")));
1097 }
1098
1099 /*
1100 * Shared relations must be in pg_global (last-ditch check)
1101 */
1102 if (shared_relation && reltablespace != GLOBALTABLESPACE_OID)
1103 elog(ERROR, "shared relations must be placed in pg_global tablespace");
1104
1105 /*
1106 * Allocate an OID for the relation, unless we were told what to use.
1107 *
1108 * The OID will be the relfilenode as well, so make sure it doesn't
1109 * collide with either pg_class OIDs or existing physical files.
1110 */
1111 if (!OidIsValid(relid))
1112 {
1113 /* Use binary-upgrade override for pg_class.oid/relfilenode? */
1114 if (IsBinaryUpgrade &&
1115 (relkind == RELKIND_RELATION || relkind == RELKIND_SEQUENCE ||
1116 relkind == RELKIND_VIEW || relkind == RELKIND_MATVIEW ||
1117 relkind == RELKIND_COMPOSITE_TYPE || relkind == RELKIND_FOREIGN_TABLE))
1118 {
1119 if (!OidIsValid(binary_upgrade_next_heap_pg_class_oid))
1120 ereport(ERROR,
1121 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
1122 errmsg("pg_class heap OID value not set when in binary upgrade mode")));
1123
1124 relid = binary_upgrade_next_heap_pg_class_oid;
1125 binary_upgrade_next_heap_pg_class_oid = InvalidOid;
1126 }
1127 /* There might be no TOAST table, so we have to test for it. */
1128 else if (IsBinaryUpgrade &&
1129 OidIsValid(binary_upgrade_next_toast_pg_class_oid) &&
1130 relkind == RELKIND_TOASTVALUE)
1131 {
1132 relid = binary_upgrade_next_toast_pg_class_oid;
1133 binary_upgrade_next_toast_pg_class_oid = InvalidOid;
1134 }
1135 else
1136 relid = GetNewRelFileNode(reltablespace, pg_class_desc,
1137 relpersistence);
1138 }
1139
1140 /*
1141 * Determine the relation's initial permissions.
1142 */
1143 if (use_user_acl)
1144 {
1145 switch (relkind)
1146 {
1147 case RELKIND_RELATION:
1148 case RELKIND_VIEW:
1149 case RELKIND_MATVIEW:
1150 case RELKIND_FOREIGN_TABLE:
1151 relacl = get_user_default_acl(ACL_OBJECT_RELATION, ownerid,
1152 relnamespace);
1153 break;
1154 case RELKIND_SEQUENCE:
1155 relacl = get_user_default_acl(ACL_OBJECT_SEQUENCE, ownerid,
1156 relnamespace);
1157 break;
1158 default:
1159 relacl = NULL;
1160 break;
1161 }
1162 }
1163 else
1164 relacl = NULL;
1165
1166 /*
1167 * Create the relcache entry (mostly dummy at this point) and the physical
1168 * disk file. (If we fail further down, it's the smgr's responsibility to
1169 * remove the disk file again.)
1170 */
1171 new_rel_desc = heap_create(relname,
1172 relnamespace,
1173 reltablespace,
1174 relid,
1175 InvalidOid,
1176 tupdesc,
1177 relkind,
1178 relpersistence,
1179 shared_relation,
1180 mapped_relation,
1181 allow_system_table_mods);
1182
1183 Assert(relid == RelationGetRelid(new_rel_desc));
1184
1185 /*
1186 * Decide whether to create an array type over the relation's rowtype. We
1187 * do not create any array types for system catalogs (ie, those made
1188 * during initdb). We do not create them where the use of a relation as
1189 * such is an implementation detail: toast tables, sequences and indexes.
1190 */
1191 if (IsUnderPostmaster && (relkind == RELKIND_RELATION ||
1192 relkind == RELKIND_VIEW ||
1193 relkind == RELKIND_MATVIEW ||
1194 relkind == RELKIND_FOREIGN_TABLE ||
1195 relkind == RELKIND_COMPOSITE_TYPE))
1196 new_array_oid = AssignTypeArrayOid();
1197
1198 /*
1199 * Since defining a relation also defines a complex type, we add a new
1200 * system type corresponding to the new relation. The OID of the type can
1201 * be preselected by the caller, but if reltypeid is InvalidOid, we'll
1202 * generate a new OID for it.
1203 *
1204 * NOTE: we could get a unique-index failure here, in case someone else is
1205 * creating the same type name in parallel but hadn't committed yet when
1206 * we checked for a duplicate name above.
1207 */
1208 new_type_addr = AddNewRelationType(relname,
1209 relnamespace,
1210 relid,
1211 relkind,
1212 ownerid,
1213 reltypeid,
1214 new_array_oid);
1215 new_type_oid = new_type_addr.objectId;
1216 if (typaddress)
1217 *typaddress = new_type_addr;
1218
1219 /*
1220 * Now make the array type if wanted.
1221 */
1222 if (OidIsValid(new_array_oid))
1223 {
1224 char *relarrayname;
1225
1226 relarrayname = makeArrayTypeName(relname, relnamespace);
1227
1228 TypeCreate(new_array_oid, /* force the type's OID to this */
1229 relarrayname, /* Array type name */
1230 relnamespace, /* Same namespace as parent */
1231 InvalidOid, /* Not composite, no relationOid */
1232 0, /* relkind, also N/A here */
1233 ownerid, /* owner's ID */
1234 -1, /* Internal size (varlena) */
1235 TYPTYPE_BASE, /* Not composite - typelem is */
1236 TYPCATEGORY_ARRAY, /* type-category (array) */
1237 false, /* array types are never preferred */
1238 DEFAULT_TYPDELIM, /* default array delimiter */
1239 F_ARRAY_IN, /* array input proc */
1240 F_ARRAY_OUT, /* array output proc */
1241 F_ARRAY_RECV, /* array recv (bin) proc */
1242 F_ARRAY_SEND, /* array send (bin) proc */
1243 InvalidOid, /* typmodin procedure - none */
1244 InvalidOid, /* typmodout procedure - none */
1245 F_ARRAY_TYPANALYZE, /* array analyze procedure */
1246 new_type_oid, /* array element type - the rowtype */
1247 true, /* yes, this is an array type */
1248 InvalidOid, /* this has no array type */
1249 InvalidOid, /* domain base type - irrelevant */
1250 NULL, /* default value - none */
1251 NULL, /* default binary representation */
1252 false, /* passed by reference */
1253 'd', /* alignment - must be the largest! */
1254 'x', /* fully TOASTable */
1255 -1, /* typmod */
1256 0, /* array dimensions for typBaseType */
1257 false, /* Type NOT NULL */
1258 InvalidOid); /* rowtypes never have a collation */
1259
1260 pfree(relarrayname);
1261 }
1262
1263 /*
1264 * now create an entry in pg_class for the relation.
1265 *
1266 * NOTE: we could get a unique-index failure here, in case someone else is
1267 * creating the same relation name in parallel but hadn't committed yet
1268 * when we checked for a duplicate name above.
1269 */
1270 AddNewRelationTuple(pg_class_desc,
1271 new_rel_desc,
1272 relid,
1273 new_type_oid,
1274 reloftypeid,
1275 ownerid,
1276 relkind,
1277 PointerGetDatum(relacl),
1278 reloptions);
1279
1280 /*
1281 * now add tuples to pg_attribute for the attributes in our new relation.
1282 */
1283 AddNewAttributeTuples(relid, new_rel_desc->rd_att, relkind,
1284 oidislocal, oidinhcount);
1285
1286 /*
1287 * Make a dependency link to force the relation to be deleted if its
1288 * namespace is. Also make a dependency link to its owner, as well as
1289 * dependencies for any roles mentioned in the default ACL.
1290 *
1291 * For composite types, these dependencies are tracked for the pg_type
1292 * entry, so we needn't record them here. Likewise, TOAST tables don't
1293 * need a namespace dependency (they live in a pinned namespace) nor an
1294 * owner dependency (they depend indirectly through the parent table), nor
1295 * should they have any ACL entries. The same applies for extension
1296 * dependencies.
1297 *
1298 * If it's a temp table, we do not make it an extension member; this
1299 * prevents the unintuitive result that deletion of the temp table at
1300 * session end would make the whole extension go away.
1301 *
1302 * Also, skip this in bootstrap mode, since we don't make dependencies
1303 * while bootstrapping.
1304 */
1305 if (relkind != RELKIND_COMPOSITE_TYPE &&
1306 relkind != RELKIND_TOASTVALUE &&
1307 !IsBootstrapProcessingMode())
1308 {
1309 ObjectAddress myself,
1310 referenced;
1311
1312 myself.classId = RelationRelationId;
1313 myself.objectId = relid;
1314 myself.objectSubId = 0;
1315
1316 referenced.classId = NamespaceRelationId;
1317 referenced.objectId = relnamespace;
1318 referenced.objectSubId = 0;
1319 recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
1320
1321 recordDependencyOnOwner(RelationRelationId, relid, ownerid);
1322
1323 recordDependencyOnNewAcl(RelationRelationId, relid, 0, ownerid, relacl);
1324
1325 if (relpersistence != RELPERSISTENCE_TEMP)
1326 recordDependencyOnCurrentExtension(&myself, false);
1327
1328 if (reloftypeid)
1329 {
1330 referenced.classId = TypeRelationId;
1331 referenced.objectId = reloftypeid;
1332 referenced.objectSubId = 0;
1333 recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
1334 }
1335 }
1336
1337 /* Post creation hook for new relation */
1338 InvokeObjectPostCreateHookArg(RelationRelationId, relid, 0, is_internal);
1339
1340 /*
1341 * Store any supplied constraints and defaults.
1342 *
1343 * NB: this may do a CommandCounterIncrement and rebuild the relcache
1344 * entry, so the relation must be valid and self-consistent at this point.
1345 * In particular, there are not yet constraints and defaults anywhere.
1346 */
1347 StoreConstraints(new_rel_desc, cooked_constraints, is_internal);
1348
1349 /*
1350 * If there's a special on-commit action, remember it
1351 */
1352 if (oncommit != ONCOMMIT_NOOP)
1353 register_on_commit_action(relid, oncommit);
1354
1355 if (relpersistence == RELPERSISTENCE_UNLOGGED)
1356 {
1357 Assert(relkind == RELKIND_RELATION || relkind == RELKIND_MATVIEW ||
1358 relkind == RELKIND_TOASTVALUE);
1359 heap_create_init_fork(new_rel_desc);
1360 }
1361
1362 /*
1363 * ok, the relation has been cataloged, so close our relations and return
1364 * the OID of the newly created relation.
1365 */
1366 heap_close(new_rel_desc, NoLock); /* do not unlock till end of xact */
1367 heap_close(pg_class_desc, RowExclusiveLock);
1368
1369 return relid;
1370 }
1371
1372 /*
1373 * Set up an init fork for an unlogged table so that it can be correctly
1374 * reinitialized on restart. An immediate sync is required even if the
1375 * page has been logged, because the write did not go through
1376 * shared_buffers and therefore a concurrent checkpoint may have moved
1377 * the redo pointer past our xlog record. Recovery may as well remove it
1378 * while replaying, for example, XLOG_DBASE_CREATE or XLOG_TBLSPC_CREATE
1379 * record. Therefore, logging is necessary even if wal_level=minimal.
1380 */
1381 void
heap_create_init_fork(Relation rel)1382 heap_create_init_fork(Relation rel)
1383 {
1384 RelationOpenSmgr(rel);
1385 smgrcreate(rel->rd_smgr, INIT_FORKNUM, false);
1386 log_smgrcreate(&rel->rd_smgr->smgr_rnode.node, INIT_FORKNUM);
1387 smgrimmedsync(rel->rd_smgr, INIT_FORKNUM);
1388 }
1389
1390 /*
1391 * RelationRemoveInheritance
1392 *
1393 * Formerly, this routine checked for child relations and aborted the
1394 * deletion if any were found. Now we rely on the dependency mechanism
1395 * to check for or delete child relations. By the time we get here,
1396 * there are no children and we need only remove any pg_inherits rows
1397 * linking this relation to its parent(s).
1398 */
1399 static void
RelationRemoveInheritance(Oid relid)1400 RelationRemoveInheritance(Oid relid)
1401 {
1402 Relation catalogRelation;
1403 SysScanDesc scan;
1404 ScanKeyData key;
1405 HeapTuple tuple;
1406
1407 catalogRelation = heap_open(InheritsRelationId, RowExclusiveLock);
1408
1409 ScanKeyInit(&key,
1410 Anum_pg_inherits_inhrelid,
1411 BTEqualStrategyNumber, F_OIDEQ,
1412 ObjectIdGetDatum(relid));
1413
1414 scan = systable_beginscan(catalogRelation, InheritsRelidSeqnoIndexId, true,
1415 NULL, 1, &key);
1416
1417 while (HeapTupleIsValid(tuple = systable_getnext(scan)))
1418 simple_heap_delete(catalogRelation, &tuple->t_self);
1419
1420 systable_endscan(scan);
1421 heap_close(catalogRelation, RowExclusiveLock);
1422 }
1423
1424 /*
1425 * DeleteRelationTuple
1426 *
1427 * Remove pg_class row for the given relid.
1428 *
1429 * Note: this is shared by relation deletion and index deletion. It's
1430 * not intended for use anyplace else.
1431 */
1432 void
DeleteRelationTuple(Oid relid)1433 DeleteRelationTuple(Oid relid)
1434 {
1435 Relation pg_class_desc;
1436 HeapTuple tup;
1437
1438 /* Grab an appropriate lock on the pg_class relation */
1439 pg_class_desc = heap_open(RelationRelationId, RowExclusiveLock);
1440
1441 tup = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
1442 if (!HeapTupleIsValid(tup))
1443 elog(ERROR, "cache lookup failed for relation %u", relid);
1444
1445 /* delete the relation tuple from pg_class, and finish up */
1446 simple_heap_delete(pg_class_desc, &tup->t_self);
1447
1448 ReleaseSysCache(tup);
1449
1450 heap_close(pg_class_desc, RowExclusiveLock);
1451 }
1452
1453 /*
1454 * DeleteAttributeTuples
1455 *
1456 * Remove pg_attribute rows for the given relid.
1457 *
1458 * Note: this is shared by relation deletion and index deletion. It's
1459 * not intended for use anyplace else.
1460 */
1461 void
DeleteAttributeTuples(Oid relid)1462 DeleteAttributeTuples(Oid relid)
1463 {
1464 Relation attrel;
1465 SysScanDesc scan;
1466 ScanKeyData key[1];
1467 HeapTuple atttup;
1468
1469 /* Grab an appropriate lock on the pg_attribute relation */
1470 attrel = heap_open(AttributeRelationId, RowExclusiveLock);
1471
1472 /* Use the index to scan only attributes of the target relation */
1473 ScanKeyInit(&key[0],
1474 Anum_pg_attribute_attrelid,
1475 BTEqualStrategyNumber, F_OIDEQ,
1476 ObjectIdGetDatum(relid));
1477
1478 scan = systable_beginscan(attrel, AttributeRelidNumIndexId, true,
1479 NULL, 1, key);
1480
1481 /* Delete all the matching tuples */
1482 while ((atttup = systable_getnext(scan)) != NULL)
1483 simple_heap_delete(attrel, &atttup->t_self);
1484
1485 /* Clean up after the scan */
1486 systable_endscan(scan);
1487 heap_close(attrel, RowExclusiveLock);
1488 }
1489
1490 /*
1491 * DeleteSystemAttributeTuples
1492 *
1493 * Remove pg_attribute rows for system columns of the given relid.
1494 *
1495 * Note: this is only used when converting a table to a view. Views don't
1496 * have system columns, so we should remove them from pg_attribute.
1497 */
1498 void
DeleteSystemAttributeTuples(Oid relid)1499 DeleteSystemAttributeTuples(Oid relid)
1500 {
1501 Relation attrel;
1502 SysScanDesc scan;
1503 ScanKeyData key[2];
1504 HeapTuple atttup;
1505
1506 /* Grab an appropriate lock on the pg_attribute relation */
1507 attrel = heap_open(AttributeRelationId, RowExclusiveLock);
1508
1509 /* Use the index to scan only system attributes of the target relation */
1510 ScanKeyInit(&key[0],
1511 Anum_pg_attribute_attrelid,
1512 BTEqualStrategyNumber, F_OIDEQ,
1513 ObjectIdGetDatum(relid));
1514 ScanKeyInit(&key[1],
1515 Anum_pg_attribute_attnum,
1516 BTLessEqualStrategyNumber, F_INT2LE,
1517 Int16GetDatum(0));
1518
1519 scan = systable_beginscan(attrel, AttributeRelidNumIndexId, true,
1520 NULL, 2, key);
1521
1522 /* Delete all the matching tuples */
1523 while ((atttup = systable_getnext(scan)) != NULL)
1524 simple_heap_delete(attrel, &atttup->t_self);
1525
1526 /* Clean up after the scan */
1527 systable_endscan(scan);
1528 heap_close(attrel, RowExclusiveLock);
1529 }
1530
1531 /*
1532 * RemoveAttributeById
1533 *
1534 * This is the guts of ALTER TABLE DROP COLUMN: actually mark the attribute
1535 * deleted in pg_attribute. We also remove pg_statistic entries for it.
1536 * (Everything else needed, such as getting rid of any pg_attrdef entry,
1537 * is handled by dependency.c.)
1538 */
1539 void
RemoveAttributeById(Oid relid,AttrNumber attnum)1540 RemoveAttributeById(Oid relid, AttrNumber attnum)
1541 {
1542 Relation rel;
1543 Relation attr_rel;
1544 HeapTuple tuple;
1545 Form_pg_attribute attStruct;
1546 char newattname[NAMEDATALEN];
1547
1548 /*
1549 * Grab an exclusive lock on the target table, which we will NOT release
1550 * until end of transaction. (In the simple case where we are directly
1551 * dropping this column, AlterTableDropColumn already did this ... but
1552 * when cascading from a drop of some other object, we may not have any
1553 * lock.)
1554 */
1555 rel = relation_open(relid, AccessExclusiveLock);
1556
1557 attr_rel = heap_open(AttributeRelationId, RowExclusiveLock);
1558
1559 tuple = SearchSysCacheCopy2(ATTNUM,
1560 ObjectIdGetDatum(relid),
1561 Int16GetDatum(attnum));
1562 if (!HeapTupleIsValid(tuple)) /* shouldn't happen */
1563 elog(ERROR, "cache lookup failed for attribute %d of relation %u",
1564 attnum, relid);
1565 attStruct = (Form_pg_attribute) GETSTRUCT(tuple);
1566
1567 if (attnum < 0)
1568 {
1569 /* System attribute (probably OID) ... just delete the row */
1570
1571 simple_heap_delete(attr_rel, &tuple->t_self);
1572 }
1573 else
1574 {
1575 /* Dropping user attributes is lots harder */
1576
1577 /* Mark the attribute as dropped */
1578 attStruct->attisdropped = true;
1579
1580 /*
1581 * Set the type OID to invalid. A dropped attribute's type link
1582 * cannot be relied on (once the attribute is dropped, the type might
1583 * be too). Fortunately we do not need the type row --- the only
1584 * really essential information is the type's typlen and typalign,
1585 * which are preserved in the attribute's attlen and attalign. We set
1586 * atttypid to zero here as a means of catching code that incorrectly
1587 * expects it to be valid.
1588 */
1589 attStruct->atttypid = InvalidOid;
1590
1591 /* Remove any NOT NULL constraint the column may have */
1592 attStruct->attnotnull = false;
1593
1594 /* We don't want to keep stats for it anymore */
1595 attStruct->attstattarget = 0;
1596
1597 /*
1598 * Change the column name to something that isn't likely to conflict
1599 */
1600 snprintf(newattname, sizeof(newattname),
1601 "........pg.dropped.%d........", attnum);
1602 namestrcpy(&(attStruct->attname), newattname);
1603
1604 simple_heap_update(attr_rel, &tuple->t_self, tuple);
1605
1606 /* keep the system catalog indexes current */
1607 CatalogUpdateIndexes(attr_rel, tuple);
1608 }
1609
1610 /*
1611 * Because updating the pg_attribute row will trigger a relcache flush for
1612 * the target relation, we need not do anything else to notify other
1613 * backends of the change.
1614 */
1615
1616 heap_close(attr_rel, RowExclusiveLock);
1617
1618 if (attnum > 0)
1619 RemoveStatistics(relid, attnum);
1620
1621 relation_close(rel, NoLock);
1622 }
1623
1624 /*
1625 * RemoveAttrDefault
1626 *
1627 * If the specified relation/attribute has a default, remove it.
1628 * (If no default, raise error if complain is true, else return quietly.)
1629 */
1630 void
RemoveAttrDefault(Oid relid,AttrNumber attnum,DropBehavior behavior,bool complain,bool internal)1631 RemoveAttrDefault(Oid relid, AttrNumber attnum,
1632 DropBehavior behavior, bool complain, bool internal)
1633 {
1634 Relation attrdef_rel;
1635 ScanKeyData scankeys[2];
1636 SysScanDesc scan;
1637 HeapTuple tuple;
1638 bool found = false;
1639
1640 attrdef_rel = heap_open(AttrDefaultRelationId, RowExclusiveLock);
1641
1642 ScanKeyInit(&scankeys[0],
1643 Anum_pg_attrdef_adrelid,
1644 BTEqualStrategyNumber, F_OIDEQ,
1645 ObjectIdGetDatum(relid));
1646 ScanKeyInit(&scankeys[1],
1647 Anum_pg_attrdef_adnum,
1648 BTEqualStrategyNumber, F_INT2EQ,
1649 Int16GetDatum(attnum));
1650
1651 scan = systable_beginscan(attrdef_rel, AttrDefaultIndexId, true,
1652 NULL, 2, scankeys);
1653
1654 /* There should be at most one matching tuple, but we loop anyway */
1655 while (HeapTupleIsValid(tuple = systable_getnext(scan)))
1656 {
1657 ObjectAddress object;
1658
1659 object.classId = AttrDefaultRelationId;
1660 object.objectId = HeapTupleGetOid(tuple);
1661 object.objectSubId = 0;
1662
1663 performDeletion(&object, behavior,
1664 internal ? PERFORM_DELETION_INTERNAL : 0);
1665
1666 found = true;
1667 }
1668
1669 systable_endscan(scan);
1670 heap_close(attrdef_rel, RowExclusiveLock);
1671
1672 if (complain && !found)
1673 elog(ERROR, "could not find attrdef tuple for relation %u attnum %d",
1674 relid, attnum);
1675 }
1676
1677 /*
1678 * RemoveAttrDefaultById
1679 *
1680 * Remove a pg_attrdef entry specified by OID. This is the guts of
1681 * attribute-default removal. Note it should be called via performDeletion,
1682 * not directly.
1683 */
1684 void
RemoveAttrDefaultById(Oid attrdefId)1685 RemoveAttrDefaultById(Oid attrdefId)
1686 {
1687 Relation attrdef_rel;
1688 Relation attr_rel;
1689 Relation myrel;
1690 ScanKeyData scankeys[1];
1691 SysScanDesc scan;
1692 HeapTuple tuple;
1693 Oid myrelid;
1694 AttrNumber myattnum;
1695
1696 /* Grab an appropriate lock on the pg_attrdef relation */
1697 attrdef_rel = heap_open(AttrDefaultRelationId, RowExclusiveLock);
1698
1699 /* Find the pg_attrdef tuple */
1700 ScanKeyInit(&scankeys[0],
1701 ObjectIdAttributeNumber,
1702 BTEqualStrategyNumber, F_OIDEQ,
1703 ObjectIdGetDatum(attrdefId));
1704
1705 scan = systable_beginscan(attrdef_rel, AttrDefaultOidIndexId, true,
1706 NULL, 1, scankeys);
1707
1708 tuple = systable_getnext(scan);
1709 if (!HeapTupleIsValid(tuple))
1710 elog(ERROR, "could not find tuple for attrdef %u", attrdefId);
1711
1712 myrelid = ((Form_pg_attrdef) GETSTRUCT(tuple))->adrelid;
1713 myattnum = ((Form_pg_attrdef) GETSTRUCT(tuple))->adnum;
1714
1715 /* Get an exclusive lock on the relation owning the attribute */
1716 myrel = relation_open(myrelid, AccessExclusiveLock);
1717
1718 /* Now we can delete the pg_attrdef row */
1719 simple_heap_delete(attrdef_rel, &tuple->t_self);
1720
1721 systable_endscan(scan);
1722 heap_close(attrdef_rel, RowExclusiveLock);
1723
1724 /* Fix the pg_attribute row */
1725 attr_rel = heap_open(AttributeRelationId, RowExclusiveLock);
1726
1727 tuple = SearchSysCacheCopy2(ATTNUM,
1728 ObjectIdGetDatum(myrelid),
1729 Int16GetDatum(myattnum));
1730 if (!HeapTupleIsValid(tuple)) /* shouldn't happen */
1731 elog(ERROR, "cache lookup failed for attribute %d of relation %u",
1732 myattnum, myrelid);
1733
1734 ((Form_pg_attribute) GETSTRUCT(tuple))->atthasdef = false;
1735
1736 simple_heap_update(attr_rel, &tuple->t_self, tuple);
1737
1738 /* keep the system catalog indexes current */
1739 CatalogUpdateIndexes(attr_rel, tuple);
1740
1741 /*
1742 * Our update of the pg_attribute row will force a relcache rebuild, so
1743 * there's nothing else to do here.
1744 */
1745 heap_close(attr_rel, RowExclusiveLock);
1746
1747 /* Keep lock on attribute's rel until end of xact */
1748 relation_close(myrel, NoLock);
1749 }
1750
1751 /*
1752 * heap_drop_with_catalog - removes specified relation from catalogs
1753 *
1754 * Note that this routine is not responsible for dropping objects that are
1755 * linked to the pg_class entry via dependencies (for example, indexes and
1756 * constraints). Those are deleted by the dependency-tracing logic in
1757 * dependency.c before control gets here. In general, therefore, this routine
1758 * should never be called directly; go through performDeletion() instead.
1759 */
1760 void
heap_drop_with_catalog(Oid relid)1761 heap_drop_with_catalog(Oid relid)
1762 {
1763 Relation rel;
1764
1765 /*
1766 * Open and lock the relation.
1767 */
1768 rel = relation_open(relid, AccessExclusiveLock);
1769
1770 /*
1771 * There can no longer be anyone *else* touching the relation, but we
1772 * might still have open queries or cursors, or pending trigger events, in
1773 * our own session.
1774 */
1775 CheckTableNotInUse(rel, "DROP TABLE");
1776
1777 /*
1778 * This effectively deletes all rows in the table, and may be done in a
1779 * serializable transaction. In that case we must record a rw-conflict in
1780 * to this transaction from each transaction holding a predicate lock on
1781 * the table.
1782 */
1783 CheckTableForSerializableConflictIn(rel);
1784
1785 /*
1786 * Delete pg_foreign_table tuple first.
1787 */
1788 if (rel->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
1789 {
1790 Relation rel;
1791 HeapTuple tuple;
1792
1793 rel = heap_open(ForeignTableRelationId, RowExclusiveLock);
1794
1795 tuple = SearchSysCache1(FOREIGNTABLEREL, ObjectIdGetDatum(relid));
1796 if (!HeapTupleIsValid(tuple))
1797 elog(ERROR, "cache lookup failed for foreign table %u", relid);
1798
1799 simple_heap_delete(rel, &tuple->t_self);
1800
1801 ReleaseSysCache(tuple);
1802 heap_close(rel, RowExclusiveLock);
1803 }
1804
1805 /*
1806 * Schedule unlinking of the relation's physical files at commit.
1807 */
1808 if (rel->rd_rel->relkind != RELKIND_VIEW &&
1809 rel->rd_rel->relkind != RELKIND_COMPOSITE_TYPE &&
1810 rel->rd_rel->relkind != RELKIND_FOREIGN_TABLE)
1811 {
1812 RelationDropStorage(rel);
1813 }
1814
1815 /*
1816 * Close relcache entry, but *keep* AccessExclusiveLock on the relation
1817 * until transaction commit. This ensures no one else will try to do
1818 * something with the doomed relation.
1819 */
1820 relation_close(rel, NoLock);
1821
1822 /*
1823 * Forget any ON COMMIT action for the rel
1824 */
1825 remove_on_commit_action(relid);
1826
1827 /*
1828 * Flush the relation from the relcache. We want to do this before
1829 * starting to remove catalog entries, just to be certain that no relcache
1830 * entry rebuild will happen partway through. (That should not really
1831 * matter, since we don't do CommandCounterIncrement here, but let's be
1832 * safe.)
1833 */
1834 RelationForgetRelation(relid);
1835
1836 /*
1837 * remove inheritance information
1838 */
1839 RelationRemoveInheritance(relid);
1840
1841 /*
1842 * delete statistics
1843 */
1844 RemoveStatistics(relid, 0);
1845
1846 /*
1847 * delete attribute tuples
1848 */
1849 DeleteAttributeTuples(relid);
1850
1851 /*
1852 * delete relation tuple
1853 */
1854 DeleteRelationTuple(relid);
1855 }
1856
1857
1858 /*
1859 * Store a default expression for column attnum of relation rel.
1860 *
1861 * Returns the OID of the new pg_attrdef tuple.
1862 */
1863 Oid
StoreAttrDefault(Relation rel,AttrNumber attnum,Node * expr,bool is_internal)1864 StoreAttrDefault(Relation rel, AttrNumber attnum,
1865 Node *expr, bool is_internal)
1866 {
1867 char *adbin;
1868 char *adsrc;
1869 Relation adrel;
1870 HeapTuple tuple;
1871 Datum values[4];
1872 static bool nulls[4] = {false, false, false, false};
1873 Relation attrrel;
1874 HeapTuple atttup;
1875 Form_pg_attribute attStruct;
1876 Oid attrdefOid;
1877 ObjectAddress colobject,
1878 defobject;
1879
1880 /*
1881 * Flatten expression to string form for storage.
1882 */
1883 adbin = nodeToString(expr);
1884
1885 /*
1886 * Also deparse it to form the mostly-obsolete adsrc field.
1887 */
1888 adsrc = deparse_expression(expr,
1889 deparse_context_for(RelationGetRelationName(rel),
1890 RelationGetRelid(rel)),
1891 false, false);
1892
1893 /*
1894 * Make the pg_attrdef entry.
1895 */
1896 values[Anum_pg_attrdef_adrelid - 1] = RelationGetRelid(rel);
1897 values[Anum_pg_attrdef_adnum - 1] = attnum;
1898 values[Anum_pg_attrdef_adbin - 1] = CStringGetTextDatum(adbin);
1899 values[Anum_pg_attrdef_adsrc - 1] = CStringGetTextDatum(adsrc);
1900
1901 adrel = heap_open(AttrDefaultRelationId, RowExclusiveLock);
1902
1903 tuple = heap_form_tuple(adrel->rd_att, values, nulls);
1904 attrdefOid = simple_heap_insert(adrel, tuple);
1905
1906 CatalogUpdateIndexes(adrel, tuple);
1907
1908 defobject.classId = AttrDefaultRelationId;
1909 defobject.objectId = attrdefOid;
1910 defobject.objectSubId = 0;
1911
1912 heap_close(adrel, RowExclusiveLock);
1913
1914 /* now can free some of the stuff allocated above */
1915 pfree(DatumGetPointer(values[Anum_pg_attrdef_adbin - 1]));
1916 pfree(DatumGetPointer(values[Anum_pg_attrdef_adsrc - 1]));
1917 heap_freetuple(tuple);
1918 pfree(adbin);
1919 pfree(adsrc);
1920
1921 /*
1922 * Update the pg_attribute entry for the column to show that a default
1923 * exists.
1924 */
1925 attrrel = heap_open(AttributeRelationId, RowExclusiveLock);
1926 atttup = SearchSysCacheCopy2(ATTNUM,
1927 ObjectIdGetDatum(RelationGetRelid(rel)),
1928 Int16GetDatum(attnum));
1929 if (!HeapTupleIsValid(atttup))
1930 elog(ERROR, "cache lookup failed for attribute %d of relation %u",
1931 attnum, RelationGetRelid(rel));
1932 attStruct = (Form_pg_attribute) GETSTRUCT(atttup);
1933 if (!attStruct->atthasdef)
1934 {
1935 attStruct->atthasdef = true;
1936 simple_heap_update(attrrel, &atttup->t_self, atttup);
1937 /* keep catalog indexes current */
1938 CatalogUpdateIndexes(attrrel, atttup);
1939 }
1940 heap_close(attrrel, RowExclusiveLock);
1941 heap_freetuple(atttup);
1942
1943 /*
1944 * Make a dependency so that the pg_attrdef entry goes away if the column
1945 * (or whole table) is deleted.
1946 */
1947 colobject.classId = RelationRelationId;
1948 colobject.objectId = RelationGetRelid(rel);
1949 colobject.objectSubId = attnum;
1950
1951 recordDependencyOn(&defobject, &colobject, DEPENDENCY_AUTO);
1952
1953 /*
1954 * Record dependencies on objects used in the expression, too.
1955 */
1956 recordDependencyOnExpr(&defobject, expr, NIL, DEPENDENCY_NORMAL);
1957
1958 /*
1959 * Post creation hook for attribute defaults.
1960 *
1961 * XXX. ALTER TABLE ALTER COLUMN SET/DROP DEFAULT is implemented with a
1962 * couple of deletion/creation of the attribute's default entry, so the
1963 * callee should check existence of an older version of this entry if it
1964 * needs to distinguish.
1965 */
1966 InvokeObjectPostCreateHookArg(AttrDefaultRelationId,
1967 RelationGetRelid(rel), attnum, is_internal);
1968
1969 return attrdefOid;
1970 }
1971
1972 /*
1973 * Store a check-constraint expression for the given relation.
1974 *
1975 * Caller is responsible for updating the count of constraints
1976 * in the pg_class entry for the relation.
1977 *
1978 * The OID of the new constraint is returned.
1979 */
1980 static Oid
StoreRelCheck(Relation rel,char * ccname,Node * expr,bool is_validated,bool is_local,int inhcount,bool is_no_inherit,bool is_internal)1981 StoreRelCheck(Relation rel, char *ccname, Node *expr,
1982 bool is_validated, bool is_local, int inhcount,
1983 bool is_no_inherit, bool is_internal)
1984 {
1985 char *ccbin;
1986 char *ccsrc;
1987 List *varList;
1988 int keycount;
1989 int16 *attNos;
1990 Oid constrOid;
1991
1992 /*
1993 * Flatten expression to string form for storage.
1994 */
1995 ccbin = nodeToString(expr);
1996
1997 /*
1998 * Also deparse it to form the mostly-obsolete consrc field.
1999 */
2000 ccsrc = deparse_expression(expr,
2001 deparse_context_for(RelationGetRelationName(rel),
2002 RelationGetRelid(rel)),
2003 false, false);
2004
2005 /*
2006 * Find columns of rel that are used in expr
2007 *
2008 * NB: pull_var_clause is okay here only because we don't allow subselects
2009 * in check constraints; it would fail to examine the contents of
2010 * subselects.
2011 */
2012 varList = pull_var_clause(expr, 0);
2013 keycount = list_length(varList);
2014
2015 if (keycount > 0)
2016 {
2017 ListCell *vl;
2018 int i = 0;
2019
2020 attNos = (int16 *) palloc(keycount * sizeof(int16));
2021 foreach(vl, varList)
2022 {
2023 Var *var = (Var *) lfirst(vl);
2024 int j;
2025
2026 for (j = 0; j < i; j++)
2027 if (attNos[j] == var->varattno)
2028 break;
2029 if (j == i)
2030 attNos[i++] = var->varattno;
2031 }
2032 keycount = i;
2033 }
2034 else
2035 attNos = NULL;
2036
2037 /*
2038 * Create the Check Constraint
2039 */
2040 constrOid =
2041 CreateConstraintEntry(ccname, /* Constraint Name */
2042 RelationGetNamespace(rel), /* namespace */
2043 CONSTRAINT_CHECK, /* Constraint Type */
2044 false, /* Is Deferrable */
2045 false, /* Is Deferred */
2046 is_validated,
2047 RelationGetRelid(rel), /* relation */
2048 attNos, /* attrs in the constraint */
2049 keycount, /* # attrs in the constraint */
2050 InvalidOid, /* not a domain constraint */
2051 InvalidOid, /* no associated index */
2052 InvalidOid, /* Foreign key fields */
2053 NULL,
2054 NULL,
2055 NULL,
2056 NULL,
2057 0,
2058 ' ',
2059 ' ',
2060 ' ',
2061 NULL, /* not an exclusion constraint */
2062 expr, /* Tree form of check constraint */
2063 ccbin, /* Binary form of check constraint */
2064 ccsrc, /* Source form of check constraint */
2065 is_local, /* conislocal */
2066 inhcount, /* coninhcount */
2067 is_no_inherit, /* connoinherit */
2068 is_internal); /* internally constructed? */
2069
2070 pfree(ccbin);
2071 pfree(ccsrc);
2072
2073 return constrOid;
2074 }
2075
2076 /*
2077 * Store defaults and constraints (passed as a list of CookedConstraint).
2078 *
2079 * Each CookedConstraint struct is modified to store the new catalog tuple OID.
2080 *
2081 * NOTE: only pre-cooked expressions will be passed this way, which is to
2082 * say expressions inherited from an existing relation. Newly parsed
2083 * expressions can be added later, by direct calls to StoreAttrDefault
2084 * and StoreRelCheck (see AddRelationNewConstraints()).
2085 */
2086 static void
StoreConstraints(Relation rel,List * cooked_constraints,bool is_internal)2087 StoreConstraints(Relation rel, List *cooked_constraints, bool is_internal)
2088 {
2089 int numchecks = 0;
2090 ListCell *lc;
2091
2092 if (cooked_constraints == NIL)
2093 return; /* nothing to do */
2094
2095 /*
2096 * Deparsing of constraint expressions will fail unless the just-created
2097 * pg_attribute tuples for this relation are made visible. So, bump the
2098 * command counter. CAUTION: this will cause a relcache entry rebuild.
2099 */
2100 CommandCounterIncrement();
2101
2102 foreach(lc, cooked_constraints)
2103 {
2104 CookedConstraint *con = (CookedConstraint *) lfirst(lc);
2105
2106 switch (con->contype)
2107 {
2108 case CONSTR_DEFAULT:
2109 con->conoid = StoreAttrDefault(rel, con->attnum, con->expr,
2110 is_internal);
2111 break;
2112 case CONSTR_CHECK:
2113 con->conoid =
2114 StoreRelCheck(rel, con->name, con->expr,
2115 !con->skip_validation, con->is_local,
2116 con->inhcount, con->is_no_inherit,
2117 is_internal);
2118 numchecks++;
2119 break;
2120 default:
2121 elog(ERROR, "unrecognized constraint type: %d",
2122 (int) con->contype);
2123 }
2124 }
2125
2126 if (numchecks > 0)
2127 SetRelationNumChecks(rel, numchecks);
2128 }
2129
2130 /*
2131 * AddRelationNewConstraints
2132 *
2133 * Add new column default expressions and/or constraint check expressions
2134 * to an existing relation. This is defined to do both for efficiency in
2135 * DefineRelation, but of course you can do just one or the other by passing
2136 * empty lists.
2137 *
2138 * rel: relation to be modified
2139 * newColDefaults: list of RawColumnDefault structures
2140 * newConstraints: list of Constraint nodes
2141 * allow_merge: TRUE if check constraints may be merged with existing ones
2142 * is_local: TRUE if definition is local, FALSE if it's inherited
2143 * is_internal: TRUE if result of some internal process, not a user request
2144 *
2145 * All entries in newColDefaults will be processed. Entries in newConstraints
2146 * will be processed only if they are CONSTR_CHECK type.
2147 *
2148 * Returns a list of CookedConstraint nodes that shows the cooked form of
2149 * the default and constraint expressions added to the relation.
2150 *
2151 * NB: caller should have opened rel with AccessExclusiveLock, and should
2152 * hold that lock till end of transaction. Also, we assume the caller has
2153 * done a CommandCounterIncrement if necessary to make the relation's catalog
2154 * tuples visible.
2155 */
2156 List *
AddRelationNewConstraints(Relation rel,List * newColDefaults,List * newConstraints,bool allow_merge,bool is_local,bool is_internal)2157 AddRelationNewConstraints(Relation rel,
2158 List *newColDefaults,
2159 List *newConstraints,
2160 bool allow_merge,
2161 bool is_local,
2162 bool is_internal)
2163 {
2164 List *cookedConstraints = NIL;
2165 TupleDesc tupleDesc;
2166 TupleConstr *oldconstr;
2167 int numoldchecks;
2168 ParseState *pstate;
2169 RangeTblEntry *rte;
2170 int numchecks;
2171 List *checknames;
2172 ListCell *cell;
2173 Node *expr;
2174 CookedConstraint *cooked;
2175
2176 /*
2177 * Get info about existing constraints.
2178 */
2179 tupleDesc = RelationGetDescr(rel);
2180 oldconstr = tupleDesc->constr;
2181 if (oldconstr)
2182 numoldchecks = oldconstr->num_check;
2183 else
2184 numoldchecks = 0;
2185
2186 /*
2187 * Create a dummy ParseState and insert the target relation as its sole
2188 * rangetable entry. We need a ParseState for transformExpr.
2189 */
2190 pstate = make_parsestate(NULL);
2191 rte = addRangeTableEntryForRelation(pstate,
2192 rel,
2193 NULL,
2194 false,
2195 true);
2196 addRTEtoQuery(pstate, rte, true, true, true);
2197
2198 /*
2199 * Process column default expressions.
2200 */
2201 foreach(cell, newColDefaults)
2202 {
2203 RawColumnDefault *colDef = (RawColumnDefault *) lfirst(cell);
2204 Form_pg_attribute atp = rel->rd_att->attrs[colDef->attnum - 1];
2205 Oid defOid;
2206
2207 expr = cookDefault(pstate, colDef->raw_default,
2208 atp->atttypid, atp->atttypmod,
2209 NameStr(atp->attname));
2210
2211 /*
2212 * If the expression is just a NULL constant, we do not bother to make
2213 * an explicit pg_attrdef entry, since the default behavior is
2214 * equivalent.
2215 *
2216 * Note a nonobvious property of this test: if the column is of a
2217 * domain type, what we'll get is not a bare null Const but a
2218 * CoerceToDomain expr, so we will not discard the default. This is
2219 * critical because the column default needs to be retained to
2220 * override any default that the domain might have.
2221 */
2222 if (expr == NULL ||
2223 (IsA(expr, Const) &&((Const *) expr)->constisnull))
2224 continue;
2225
2226 defOid = StoreAttrDefault(rel, colDef->attnum, expr, is_internal);
2227
2228 cooked = (CookedConstraint *) palloc(sizeof(CookedConstraint));
2229 cooked->contype = CONSTR_DEFAULT;
2230 cooked->conoid = defOid;
2231 cooked->name = NULL;
2232 cooked->attnum = colDef->attnum;
2233 cooked->expr = expr;
2234 cooked->skip_validation = false;
2235 cooked->is_local = is_local;
2236 cooked->inhcount = is_local ? 0 : 1;
2237 cooked->is_no_inherit = false;
2238 cookedConstraints = lappend(cookedConstraints, cooked);
2239 }
2240
2241 /*
2242 * Process constraint expressions.
2243 */
2244 numchecks = numoldchecks;
2245 checknames = NIL;
2246 foreach(cell, newConstraints)
2247 {
2248 Constraint *cdef = (Constraint *) lfirst(cell);
2249 char *ccname;
2250 Oid constrOid;
2251
2252 if (cdef->contype != CONSTR_CHECK)
2253 continue;
2254
2255 if (cdef->raw_expr != NULL)
2256 {
2257 Assert(cdef->cooked_expr == NULL);
2258
2259 /*
2260 * Transform raw parsetree to executable expression, and verify
2261 * it's valid as a CHECK constraint.
2262 */
2263 expr = cookConstraint(pstate, cdef->raw_expr,
2264 RelationGetRelationName(rel));
2265 }
2266 else
2267 {
2268 Assert(cdef->cooked_expr != NULL);
2269
2270 /*
2271 * Here, we assume the parser will only pass us valid CHECK
2272 * expressions, so we do no particular checking.
2273 */
2274 expr = stringToNode(cdef->cooked_expr);
2275 }
2276
2277 /*
2278 * Check name uniqueness, or generate a name if none was given.
2279 */
2280 if (cdef->conname != NULL)
2281 {
2282 ListCell *cell2;
2283
2284 ccname = cdef->conname;
2285 /* Check against other new constraints */
2286 /* Needed because we don't do CommandCounterIncrement in loop */
2287 foreach(cell2, checknames)
2288 {
2289 if (strcmp((char *) lfirst(cell2), ccname) == 0)
2290 ereport(ERROR,
2291 (errcode(ERRCODE_DUPLICATE_OBJECT),
2292 errmsg("check constraint \"%s\" already exists",
2293 ccname)));
2294 }
2295
2296 /* save name for future checks */
2297 checknames = lappend(checknames, ccname);
2298
2299 /*
2300 * Check against pre-existing constraints. If we are allowed to
2301 * merge with an existing constraint, there's no more to do here.
2302 * (We omit the duplicate constraint from the result, which is
2303 * what ATAddCheckConstraint wants.)
2304 */
2305 if (MergeWithExistingConstraint(rel, ccname, expr,
2306 allow_merge, is_local,
2307 cdef->initially_valid,
2308 cdef->is_no_inherit))
2309 continue;
2310 }
2311 else
2312 {
2313 /*
2314 * When generating a name, we want to create "tab_col_check" for a
2315 * column constraint and "tab_check" for a table constraint. We
2316 * no longer have any info about the syntactic positioning of the
2317 * constraint phrase, so we approximate this by seeing whether the
2318 * expression references more than one column. (If the user
2319 * played by the rules, the result is the same...)
2320 *
2321 * Note: pull_var_clause() doesn't descend into sublinks, but we
2322 * eliminated those above; and anyway this only needs to be an
2323 * approximate answer.
2324 */
2325 List *vars;
2326 char *colname;
2327
2328 vars = pull_var_clause(expr, 0);
2329
2330 /* eliminate duplicates */
2331 vars = list_union(NIL, vars);
2332
2333 if (list_length(vars) == 1)
2334 colname = get_attname(RelationGetRelid(rel),
2335 ((Var *) linitial(vars))->varattno);
2336 else
2337 colname = NULL;
2338
2339 ccname = ChooseConstraintName(RelationGetRelationName(rel),
2340 colname,
2341 "check",
2342 RelationGetNamespace(rel),
2343 checknames);
2344
2345 /* save name for future checks */
2346 checknames = lappend(checknames, ccname);
2347 }
2348
2349 /*
2350 * OK, store it.
2351 */
2352 constrOid =
2353 StoreRelCheck(rel, ccname, expr, cdef->initially_valid, is_local,
2354 is_local ? 0 : 1, cdef->is_no_inherit, is_internal);
2355
2356 numchecks++;
2357
2358 cooked = (CookedConstraint *) palloc(sizeof(CookedConstraint));
2359 cooked->contype = CONSTR_CHECK;
2360 cooked->conoid = constrOid;
2361 cooked->name = ccname;
2362 cooked->attnum = 0;
2363 cooked->expr = expr;
2364 cooked->skip_validation = cdef->skip_validation;
2365 cooked->is_local = is_local;
2366 cooked->inhcount = is_local ? 0 : 1;
2367 cooked->is_no_inherit = cdef->is_no_inherit;
2368 cookedConstraints = lappend(cookedConstraints, cooked);
2369 }
2370
2371 /*
2372 * Update the count of constraints in the relation's pg_class tuple. We do
2373 * this even if there was no change, in order to ensure that an SI update
2374 * message is sent out for the pg_class tuple, which will force other
2375 * backends to rebuild their relcache entries for the rel. (This is
2376 * critical if we added defaults but not constraints.)
2377 */
2378 SetRelationNumChecks(rel, numchecks);
2379
2380 return cookedConstraints;
2381 }
2382
2383 /*
2384 * Check for a pre-existing check constraint that conflicts with a proposed
2385 * new one, and either adjust its conislocal/coninhcount settings or throw
2386 * error as needed.
2387 *
2388 * Returns TRUE if merged (constraint is a duplicate), or FALSE if it's
2389 * got a so-far-unique name, or throws error if conflict.
2390 *
2391 * XXX See MergeConstraintsIntoExisting too if you change this code.
2392 */
2393 static bool
MergeWithExistingConstraint(Relation rel,char * ccname,Node * expr,bool allow_merge,bool is_local,bool is_initially_valid,bool is_no_inherit)2394 MergeWithExistingConstraint(Relation rel, char *ccname, Node *expr,
2395 bool allow_merge, bool is_local,
2396 bool is_initially_valid,
2397 bool is_no_inherit)
2398 {
2399 bool found;
2400 Relation conDesc;
2401 SysScanDesc conscan;
2402 ScanKeyData skey[2];
2403 HeapTuple tup;
2404
2405 /* Search for a pg_constraint entry with same name and relation */
2406 conDesc = heap_open(ConstraintRelationId, RowExclusiveLock);
2407
2408 found = false;
2409
2410 ScanKeyInit(&skey[0],
2411 Anum_pg_constraint_conname,
2412 BTEqualStrategyNumber, F_NAMEEQ,
2413 CStringGetDatum(ccname));
2414
2415 ScanKeyInit(&skey[1],
2416 Anum_pg_constraint_connamespace,
2417 BTEqualStrategyNumber, F_OIDEQ,
2418 ObjectIdGetDatum(RelationGetNamespace(rel)));
2419
2420 conscan = systable_beginscan(conDesc, ConstraintNameNspIndexId, true,
2421 NULL, 2, skey);
2422
2423 while (HeapTupleIsValid(tup = systable_getnext(conscan)))
2424 {
2425 Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(tup);
2426
2427 if (con->conrelid == RelationGetRelid(rel))
2428 {
2429 /* Found it. Conflicts if not identical check constraint */
2430 if (con->contype == CONSTRAINT_CHECK)
2431 {
2432 Datum val;
2433 bool isnull;
2434
2435 val = fastgetattr(tup,
2436 Anum_pg_constraint_conbin,
2437 conDesc->rd_att, &isnull);
2438 if (isnull)
2439 elog(ERROR, "null conbin for rel %s",
2440 RelationGetRelationName(rel));
2441 if (equal(expr, stringToNode(TextDatumGetCString(val))))
2442 found = true;
2443 }
2444
2445 /*
2446 * If the existing constraint is purely inherited (no local
2447 * definition) then interpret addition of a local constraint as a
2448 * legal merge. This allows ALTER ADD CONSTRAINT on parent and
2449 * child tables to be given in either order with same end state.
2450 */
2451 if (is_local && !con->conislocal)
2452 allow_merge = true;
2453
2454 if (!found || !allow_merge)
2455 ereport(ERROR,
2456 (errcode(ERRCODE_DUPLICATE_OBJECT),
2457 errmsg("constraint \"%s\" for relation \"%s\" already exists",
2458 ccname, RelationGetRelationName(rel))));
2459
2460 /* If the child constraint is "no inherit" then cannot merge */
2461 if (con->connoinherit)
2462 ereport(ERROR,
2463 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
2464 errmsg("constraint \"%s\" conflicts with non-inherited constraint on relation \"%s\"",
2465 ccname, RelationGetRelationName(rel))));
2466
2467 /*
2468 * Must not change an existing inherited constraint to "no
2469 * inherit" status. That's because inherited constraints should
2470 * be able to propagate to lower-level children.
2471 */
2472 if (con->coninhcount > 0 && is_no_inherit)
2473 ereport(ERROR,
2474 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
2475 errmsg("constraint \"%s\" conflicts with inherited constraint on relation \"%s\"",
2476 ccname, RelationGetRelationName(rel))));
2477
2478 /*
2479 * If the child constraint is "not valid" then cannot merge with a
2480 * valid parent constraint
2481 */
2482 if (is_initially_valid && !con->convalidated)
2483 ereport(ERROR,
2484 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
2485 errmsg("constraint \"%s\" conflicts with NOT VALID constraint on relation \"%s\"",
2486 ccname, RelationGetRelationName(rel))));
2487
2488 /* OK to update the tuple */
2489 ereport(NOTICE,
2490 (errmsg("merging constraint \"%s\" with inherited definition",
2491 ccname)));
2492
2493 tup = heap_copytuple(tup);
2494 con = (Form_pg_constraint) GETSTRUCT(tup);
2495
2496 if (is_local)
2497 con->conislocal = true;
2498 else
2499 con->coninhcount++;
2500 if (is_no_inherit)
2501 {
2502 Assert(is_local);
2503 con->connoinherit = true;
2504 }
2505 simple_heap_update(conDesc, &tup->t_self, tup);
2506 CatalogUpdateIndexes(conDesc, tup);
2507 break;
2508 }
2509 }
2510
2511 systable_endscan(conscan);
2512 heap_close(conDesc, RowExclusiveLock);
2513
2514 return found;
2515 }
2516
2517 /*
2518 * Update the count of constraints in the relation's pg_class tuple.
2519 *
2520 * Caller had better hold exclusive lock on the relation.
2521 *
2522 * An important side effect is that a SI update message will be sent out for
2523 * the pg_class tuple, which will force other backends to rebuild their
2524 * relcache entries for the rel. Also, this backend will rebuild its
2525 * own relcache entry at the next CommandCounterIncrement.
2526 */
2527 static void
SetRelationNumChecks(Relation rel,int numchecks)2528 SetRelationNumChecks(Relation rel, int numchecks)
2529 {
2530 Relation relrel;
2531 HeapTuple reltup;
2532 Form_pg_class relStruct;
2533
2534 relrel = heap_open(RelationRelationId, RowExclusiveLock);
2535 reltup = SearchSysCacheCopy1(RELOID,
2536 ObjectIdGetDatum(RelationGetRelid(rel)));
2537 if (!HeapTupleIsValid(reltup))
2538 elog(ERROR, "cache lookup failed for relation %u",
2539 RelationGetRelid(rel));
2540 relStruct = (Form_pg_class) GETSTRUCT(reltup);
2541
2542 if (relStruct->relchecks != numchecks)
2543 {
2544 relStruct->relchecks = numchecks;
2545
2546 simple_heap_update(relrel, &reltup->t_self, reltup);
2547
2548 /* keep catalog indexes current */
2549 CatalogUpdateIndexes(relrel, reltup);
2550 }
2551 else
2552 {
2553 /* Skip the disk update, but force relcache inval anyway */
2554 CacheInvalidateRelcache(rel);
2555 }
2556
2557 heap_freetuple(reltup);
2558 heap_close(relrel, RowExclusiveLock);
2559 }
2560
2561 /*
2562 * Take a raw default and convert it to a cooked format ready for
2563 * storage.
2564 *
2565 * Parse state should be set up to recognize any vars that might appear
2566 * in the expression. (Even though we plan to reject vars, it's more
2567 * user-friendly to give the correct error message than "unknown var".)
2568 *
2569 * If atttypid is not InvalidOid, coerce the expression to the specified
2570 * type (and typmod atttypmod). attname is only needed in this case:
2571 * it is used in the error message, if any.
2572 */
2573 Node *
cookDefault(ParseState * pstate,Node * raw_default,Oid atttypid,int32 atttypmod,char * attname)2574 cookDefault(ParseState *pstate,
2575 Node *raw_default,
2576 Oid atttypid,
2577 int32 atttypmod,
2578 char *attname)
2579 {
2580 Node *expr;
2581
2582 Assert(raw_default != NULL);
2583
2584 /*
2585 * Transform raw parsetree to executable expression.
2586 */
2587 expr = transformExpr(pstate, raw_default, EXPR_KIND_COLUMN_DEFAULT);
2588
2589 /*
2590 * Make sure default expr does not refer to any vars (we need this check
2591 * since the pstate includes the target table).
2592 */
2593 if (contain_var_clause(expr))
2594 ereport(ERROR,
2595 (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
2596 errmsg("cannot use column references in default expression")));
2597
2598 /*
2599 * transformExpr() should have already rejected subqueries, aggregates,
2600 * and window functions, based on the EXPR_KIND_ for a default expression.
2601 *
2602 * It can't return a set either.
2603 */
2604 if (expression_returns_set(expr))
2605 ereport(ERROR,
2606 (errcode(ERRCODE_DATATYPE_MISMATCH),
2607 errmsg("default expression must not return a set")));
2608
2609 /*
2610 * Coerce the expression to the correct type and typmod, if given. This
2611 * should match the parser's processing of non-defaulted expressions ---
2612 * see transformAssignedExpr().
2613 */
2614 if (OidIsValid(atttypid))
2615 {
2616 Oid type_id = exprType(expr);
2617
2618 expr = coerce_to_target_type(pstate, expr, type_id,
2619 atttypid, atttypmod,
2620 COERCION_ASSIGNMENT,
2621 COERCE_IMPLICIT_CAST,
2622 -1);
2623 if (expr == NULL)
2624 ereport(ERROR,
2625 (errcode(ERRCODE_DATATYPE_MISMATCH),
2626 errmsg("column \"%s\" is of type %s"
2627 " but default expression is of type %s",
2628 attname,
2629 format_type_be(atttypid),
2630 format_type_be(type_id)),
2631 errhint("You will need to rewrite or cast the expression.")));
2632 }
2633
2634 /*
2635 * Finally, take care of collations in the finished expression.
2636 */
2637 assign_expr_collations(pstate, expr);
2638
2639 return expr;
2640 }
2641
2642 /*
2643 * Take a raw CHECK constraint expression and convert it to a cooked format
2644 * ready for storage.
2645 *
2646 * Parse state must be set up to recognize any vars that might appear
2647 * in the expression.
2648 */
2649 static Node *
cookConstraint(ParseState * pstate,Node * raw_constraint,char * relname)2650 cookConstraint(ParseState *pstate,
2651 Node *raw_constraint,
2652 char *relname)
2653 {
2654 Node *expr;
2655
2656 /*
2657 * Transform raw parsetree to executable expression.
2658 */
2659 expr = transformExpr(pstate, raw_constraint, EXPR_KIND_CHECK_CONSTRAINT);
2660
2661 /*
2662 * Make sure it yields a boolean result.
2663 */
2664 expr = coerce_to_boolean(pstate, expr, "CHECK");
2665
2666 /*
2667 * Take care of collations.
2668 */
2669 assign_expr_collations(pstate, expr);
2670
2671 /*
2672 * Make sure no outside relations are referred to (this is probably dead
2673 * code now that add_missing_from is history).
2674 */
2675 if (list_length(pstate->p_rtable) != 1)
2676 ereport(ERROR,
2677 (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
2678 errmsg("only table \"%s\" can be referenced in check constraint",
2679 relname)));
2680
2681 return expr;
2682 }
2683
2684
2685 /*
2686 * RemoveStatistics --- remove entries in pg_statistic for a rel or column
2687 *
2688 * If attnum is zero, remove all entries for rel; else remove only the one(s)
2689 * for that column.
2690 */
2691 void
RemoveStatistics(Oid relid,AttrNumber attnum)2692 RemoveStatistics(Oid relid, AttrNumber attnum)
2693 {
2694 Relation pgstatistic;
2695 SysScanDesc scan;
2696 ScanKeyData key[2];
2697 int nkeys;
2698 HeapTuple tuple;
2699
2700 pgstatistic = heap_open(StatisticRelationId, RowExclusiveLock);
2701
2702 ScanKeyInit(&key[0],
2703 Anum_pg_statistic_starelid,
2704 BTEqualStrategyNumber, F_OIDEQ,
2705 ObjectIdGetDatum(relid));
2706
2707 if (attnum == 0)
2708 nkeys = 1;
2709 else
2710 {
2711 ScanKeyInit(&key[1],
2712 Anum_pg_statistic_staattnum,
2713 BTEqualStrategyNumber, F_INT2EQ,
2714 Int16GetDatum(attnum));
2715 nkeys = 2;
2716 }
2717
2718 scan = systable_beginscan(pgstatistic, StatisticRelidAttnumInhIndexId, true,
2719 NULL, nkeys, key);
2720
2721 /* we must loop even when attnum != 0, in case of inherited stats */
2722 while (HeapTupleIsValid(tuple = systable_getnext(scan)))
2723 simple_heap_delete(pgstatistic, &tuple->t_self);
2724
2725 systable_endscan(scan);
2726
2727 heap_close(pgstatistic, RowExclusiveLock);
2728 }
2729
2730
2731 /*
2732 * RelationTruncateIndexes - truncate all indexes associated
2733 * with the heap relation to zero tuples.
2734 *
2735 * The routine will truncate and then reconstruct the indexes on
2736 * the specified relation. Caller must hold exclusive lock on rel.
2737 */
2738 static void
RelationTruncateIndexes(Relation heapRelation)2739 RelationTruncateIndexes(Relation heapRelation)
2740 {
2741 ListCell *indlist;
2742
2743 /* Ask the relcache to produce a list of the indexes of the rel */
2744 foreach(indlist, RelationGetIndexList(heapRelation))
2745 {
2746 Oid indexId = lfirst_oid(indlist);
2747 Relation currentIndex;
2748 IndexInfo *indexInfo;
2749
2750 /* Open the index relation; use exclusive lock, just to be sure */
2751 currentIndex = index_open(indexId, AccessExclusiveLock);
2752
2753 /*
2754 * Fetch info needed for index_build. Since we know there are no
2755 * tuples that actually need indexing, we can use a dummy IndexInfo.
2756 * This is slightly cheaper to build, but the real point is to avoid
2757 * possibly running user-defined code in index expressions or
2758 * predicates. We might be getting invoked during ON COMMIT
2759 * processing, and we don't want to run any such code then.
2760 */
2761 indexInfo = BuildDummyIndexInfo(currentIndex);
2762
2763 /*
2764 * Now truncate the actual file (and discard buffers).
2765 */
2766 RelationTruncate(currentIndex, 0);
2767
2768 /* Initialize the index and rebuild */
2769 /* Note: we do not need to re-establish pkey setting */
2770 index_build(heapRelation, currentIndex, indexInfo, false, true);
2771
2772 /* We're done with this index */
2773 index_close(currentIndex, NoLock);
2774 }
2775 }
2776
2777 /*
2778 * heap_truncate
2779 *
2780 * This routine deletes all data within all the specified relations.
2781 *
2782 * This is not transaction-safe! There is another, transaction-safe
2783 * implementation in commands/tablecmds.c. We now use this only for
2784 * ON COMMIT truncation of temporary tables, where it doesn't matter.
2785 */
2786 void
heap_truncate(List * relids)2787 heap_truncate(List *relids)
2788 {
2789 List *relations = NIL;
2790 ListCell *cell;
2791
2792 /* Open relations for processing, and grab exclusive access on each */
2793 foreach(cell, relids)
2794 {
2795 Oid rid = lfirst_oid(cell);
2796 Relation rel;
2797
2798 rel = heap_open(rid, AccessExclusiveLock);
2799 relations = lappend(relations, rel);
2800 }
2801
2802 /* Don't allow truncate on tables that are referenced by foreign keys */
2803 heap_truncate_check_FKs(relations, true);
2804
2805 /* OK to do it */
2806 foreach(cell, relations)
2807 {
2808 Relation rel = lfirst(cell);
2809
2810 /* Truncate the relation */
2811 heap_truncate_one_rel(rel);
2812
2813 /* Close the relation, but keep exclusive lock on it until commit */
2814 heap_close(rel, NoLock);
2815 }
2816 }
2817
2818 /*
2819 * heap_truncate_one_rel
2820 *
2821 * This routine deletes all data within the specified relation.
2822 *
2823 * This is not transaction-safe, because the truncation is done immediately
2824 * and cannot be rolled back later. Caller is responsible for having
2825 * checked permissions etc, and must have obtained AccessExclusiveLock.
2826 */
2827 void
heap_truncate_one_rel(Relation rel)2828 heap_truncate_one_rel(Relation rel)
2829 {
2830 Oid toastrelid;
2831
2832 /* Truncate the actual file (and discard buffers) */
2833 RelationTruncate(rel, 0);
2834
2835 /* If the relation has indexes, truncate the indexes too */
2836 RelationTruncateIndexes(rel);
2837
2838 /* If there is a toast table, truncate that too */
2839 toastrelid = rel->rd_rel->reltoastrelid;
2840 if (OidIsValid(toastrelid))
2841 {
2842 Relation toastrel = heap_open(toastrelid, AccessExclusiveLock);
2843
2844 RelationTruncate(toastrel, 0);
2845 RelationTruncateIndexes(toastrel);
2846 /* keep the lock... */
2847 heap_close(toastrel, NoLock);
2848 }
2849 }
2850
2851 /*
2852 * heap_truncate_check_FKs
2853 * Check for foreign keys referencing a list of relations that
2854 * are to be truncated, and raise error if there are any
2855 *
2856 * We disallow such FKs (except self-referential ones) since the whole point
2857 * of TRUNCATE is to not scan the individual rows to be thrown away.
2858 *
2859 * This is split out so it can be shared by both implementations of truncate.
2860 * Caller should already hold a suitable lock on the relations.
2861 *
2862 * tempTables is only used to select an appropriate error message.
2863 */
2864 void
heap_truncate_check_FKs(List * relations,bool tempTables)2865 heap_truncate_check_FKs(List *relations, bool tempTables)
2866 {
2867 List *oids = NIL;
2868 List *dependents;
2869 ListCell *cell;
2870
2871 /*
2872 * Build a list of OIDs of the interesting relations.
2873 *
2874 * If a relation has no triggers, then it can neither have FKs nor be
2875 * referenced by a FK from another table, so we can ignore it.
2876 */
2877 foreach(cell, relations)
2878 {
2879 Relation rel = lfirst(cell);
2880
2881 if (rel->rd_rel->relhastriggers)
2882 oids = lappend_oid(oids, RelationGetRelid(rel));
2883 }
2884
2885 /*
2886 * Fast path: if no relation has triggers, none has FKs either.
2887 */
2888 if (oids == NIL)
2889 return;
2890
2891 /*
2892 * Otherwise, must scan pg_constraint. We make one pass with all the
2893 * relations considered; if this finds nothing, then all is well.
2894 */
2895 dependents = heap_truncate_find_FKs(oids);
2896 if (dependents == NIL)
2897 return;
2898
2899 /*
2900 * Otherwise we repeat the scan once per relation to identify a particular
2901 * pair of relations to complain about. This is pretty slow, but
2902 * performance shouldn't matter much in a failure path. The reason for
2903 * doing things this way is to ensure that the message produced is not
2904 * dependent on chance row locations within pg_constraint.
2905 */
2906 foreach(cell, oids)
2907 {
2908 Oid relid = lfirst_oid(cell);
2909 ListCell *cell2;
2910
2911 dependents = heap_truncate_find_FKs(list_make1_oid(relid));
2912
2913 foreach(cell2, dependents)
2914 {
2915 Oid relid2 = lfirst_oid(cell2);
2916
2917 if (!list_member_oid(oids, relid2))
2918 {
2919 char *relname = get_rel_name(relid);
2920 char *relname2 = get_rel_name(relid2);
2921
2922 if (tempTables)
2923 ereport(ERROR,
2924 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2925 errmsg("unsupported ON COMMIT and foreign key combination"),
2926 errdetail("Table \"%s\" references \"%s\", but they do not have the same ON COMMIT setting.",
2927 relname2, relname)));
2928 else
2929 ereport(ERROR,
2930 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2931 errmsg("cannot truncate a table referenced in a foreign key constraint"),
2932 errdetail("Table \"%s\" references \"%s\".",
2933 relname2, relname),
2934 errhint("Truncate table \"%s\" at the same time, "
2935 "or use TRUNCATE ... CASCADE.",
2936 relname2)));
2937 }
2938 }
2939 }
2940 }
2941
2942 /*
2943 * heap_truncate_find_FKs
2944 * Find relations having foreign keys referencing any of the given rels
2945 *
2946 * Input and result are both lists of relation OIDs. The result contains
2947 * no duplicates, does *not* include any rels that were already in the input
2948 * list, and is sorted in OID order. (The last property is enforced mainly
2949 * to guarantee consistent behavior in the regression tests; we don't want
2950 * behavior to change depending on chance locations of rows in pg_constraint.)
2951 *
2952 * Note: caller should already have appropriate lock on all rels mentioned
2953 * in relationIds. Since adding or dropping an FK requires exclusive lock
2954 * on both rels, this ensures that the answer will be stable.
2955 */
2956 List *
heap_truncate_find_FKs(List * relationIds)2957 heap_truncate_find_FKs(List *relationIds)
2958 {
2959 List *result = NIL;
2960 Relation fkeyRel;
2961 SysScanDesc fkeyScan;
2962 HeapTuple tuple;
2963
2964 /*
2965 * Must scan pg_constraint. Right now, it is a seqscan because there is
2966 * no available index on confrelid.
2967 */
2968 fkeyRel = heap_open(ConstraintRelationId, AccessShareLock);
2969
2970 fkeyScan = systable_beginscan(fkeyRel, InvalidOid, false,
2971 NULL, 0, NULL);
2972
2973 while (HeapTupleIsValid(tuple = systable_getnext(fkeyScan)))
2974 {
2975 Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(tuple);
2976
2977 /* Not a foreign key */
2978 if (con->contype != CONSTRAINT_FOREIGN)
2979 continue;
2980
2981 /* Not referencing one of our list of tables */
2982 if (!list_member_oid(relationIds, con->confrelid))
2983 continue;
2984
2985 /* Add referencer unless already in input or result list */
2986 if (!list_member_oid(relationIds, con->conrelid))
2987 result = insert_ordered_unique_oid(result, con->conrelid);
2988 }
2989
2990 systable_endscan(fkeyScan);
2991 heap_close(fkeyRel, AccessShareLock);
2992
2993 return result;
2994 }
2995
2996 /*
2997 * insert_ordered_unique_oid
2998 * Insert a new Oid into a sorted list of Oids, preserving ordering,
2999 * and eliminating duplicates
3000 *
3001 * Building the ordered list this way is O(N^2), but with a pretty small
3002 * constant, so for the number of entries we expect it will probably be
3003 * faster than trying to apply qsort(). It seems unlikely someone would be
3004 * trying to truncate a table with thousands of dependent tables ...
3005 */
3006 static List *
insert_ordered_unique_oid(List * list,Oid datum)3007 insert_ordered_unique_oid(List *list, Oid datum)
3008 {
3009 ListCell *prev;
3010
3011 /* Does the datum belong at the front? */
3012 if (list == NIL || datum < linitial_oid(list))
3013 return lcons_oid(datum, list);
3014 /* Does it match the first entry? */
3015 if (datum == linitial_oid(list))
3016 return list; /* duplicate, so don't insert */
3017 /* No, so find the entry it belongs after */
3018 prev = list_head(list);
3019 for (;;)
3020 {
3021 ListCell *curr = lnext(prev);
3022
3023 if (curr == NULL || datum < lfirst_oid(curr))
3024 break; /* it belongs after 'prev', before 'curr' */
3025
3026 if (datum == lfirst_oid(curr))
3027 return list; /* duplicate, so don't insert */
3028
3029 prev = curr;
3030 }
3031 /* Insert datum into list after 'prev' */
3032 lappend_cell_oid(list, prev, datum);
3033 return list;
3034 }
3035