1/*-------------------------------------------------------------------------
2 *
3 * tablecmds.c
4 * Commands for creating and altering table structures and settings
5 *
6 * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
7 * Portions Copyright (c) 1994, Regents of the University of California
8 *
9 *
10 * IDENTIFICATION
11 * src/backend/commands/tablecmds.c
12 *
13 *-------------------------------------------------------------------------
14 */
15#include "postgres.h"
16
17#include "access/genam.h"
18#include "access/heapam.h"
19#include "access/heapam_xlog.h"
20#include "access/multixact.h"
21#include "access/reloptions.h"
22#include "access/relscan.h"
23#include "access/tableam.h"
24#include "access/sysattr.h"
25#include "access/tableam.h"
26#include "access/tupconvert.h"
27#include "access/xact.h"
28#include "access/xlog.h"
29#include "catalog/catalog.h"
30#include "catalog/dependency.h"
31#include "catalog/heap.h"
32#include "catalog/index.h"
33#include "catalog/indexing.h"
34#include "catalog/namespace.h"
35#include "catalog/objectaccess.h"
36#include "catalog/partition.h"
37#include "catalog/pg_am.h"
38#include "catalog/pg_collation.h"
39#include "catalog/pg_constraint.h"
40#include "catalog/pg_depend.h"
41#include "catalog/pg_foreign_table.h"
42#include "catalog/pg_inherits.h"
43#include "catalog/pg_namespace.h"
44#include "catalog/pg_opclass.h"
45#include "catalog/pg_tablespace.h"
46#include "catalog/pg_trigger.h"
47#include "catalog/pg_type.h"
48#include "catalog/storage.h"
49#include "catalog/storage_xlog.h"
50#include "catalog/toasting.h"
51#include "commands/cluster.h"
52#include "commands/comment.h"
53#include "commands/defrem.h"
54#include "commands/event_trigger.h"
55#include "commands/policy.h"
56#include "commands/sequence.h"
57#include "commands/tablecmds.h"
58#include "commands/tablespace.h"
59#include "commands/trigger.h"
60#include "commands/typecmds.h"
61#include "commands/user.h"
62#include "executor/executor.h"
63#include "foreign/foreign.h"
64#include "miscadmin.h"
65#include "nodes/makefuncs.h"
66#include "nodes/nodeFuncs.h"
67#include "nodes/parsenodes.h"
68#include "optimizer/optimizer.h"
69#include "parser/parse_clause.h"
70#include "parser/parse_coerce.h"
71#include "parser/parse_collate.h"
72#include "parser/parse_expr.h"
73#include "parser/parse_oper.h"
74#include "parser/parse_relation.h"
75#include "parser/parse_type.h"
76#include "parser/parse_utilcmd.h"
77#include "parser/parser.h"
78#include "partitioning/partbounds.h"
79#include "partitioning/partdesc.h"
80#include "pgstat.h"
81#include "rewrite/rewriteDefine.h"
82#include "rewrite/rewriteHandler.h"
83#include "rewrite/rewriteManip.h"
84#include "storage/bufmgr.h"
85#include "storage/lmgr.h"
86#include "storage/lock.h"
87#include "storage/predicate.h"
88#include "storage/smgr.h"
89#include "utils/acl.h"
90#include "utils/builtins.h"
91#include "utils/fmgroids.h"
92#include "utils/inval.h"
93#include "utils/lsyscache.h"
94#include "utils/memutils.h"
95#include "utils/partcache.h"
96#include "utils/relcache.h"
97#include "utils/ruleutils.h"
98#include "utils/snapmgr.h"
99#include "utils/syscache.h"
100#include "utils/timestamp.h"
101#include "utils/typcache.h"
102
103
104/*
105 * ON COMMIT action list
106 */
107typedef struct OnCommitItem
108{
109 Oid relid; /* relid of relation */
110 OnCommitAction oncommit; /* what to do at end of xact */
111
112 /*
113 * If this entry was created during the current transaction,
114 * creating_subid is the ID of the creating subxact; if created in a prior
115 * transaction, creating_subid is zero. If deleted during the current
116 * transaction, deleting_subid is the ID of the deleting subxact; if no
117 * deletion request is pending, deleting_subid is zero.
118 */
119 SubTransactionId creating_subid;
120 SubTransactionId deleting_subid;
121} OnCommitItem;
122
123static List *on_commits = NIL;
124
125
126/*
127 * State information for ALTER TABLE
128 *
129 * The pending-work queue for an ALTER TABLE is a List of AlteredTableInfo
130 * structs, one for each table modified by the operation (the named table
131 * plus any child tables that are affected). We save lists of subcommands
132 * to apply to this table (possibly modified by parse transformation steps);
133 * these lists will be executed in Phase 2. If a Phase 3 step is needed,
134 * necessary information is stored in the constraints and newvals lists.
135 *
136 * Phase 2 is divided into multiple passes; subcommands are executed in
137 * a pass determined by subcommand type.
138 */
139
140#define AT_PASS_UNSET -1 /* UNSET will cause ERROR */
141#define AT_PASS_DROP 0 /* DROP (all flavors) */
142#define AT_PASS_ALTER_TYPE 1 /* ALTER COLUMN TYPE */
143#define AT_PASS_OLD_INDEX 2 /* re-add existing indexes */
144#define AT_PASS_OLD_CONSTR 3 /* re-add existing constraints */
145/* We could support a RENAME COLUMN pass here, but not currently used */
146#define AT_PASS_ADD_COL 4 /* ADD COLUMN */
147#define AT_PASS_COL_ATTRS 5 /* set other column attributes */
148#define AT_PASS_ADD_INDEX 6 /* ADD indexes */
149#define AT_PASS_ADD_CONSTR 7 /* ADD constraints, defaults */
150#define AT_PASS_MISC 8 /* other stuff */
151#define AT_NUM_PASSES 9
152
153typedef struct AlteredTableInfo
154{
155 /* Information saved before any work commences: */
156 Oid relid; /* Relation to work on */
157 char relkind; /* Its relkind */
158 TupleDesc oldDesc; /* Pre-modification tuple descriptor */
159 /* Information saved by Phase 1 for Phase 2: */
160 List *subcmds[AT_NUM_PASSES]; /* Lists of AlterTableCmd */
161 /* Information saved by Phases 1/2 for Phase 3: */
162 List *constraints; /* List of NewConstraint */
163 List *newvals; /* List of NewColumnValue */
164 bool verify_new_notnull; /* T if we should recheck NOT NULL */
165 int rewrite; /* Reason for forced rewrite, if any */
166 Oid newTableSpace; /* new tablespace; 0 means no change */
167 bool chgPersistence; /* T if SET LOGGED/UNLOGGED is used */
168 char newrelpersistence; /* if above is true */
169 Expr *partition_constraint; /* for attach partition validation */
170 /* true, if validating default due to some other attach/detach */
171 bool validate_default;
172 /* Objects to rebuild after completing ALTER TYPE operations */
173 List *changedConstraintOids; /* OIDs of constraints to rebuild */
174 List *changedConstraintDefs; /* string definitions of same */
175 List *changedIndexOids; /* OIDs of indexes to rebuild */
176 List *changedIndexDefs; /* string definitions of same */
177} AlteredTableInfo;
178
179/* Struct describing one new constraint to check in Phase 3 scan */
180/* Note: new NOT NULL constraints are handled elsewhere */
181typedef struct NewConstraint
182{
183 char *name; /* Constraint name, or NULL if none */
184 ConstrType contype; /* CHECK or FOREIGN */
185 Oid refrelid; /* PK rel, if FOREIGN */
186 Oid refindid; /* OID of PK's index, if FOREIGN */
187 Oid conid; /* OID of pg_constraint entry, if FOREIGN */
188 Node *qual; /* Check expr or CONSTR_FOREIGN Constraint */
189 ExprState *qualstate; /* Execution state for CHECK expr */
190} NewConstraint;
191
192/*
193 * Struct describing one new column value that needs to be computed during
194 * Phase 3 copy (this could be either a new column with a non-null default, or
195 * a column that we're changing the type of). Columns without such an entry
196 * are just copied from the old table during ATRewriteTable. Note that the
197 * expr is an expression over *old* table values.
198 */
199typedef struct NewColumnValue
200{
201 AttrNumber attnum; /* which column */
202 Expr *expr; /* expression to compute */
203 ExprState *exprstate; /* execution state */
204} NewColumnValue;
205
206/*
207 * Error-reporting support for RemoveRelations
208 */
209struct dropmsgstrings
210{
211 char kind;
212 int nonexistent_code;
213 const char *nonexistent_msg;
214 const char *skipping_msg;
215 const char *nota_msg;
216 const char *drophint_msg;
217};
218
219static const struct dropmsgstrings dropmsgstringarray[] = {
220 {RELKIND_RELATION,
221 ERRCODE_UNDEFINED_TABLE,
222 gettext_noop("table \"%s\" does not exist"),
223 gettext_noop("table \"%s\" does not exist, skipping"),
224 gettext_noop("\"%s\" is not a table"),
225 gettext_noop("Use DROP TABLE to remove a table.")},
226 {RELKIND_SEQUENCE,
227 ERRCODE_UNDEFINED_TABLE,
228 gettext_noop("sequence \"%s\" does not exist"),
229 gettext_noop("sequence \"%s\" does not exist, skipping"),
230 gettext_noop("\"%s\" is not a sequence"),
231 gettext_noop("Use DROP SEQUENCE to remove a sequence.")},
232 {RELKIND_VIEW,
233 ERRCODE_UNDEFINED_TABLE,
234 gettext_noop("view \"%s\" does not exist"),
235 gettext_noop("view \"%s\" does not exist, skipping"),
236 gettext_noop("\"%s\" is not a view"),
237 gettext_noop("Use DROP VIEW to remove a view.")},
238 {RELKIND_MATVIEW,
239 ERRCODE_UNDEFINED_TABLE,
240 gettext_noop("materialized view \"%s\" does not exist"),
241 gettext_noop("materialized view \"%s\" does not exist, skipping"),
242 gettext_noop("\"%s\" is not a materialized view"),
243 gettext_noop("Use DROP MATERIALIZED VIEW to remove a materialized view.")},
244 {RELKIND_INDEX,
245 ERRCODE_UNDEFINED_OBJECT,
246 gettext_noop("index \"%s\" does not exist"),
247 gettext_noop("index \"%s\" does not exist, skipping"),
248 gettext_noop("\"%s\" is not an index"),
249 gettext_noop("Use DROP INDEX to remove an index.")},
250 {RELKIND_COMPOSITE_TYPE,
251 ERRCODE_UNDEFINED_OBJECT,
252 gettext_noop("type \"%s\" does not exist"),
253 gettext_noop("type \"%s\" does not exist, skipping"),
254 gettext_noop("\"%s\" is not a type"),
255 gettext_noop("Use DROP TYPE to remove a type.")},
256 {RELKIND_FOREIGN_TABLE,
257 ERRCODE_UNDEFINED_OBJECT,
258 gettext_noop("foreign table \"%s\" does not exist"),
259 gettext_noop("foreign table \"%s\" does not exist, skipping"),
260 gettext_noop("\"%s\" is not a foreign table"),
261 gettext_noop("Use DROP FOREIGN TABLE to remove a foreign table.")},
262 {RELKIND_PARTITIONED_TABLE,
263 ERRCODE_UNDEFINED_TABLE,
264 gettext_noop("table \"%s\" does not exist"),
265 gettext_noop("table \"%s\" does not exist, skipping"),
266 gettext_noop("\"%s\" is not a table"),
267 gettext_noop("Use DROP TABLE to remove a table.")},
268 {RELKIND_PARTITIONED_INDEX,
269 ERRCODE_UNDEFINED_OBJECT,
270 gettext_noop("index \"%s\" does not exist"),
271 gettext_noop("index \"%s\" does not exist, skipping"),
272 gettext_noop("\"%s\" is not an index"),
273 gettext_noop("Use DROP INDEX to remove an index.")},
274 {'\0', 0, NULL, NULL, NULL, NULL}
275};
276
277struct DropRelationCallbackState
278{
279 char relkind;
280 Oid heapOid;
281 Oid partParentOid;
282 bool concurrent;
283};
284
285/* Alter table target-type flags for ATSimplePermissions */
286#define ATT_TABLE 0x0001
287#define ATT_VIEW 0x0002
288#define ATT_MATVIEW 0x0004
289#define ATT_INDEX 0x0008
290#define ATT_COMPOSITE_TYPE 0x0010
291#define ATT_FOREIGN_TABLE 0x0020
292#define ATT_PARTITIONED_INDEX 0x0040
293
294/*
295 * Partition tables are expected to be dropped when the parent partitioned
296 * table gets dropped. Hence for partitioning we use AUTO dependency.
297 * Otherwise, for regular inheritance use NORMAL dependency.
298 */
299#define child_dependency_type(child_is_partition) \
300 ((child_is_partition) ? DEPENDENCY_AUTO : DEPENDENCY_NORMAL)
301
302static void truncate_check_rel(Oid relid, Form_pg_class reltuple);
303static void truncate_check_activity(Relation rel);
304static void RangeVarCallbackForTruncate(const RangeVar *relation,
305 Oid relId, Oid oldRelId, void *arg);
306static List *MergeAttributes(List *schema, List *supers, char relpersistence,
307 bool is_partition, List **supconstr);
308static bool MergeCheckConstraint(List *constraints, char *name, Node *expr);
309static void MergeAttributesIntoExisting(Relation child_rel, Relation parent_rel);
310static void MergeConstraintsIntoExisting(Relation child_rel, Relation parent_rel);
311static void StoreCatalogInheritance(Oid relationId, List *supers,
312 bool child_is_partition);
313static void StoreCatalogInheritance1(Oid relationId, Oid parentOid,
314 int32 seqNumber, Relation inhRelation,
315 bool child_is_partition);
316static int findAttrByName(const char *attributeName, List *schema);
317static void AlterIndexNamespaces(Relation classRel, Relation rel,
318 Oid oldNspOid, Oid newNspOid, ObjectAddresses *objsMoved);
319static void AlterSeqNamespaces(Relation classRel, Relation rel,
320 Oid oldNspOid, Oid newNspOid, ObjectAddresses *objsMoved,
321 LOCKMODE lockmode);
322static ObjectAddress ATExecAlterConstraint(Relation rel, AlterTableCmd *cmd,
323 bool recurse, bool recursing, LOCKMODE lockmode);
324static ObjectAddress ATExecValidateConstraint(Relation rel, char *constrName,
325 bool recurse, bool recursing, LOCKMODE lockmode);
326static int transformColumnNameList(Oid relId, List *colList,
327 int16 *attnums, Oid *atttypids);
328static int transformFkeyGetPrimaryKey(Relation pkrel, Oid *indexOid,
329 List **attnamelist,
330 int16 *attnums, Oid *atttypids,
331 Oid *opclasses);
332static Oid transformFkeyCheckAttrs(Relation pkrel,
333 int numattrs, int16 *attnums,
334 Oid *opclasses);
335static void checkFkeyPermissions(Relation rel, int16 *attnums, int natts);
336static CoercionPathType findFkeyCast(Oid targetTypeId, Oid sourceTypeId,
337 Oid *funcid);
338static void validateCheckConstraint(Relation rel, HeapTuple constrtup);
339static void validateForeignKeyConstraint(char *conname,
340 Relation rel, Relation pkrel,
341 Oid pkindOid, Oid constraintOid);
342static void ATController(AlterTableStmt *parsetree,
343 Relation rel, List *cmds, bool recurse, LOCKMODE lockmode);
344static void ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
345 bool recurse, bool recursing, LOCKMODE lockmode);
346static void ATRewriteCatalogs(List **wqueue, LOCKMODE lockmode);
347static void ATExecCmd(List **wqueue, AlteredTableInfo *tab, Relation rel,
348 AlterTableCmd *cmd, LOCKMODE lockmode);
349static void ATRewriteTables(AlterTableStmt *parsetree,
350 List **wqueue, LOCKMODE lockmode);
351static void ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap, LOCKMODE lockmode);
352static AlteredTableInfo *ATGetQueueEntry(List **wqueue, Relation rel);
353static void ATSimplePermissions(Relation rel, int allowed_targets);
354static void ATWrongRelkindError(Relation rel, int allowed_targets);
355static void ATSimpleRecursion(List **wqueue, Relation rel,
356 AlterTableCmd *cmd, bool recurse, LOCKMODE lockmode);
357static void ATCheckPartitionsNotInUse(Relation rel, LOCKMODE lockmode);
358static void ATTypedTableRecursion(List **wqueue, Relation rel, AlterTableCmd *cmd,
359 LOCKMODE lockmode);
360static List *find_typed_table_dependencies(Oid typeOid, const char *typeName,
361 DropBehavior behavior);
362static void ATPrepAddColumn(List **wqueue, Relation rel, bool recurse, bool recursing,
363 bool is_view, AlterTableCmd *cmd, LOCKMODE lockmode);
364static ObjectAddress ATExecAddColumn(List **wqueue, AlteredTableInfo *tab,
365 Relation rel, ColumnDef *colDef,
366 bool recurse, bool recursing,
367 bool if_not_exists, LOCKMODE lockmode);
368static bool check_for_column_name_collision(Relation rel, const char *colname,
369 bool if_not_exists);
370static void add_column_datatype_dependency(Oid relid, int32 attnum, Oid typid);
371static void add_column_collation_dependency(Oid relid, int32 attnum, Oid collid);
372static void ATPrepDropNotNull(Relation rel, bool recurse, bool recursing);
373static ObjectAddress ATExecDropNotNull(Relation rel, const char *colName, LOCKMODE lockmode);
374static void ATPrepSetNotNull(List **wqueue, Relation rel,
375 AlterTableCmd *cmd, bool recurse, bool recursing,
376 LOCKMODE lockmode);
377static ObjectAddress ATExecSetNotNull(AlteredTableInfo *tab, Relation rel,
378 const char *colName, LOCKMODE lockmode);
379static void ATExecCheckNotNull(AlteredTableInfo *tab, Relation rel,
380 const char *colName, LOCKMODE lockmode);
381static bool NotNullImpliedByRelConstraints(Relation rel, Form_pg_attribute attr);
382static bool ConstraintImpliedByRelConstraint(Relation scanrel,
383 List *testConstraint, List *provenConstraint);
384static ObjectAddress ATExecColumnDefault(Relation rel, const char *colName,
385 Node *newDefault, LOCKMODE lockmode);
386static ObjectAddress ATExecAddIdentity(Relation rel, const char *colName,
387 Node *def, LOCKMODE lockmode);
388static ObjectAddress ATExecSetIdentity(Relation rel, const char *colName,
389 Node *def, LOCKMODE lockmode);
390static ObjectAddress ATExecDropIdentity(Relation rel, const char *colName, bool missing_ok, LOCKMODE lockmode);
391static void ATPrepSetStatistics(Relation rel, const char *colName, int16 colNum,
392 Node *newValue, LOCKMODE lockmode);
393static ObjectAddress ATExecSetStatistics(Relation rel, const char *colName, int16 colNum,
394 Node *newValue, LOCKMODE lockmode);
395static ObjectAddress ATExecSetOptions(Relation rel, const char *colName,
396 Node *options, bool isReset, LOCKMODE lockmode);
397static ObjectAddress ATExecSetStorage(Relation rel, const char *colName,
398 Node *newValue, LOCKMODE lockmode);
399static void ATPrepDropColumn(List **wqueue, Relation rel, bool recurse, bool recursing,
400 AlterTableCmd *cmd, LOCKMODE lockmode);
401static ObjectAddress ATExecDropColumn(List **wqueue, Relation rel, const char *colName,
402 DropBehavior behavior,
403 bool recurse, bool recursing,
404 bool missing_ok, LOCKMODE lockmode);
405static ObjectAddress ATExecAddIndex(AlteredTableInfo *tab, Relation rel,
406 IndexStmt *stmt, bool is_rebuild, LOCKMODE lockmode);
407static ObjectAddress ATExecAddConstraint(List **wqueue,
408 AlteredTableInfo *tab, Relation rel,
409 Constraint *newConstraint, bool recurse, bool is_readd,
410 LOCKMODE lockmode);
411static char *ChooseForeignKeyConstraintNameAddition(List *colnames);
412static ObjectAddress ATExecAddIndexConstraint(AlteredTableInfo *tab, Relation rel,
413 IndexStmt *stmt, LOCKMODE lockmode);
414static ObjectAddress ATAddCheckConstraint(List **wqueue,
415 AlteredTableInfo *tab, Relation rel,
416 Constraint *constr,
417 bool recurse, bool recursing, bool is_readd,
418 LOCKMODE lockmode);
419static ObjectAddress ATAddForeignKeyConstraint(List **wqueue, AlteredTableInfo *tab,
420 Relation rel, Constraint *fkconstraint, Oid parentConstr,
421 bool recurse, bool recursing,
422 LOCKMODE lockmode);
423static ObjectAddress addFkRecurseReferenced(List **wqueue, Constraint *fkconstraint,
424 Relation rel, Relation pkrel, Oid indexOid, Oid parentConstr,
425 int numfks, int16 *pkattnum, int16 *fkattnum,
426 Oid *pfeqoperators, Oid *ppeqoperators, Oid *ffeqoperators,
427 bool old_check_ok);
428static void addFkRecurseReferencing(List **wqueue, Constraint *fkconstraint,
429 Relation rel, Relation pkrel, Oid indexOid, Oid parentConstr,
430 int numfks, int16 *pkattnum, int16 *fkattnum,
431 Oid *pfeqoperators, Oid *ppeqoperators, Oid *ffeqoperators,
432 bool old_check_ok, LOCKMODE lockmode);
433static void CloneForeignKeyConstraints(List **wqueue, Relation parentRel,
434 Relation partitionRel);
435static void CloneFkReferenced(Relation parentRel, Relation partitionRel);
436static void CloneFkReferencing(List **wqueue, Relation parentRel,
437 Relation partRel);
438static void createForeignKeyCheckTriggers(Oid myRelOid, Oid refRelOid,
439 Constraint *fkconstraint, Oid constraintOid,
440 Oid indexOid);
441static void createForeignKeyActionTriggers(Relation rel, Oid refRelOid,
442 Constraint *fkconstraint, Oid constraintOid,
443 Oid indexOid);
444static bool tryAttachPartitionForeignKey(ForeignKeyCacheInfo *fk,
445 Oid partRelid,
446 Oid parentConstrOid, int numfks,
447 AttrNumber *mapped_conkey, AttrNumber *confkey,
448 Oid *conpfeqop);
449static void ATExecDropConstraint(Relation rel, const char *constrName,
450 DropBehavior behavior,
451 bool recurse, bool recursing,
452 bool missing_ok, LOCKMODE lockmode);
453static void ATPrepAlterColumnType(List **wqueue,
454 AlteredTableInfo *tab, Relation rel,
455 bool recurse, bool recursing,
456 AlterTableCmd *cmd, LOCKMODE lockmode);
457static bool ATColumnChangeRequiresRewrite(Node *expr, AttrNumber varattno);
458static ObjectAddress ATExecAlterColumnType(AlteredTableInfo *tab, Relation rel,
459 AlterTableCmd *cmd, LOCKMODE lockmode);
460static void RememberConstraintForRebuilding(Oid conoid, AlteredTableInfo *tab);
461static void RememberIndexForRebuilding(Oid indoid, AlteredTableInfo *tab);
462static void ATPostAlterTypeCleanup(List **wqueue, AlteredTableInfo *tab,
463 LOCKMODE lockmode);
464static void ATPostAlterTypeParse(Oid oldId, Oid oldRelId, Oid refRelId,
465 char *cmd, List **wqueue, LOCKMODE lockmode,
466 bool rewrite);
467static void RebuildConstraintComment(AlteredTableInfo *tab, int pass,
468 Oid objid, Relation rel, List *domname,
469 const char *conname);
470static void TryReuseIndex(Oid oldId, IndexStmt *stmt);
471static void TryReuseForeignKey(Oid oldId, Constraint *con);
472static ObjectAddress ATExecAlterColumnGenericOptions(Relation rel, const char *colName,
473 List *options, LOCKMODE lockmode);
474static void change_owner_fix_column_acls(Oid relationOid,
475 Oid oldOwnerId, Oid newOwnerId);
476static void change_owner_recurse_to_sequences(Oid relationOid,
477 Oid newOwnerId, LOCKMODE lockmode);
478static ObjectAddress ATExecClusterOn(Relation rel, const char *indexName,
479 LOCKMODE lockmode);
480static void ATExecDropCluster(Relation rel, LOCKMODE lockmode);
481static bool ATPrepChangePersistence(Relation rel, bool toLogged);
482static void ATPrepSetTableSpace(AlteredTableInfo *tab, Relation rel,
483 const char *tablespacename, LOCKMODE lockmode);
484static void ATExecSetTableSpace(Oid tableOid, Oid newTableSpace, LOCKMODE lockmode);
485static void ATExecSetTableSpaceNoStorage(Relation rel, Oid newTableSpace);
486static void ATExecSetRelOptions(Relation rel, List *defList,
487 AlterTableType operation,
488 LOCKMODE lockmode);
489static void ATExecEnableDisableTrigger(Relation rel, const char *trigname,
490 char fires_when, bool skip_system, LOCKMODE lockmode);
491static void ATExecEnableDisableRule(Relation rel, const char *rulename,
492 char fires_when, LOCKMODE lockmode);
493static void ATPrepAddInherit(Relation child_rel);
494static ObjectAddress ATExecAddInherit(Relation child_rel, RangeVar *parent, LOCKMODE lockmode);
495static ObjectAddress ATExecDropInherit(Relation rel, RangeVar *parent, LOCKMODE lockmode);
496static void drop_parent_dependency(Oid relid, Oid refclassid, Oid refobjid,
497 DependencyType deptype);
498static ObjectAddress ATExecAddOf(Relation rel, const TypeName *ofTypename, LOCKMODE lockmode);
499static void ATExecDropOf(Relation rel, LOCKMODE lockmode);
500static void ATExecReplicaIdentity(Relation rel, ReplicaIdentityStmt *stmt, LOCKMODE lockmode);
501static void ATExecGenericOptions(Relation rel, List *options);
502static void ATExecEnableRowSecurity(Relation rel);
503static void ATExecDisableRowSecurity(Relation rel);
504static void ATExecForceNoForceRowSecurity(Relation rel, bool force_rls);
505
506static void index_copy_data(Relation rel, RelFileNode newrnode);
507static const char *storage_name(char c);
508
509static void RangeVarCallbackForDropRelation(const RangeVar *rel, Oid relOid,
510 Oid oldRelOid, void *arg);
511static void RangeVarCallbackForAlterRelation(const RangeVar *rv, Oid relid,
512 Oid oldrelid, void *arg);
513static PartitionSpec *transformPartitionSpec(Relation rel, PartitionSpec *partspec, char *strategy);
514static void ComputePartitionAttrs(ParseState *pstate, Relation rel, List *partParams, AttrNumber *partattrs,
515 List **partexprs, Oid *partopclass, Oid *partcollation, char strategy);
516static void CreateInheritance(Relation child_rel, Relation parent_rel);
517static void RemoveInheritance(Relation child_rel, Relation parent_rel);
518static ObjectAddress ATExecAttachPartition(List **wqueue, Relation rel,
519 PartitionCmd *cmd);
520static void AttachPartitionEnsureIndexes(Relation rel, Relation attachrel);
521static void QueuePartitionConstraintValidation(List **wqueue, Relation scanrel,
522 List *partConstraint,
523 bool validate_default);
524static void CloneRowTriggersToPartition(Relation parent, Relation partition);
525static ObjectAddress ATExecDetachPartition(Relation rel, RangeVar *name);
526static ObjectAddress ATExecAttachPartitionIdx(List **wqueue, Relation rel,
527 RangeVar *name);
528static void validatePartitionedIndex(Relation partedIdx, Relation partedTbl);
529static void refuseDupeIndexAttach(Relation parentIdx, Relation partIdx,
530 Relation partitionTbl);
531static List *GetParentedForeignKeyRefs(Relation partition);
532static void ATDetachCheckNoForeignKeyRefs(Relation partition);
533
534
535/* ----------------------------------------------------------------
536 * DefineRelation
537 * Creates a new relation.
538 *
539 * stmt carries parsetree information from an ordinary CREATE TABLE statement.
540 * The other arguments are used to extend the behavior for other cases:
541 * relkind: relkind to assign to the new relation
542 * ownerId: if not InvalidOid, use this as the new relation's owner.
543 * typaddress: if not null, it's set to the pg_type entry's address.
544 * queryString: for error reporting
545 *
546 * Note that permissions checks are done against current user regardless of
547 * ownerId. A nonzero ownerId is used when someone is creating a relation
548 * "on behalf of" someone else, so we still want to see that the current user
549 * has permissions to do it.
550 *
551 * If successful, returns the address of the new relation.
552 * ----------------------------------------------------------------
553 */
554ObjectAddress
555DefineRelation(CreateStmt *stmt, char relkind, Oid ownerId,
556 ObjectAddress *typaddress, const char *queryString)
557{
558 char relname[NAMEDATALEN];
559 Oid namespaceId;
560 Oid relationId;
561 Oid tablespaceId;
562 Relation rel;
563 TupleDesc descriptor;
564 List *inheritOids;
565 List *old_constraints;
566 List *rawDefaults;
567 List *cookedDefaults;
568 Datum reloptions;
569 ListCell *listptr;
570 AttrNumber attnum;
571 bool partitioned;
572 static char *validnsps[] = HEAP_RELOPT_NAMESPACES;
573 Oid ofTypeId;
574 ObjectAddress address;
575 LOCKMODE parentLockmode;
576 const char *accessMethod = NULL;
577 Oid accessMethodId = InvalidOid;
578
579 /*
580 * Truncate relname to appropriate length (probably a waste of time, as
581 * parser should have done this already).
582 */
583 StrNCpy(relname, stmt->relation->relname, NAMEDATALEN);
584
585 /*
586 * Check consistency of arguments
587 */
588 if (stmt->oncommit != ONCOMMIT_NOOP
589 && stmt->relation->relpersistence != RELPERSISTENCE_TEMP)
590 ereport(ERROR,
591 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
592 errmsg("ON COMMIT can only be used on temporary tables")));
593
594 if (stmt->partspec != NULL)
595 {
596 if (relkind != RELKIND_RELATION)
597 elog(ERROR, "unexpected relkind: %d", (int) relkind);
598
599 relkind = RELKIND_PARTITIONED_TABLE;
600 partitioned = true;
601 }
602 else
603 partitioned = false;
604
605 /*
606 * Look up the namespace in which we are supposed to create the relation,
607 * check we have permission to create there, lock it against concurrent
608 * drop, and mark stmt->relation as RELPERSISTENCE_TEMP if a temporary
609 * namespace is selected.
610 */
611 namespaceId =
612 RangeVarGetAndCheckCreationNamespace(stmt->relation, NoLock, NULL);
613
614 /*
615 * Security check: disallow creating temp tables from security-restricted
616 * code. This is needed because calling code might not expect untrusted
617 * tables to appear in pg_temp at the front of its search path.
618 */
619 if (stmt->relation->relpersistence == RELPERSISTENCE_TEMP
620 && InSecurityRestrictedOperation())
621 ereport(ERROR,
622 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
623 errmsg("cannot create temporary table within security-restricted operation")));
624
625 /*
626 * Determine the lockmode to use when scanning parents. A self-exclusive
627 * lock is needed here.
628 *
629 * For regular inheritance, if two backends attempt to add children to the
630 * same parent simultaneously, and that parent has no pre-existing
631 * children, then both will attempt to update the parent's relhassubclass
632 * field, leading to a "tuple concurrently updated" error. Also, this
633 * interlocks against a concurrent ANALYZE on the parent table, which
634 * might otherwise be attempting to clear the parent's relhassubclass
635 * field, if its previous children were recently dropped.
636 *
637 * If the child table is a partition, then we instead grab an exclusive
638 * lock on the parent because its partition descriptor will be changed by
639 * addition of the new partition.
640 */
641 parentLockmode = (stmt->partbound != NULL ? AccessExclusiveLock :
642 ShareUpdateExclusiveLock);
643
644 /* Determine the list of OIDs of the parents. */
645 inheritOids = NIL;
646 foreach(listptr, stmt->inhRelations)
647 {
648 RangeVar *rv = (RangeVar *) lfirst(listptr);
649 Oid parentOid;
650
651 parentOid = RangeVarGetRelid(rv, parentLockmode, false);
652
653 /*
654 * Reject duplications in the list of parents.
655 */
656 if (list_member_oid(inheritOids, parentOid))
657 ereport(ERROR,
658 (errcode(ERRCODE_DUPLICATE_TABLE),
659 errmsg("relation \"%s\" would be inherited from more than once",
660 get_rel_name(parentOid))));
661
662 inheritOids = lappend_oid(inheritOids, parentOid);
663 }
664
665 /*
666 * Select tablespace to use: an explicitly indicated one, or (in the case
667 * of a partitioned table) the parent's, if it has one.
668 */
669 if (stmt->tablespacename)
670 {
671 tablespaceId = get_tablespace_oid(stmt->tablespacename, false);
672
673 if (partitioned && tablespaceId == MyDatabaseTableSpace)
674 ereport(ERROR,
675 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
676 errmsg("cannot specify default tablespace for partitioned relations")));
677 }
678 else if (stmt->partbound)
679 {
680 /*
681 * For partitions, when no other tablespace is specified, we default
682 * the tablespace to the parent partitioned table's.
683 */
684 Assert(list_length(inheritOids) == 1);
685 tablespaceId = get_rel_tablespace(linitial_oid(inheritOids));
686 }
687 else
688 tablespaceId = InvalidOid;
689
690 /* still nothing? use the default */
691 if (!OidIsValid(tablespaceId))
692 tablespaceId = GetDefaultTablespace(stmt->relation->relpersistence,
693 partitioned);
694
695 /* Check permissions except when using database's default */
696 if (OidIsValid(tablespaceId) && tablespaceId != MyDatabaseTableSpace)
697 {
698 AclResult aclresult;
699
700 aclresult = pg_tablespace_aclcheck(tablespaceId, GetUserId(),
701 ACL_CREATE);
702 if (aclresult != ACLCHECK_OK)
703 aclcheck_error(aclresult, OBJECT_TABLESPACE,
704 get_tablespace_name(tablespaceId));
705 }
706
707 /* In all cases disallow placing user relations in pg_global */
708 if (tablespaceId == GLOBALTABLESPACE_OID)
709 ereport(ERROR,
710 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
711 errmsg("only shared relations can be placed in pg_global tablespace")));
712
713 /* Identify user ID that will own the table */
714 if (!OidIsValid(ownerId))
715 ownerId = GetUserId();
716
717 /*
718 * Parse and validate reloptions, if any.
719 */
720 reloptions = transformRelOptions((Datum) 0, stmt->options, NULL, validnsps,
721 true, false);
722
723 if (relkind == RELKIND_VIEW)
724 (void) view_reloptions(reloptions, true);
725 else
726 (void) heap_reloptions(relkind, reloptions, true);
727
728 if (stmt->ofTypename)
729 {
730 AclResult aclresult;
731
732 ofTypeId = typenameTypeId(NULL, stmt->ofTypename);
733
734 aclresult = pg_type_aclcheck(ofTypeId, GetUserId(), ACL_USAGE);
735 if (aclresult != ACLCHECK_OK)
736 aclcheck_error_type(aclresult, ofTypeId);
737 }
738 else
739 ofTypeId = InvalidOid;
740
741 /*
742 * Look up inheritance ancestors and generate relation schema, including
743 * inherited attributes. (Note that stmt->tableElts is destructively
744 * modified by MergeAttributes.)
745 */
746 stmt->tableElts =
747 MergeAttributes(stmt->tableElts, inheritOids,
748 stmt->relation->relpersistence,
749 stmt->partbound != NULL,
750 &old_constraints);
751
752 /*
753 * Create a tuple descriptor from the relation schema. Note that this
754 * deals with column names, types, and NOT NULL constraints, but not
755 * default values or CHECK constraints; we handle those below.
756 */
757 descriptor = BuildDescForRelation(stmt->tableElts);
758
759 /*
760 * Find columns with default values and prepare for insertion of the
761 * defaults. Pre-cooked (that is, inherited) defaults go into a list of
762 * CookedConstraint structs that we'll pass to heap_create_with_catalog,
763 * while raw defaults go into a list of RawColumnDefault structs that will
764 * be processed by AddRelationNewConstraints. (We can't deal with raw
765 * expressions until we can do transformExpr.)
766 *
767 * We can set the atthasdef flags now in the tuple descriptor; this just
768 * saves StoreAttrDefault from having to do an immediate update of the
769 * pg_attribute rows.
770 */
771 rawDefaults = NIL;
772 cookedDefaults = NIL;
773 attnum = 0;
774
775 foreach(listptr, stmt->tableElts)
776 {
777 ColumnDef *colDef = lfirst(listptr);
778 Form_pg_attribute attr;
779
780 attnum++;
781 attr = TupleDescAttr(descriptor, attnum - 1);
782
783 if (colDef->raw_default != NULL)
784 {
785 RawColumnDefault *rawEnt;
786
787 Assert(colDef->cooked_default == NULL);
788
789 rawEnt = (RawColumnDefault *) palloc(sizeof(RawColumnDefault));
790 rawEnt->attnum = attnum;
791 rawEnt->raw_default = colDef->raw_default;
792 rawEnt->missingMode = false;
793 rawEnt->generated = colDef->generated;
794 rawDefaults = lappend(rawDefaults, rawEnt);
795 attr->atthasdef = true;
796 }
797 else if (colDef->cooked_default != NULL)
798 {
799 CookedConstraint *cooked;
800
801 cooked = (CookedConstraint *) palloc(sizeof(CookedConstraint));
802 cooked->contype = CONSTR_DEFAULT;
803 cooked->conoid = InvalidOid; /* until created */
804 cooked->name = NULL;
805 cooked->attnum = attnum;
806 cooked->expr = colDef->cooked_default;
807 cooked->skip_validation = false;
808 cooked->is_local = true; /* not used for defaults */
809 cooked->inhcount = 0; /* ditto */
810 cooked->is_no_inherit = false;
811 cookedDefaults = lappend(cookedDefaults, cooked);
812 attr->atthasdef = true;
813 }
814
815 if (colDef->identity)
816 attr->attidentity = colDef->identity;
817
818 if (colDef->generated)
819 attr->attgenerated = colDef->generated;
820 }
821
822 /*
823 * If the statement hasn't specified an access method, but we're defining
824 * a type of relation that needs one, use the default.
825 */
826 if (stmt->accessMethod != NULL)
827 {
828 accessMethod = stmt->accessMethod;
829
830 if (partitioned)
831 ereport(ERROR,
832 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
833 errmsg("specifying a table access method is not supported on a partitioned table")));
834
835 }
836 else if (relkind == RELKIND_RELATION ||
837 relkind == RELKIND_TOASTVALUE ||
838 relkind == RELKIND_MATVIEW)
839 accessMethod = default_table_access_method;
840
841 /* look up the access method, verify it is for a table */
842 if (accessMethod != NULL)
843 accessMethodId = get_table_am_oid(accessMethod, false);
844
845 /*
846 * Create the relation. Inherited defaults and constraints are passed in
847 * for immediate handling --- since they don't need parsing, they can be
848 * stored immediately.
849 */
850 relationId = heap_create_with_catalog(relname,
851 namespaceId,
852 tablespaceId,
853 InvalidOid,
854 InvalidOid,
855 ofTypeId,
856 ownerId,
857 accessMethodId,
858 descriptor,
859 list_concat(cookedDefaults,
860 old_constraints),
861 relkind,
862 stmt->relation->relpersistence,
863 false,
864 false,
865 stmt->oncommit,
866 reloptions,
867 true,
868 allowSystemTableMods,
869 false,
870 InvalidOid,
871 typaddress);
872
873 /*
874 * We must bump the command counter to make the newly-created relation
875 * tuple visible for opening.
876 */
877 CommandCounterIncrement();
878
879 /*
880 * Open the new relation and acquire exclusive lock on it. This isn't
881 * really necessary for locking out other backends (since they can't see
882 * the new rel anyway until we commit), but it keeps the lock manager from
883 * complaining about deadlock risks.
884 */
885 rel = relation_open(relationId, AccessExclusiveLock);
886
887 /*
888 * Now add any newly specified column default and generation expressions
889 * to the new relation. These are passed to us in the form of raw
890 * parsetrees; we need to transform them to executable expression trees
891 * before they can be added. The most convenient way to do that is to
892 * apply the parser's transformExpr routine, but transformExpr doesn't
893 * work unless we have a pre-existing relation. So, the transformation has
894 * to be postponed to this final step of CREATE TABLE.
895 *
896 * This needs to be before processing the partitioning clauses because
897 * those could refer to generated columns.
898 */
899 if (rawDefaults)
900 AddRelationNewConstraints(rel, rawDefaults, NIL,
901 true, true, false, queryString);
902
903 /*
904 * Make column generation expressions visible for use by partitioning.
905 */
906 CommandCounterIncrement();
907
908 /* Process and store partition bound, if any. */
909 if (stmt->partbound)
910 {
911 PartitionBoundSpec *bound;
912 ParseState *pstate;
913 Oid parentId = linitial_oid(inheritOids),
914 defaultPartOid;
915 Relation parent,
916 defaultRel = NULL;
917 RangeTblEntry *rte;
918
919 /* Already have strong enough lock on the parent */
920 parent = table_open(parentId, NoLock);
921
922 /*
923 * We are going to try to validate the partition bound specification
924 * against the partition key of parentRel, so it better have one.
925 */
926 if (parent->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
927 ereport(ERROR,
928 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
929 errmsg("\"%s\" is not partitioned",
930 RelationGetRelationName(parent))));
931
932 /*
933 * The partition constraint of the default partition depends on the
934 * partition bounds of every other partition. It is possible that
935 * another backend might be about to execute a query on the default
936 * partition table, and that the query relies on previously cached
937 * default partition constraints. We must therefore take a table lock
938 * strong enough to prevent all queries on the default partition from
939 * proceeding until we commit and send out a shared-cache-inval notice
940 * that will make them update their index lists.
941 *
942 * Order of locking: The relation being added won't be visible to
943 * other backends until it is committed, hence here in
944 * DefineRelation() the order of locking the default partition and the
945 * relation being added does not matter. But at all other places we
946 * need to lock the default relation before we lock the relation being
947 * added or removed i.e. we should take the lock in same order at all
948 * the places such that lock parent, lock default partition and then
949 * lock the partition so as to avoid a deadlock.
950 */
951 defaultPartOid =
952 get_default_oid_from_partdesc(RelationGetPartitionDesc(parent));
953 if (OidIsValid(defaultPartOid))
954 defaultRel = table_open(defaultPartOid, AccessExclusiveLock);
955
956 /* Transform the bound values */
957 pstate = make_parsestate(NULL);
958 pstate->p_sourcetext = queryString;
959
960 /*
961 * Add an RTE containing this relation, so that transformExpr called
962 * on partition bound expressions is able to report errors using a
963 * proper context.
964 */
965 rte = addRangeTableEntryForRelation(pstate, rel, AccessShareLock,
966 NULL, false, false);
967 addRTEtoQuery(pstate, rte, false, true, true);
968 bound = transformPartitionBound(pstate, parent, stmt->partbound);
969
970 /*
971 * Check first that the new partition's bound is valid and does not
972 * overlap with any of existing partitions of the parent.
973 */
974 check_new_partition_bound(relname, parent, bound);
975
976 /*
977 * If the default partition exists, its partition constraints will
978 * change after the addition of this new partition such that it won't
979 * allow any row that qualifies for this new partition. So, check that
980 * the existing data in the default partition satisfies the constraint
981 * as it will exist after adding this partition.
982 */
983 if (OidIsValid(defaultPartOid))
984 {
985 check_default_partition_contents(parent, defaultRel, bound);
986 /* Keep the lock until commit. */
987 table_close(defaultRel, NoLock);
988 }
989
990 /* Update the pg_class entry. */
991 StorePartitionBound(rel, parent, bound);
992
993 table_close(parent, NoLock);
994 }
995
996 /* Store inheritance information for new rel. */
997 StoreCatalogInheritance(relationId, inheritOids, stmt->partbound != NULL);
998
999 /*
1000 * Process the partitioning specification (if any) and store the partition
1001 * key information into the catalog.
1002 */
1003 if (partitioned)
1004 {
1005 ParseState *pstate;
1006 char strategy;
1007 int partnatts;
1008 AttrNumber partattrs[PARTITION_MAX_KEYS];
1009 Oid partopclass[PARTITION_MAX_KEYS];
1010 Oid partcollation[PARTITION_MAX_KEYS];
1011 List *partexprs = NIL;
1012
1013 pstate = make_parsestate(NULL);
1014 pstate->p_sourcetext = queryString;
1015
1016 partnatts = list_length(stmt->partspec->partParams);
1017
1018 /* Protect fixed-size arrays here and in executor */
1019 if (partnatts > PARTITION_MAX_KEYS)
1020 ereport(ERROR,
1021 (errcode(ERRCODE_TOO_MANY_COLUMNS),
1022 errmsg("cannot partition using more than %d columns",
1023 PARTITION_MAX_KEYS)));
1024
1025 /*
1026 * We need to transform the raw parsetrees corresponding to partition
1027 * expressions into executable expression trees. Like column defaults
1028 * and CHECK constraints, we could not have done the transformation
1029 * earlier.
1030 */
1031 stmt->partspec = transformPartitionSpec(rel, stmt->partspec,
1032 &strategy);
1033
1034 ComputePartitionAttrs(pstate, rel, stmt->partspec->partParams,
1035 partattrs, &partexprs, partopclass,
1036 partcollation, strategy);
1037
1038 StorePartitionKey(rel, strategy, partnatts, partattrs, partexprs,
1039 partopclass, partcollation);
1040
1041 /* make it all visible */
1042 CommandCounterIncrement();
1043 }
1044
1045 /*
1046 * If we're creating a partition, create now all the indexes, triggers,
1047 * FKs defined in the parent.
1048 *
1049 * We can't do it earlier, because DefineIndex wants to know the partition
1050 * key which we just stored.
1051 */
1052 if (stmt->partbound)
1053 {
1054 Oid parentId = linitial_oid(inheritOids);
1055 Relation parent;
1056 List *idxlist;
1057 ListCell *cell;
1058
1059 /* Already have strong enough lock on the parent */
1060 parent = table_open(parentId, NoLock);
1061 idxlist = RelationGetIndexList(parent);
1062
1063 /*
1064 * For each index in the parent table, create one in the partition
1065 */
1066 foreach(cell, idxlist)
1067 {
1068 Relation idxRel = index_open(lfirst_oid(cell), AccessShareLock);
1069 AttrNumber *attmap;
1070 IndexStmt *idxstmt;
1071 Oid constraintOid;
1072
1073 if (rel->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
1074 {
1075 if (idxRel->rd_index->indisunique)
1076 ereport(ERROR,
1077 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
1078 errmsg("cannot create foreign partition of partitioned table \"%s\"",
1079 RelationGetRelationName(parent)),
1080 errdetail("Table \"%s\" contains indexes that are unique.",
1081 RelationGetRelationName(parent))));
1082 else
1083 {
1084 index_close(idxRel, AccessShareLock);
1085 continue;
1086 }
1087 }
1088
1089 attmap = convert_tuples_by_name_map(RelationGetDescr(rel),
1090 RelationGetDescr(parent),
1091 gettext_noop("could not convert row type"));
1092 idxstmt =
1093 generateClonedIndexStmt(NULL, idxRel,
1094 attmap, RelationGetDescr(rel)->natts,
1095 &constraintOid);
1096 DefineIndex(RelationGetRelid(rel),
1097 idxstmt,
1098 InvalidOid,
1099 RelationGetRelid(idxRel),
1100 constraintOid,
1101 false, false, false, false, false);
1102
1103 index_close(idxRel, AccessShareLock);
1104 }
1105
1106 list_free(idxlist);
1107
1108 /*
1109 * If there are any row-level triggers, clone them to the new
1110 * partition.
1111 */
1112 if (parent->trigdesc != NULL)
1113 CloneRowTriggersToPartition(parent, rel);
1114
1115 /*
1116 * And foreign keys too. Note that because we're freshly creating the
1117 * table, there is no need to verify these new constraints.
1118 */
1119 CloneForeignKeyConstraints(NULL, parent, rel);
1120
1121 table_close(parent, NoLock);
1122 }
1123
1124 /*
1125 * Now add any newly specified CHECK constraints to the new relation. Same
1126 * as for defaults above, but these need to come after partitioning is set
1127 * up.
1128 */
1129 if (stmt->constraints)
1130 AddRelationNewConstraints(rel, NIL, stmt->constraints,
1131 true, true, false, queryString);
1132
1133 ObjectAddressSet(address, RelationRelationId, relationId);
1134
1135 /*
1136 * Clean up. We keep lock on new relation (although it shouldn't be
1137 * visible to anyone else anyway, until commit).
1138 */
1139 relation_close(rel, NoLock);
1140
1141 return address;
1142}
1143
1144/*
1145 * Emit the right error or warning message for a "DROP" command issued on a
1146 * non-existent relation
1147 */
1148static void
1149DropErrorMsgNonExistent(RangeVar *rel, char rightkind, bool missing_ok)
1150{
1151 const struct dropmsgstrings *rentry;
1152
1153 if (rel->schemaname != NULL &&
1154 !OidIsValid(LookupNamespaceNoError(rel->schemaname)))
1155 {
1156 if (!missing_ok)
1157 {
1158 ereport(ERROR,
1159 (errcode(ERRCODE_UNDEFINED_SCHEMA),
1160 errmsg("schema \"%s\" does not exist", rel->schemaname)));
1161 }
1162 else
1163 {
1164 ereport(NOTICE,
1165 (errmsg("schema \"%s\" does not exist, skipping",
1166 rel->schemaname)));
1167 }
1168 return;
1169 }
1170
1171 for (rentry = dropmsgstringarray; rentry->kind != '\0'; rentry++)
1172 {
1173 if (rentry->kind == rightkind)
1174 {
1175 if (!missing_ok)
1176 {
1177 ereport(ERROR,
1178 (errcode(rentry->nonexistent_code),
1179 errmsg(rentry->nonexistent_msg, rel->relname)));
1180 }
1181 else
1182 {
1183 ereport(NOTICE, (errmsg(rentry->skipping_msg, rel->relname)));
1184 break;
1185 }
1186 }
1187 }
1188
1189 Assert(rentry->kind != '\0'); /* Should be impossible */
1190}
1191
1192/*
1193 * Emit the right error message for a "DROP" command issued on a
1194 * relation of the wrong type
1195 */
1196static void
1197DropErrorMsgWrongType(const char *relname, char wrongkind, char rightkind)
1198{
1199 const struct dropmsgstrings *rentry;
1200 const struct dropmsgstrings *wentry;
1201
1202 for (rentry = dropmsgstringarray; rentry->kind != '\0'; rentry++)
1203 if (rentry->kind == rightkind)
1204 break;
1205 Assert(rentry->kind != '\0');
1206
1207 for (wentry = dropmsgstringarray; wentry->kind != '\0'; wentry++)
1208 if (wentry->kind == wrongkind)
1209 break;
1210 /* wrongkind could be something we don't have in our table... */
1211
1212 ereport(ERROR,
1213 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
1214 errmsg(rentry->nota_msg, relname),
1215 (wentry->kind != '\0') ? errhint("%s", _(wentry->drophint_msg)) : 0));
1216}
1217
1218/*
1219 * RemoveRelations
1220 * Implements DROP TABLE, DROP INDEX, DROP SEQUENCE, DROP VIEW,
1221 * DROP MATERIALIZED VIEW, DROP FOREIGN TABLE
1222 */
1223void
1224RemoveRelations(DropStmt *drop)
1225{
1226 ObjectAddresses *objects;
1227 char relkind;
1228 ListCell *cell;
1229 int flags = 0;
1230 LOCKMODE lockmode = AccessExclusiveLock;
1231
1232 /* DROP CONCURRENTLY uses a weaker lock, and has some restrictions */
1233 if (drop->concurrent)
1234 {
1235 flags |= PERFORM_DELETION_CONCURRENTLY;
1236 lockmode = ShareUpdateExclusiveLock;
1237 Assert(drop->removeType == OBJECT_INDEX);
1238 if (list_length(drop->objects) != 1)
1239 ereport(ERROR,
1240 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1241 errmsg("DROP INDEX CONCURRENTLY does not support dropping multiple objects")));
1242 if (drop->behavior == DROP_CASCADE)
1243 ereport(ERROR,
1244 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1245 errmsg("DROP INDEX CONCURRENTLY does not support CASCADE")));
1246 }
1247
1248 /*
1249 * First we identify all the relations, then we delete them in a single
1250 * performMultipleDeletions() call. This is to avoid unwanted DROP
1251 * RESTRICT errors if one of the relations depends on another.
1252 */
1253
1254 /* Determine required relkind */
1255 switch (drop->removeType)
1256 {
1257 case OBJECT_TABLE:
1258 relkind = RELKIND_RELATION;
1259 break;
1260
1261 case OBJECT_INDEX:
1262 relkind = RELKIND_INDEX;
1263 break;
1264
1265 case OBJECT_SEQUENCE:
1266 relkind = RELKIND_SEQUENCE;
1267 break;
1268
1269 case OBJECT_VIEW:
1270 relkind = RELKIND_VIEW;
1271 break;
1272
1273 case OBJECT_MATVIEW:
1274 relkind = RELKIND_MATVIEW;
1275 break;
1276
1277 case OBJECT_FOREIGN_TABLE:
1278 relkind = RELKIND_FOREIGN_TABLE;
1279 break;
1280
1281 default:
1282 elog(ERROR, "unrecognized drop object type: %d",
1283 (int) drop->removeType);
1284 relkind = 0; /* keep compiler quiet */
1285 break;
1286 }
1287
1288 /* Lock and validate each relation; build a list of object addresses */
1289 objects = new_object_addresses();
1290
1291 foreach(cell, drop->objects)
1292 {
1293 RangeVar *rel = makeRangeVarFromNameList((List *) lfirst(cell));
1294 Oid relOid;
1295 ObjectAddress obj;
1296 struct DropRelationCallbackState state;
1297
1298 /*
1299 * These next few steps are a great deal like relation_openrv, but we
1300 * don't bother building a relcache entry since we don't need it.
1301 *
1302 * Check for shared-cache-inval messages before trying to access the
1303 * relation. This is needed to cover the case where the name
1304 * identifies a rel that has been dropped and recreated since the
1305 * start of our transaction: if we don't flush the old syscache entry,
1306 * then we'll latch onto that entry and suffer an error later.
1307 */
1308 AcceptInvalidationMessages();
1309
1310 /* Look up the appropriate relation using namespace search. */
1311 state.relkind = relkind;
1312 state.heapOid = InvalidOid;
1313 state.partParentOid = InvalidOid;
1314 state.concurrent = drop->concurrent;
1315 relOid = RangeVarGetRelidExtended(rel, lockmode, RVR_MISSING_OK,
1316 RangeVarCallbackForDropRelation,
1317 (void *) &state);
1318
1319 /* Not there? */
1320 if (!OidIsValid(relOid))
1321 {
1322 DropErrorMsgNonExistent(rel, relkind, drop->missing_ok);
1323 continue;
1324 }
1325
1326 /* OK, we're ready to delete this one */
1327 obj.classId = RelationRelationId;
1328 obj.objectId = relOid;
1329 obj.objectSubId = 0;
1330
1331 add_exact_object_address(&obj, objects);
1332 }
1333
1334 performMultipleDeletions(objects, drop->behavior, flags);
1335
1336 free_object_addresses(objects);
1337}
1338
1339/*
1340 * Before acquiring a table lock, check whether we have sufficient rights.
1341 * In the case of DROP INDEX, also try to lock the table before the index.
1342 * Also, if the table to be dropped is a partition, we try to lock the parent
1343 * first.
1344 */
1345static void
1346RangeVarCallbackForDropRelation(const RangeVar *rel, Oid relOid, Oid oldRelOid,
1347 void *arg)
1348{
1349 HeapTuple tuple;
1350 struct DropRelationCallbackState *state;
1351 char relkind;
1352 char expected_relkind;
1353 bool is_partition;
1354 Form_pg_class classform;
1355 LOCKMODE heap_lockmode;
1356 bool invalid_system_index = false;
1357
1358 state = (struct DropRelationCallbackState *) arg;
1359 relkind = state->relkind;
1360 heap_lockmode = state->concurrent ?
1361 ShareUpdateExclusiveLock : AccessExclusiveLock;
1362
1363 /*
1364 * If we previously locked some other index's heap, and the name we're
1365 * looking up no longer refers to that relation, release the now-useless
1366 * lock.
1367 */
1368 if (relOid != oldRelOid && OidIsValid(state->heapOid))
1369 {
1370 UnlockRelationOid(state->heapOid, heap_lockmode);
1371 state->heapOid = InvalidOid;
1372 }
1373
1374 /*
1375 * Similarly, if we previously locked some other partition's heap, and the
1376 * name we're looking up no longer refers to that relation, release the
1377 * now-useless lock.
1378 */
1379 if (relOid != oldRelOid && OidIsValid(state->partParentOid))
1380 {
1381 UnlockRelationOid(state->partParentOid, AccessExclusiveLock);
1382 state->partParentOid = InvalidOid;
1383 }
1384
1385 /* Didn't find a relation, so no need for locking or permission checks. */
1386 if (!OidIsValid(relOid))
1387 return;
1388
1389 tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relOid));
1390 if (!HeapTupleIsValid(tuple))
1391 return; /* concurrently dropped, so nothing to do */
1392 classform = (Form_pg_class) GETSTRUCT(tuple);
1393 is_partition = classform->relispartition;
1394
1395 /*
1396 * Both RELKIND_RELATION and RELKIND_PARTITIONED_TABLE are OBJECT_TABLE,
1397 * but RemoveRelations() can only pass one relkind for a given relation.
1398 * It chooses RELKIND_RELATION for both regular and partitioned tables.
1399 * That means we must be careful before giving the wrong type error when
1400 * the relation is RELKIND_PARTITIONED_TABLE. An equivalent problem
1401 * exists with indexes.
1402 */
1403 if (classform->relkind == RELKIND_PARTITIONED_TABLE)
1404 expected_relkind = RELKIND_RELATION;
1405 else if (classform->relkind == RELKIND_PARTITIONED_INDEX)
1406 expected_relkind = RELKIND_INDEX;
1407 else
1408 expected_relkind = classform->relkind;
1409
1410 if (relkind != expected_relkind)
1411 DropErrorMsgWrongType(rel->relname, classform->relkind, relkind);
1412
1413 /* Allow DROP to either table owner or schema owner */
1414 if (!pg_class_ownercheck(relOid, GetUserId()) &&
1415 !pg_namespace_ownercheck(classform->relnamespace, GetUserId()))
1416 aclcheck_error(ACLCHECK_NOT_OWNER, get_relkind_objtype(get_rel_relkind(relOid)),
1417 rel->relname);
1418
1419 /*
1420 * Check the case of a system index that might have been invalidated by a
1421 * failed concurrent process and allow its drop. For the time being, this
1422 * only concerns indexes of toast relations that became invalid during a
1423 * REINDEX CONCURRENTLY process.
1424 */
1425 if (IsSystemClass(relOid, classform) && relkind == RELKIND_INDEX)
1426 {
1427 HeapTuple locTuple;
1428 Form_pg_index indexform;
1429 bool indisvalid;
1430
1431 locTuple = SearchSysCache1(INDEXRELID, ObjectIdGetDatum(relOid));
1432 if (!HeapTupleIsValid(locTuple))
1433 {
1434 ReleaseSysCache(tuple);
1435 return;
1436 }
1437
1438 indexform = (Form_pg_index) GETSTRUCT(locTuple);
1439 indisvalid = indexform->indisvalid;
1440 ReleaseSysCache(locTuple);
1441
1442 /* Mark object as being an invalid index of system catalogs */
1443 if (!indisvalid)
1444 invalid_system_index = true;
1445 }
1446
1447 /* In the case of an invalid index, it is fine to bypass this check */
1448 if (!invalid_system_index && !allowSystemTableMods && IsSystemClass(relOid, classform))
1449 ereport(ERROR,
1450 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
1451 errmsg("permission denied: \"%s\" is a system catalog",
1452 rel->relname)));
1453
1454 ReleaseSysCache(tuple);
1455
1456 /*
1457 * In DROP INDEX, attempt to acquire lock on the parent table before
1458 * locking the index. index_drop() will need this anyway, and since
1459 * regular queries lock tables before their indexes, we risk deadlock if
1460 * we do it the other way around. No error if we don't find a pg_index
1461 * entry, though --- the relation may have been dropped.
1462 */
1463 if ((relkind == RELKIND_INDEX || relkind == RELKIND_PARTITIONED_INDEX) &&
1464 relOid != oldRelOid)
1465 {
1466 state->heapOid = IndexGetRelation(relOid, true);
1467 if (OidIsValid(state->heapOid))
1468 LockRelationOid(state->heapOid, heap_lockmode);
1469 }
1470
1471 /*
1472 * Similarly, if the relation is a partition, we must acquire lock on its
1473 * parent before locking the partition. That's because queries lock the
1474 * parent before its partitions, so we risk deadlock it we do it the other
1475 * way around.
1476 */
1477 if (is_partition && relOid != oldRelOid)
1478 {
1479 state->partParentOid = get_partition_parent(relOid);
1480 if (OidIsValid(state->partParentOid))
1481 LockRelationOid(state->partParentOid, AccessExclusiveLock);
1482 }
1483}
1484
1485/*
1486 * ExecuteTruncate
1487 * Executes a TRUNCATE command.
1488 *
1489 * This is a multi-relation truncate. We first open and grab exclusive
1490 * lock on all relations involved, checking permissions and otherwise
1491 * verifying that the relation is OK for truncation. In CASCADE mode,
1492 * relations having FK references to the targeted relations are automatically
1493 * added to the group; in RESTRICT mode, we check that all FK references are
1494 * internal to the group that's being truncated. Finally all the relations
1495 * are truncated and reindexed.
1496 */
1497void
1498ExecuteTruncate(TruncateStmt *stmt)
1499{
1500 List *rels = NIL;
1501 List *relids = NIL;
1502 List *relids_logged = NIL;
1503 ListCell *cell;
1504
1505 /*
1506 * Open, exclusive-lock, and check all the explicitly-specified relations
1507 */
1508 foreach(cell, stmt->relations)
1509 {
1510 RangeVar *rv = lfirst(cell);
1511 Relation rel;
1512 bool recurse = rv->inh;
1513 Oid myrelid;
1514 LOCKMODE lockmode = AccessExclusiveLock;
1515
1516 myrelid = RangeVarGetRelidExtended(rv, lockmode,
1517 0, RangeVarCallbackForTruncate,
1518 NULL);
1519
1520 /* open the relation, we already hold a lock on it */
1521 rel = table_open(myrelid, NoLock);
1522
1523 /* don't throw error for "TRUNCATE foo, foo" */
1524 if (list_member_oid(relids, myrelid))
1525 {
1526 table_close(rel, lockmode);
1527 continue;
1528 }
1529
1530 /*
1531 * RangeVarGetRelidExtended() has done most checks with its callback,
1532 * but other checks with the now-opened Relation remain.
1533 */
1534 truncate_check_activity(rel);
1535
1536 rels = lappend(rels, rel);
1537 relids = lappend_oid(relids, myrelid);
1538 /* Log this relation only if needed for logical decoding */
1539 if (RelationIsLogicallyLogged(rel))
1540 relids_logged = lappend_oid(relids_logged, myrelid);
1541
1542 if (recurse)
1543 {
1544 ListCell *child;
1545 List *children;
1546
1547 children = find_all_inheritors(myrelid, lockmode, NULL);
1548
1549 foreach(child, children)
1550 {
1551 Oid childrelid = lfirst_oid(child);
1552
1553 if (list_member_oid(relids, childrelid))
1554 continue;
1555
1556 /* find_all_inheritors already got lock */
1557 rel = table_open(childrelid, NoLock);
1558
1559 /*
1560 * It is possible that the parent table has children that are
1561 * temp tables of other backends. We cannot safely access
1562 * such tables (because of buffering issues), and the best
1563 * thing to do is to silently ignore them. Note that this
1564 * check is the same as one of the checks done in
1565 * truncate_check_activity() called below, still it is kept
1566 * here for simplicity.
1567 */
1568 if (RELATION_IS_OTHER_TEMP(rel))
1569 {
1570 table_close(rel, lockmode);
1571 continue;
1572 }
1573
1574 truncate_check_rel(RelationGetRelid(rel), rel->rd_rel);
1575 truncate_check_activity(rel);
1576
1577 rels = lappend(rels, rel);
1578 relids = lappend_oid(relids, childrelid);
1579 /* Log this relation only if needed for logical decoding */
1580 if (RelationIsLogicallyLogged(rel))
1581 relids_logged = lappend_oid(relids_logged, childrelid);
1582 }
1583 }
1584 else if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
1585 ereport(ERROR,
1586 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
1587 errmsg("cannot truncate only a partitioned table"),
1588 errhint("Do not specify the ONLY keyword, or use TRUNCATE ONLY on the partitions directly.")));
1589 }
1590
1591 ExecuteTruncateGuts(rels, relids, relids_logged,
1592 stmt->behavior, stmt->restart_seqs);
1593
1594 /* And close the rels */
1595 foreach(cell, rels)
1596 {
1597 Relation rel = (Relation) lfirst(cell);
1598
1599 table_close(rel, NoLock);
1600 }
1601}
1602
1603/*
1604 * ExecuteTruncateGuts
1605 *
1606 * Internal implementation of TRUNCATE. This is called by the actual TRUNCATE
1607 * command (see above) as well as replication subscribers that execute a
1608 * replicated TRUNCATE action.
1609 *
1610 * explicit_rels is the list of Relations to truncate that the command
1611 * specified. relids is the list of Oids corresponding to explicit_rels.
1612 * relids_logged is the list of Oids (a subset of relids) that require
1613 * WAL-logging. This is all a bit redundant, but the existing callers have
1614 * this information handy in this form.
1615 */
1616void
1617ExecuteTruncateGuts(List *explicit_rels, List *relids, List *relids_logged,
1618 DropBehavior behavior, bool restart_seqs)
1619{
1620 List *rels;
1621 List *seq_relids = NIL;
1622 EState *estate;
1623 ResultRelInfo *resultRelInfos;
1624 ResultRelInfo *resultRelInfo;
1625 SubTransactionId mySubid;
1626 ListCell *cell;
1627 Oid *logrelids;
1628
1629 /*
1630 * Check the explicitly-specified relations.
1631 *
1632 * In CASCADE mode, suck in all referencing relations as well. This
1633 * requires multiple iterations to find indirectly-dependent relations. At
1634 * each phase, we need to exclusive-lock new rels before looking for their
1635 * dependencies, else we might miss something. Also, we check each rel as
1636 * soon as we open it, to avoid a faux pas such as holding lock for a long
1637 * time on a rel we have no permissions for.
1638 */
1639 rels = list_copy(explicit_rels);
1640 if (behavior == DROP_CASCADE)
1641 {
1642 for (;;)
1643 {
1644 List *newrelids;
1645
1646 newrelids = heap_truncate_find_FKs(relids);
1647 if (newrelids == NIL)
1648 break; /* nothing else to add */
1649
1650 foreach(cell, newrelids)
1651 {
1652 Oid relid = lfirst_oid(cell);
1653 Relation rel;
1654
1655 rel = table_open(relid, AccessExclusiveLock);
1656 ereport(NOTICE,
1657 (errmsg("truncate cascades to table \"%s\"",
1658 RelationGetRelationName(rel))));
1659 truncate_check_rel(relid, rel->rd_rel);
1660 truncate_check_activity(rel);
1661 rels = lappend(rels, rel);
1662 relids = lappend_oid(relids, relid);
1663 /* Log this relation only if needed for logical decoding */
1664 if (RelationIsLogicallyLogged(rel))
1665 relids_logged = lappend_oid(relids_logged, relid);
1666 }
1667 }
1668 }
1669
1670 /*
1671 * Check foreign key references. In CASCADE mode, this should be
1672 * unnecessary since we just pulled in all the references; but as a
1673 * cross-check, do it anyway if in an Assert-enabled build.
1674 */
1675#ifdef USE_ASSERT_CHECKING
1676 heap_truncate_check_FKs(rels, false);
1677#else
1678 if (behavior == DROP_RESTRICT)
1679 heap_truncate_check_FKs(rels, false);
1680#endif
1681
1682 /*
1683 * If we are asked to restart sequences, find all the sequences, lock them
1684 * (we need AccessExclusiveLock for ResetSequence), and check permissions.
1685 * We want to do this early since it's pointless to do all the truncation
1686 * work only to fail on sequence permissions.
1687 */
1688 if (restart_seqs)
1689 {
1690 foreach(cell, rels)
1691 {
1692 Relation rel = (Relation) lfirst(cell);
1693 List *seqlist = getOwnedSequences(RelationGetRelid(rel), 0);
1694 ListCell *seqcell;
1695
1696 foreach(seqcell, seqlist)
1697 {
1698 Oid seq_relid = lfirst_oid(seqcell);
1699 Relation seq_rel;
1700
1701 seq_rel = relation_open(seq_relid, AccessExclusiveLock);
1702
1703 /* This check must match AlterSequence! */
1704 if (!pg_class_ownercheck(seq_relid, GetUserId()))
1705 aclcheck_error(ACLCHECK_NOT_OWNER, OBJECT_SEQUENCE,
1706 RelationGetRelationName(seq_rel));
1707
1708 seq_relids = lappend_oid(seq_relids, seq_relid);
1709
1710 relation_close(seq_rel, NoLock);
1711 }
1712 }
1713 }
1714
1715 /* Prepare to catch AFTER triggers. */
1716 AfterTriggerBeginQuery();
1717
1718 /*
1719 * To fire triggers, we'll need an EState as well as a ResultRelInfo for
1720 * each relation. We don't need to call ExecOpenIndices, though.
1721 */
1722 estate = CreateExecutorState();
1723 resultRelInfos = (ResultRelInfo *)
1724 palloc(list_length(rels) * sizeof(ResultRelInfo));
1725 resultRelInfo = resultRelInfos;
1726 foreach(cell, rels)
1727 {
1728 Relation rel = (Relation) lfirst(cell);
1729
1730 InitResultRelInfo(resultRelInfo,
1731 rel,
1732 0, /* dummy rangetable index */
1733 NULL,
1734 0);
1735 resultRelInfo++;
1736 }
1737 estate->es_result_relations = resultRelInfos;
1738 estate->es_num_result_relations = list_length(rels);
1739
1740 /*
1741 * Process all BEFORE STATEMENT TRUNCATE triggers before we begin
1742 * truncating (this is because one of them might throw an error). Also, if
1743 * we were to allow them to prevent statement execution, that would need
1744 * to be handled here.
1745 */
1746 resultRelInfo = resultRelInfos;
1747 foreach(cell, rels)
1748 {
1749 estate->es_result_relation_info = resultRelInfo;
1750 ExecBSTruncateTriggers(estate, resultRelInfo);
1751 resultRelInfo++;
1752 }
1753
1754 /*
1755 * OK, truncate each table.
1756 */
1757 mySubid = GetCurrentSubTransactionId();
1758
1759 foreach(cell, rels)
1760 {
1761 Relation rel = (Relation) lfirst(cell);
1762
1763 /* Skip partitioned tables as there is nothing to do */
1764 if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
1765 continue;
1766
1767 /*
1768 * Normally, we need a transaction-safe truncation here. However, if
1769 * the table was either created in the current (sub)transaction or has
1770 * a new relfilenode in the current (sub)transaction, then we can just
1771 * truncate it in-place, because a rollback would cause the whole
1772 * table or the current physical file to be thrown away anyway.
1773 */
1774 if (rel->rd_createSubid == mySubid ||
1775 rel->rd_newRelfilenodeSubid == mySubid)
1776 {
1777 /* Immediate, non-rollbackable truncation is OK */
1778 heap_truncate_one_rel(rel);
1779 }
1780 else
1781 {
1782 Oid heap_relid;
1783 Oid toast_relid;
1784
1785 /*
1786 * This effectively deletes all rows in the table, and may be done
1787 * in a serializable transaction. In that case we must record a
1788 * rw-conflict in to this transaction from each transaction
1789 * holding a predicate lock on the table.
1790 */
1791 CheckTableForSerializableConflictIn(rel);
1792
1793 /*
1794 * Need the full transaction-safe pushups.
1795 *
1796 * Create a new empty storage file for the relation, and assign it
1797 * as the relfilenode value. The old storage file is scheduled for
1798 * deletion at commit.
1799 */
1800 RelationSetNewRelfilenode(rel, rel->rd_rel->relpersistence);
1801
1802 heap_relid = RelationGetRelid(rel);
1803
1804 /*
1805 * The same for the toast table, if any.
1806 */
1807 toast_relid = rel->rd_rel->reltoastrelid;
1808 if (OidIsValid(toast_relid))
1809 {
1810 Relation toastrel = relation_open(toast_relid,
1811 AccessExclusiveLock);
1812
1813 RelationSetNewRelfilenode(toastrel,
1814 toastrel->rd_rel->relpersistence);
1815 table_close(toastrel, NoLock);
1816 }
1817
1818 /*
1819 * Reconstruct the indexes to match, and we're done.
1820 */
1821 reindex_relation(heap_relid, REINDEX_REL_PROCESS_TOAST, 0);
1822 }
1823
1824 pgstat_count_truncate(rel);
1825 }
1826
1827 /*
1828 * Restart owned sequences if we were asked to.
1829 */
1830 foreach(cell, seq_relids)
1831 {
1832 Oid seq_relid = lfirst_oid(cell);
1833
1834 ResetSequence(seq_relid);
1835 }
1836
1837 /*
1838 * Write a WAL record to allow this set of actions to be logically
1839 * decoded.
1840 *
1841 * Assemble an array of relids so we can write a single WAL record for the
1842 * whole action.
1843 */
1844 if (list_length(relids_logged) > 0)
1845 {
1846 xl_heap_truncate xlrec;
1847 int i = 0;
1848
1849 /* should only get here if wal_level >= logical */
1850 Assert(XLogLogicalInfoActive());
1851
1852 logrelids = palloc(list_length(relids_logged) * sizeof(Oid));
1853 foreach(cell, relids_logged)
1854 logrelids[i++] = lfirst_oid(cell);
1855
1856 xlrec.dbId = MyDatabaseId;
1857 xlrec.nrelids = list_length(relids_logged);
1858 xlrec.flags = 0;
1859 if (behavior == DROP_CASCADE)
1860 xlrec.flags |= XLH_TRUNCATE_CASCADE;
1861 if (restart_seqs)
1862 xlrec.flags |= XLH_TRUNCATE_RESTART_SEQS;
1863
1864 XLogBeginInsert();
1865 XLogRegisterData((char *) &xlrec, SizeOfHeapTruncate);
1866 XLogRegisterData((char *) logrelids, list_length(relids_logged) * sizeof(Oid));
1867
1868 XLogSetRecordFlags(XLOG_INCLUDE_ORIGIN);
1869
1870 (void) XLogInsert(RM_HEAP_ID, XLOG_HEAP_TRUNCATE);
1871 }
1872
1873 /*
1874 * Process all AFTER STATEMENT TRUNCATE triggers.
1875 */
1876 resultRelInfo = resultRelInfos;
1877 foreach(cell, rels)
1878 {
1879 estate->es_result_relation_info = resultRelInfo;
1880 ExecASTruncateTriggers(estate, resultRelInfo);
1881 resultRelInfo++;
1882 }
1883
1884 /* Handle queued AFTER triggers */
1885 AfterTriggerEndQuery(estate);
1886
1887 /* We can clean up the EState now */
1888 FreeExecutorState(estate);
1889
1890 /*
1891 * Close any rels opened by CASCADE (can't do this while EState still
1892 * holds refs)
1893 */
1894 rels = list_difference_ptr(rels, explicit_rels);
1895 foreach(cell, rels)
1896 {
1897 Relation rel = (Relation) lfirst(cell);
1898
1899 table_close(rel, NoLock);
1900 }
1901}
1902
1903/*
1904 * Check that a given relation is safe to truncate. Subroutine for
1905 * ExecuteTruncate() and RangeVarCallbackForTruncate().
1906 */
1907static void
1908truncate_check_rel(Oid relid, Form_pg_class reltuple)
1909{
1910 AclResult aclresult;
1911 char *relname = NameStr(reltuple->relname);
1912
1913 /*
1914 * Only allow truncate on regular tables and partitioned tables (although,
1915 * the latter are only being included here for the following checks; no
1916 * physical truncation will occur in their case.)
1917 */
1918 if (reltuple->relkind != RELKIND_RELATION &&
1919 reltuple->relkind != RELKIND_PARTITIONED_TABLE)
1920 ereport(ERROR,
1921 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
1922 errmsg("\"%s\" is not a table", relname)));
1923
1924 /* Permissions checks */
1925 aclresult = pg_class_aclcheck(relid, GetUserId(), ACL_TRUNCATE);
1926 if (aclresult != ACLCHECK_OK)
1927 aclcheck_error(aclresult, get_relkind_objtype(reltuple->relkind),
1928 relname);
1929
1930 if (!allowSystemTableMods && IsSystemClass(relid, reltuple))
1931 ereport(ERROR,
1932 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
1933 errmsg("permission denied: \"%s\" is a system catalog",
1934 relname)));
1935}
1936
1937/*
1938 * Set of extra sanity checks to check if a given relation is safe to
1939 * truncate. This is split with truncate_check_rel() as
1940 * RangeVarCallbackForTruncate() cannot open a Relation yet.
1941 */
1942static void
1943truncate_check_activity(Relation rel)
1944{
1945 /*
1946 * Don't allow truncate on temp tables of other backends ... their local
1947 * buffer manager is not going to cope.
1948 */
1949 if (RELATION_IS_OTHER_TEMP(rel))
1950 ereport(ERROR,
1951 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1952 errmsg("cannot truncate temporary tables of other sessions")));
1953
1954 /*
1955 * Also check for active uses of the relation in the current transaction,
1956 * including open scans and pending AFTER trigger events.
1957 */
1958 CheckTableNotInUse(rel, "TRUNCATE");
1959}
1960
1961/*
1962 * storage_name
1963 * returns the name corresponding to a typstorage/attstorage enum value
1964 */
1965static const char *
1966storage_name(char c)
1967{
1968 switch (c)
1969 {
1970 case 'p':
1971 return "PLAIN";
1972 case 'm':
1973 return "MAIN";
1974 case 'x':
1975 return "EXTENDED";
1976 case 'e':
1977 return "EXTERNAL";
1978 default:
1979 return "???";
1980 }
1981}
1982
1983/*----------
1984 * MergeAttributes
1985 * Returns new schema given initial schema and superclasses.
1986 *
1987 * Input arguments:
1988 * 'schema' is the column/attribute definition for the table. (It's a list
1989 * of ColumnDef's.) It is destructively changed.
1990 * 'supers' is a list of OIDs of parent relations, already locked by caller.
1991 * 'relpersistence' is a persistence type of the table.
1992 * 'is_partition' tells if the table is a partition
1993 *
1994 * Output arguments:
1995 * 'supconstr' receives a list of constraints belonging to the parents,
1996 * updated as necessary to be valid for the child.
1997 *
1998 * Return value:
1999 * Completed schema list.
2000 *
2001 * Notes:
2002 * The order in which the attributes are inherited is very important.
2003 * Intuitively, the inherited attributes should come first. If a table
2004 * inherits from multiple parents, the order of those attributes are
2005 * according to the order of the parents specified in CREATE TABLE.
2006 *
2007 * Here's an example:
2008 *
2009 * create table person (name text, age int4, location point);
2010 * create table emp (salary int4, manager text) inherits(person);
2011 * create table student (gpa float8) inherits (person);
2012 * create table stud_emp (percent int4) inherits (emp, student);
2013 *
2014 * The order of the attributes of stud_emp is:
2015 *
2016 * person {1:name, 2:age, 3:location}
2017 * / \
2018 * {6:gpa} student emp {4:salary, 5:manager}
2019 * \ /
2020 * stud_emp {7:percent}
2021 *
2022 * If the same attribute name appears multiple times, then it appears
2023 * in the result table in the proper location for its first appearance.
2024 *
2025 * Constraints (including NOT NULL constraints) for the child table
2026 * are the union of all relevant constraints, from both the child schema
2027 * and parent tables.
2028 *
2029 * The default value for a child column is defined as:
2030 * (1) If the child schema specifies a default, that value is used.
2031 * (2) If neither the child nor any parent specifies a default, then
2032 * the column will not have a default.
2033 * (3) If conflicting defaults are inherited from different parents
2034 * (and not overridden by the child), an error is raised.
2035 * (4) Otherwise the inherited default is used.
2036 * Rule (3) is new in Postgres 7.1; in earlier releases you got a
2037 * rather arbitrary choice of which parent default to use.
2038 *----------
2039 */
2040static List *
2041MergeAttributes(List *schema, List *supers, char relpersistence,
2042 bool is_partition, List **supconstr)
2043{
2044 ListCell *entry;
2045 List *inhSchema = NIL;
2046 List *constraints = NIL;
2047 bool have_bogus_defaults = false;
2048 int child_attno;
2049 static Node bogus_marker = {0}; /* marks conflicting defaults */
2050 List *saved_schema = NIL;
2051
2052 /*
2053 * Check for and reject tables with too many columns. We perform this
2054 * check relatively early for two reasons: (a) we don't run the risk of
2055 * overflowing an AttrNumber in subsequent code (b) an O(n^2) algorithm is
2056 * okay if we're processing <= 1600 columns, but could take minutes to
2057 * execute if the user attempts to create a table with hundreds of
2058 * thousands of columns.
2059 *
2060 * Note that we also need to check that we do not exceed this figure after
2061 * including columns from inherited relations.
2062 */
2063 if (list_length(schema) > MaxHeapAttributeNumber)
2064 ereport(ERROR,
2065 (errcode(ERRCODE_TOO_MANY_COLUMNS),
2066 errmsg("tables can have at most %d columns",
2067 MaxHeapAttributeNumber)));
2068
2069 /*
2070 * Check for duplicate names in the explicit list of attributes.
2071 *
2072 * Although we might consider merging such entries in the same way that we
2073 * handle name conflicts for inherited attributes, it seems to make more
2074 * sense to assume such conflicts are errors.
2075 */
2076 foreach(entry, schema)
2077 {
2078 ColumnDef *coldef = lfirst(entry);
2079 ListCell *rest = lnext(entry);
2080 ListCell *prev = entry;
2081
2082 if (!is_partition && coldef->typeName == NULL)
2083 {
2084 /*
2085 * Typed table column option that does not belong to a column from
2086 * the type. This works because the columns from the type come
2087 * first in the list. (We omit this check for partition column
2088 * lists; those are processed separately below.)
2089 */
2090 ereport(ERROR,
2091 (errcode(ERRCODE_UNDEFINED_COLUMN),
2092 errmsg("column \"%s\" does not exist",
2093 coldef->colname)));
2094 }
2095
2096 while (rest != NULL)
2097 {
2098 ColumnDef *restdef = lfirst(rest);
2099 ListCell *next = lnext(rest); /* need to save it in case we
2100 * delete it */
2101
2102 if (strcmp(coldef->colname, restdef->colname) == 0)
2103 {
2104 if (coldef->is_from_type)
2105 {
2106 /*
2107 * merge the column options into the column from the type
2108 */
2109 coldef->is_not_null = restdef->is_not_null;
2110 coldef->raw_default = restdef->raw_default;
2111 coldef->cooked_default = restdef->cooked_default;
2112 coldef->constraints = restdef->constraints;
2113 coldef->is_from_type = false;
2114 schema = list_delete_cell(schema, rest, prev);
2115
2116 /*
2117 * As two elements are merged and one is removed, we
2118 * should never finish with an empty list.
2119 */
2120 Assert(schema != NIL);
2121 }
2122 else
2123 ereport(ERROR,
2124 (errcode(ERRCODE_DUPLICATE_COLUMN),
2125 errmsg("column \"%s\" specified more than once",
2126 coldef->colname)));
2127 }
2128 prev = rest;
2129 rest = next;
2130 }
2131 }
2132
2133 /*
2134 * In case of a partition, there are no new column definitions, only dummy
2135 * ColumnDefs created for column constraints. Set them aside for now and
2136 * process them at the end.
2137 */
2138 if (is_partition)
2139 {
2140 saved_schema = schema;
2141 schema = NIL;
2142 }
2143
2144 /*
2145 * Scan the parents left-to-right, and merge their attributes to form a
2146 * list of inherited attributes (inhSchema). Also check to see if we need
2147 * to inherit an OID column.
2148 */
2149 child_attno = 0;
2150 foreach(entry, supers)
2151 {
2152 Oid parent = lfirst_oid(entry);
2153 Relation relation;
2154 TupleDesc tupleDesc;
2155 TupleConstr *constr;
2156 AttrNumber *newattno;
2157 AttrNumber parent_attno;
2158
2159 /* caller already got lock */
2160 relation = table_open(parent, NoLock);
2161
2162 /*
2163 * Check for active uses of the parent partitioned table in the
2164 * current transaction, such as being used in some manner by an
2165 * enclosing command.
2166 */
2167 if (is_partition)
2168 CheckTableNotInUse(relation, "CREATE TABLE .. PARTITION OF");
2169
2170 /*
2171 * We do not allow partitioned tables and partitions to participate in
2172 * regular inheritance.
2173 */
2174 if (relation->rd_rel->relkind == RELKIND_PARTITIONED_TABLE &&
2175 !is_partition)
2176 ereport(ERROR,
2177 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
2178 errmsg("cannot inherit from partitioned table \"%s\"",
2179 RelationGetRelationName(relation))));
2180 if (relation->rd_rel->relispartition && !is_partition)
2181 ereport(ERROR,
2182 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
2183 errmsg("cannot inherit from partition \"%s\"",
2184 RelationGetRelationName(relation))));
2185
2186 if (relation->rd_rel->relkind != RELKIND_RELATION &&
2187 relation->rd_rel->relkind != RELKIND_FOREIGN_TABLE &&
2188 relation->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
2189 ereport(ERROR,
2190 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
2191 errmsg("inherited relation \"%s\" is not a table or foreign table",
2192 RelationGetRelationName(relation))));
2193
2194 /*
2195 * If the parent is permanent, so must be all of its partitions. Note
2196 * that inheritance allows that case.
2197 */
2198 if (is_partition &&
2199 relation->rd_rel->relpersistence != RELPERSISTENCE_TEMP &&
2200 relpersistence == RELPERSISTENCE_TEMP)
2201 ereport(ERROR,
2202 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
2203 errmsg("cannot create a temporary relation as partition of permanent relation \"%s\"",
2204 RelationGetRelationName(relation))));
2205
2206 /* Permanent rels cannot inherit from temporary ones */
2207 if (relpersistence != RELPERSISTENCE_TEMP &&
2208 relation->rd_rel->relpersistence == RELPERSISTENCE_TEMP)
2209 ereport(ERROR,
2210 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
2211 errmsg(!is_partition
2212 ? "cannot inherit from temporary relation \"%s\""
2213 : "cannot create a permanent relation as partition of temporary relation \"%s\"",
2214 RelationGetRelationName(relation))));
2215
2216 /* If existing rel is temp, it must belong to this session */
2217 if (relation->rd_rel->relpersistence == RELPERSISTENCE_TEMP &&
2218 !relation->rd_islocaltemp)
2219 ereport(ERROR,
2220 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
2221 errmsg(!is_partition
2222 ? "cannot inherit from temporary relation of another session"
2223 : "cannot create as partition of temporary relation of another session")));
2224
2225 /*
2226 * We should have an UNDER permission flag for this, but for now,
2227 * demand that creator of a child table own the parent.
2228 */
2229 if (!pg_class_ownercheck(RelationGetRelid(relation), GetUserId()))
2230 aclcheck_error(ACLCHECK_NOT_OWNER, get_relkind_objtype(relation->rd_rel->relkind),
2231 RelationGetRelationName(relation));
2232
2233 tupleDesc = RelationGetDescr(relation);
2234 constr = tupleDesc->constr;
2235
2236 /*
2237 * newattno[] will contain the child-table attribute numbers for the
2238 * attributes of this parent table. (They are not the same for
2239 * parents after the first one, nor if we have dropped columns.)
2240 */
2241 newattno = (AttrNumber *)
2242 palloc0(tupleDesc->natts * sizeof(AttrNumber));
2243
2244 for (parent_attno = 1; parent_attno <= tupleDesc->natts;
2245 parent_attno++)
2246 {
2247 Form_pg_attribute attribute = TupleDescAttr(tupleDesc,
2248 parent_attno - 1);
2249 char *attributeName = NameStr(attribute->attname);
2250 int exist_attno;
2251 ColumnDef *def;
2252
2253 /*
2254 * Ignore dropped columns in the parent.
2255 */
2256 if (attribute->attisdropped)
2257 continue; /* leave newattno entry as zero */
2258
2259 /*
2260 * Does it conflict with some previously inherited column?
2261 */
2262 exist_attno = findAttrByName(attributeName, inhSchema);
2263 if (exist_attno > 0)
2264 {
2265 Oid defTypeId;
2266 int32 deftypmod;
2267 Oid defCollId;
2268
2269 /*
2270 * Yes, try to merge the two column definitions. They must
2271 * have the same type, typmod, and collation.
2272 */
2273 ereport(NOTICE,
2274 (errmsg("merging multiple inherited definitions of column \"%s\"",
2275 attributeName)));
2276 def = (ColumnDef *) list_nth(inhSchema, exist_attno - 1);
2277 typenameTypeIdAndMod(NULL, def->typeName, &defTypeId, &deftypmod);
2278 if (defTypeId != attribute->atttypid ||
2279 deftypmod != attribute->atttypmod)
2280 ereport(ERROR,
2281 (errcode(ERRCODE_DATATYPE_MISMATCH),
2282 errmsg("inherited column \"%s\" has a type conflict",
2283 attributeName),
2284 errdetail("%s versus %s",
2285 format_type_with_typemod(defTypeId,
2286 deftypmod),
2287 format_type_with_typemod(attribute->atttypid,
2288 attribute->atttypmod))));
2289 defCollId = GetColumnDefCollation(NULL, def, defTypeId);
2290 if (defCollId != attribute->attcollation)
2291 ereport(ERROR,
2292 (errcode(ERRCODE_COLLATION_MISMATCH),
2293 errmsg("inherited column \"%s\" has a collation conflict",
2294 attributeName),
2295 errdetail("\"%s\" versus \"%s\"",
2296 get_collation_name(defCollId),
2297 get_collation_name(attribute->attcollation))));
2298
2299 /* Copy storage parameter */
2300 if (def->storage == 0)
2301 def->storage = attribute->attstorage;
2302 else if (def->storage != attribute->attstorage)
2303 ereport(ERROR,
2304 (errcode(ERRCODE_DATATYPE_MISMATCH),
2305 errmsg("inherited column \"%s\" has a storage parameter conflict",
2306 attributeName),
2307 errdetail("%s versus %s",
2308 storage_name(def->storage),
2309 storage_name(attribute->attstorage))));
2310
2311 def->inhcount++;
2312 /* Merge of NOT NULL constraints = OR 'em together */
2313 def->is_not_null |= attribute->attnotnull;
2314 /* Default and other constraints are handled below */
2315 newattno[parent_attno - 1] = exist_attno;
2316
2317 /* Check for GENERATED conflicts */
2318 if (def->generated != attribute->attgenerated)
2319 ereport(ERROR,
2320 (errcode(ERRCODE_DATATYPE_MISMATCH),
2321 errmsg("inherited column \"%s\" has a generation conflict",
2322 attributeName)));
2323 }
2324 else
2325 {
2326 /*
2327 * No, create a new inherited column
2328 */
2329 def = makeNode(ColumnDef);
2330 def->colname = pstrdup(attributeName);
2331 def->typeName = makeTypeNameFromOid(attribute->atttypid,
2332 attribute->atttypmod);
2333 def->inhcount = 1;
2334 def->is_local = false;
2335 def->is_not_null = attribute->attnotnull;
2336 def->is_from_type = false;
2337 def->storage = attribute->attstorage;
2338 def->raw_default = NULL;
2339 def->cooked_default = NULL;
2340 def->generated = attribute->attgenerated;
2341 def->collClause = NULL;
2342 def->collOid = attribute->attcollation;
2343 def->constraints = NIL;
2344 def->location = -1;
2345 inhSchema = lappend(inhSchema, def);
2346 newattno[parent_attno - 1] = ++child_attno;
2347 }
2348
2349 /*
2350 * Copy default if any
2351 */
2352 if (attribute->atthasdef)
2353 {
2354 Node *this_default = NULL;
2355 AttrDefault *attrdef;
2356 int i;
2357
2358 /* Find default in constraint structure */
2359 Assert(constr != NULL);
2360 attrdef = constr->defval;
2361 for (i = 0; i < constr->num_defval; i++)
2362 {
2363 if (attrdef[i].adnum == parent_attno)
2364 {
2365 this_default = stringToNode(attrdef[i].adbin);
2366 break;
2367 }
2368 }
2369 Assert(this_default != NULL);
2370
2371 /*
2372 * If default expr could contain any vars, we'd need to fix
2373 * 'em, but it can't; so default is ready to apply to child.
2374 *
2375 * If we already had a default from some prior parent, check
2376 * to see if they are the same. If so, no problem; if not,
2377 * mark the column as having a bogus default. Below, we will
2378 * complain if the bogus default isn't overridden by the child
2379 * schema.
2380 */
2381 Assert(def->raw_default == NULL);
2382 if (def->cooked_default == NULL)
2383 def->cooked_default = this_default;
2384 else if (!equal(def->cooked_default, this_default))
2385 {
2386 def->cooked_default = &bogus_marker;
2387 have_bogus_defaults = true;
2388 }
2389 }
2390 }
2391
2392 /*
2393 * Now copy the CHECK constraints of this parent, adjusting attnos
2394 * using the completed newattno[] map. Identically named constraints
2395 * are merged if possible, else we throw error.
2396 */
2397 if (constr && constr->num_check > 0)
2398 {
2399 ConstrCheck *check = constr->check;
2400 int i;
2401
2402 for (i = 0; i < constr->num_check; i++)
2403 {
2404 char *name = check[i].ccname;
2405 Node *expr;
2406 bool found_whole_row;
2407
2408 /* ignore if the constraint is non-inheritable */
2409 if (check[i].ccnoinherit)
2410 continue;
2411
2412 /* Adjust Vars to match new table's column numbering */
2413 expr = map_variable_attnos(stringToNode(check[i].ccbin),
2414 1, 0,
2415 newattno, tupleDesc->natts,
2416 InvalidOid, &found_whole_row);
2417
2418 /*
2419 * For the moment we have to reject whole-row variables. We
2420 * could convert them, if we knew the new table's rowtype OID,
2421 * but that hasn't been assigned yet.
2422 */
2423 if (found_whole_row)
2424 ereport(ERROR,
2425 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2426 errmsg("cannot convert whole-row table reference"),
2427 errdetail("Constraint \"%s\" contains a whole-row reference to table \"%s\".",
2428 name,
2429 RelationGetRelationName(relation))));
2430
2431 /* check for duplicate */
2432 if (!MergeCheckConstraint(constraints, name, expr))
2433 {
2434 /* nope, this is a new one */
2435 CookedConstraint *cooked;
2436
2437 cooked = (CookedConstraint *) palloc(sizeof(CookedConstraint));
2438 cooked->contype = CONSTR_CHECK;
2439 cooked->conoid = InvalidOid; /* until created */
2440 cooked->name = pstrdup(name);
2441 cooked->attnum = 0; /* not used for constraints */
2442 cooked->expr = expr;
2443 cooked->skip_validation = false;
2444 cooked->is_local = false;
2445 cooked->inhcount = 1;
2446 cooked->is_no_inherit = false;
2447 constraints = lappend(constraints, cooked);
2448 }
2449 }
2450 }
2451
2452 pfree(newattno);
2453
2454 /*
2455 * Close the parent rel, but keep our lock on it until xact commit.
2456 * That will prevent someone else from deleting or ALTERing the parent
2457 * before the child is committed.
2458 */
2459 table_close(relation, NoLock);
2460 }
2461
2462 /*
2463 * If we had no inherited attributes, the result schema is just the
2464 * explicitly declared columns. Otherwise, we need to merge the declared
2465 * columns into the inherited schema list. Although, we never have any
2466 * explicitly declared columns if the table is a partition.
2467 */
2468 if (inhSchema != NIL)
2469 {
2470 int schema_attno = 0;
2471
2472 foreach(entry, schema)
2473 {
2474 ColumnDef *newdef = lfirst(entry);
2475 char *attributeName = newdef->colname;
2476 int exist_attno;
2477
2478 schema_attno++;
2479
2480 /*
2481 * Does it conflict with some previously inherited column?
2482 */
2483 exist_attno = findAttrByName(attributeName, inhSchema);
2484 if (exist_attno > 0)
2485 {
2486 ColumnDef *def;
2487 Oid defTypeId,
2488 newTypeId;
2489 int32 deftypmod,
2490 newtypmod;
2491 Oid defcollid,
2492 newcollid;
2493
2494 /*
2495 * Partitions have only one parent and have no column
2496 * definitions of their own, so conflict should never occur.
2497 */
2498 Assert(!is_partition);
2499
2500 /*
2501 * Yes, try to merge the two column definitions. They must
2502 * have the same type, typmod, and collation.
2503 */
2504 if (exist_attno == schema_attno)
2505 ereport(NOTICE,
2506 (errmsg("merging column \"%s\" with inherited definition",
2507 attributeName)));
2508 else
2509 ereport(NOTICE,
2510 (errmsg("moving and merging column \"%s\" with inherited definition", attributeName),
2511 errdetail("User-specified column moved to the position of the inherited column.")));
2512 def = (ColumnDef *) list_nth(inhSchema, exist_attno - 1);
2513 typenameTypeIdAndMod(NULL, def->typeName, &defTypeId, &deftypmod);
2514 typenameTypeIdAndMod(NULL, newdef->typeName, &newTypeId, &newtypmod);
2515 if (defTypeId != newTypeId || deftypmod != newtypmod)
2516 ereport(ERROR,
2517 (errcode(ERRCODE_DATATYPE_MISMATCH),
2518 errmsg("column \"%s\" has a type conflict",
2519 attributeName),
2520 errdetail("%s versus %s",
2521 format_type_with_typemod(defTypeId,
2522 deftypmod),
2523 format_type_with_typemod(newTypeId,
2524 newtypmod))));
2525 defcollid = GetColumnDefCollation(NULL, def, defTypeId);
2526 newcollid = GetColumnDefCollation(NULL, newdef, newTypeId);
2527 if (defcollid != newcollid)
2528 ereport(ERROR,
2529 (errcode(ERRCODE_COLLATION_MISMATCH),
2530 errmsg("column \"%s\" has a collation conflict",
2531 attributeName),
2532 errdetail("\"%s\" versus \"%s\"",
2533 get_collation_name(defcollid),
2534 get_collation_name(newcollid))));
2535
2536 /*
2537 * Identity is never inherited. The new column can have an
2538 * identity definition, so we always just take that one.
2539 */
2540 def->identity = newdef->identity;
2541
2542 /* Copy storage parameter */
2543 if (def->storage == 0)
2544 def->storage = newdef->storage;
2545 else if (newdef->storage != 0 && def->storage != newdef->storage)
2546 ereport(ERROR,
2547 (errcode(ERRCODE_DATATYPE_MISMATCH),
2548 errmsg("column \"%s\" has a storage parameter conflict",
2549 attributeName),
2550 errdetail("%s versus %s",
2551 storage_name(def->storage),
2552 storage_name(newdef->storage))));
2553
2554 /* Mark the column as locally defined */
2555 def->is_local = true;
2556 /* Merge of NOT NULL constraints = OR 'em together */
2557 def->is_not_null |= newdef->is_not_null;
2558 /* If new def has a default, override previous default */
2559 if (newdef->raw_default != NULL)
2560 {
2561 def->raw_default = newdef->raw_default;
2562 def->cooked_default = newdef->cooked_default;
2563 }
2564 }
2565 else
2566 {
2567 /*
2568 * No, attach new column to result schema
2569 */
2570 inhSchema = lappend(inhSchema, newdef);
2571 }
2572 }
2573
2574 schema = inhSchema;
2575
2576 /*
2577 * Check that we haven't exceeded the legal # of columns after merging
2578 * in inherited columns.
2579 */
2580 if (list_length(schema) > MaxHeapAttributeNumber)
2581 ereport(ERROR,
2582 (errcode(ERRCODE_TOO_MANY_COLUMNS),
2583 errmsg("tables can have at most %d columns",
2584 MaxHeapAttributeNumber)));
2585 }
2586
2587 /*
2588 * Now that we have the column definition list for a partition, we can
2589 * check whether the columns referenced in the column constraint specs
2590 * actually exist. Also, we merge NOT NULL and defaults into each
2591 * corresponding column definition.
2592 */
2593 if (is_partition)
2594 {
2595 foreach(entry, saved_schema)
2596 {
2597 ColumnDef *restdef = lfirst(entry);
2598 bool found = false;
2599 ListCell *l;
2600
2601 foreach(l, schema)
2602 {
2603 ColumnDef *coldef = lfirst(l);
2604
2605 if (strcmp(coldef->colname, restdef->colname) == 0)
2606 {
2607 found = true;
2608 coldef->is_not_null |= restdef->is_not_null;
2609
2610 /*
2611 * Override the parent's default value for this column
2612 * (coldef->cooked_default) with the partition's local
2613 * definition (restdef->raw_default), if there's one. It
2614 * should be physically impossible to get a cooked default
2615 * in the local definition or a raw default in the
2616 * inherited definition, but make sure they're nulls, for
2617 * future-proofing.
2618 */
2619 Assert(restdef->cooked_default == NULL);
2620 Assert(coldef->raw_default == NULL);
2621 if (restdef->raw_default)
2622 {
2623 coldef->raw_default = restdef->raw_default;
2624 coldef->cooked_default = NULL;
2625 }
2626 }
2627 }
2628
2629 /* complain for constraints on columns not in parent */
2630 if (!found)
2631 ereport(ERROR,
2632 (errcode(ERRCODE_UNDEFINED_COLUMN),
2633 errmsg("column \"%s\" does not exist",
2634 restdef->colname)));
2635 }
2636 }
2637
2638 /*
2639 * If we found any conflicting parent default values, check to make sure
2640 * they were overridden by the child.
2641 */
2642 if (have_bogus_defaults)
2643 {
2644 foreach(entry, schema)
2645 {
2646 ColumnDef *def = lfirst(entry);
2647
2648 if (def->cooked_default == &bogus_marker)
2649 ereport(ERROR,
2650 (errcode(ERRCODE_INVALID_COLUMN_DEFINITION),
2651 errmsg("column \"%s\" inherits conflicting default values",
2652 def->colname),
2653 errhint("To resolve the conflict, specify a default explicitly.")));
2654 }
2655 }
2656
2657 *supconstr = constraints;
2658 return schema;
2659}
2660
2661
2662/*
2663 * MergeCheckConstraint
2664 * Try to merge an inherited CHECK constraint with previous ones
2665 *
2666 * If we inherit identically-named constraints from multiple parents, we must
2667 * merge them, or throw an error if they don't have identical definitions.
2668 *
2669 * constraints is a list of CookedConstraint structs for previous constraints.
2670 *
2671 * Returns true if merged (constraint is a duplicate), or false if it's
2672 * got a so-far-unique name, or throws error if conflict.
2673 */
2674static bool
2675MergeCheckConstraint(List *constraints, char *name, Node *expr)
2676{
2677 ListCell *lc;
2678
2679 foreach(lc, constraints)
2680 {
2681 CookedConstraint *ccon = (CookedConstraint *) lfirst(lc);
2682
2683 Assert(ccon->contype == CONSTR_CHECK);
2684
2685 /* Non-matching names never conflict */
2686 if (strcmp(ccon->name, name) != 0)
2687 continue;
2688
2689 if (equal(expr, ccon->expr))
2690 {
2691 /* OK to merge */
2692 ccon->inhcount++;
2693 return true;
2694 }
2695
2696 ereport(ERROR,
2697 (errcode(ERRCODE_DUPLICATE_OBJECT),
2698 errmsg("check constraint name \"%s\" appears multiple times but with different expressions",
2699 name)));
2700 }
2701
2702 return false;
2703}
2704
2705
2706/*
2707 * StoreCatalogInheritance
2708 * Updates the system catalogs with proper inheritance information.
2709 *
2710 * supers is a list of the OIDs of the new relation's direct ancestors.
2711 */
2712static void
2713StoreCatalogInheritance(Oid relationId, List *supers,
2714 bool child_is_partition)
2715{
2716 Relation relation;
2717 int32 seqNumber;
2718 ListCell *entry;
2719
2720 /*
2721 * sanity checks
2722 */
2723 AssertArg(OidIsValid(relationId));
2724
2725 if (supers == NIL)
2726 return;
2727
2728 /*
2729 * Store INHERITS information in pg_inherits using direct ancestors only.
2730 * Also enter dependencies on the direct ancestors, and make sure they are
2731 * marked with relhassubclass = true.
2732 *
2733 * (Once upon a time, both direct and indirect ancestors were found here
2734 * and then entered into pg_ipl. Since that catalog doesn't exist
2735 * anymore, there's no need to look for indirect ancestors.)
2736 */
2737 relation = table_open(InheritsRelationId, RowExclusiveLock);
2738
2739 seqNumber = 1;
2740 foreach(entry, supers)
2741 {
2742 Oid parentOid = lfirst_oid(entry);
2743
2744 StoreCatalogInheritance1(relationId, parentOid, seqNumber, relation,
2745 child_is_partition);
2746 seqNumber++;
2747 }
2748
2749 table_close(relation, RowExclusiveLock);
2750}
2751
2752/*
2753 * Make catalog entries showing relationId as being an inheritance child
2754 * of parentOid. inhRelation is the already-opened pg_inherits catalog.
2755 */
2756static void
2757StoreCatalogInheritance1(Oid relationId, Oid parentOid,
2758 int32 seqNumber, Relation inhRelation,
2759 bool child_is_partition)
2760{
2761 ObjectAddress childobject,
2762 parentobject;
2763
2764 /* store the pg_inherits row */
2765 StoreSingleInheritance(relationId, parentOid, seqNumber);
2766
2767 /*
2768 * Store a dependency too
2769 */
2770 parentobject.classId = RelationRelationId;
2771 parentobject.objectId = parentOid;
2772 parentobject.objectSubId = 0;
2773 childobject.classId = RelationRelationId;
2774 childobject.objectId = relationId;
2775 childobject.objectSubId = 0;
2776
2777 recordDependencyOn(&childobject, &parentobject,
2778 child_dependency_type(child_is_partition));
2779
2780 /*
2781 * Post creation hook of this inheritance. Since object_access_hook
2782 * doesn't take multiple object identifiers, we relay oid of parent
2783 * relation using auxiliary_id argument.
2784 */
2785 InvokeObjectPostAlterHookArg(InheritsRelationId,
2786 relationId, 0,
2787 parentOid, false);
2788
2789 /*
2790 * Mark the parent as having subclasses.
2791 */
2792 SetRelationHasSubclass(parentOid, true);
2793}
2794
2795/*
2796 * Look for an existing schema entry with the given name.
2797 *
2798 * Returns the index (starting with 1) if attribute already exists in schema,
2799 * 0 if it doesn't.
2800 */
2801static int
2802findAttrByName(const char *attributeName, List *schema)
2803{
2804 ListCell *s;
2805 int i = 1;
2806
2807 foreach(s, schema)
2808 {
2809 ColumnDef *def = lfirst(s);
2810
2811 if (strcmp(attributeName, def->colname) == 0)
2812 return i;
2813
2814 i++;
2815 }
2816 return 0;
2817}
2818
2819
2820/*
2821 * SetRelationHasSubclass
2822 * Set the value of the relation's relhassubclass field in pg_class.
2823 *
2824 * NOTE: caller must be holding an appropriate lock on the relation.
2825 * ShareUpdateExclusiveLock is sufficient.
2826 *
2827 * NOTE: an important side-effect of this operation is that an SI invalidation
2828 * message is sent out to all backends --- including me --- causing plans
2829 * referencing the relation to be rebuilt with the new list of children.
2830 * This must happen even if we find that no change is needed in the pg_class
2831 * row.
2832 */
2833void
2834SetRelationHasSubclass(Oid relationId, bool relhassubclass)
2835{
2836 Relation relationRelation;
2837 HeapTuple tuple;
2838 Form_pg_class classtuple;
2839
2840 /*
2841 * Fetch a modifiable copy of the tuple, modify it, update pg_class.
2842 */
2843 relationRelation = table_open(RelationRelationId, RowExclusiveLock);
2844 tuple = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(relationId));
2845 if (!HeapTupleIsValid(tuple))
2846 elog(ERROR, "cache lookup failed for relation %u", relationId);
2847 classtuple = (Form_pg_class) GETSTRUCT(tuple);
2848
2849 if (classtuple->relhassubclass != relhassubclass)
2850 {
2851 classtuple->relhassubclass = relhassubclass;
2852 CatalogTupleUpdate(relationRelation, &tuple->t_self, tuple);
2853 }
2854 else
2855 {
2856 /* no need to change tuple, but force relcache rebuild anyway */
2857 CacheInvalidateRelcacheByTuple(tuple);
2858 }
2859
2860 heap_freetuple(tuple);
2861 table_close(relationRelation, RowExclusiveLock);
2862}
2863
2864/*
2865 * renameatt_check - basic sanity checks before attribute rename
2866 */
2867static void
2868renameatt_check(Oid myrelid, Form_pg_class classform, bool recursing)
2869{
2870 char relkind = classform->relkind;
2871
2872 if (classform->reloftype && !recursing)
2873 ereport(ERROR,
2874 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
2875 errmsg("cannot rename column of typed table")));
2876
2877 /*
2878 * Renaming the columns of sequences or toast tables doesn't actually
2879 * break anything from the system's point of view, since internal
2880 * references are by attnum. But it doesn't seem right to allow users to
2881 * change names that are hardcoded into the system, hence the following
2882 * restriction.
2883 */
2884 if (relkind != RELKIND_RELATION &&
2885 relkind != RELKIND_VIEW &&
2886 relkind != RELKIND_MATVIEW &&
2887 relkind != RELKIND_COMPOSITE_TYPE &&
2888 relkind != RELKIND_INDEX &&
2889 relkind != RELKIND_PARTITIONED_INDEX &&
2890 relkind != RELKIND_FOREIGN_TABLE &&
2891 relkind != RELKIND_PARTITIONED_TABLE)
2892 ereport(ERROR,
2893 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
2894 errmsg("\"%s\" is not a table, view, materialized view, composite type, index, or foreign table",
2895 NameStr(classform->relname))));
2896
2897 /*
2898 * permissions checking. only the owner of a class can change its schema.
2899 */
2900 if (!pg_class_ownercheck(myrelid, GetUserId()))
2901 aclcheck_error(ACLCHECK_NOT_OWNER, get_relkind_objtype(get_rel_relkind(myrelid)),
2902 NameStr(classform->relname));
2903 if (!allowSystemTableMods && IsSystemClass(myrelid, classform))
2904 ereport(ERROR,
2905 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
2906 errmsg("permission denied: \"%s\" is a system catalog",
2907 NameStr(classform->relname))));
2908}
2909
2910/*
2911 * renameatt_internal - workhorse for renameatt
2912 *
2913 * Return value is the attribute number in the 'myrelid' relation.
2914 */
2915static AttrNumber
2916renameatt_internal(Oid myrelid,
2917 const char *oldattname,
2918 const char *newattname,
2919 bool recurse,
2920 bool recursing,
2921 int expected_parents,
2922 DropBehavior behavior)
2923{
2924 Relation targetrelation;
2925 Relation attrelation;
2926 HeapTuple atttup;
2927 Form_pg_attribute attform;
2928 AttrNumber attnum;
2929
2930 /*
2931 * Grab an exclusive lock on the target table, which we will NOT release
2932 * until end of transaction.
2933 */
2934 targetrelation = relation_open(myrelid, AccessExclusiveLock);
2935 renameatt_check(myrelid, RelationGetForm(targetrelation), recursing);
2936
2937 /*
2938 * if the 'recurse' flag is set then we are supposed to rename this
2939 * attribute in all classes that inherit from 'relname' (as well as in
2940 * 'relname').
2941 *
2942 * any permissions or problems with duplicate attributes will cause the
2943 * whole transaction to abort, which is what we want -- all or nothing.
2944 */
2945 if (recurse)
2946 {
2947 List *child_oids,
2948 *child_numparents;
2949 ListCell *lo,
2950 *li;
2951
2952 /*
2953 * we need the number of parents for each child so that the recursive
2954 * calls to renameatt() can determine whether there are any parents
2955 * outside the inheritance hierarchy being processed.
2956 */
2957 child_oids = find_all_inheritors(myrelid, AccessExclusiveLock,
2958 &child_numparents);
2959
2960 /*
2961 * find_all_inheritors does the recursive search of the inheritance
2962 * hierarchy, so all we have to do is process all of the relids in the
2963 * list that it returns.
2964 */
2965 forboth(lo, child_oids, li, child_numparents)
2966 {
2967 Oid childrelid = lfirst_oid(lo);
2968 int numparents = lfirst_int(li);
2969
2970 if (childrelid == myrelid)
2971 continue;
2972 /* note we need not recurse again */
2973 renameatt_internal(childrelid, oldattname, newattname, false, true, numparents, behavior);
2974 }
2975 }
2976 else
2977 {
2978 /*
2979 * If we are told not to recurse, there had better not be any child
2980 * tables; else the rename would put them out of step.
2981 *
2982 * expected_parents will only be 0 if we are not already recursing.
2983 */
2984 if (expected_parents == 0 &&
2985 find_inheritance_children(myrelid, NoLock) != NIL)
2986 ereport(ERROR,
2987 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
2988 errmsg("inherited column \"%s\" must be renamed in child tables too",
2989 oldattname)));
2990 }
2991
2992 /* rename attributes in typed tables of composite type */
2993 if (targetrelation->rd_rel->relkind == RELKIND_COMPOSITE_TYPE)
2994 {
2995 List *child_oids;
2996 ListCell *lo;
2997
2998 child_oids = find_typed_table_dependencies(targetrelation->rd_rel->reltype,
2999 RelationGetRelationName(targetrelation),
3000 behavior);
3001
3002 foreach(lo, child_oids)
3003 renameatt_internal(lfirst_oid(lo), oldattname, newattname, true, true, 0, behavior);
3004 }
3005
3006 attrelation = table_open(AttributeRelationId, RowExclusiveLock);
3007
3008 atttup = SearchSysCacheCopyAttName(myrelid, oldattname);
3009 if (!HeapTupleIsValid(atttup))
3010 ereport(ERROR,
3011 (errcode(ERRCODE_UNDEFINED_COLUMN),
3012 errmsg("column \"%s\" does not exist",
3013 oldattname)));
3014 attform = (Form_pg_attribute) GETSTRUCT(atttup);
3015
3016 attnum = attform->attnum;
3017 if (attnum <= 0)
3018 ereport(ERROR,
3019 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3020 errmsg("cannot rename system column \"%s\"",
3021 oldattname)));
3022
3023 /*
3024 * if the attribute is inherited, forbid the renaming. if this is a
3025 * top-level call to renameatt(), then expected_parents will be 0, so the
3026 * effect of this code will be to prohibit the renaming if the attribute
3027 * is inherited at all. if this is a recursive call to renameatt(),
3028 * expected_parents will be the number of parents the current relation has
3029 * within the inheritance hierarchy being processed, so we'll prohibit the
3030 * renaming only if there are additional parents from elsewhere.
3031 */
3032 if (attform->attinhcount > expected_parents)
3033 ereport(ERROR,
3034 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
3035 errmsg("cannot rename inherited column \"%s\"",
3036 oldattname)));
3037
3038 /* new name should not already exist */
3039 (void) check_for_column_name_collision(targetrelation, newattname, false);
3040
3041 /* apply the update */
3042 namestrcpy(&(attform->attname), newattname);
3043
3044 CatalogTupleUpdate(attrelation, &atttup->t_self, atttup);
3045
3046 InvokeObjectPostAlterHook(RelationRelationId, myrelid, attnum);
3047
3048 heap_freetuple(atttup);
3049
3050 table_close(attrelation, RowExclusiveLock);
3051
3052 relation_close(targetrelation, NoLock); /* close rel but keep lock */
3053
3054 return attnum;
3055}
3056
3057/*
3058 * Perform permissions and integrity checks before acquiring a relation lock.
3059 */
3060static void
3061RangeVarCallbackForRenameAttribute(const RangeVar *rv, Oid relid, Oid oldrelid,
3062 void *arg)
3063{
3064 HeapTuple tuple;
3065 Form_pg_class form;
3066
3067 tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
3068 if (!HeapTupleIsValid(tuple))
3069 return; /* concurrently dropped */
3070 form = (Form_pg_class) GETSTRUCT(tuple);
3071 renameatt_check(relid, form, false);
3072 ReleaseSysCache(tuple);
3073}
3074
3075/*
3076 * renameatt - changes the name of an attribute in a relation
3077 *
3078 * The returned ObjectAddress is that of the renamed column.
3079 */
3080ObjectAddress
3081renameatt(RenameStmt *stmt)
3082{
3083 Oid relid;
3084 AttrNumber attnum;
3085 ObjectAddress address;
3086
3087 /* lock level taken here should match renameatt_internal */
3088 relid = RangeVarGetRelidExtended(stmt->relation, AccessExclusiveLock,
3089 stmt->missing_ok ? RVR_MISSING_OK : 0,
3090 RangeVarCallbackForRenameAttribute,
3091 NULL);
3092
3093 if (!OidIsValid(relid))
3094 {
3095 ereport(NOTICE,
3096 (errmsg("relation \"%s\" does not exist, skipping",
3097 stmt->relation->relname)));
3098 return InvalidObjectAddress;
3099 }
3100
3101 attnum =
3102 renameatt_internal(relid,
3103 stmt->subname, /* old att name */
3104 stmt->newname, /* new att name */
3105 stmt->relation->inh, /* recursive? */
3106 false, /* recursing? */
3107 0, /* expected inhcount */
3108 stmt->behavior);
3109
3110 ObjectAddressSubSet(address, RelationRelationId, relid, attnum);
3111
3112 return address;
3113}
3114
3115/*
3116 * same logic as renameatt_internal
3117 */
3118static ObjectAddress
3119rename_constraint_internal(Oid myrelid,
3120 Oid mytypid,
3121 const char *oldconname,
3122 const char *newconname,
3123 bool recurse,
3124 bool recursing,
3125 int expected_parents)
3126{
3127 Relation targetrelation = NULL;
3128 Oid constraintOid;
3129 HeapTuple tuple;
3130 Form_pg_constraint con;
3131 ObjectAddress address;
3132
3133 AssertArg(!myrelid || !mytypid);
3134
3135 if (mytypid)
3136 {
3137 constraintOid = get_domain_constraint_oid(mytypid, oldconname, false);
3138 }
3139 else
3140 {
3141 targetrelation = relation_open(myrelid, AccessExclusiveLock);
3142
3143 /*
3144 * don't tell it whether we're recursing; we allow changing typed
3145 * tables here
3146 */
3147 renameatt_check(myrelid, RelationGetForm(targetrelation), false);
3148
3149 constraintOid = get_relation_constraint_oid(myrelid, oldconname, false);
3150 }
3151
3152 tuple = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constraintOid));
3153 if (!HeapTupleIsValid(tuple))
3154 elog(ERROR, "cache lookup failed for constraint %u",
3155 constraintOid);
3156 con = (Form_pg_constraint) GETSTRUCT(tuple);
3157
3158 if (myrelid && con->contype == CONSTRAINT_CHECK && !con->connoinherit)
3159 {
3160 if (recurse)
3161 {
3162 List *child_oids,
3163 *child_numparents;
3164 ListCell *lo,
3165 *li;
3166
3167 child_oids = find_all_inheritors(myrelid, AccessExclusiveLock,
3168 &child_numparents);
3169
3170 forboth(lo, child_oids, li, child_numparents)
3171 {
3172 Oid childrelid = lfirst_oid(lo);
3173 int numparents = lfirst_int(li);
3174
3175 if (childrelid == myrelid)
3176 continue;
3177
3178 rename_constraint_internal(childrelid, InvalidOid, oldconname, newconname, false, true, numparents);
3179 }
3180 }
3181 else
3182 {
3183 if (expected_parents == 0 &&
3184 find_inheritance_children(myrelid, NoLock) != NIL)
3185 ereport(ERROR,
3186 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
3187 errmsg("inherited constraint \"%s\" must be renamed in child tables too",
3188 oldconname)));
3189 }
3190
3191 if (con->coninhcount > expected_parents)
3192 ereport(ERROR,
3193 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
3194 errmsg("cannot rename inherited constraint \"%s\"",
3195 oldconname)));
3196 }
3197
3198 if (con->conindid
3199 && (con->contype == CONSTRAINT_PRIMARY
3200 || con->contype == CONSTRAINT_UNIQUE
3201 || con->contype == CONSTRAINT_EXCLUSION))
3202 /* rename the index; this renames the constraint as well */
3203 RenameRelationInternal(con->conindid, newconname, false, true);
3204 else
3205 RenameConstraintById(constraintOid, newconname);
3206
3207 ObjectAddressSet(address, ConstraintRelationId, constraintOid);
3208
3209 ReleaseSysCache(tuple);
3210
3211 if (targetrelation)
3212 {
3213 /*
3214 * Invalidate relcache so as others can see the new constraint name.
3215 */
3216 CacheInvalidateRelcache(targetrelation);
3217
3218 relation_close(targetrelation, NoLock); /* close rel but keep lock */
3219 }
3220
3221 return address;
3222}
3223
3224ObjectAddress
3225RenameConstraint(RenameStmt *stmt)
3226{
3227 Oid relid = InvalidOid;
3228 Oid typid = InvalidOid;
3229
3230 if (stmt->renameType == OBJECT_DOMCONSTRAINT)
3231 {
3232 Relation rel;
3233 HeapTuple tup;
3234
3235 typid = typenameTypeId(NULL, makeTypeNameFromNameList(castNode(List, stmt->object)));
3236 rel = table_open(TypeRelationId, RowExclusiveLock);
3237 tup = SearchSysCache1(TYPEOID, ObjectIdGetDatum(typid));
3238 if (!HeapTupleIsValid(tup))
3239 elog(ERROR, "cache lookup failed for type %u", typid);
3240 checkDomainOwner(tup);
3241 ReleaseSysCache(tup);
3242 table_close(rel, NoLock);
3243 }
3244 else
3245 {
3246 /* lock level taken here should match rename_constraint_internal */
3247 relid = RangeVarGetRelidExtended(stmt->relation, AccessExclusiveLock,
3248 stmt->missing_ok ? RVR_MISSING_OK : 0,
3249 RangeVarCallbackForRenameAttribute,
3250 NULL);
3251 if (!OidIsValid(relid))
3252 {
3253 ereport(NOTICE,
3254 (errmsg("relation \"%s\" does not exist, skipping",
3255 stmt->relation->relname)));
3256 return InvalidObjectAddress;
3257 }
3258 }
3259
3260 return
3261 rename_constraint_internal(relid, typid,
3262 stmt->subname,
3263 stmt->newname,
3264 (stmt->relation &&
3265 stmt->relation->inh), /* recursive? */
3266 false, /* recursing? */
3267 0 /* expected inhcount */ );
3268
3269}
3270
3271/*
3272 * Execute ALTER TABLE/INDEX/SEQUENCE/VIEW/MATERIALIZED VIEW/FOREIGN TABLE
3273 * RENAME
3274 */
3275ObjectAddress
3276RenameRelation(RenameStmt *stmt)
3277{
3278 bool is_index = stmt->renameType == OBJECT_INDEX;
3279 Oid relid;
3280 ObjectAddress address;
3281
3282 /*
3283 * Grab an exclusive lock on the target table, index, sequence, view,
3284 * materialized view, or foreign table, which we will NOT release until
3285 * end of transaction.
3286 *
3287 * Lock level used here should match RenameRelationInternal, to avoid lock
3288 * escalation.
3289 */
3290 relid = RangeVarGetRelidExtended(stmt->relation,
3291 is_index ? ShareUpdateExclusiveLock : AccessExclusiveLock,
3292 stmt->missing_ok ? RVR_MISSING_OK : 0,
3293 RangeVarCallbackForAlterRelation,
3294 (void *) stmt);
3295
3296 if (!OidIsValid(relid))
3297 {
3298 ereport(NOTICE,
3299 (errmsg("relation \"%s\" does not exist, skipping",
3300 stmt->relation->relname)));
3301 return InvalidObjectAddress;
3302 }
3303
3304 /* Do the work */
3305 RenameRelationInternal(relid, stmt->newname, false, is_index);
3306
3307 ObjectAddressSet(address, RelationRelationId, relid);
3308
3309 return address;
3310}
3311
3312/*
3313 * RenameRelationInternal - change the name of a relation
3314 */
3315void
3316RenameRelationInternal(Oid myrelid, const char *newrelname, bool is_internal, bool is_index)
3317{
3318 Relation targetrelation;
3319 Relation relrelation; /* for RELATION relation */
3320 HeapTuple reltup;
3321 Form_pg_class relform;
3322 Oid namespaceId;
3323
3324 /*
3325 * Grab a lock on the target relation, which we will NOT release until end
3326 * of transaction. We need at least a self-exclusive lock so that
3327 * concurrent DDL doesn't overwrite the rename if they start updating
3328 * while still seeing the old version. The lock also guards against
3329 * triggering relcache reloads in concurrent sessions, which might not
3330 * handle this information changing under them. For indexes, we can use a
3331 * reduced lock level because RelationReloadIndexInfo() handles indexes
3332 * specially.
3333 */
3334 targetrelation = relation_open(myrelid, is_index ? ShareUpdateExclusiveLock : AccessExclusiveLock);
3335 namespaceId = RelationGetNamespace(targetrelation);
3336
3337 /*
3338 * Find relation's pg_class tuple, and make sure newrelname isn't in use.
3339 */
3340 relrelation = table_open(RelationRelationId, RowExclusiveLock);
3341
3342 reltup = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(myrelid));
3343 if (!HeapTupleIsValid(reltup)) /* shouldn't happen */
3344 elog(ERROR, "cache lookup failed for relation %u", myrelid);
3345 relform = (Form_pg_class) GETSTRUCT(reltup);
3346
3347 if (get_relname_relid(newrelname, namespaceId) != InvalidOid)
3348 ereport(ERROR,
3349 (errcode(ERRCODE_DUPLICATE_TABLE),
3350 errmsg("relation \"%s\" already exists",
3351 newrelname)));
3352
3353 /*
3354 * Update pg_class tuple with new relname. (Scribbling on reltup is OK
3355 * because it's a copy...)
3356 */
3357 namestrcpy(&(relform->relname), newrelname);
3358
3359 CatalogTupleUpdate(relrelation, &reltup->t_self, reltup);
3360
3361 InvokeObjectPostAlterHookArg(RelationRelationId, myrelid, 0,
3362 InvalidOid, is_internal);
3363
3364 heap_freetuple(reltup);
3365 table_close(relrelation, RowExclusiveLock);
3366
3367 /*
3368 * Also rename the associated type, if any.
3369 */
3370 if (OidIsValid(targetrelation->rd_rel->reltype))
3371 RenameTypeInternal(targetrelation->rd_rel->reltype,
3372 newrelname, namespaceId);
3373
3374 /*
3375 * Also rename the associated constraint, if any.
3376 */
3377 if (targetrelation->rd_rel->relkind == RELKIND_INDEX ||
3378 targetrelation->rd_rel->relkind == RELKIND_PARTITIONED_INDEX)
3379 {
3380 Oid constraintId = get_index_constraint(myrelid);
3381
3382 if (OidIsValid(constraintId))
3383 RenameConstraintById(constraintId, newrelname);
3384 }
3385
3386 /*
3387 * Close rel, but keep lock!
3388 */
3389 relation_close(targetrelation, NoLock);
3390}
3391
3392/*
3393 * Disallow ALTER TABLE (and similar commands) when the current backend has
3394 * any open reference to the target table besides the one just acquired by
3395 * the calling command; this implies there's an open cursor or active plan.
3396 * We need this check because our lock doesn't protect us against stomping
3397 * on our own foot, only other people's feet!
3398 *
3399 * For ALTER TABLE, the only case known to cause serious trouble is ALTER
3400 * COLUMN TYPE, and some changes are obviously pretty benign, so this could
3401 * possibly be relaxed to only error out for certain types of alterations.
3402 * But the use-case for allowing any of these things is not obvious, so we
3403 * won't work hard at it for now.
3404 *
3405 * We also reject these commands if there are any pending AFTER trigger events
3406 * for the rel. This is certainly necessary for the rewriting variants of
3407 * ALTER TABLE, because they don't preserve tuple TIDs and so the pending
3408 * events would try to fetch the wrong tuples. It might be overly cautious
3409 * in other cases, but again it seems better to err on the side of paranoia.
3410 *
3411 * REINDEX calls this with "rel" referencing the index to be rebuilt; here
3412 * we are worried about active indexscans on the index. The trigger-event
3413 * check can be skipped, since we are doing no damage to the parent table.
3414 *
3415 * The statement name (eg, "ALTER TABLE") is passed for use in error messages.
3416 */
3417void
3418CheckTableNotInUse(Relation rel, const char *stmt)
3419{
3420 int expected_refcnt;
3421
3422 expected_refcnt = rel->rd_isnailed ? 2 : 1;
3423 if (rel->rd_refcnt != expected_refcnt)
3424 ereport(ERROR,
3425 (errcode(ERRCODE_OBJECT_IN_USE),
3426 /* translator: first %s is a SQL command, eg ALTER TABLE */
3427 errmsg("cannot %s \"%s\" because it is being used by active queries in this session",
3428 stmt, RelationGetRelationName(rel))));
3429
3430 if (rel->rd_rel->relkind != RELKIND_INDEX &&
3431 rel->rd_rel->relkind != RELKIND_PARTITIONED_INDEX &&
3432 AfterTriggerPendingOnRel(RelationGetRelid(rel)))
3433 ereport(ERROR,
3434 (errcode(ERRCODE_OBJECT_IN_USE),
3435 /* translator: first %s is a SQL command, eg ALTER TABLE */
3436 errmsg("cannot %s \"%s\" because it has pending trigger events",
3437 stmt, RelationGetRelationName(rel))));
3438}
3439
3440/*
3441 * AlterTableLookupRelation
3442 * Look up, and lock, the OID for the relation named by an alter table
3443 * statement.
3444 */
3445Oid
3446AlterTableLookupRelation(AlterTableStmt *stmt, LOCKMODE lockmode)
3447{
3448 return RangeVarGetRelidExtended(stmt->relation, lockmode,
3449 stmt->missing_ok ? RVR_MISSING_OK : 0,
3450 RangeVarCallbackForAlterRelation,
3451 (void *) stmt);
3452}
3453
3454/*
3455 * AlterTable
3456 * Execute ALTER TABLE, which can be a list of subcommands
3457 *
3458 * ALTER TABLE is performed in three phases:
3459 * 1. Examine subcommands and perform pre-transformation checking.
3460 * 2. Update system catalogs.
3461 * 3. Scan table(s) to check new constraints, and optionally recopy
3462 * the data into new table(s).
3463 * Phase 3 is not performed unless one or more of the subcommands requires
3464 * it. The intention of this design is to allow multiple independent
3465 * updates of the table schema to be performed with only one pass over the
3466 * data.
3467 *
3468 * ATPrepCmd performs phase 1. A "work queue" entry is created for
3469 * each table to be affected (there may be multiple affected tables if the
3470 * commands traverse a table inheritance hierarchy). Also we do preliminary
3471 * validation of the subcommands, including parse transformation of those
3472 * expressions that need to be evaluated with respect to the old table
3473 * schema.
3474 *
3475 * ATRewriteCatalogs performs phase 2 for each affected table. (Note that
3476 * phases 2 and 3 normally do no explicit recursion, since phase 1 already
3477 * did it --- although some subcommands have to recurse in phase 2 instead.)
3478 * Certain subcommands need to be performed before others to avoid
3479 * unnecessary conflicts; for example, DROP COLUMN should come before
3480 * ADD COLUMN. Therefore phase 1 divides the subcommands into multiple
3481 * lists, one for each logical "pass" of phase 2.
3482 *
3483 * ATRewriteTables performs phase 3 for those tables that need it.
3484 *
3485 * Thanks to the magic of MVCC, an error anywhere along the way rolls back
3486 * the whole operation; we don't have to do anything special to clean up.
3487 *
3488 * The caller must lock the relation, with an appropriate lock level
3489 * for the subcommands requested, using AlterTableGetLockLevel(stmt->cmds)
3490 * or higher. We pass the lock level down
3491 * so that we can apply it recursively to inherited tables. Note that the
3492 * lock level we want as we recurse might well be higher than required for
3493 * that specific subcommand. So we pass down the overall lock requirement,
3494 * rather than reassess it at lower levels.
3495 */
3496void
3497AlterTable(Oid relid, LOCKMODE lockmode, AlterTableStmt *stmt)
3498{
3499 Relation rel;
3500
3501 /* Caller is required to provide an adequate lock. */
3502 rel = relation_open(relid, NoLock);
3503
3504 CheckTableNotInUse(rel, "ALTER TABLE");
3505
3506 ATController(stmt, rel, stmt->cmds, stmt->relation->inh, lockmode);
3507}
3508
3509/*
3510 * AlterTableInternal
3511 *
3512 * ALTER TABLE with target specified by OID
3513 *
3514 * We do not reject if the relation is already open, because it's quite
3515 * likely that one or more layers of caller have it open. That means it
3516 * is unsafe to use this entry point for alterations that could break
3517 * existing query plans. On the assumption it's not used for such, we
3518 * don't have to reject pending AFTER triggers, either.
3519 */
3520void
3521AlterTableInternal(Oid relid, List *cmds, bool recurse)
3522{
3523 Relation rel;
3524 LOCKMODE lockmode = AlterTableGetLockLevel(cmds);
3525
3526 rel = relation_open(relid, lockmode);
3527
3528 EventTriggerAlterTableRelid(relid);
3529
3530 ATController(NULL, rel, cmds, recurse, lockmode);
3531}
3532
3533/*
3534 * AlterTableGetLockLevel
3535 *
3536 * Sets the overall lock level required for the supplied list of subcommands.
3537 * Policy for doing this set according to needs of AlterTable(), see
3538 * comments there for overall explanation.
3539 *
3540 * Function is called before and after parsing, so it must give same
3541 * answer each time it is called. Some subcommands are transformed
3542 * into other subcommand types, so the transform must never be made to a
3543 * lower lock level than previously assigned. All transforms are noted below.
3544 *
3545 * Since this is called before we lock the table we cannot use table metadata
3546 * to influence the type of lock we acquire.
3547 *
3548 * There should be no lockmodes hardcoded into the subcommand functions. All
3549 * lockmode decisions for ALTER TABLE are made here only. The one exception is
3550 * ALTER TABLE RENAME which is treated as a different statement type T_RenameStmt
3551 * and does not travel through this section of code and cannot be combined with
3552 * any of the subcommands given here.
3553 *
3554 * Note that Hot Standby only knows about AccessExclusiveLocks on the master
3555 * so any changes that might affect SELECTs running on standbys need to use
3556 * AccessExclusiveLocks even if you think a lesser lock would do, unless you
3557 * have a solution for that also.
3558 *
3559 * Also note that pg_dump uses only an AccessShareLock, meaning that anything
3560 * that takes a lock less than AccessExclusiveLock can change object definitions
3561 * while pg_dump is running. Be careful to check that the appropriate data is
3562 * derived by pg_dump using an MVCC snapshot, rather than syscache lookups,
3563 * otherwise we might end up with an inconsistent dump that can't restore.
3564 */
3565LOCKMODE
3566AlterTableGetLockLevel(List *cmds)
3567{
3568 /*
3569 * This only works if we read catalog tables using MVCC snapshots.
3570 */
3571 ListCell *lcmd;
3572 LOCKMODE lockmode = ShareUpdateExclusiveLock;
3573
3574 foreach(lcmd, cmds)
3575 {
3576 AlterTableCmd *cmd = (AlterTableCmd *) lfirst(lcmd);
3577 LOCKMODE cmd_lockmode = AccessExclusiveLock; /* default for compiler */
3578
3579 switch (cmd->subtype)
3580 {
3581 /*
3582 * These subcommands rewrite the heap, so require full locks.
3583 */
3584 case AT_AddColumn: /* may rewrite heap, in some cases and visible
3585 * to SELECT */
3586 case AT_SetTableSpace: /* must rewrite heap */
3587 case AT_AlterColumnType: /* must rewrite heap */
3588 cmd_lockmode = AccessExclusiveLock;
3589 break;
3590
3591 /*
3592 * These subcommands may require addition of toast tables. If
3593 * we add a toast table to a table currently being scanned, we
3594 * might miss data added to the new toast table by concurrent
3595 * insert transactions.
3596 */
3597 case AT_SetStorage: /* may add toast tables, see
3598 * ATRewriteCatalogs() */
3599 cmd_lockmode = AccessExclusiveLock;
3600 break;
3601
3602 /*
3603 * Removing constraints can affect SELECTs that have been
3604 * optimized assuming the constraint holds true. See also
3605 * CloneFkReferenced.
3606 */
3607 case AT_DropConstraint: /* as DROP INDEX */
3608 case AT_DropNotNull: /* may change some SQL plans */
3609 cmd_lockmode = AccessExclusiveLock;
3610 break;
3611
3612 /*
3613 * Subcommands that may be visible to concurrent SELECTs
3614 */
3615 case AT_DropColumn: /* change visible to SELECT */
3616 case AT_AddColumnToView: /* CREATE VIEW */
3617 case AT_DropOids: /* used to equiv to DropColumn */
3618 case AT_EnableAlwaysRule: /* may change SELECT rules */
3619 case AT_EnableReplicaRule: /* may change SELECT rules */
3620 case AT_EnableRule: /* may change SELECT rules */
3621 case AT_DisableRule: /* may change SELECT rules */
3622 cmd_lockmode = AccessExclusiveLock;
3623 break;
3624
3625 /*
3626 * Changing owner may remove implicit SELECT privileges
3627 */
3628 case AT_ChangeOwner: /* change visible to SELECT */
3629 cmd_lockmode = AccessExclusiveLock;
3630 break;
3631
3632 /*
3633 * Changing foreign table options may affect optimization.
3634 */
3635 case AT_GenericOptions:
3636 case AT_AlterColumnGenericOptions:
3637 cmd_lockmode = AccessExclusiveLock;
3638 break;
3639
3640 /*
3641 * These subcommands affect write operations only.
3642 */
3643 case AT_EnableTrig:
3644 case AT_EnableAlwaysTrig:
3645 case AT_EnableReplicaTrig:
3646 case AT_EnableTrigAll:
3647 case AT_EnableTrigUser:
3648 case AT_DisableTrig:
3649 case AT_DisableTrigAll:
3650 case AT_DisableTrigUser:
3651 cmd_lockmode = ShareRowExclusiveLock;
3652 break;
3653
3654 /*
3655 * These subcommands affect write operations only. XXX
3656 * Theoretically, these could be ShareRowExclusiveLock.
3657 */
3658 case AT_ColumnDefault:
3659 case AT_AlterConstraint:
3660 case AT_AddIndex: /* from ADD CONSTRAINT */
3661 case AT_AddIndexConstraint:
3662 case AT_ReplicaIdentity:
3663 case AT_SetNotNull:
3664 case AT_EnableRowSecurity:
3665 case AT_DisableRowSecurity:
3666 case AT_ForceRowSecurity:
3667 case AT_NoForceRowSecurity:
3668 case AT_AddIdentity:
3669 case AT_DropIdentity:
3670 case AT_SetIdentity:
3671 cmd_lockmode = AccessExclusiveLock;
3672 break;
3673
3674 case AT_AddConstraint:
3675 case AT_ProcessedConstraint: /* becomes AT_AddConstraint */
3676 case AT_AddConstraintRecurse: /* becomes AT_AddConstraint */
3677 case AT_ReAddConstraint: /* becomes AT_AddConstraint */
3678 case AT_ReAddDomainConstraint: /* becomes AT_AddConstraint */
3679 if (IsA(cmd->def, Constraint))
3680 {
3681 Constraint *con = (Constraint *) cmd->def;
3682
3683 switch (con->contype)
3684 {
3685 case CONSTR_EXCLUSION:
3686 case CONSTR_PRIMARY:
3687 case CONSTR_UNIQUE:
3688
3689 /*
3690 * Cases essentially the same as CREATE INDEX. We
3691 * could reduce the lock strength to ShareLock if
3692 * we can work out how to allow concurrent catalog
3693 * updates. XXX Might be set down to
3694 * ShareRowExclusiveLock but requires further
3695 * analysis.
3696 */
3697 cmd_lockmode = AccessExclusiveLock;
3698 break;
3699 case CONSTR_FOREIGN:
3700
3701 /*
3702 * We add triggers to both tables when we add a
3703 * Foreign Key, so the lock level must be at least
3704 * as strong as CREATE TRIGGER.
3705 */
3706 cmd_lockmode = ShareRowExclusiveLock;
3707 break;
3708
3709 default:
3710 cmd_lockmode = AccessExclusiveLock;
3711 }
3712 }
3713 break;
3714
3715 /*
3716 * These subcommands affect inheritance behaviour. Queries
3717 * started before us will continue to see the old inheritance
3718 * behaviour, while queries started after we commit will see
3719 * new behaviour. No need to prevent reads or writes to the
3720 * subtable while we hook it up though. Changing the TupDesc
3721 * may be a problem, so keep highest lock.
3722 */
3723 case AT_AddInherit:
3724 case AT_DropInherit:
3725 cmd_lockmode = AccessExclusiveLock;
3726 break;
3727
3728 /*
3729 * These subcommands affect implicit row type conversion. They
3730 * have affects similar to CREATE/DROP CAST on queries. don't
3731 * provide for invalidating parse trees as a result of such
3732 * changes, so we keep these at AccessExclusiveLock.
3733 */
3734 case AT_AddOf:
3735 case AT_DropOf:
3736 cmd_lockmode = AccessExclusiveLock;
3737 break;
3738
3739 /*
3740 * Only used by CREATE OR REPLACE VIEW which must conflict
3741 * with an SELECTs currently using the view.
3742 */
3743 case AT_ReplaceRelOptions:
3744 cmd_lockmode = AccessExclusiveLock;
3745 break;
3746
3747 /*
3748 * These subcommands affect general strategies for performance
3749 * and maintenance, though don't change the semantic results
3750 * from normal data reads and writes. Delaying an ALTER TABLE
3751 * behind currently active writes only delays the point where
3752 * the new strategy begins to take effect, so there is no
3753 * benefit in waiting. In this case the minimum restriction
3754 * applies: we don't currently allow concurrent catalog
3755 * updates.
3756 */
3757 case AT_SetStatistics: /* Uses MVCC in getTableAttrs() */
3758 case AT_ClusterOn: /* Uses MVCC in getIndexes() */
3759 case AT_DropCluster: /* Uses MVCC in getIndexes() */
3760 case AT_SetOptions: /* Uses MVCC in getTableAttrs() */
3761 case AT_ResetOptions: /* Uses MVCC in getTableAttrs() */
3762 cmd_lockmode = ShareUpdateExclusiveLock;
3763 break;
3764
3765 case AT_SetLogged:
3766 case AT_SetUnLogged:
3767 cmd_lockmode = AccessExclusiveLock;
3768 break;
3769
3770 case AT_ValidateConstraint: /* Uses MVCC in getConstraints() */
3771 cmd_lockmode = ShareUpdateExclusiveLock;
3772 break;
3773
3774 /*
3775 * Rel options are more complex than first appears. Options
3776 * are set here for tables, views and indexes; for historical
3777 * reasons these can all be used with ALTER TABLE, so we can't
3778 * decide between them using the basic grammar.
3779 */
3780 case AT_SetRelOptions: /* Uses MVCC in getIndexes() and
3781 * getTables() */
3782 case AT_ResetRelOptions: /* Uses MVCC in getIndexes() and
3783 * getTables() */
3784 cmd_lockmode = AlterTableGetRelOptionsLockLevel((List *) cmd->def);
3785 break;
3786
3787 case AT_AttachPartition:
3788 cmd_lockmode = ShareUpdateExclusiveLock;
3789 break;
3790
3791 case AT_DetachPartition:
3792 cmd_lockmode = AccessExclusiveLock;
3793 break;
3794
3795 case AT_CheckNotNull:
3796
3797 /*
3798 * This only examines the table's schema; but lock must be
3799 * strong enough to prevent concurrent DROP NOT NULL.
3800 */
3801 cmd_lockmode = AccessShareLock;
3802 break;
3803
3804 default: /* oops */
3805 elog(ERROR, "unrecognized alter table type: %d",
3806 (int) cmd->subtype);
3807 break;
3808 }
3809
3810 /*
3811 * Take the greatest lockmode from any subcommand
3812 */
3813 if (cmd_lockmode > lockmode)
3814 lockmode = cmd_lockmode;
3815 }
3816
3817 return lockmode;
3818}
3819
3820/*
3821 * ATController provides top level control over the phases.
3822 *
3823 * parsetree is passed in to allow it to be passed to event triggers
3824 * when requested.
3825 */
3826static void
3827ATController(AlterTableStmt *parsetree,
3828 Relation rel, List *cmds, bool recurse, LOCKMODE lockmode)
3829{
3830 List *wqueue = NIL;
3831 ListCell *lcmd;
3832
3833 /* Phase 1: preliminary examination of commands, create work queue */
3834 foreach(lcmd, cmds)
3835 {
3836 AlterTableCmd *cmd = (AlterTableCmd *) lfirst(lcmd);
3837
3838 ATPrepCmd(&wqueue, rel, cmd, recurse, false, lockmode);
3839 }
3840
3841 /* Close the relation, but keep lock until commit */
3842 relation_close(rel, NoLock);
3843
3844 /* Phase 2: update system catalogs */
3845 ATRewriteCatalogs(&wqueue, lockmode);
3846
3847 /* Phase 3: scan/rewrite tables as needed */
3848 ATRewriteTables(parsetree, &wqueue, lockmode);
3849}
3850
3851/*
3852 * ATPrepCmd
3853 *
3854 * Traffic cop for ALTER TABLE Phase 1 operations, including simple
3855 * recursion and permission checks.
3856 *
3857 * Caller must have acquired appropriate lock type on relation already.
3858 * This lock should be held until commit.
3859 */
3860static void
3861ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd,
3862 bool recurse, bool recursing, LOCKMODE lockmode)
3863{
3864 AlteredTableInfo *tab;
3865 int pass = AT_PASS_UNSET;
3866
3867 /* Find or create work queue entry for this table */
3868 tab = ATGetQueueEntry(wqueue, rel);
3869
3870 /*
3871 * Copy the original subcommand for each table. This avoids conflicts
3872 * when different child tables need to make different parse
3873 * transformations (for example, the same column may have different column
3874 * numbers in different children).
3875 */
3876 cmd = copyObject(cmd);
3877
3878 /*
3879 * Do permissions checking, recursion to child tables if needed, and any
3880 * additional phase-1 processing needed.
3881 */
3882 switch (cmd->subtype)
3883 {
3884 case AT_AddColumn: /* ADD COLUMN */
3885 ATSimplePermissions(rel,
3886 ATT_TABLE | ATT_COMPOSITE_TYPE | ATT_FOREIGN_TABLE);
3887 ATPrepAddColumn(wqueue, rel, recurse, recursing, false, cmd,
3888 lockmode);
3889 /* Recursion occurs during execution phase */
3890 pass = AT_PASS_ADD_COL;
3891 break;
3892 case AT_AddColumnToView: /* add column via CREATE OR REPLACE VIEW */
3893 ATSimplePermissions(rel, ATT_VIEW);
3894 ATPrepAddColumn(wqueue, rel, recurse, recursing, true, cmd,
3895 lockmode);
3896 /* Recursion occurs during execution phase */
3897 pass = AT_PASS_ADD_COL;
3898 break;
3899 case AT_ColumnDefault: /* ALTER COLUMN DEFAULT */
3900
3901 /*
3902 * We allow defaults on views so that INSERT into a view can have
3903 * default-ish behavior. This works because the rewriter
3904 * substitutes default values into INSERTs before it expands
3905 * rules.
3906 */
3907 ATSimplePermissions(rel, ATT_TABLE | ATT_VIEW | ATT_FOREIGN_TABLE);
3908 ATSimpleRecursion(wqueue, rel, cmd, recurse, lockmode);
3909 /* No command-specific prep needed */
3910 pass = cmd->def ? AT_PASS_ADD_CONSTR : AT_PASS_DROP;
3911 break;
3912 case AT_AddIdentity:
3913 ATSimplePermissions(rel, ATT_TABLE | ATT_VIEW | ATT_FOREIGN_TABLE);
3914 /* This command never recurses */
3915 pass = AT_PASS_ADD_CONSTR;
3916 break;
3917 case AT_SetIdentity:
3918 ATSimplePermissions(rel, ATT_TABLE | ATT_VIEW | ATT_FOREIGN_TABLE);
3919 /* This command never recurses */
3920 pass = AT_PASS_COL_ATTRS;
3921 break;
3922 case AT_DropIdentity:
3923 ATSimplePermissions(rel, ATT_TABLE | ATT_VIEW | ATT_FOREIGN_TABLE);
3924 /* This command never recurses */
3925 pass = AT_PASS_DROP;
3926 break;
3927 case AT_DropNotNull: /* ALTER COLUMN DROP NOT NULL */
3928 ATSimplePermissions(rel, ATT_TABLE | ATT_FOREIGN_TABLE);
3929 ATPrepDropNotNull(rel, recurse, recursing);
3930 ATSimpleRecursion(wqueue, rel, cmd, recurse, lockmode);
3931 pass = AT_PASS_DROP;
3932 break;
3933 case AT_SetNotNull: /* ALTER COLUMN SET NOT NULL */
3934 ATSimplePermissions(rel, ATT_TABLE | ATT_FOREIGN_TABLE);
3935 /* Need command-specific recursion decision */
3936 ATPrepSetNotNull(wqueue, rel, cmd, recurse, recursing, lockmode);
3937 pass = AT_PASS_COL_ATTRS;
3938 break;
3939 case AT_CheckNotNull: /* check column is already marked NOT NULL */
3940 ATSimplePermissions(rel, ATT_TABLE | ATT_FOREIGN_TABLE);
3941 ATSimpleRecursion(wqueue, rel, cmd, recurse, lockmode);
3942 /* No command-specific prep needed */
3943 pass = AT_PASS_COL_ATTRS;
3944 break;
3945 case AT_SetStatistics: /* ALTER COLUMN SET STATISTICS */
3946 ATSimpleRecursion(wqueue, rel, cmd, recurse, lockmode);
3947 /* Performs own permission checks */
3948 ATPrepSetStatistics(rel, cmd->name, cmd->num, cmd->def, lockmode);
3949 pass = AT_PASS_MISC;
3950 break;
3951 case AT_SetOptions: /* ALTER COLUMN SET ( options ) */
3952 case AT_ResetOptions: /* ALTER COLUMN RESET ( options ) */
3953 ATSimplePermissions(rel, ATT_TABLE | ATT_MATVIEW | ATT_INDEX | ATT_FOREIGN_TABLE);
3954 /* This command never recurses */
3955 pass = AT_PASS_MISC;
3956 break;
3957 case AT_SetStorage: /* ALTER COLUMN SET STORAGE */
3958 ATSimplePermissions(rel, ATT_TABLE | ATT_MATVIEW | ATT_FOREIGN_TABLE);
3959 ATSimpleRecursion(wqueue, rel, cmd, recurse, lockmode);
3960 /* No command-specific prep needed */
3961 pass = AT_PASS_MISC;
3962 break;
3963 case AT_DropColumn: /* DROP COLUMN */
3964 ATSimplePermissions(rel,
3965 ATT_TABLE | ATT_COMPOSITE_TYPE | ATT_FOREIGN_TABLE);
3966 ATPrepDropColumn(wqueue, rel, recurse, recursing, cmd, lockmode);
3967 /* Recursion occurs during execution phase */
3968 pass = AT_PASS_DROP;
3969 break;
3970 case AT_AddIndex: /* ADD INDEX */
3971 ATSimplePermissions(rel, ATT_TABLE);
3972 /* This command never recurses */
3973 /* No command-specific prep needed */
3974 pass = AT_PASS_ADD_INDEX;
3975 break;
3976 case AT_AddConstraint: /* ADD CONSTRAINT */
3977 ATSimplePermissions(rel, ATT_TABLE | ATT_FOREIGN_TABLE);
3978 /* Recursion occurs during execution phase */
3979 /* No command-specific prep needed except saving recurse flag */
3980 if (recurse)
3981 cmd->subtype = AT_AddConstraintRecurse;
3982 pass = AT_PASS_ADD_CONSTR;
3983 break;
3984 case AT_AddIndexConstraint: /* ADD CONSTRAINT USING INDEX */
3985 ATSimplePermissions(rel, ATT_TABLE);
3986 /* This command never recurses */
3987 /* No command-specific prep needed */
3988 pass = AT_PASS_ADD_CONSTR;
3989 break;
3990 case AT_DropConstraint: /* DROP CONSTRAINT */
3991 ATSimplePermissions(rel, ATT_TABLE | ATT_FOREIGN_TABLE);
3992 ATCheckPartitionsNotInUse(rel, lockmode);
3993 /* Other recursion occurs during execution phase */
3994 /* No command-specific prep needed except saving recurse flag */
3995 if (recurse)
3996 cmd->subtype = AT_DropConstraintRecurse;
3997 pass = AT_PASS_DROP;
3998 break;
3999 case AT_AlterColumnType: /* ALTER COLUMN TYPE */
4000 ATSimplePermissions(rel,
4001 ATT_TABLE | ATT_COMPOSITE_TYPE | ATT_FOREIGN_TABLE);
4002 /* Performs own recursion */
4003 ATPrepAlterColumnType(wqueue, tab, rel, recurse, recursing, cmd, lockmode);
4004 pass = AT_PASS_ALTER_TYPE;
4005 break;
4006 case AT_AlterColumnGenericOptions:
4007 ATSimplePermissions(rel, ATT_FOREIGN_TABLE);
4008 /* This command never recurses */
4009 /* No command-specific prep needed */
4010 pass = AT_PASS_MISC;
4011 break;
4012 case AT_ChangeOwner: /* ALTER OWNER */
4013 /* This command never recurses */
4014 /* No command-specific prep needed */
4015 pass = AT_PASS_MISC;
4016 break;
4017 case AT_ClusterOn: /* CLUSTER ON */
4018 case AT_DropCluster: /* SET WITHOUT CLUSTER */
4019 ATSimplePermissions(rel, ATT_TABLE | ATT_MATVIEW);
4020 /* These commands never recurse */
4021 /* No command-specific prep needed */
4022 pass = AT_PASS_MISC;
4023 break;
4024 case AT_SetLogged: /* SET LOGGED */
4025 ATSimplePermissions(rel, ATT_TABLE);
4026 tab->chgPersistence = ATPrepChangePersistence(rel, true);
4027 /* force rewrite if necessary; see comment in ATRewriteTables */
4028 if (tab->chgPersistence)
4029 {
4030 tab->rewrite |= AT_REWRITE_ALTER_PERSISTENCE;
4031 tab->newrelpersistence = RELPERSISTENCE_PERMANENT;
4032 }
4033 pass = AT_PASS_MISC;
4034 break;
4035 case AT_SetUnLogged: /* SET UNLOGGED */
4036 ATSimplePermissions(rel, ATT_TABLE);
4037 tab->chgPersistence = ATPrepChangePersistence(rel, false);
4038 /* force rewrite if necessary; see comment in ATRewriteTables */
4039 if (tab->chgPersistence)
4040 {
4041 tab->rewrite |= AT_REWRITE_ALTER_PERSISTENCE;
4042 tab->newrelpersistence = RELPERSISTENCE_UNLOGGED;
4043 }
4044 pass = AT_PASS_MISC;
4045 break;
4046 case AT_DropOids: /* SET WITHOUT OIDS */
4047 ATSimplePermissions(rel, ATT_TABLE | ATT_FOREIGN_TABLE);
4048 pass = AT_PASS_DROP;
4049 break;
4050 case AT_SetTableSpace: /* SET TABLESPACE */
4051 ATSimplePermissions(rel, ATT_TABLE | ATT_MATVIEW | ATT_INDEX |
4052 ATT_PARTITIONED_INDEX);
4053 /* This command never recurses */
4054 ATPrepSetTableSpace(tab, rel, cmd->name, lockmode);
4055 pass = AT_PASS_MISC; /* doesn't actually matter */
4056 break;
4057 case AT_SetRelOptions: /* SET (...) */
4058 case AT_ResetRelOptions: /* RESET (...) */
4059 case AT_ReplaceRelOptions: /* reset them all, then set just these */
4060 ATSimplePermissions(rel, ATT_TABLE | ATT_VIEW | ATT_MATVIEW | ATT_INDEX);
4061 /* This command never recurses */
4062 /* No command-specific prep needed */
4063 pass = AT_PASS_MISC;
4064 break;
4065 case AT_AddInherit: /* INHERIT */
4066 ATSimplePermissions(rel, ATT_TABLE | ATT_FOREIGN_TABLE);
4067 /* This command never recurses */
4068 ATPrepAddInherit(rel);
4069 pass = AT_PASS_MISC;
4070 break;
4071 case AT_DropInherit: /* NO INHERIT */
4072 ATSimplePermissions(rel, ATT_TABLE | ATT_FOREIGN_TABLE);
4073 /* This command never recurses */
4074 /* No command-specific prep needed */
4075 pass = AT_PASS_MISC;
4076 break;
4077 case AT_AlterConstraint: /* ALTER CONSTRAINT */
4078 ATSimplePermissions(rel, ATT_TABLE);
4079 pass = AT_PASS_MISC;
4080 break;
4081 case AT_ValidateConstraint: /* VALIDATE CONSTRAINT */
4082 ATSimplePermissions(rel, ATT_TABLE | ATT_FOREIGN_TABLE);
4083 /* Recursion occurs during execution phase */
4084 /* No command-specific prep needed except saving recurse flag */
4085 if (recurse)
4086 cmd->subtype = AT_ValidateConstraintRecurse;
4087 pass = AT_PASS_MISC;
4088 break;
4089 case AT_ReplicaIdentity: /* REPLICA IDENTITY ... */
4090 ATSimplePermissions(rel, ATT_TABLE | ATT_MATVIEW);
4091 pass = AT_PASS_MISC;
4092 /* This command never recurses */
4093 /* No command-specific prep needed */
4094 break;
4095 case AT_EnableTrig: /* ENABLE TRIGGER variants */
4096 case AT_EnableAlwaysTrig:
4097 case AT_EnableReplicaTrig:
4098 case AT_EnableTrigAll:
4099 case AT_EnableTrigUser:
4100 case AT_DisableTrig: /* DISABLE TRIGGER variants */
4101 case AT_DisableTrigAll:
4102 case AT_DisableTrigUser:
4103 ATSimplePermissions(rel, ATT_TABLE | ATT_FOREIGN_TABLE);
4104 pass = AT_PASS_MISC;
4105 break;
4106 case AT_EnableRule: /* ENABLE/DISABLE RULE variants */
4107 case AT_EnableAlwaysRule:
4108 case AT_EnableReplicaRule:
4109 case AT_DisableRule:
4110 case AT_AddOf: /* OF */
4111 case AT_DropOf: /* NOT OF */
4112 case AT_EnableRowSecurity:
4113 case AT_DisableRowSecurity:
4114 case AT_ForceRowSecurity:
4115 case AT_NoForceRowSecurity:
4116 ATSimplePermissions(rel, ATT_TABLE);
4117 /* These commands never recurse */
4118 /* No command-specific prep needed */
4119 pass = AT_PASS_MISC;
4120 break;
4121 case AT_GenericOptions:
4122 ATSimplePermissions(rel, ATT_FOREIGN_TABLE);
4123 /* No command-specific prep needed */
4124 pass = AT_PASS_MISC;
4125 break;
4126 case AT_AttachPartition:
4127 ATSimplePermissions(rel, ATT_TABLE | ATT_PARTITIONED_INDEX);
4128 /* No command-specific prep needed */
4129 pass = AT_PASS_MISC;
4130 break;
4131 case AT_DetachPartition:
4132 ATSimplePermissions(rel, ATT_TABLE);
4133 /* No command-specific prep needed */
4134 pass = AT_PASS_MISC;
4135 break;
4136 default: /* oops */
4137 elog(ERROR, "unrecognized alter table type: %d",
4138 (int) cmd->subtype);
4139 pass = AT_PASS_UNSET; /* keep compiler quiet */
4140 break;
4141 }
4142 Assert(pass > AT_PASS_UNSET);
4143
4144 /* Add the subcommand to the appropriate list for phase 2 */
4145 tab->subcmds[pass] = lappend(tab->subcmds[pass], cmd);
4146}
4147
4148/*
4149 * ATRewriteCatalogs
4150 *
4151 * Traffic cop for ALTER TABLE Phase 2 operations. Subcommands are
4152 * dispatched in a "safe" execution order (designed to avoid unnecessary
4153 * conflicts).
4154 */
4155static void
4156ATRewriteCatalogs(List **wqueue, LOCKMODE lockmode)
4157{
4158 int pass;
4159 ListCell *ltab;
4160
4161 /*
4162 * We process all the tables "in parallel", one pass at a time. This is
4163 * needed because we may have to propagate work from one table to another
4164 * (specifically, ALTER TYPE on a foreign key's PK has to dispatch the
4165 * re-adding of the foreign key constraint to the other table). Work can
4166 * only be propagated into later passes, however.
4167 */
4168 for (pass = 0; pass < AT_NUM_PASSES; pass++)
4169 {
4170 /* Go through each table that needs to be processed */
4171 foreach(ltab, *wqueue)
4172 {
4173 AlteredTableInfo *tab = (AlteredTableInfo *) lfirst(ltab);
4174 List *subcmds = tab->subcmds[pass];
4175 Relation rel;
4176 ListCell *lcmd;
4177
4178 if (subcmds == NIL)
4179 continue;
4180
4181 /*
4182 * Appropriate lock was obtained by phase 1, needn't get it again
4183 */
4184 rel = relation_open(tab->relid, NoLock);
4185
4186 foreach(lcmd, subcmds)
4187 ATExecCmd(wqueue, tab, rel,
4188 castNode(AlterTableCmd, lfirst(lcmd)),
4189 lockmode);
4190
4191 /*
4192 * After the ALTER TYPE pass, do cleanup work (this is not done in
4193 * ATExecAlterColumnType since it should be done only once if
4194 * multiple columns of a table are altered).
4195 */
4196 if (pass == AT_PASS_ALTER_TYPE)
4197 ATPostAlterTypeCleanup(wqueue, tab, lockmode);
4198
4199 relation_close(rel, NoLock);
4200 }
4201 }
4202
4203 /* Check to see if a toast table must be added. */
4204 foreach(ltab, *wqueue)
4205 {
4206 AlteredTableInfo *tab = (AlteredTableInfo *) lfirst(ltab);
4207
4208 /*
4209 * If the table is source table of ATTACH PARTITION command, we did
4210 * not modify anything about it that will change its toasting
4211 * requirement, so no need to check.
4212 */
4213 if (((tab->relkind == RELKIND_RELATION ||
4214 tab->relkind == RELKIND_PARTITIONED_TABLE) &&
4215 tab->partition_constraint == NULL) ||
4216 tab->relkind == RELKIND_MATVIEW)
4217 AlterTableCreateToastTable(tab->relid, (Datum) 0, lockmode);
4218 }
4219}
4220
4221/*
4222 * ATExecCmd: dispatch a subcommand to appropriate execution routine
4223 */
4224static void
4225ATExecCmd(List **wqueue, AlteredTableInfo *tab, Relation rel,
4226 AlterTableCmd *cmd, LOCKMODE lockmode)
4227{
4228 ObjectAddress address = InvalidObjectAddress;
4229
4230 switch (cmd->subtype)
4231 {
4232 case AT_AddColumn: /* ADD COLUMN */
4233 case AT_AddColumnToView: /* add column via CREATE OR REPLACE VIEW */
4234 address = ATExecAddColumn(wqueue, tab, rel, (ColumnDef *) cmd->def,
4235 false, false,
4236 cmd->missing_ok, lockmode);
4237 break;
4238 case AT_AddColumnRecurse:
4239 address = ATExecAddColumn(wqueue, tab, rel, (ColumnDef *) cmd->def,
4240 true, false,
4241 cmd->missing_ok, lockmode);
4242 break;
4243 case AT_ColumnDefault: /* ALTER COLUMN DEFAULT */
4244 address = ATExecColumnDefault(rel, cmd->name, cmd->def, lockmode);
4245 break;
4246 case AT_AddIdentity:
4247 address = ATExecAddIdentity(rel, cmd->name, cmd->def, lockmode);
4248 break;
4249 case AT_SetIdentity:
4250 address = ATExecSetIdentity(rel, cmd->name, cmd->def, lockmode);
4251 break;
4252 case AT_DropIdentity:
4253 address = ATExecDropIdentity(rel, cmd->name, cmd->missing_ok, lockmode);
4254 break;
4255 case AT_DropNotNull: /* ALTER COLUMN DROP NOT NULL */
4256 address = ATExecDropNotNull(rel, cmd->name, lockmode);
4257 break;
4258 case AT_SetNotNull: /* ALTER COLUMN SET NOT NULL */
4259 address = ATExecSetNotNull(tab, rel, cmd->name, lockmode);
4260 break;
4261 case AT_CheckNotNull: /* check column is already marked NOT NULL */
4262 ATExecCheckNotNull(tab, rel, cmd->name, lockmode);
4263 break;
4264 case AT_SetStatistics: /* ALTER COLUMN SET STATISTICS */
4265 address = ATExecSetStatistics(rel, cmd->name, cmd->num, cmd->def, lockmode);
4266 break;
4267 case AT_SetOptions: /* ALTER COLUMN SET ( options ) */
4268 address = ATExecSetOptions(rel, cmd->name, cmd->def, false, lockmode);
4269 break;
4270 case AT_ResetOptions: /* ALTER COLUMN RESET ( options ) */
4271 address = ATExecSetOptions(rel, cmd->name, cmd->def, true, lockmode);
4272 break;
4273 case AT_SetStorage: /* ALTER COLUMN SET STORAGE */
4274 address = ATExecSetStorage(rel, cmd->name, cmd->def, lockmode);
4275 break;
4276 case AT_DropColumn: /* DROP COLUMN */
4277 address = ATExecDropColumn(wqueue, rel, cmd->name,
4278 cmd->behavior, false, false,
4279 cmd->missing_ok, lockmode);
4280 break;
4281 case AT_DropColumnRecurse: /* DROP COLUMN with recursion */
4282 address = ATExecDropColumn(wqueue, rel, cmd->name,
4283 cmd->behavior, true, false,
4284 cmd->missing_ok, lockmode);
4285 break;
4286 case AT_AddIndex: /* ADD INDEX */
4287 address = ATExecAddIndex(tab, rel, (IndexStmt *) cmd->def, false,
4288 lockmode);
4289 break;
4290 case AT_ReAddIndex: /* ADD INDEX */
4291 address = ATExecAddIndex(tab, rel, (IndexStmt *) cmd->def, true,
4292 lockmode);
4293 break;
4294 case AT_AddConstraint: /* ADD CONSTRAINT */
4295 address =
4296 ATExecAddConstraint(wqueue, tab, rel, (Constraint *) cmd->def,
4297 false, false, lockmode);
4298 break;
4299 case AT_AddConstraintRecurse: /* ADD CONSTRAINT with recursion */
4300 address =
4301 ATExecAddConstraint(wqueue, tab, rel, (Constraint *) cmd->def,
4302 true, false, lockmode);
4303 break;
4304 case AT_ReAddConstraint: /* Re-add pre-existing check constraint */
4305 address =
4306 ATExecAddConstraint(wqueue, tab, rel, (Constraint *) cmd->def,
4307 true, true, lockmode);
4308 break;
4309 case AT_ReAddDomainConstraint: /* Re-add pre-existing domain check
4310 * constraint */
4311 address =
4312 AlterDomainAddConstraint(((AlterDomainStmt *) cmd->def)->typeName,
4313 ((AlterDomainStmt *) cmd->def)->def,
4314 NULL);
4315 break;
4316 case AT_ReAddComment: /* Re-add existing comment */
4317 address = CommentObject((CommentStmt *) cmd->def);
4318 break;
4319 case AT_AddIndexConstraint: /* ADD CONSTRAINT USING INDEX */
4320 address = ATExecAddIndexConstraint(tab, rel, (IndexStmt *) cmd->def,
4321 lockmode);
4322 break;
4323 case AT_AlterConstraint: /* ALTER CONSTRAINT */
4324 address = ATExecAlterConstraint(rel, cmd, false, false, lockmode);
4325 break;
4326 case AT_ValidateConstraint: /* VALIDATE CONSTRAINT */
4327 address = ATExecValidateConstraint(rel, cmd->name, false, false,
4328 lockmode);
4329 break;
4330 case AT_ValidateConstraintRecurse: /* VALIDATE CONSTRAINT with
4331 * recursion */
4332 address = ATExecValidateConstraint(rel, cmd->name, true, false,
4333 lockmode);
4334 break;
4335 case AT_DropConstraint: /* DROP CONSTRAINT */
4336 ATExecDropConstraint(rel, cmd->name, cmd->behavior,
4337 false, false,
4338 cmd->missing_ok, lockmode);
4339 break;
4340 case AT_DropConstraintRecurse: /* DROP CONSTRAINT with recursion */
4341 ATExecDropConstraint(rel, cmd->name, cmd->behavior,
4342 true, false,
4343 cmd->missing_ok, lockmode);
4344 break;
4345 case AT_AlterColumnType: /* ALTER COLUMN TYPE */
4346 address = ATExecAlterColumnType(tab, rel, cmd, lockmode);
4347 break;
4348 case AT_AlterColumnGenericOptions: /* ALTER COLUMN OPTIONS */
4349 address =
4350 ATExecAlterColumnGenericOptions(rel, cmd->name,
4351 (List *) cmd->def, lockmode);
4352 break;
4353 case AT_ChangeOwner: /* ALTER OWNER */
4354 ATExecChangeOwner(RelationGetRelid(rel),
4355 get_rolespec_oid(cmd->newowner, false),
4356 false, lockmode);
4357 break;
4358 case AT_ClusterOn: /* CLUSTER ON */
4359 address = ATExecClusterOn(rel, cmd->name, lockmode);
4360 break;
4361 case AT_DropCluster: /* SET WITHOUT CLUSTER */
4362 ATExecDropCluster(rel, lockmode);
4363 break;
4364 case AT_SetLogged: /* SET LOGGED */
4365 case AT_SetUnLogged: /* SET UNLOGGED */
4366 break;
4367 case AT_DropOids: /* SET WITHOUT OIDS */
4368 /* nothing to do here, oid columns don't exist anymore */
4369 break;
4370 case AT_SetTableSpace: /* SET TABLESPACE */
4371
4372 /*
4373 * Only do this for partitioned tables and indexes, for which this
4374 * is just a catalog change. Other relation types which have
4375 * storage are handled by Phase 3.
4376 */
4377 if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ||
4378 rel->rd_rel->relkind == RELKIND_PARTITIONED_INDEX)
4379 ATExecSetTableSpaceNoStorage(rel, tab->newTableSpace);
4380
4381 break;
4382 case AT_SetRelOptions: /* SET (...) */
4383 case AT_ResetRelOptions: /* RESET (...) */
4384 case AT_ReplaceRelOptions: /* replace entire option list */
4385 ATExecSetRelOptions(rel, (List *) cmd->def, cmd->subtype, lockmode);
4386 break;
4387 case AT_EnableTrig: /* ENABLE TRIGGER name */
4388 ATExecEnableDisableTrigger(rel, cmd->name,
4389 TRIGGER_FIRES_ON_ORIGIN, false, lockmode);
4390 break;
4391 case AT_EnableAlwaysTrig: /* ENABLE ALWAYS TRIGGER name */
4392 ATExecEnableDisableTrigger(rel, cmd->name,
4393 TRIGGER_FIRES_ALWAYS, false, lockmode);
4394 break;
4395 case AT_EnableReplicaTrig: /* ENABLE REPLICA TRIGGER name */
4396 ATExecEnableDisableTrigger(rel, cmd->name,
4397 TRIGGER_FIRES_ON_REPLICA, false, lockmode);
4398 break;
4399 case AT_DisableTrig: /* DISABLE TRIGGER name */
4400 ATExecEnableDisableTrigger(rel, cmd->name,
4401 TRIGGER_DISABLED, false, lockmode);
4402 break;
4403 case AT_EnableTrigAll: /* ENABLE TRIGGER ALL */
4404 ATExecEnableDisableTrigger(rel, NULL,
4405 TRIGGER_FIRES_ON_ORIGIN, false, lockmode);
4406 break;
4407 case AT_DisableTrigAll: /* DISABLE TRIGGER ALL */
4408 ATExecEnableDisableTrigger(rel, NULL,
4409 TRIGGER_DISABLED, false, lockmode);
4410 break;
4411 case AT_EnableTrigUser: /* ENABLE TRIGGER USER */
4412 ATExecEnableDisableTrigger(rel, NULL,
4413 TRIGGER_FIRES_ON_ORIGIN, true, lockmode);
4414 break;
4415 case AT_DisableTrigUser: /* DISABLE TRIGGER USER */
4416 ATExecEnableDisableTrigger(rel, NULL,
4417 TRIGGER_DISABLED, true, lockmode);
4418 break;
4419
4420 case AT_EnableRule: /* ENABLE RULE name */
4421 ATExecEnableDisableRule(rel, cmd->name,
4422 RULE_FIRES_ON_ORIGIN, lockmode);
4423 break;
4424 case AT_EnableAlwaysRule: /* ENABLE ALWAYS RULE name */
4425 ATExecEnableDisableRule(rel, cmd->name,
4426 RULE_FIRES_ALWAYS, lockmode);
4427 break;
4428 case AT_EnableReplicaRule: /* ENABLE REPLICA RULE name */
4429 ATExecEnableDisableRule(rel, cmd->name,
4430 RULE_FIRES_ON_REPLICA, lockmode);
4431 break;
4432 case AT_DisableRule: /* DISABLE RULE name */
4433 ATExecEnableDisableRule(rel, cmd->name,
4434 RULE_DISABLED, lockmode);
4435 break;
4436
4437 case AT_AddInherit:
4438 address = ATExecAddInherit(rel, (RangeVar *) cmd->def, lockmode);
4439 break;
4440 case AT_DropInherit:
4441 address = ATExecDropInherit(rel, (RangeVar *) cmd->def, lockmode);
4442 break;
4443 case AT_AddOf:
4444 address = ATExecAddOf(rel, (TypeName *) cmd->def, lockmode);
4445 break;
4446 case AT_DropOf:
4447 ATExecDropOf(rel, lockmode);
4448 break;
4449 case AT_ReplicaIdentity:
4450 ATExecReplicaIdentity(rel, (ReplicaIdentityStmt *) cmd->def, lockmode);
4451 break;
4452 case AT_EnableRowSecurity:
4453 ATExecEnableRowSecurity(rel);
4454 break;
4455 case AT_DisableRowSecurity:
4456 ATExecDisableRowSecurity(rel);
4457 break;
4458 case AT_ForceRowSecurity:
4459 ATExecForceNoForceRowSecurity(rel, true);
4460 break;
4461 case AT_NoForceRowSecurity:
4462 ATExecForceNoForceRowSecurity(rel, false);
4463 break;
4464 case AT_GenericOptions:
4465 ATExecGenericOptions(rel, (List *) cmd->def);
4466 break;
4467 case AT_AttachPartition:
4468 if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
4469 ATExecAttachPartition(wqueue, rel, (PartitionCmd *) cmd->def);
4470 else
4471 ATExecAttachPartitionIdx(wqueue, rel,
4472 ((PartitionCmd *) cmd->def)->name);
4473 break;
4474 case AT_DetachPartition:
4475 /* ATPrepCmd ensures it must be a table */
4476 Assert(rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE);
4477 ATExecDetachPartition(rel, ((PartitionCmd *) cmd->def)->name);
4478 break;
4479 default: /* oops */
4480 elog(ERROR, "unrecognized alter table type: %d",
4481 (int) cmd->subtype);
4482 break;
4483 }
4484
4485 /*
4486 * Report the subcommand to interested event triggers.
4487 */
4488 EventTriggerCollectAlterTableSubcmd((Node *) cmd, address);
4489
4490 /*
4491 * Bump the command counter to ensure the next subcommand in the sequence
4492 * can see the changes so far
4493 */
4494 CommandCounterIncrement();
4495}
4496
4497/*
4498 * ATRewriteTables: ALTER TABLE phase 3
4499 */
4500static void
4501ATRewriteTables(AlterTableStmt *parsetree, List **wqueue, LOCKMODE lockmode)
4502{
4503 ListCell *ltab;
4504
4505 /* Go through each table that needs to be checked or rewritten */
4506 foreach(ltab, *wqueue)
4507 {
4508 AlteredTableInfo *tab = (AlteredTableInfo *) lfirst(ltab);
4509
4510 /* Relations without storage may be ignored here */
4511 if (!RELKIND_HAS_STORAGE(tab->relkind))
4512 continue;
4513
4514 /*
4515 * If we change column data types or add/remove OIDs, the operation
4516 * has to be propagated to tables that use this table's rowtype as a
4517 * column type. tab->newvals will also be non-NULL in the case where
4518 * we're adding a column with a default. We choose to forbid that
4519 * case as well, since composite types might eventually support
4520 * defaults.
4521 *
4522 * (Eventually we'll probably need to check for composite type
4523 * dependencies even when we're just scanning the table without a
4524 * rewrite, but at the moment a composite type does not enforce any
4525 * constraints, so it's not necessary/appropriate to enforce them just
4526 * during ALTER.)
4527 */
4528 if (tab->newvals != NIL || tab->rewrite > 0)
4529 {
4530 Relation rel;
4531
4532 rel = table_open(tab->relid, NoLock);
4533 find_composite_type_dependencies(rel->rd_rel->reltype, rel, NULL);
4534 table_close(rel, NoLock);
4535 }
4536
4537 /*
4538 * We only need to rewrite the table if at least one column needs to
4539 * be recomputed, we are adding/removing the OID column, or we are
4540 * changing its persistence.
4541 *
4542 * There are two reasons for requiring a rewrite when changing
4543 * persistence: on one hand, we need to ensure that the buffers
4544 * belonging to each of the two relations are marked with or without
4545 * BM_PERMANENT properly. On the other hand, since rewriting creates
4546 * and assigns a new relfilenode, we automatically create or drop an
4547 * init fork for the relation as appropriate.
4548 */
4549 if (tab->rewrite > 0)
4550 {
4551 /* Build a temporary relation and copy data */
4552 Relation OldHeap;
4553 Oid OIDNewHeap;
4554 Oid NewTableSpace;
4555 char persistence;
4556
4557 OldHeap = table_open(tab->relid, NoLock);
4558
4559 /*
4560 * We don't support rewriting of system catalogs; there are too
4561 * many corner cases and too little benefit. In particular this
4562 * is certainly not going to work for mapped catalogs.
4563 */
4564 if (IsSystemRelation(OldHeap))
4565 ereport(ERROR,
4566 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4567 errmsg("cannot rewrite system relation \"%s\"",
4568 RelationGetRelationName(OldHeap))));
4569
4570 if (RelationIsUsedAsCatalogTable(OldHeap))
4571 ereport(ERROR,
4572 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4573 errmsg("cannot rewrite table \"%s\" used as a catalog table",
4574 RelationGetRelationName(OldHeap))));
4575
4576 /*
4577 * Don't allow rewrite on temp tables of other backends ... their
4578 * local buffer manager is not going to cope.
4579 */
4580 if (RELATION_IS_OTHER_TEMP(OldHeap))
4581 ereport(ERROR,
4582 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
4583 errmsg("cannot rewrite temporary tables of other sessions")));
4584
4585 /*
4586 * Select destination tablespace (same as original unless user
4587 * requested a change)
4588 */
4589 if (tab->newTableSpace)
4590 NewTableSpace = tab->newTableSpace;
4591 else
4592 NewTableSpace = OldHeap->rd_rel->reltablespace;
4593
4594 /*
4595 * Select persistence of transient table (same as original unless
4596 * user requested a change)
4597 */
4598 persistence = tab->chgPersistence ?
4599 tab->newrelpersistence : OldHeap->rd_rel->relpersistence;
4600
4601 table_close(OldHeap, NoLock);
4602
4603 /*
4604 * Fire off an Event Trigger now, before actually rewriting the
4605 * table.
4606 *
4607 * We don't support Event Trigger for nested commands anywhere,
4608 * here included, and parsetree is given NULL when coming from
4609 * AlterTableInternal.
4610 *
4611 * And fire it only once.
4612 */
4613 if (parsetree)
4614 EventTriggerTableRewrite((Node *) parsetree,
4615 tab->relid,
4616 tab->rewrite);
4617
4618 /*
4619 * Create transient table that will receive the modified data.
4620 *
4621 * Ensure it is marked correctly as logged or unlogged. We have
4622 * to do this here so that buffers for the new relfilenode will
4623 * have the right persistence set, and at the same time ensure
4624 * that the original filenode's buffers will get read in with the
4625 * correct setting (i.e. the original one). Otherwise a rollback
4626 * after the rewrite would possibly result with buffers for the
4627 * original filenode having the wrong persistence setting.
4628 *
4629 * NB: This relies on swap_relation_files() also swapping the
4630 * persistence. That wouldn't work for pg_class, but that can't be
4631 * unlogged anyway.
4632 */
4633 OIDNewHeap = make_new_heap(tab->relid, NewTableSpace, persistence,
4634 lockmode);
4635
4636 /*
4637 * Copy the heap data into the new table with the desired
4638 * modifications, and test the current data within the table
4639 * against new constraints generated by ALTER TABLE commands.
4640 */
4641 ATRewriteTable(tab, OIDNewHeap, lockmode);
4642
4643 /*
4644 * Swap the physical files of the old and new heaps, then rebuild
4645 * indexes and discard the old heap. We can use RecentXmin for
4646 * the table's new relfrozenxid because we rewrote all the tuples
4647 * in ATRewriteTable, so no older Xid remains in the table. Also,
4648 * we never try to swap toast tables by content, since we have no
4649 * interest in letting this code work on system catalogs.
4650 */
4651 finish_heap_swap(tab->relid, OIDNewHeap,
4652 false, false, true,
4653 !OidIsValid(tab->newTableSpace),
4654 RecentXmin,
4655 ReadNextMultiXactId(),
4656 persistence);
4657 }
4658 else
4659 {
4660 /*
4661 * If required, test the current data within the table against new
4662 * constraints generated by ALTER TABLE commands, but don't
4663 * rebuild data.
4664 */
4665 if (tab->constraints != NIL || tab->verify_new_notnull ||
4666 tab->partition_constraint != NULL)
4667 ATRewriteTable(tab, InvalidOid, lockmode);
4668
4669 /*
4670 * If we had SET TABLESPACE but no reason to reconstruct tuples,
4671 * just do a block-by-block copy.
4672 */
4673 if (tab->newTableSpace)
4674 ATExecSetTableSpace(tab->relid, tab->newTableSpace, lockmode);
4675 }
4676 }
4677
4678 /*
4679 * Foreign key constraints are checked in a final pass, since (a) it's
4680 * generally best to examine each one separately, and (b) it's at least
4681 * theoretically possible that we have changed both relations of the
4682 * foreign key, and we'd better have finished both rewrites before we try
4683 * to read the tables.
4684 */
4685 foreach(ltab, *wqueue)
4686 {
4687 AlteredTableInfo *tab = (AlteredTableInfo *) lfirst(ltab);
4688 Relation rel = NULL;
4689 ListCell *lcon;
4690
4691 /* Relations without storage may be ignored here too */
4692 if (!RELKIND_HAS_STORAGE(tab->relkind))
4693 continue;
4694
4695 foreach(lcon, tab->constraints)
4696 {
4697 NewConstraint *con = lfirst(lcon);
4698
4699 if (con->contype == CONSTR_FOREIGN)
4700 {
4701 Constraint *fkconstraint = (Constraint *) con->qual;
4702 Relation refrel;
4703
4704 if (rel == NULL)
4705 {
4706 /* Long since locked, no need for another */
4707 rel = table_open(tab->relid, NoLock);
4708 }
4709
4710 refrel = table_open(con->refrelid, RowShareLock);
4711
4712 validateForeignKeyConstraint(fkconstraint->conname, rel, refrel,
4713 con->refindid,
4714 con->conid);
4715
4716 /*
4717 * No need to mark the constraint row as validated, we did
4718 * that when we inserted the row earlier.
4719 */
4720
4721 table_close(refrel, NoLock);
4722 }
4723 }
4724
4725 if (rel)
4726 table_close(rel, NoLock);
4727 }
4728}
4729
4730/*
4731 * ATRewriteTable: scan or rewrite one table
4732 *
4733 * OIDNewHeap is InvalidOid if we don't need to rewrite
4734 */
4735static void
4736ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap, LOCKMODE lockmode)
4737{
4738 Relation oldrel;
4739 Relation newrel;
4740 TupleDesc oldTupDesc;
4741 TupleDesc newTupDesc;
4742 bool needscan = false;
4743 List *notnull_attrs;
4744 int i;
4745 ListCell *l;
4746 EState *estate;
4747 CommandId mycid;
4748 BulkInsertState bistate;
4749 int ti_options;
4750 ExprState *partqualstate = NULL;
4751
4752 /*
4753 * Open the relation(s). We have surely already locked the existing
4754 * table.
4755 */
4756 oldrel = table_open(tab->relid, NoLock);
4757 oldTupDesc = tab->oldDesc;
4758 newTupDesc = RelationGetDescr(oldrel); /* includes all mods */
4759
4760 if (OidIsValid(OIDNewHeap))
4761 newrel = table_open(OIDNewHeap, lockmode);
4762 else
4763 newrel = NULL;
4764
4765 /*
4766 * Prepare a BulkInsertState and options for table_tuple_insert. Because
4767 * we're building a new heap, we can skip WAL-logging and fsync it to disk
4768 * at the end instead (unless WAL-logging is required for archiving or
4769 * streaming replication). The FSM is empty too, so don't bother using it.
4770 */
4771 if (newrel)
4772 {
4773 mycid = GetCurrentCommandId(true);
4774 bistate = GetBulkInsertState();
4775
4776 ti_options = TABLE_INSERT_SKIP_FSM;
4777 if (!XLogIsNeeded())
4778 ti_options |= TABLE_INSERT_SKIP_WAL;
4779 }
4780 else
4781 {
4782 /* keep compiler quiet about using these uninitialized */
4783 mycid = 0;
4784 bistate = NULL;
4785 ti_options = 0;
4786 }
4787
4788 /*
4789 * Generate the constraint and default execution states
4790 */
4791
4792 estate = CreateExecutorState();
4793
4794 /* Build the needed expression execution states */
4795 foreach(l, tab->constraints)
4796 {
4797 NewConstraint *con = lfirst(l);
4798
4799 switch (con->contype)
4800 {
4801 case CONSTR_CHECK:
4802 needscan = true;
4803 con->qualstate = ExecPrepareExpr((Expr *) con->qual, estate);
4804 break;
4805 case CONSTR_FOREIGN:
4806 /* Nothing to do here */
4807 break;
4808 default:
4809 elog(ERROR, "unrecognized constraint type: %d",
4810 (int) con->contype);
4811 }
4812 }
4813
4814 /* Build expression execution states for partition check quals */
4815 if (tab->partition_constraint)
4816 {
4817 needscan = true;
4818 partqualstate = ExecPrepareExpr(tab->partition_constraint, estate);
4819 }
4820
4821 foreach(l, tab->newvals)
4822 {
4823 NewColumnValue *ex = lfirst(l);
4824
4825 /* expr already planned */
4826 ex->exprstate = ExecInitExpr((Expr *) ex->expr, NULL);
4827 }
4828
4829 notnull_attrs = NIL;
4830 if (newrel || tab->verify_new_notnull)
4831 {
4832 /*
4833 * If we are rebuilding the tuples OR if we added any new but not
4834 * verified NOT NULL constraints, check all not-null constraints. This
4835 * is a bit of overkill but it minimizes risk of bugs, and
4836 * heap_attisnull is a pretty cheap test anyway.
4837 */
4838 for (i = 0; i < newTupDesc->natts; i++)
4839 {
4840 Form_pg_attribute attr = TupleDescAttr(newTupDesc, i);
4841
4842 if (attr->attnotnull && !attr->attisdropped)
4843 notnull_attrs = lappend_int(notnull_attrs, i);
4844 }
4845 if (notnull_attrs)
4846 needscan = true;
4847 }
4848
4849 if (newrel || needscan)
4850 {
4851 ExprContext *econtext;
4852 TupleTableSlot *oldslot;
4853 TupleTableSlot *newslot;
4854 TableScanDesc scan;
4855 MemoryContext oldCxt;
4856 List *dropped_attrs = NIL;
4857 ListCell *lc;
4858 Snapshot snapshot;
4859
4860 if (newrel)
4861 ereport(DEBUG1,
4862 (errmsg("rewriting table \"%s\"",
4863 RelationGetRelationName(oldrel))));
4864 else
4865 ereport(DEBUG1,
4866 (errmsg("verifying table \"%s\"",
4867 RelationGetRelationName(oldrel))));
4868
4869 if (newrel)
4870 {
4871 /*
4872 * All predicate locks on the tuples or pages are about to be made
4873 * invalid, because we move tuples around. Promote them to
4874 * relation locks.
4875 */
4876 TransferPredicateLocksToHeapRelation(oldrel);
4877 }
4878
4879 econtext = GetPerTupleExprContext(estate);
4880
4881 /*
4882 * Create necessary tuple slots. When rewriting, two slots are needed,
4883 * otherwise one suffices. In the case where one slot suffices, we
4884 * need to use the new tuple descriptor, otherwise some constraints
4885 * can't be evaluated. Note that even when the tuple layout is the
4886 * same and no rewrite is required, the tupDescs might not be
4887 * (consider ADD COLUMN without a default).
4888 */
4889 if (tab->rewrite)
4890 {
4891 Assert(newrel != NULL);
4892 oldslot = MakeSingleTupleTableSlot(oldTupDesc,
4893 table_slot_callbacks(oldrel));
4894 newslot = MakeSingleTupleTableSlot(newTupDesc,
4895 table_slot_callbacks(newrel));
4896 }
4897 else
4898 {
4899 oldslot = MakeSingleTupleTableSlot(newTupDesc,
4900 table_slot_callbacks(oldrel));
4901 newslot = NULL;
4902 }
4903
4904 /*
4905 * Any attributes that are dropped according to the new tuple
4906 * descriptor can be set to NULL. We precompute the list of dropped
4907 * attributes to avoid needing to do so in the per-tuple loop.
4908 */
4909 for (i = 0; i < newTupDesc->natts; i++)
4910 {
4911 if (TupleDescAttr(newTupDesc, i)->attisdropped)
4912 dropped_attrs = lappend_int(dropped_attrs, i);
4913 }
4914
4915 /*
4916 * Scan through the rows, generating a new row if needed and then
4917 * checking all the constraints.
4918 */
4919 snapshot = RegisterSnapshot(GetLatestSnapshot());
4920 scan = table_beginscan(oldrel, snapshot, 0, NULL);
4921
4922 /*
4923 * Switch to per-tuple memory context and reset it for each tuple
4924 * produced, so we don't leak memory.
4925 */
4926 oldCxt = MemoryContextSwitchTo(GetPerTupleMemoryContext(estate));
4927
4928 while (table_scan_getnextslot(scan, ForwardScanDirection, oldslot))
4929 {
4930 TupleTableSlot *insertslot;
4931
4932 if (tab->rewrite > 0)
4933 {
4934 /* Extract data from old tuple */
4935 slot_getallattrs(oldslot);
4936 ExecClearTuple(newslot);
4937
4938 /* copy attributes */
4939 memcpy(newslot->tts_values, oldslot->tts_values,
4940 sizeof(Datum) * oldslot->tts_nvalid);
4941 memcpy(newslot->tts_isnull, oldslot->tts_isnull,
4942 sizeof(bool) * oldslot->tts_nvalid);
4943
4944 /* Set dropped attributes to null in new tuple */
4945 foreach(lc, dropped_attrs)
4946 newslot->tts_isnull[lfirst_int(lc)] = true;
4947
4948 /*
4949 * Process supplied expressions to replace selected columns.
4950 * Expression inputs come from the old tuple.
4951 */
4952 econtext->ecxt_scantuple = oldslot;
4953
4954 foreach(l, tab->newvals)
4955 {
4956 NewColumnValue *ex = lfirst(l);
4957
4958 newslot->tts_values[ex->attnum - 1]
4959 = ExecEvalExpr(ex->exprstate,
4960 econtext,
4961 &newslot->tts_isnull[ex->attnum - 1]);
4962 }
4963
4964 ExecStoreVirtualTuple(newslot);
4965
4966 /*
4967 * Constraints might reference the tableoid column, so
4968 * initialize t_tableOid before evaluating them.
4969 */
4970 newslot->tts_tableOid = RelationGetRelid(oldrel);
4971 insertslot = newslot;
4972 }
4973 else
4974 {
4975 /*
4976 * If there's no rewrite, old and new table are guaranteed to
4977 * have the same AM, so we can just use the old slot to verify
4978 * new constraints etc.
4979 */
4980 insertslot = oldslot;
4981 }
4982
4983 /* Now check any constraints on the possibly-changed tuple */
4984 econtext->ecxt_scantuple = insertslot;
4985
4986 foreach(l, notnull_attrs)
4987 {
4988 int attn = lfirst_int(l);
4989
4990 if (slot_attisnull(insertslot, attn + 1))
4991 {
4992 Form_pg_attribute attr = TupleDescAttr(newTupDesc, attn);
4993
4994 ereport(ERROR,
4995 (errcode(ERRCODE_NOT_NULL_VIOLATION),
4996 errmsg("column \"%s\" contains null values",
4997 NameStr(attr->attname)),
4998 errtablecol(oldrel, attn + 1)));
4999 }
5000 }
5001
5002 foreach(l, tab->constraints)
5003 {
5004 NewConstraint *con = lfirst(l);
5005
5006 switch (con->contype)
5007 {
5008 case CONSTR_CHECK:
5009 if (!ExecCheck(con->qualstate, econtext))
5010 ereport(ERROR,
5011 (errcode(ERRCODE_CHECK_VIOLATION),
5012 errmsg("check constraint \"%s\" is violated by some row",
5013 con->name),
5014 errtableconstraint(oldrel, con->name)));
5015 break;
5016 case CONSTR_FOREIGN:
5017 /* Nothing to do here */
5018 break;
5019 default:
5020 elog(ERROR, "unrecognized constraint type: %d",
5021 (int) con->contype);
5022 }
5023 }
5024
5025 if (partqualstate && !ExecCheck(partqualstate, econtext))
5026 {
5027 if (tab->validate_default)
5028 ereport(ERROR,
5029 (errcode(ERRCODE_CHECK_VIOLATION),
5030 errmsg("updated partition constraint for default partition would be violated by some row")));
5031 else
5032 ereport(ERROR,
5033 (errcode(ERRCODE_CHECK_VIOLATION),
5034 errmsg("partition constraint is violated by some row")));
5035 }
5036
5037 /* Write the tuple out to the new relation */
5038 if (newrel)
5039 table_tuple_insert(newrel, insertslot, mycid,
5040 ti_options, bistate);
5041
5042 ResetExprContext(econtext);
5043
5044 CHECK_FOR_INTERRUPTS();
5045 }
5046
5047 MemoryContextSwitchTo(oldCxt);
5048 table_endscan(scan);
5049 UnregisterSnapshot(snapshot);
5050
5051 ExecDropSingleTupleTableSlot(oldslot);
5052 if (newslot)
5053 ExecDropSingleTupleTableSlot(newslot);
5054 }
5055
5056 FreeExecutorState(estate);
5057
5058 table_close(oldrel, NoLock);
5059 if (newrel)
5060 {
5061 FreeBulkInsertState(bistate);
5062
5063 table_finish_bulk_insert(newrel, ti_options);
5064
5065 table_close(newrel, NoLock);
5066 }
5067}
5068
5069/*
5070 * ATGetQueueEntry: find or create an entry in the ALTER TABLE work queue
5071 */
5072static AlteredTableInfo *
5073ATGetQueueEntry(List **wqueue, Relation rel)
5074{
5075 Oid relid = RelationGetRelid(rel);
5076 AlteredTableInfo *tab;
5077 ListCell *ltab;
5078
5079 foreach(ltab, *wqueue)
5080 {
5081 tab = (AlteredTableInfo *) lfirst(ltab);
5082 if (tab->relid == relid)
5083 return tab;
5084 }
5085
5086 /*
5087 * Not there, so add it. Note that we make a copy of the relation's
5088 * existing descriptor before anything interesting can happen to it.
5089 */
5090 tab = (AlteredTableInfo *) palloc0(sizeof(AlteredTableInfo));
5091 tab->relid = relid;
5092 tab->relkind = rel->rd_rel->relkind;
5093 tab->oldDesc = CreateTupleDescCopyConstr(RelationGetDescr(rel));
5094 tab->newrelpersistence = RELPERSISTENCE_PERMANENT;
5095 tab->chgPersistence = false;
5096
5097 *wqueue = lappend(*wqueue, tab);
5098
5099 return tab;
5100}
5101
5102/*
5103 * ATSimplePermissions
5104 *
5105 * - Ensure that it is a relation (or possibly a view)
5106 * - Ensure this user is the owner
5107 * - Ensure that it is not a system table
5108 */
5109static void
5110ATSimplePermissions(Relation rel, int allowed_targets)
5111{
5112 int actual_target;
5113
5114 switch (rel->rd_rel->relkind)
5115 {
5116 case RELKIND_RELATION:
5117 case RELKIND_PARTITIONED_TABLE:
5118 actual_target = ATT_TABLE;
5119 break;
5120 case RELKIND_VIEW:
5121 actual_target = ATT_VIEW;
5122 break;
5123 case RELKIND_MATVIEW:
5124 actual_target = ATT_MATVIEW;
5125 break;
5126 case RELKIND_INDEX:
5127 actual_target = ATT_INDEX;
5128 break;
5129 case RELKIND_PARTITIONED_INDEX:
5130 actual_target = ATT_PARTITIONED_INDEX;
5131 break;
5132 case RELKIND_COMPOSITE_TYPE:
5133 actual_target = ATT_COMPOSITE_TYPE;
5134 break;
5135 case RELKIND_FOREIGN_TABLE:
5136 actual_target = ATT_FOREIGN_TABLE;
5137 break;
5138 default:
5139 actual_target = 0;
5140 break;
5141 }
5142
5143 /* Wrong target type? */
5144 if ((actual_target & allowed_targets) == 0)
5145 ATWrongRelkindError(rel, allowed_targets);
5146
5147 /* Permissions checks */
5148 if (!pg_class_ownercheck(RelationGetRelid(rel), GetUserId()))
5149 aclcheck_error(ACLCHECK_NOT_OWNER, get_relkind_objtype(rel->rd_rel->relkind),
5150 RelationGetRelationName(rel));
5151
5152 if (!allowSystemTableMods && IsSystemRelation(rel))
5153 ereport(ERROR,
5154 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
5155 errmsg("permission denied: \"%s\" is a system catalog",
5156 RelationGetRelationName(rel))));
5157}
5158
5159/*
5160 * ATWrongRelkindError
5161 *
5162 * Throw an error when a relation has been determined to be of the wrong
5163 * type.
5164 */
5165static void
5166ATWrongRelkindError(Relation rel, int allowed_targets)
5167{
5168 char *msg;
5169
5170 switch (allowed_targets)
5171 {
5172 case ATT_TABLE:
5173 msg = _("\"%s\" is not a table");
5174 break;
5175 case ATT_TABLE | ATT_VIEW:
5176 msg = _("\"%s\" is not a table or view");
5177 break;
5178 case ATT_TABLE | ATT_VIEW | ATT_FOREIGN_TABLE:
5179 msg = _("\"%s\" is not a table, view, or foreign table");
5180 break;
5181 case ATT_TABLE | ATT_VIEW | ATT_MATVIEW | ATT_INDEX:
5182 msg = _("\"%s\" is not a table, view, materialized view, or index");
5183 break;
5184 case ATT_TABLE | ATT_MATVIEW:
5185 msg = _("\"%s\" is not a table or materialized view");
5186 break;
5187 case ATT_TABLE | ATT_MATVIEW | ATT_INDEX:
5188 msg = _("\"%s\" is not a table, materialized view, or index");
5189 break;
5190 case ATT_TABLE | ATT_MATVIEW | ATT_FOREIGN_TABLE:
5191 msg = _("\"%s\" is not a table, materialized view, or foreign table");
5192 break;
5193 case ATT_TABLE | ATT_FOREIGN_TABLE:
5194 msg = _("\"%s\" is not a table or foreign table");
5195 break;
5196 case ATT_TABLE | ATT_COMPOSITE_TYPE | ATT_FOREIGN_TABLE:
5197 msg = _("\"%s\" is not a table, composite type, or foreign table");
5198 break;
5199 case ATT_TABLE | ATT_MATVIEW | ATT_INDEX | ATT_FOREIGN_TABLE:
5200 msg = _("\"%s\" is not a table, materialized view, index, or foreign table");
5201 break;
5202 case ATT_VIEW:
5203 msg = _("\"%s\" is not a view");
5204 break;
5205 case ATT_FOREIGN_TABLE:
5206 msg = _("\"%s\" is not a foreign table");
5207 break;
5208 default:
5209 /* shouldn't get here, add all necessary cases above */
5210 msg = _("\"%s\" is of the wrong type");
5211 break;
5212 }
5213
5214 ereport(ERROR,
5215 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
5216 errmsg(msg, RelationGetRelationName(rel))));
5217}
5218
5219/*
5220 * ATSimpleRecursion
5221 *
5222 * Simple table recursion sufficient for most ALTER TABLE operations.
5223 * All direct and indirect children are processed in an unspecified order.
5224 * Note that if a child inherits from the original table via multiple
5225 * inheritance paths, it will be visited just once.
5226 */
5227static void
5228ATSimpleRecursion(List **wqueue, Relation rel,
5229 AlterTableCmd *cmd, bool recurse, LOCKMODE lockmode)
5230{
5231 /*
5232 * Propagate to children if desired. Only plain tables, foreign tables
5233 * and partitioned tables have children, so no need to search for other
5234 * relkinds.
5235 */
5236 if (recurse &&
5237 (rel->rd_rel->relkind == RELKIND_RELATION ||
5238 rel->rd_rel->relkind == RELKIND_FOREIGN_TABLE ||
5239 rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE))
5240 {
5241 Oid relid = RelationGetRelid(rel);
5242 ListCell *child;
5243 List *children;
5244
5245 children = find_all_inheritors(relid, lockmode, NULL);
5246
5247 /*
5248 * find_all_inheritors does the recursive search of the inheritance
5249 * hierarchy, so all we have to do is process all of the relids in the
5250 * list that it returns.
5251 */
5252 foreach(child, children)
5253 {
5254 Oid childrelid = lfirst_oid(child);
5255 Relation childrel;
5256
5257 if (childrelid == relid)
5258 continue;
5259 /* find_all_inheritors already got lock */
5260 childrel = relation_open(childrelid, NoLock);
5261 CheckTableNotInUse(childrel, "ALTER TABLE");
5262 ATPrepCmd(wqueue, childrel, cmd, false, true, lockmode);
5263 relation_close(childrel, NoLock);
5264 }
5265 }
5266}
5267
5268/*
5269 * Obtain list of partitions of the given table, locking them all at the given
5270 * lockmode and ensuring that they all pass CheckTableNotInUse.
5271 *
5272 * This function is a no-op if the given relation is not a partitioned table;
5273 * in particular, nothing is done if it's a legacy inheritance parent.
5274 */
5275static void
5276ATCheckPartitionsNotInUse(Relation rel, LOCKMODE lockmode)
5277{
5278 if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
5279 {
5280 List *inh;
5281 ListCell *cell;
5282
5283 inh = find_all_inheritors(RelationGetRelid(rel), lockmode, NULL);
5284 /* first element is the parent rel; must ignore it */
5285 for_each_cell(cell, lnext(list_head(inh)))
5286 {
5287 Relation childrel;
5288
5289 /* find_all_inheritors already got lock */
5290 childrel = table_open(lfirst_oid(cell), NoLock);
5291 CheckTableNotInUse(childrel, "ALTER TABLE");
5292 table_close(childrel, NoLock);
5293 }
5294 list_free(inh);
5295 }
5296}
5297
5298/*
5299 * ATTypedTableRecursion
5300 *
5301 * Propagate ALTER TYPE operations to the typed tables of that type.
5302 * Also check the RESTRICT/CASCADE behavior. Given CASCADE, also permit
5303 * recursion to inheritance children of the typed tables.
5304 */
5305static void
5306ATTypedTableRecursion(List **wqueue, Relation rel, AlterTableCmd *cmd,
5307 LOCKMODE lockmode)
5308{
5309 ListCell *child;
5310 List *children;
5311
5312 Assert(rel->rd_rel->relkind == RELKIND_COMPOSITE_TYPE);
5313
5314 children = find_typed_table_dependencies(rel->rd_rel->reltype,
5315 RelationGetRelationName(rel),
5316 cmd->behavior);
5317
5318 foreach(child, children)
5319 {
5320 Oid childrelid = lfirst_oid(child);
5321 Relation childrel;
5322
5323 childrel = relation_open(childrelid, lockmode);
5324 CheckTableNotInUse(childrel, "ALTER TABLE");
5325 ATPrepCmd(wqueue, childrel, cmd, true, true, lockmode);
5326 relation_close(childrel, NoLock);
5327 }
5328}
5329
5330
5331/*
5332 * find_composite_type_dependencies
5333 *
5334 * Check to see if the type "typeOid" is being used as a column in some table
5335 * (possibly nested several levels deep in composite types, arrays, etc!).
5336 * Eventually, we'd like to propagate the check or rewrite operation
5337 * into such tables, but for now, just error out if we find any.
5338 *
5339 * Caller should provide either the associated relation of a rowtype,
5340 * or a type name (not both) for use in the error message, if any.
5341 *
5342 * Note that "typeOid" is not necessarily a composite type; it could also be
5343 * another container type such as an array or range, or a domain over one of
5344 * these things. The name of this function is therefore somewhat historical,
5345 * but it's not worth changing.
5346 *
5347 * We assume that functions and views depending on the type are not reasons
5348 * to reject the ALTER. (How safe is this really?)
5349 */
5350void
5351find_composite_type_dependencies(Oid typeOid, Relation origRelation,
5352 const char *origTypeName)
5353{
5354 Relation depRel;
5355 ScanKeyData key[2];
5356 SysScanDesc depScan;
5357 HeapTuple depTup;
5358
5359 /* since this function recurses, it could be driven to stack overflow */
5360 check_stack_depth();
5361
5362 /*
5363 * We scan pg_depend to find those things that depend on the given type.
5364 * (We assume we can ignore refobjsubid for a type.)
5365 */
5366 depRel = table_open(DependRelationId, AccessShareLock);
5367
5368 ScanKeyInit(&key[0],
5369 Anum_pg_depend_refclassid,
5370 BTEqualStrategyNumber, F_OIDEQ,
5371 ObjectIdGetDatum(TypeRelationId));
5372 ScanKeyInit(&key[1],
5373 Anum_pg_depend_refobjid,
5374 BTEqualStrategyNumber, F_OIDEQ,
5375 ObjectIdGetDatum(typeOid));
5376
5377 depScan = systable_beginscan(depRel, DependReferenceIndexId, true,
5378 NULL, 2, key);
5379
5380 while (HeapTupleIsValid(depTup = systable_getnext(depScan)))
5381 {
5382 Form_pg_depend pg_depend = (Form_pg_depend) GETSTRUCT(depTup);
5383 Relation rel;
5384 Form_pg_attribute att;
5385
5386 /* Check for directly dependent types */
5387 if (pg_depend->classid == TypeRelationId)
5388 {
5389 /*
5390 * This must be an array, domain, or range containing the given
5391 * type, so recursively check for uses of this type. Note that
5392 * any error message will mention the original type not the
5393 * container; this is intentional.
5394 */
5395 find_composite_type_dependencies(pg_depend->objid,
5396 origRelation, origTypeName);
5397 continue;
5398 }
5399
5400 /* Else, ignore dependees that aren't user columns of relations */
5401 /* (we assume system columns are never of interesting types) */
5402 if (pg_depend->classid != RelationRelationId ||
5403 pg_depend->objsubid <= 0)
5404 continue;
5405
5406 rel = relation_open(pg_depend->objid, AccessShareLock);
5407 att = TupleDescAttr(rel->rd_att, pg_depend->objsubid - 1);
5408
5409 if (rel->rd_rel->relkind == RELKIND_RELATION ||
5410 rel->rd_rel->relkind == RELKIND_MATVIEW ||
5411 rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
5412 {
5413 if (origTypeName)
5414 ereport(ERROR,
5415 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
5416 errmsg("cannot alter type \"%s\" because column \"%s.%s\" uses it",
5417 origTypeName,
5418 RelationGetRelationName(rel),
5419 NameStr(att->attname))));
5420 else if (origRelation->rd_rel->relkind == RELKIND_COMPOSITE_TYPE)
5421 ereport(ERROR,
5422 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
5423 errmsg("cannot alter type \"%s\" because column \"%s.%s\" uses it",
5424 RelationGetRelationName(origRelation),
5425 RelationGetRelationName(rel),
5426 NameStr(att->attname))));
5427 else if (origRelation->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
5428 ereport(ERROR,
5429 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
5430 errmsg("cannot alter foreign table \"%s\" because column \"%s.%s\" uses its row type",
5431 RelationGetRelationName(origRelation),
5432 RelationGetRelationName(rel),
5433 NameStr(att->attname))));
5434 else
5435 ereport(ERROR,
5436 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
5437 errmsg("cannot alter table \"%s\" because column \"%s.%s\" uses its row type",
5438 RelationGetRelationName(origRelation),
5439 RelationGetRelationName(rel),
5440 NameStr(att->attname))));
5441 }
5442 else if (OidIsValid(rel->rd_rel->reltype))
5443 {
5444 /*
5445 * A view or composite type itself isn't a problem, but we must
5446 * recursively check for indirect dependencies via its rowtype.
5447 */
5448 find_composite_type_dependencies(rel->rd_rel->reltype,
5449 origRelation, origTypeName);
5450 }
5451
5452 relation_close(rel, AccessShareLock);
5453 }
5454
5455 systable_endscan(depScan);
5456
5457 relation_close(depRel, AccessShareLock);
5458}
5459
5460
5461/*
5462 * find_typed_table_dependencies
5463 *
5464 * Check to see if a composite type is being used as the type of a
5465 * typed table. Abort if any are found and behavior is RESTRICT.
5466 * Else return the list of tables.
5467 */
5468static List *
5469find_typed_table_dependencies(Oid typeOid, const char *typeName, DropBehavior behavior)
5470{
5471 Relation classRel;
5472 ScanKeyData key[1];
5473 TableScanDesc scan;
5474 HeapTuple tuple;
5475 List *result = NIL;
5476
5477 classRel = table_open(RelationRelationId, AccessShareLock);
5478
5479 ScanKeyInit(&key[0],
5480 Anum_pg_class_reloftype,
5481 BTEqualStrategyNumber, F_OIDEQ,
5482 ObjectIdGetDatum(typeOid));
5483
5484 scan = table_beginscan_catalog(classRel, 1, key);
5485
5486 while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
5487 {
5488 Form_pg_class classform = (Form_pg_class) GETSTRUCT(tuple);
5489
5490 if (behavior == DROP_RESTRICT)
5491 ereport(ERROR,
5492 (errcode(ERRCODE_DEPENDENT_OBJECTS_STILL_EXIST),
5493 errmsg("cannot alter type \"%s\" because it is the type of a typed table",
5494 typeName),
5495 errhint("Use ALTER ... CASCADE to alter the typed tables too.")));
5496 else
5497 result = lappend_oid(result, classform->oid);
5498 }
5499
5500 table_endscan(scan);
5501 table_close(classRel, AccessShareLock);
5502
5503 return result;
5504}
5505
5506
5507/*
5508 * check_of_type
5509 *
5510 * Check whether a type is suitable for CREATE TABLE OF/ALTER TABLE OF. If it
5511 * isn't suitable, throw an error. Currently, we require that the type
5512 * originated with CREATE TYPE AS. We could support any row type, but doing so
5513 * would require handling a number of extra corner cases in the DDL commands.
5514 * (Also, allowing domain-over-composite would open up a can of worms about
5515 * whether and how the domain's constraints should apply to derived tables.)
5516 */
5517void
5518check_of_type(HeapTuple typetuple)
5519{
5520 Form_pg_type typ = (Form_pg_type) GETSTRUCT(typetuple);
5521 bool typeOk = false;
5522
5523 if (typ->typtype == TYPTYPE_COMPOSITE)
5524 {
5525 Relation typeRelation;
5526
5527 Assert(OidIsValid(typ->typrelid));
5528 typeRelation = relation_open(typ->typrelid, AccessShareLock);
5529 typeOk = (typeRelation->rd_rel->relkind == RELKIND_COMPOSITE_TYPE);
5530
5531 /*
5532 * Close the parent rel, but keep our AccessShareLock on it until xact
5533 * commit. That will prevent someone else from deleting or ALTERing
5534 * the type before the typed table creation/conversion commits.
5535 */
5536 relation_close(typeRelation, NoLock);
5537 }
5538 if (!typeOk)
5539 ereport(ERROR,
5540 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
5541 errmsg("type %s is not a composite type",
5542 format_type_be(typ->oid))));
5543}
5544
5545
5546/*
5547 * ALTER TABLE ADD COLUMN
5548 *
5549 * Adds an additional attribute to a relation making the assumption that
5550 * CHECK, NOT NULL, and FOREIGN KEY constraints will be removed from the
5551 * AT_AddColumn AlterTableCmd by parse_utilcmd.c and added as independent
5552 * AlterTableCmd's.
5553 *
5554 * ADD COLUMN cannot use the normal ALTER TABLE recursion mechanism, because we
5555 * have to decide at runtime whether to recurse or not depending on whether we
5556 * actually add a column or merely merge with an existing column. (We can't
5557 * check this in a static pre-pass because it won't handle multiple inheritance
5558 * situations correctly.)
5559 */
5560static void
5561ATPrepAddColumn(List **wqueue, Relation rel, bool recurse, bool recursing,
5562 bool is_view, AlterTableCmd *cmd, LOCKMODE lockmode)
5563{
5564 if (rel->rd_rel->reloftype && !recursing)
5565 ereport(ERROR,
5566 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
5567 errmsg("cannot add column to typed table")));
5568
5569 if (rel->rd_rel->relkind == RELKIND_COMPOSITE_TYPE)
5570 ATTypedTableRecursion(wqueue, rel, cmd, lockmode);
5571
5572 if (recurse && !is_view)
5573 cmd->subtype = AT_AddColumnRecurse;
5574}
5575
5576/*
5577 * Add a column to a table. The return value is the address of the
5578 * new column in the parent relation.
5579 */
5580static ObjectAddress
5581ATExecAddColumn(List **wqueue, AlteredTableInfo *tab, Relation rel,
5582 ColumnDef *colDef,
5583 bool recurse, bool recursing,
5584 bool if_not_exists, LOCKMODE lockmode)
5585{
5586 Oid myrelid = RelationGetRelid(rel);
5587 Relation pgclass,
5588 attrdesc;
5589 HeapTuple reltup;
5590 FormData_pg_attribute attribute;
5591 int newattnum;
5592 char relkind;
5593 HeapTuple typeTuple;
5594 Oid typeOid;
5595 int32 typmod;
5596 Oid collOid;
5597 Form_pg_type tform;
5598 Expr *defval;
5599 List *children;
5600 ListCell *child;
5601 AclResult aclresult;
5602 ObjectAddress address;
5603
5604 /* At top level, permission check was done in ATPrepCmd, else do it */
5605 if (recursing)
5606 ATSimplePermissions(rel, ATT_TABLE | ATT_FOREIGN_TABLE);
5607
5608 if (rel->rd_rel->relispartition && !recursing)
5609 ereport(ERROR,
5610 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
5611 errmsg("cannot add column to a partition")));
5612
5613 attrdesc = table_open(AttributeRelationId, RowExclusiveLock);
5614
5615 /*
5616 * Are we adding the column to a recursion child? If so, check whether to
5617 * merge with an existing definition for the column. If we do merge, we
5618 * must not recurse. Children will already have the column, and recursing
5619 * into them would mess up attinhcount.
5620 */
5621 if (colDef->inhcount > 0)
5622 {
5623 HeapTuple tuple;
5624
5625 /* Does child already have a column by this name? */
5626 tuple = SearchSysCacheCopyAttName(myrelid, colDef->colname);
5627 if (HeapTupleIsValid(tuple))
5628 {
5629 Form_pg_attribute childatt = (Form_pg_attribute) GETSTRUCT(tuple);
5630 Oid ctypeId;
5631 int32 ctypmod;
5632 Oid ccollid;
5633
5634 /* Child column must match on type, typmod, and collation */
5635 typenameTypeIdAndMod(NULL, colDef->typeName, &ctypeId, &ctypmod);
5636 if (ctypeId != childatt->atttypid ||
5637 ctypmod != childatt->atttypmod)
5638 ereport(ERROR,
5639 (errcode(ERRCODE_DATATYPE_MISMATCH),
5640 errmsg("child table \"%s\" has different type for column \"%s\"",
5641 RelationGetRelationName(rel), colDef->colname)));
5642 ccollid = GetColumnDefCollation(NULL, colDef, ctypeId);
5643 if (ccollid != childatt->attcollation)
5644 ereport(ERROR,
5645 (errcode(ERRCODE_COLLATION_MISMATCH),
5646 errmsg("child table \"%s\" has different collation for column \"%s\"",
5647 RelationGetRelationName(rel), colDef->colname),
5648 errdetail("\"%s\" versus \"%s\"",
5649 get_collation_name(ccollid),
5650 get_collation_name(childatt->attcollation))));
5651
5652 /* Bump the existing child att's inhcount */
5653 childatt->attinhcount++;
5654 CatalogTupleUpdate(attrdesc, &tuple->t_self, tuple);
5655
5656 heap_freetuple(tuple);
5657
5658 /* Inform the user about the merge */
5659 ereport(NOTICE,
5660 (errmsg("merging definition of column \"%s\" for child \"%s\"",
5661 colDef->colname, RelationGetRelationName(rel))));
5662
5663 table_close(attrdesc, RowExclusiveLock);
5664 return InvalidObjectAddress;
5665 }
5666 }
5667
5668 pgclass = table_open(RelationRelationId, RowExclusiveLock);
5669
5670 reltup = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(myrelid));
5671 if (!HeapTupleIsValid(reltup))
5672 elog(ERROR, "cache lookup failed for relation %u", myrelid);
5673 relkind = ((Form_pg_class) GETSTRUCT(reltup))->relkind;
5674
5675 /*
5676 * Cannot add identity column if table has children, because identity does
5677 * not inherit. (Adding column and identity separately will work.)
5678 */
5679 if (colDef->identity &&
5680 recurse &&
5681 find_inheritance_children(myrelid, NoLock) != NIL)
5682 ereport(ERROR,
5683 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
5684 errmsg("cannot recursively add identity column to table that has child tables")));
5685
5686 /* skip if the name already exists and if_not_exists is true */
5687 if (!check_for_column_name_collision(rel, colDef->colname, if_not_exists))
5688 {
5689 table_close(attrdesc, RowExclusiveLock);
5690 heap_freetuple(reltup);
5691 table_close(pgclass, RowExclusiveLock);
5692 return InvalidObjectAddress;
5693 }
5694
5695 /* Determine the new attribute's number */
5696 newattnum = ((Form_pg_class) GETSTRUCT(reltup))->relnatts + 1;
5697 if (newattnum > MaxHeapAttributeNumber)
5698 ereport(ERROR,
5699 (errcode(ERRCODE_TOO_MANY_COLUMNS),
5700 errmsg("tables can have at most %d columns",
5701 MaxHeapAttributeNumber)));
5702
5703 typeTuple = typenameType(NULL, colDef->typeName, &typmod);
5704 tform = (Form_pg_type) GETSTRUCT(typeTuple);
5705 typeOid = tform->oid;
5706
5707 aclresult = pg_type_aclcheck(typeOid, GetUserId(), ACL_USAGE);
5708 if (aclresult != ACLCHECK_OK)
5709 aclcheck_error_type(aclresult, typeOid);
5710
5711 collOid = GetColumnDefCollation(NULL, colDef, typeOid);
5712
5713 /* make sure datatype is legal for a column */
5714 CheckAttributeType(colDef->colname, typeOid, collOid,
5715 list_make1_oid(rel->rd_rel->reltype),
5716 0);
5717
5718 /* construct new attribute's pg_attribute entry */
5719 attribute.attrelid = myrelid;
5720 namestrcpy(&(attribute.attname), colDef->colname);
5721 attribute.atttypid = typeOid;
5722 attribute.attstattarget = (newattnum > 0) ? -1 : 0;
5723 attribute.attlen = tform->typlen;
5724 attribute.atttypmod = typmod;
5725 attribute.attnum = newattnum;
5726 attribute.attbyval = tform->typbyval;
5727 attribute.attndims = list_length(colDef->typeName->arrayBounds);
5728 attribute.attstorage = tform->typstorage;
5729 attribute.attalign = tform->typalign;
5730 attribute.attnotnull = colDef->is_not_null;
5731 attribute.atthasdef = false;
5732 attribute.atthasmissing = false;
5733 attribute.attidentity = colDef->identity;
5734 attribute.attgenerated = colDef->generated;
5735 attribute.attisdropped = false;
5736 attribute.attislocal = colDef->is_local;
5737 attribute.attinhcount = colDef->inhcount;
5738 attribute.attcollation = collOid;
5739 /* attribute.attacl is handled by InsertPgAttributeTuple */
5740
5741 ReleaseSysCache(typeTuple);
5742
5743 InsertPgAttributeTuple(attrdesc, &attribute, NULL);
5744
5745 table_close(attrdesc, RowExclusiveLock);
5746
5747 /*
5748 * Update pg_class tuple as appropriate
5749 */
5750 ((Form_pg_class) GETSTRUCT(reltup))->relnatts = newattnum;
5751
5752 CatalogTupleUpdate(pgclass, &reltup->t_self, reltup);
5753
5754 heap_freetuple(reltup);
5755
5756 /* Post creation hook for new attribute */
5757 InvokeObjectPostCreateHook(RelationRelationId, myrelid, newattnum);
5758
5759 table_close(pgclass, RowExclusiveLock);
5760
5761 /* Make the attribute's catalog entry visible */
5762 CommandCounterIncrement();
5763
5764 /*
5765 * Store the DEFAULT, if any, in the catalogs
5766 */
5767 if (colDef->raw_default)
5768 {
5769 RawColumnDefault *rawEnt;
5770
5771 rawEnt = (RawColumnDefault *) palloc(sizeof(RawColumnDefault));
5772 rawEnt->attnum = attribute.attnum;
5773 rawEnt->raw_default = copyObject(colDef->raw_default);
5774
5775 /*
5776 * Attempt to skip a complete table rewrite by storing the specified
5777 * DEFAULT value outside of the heap. This may be disabled inside
5778 * AddRelationNewConstraints if the optimization cannot be applied.
5779 */
5780 rawEnt->missingMode = (!colDef->generated);
5781
5782 rawEnt->generated = colDef->generated;
5783
5784 /*
5785 * This function is intended for CREATE TABLE, so it processes a
5786 * _list_ of defaults, but we just do one.
5787 */
5788 AddRelationNewConstraints(rel, list_make1(rawEnt), NIL,
5789 false, true, false, NULL);
5790
5791 /* Make the additional catalog changes visible */
5792 CommandCounterIncrement();
5793
5794 /*
5795 * Did the request for a missing value work? If not we'll have to do a
5796 * rewrite
5797 */
5798 if (!rawEnt->missingMode)
5799 tab->rewrite |= AT_REWRITE_DEFAULT_VAL;
5800 }
5801
5802 /*
5803 * Tell Phase 3 to fill in the default expression, if there is one.
5804 *
5805 * If there is no default, Phase 3 doesn't have to do anything, because
5806 * that effectively means that the default is NULL. The heap tuple access
5807 * routines always check for attnum > # of attributes in tuple, and return
5808 * NULL if so, so without any modification of the tuple data we will get
5809 * the effect of NULL values in the new column.
5810 *
5811 * An exception occurs when the new column is of a domain type: the domain
5812 * might have a NOT NULL constraint, or a check constraint that indirectly
5813 * rejects nulls. If there are any domain constraints then we construct
5814 * an explicit NULL default value that will be passed through
5815 * CoerceToDomain processing. (This is a tad inefficient, since it causes
5816 * rewriting the table which we really don't have to do, but the present
5817 * design of domain processing doesn't offer any simple way of checking
5818 * the constraints more directly.)
5819 *
5820 * Note: we use build_column_default, and not just the cooked default
5821 * returned by AddRelationNewConstraints, so that the right thing happens
5822 * when a datatype's default applies.
5823 *
5824 * We skip this step completely for views and foreign tables. For a view,
5825 * we can only get here from CREATE OR REPLACE VIEW, which historically
5826 * doesn't set up defaults, not even for domain-typed columns. And in any
5827 * case we mustn't invoke Phase 3 on a view or foreign table, since they
5828 * have no storage.
5829 */
5830 if (relkind != RELKIND_VIEW && relkind != RELKIND_COMPOSITE_TYPE
5831 && relkind != RELKIND_FOREIGN_TABLE && attribute.attnum > 0)
5832 {
5833 /*
5834 * For an identity column, we can't use build_column_default(),
5835 * because the sequence ownership isn't set yet. So do it manually.
5836 */
5837 if (colDef->identity)
5838 {
5839 NextValueExpr *nve = makeNode(NextValueExpr);
5840
5841 nve->seqid = RangeVarGetRelid(colDef->identitySequence, NoLock, false);
5842 nve->typeId = typeOid;
5843
5844 defval = (Expr *) nve;
5845
5846 /* must do a rewrite for identity columns */
5847 tab->rewrite |= AT_REWRITE_DEFAULT_VAL;
5848 }
5849 else
5850 defval = (Expr *) build_column_default(rel, attribute.attnum);
5851
5852 if (!defval && DomainHasConstraints(typeOid))
5853 {
5854 Oid baseTypeId;
5855 int32 baseTypeMod;
5856 Oid baseTypeColl;
5857
5858 baseTypeMod = typmod;
5859 baseTypeId = getBaseTypeAndTypmod(typeOid, &baseTypeMod);
5860 baseTypeColl = get_typcollation(baseTypeId);
5861 defval = (Expr *) makeNullConst(baseTypeId, baseTypeMod, baseTypeColl);
5862 defval = (Expr *) coerce_to_target_type(NULL,
5863 (Node *) defval,
5864 baseTypeId,
5865 typeOid,
5866 typmod,
5867 COERCION_ASSIGNMENT,
5868 COERCE_IMPLICIT_CAST,
5869 -1);
5870 if (defval == NULL) /* should not happen */
5871 elog(ERROR, "failed to coerce base type to domain");
5872 }
5873
5874 if (defval)
5875 {
5876 NewColumnValue *newval;
5877
5878 newval = (NewColumnValue *) palloc0(sizeof(NewColumnValue));
5879 newval->attnum = attribute.attnum;
5880 newval->expr = expression_planner(defval);
5881
5882 tab->newvals = lappend(tab->newvals, newval);
5883 }
5884
5885 if (DomainHasConstraints(typeOid))
5886 tab->rewrite |= AT_REWRITE_DEFAULT_VAL;
5887
5888 if (!TupleDescAttr(rel->rd_att, attribute.attnum - 1)->atthasmissing)
5889 {
5890 /*
5891 * If the new column is NOT NULL, and there is no missing value,
5892 * tell Phase 3 it needs to check for NULLs.
5893 */
5894 tab->verify_new_notnull |= colDef->is_not_null;
5895 }
5896 }
5897
5898 /*
5899 * Add needed dependency entries for the new column.
5900 */
5901 add_column_datatype_dependency(myrelid, newattnum, attribute.atttypid);
5902 add_column_collation_dependency(myrelid, newattnum, attribute.attcollation);
5903
5904 /*
5905 * Propagate to children as appropriate. Unlike most other ALTER
5906 * routines, we have to do this one level of recursion at a time; we can't
5907 * use find_all_inheritors to do it in one pass.
5908 */
5909 children = find_inheritance_children(RelationGetRelid(rel), lockmode);
5910
5911 /*
5912 * If we are told not to recurse, there had better not be any child
5913 * tables; else the addition would put them out of step.
5914 */
5915 if (children && !recurse)
5916 ereport(ERROR,
5917 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
5918 errmsg("column must be added to child tables too")));
5919
5920 /* Children should see column as singly inherited */
5921 if (!recursing)
5922 {
5923 colDef = copyObject(colDef);
5924 colDef->inhcount = 1;
5925 colDef->is_local = false;
5926 }
5927
5928 foreach(child, children)
5929 {
5930 Oid childrelid = lfirst_oid(child);
5931 Relation childrel;
5932 AlteredTableInfo *childtab;
5933
5934 /* find_inheritance_children already got lock */
5935 childrel = table_open(childrelid, NoLock);
5936 CheckTableNotInUse(childrel, "ALTER TABLE");
5937
5938 /* Find or create work queue entry for this table */
5939 childtab = ATGetQueueEntry(wqueue, childrel);
5940
5941 /* Recurse to child; return value is ignored */
5942 ATExecAddColumn(wqueue, childtab, childrel,
5943 colDef, recurse, true,
5944 if_not_exists, lockmode);
5945
5946 table_close(childrel, NoLock);
5947 }
5948
5949 ObjectAddressSubSet(address, RelationRelationId, myrelid, newattnum);
5950 return address;
5951}
5952
5953/*
5954 * If a new or renamed column will collide with the name of an existing
5955 * column and if_not_exists is false then error out, else do nothing.
5956 */
5957static bool
5958check_for_column_name_collision(Relation rel, const char *colname,
5959 bool if_not_exists)
5960{
5961 HeapTuple attTuple;
5962 int attnum;
5963
5964 /*
5965 * this test is deliberately not attisdropped-aware, since if one tries to
5966 * add a column matching a dropped column name, it's gonna fail anyway.
5967 */
5968 attTuple = SearchSysCache2(ATTNAME,
5969 ObjectIdGetDatum(RelationGetRelid(rel)),
5970 PointerGetDatum(colname));
5971 if (!HeapTupleIsValid(attTuple))
5972 return true;
5973
5974 attnum = ((Form_pg_attribute) GETSTRUCT(attTuple))->attnum;
5975 ReleaseSysCache(attTuple);
5976
5977 /*
5978 * We throw a different error message for conflicts with system column
5979 * names, since they are normally not shown and the user might otherwise
5980 * be confused about the reason for the conflict.
5981 */
5982 if (attnum <= 0)
5983 ereport(ERROR,
5984 (errcode(ERRCODE_DUPLICATE_COLUMN),
5985 errmsg("column name \"%s\" conflicts with a system column name",
5986 colname)));
5987 else
5988 {
5989 if (if_not_exists)
5990 {
5991 ereport(NOTICE,
5992 (errcode(ERRCODE_DUPLICATE_COLUMN),
5993 errmsg("column \"%s\" of relation \"%s\" already exists, skipping",
5994 colname, RelationGetRelationName(rel))));
5995 return false;
5996 }
5997
5998 ereport(ERROR,
5999 (errcode(ERRCODE_DUPLICATE_COLUMN),
6000 errmsg("column \"%s\" of relation \"%s\" already exists",
6001 colname, RelationGetRelationName(rel))));
6002 }
6003
6004 return true;
6005}
6006
6007/*
6008 * Install a column's dependency on its datatype.
6009 */
6010static void
6011add_column_datatype_dependency(Oid relid, int32 attnum, Oid typid)
6012{
6013 ObjectAddress myself,
6014 referenced;
6015
6016 myself.classId = RelationRelationId;
6017 myself.objectId = relid;
6018 myself.objectSubId = attnum;
6019 referenced.classId = TypeRelationId;
6020 referenced.objectId = typid;
6021 referenced.objectSubId = 0;
6022 recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
6023}
6024
6025/*
6026 * Install a column's dependency on its collation.
6027 */
6028static void
6029add_column_collation_dependency(Oid relid, int32 attnum, Oid collid)
6030{
6031 ObjectAddress myself,
6032 referenced;
6033
6034 /* We know the default collation is pinned, so don't bother recording it */
6035 if (OidIsValid(collid) && collid != DEFAULT_COLLATION_OID)
6036 {
6037 myself.classId = RelationRelationId;
6038 myself.objectId = relid;
6039 myself.objectSubId = attnum;
6040 referenced.classId = CollationRelationId;
6041 referenced.objectId = collid;
6042 referenced.objectSubId = 0;
6043 recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
6044 }
6045}
6046
6047/*
6048 * ALTER TABLE ALTER COLUMN DROP NOT NULL
6049 */
6050
6051static void
6052ATPrepDropNotNull(Relation rel, bool recurse, bool recursing)
6053{
6054 /*
6055 * If the parent is a partitioned table, like check constraints, we do not
6056 * support removing the NOT NULL while partitions exist.
6057 */
6058 if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
6059 {
6060 PartitionDesc partdesc = RelationGetPartitionDesc(rel);
6061
6062 Assert(partdesc != NULL);
6063 if (partdesc->nparts > 0 && !recurse && !recursing)
6064 ereport(ERROR,
6065 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
6066 errmsg("cannot remove constraint from only the partitioned table when partitions exist"),
6067 errhint("Do not specify the ONLY keyword.")));
6068 }
6069}
6070
6071/*
6072 * Return the address of the modified column. If the column was already
6073 * nullable, InvalidObjectAddress is returned.
6074 */
6075static ObjectAddress
6076ATExecDropNotNull(Relation rel, const char *colName, LOCKMODE lockmode)
6077{
6078 HeapTuple tuple;
6079 Form_pg_attribute attTup;
6080 AttrNumber attnum;
6081 Relation attr_rel;
6082 List *indexoidlist;
6083 ListCell *indexoidscan;
6084 ObjectAddress address;
6085
6086 /*
6087 * lookup the attribute
6088 */
6089 attr_rel = table_open(AttributeRelationId, RowExclusiveLock);
6090
6091 tuple = SearchSysCacheCopyAttName(RelationGetRelid(rel), colName);
6092 if (!HeapTupleIsValid(tuple))
6093 ereport(ERROR,
6094 (errcode(ERRCODE_UNDEFINED_COLUMN),
6095 errmsg("column \"%s\" of relation \"%s\" does not exist",
6096 colName, RelationGetRelationName(rel))));
6097 attTup = (Form_pg_attribute) GETSTRUCT(tuple);
6098 attnum = attTup->attnum;
6099
6100 /* Prevent them from altering a system attribute */
6101 if (attnum <= 0)
6102 ereport(ERROR,
6103 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6104 errmsg("cannot alter system column \"%s\"",
6105 colName)));
6106
6107 if (attTup->attidentity)
6108 ereport(ERROR,
6109 (errcode(ERRCODE_SYNTAX_ERROR),
6110 errmsg("column \"%s\" of relation \"%s\" is an identity column",
6111 colName, RelationGetRelationName(rel))));
6112
6113 /*
6114 * Check that the attribute is not in a primary key
6115 *
6116 * Note: we'll throw error even if the pkey index is not valid.
6117 */
6118
6119 /* Loop over all indexes on the relation */
6120 indexoidlist = RelationGetIndexList(rel);
6121
6122 foreach(indexoidscan, indexoidlist)
6123 {
6124 Oid indexoid = lfirst_oid(indexoidscan);
6125 HeapTuple indexTuple;
6126 Form_pg_index indexStruct;
6127 int i;
6128
6129 indexTuple = SearchSysCache1(INDEXRELID, ObjectIdGetDatum(indexoid));
6130 if (!HeapTupleIsValid(indexTuple))
6131 elog(ERROR, "cache lookup failed for index %u", indexoid);
6132 indexStruct = (Form_pg_index) GETSTRUCT(indexTuple);
6133
6134 /* If the index is not a primary key, skip the check */
6135 if (indexStruct->indisprimary)
6136 {
6137 /*
6138 * Loop over each attribute in the primary key and see if it
6139 * matches the to-be-altered attribute
6140 */
6141 for (i = 0; i < indexStruct->indnkeyatts; i++)
6142 {
6143 if (indexStruct->indkey.values[i] == attnum)
6144 ereport(ERROR,
6145 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
6146 errmsg("column \"%s\" is in a primary key",
6147 colName)));
6148 }
6149 }
6150
6151 ReleaseSysCache(indexTuple);
6152 }
6153
6154 list_free(indexoidlist);
6155
6156 /* If rel is partition, shouldn't drop NOT NULL if parent has the same */
6157 if (rel->rd_rel->relispartition)
6158 {
6159 Oid parentId = get_partition_parent(RelationGetRelid(rel));
6160 Relation parent = table_open(parentId, AccessShareLock);
6161 TupleDesc tupDesc = RelationGetDescr(parent);
6162 AttrNumber parent_attnum;
6163
6164 parent_attnum = get_attnum(parentId, colName);
6165 if (TupleDescAttr(tupDesc, parent_attnum - 1)->attnotnull)
6166 ereport(ERROR,
6167 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
6168 errmsg("column \"%s\" is marked NOT NULL in parent table",
6169 colName)));
6170 table_close(parent, AccessShareLock);
6171 }
6172
6173 /*
6174 * Okay, actually perform the catalog change ... if needed
6175 */
6176 if (attTup->attnotnull)
6177 {
6178 attTup->attnotnull = false;
6179
6180 CatalogTupleUpdate(attr_rel, &tuple->t_self, tuple);
6181
6182 ObjectAddressSubSet(address, RelationRelationId,
6183 RelationGetRelid(rel), attnum);
6184 }
6185 else
6186 address = InvalidObjectAddress;
6187
6188 InvokeObjectPostAlterHook(RelationRelationId,
6189 RelationGetRelid(rel), attnum);
6190
6191 table_close(attr_rel, RowExclusiveLock);
6192
6193 return address;
6194}
6195
6196/*
6197 * ALTER TABLE ALTER COLUMN SET NOT NULL
6198 */
6199
6200static void
6201ATPrepSetNotNull(List **wqueue, Relation rel,
6202 AlterTableCmd *cmd, bool recurse, bool recursing,
6203 LOCKMODE lockmode)
6204{
6205 /*
6206 * If we're already recursing, there's nothing to do; the topmost
6207 * invocation of ATSimpleRecursion already visited all children.
6208 */
6209 if (recursing)
6210 return;
6211
6212 /*
6213 * If we have ALTER TABLE ONLY ... SET NOT NULL on a partitioned table,
6214 * apply ALTER TABLE ... CHECK NOT NULL to every child. Otherwise, use
6215 * normal recursion logic.
6216 */
6217 if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE &&
6218 !recurse)
6219 {
6220 AlterTableCmd *newcmd = makeNode(AlterTableCmd);
6221
6222 newcmd->subtype = AT_CheckNotNull;
6223 newcmd->name = pstrdup(cmd->name);
6224 ATSimpleRecursion(wqueue, rel, newcmd, true, lockmode);
6225 }
6226 else
6227 ATSimpleRecursion(wqueue, rel, cmd, recurse, lockmode);
6228}
6229
6230/*
6231 * Return the address of the modified column. If the column was already NOT
6232 * NULL, InvalidObjectAddress is returned.
6233 */
6234static ObjectAddress
6235ATExecSetNotNull(AlteredTableInfo *tab, Relation rel,
6236 const char *colName, LOCKMODE lockmode)
6237{
6238 HeapTuple tuple;
6239 AttrNumber attnum;
6240 Relation attr_rel;
6241 ObjectAddress address;
6242
6243 /*
6244 * lookup the attribute
6245 */
6246 attr_rel = table_open(AttributeRelationId, RowExclusiveLock);
6247
6248 tuple = SearchSysCacheCopyAttName(RelationGetRelid(rel), colName);
6249
6250 if (!HeapTupleIsValid(tuple))
6251 ereport(ERROR,
6252 (errcode(ERRCODE_UNDEFINED_COLUMN),
6253 errmsg("column \"%s\" of relation \"%s\" does not exist",
6254 colName, RelationGetRelationName(rel))));
6255
6256 attnum = ((Form_pg_attribute) GETSTRUCT(tuple))->attnum;
6257
6258 /* Prevent them from altering a system attribute */
6259 if (attnum <= 0)
6260 ereport(ERROR,
6261 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6262 errmsg("cannot alter system column \"%s\"",
6263 colName)));
6264
6265 /*
6266 * Okay, actually perform the catalog change ... if needed
6267 */
6268 if (!((Form_pg_attribute) GETSTRUCT(tuple))->attnotnull)
6269 {
6270 ((Form_pg_attribute) GETSTRUCT(tuple))->attnotnull = true;
6271
6272 CatalogTupleUpdate(attr_rel, &tuple->t_self, tuple);
6273
6274 /*
6275 * Ordinarily phase 3 must ensure that no NULLs exist in columns that
6276 * are set NOT NULL; however, if we can find a constraint which proves
6277 * this then we can skip that. We needn't bother looking if we've
6278 * already found that we must verify some other NOT NULL constraint.
6279 */
6280 if (!tab->verify_new_notnull &&
6281 !NotNullImpliedByRelConstraints(rel, (Form_pg_attribute) GETSTRUCT(tuple)))
6282 {
6283 /* Tell Phase 3 it needs to test the constraint */
6284 tab->verify_new_notnull = true;
6285 }
6286
6287 ObjectAddressSubSet(address, RelationRelationId,
6288 RelationGetRelid(rel), attnum);
6289 }
6290 else
6291 address = InvalidObjectAddress;
6292
6293 InvokeObjectPostAlterHook(RelationRelationId,
6294 RelationGetRelid(rel), attnum);
6295
6296 table_close(attr_rel, RowExclusiveLock);
6297
6298 return address;
6299}
6300
6301/*
6302 * ALTER TABLE ALTER COLUMN CHECK NOT NULL
6303 *
6304 * This doesn't exist in the grammar, but we generate AT_CheckNotNull
6305 * commands against the partitions of a partitioned table if the user
6306 * writes ALTER TABLE ONLY ... SET NOT NULL on the partitioned table,
6307 * or tries to create a primary key on it (which internally creates
6308 * AT_SetNotNull on the partitioned table). Such a command doesn't
6309 * allow us to actually modify any partition, but we want to let it
6310 * go through if the partitions are already properly marked.
6311 *
6312 * In future, this might need to adjust the child table's state, likely
6313 * by incrementing an inheritance count for the attnotnull constraint.
6314 * For now we need only check for the presence of the flag.
6315 */
6316static void
6317ATExecCheckNotNull(AlteredTableInfo *tab, Relation rel,
6318 const char *colName, LOCKMODE lockmode)
6319{
6320 HeapTuple tuple;
6321
6322 tuple = SearchSysCacheAttName(RelationGetRelid(rel), colName);
6323
6324 if (!HeapTupleIsValid(tuple))
6325 ereport(ERROR,
6326 (errcode(ERRCODE_UNDEFINED_COLUMN),
6327 errmsg("column \"%s\" of relation \"%s\" does not exist",
6328 colName, RelationGetRelationName(rel))));
6329
6330 if (!((Form_pg_attribute) GETSTRUCT(tuple))->attnotnull)
6331 ereport(ERROR,
6332 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
6333 errmsg("constraint must be added to child tables too"),
6334 errdetail("Column \"%s\" of relation \"%s\" is not already NOT NULL.",
6335 colName, RelationGetRelationName(rel)),
6336 errhint("Do not specify the ONLY keyword.")));
6337
6338 ReleaseSysCache(tuple);
6339}
6340
6341/*
6342 * NotNullImpliedByRelConstraints
6343 * Does rel's existing constraints imply NOT NULL for the given attribute?
6344 */
6345static bool
6346NotNullImpliedByRelConstraints(Relation rel, Form_pg_attribute attr)
6347{
6348 NullTest *nnulltest = makeNode(NullTest);
6349
6350 nnulltest->arg = (Expr *) makeVar(1,
6351 attr->attnum,
6352 attr->atttypid,
6353 attr->atttypmod,
6354 attr->attcollation,
6355 0);
6356 nnulltest->nulltesttype = IS_NOT_NULL;
6357
6358 /*
6359 * argisrow = false is correct even for a composite column, because
6360 * attnotnull does not represent a SQL-spec IS NOT NULL test in such a
6361 * case, just IS DISTINCT FROM NULL.
6362 */
6363 nnulltest->argisrow = false;
6364 nnulltest->location = -1;
6365
6366 if (ConstraintImpliedByRelConstraint(rel, list_make1(nnulltest), NIL))
6367 {
6368 ereport(DEBUG1,
6369 (errmsg("existing constraints on column \"%s\".\"%s\" are sufficient to prove that it does not contain nulls",
6370 RelationGetRelationName(rel), NameStr(attr->attname))));
6371 return true;
6372 }
6373
6374 return false;
6375}
6376
6377/*
6378 * ALTER TABLE ALTER COLUMN SET/DROP DEFAULT
6379 *
6380 * Return the address of the affected column.
6381 */
6382static ObjectAddress
6383ATExecColumnDefault(Relation rel, const char *colName,
6384 Node *newDefault, LOCKMODE lockmode)
6385{
6386 TupleDesc tupdesc = RelationGetDescr(rel);
6387 AttrNumber attnum;
6388 ObjectAddress address;
6389
6390 /*
6391 * get the number of the attribute
6392 */
6393 attnum = get_attnum(RelationGetRelid(rel), colName);
6394 if (attnum == InvalidAttrNumber)
6395 ereport(ERROR,
6396 (errcode(ERRCODE_UNDEFINED_COLUMN),
6397 errmsg("column \"%s\" of relation \"%s\" does not exist",
6398 colName, RelationGetRelationName(rel))));
6399
6400 /* Prevent them from altering a system attribute */
6401 if (attnum <= 0)
6402 ereport(ERROR,
6403 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6404 errmsg("cannot alter system column \"%s\"",
6405 colName)));
6406
6407 if (TupleDescAttr(tupdesc, attnum - 1)->attidentity)
6408 ereport(ERROR,
6409 (errcode(ERRCODE_SYNTAX_ERROR),
6410 errmsg("column \"%s\" of relation \"%s\" is an identity column",
6411 colName, RelationGetRelationName(rel)),
6412 newDefault ? 0 : errhint("Use ALTER TABLE ... ALTER COLUMN ... DROP IDENTITY instead.")));
6413
6414 if (TupleDescAttr(tupdesc, attnum - 1)->attgenerated)
6415 ereport(ERROR,
6416 (errcode(ERRCODE_SYNTAX_ERROR),
6417 errmsg("column \"%s\" of relation \"%s\" is a generated column",
6418 colName, RelationGetRelationName(rel))));
6419
6420 /*
6421 * Remove any old default for the column. We use RESTRICT here for
6422 * safety, but at present we do not expect anything to depend on the
6423 * default.
6424 *
6425 * We treat removing the existing default as an internal operation when it
6426 * is preparatory to adding a new default, but as a user-initiated
6427 * operation when the user asked for a drop.
6428 */
6429 RemoveAttrDefault(RelationGetRelid(rel), attnum, DROP_RESTRICT, false,
6430 newDefault == NULL ? false : true);
6431
6432 if (newDefault)
6433 {
6434 /* SET DEFAULT */
6435 RawColumnDefault *rawEnt;
6436
6437 rawEnt = (RawColumnDefault *) palloc(sizeof(RawColumnDefault));
6438 rawEnt->attnum = attnum;
6439 rawEnt->raw_default = newDefault;
6440 rawEnt->missingMode = false;
6441 rawEnt->generated = '\0';
6442
6443 /*
6444 * This function is intended for CREATE TABLE, so it processes a
6445 * _list_ of defaults, but we just do one.
6446 */
6447 AddRelationNewConstraints(rel, list_make1(rawEnt), NIL,
6448 false, true, false, NULL);
6449 }
6450
6451 ObjectAddressSubSet(address, RelationRelationId,
6452 RelationGetRelid(rel), attnum);
6453 return address;
6454}
6455
6456/*
6457 * ALTER TABLE ALTER COLUMN ADD IDENTITY
6458 *
6459 * Return the address of the affected column.
6460 */
6461static ObjectAddress
6462ATExecAddIdentity(Relation rel, const char *colName,
6463 Node *def, LOCKMODE lockmode)
6464{
6465 Relation attrelation;
6466 HeapTuple tuple;
6467 Form_pg_attribute attTup;
6468 AttrNumber attnum;
6469 ObjectAddress address;
6470 ColumnDef *cdef = castNode(ColumnDef, def);
6471
6472 attrelation = table_open(AttributeRelationId, RowExclusiveLock);
6473
6474 tuple = SearchSysCacheCopyAttName(RelationGetRelid(rel), colName);
6475 if (!HeapTupleIsValid(tuple))
6476 ereport(ERROR,
6477 (errcode(ERRCODE_UNDEFINED_COLUMN),
6478 errmsg("column \"%s\" of relation \"%s\" does not exist",
6479 colName, RelationGetRelationName(rel))));
6480 attTup = (Form_pg_attribute) GETSTRUCT(tuple);
6481 attnum = attTup->attnum;
6482
6483 /* Can't alter a system attribute */
6484 if (attnum <= 0)
6485 ereport(ERROR,
6486 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6487 errmsg("cannot alter system column \"%s\"",
6488 colName)));
6489
6490 /*
6491 * Creating a column as identity implies NOT NULL, so adding the identity
6492 * to an existing column that is not NOT NULL would create a state that
6493 * cannot be reproduced without contortions.
6494 */
6495 if (!attTup->attnotnull)
6496 ereport(ERROR,
6497 (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
6498 errmsg("column \"%s\" of relation \"%s\" must be declared NOT NULL before identity can be added",
6499 colName, RelationGetRelationName(rel))));
6500
6501 if (attTup->attidentity)
6502 ereport(ERROR,
6503 (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
6504 errmsg("column \"%s\" of relation \"%s\" is already an identity column",
6505 colName, RelationGetRelationName(rel))));
6506
6507 if (attTup->atthasdef)
6508 ereport(ERROR,
6509 (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
6510 errmsg("column \"%s\" of relation \"%s\" already has a default value",
6511 colName, RelationGetRelationName(rel))));
6512
6513 attTup->attidentity = cdef->identity;
6514 CatalogTupleUpdate(attrelation, &tuple->t_self, tuple);
6515
6516 InvokeObjectPostAlterHook(RelationRelationId,
6517 RelationGetRelid(rel),
6518 attTup->attnum);
6519 ObjectAddressSubSet(address, RelationRelationId,
6520 RelationGetRelid(rel), attnum);
6521 heap_freetuple(tuple);
6522
6523 table_close(attrelation, RowExclusiveLock);
6524
6525 return address;
6526}
6527
6528/*
6529 * ALTER TABLE ALTER COLUMN SET { GENERATED or sequence options }
6530 *
6531 * Return the address of the affected column.
6532 */
6533static ObjectAddress
6534ATExecSetIdentity(Relation rel, const char *colName, Node *def, LOCKMODE lockmode)
6535{
6536 ListCell *option;
6537 DefElem *generatedEl = NULL;
6538 HeapTuple tuple;
6539 Form_pg_attribute attTup;
6540 AttrNumber attnum;
6541 Relation attrelation;
6542 ObjectAddress address;
6543
6544 foreach(option, castNode(List, def))
6545 {
6546 DefElem *defel = lfirst_node(DefElem, option);
6547
6548 if (strcmp(defel->defname, "generated") == 0)
6549 {
6550 if (generatedEl)
6551 ereport(ERROR,
6552 (errcode(ERRCODE_SYNTAX_ERROR),
6553 errmsg("conflicting or redundant options")));
6554 generatedEl = defel;
6555 }
6556 else
6557 elog(ERROR, "option \"%s\" not recognized",
6558 defel->defname);
6559 }
6560
6561 /*
6562 * Even if there is nothing to change here, we run all the checks. There
6563 * will be a subsequent ALTER SEQUENCE that relies on everything being
6564 * there.
6565 */
6566
6567 attrelation = table_open(AttributeRelationId, RowExclusiveLock);
6568 tuple = SearchSysCacheCopyAttName(RelationGetRelid(rel), colName);
6569 if (!HeapTupleIsValid(tuple))
6570 ereport(ERROR,
6571 (errcode(ERRCODE_UNDEFINED_COLUMN),
6572 errmsg("column \"%s\" of relation \"%s\" does not exist",
6573 colName, RelationGetRelationName(rel))));
6574
6575 attTup = (Form_pg_attribute) GETSTRUCT(tuple);
6576 attnum = attTup->attnum;
6577
6578 if (attnum <= 0)
6579 ereport(ERROR,
6580 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6581 errmsg("cannot alter system column \"%s\"",
6582 colName)));
6583
6584 if (!attTup->attidentity)
6585 ereport(ERROR,
6586 (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
6587 errmsg("column \"%s\" of relation \"%s\" is not an identity column",
6588 colName, RelationGetRelationName(rel))));
6589
6590 if (generatedEl)
6591 {
6592 attTup->attidentity = defGetInt32(generatedEl);
6593 CatalogTupleUpdate(attrelation, &tuple->t_self, tuple);
6594
6595 InvokeObjectPostAlterHook(RelationRelationId,
6596 RelationGetRelid(rel),
6597 attTup->attnum);
6598 ObjectAddressSubSet(address, RelationRelationId,
6599 RelationGetRelid(rel), attnum);
6600 }
6601 else
6602 address = InvalidObjectAddress;
6603
6604 heap_freetuple(tuple);
6605 table_close(attrelation, RowExclusiveLock);
6606
6607 return address;
6608}
6609
6610/*
6611 * ALTER TABLE ALTER COLUMN DROP IDENTITY
6612 *
6613 * Return the address of the affected column.
6614 */
6615static ObjectAddress
6616ATExecDropIdentity(Relation rel, const char *colName, bool missing_ok, LOCKMODE lockmode)
6617{
6618 HeapTuple tuple;
6619 Form_pg_attribute attTup;
6620 AttrNumber attnum;
6621 Relation attrelation;
6622 ObjectAddress address;
6623 Oid seqid;
6624 ObjectAddress seqaddress;
6625
6626 attrelation = table_open(AttributeRelationId, RowExclusiveLock);
6627 tuple = SearchSysCacheCopyAttName(RelationGetRelid(rel), colName);
6628 if (!HeapTupleIsValid(tuple))
6629 ereport(ERROR,
6630 (errcode(ERRCODE_UNDEFINED_COLUMN),
6631 errmsg("column \"%s\" of relation \"%s\" does not exist",
6632 colName, RelationGetRelationName(rel))));
6633
6634 attTup = (Form_pg_attribute) GETSTRUCT(tuple);
6635 attnum = attTup->attnum;
6636
6637 if (attnum <= 0)
6638 ereport(ERROR,
6639 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6640 errmsg("cannot alter system column \"%s\"",
6641 colName)));
6642
6643 if (!attTup->attidentity)
6644 {
6645 if (!missing_ok)
6646 ereport(ERROR,
6647 (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
6648 errmsg("column \"%s\" of relation \"%s\" is not an identity column",
6649 colName, RelationGetRelationName(rel))));
6650 else
6651 {
6652 ereport(NOTICE,
6653 (errmsg("column \"%s\" of relation \"%s\" is not an identity column, skipping",
6654 colName, RelationGetRelationName(rel))));
6655 heap_freetuple(tuple);
6656 table_close(attrelation, RowExclusiveLock);
6657 return InvalidObjectAddress;
6658 }
6659 }
6660
6661 attTup->attidentity = '\0';
6662 CatalogTupleUpdate(attrelation, &tuple->t_self, tuple);
6663
6664 InvokeObjectPostAlterHook(RelationRelationId,
6665 RelationGetRelid(rel),
6666 attTup->attnum);
6667 ObjectAddressSubSet(address, RelationRelationId,
6668 RelationGetRelid(rel), attnum);
6669 heap_freetuple(tuple);
6670
6671 table_close(attrelation, RowExclusiveLock);
6672
6673 /* drop the internal sequence */
6674 seqid = getOwnedSequence(RelationGetRelid(rel), attnum);
6675 deleteDependencyRecordsForClass(RelationRelationId, seqid,
6676 RelationRelationId, DEPENDENCY_INTERNAL);
6677 CommandCounterIncrement();
6678 seqaddress.classId = RelationRelationId;
6679 seqaddress.objectId = seqid;
6680 seqaddress.objectSubId = 0;
6681 performDeletion(&seqaddress, DROP_RESTRICT, PERFORM_DELETION_INTERNAL);
6682
6683 return address;
6684}
6685
6686/*
6687 * ALTER TABLE ALTER COLUMN SET STATISTICS
6688 */
6689static void
6690ATPrepSetStatistics(Relation rel, const char *colName, int16 colNum, Node *newValue, LOCKMODE lockmode)
6691{
6692 /*
6693 * We do our own permission checking because (a) we want to allow SET
6694 * STATISTICS on indexes (for expressional index columns), and (b) we want
6695 * to allow SET STATISTICS on system catalogs without requiring
6696 * allowSystemTableMods to be turned on.
6697 */
6698 if (rel->rd_rel->relkind != RELKIND_RELATION &&
6699 rel->rd_rel->relkind != RELKIND_MATVIEW &&
6700 rel->rd_rel->relkind != RELKIND_INDEX &&
6701 rel->rd_rel->relkind != RELKIND_PARTITIONED_INDEX &&
6702 rel->rd_rel->relkind != RELKIND_FOREIGN_TABLE &&
6703 rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
6704 ereport(ERROR,
6705 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
6706 errmsg("\"%s\" is not a table, materialized view, index, or foreign table",
6707 RelationGetRelationName(rel))));
6708
6709 /*
6710 * We allow referencing columns by numbers only for indexes, since table
6711 * column numbers could contain gaps if columns are later dropped.
6712 */
6713 if (rel->rd_rel->relkind != RELKIND_INDEX &&
6714 rel->rd_rel->relkind != RELKIND_PARTITIONED_INDEX &&
6715 !colName)
6716 ereport(ERROR,
6717 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6718 errmsg("cannot refer to non-index column by number")));
6719
6720 /* Permissions checks */
6721 if (!pg_class_ownercheck(RelationGetRelid(rel), GetUserId()))
6722 aclcheck_error(ACLCHECK_NOT_OWNER, get_relkind_objtype(rel->rd_rel->relkind),
6723 RelationGetRelationName(rel));
6724}
6725
6726/*
6727 * Return value is the address of the modified column
6728 */
6729static ObjectAddress
6730ATExecSetStatistics(Relation rel, const char *colName, int16 colNum, Node *newValue, LOCKMODE lockmode)
6731{
6732 int newtarget;
6733 Relation attrelation;
6734 HeapTuple tuple;
6735 Form_pg_attribute attrtuple;
6736 AttrNumber attnum;
6737 ObjectAddress address;
6738
6739 Assert(IsA(newValue, Integer));
6740 newtarget = intVal(newValue);
6741
6742 /*
6743 * Limit target to a sane range
6744 */
6745 if (newtarget < -1)
6746 {
6747 ereport(ERROR,
6748 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
6749 errmsg("statistics target %d is too low",
6750 newtarget)));
6751 }
6752 else if (newtarget > 10000)
6753 {
6754 newtarget = 10000;
6755 ereport(WARNING,
6756 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
6757 errmsg("lowering statistics target to %d",
6758 newtarget)));
6759 }
6760
6761 attrelation = table_open(AttributeRelationId, RowExclusiveLock);
6762
6763 if (colName)
6764 {
6765 tuple = SearchSysCacheCopyAttName(RelationGetRelid(rel), colName);
6766
6767 if (!HeapTupleIsValid(tuple))
6768 ereport(ERROR,
6769 (errcode(ERRCODE_UNDEFINED_COLUMN),
6770 errmsg("column \"%s\" of relation \"%s\" does not exist",
6771 colName, RelationGetRelationName(rel))));
6772 }
6773 else
6774 {
6775 tuple = SearchSysCacheCopyAttNum(RelationGetRelid(rel), colNum);
6776
6777 if (!HeapTupleIsValid(tuple))
6778 ereport(ERROR,
6779 (errcode(ERRCODE_UNDEFINED_COLUMN),
6780 errmsg("column number %d of relation \"%s\" does not exist",
6781 colNum, RelationGetRelationName(rel))));
6782 }
6783
6784 attrtuple = (Form_pg_attribute) GETSTRUCT(tuple);
6785
6786 attnum = attrtuple->attnum;
6787 if (attnum <= 0)
6788 ereport(ERROR,
6789 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6790 errmsg("cannot alter system column \"%s\"",
6791 colName)));
6792
6793 if (rel->rd_rel->relkind == RELKIND_INDEX ||
6794 rel->rd_rel->relkind == RELKIND_PARTITIONED_INDEX)
6795 {
6796 if (attnum > rel->rd_index->indnkeyatts)
6797 ereport(ERROR,
6798 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6799 errmsg("cannot alter statistics on included column \"%s\" of index \"%s\"",
6800 NameStr(attrtuple->attname), RelationGetRelationName(rel))));
6801 else if (rel->rd_index->indkey.values[attnum - 1] != 0)
6802 ereport(ERROR,
6803 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6804 errmsg("cannot alter statistics on non-expression column \"%s\" of index \"%s\"",
6805 NameStr(attrtuple->attname), RelationGetRelationName(rel)),
6806 errhint("Alter statistics on table column instead.")));
6807 }
6808
6809 attrtuple->attstattarget = newtarget;
6810
6811 CatalogTupleUpdate(attrelation, &tuple->t_self, tuple);
6812
6813 InvokeObjectPostAlterHook(RelationRelationId,
6814 RelationGetRelid(rel),
6815 attrtuple->attnum);
6816 ObjectAddressSubSet(address, RelationRelationId,
6817 RelationGetRelid(rel), attnum);
6818 heap_freetuple(tuple);
6819
6820 table_close(attrelation, RowExclusiveLock);
6821
6822 return address;
6823}
6824
6825/*
6826 * Return value is the address of the modified column
6827 */
6828static ObjectAddress
6829ATExecSetOptions(Relation rel, const char *colName, Node *options,
6830 bool isReset, LOCKMODE lockmode)
6831{
6832 Relation attrelation;
6833 HeapTuple tuple,
6834 newtuple;
6835 Form_pg_attribute attrtuple;
6836 AttrNumber attnum;
6837 Datum datum,
6838 newOptions;
6839 bool isnull;
6840 ObjectAddress address;
6841 Datum repl_val[Natts_pg_attribute];
6842 bool repl_null[Natts_pg_attribute];
6843 bool repl_repl[Natts_pg_attribute];
6844
6845 attrelation = table_open(AttributeRelationId, RowExclusiveLock);
6846
6847 tuple = SearchSysCacheAttName(RelationGetRelid(rel), colName);
6848
6849 if (!HeapTupleIsValid(tuple))
6850 ereport(ERROR,
6851 (errcode(ERRCODE_UNDEFINED_COLUMN),
6852 errmsg("column \"%s\" of relation \"%s\" does not exist",
6853 colName, RelationGetRelationName(rel))));
6854 attrtuple = (Form_pg_attribute) GETSTRUCT(tuple);
6855
6856 attnum = attrtuple->attnum;
6857 if (attnum <= 0)
6858 ereport(ERROR,
6859 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6860 errmsg("cannot alter system column \"%s\"",
6861 colName)));
6862
6863 /* Generate new proposed attoptions (text array) */
6864 datum = SysCacheGetAttr(ATTNAME, tuple, Anum_pg_attribute_attoptions,
6865 &isnull);
6866 newOptions = transformRelOptions(isnull ? (Datum) 0 : datum,
6867 castNode(List, options), NULL, NULL,
6868 false, isReset);
6869 /* Validate new options */
6870 (void) attribute_reloptions(newOptions, true);
6871
6872 /* Build new tuple. */
6873 memset(repl_null, false, sizeof(repl_null));
6874 memset(repl_repl, false, sizeof(repl_repl));
6875 if (newOptions != (Datum) 0)
6876 repl_val[Anum_pg_attribute_attoptions - 1] = newOptions;
6877 else
6878 repl_null[Anum_pg_attribute_attoptions - 1] = true;
6879 repl_repl[Anum_pg_attribute_attoptions - 1] = true;
6880 newtuple = heap_modify_tuple(tuple, RelationGetDescr(attrelation),
6881 repl_val, repl_null, repl_repl);
6882
6883 /* Update system catalog. */
6884 CatalogTupleUpdate(attrelation, &newtuple->t_self, newtuple);
6885
6886 InvokeObjectPostAlterHook(RelationRelationId,
6887 RelationGetRelid(rel),
6888 attrtuple->attnum);
6889 ObjectAddressSubSet(address, RelationRelationId,
6890 RelationGetRelid(rel), attnum);
6891
6892 heap_freetuple(newtuple);
6893
6894 ReleaseSysCache(tuple);
6895
6896 table_close(attrelation, RowExclusiveLock);
6897
6898 return address;
6899}
6900
6901/*
6902 * ALTER TABLE ALTER COLUMN SET STORAGE
6903 *
6904 * Return value is the address of the modified column
6905 */
6906static ObjectAddress
6907ATExecSetStorage(Relation rel, const char *colName, Node *newValue, LOCKMODE lockmode)
6908{
6909 char *storagemode;
6910 char newstorage;
6911 Relation attrelation;
6912 HeapTuple tuple;
6913 Form_pg_attribute attrtuple;
6914 AttrNumber attnum;
6915 ObjectAddress address;
6916
6917 Assert(IsA(newValue, String));
6918 storagemode = strVal(newValue);
6919
6920 if (pg_strcasecmp(storagemode, "plain") == 0)
6921 newstorage = 'p';
6922 else if (pg_strcasecmp(storagemode, "external") == 0)
6923 newstorage = 'e';
6924 else if (pg_strcasecmp(storagemode, "extended") == 0)
6925 newstorage = 'x';
6926 else if (pg_strcasecmp(storagemode, "main") == 0)
6927 newstorage = 'm';
6928 else
6929 {
6930 ereport(ERROR,
6931 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
6932 errmsg("invalid storage type \"%s\"",
6933 storagemode)));
6934 newstorage = 0; /* keep compiler quiet */
6935 }
6936
6937 attrelation = table_open(AttributeRelationId, RowExclusiveLock);
6938
6939 tuple = SearchSysCacheCopyAttName(RelationGetRelid(rel), colName);
6940
6941 if (!HeapTupleIsValid(tuple))
6942 ereport(ERROR,
6943 (errcode(ERRCODE_UNDEFINED_COLUMN),
6944 errmsg("column \"%s\" of relation \"%s\" does not exist",
6945 colName, RelationGetRelationName(rel))));
6946 attrtuple = (Form_pg_attribute) GETSTRUCT(tuple);
6947
6948 attnum = attrtuple->attnum;
6949 if (attnum <= 0)
6950 ereport(ERROR,
6951 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6952 errmsg("cannot alter system column \"%s\"",
6953 colName)));
6954
6955 /*
6956 * safety check: do not allow toasted storage modes unless column datatype
6957 * is TOAST-aware.
6958 */
6959 if (newstorage == 'p' || TypeIsToastable(attrtuple->atttypid))
6960 attrtuple->attstorage = newstorage;
6961 else
6962 ereport(ERROR,
6963 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6964 errmsg("column data type %s can only have storage PLAIN",
6965 format_type_be(attrtuple->atttypid))));
6966
6967 CatalogTupleUpdate(attrelation, &tuple->t_self, tuple);
6968
6969 InvokeObjectPostAlterHook(RelationRelationId,
6970 RelationGetRelid(rel),
6971 attrtuple->attnum);
6972
6973 heap_freetuple(tuple);
6974
6975 table_close(attrelation, RowExclusiveLock);
6976
6977 ObjectAddressSubSet(address, RelationRelationId,
6978 RelationGetRelid(rel), attnum);
6979 return address;
6980}
6981
6982
6983/*
6984 * ALTER TABLE DROP COLUMN
6985 *
6986 * DROP COLUMN cannot use the normal ALTER TABLE recursion mechanism,
6987 * because we have to decide at runtime whether to recurse or not depending
6988 * on whether attinhcount goes to zero or not. (We can't check this in a
6989 * static pre-pass because it won't handle multiple inheritance situations
6990 * correctly.)
6991 */
6992static void
6993ATPrepDropColumn(List **wqueue, Relation rel, bool recurse, bool recursing,
6994 AlterTableCmd *cmd, LOCKMODE lockmode)
6995{
6996 if (rel->rd_rel->reloftype && !recursing)
6997 ereport(ERROR,
6998 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
6999 errmsg("cannot drop column from typed table")));
7000
7001 if (rel->rd_rel->relkind == RELKIND_COMPOSITE_TYPE)
7002 ATTypedTableRecursion(wqueue, rel, cmd, lockmode);
7003
7004 if (recurse)
7005 cmd->subtype = AT_DropColumnRecurse;
7006}
7007
7008/*
7009 * Return value is the address of the dropped column.
7010 */
7011static ObjectAddress
7012ATExecDropColumn(List **wqueue, Relation rel, const char *colName,
7013 DropBehavior behavior,
7014 bool recurse, bool recursing,
7015 bool missing_ok, LOCKMODE lockmode)
7016{
7017 HeapTuple tuple;
7018 Form_pg_attribute targetatt;
7019 AttrNumber attnum;
7020 List *children;
7021 ObjectAddress object;
7022 bool is_expr;
7023
7024 /* At top level, permission check was done in ATPrepCmd, else do it */
7025 if (recursing)
7026 ATSimplePermissions(rel, ATT_TABLE | ATT_FOREIGN_TABLE);
7027
7028 /*
7029 * get the number of the attribute
7030 */
7031 tuple = SearchSysCacheAttName(RelationGetRelid(rel), colName);
7032 if (!HeapTupleIsValid(tuple))
7033 {
7034 if (!missing_ok)
7035 {
7036 ereport(ERROR,
7037 (errcode(ERRCODE_UNDEFINED_COLUMN),
7038 errmsg("column \"%s\" of relation \"%s\" does not exist",
7039 colName, RelationGetRelationName(rel))));
7040 }
7041 else
7042 {
7043 ereport(NOTICE,
7044 (errmsg("column \"%s\" of relation \"%s\" does not exist, skipping",
7045 colName, RelationGetRelationName(rel))));
7046 return InvalidObjectAddress;
7047 }
7048 }
7049 targetatt = (Form_pg_attribute) GETSTRUCT(tuple);
7050
7051 attnum = targetatt->attnum;
7052
7053 /* Can't drop a system attribute */
7054 if (attnum <= 0)
7055 ereport(ERROR,
7056 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
7057 errmsg("cannot drop system column \"%s\"",
7058 colName)));
7059
7060 /*
7061 * Don't drop inherited columns, unless recursing (presumably from a drop
7062 * of the parent column)
7063 */
7064 if (targetatt->attinhcount > 0 && !recursing)
7065 ereport(ERROR,
7066 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
7067 errmsg("cannot drop inherited column \"%s\"",
7068 colName)));
7069
7070 /*
7071 * Don't drop columns used in the partition key, either. (If we let this
7072 * go through, the key column's dependencies would cause a cascaded drop
7073 * of the whole table, which is surely not what the user expected.)
7074 */
7075 if (has_partition_attrs(rel,
7076 bms_make_singleton(attnum - FirstLowInvalidHeapAttributeNumber),
7077 &is_expr))
7078 ereport(ERROR,
7079 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
7080 errmsg("cannot drop column \"%s\" because it is part of the partition key of relation \"%s\"",
7081 colName, RelationGetRelationName(rel))));
7082
7083 ReleaseSysCache(tuple);
7084
7085 /*
7086 * Propagate to children as appropriate. Unlike most other ALTER
7087 * routines, we have to do this one level of recursion at a time; we can't
7088 * use find_all_inheritors to do it in one pass.
7089 */
7090 children = find_inheritance_children(RelationGetRelid(rel), lockmode);
7091
7092 if (children)
7093 {
7094 Relation attr_rel;
7095 ListCell *child;
7096
7097 /*
7098 * In case of a partitioned table, the column must be dropped from the
7099 * partitions as well.
7100 */
7101 if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE && !recurse)
7102 ereport(ERROR,
7103 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
7104 errmsg("cannot drop column from only the partitioned table when partitions exist"),
7105 errhint("Do not specify the ONLY keyword.")));
7106
7107 attr_rel = table_open(AttributeRelationId, RowExclusiveLock);
7108 foreach(child, children)
7109 {
7110 Oid childrelid = lfirst_oid(child);
7111 Relation childrel;
7112 Form_pg_attribute childatt;
7113
7114 /* find_inheritance_children already got lock */
7115 childrel = table_open(childrelid, NoLock);
7116 CheckTableNotInUse(childrel, "ALTER TABLE");
7117
7118 tuple = SearchSysCacheCopyAttName(childrelid, colName);
7119 if (!HeapTupleIsValid(tuple)) /* shouldn't happen */
7120 elog(ERROR, "cache lookup failed for attribute \"%s\" of relation %u",
7121 colName, childrelid);
7122 childatt = (Form_pg_attribute) GETSTRUCT(tuple);
7123
7124 if (childatt->attinhcount <= 0) /* shouldn't happen */
7125 elog(ERROR, "relation %u has non-inherited attribute \"%s\"",
7126 childrelid, colName);
7127
7128 if (recurse)
7129 {
7130 /*
7131 * If the child column has other definition sources, just
7132 * decrement its inheritance count; if not, recurse to delete
7133 * it.
7134 */
7135 if (childatt->attinhcount == 1 && !childatt->attislocal)
7136 {
7137 /* Time to delete this child column, too */
7138 ATExecDropColumn(wqueue, childrel, colName,
7139 behavior, true, true,
7140 false, lockmode);
7141 }
7142 else
7143 {
7144 /* Child column must survive my deletion */
7145 childatt->attinhcount--;
7146
7147 CatalogTupleUpdate(attr_rel, &tuple->t_self, tuple);
7148
7149 /* Make update visible */
7150 CommandCounterIncrement();
7151 }
7152 }
7153 else
7154 {
7155 /*
7156 * If we were told to drop ONLY in this table (no recursion),
7157 * we need to mark the inheritors' attributes as locally
7158 * defined rather than inherited.
7159 */
7160 childatt->attinhcount--;
7161 childatt->attislocal = true;
7162
7163 CatalogTupleUpdate(attr_rel, &tuple->t_self, tuple);
7164
7165 /* Make update visible */
7166 CommandCounterIncrement();
7167 }
7168
7169 heap_freetuple(tuple);
7170
7171 table_close(childrel, NoLock);
7172 }
7173 table_close(attr_rel, RowExclusiveLock);
7174 }
7175
7176 /*
7177 * Perform the actual column deletion
7178 */
7179 object.classId = RelationRelationId;
7180 object.objectId = RelationGetRelid(rel);
7181 object.objectSubId = attnum;
7182
7183 performDeletion(&object, behavior, 0);
7184
7185 return object;
7186}
7187
7188/*
7189 * ALTER TABLE ADD INDEX
7190 *
7191 * There is no such command in the grammar, but parse_utilcmd.c converts
7192 * UNIQUE and PRIMARY KEY constraints into AT_AddIndex subcommands. This lets
7193 * us schedule creation of the index at the appropriate time during ALTER.
7194 *
7195 * Return value is the address of the new index.
7196 */
7197static ObjectAddress
7198ATExecAddIndex(AlteredTableInfo *tab, Relation rel,
7199 IndexStmt *stmt, bool is_rebuild, LOCKMODE lockmode)
7200{
7201 bool check_rights;
7202 bool skip_build;
7203 bool quiet;
7204 ObjectAddress address;
7205
7206 Assert(IsA(stmt, IndexStmt));
7207 Assert(!stmt->concurrent);
7208
7209 /* The IndexStmt has already been through transformIndexStmt */
7210 Assert(stmt->transformed);
7211
7212 /* suppress schema rights check when rebuilding existing index */
7213 check_rights = !is_rebuild;
7214 /* skip index build if phase 3 will do it or we're reusing an old one */
7215 skip_build = tab->rewrite > 0 || OidIsValid(stmt->oldNode);
7216 /* suppress notices when rebuilding existing index */
7217 quiet = is_rebuild;
7218
7219 address = DefineIndex(RelationGetRelid(rel),
7220 stmt,
7221 InvalidOid, /* no predefined OID */
7222 InvalidOid, /* no parent index */
7223 InvalidOid, /* no parent constraint */
7224 true, /* is_alter_table */
7225 check_rights,
7226 false, /* check_not_in_use - we did it already */
7227 skip_build,
7228 quiet);
7229
7230 /*
7231 * If TryReuseIndex() stashed a relfilenode for us, we used it for the new
7232 * index instead of building from scratch. The DROP of the old edition of
7233 * this index will have scheduled the storage for deletion at commit, so
7234 * cancel that pending deletion.
7235 */
7236 if (OidIsValid(stmt->oldNode))
7237 {
7238 Relation irel = index_open(address.objectId, NoLock);
7239
7240 RelationPreserveStorage(irel->rd_node, true);
7241 index_close(irel, NoLock);
7242 }
7243
7244 return address;
7245}
7246
7247/*
7248 * ALTER TABLE ADD CONSTRAINT USING INDEX
7249 *
7250 * Returns the address of the new constraint.
7251 */
7252static ObjectAddress
7253ATExecAddIndexConstraint(AlteredTableInfo *tab, Relation rel,
7254 IndexStmt *stmt, LOCKMODE lockmode)
7255{
7256 Oid index_oid = stmt->indexOid;
7257 Relation indexRel;
7258 char *indexName;
7259 IndexInfo *indexInfo;
7260 char *constraintName;
7261 char constraintType;
7262 ObjectAddress address;
7263 bits16 flags;
7264
7265 Assert(IsA(stmt, IndexStmt));
7266 Assert(OidIsValid(index_oid));
7267 Assert(stmt->isconstraint);
7268
7269 /*
7270 * Doing this on partitioned tables is not a simple feature to implement,
7271 * so let's punt for now.
7272 */
7273 if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
7274 ereport(ERROR,
7275 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
7276 errmsg("ALTER TABLE / ADD CONSTRAINT USING INDEX is not supported on partitioned tables")));
7277
7278 indexRel = index_open(index_oid, AccessShareLock);
7279
7280 indexName = pstrdup(RelationGetRelationName(indexRel));
7281
7282 indexInfo = BuildIndexInfo(indexRel);
7283
7284 /* this should have been checked at parse time */
7285 if (!indexInfo->ii_Unique)
7286 elog(ERROR, "index \"%s\" is not unique", indexName);
7287
7288 /*
7289 * Determine name to assign to constraint. We require a constraint to
7290 * have the same name as the underlying index; therefore, use the index's
7291 * existing name as the default constraint name, and if the user
7292 * explicitly gives some other name for the constraint, rename the index
7293 * to match.
7294 */
7295 constraintName = stmt->idxname;
7296 if (constraintName == NULL)
7297 constraintName = indexName;
7298 else if (strcmp(constraintName, indexName) != 0)
7299 {
7300 ereport(NOTICE,
7301 (errmsg("ALTER TABLE / ADD CONSTRAINT USING INDEX will rename index \"%s\" to \"%s\"",
7302 indexName, constraintName)));
7303 RenameRelationInternal(index_oid, constraintName, false, true);
7304 }
7305
7306 /* Extra checks needed if making primary key */
7307 if (stmt->primary)
7308 index_check_primary_key(rel, indexInfo, true, stmt);
7309
7310 /* Note we currently don't support EXCLUSION constraints here */
7311 if (stmt->primary)
7312 constraintType = CONSTRAINT_PRIMARY;
7313 else
7314 constraintType = CONSTRAINT_UNIQUE;
7315
7316 /* Create the catalog entries for the constraint */
7317 flags = INDEX_CONSTR_CREATE_UPDATE_INDEX |
7318 INDEX_CONSTR_CREATE_REMOVE_OLD_DEPS |
7319 (stmt->initdeferred ? INDEX_CONSTR_CREATE_INIT_DEFERRED : 0) |
7320 (stmt->deferrable ? INDEX_CONSTR_CREATE_DEFERRABLE : 0) |
7321 (stmt->primary ? INDEX_CONSTR_CREATE_MARK_AS_PRIMARY : 0);
7322
7323 address = index_constraint_create(rel,
7324 index_oid,
7325 InvalidOid,
7326 indexInfo,
7327 constraintName,
7328 constraintType,
7329 flags,
7330 allowSystemTableMods,
7331 false); /* is_internal */
7332
7333 index_close(indexRel, NoLock);
7334
7335 return address;
7336}
7337
7338/*
7339 * ALTER TABLE ADD CONSTRAINT
7340 *
7341 * Return value is the address of the new constraint; if no constraint was
7342 * added, InvalidObjectAddress is returned.
7343 */
7344static ObjectAddress
7345ATExecAddConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
7346 Constraint *newConstraint, bool recurse, bool is_readd,
7347 LOCKMODE lockmode)
7348{
7349 ObjectAddress address = InvalidObjectAddress;
7350
7351 Assert(IsA(newConstraint, Constraint));
7352
7353 /*
7354 * Currently, we only expect to see CONSTR_CHECK and CONSTR_FOREIGN nodes
7355 * arriving here (see the preprocessing done in parse_utilcmd.c). Use a
7356 * switch anyway to make it easier to add more code later.
7357 */
7358 switch (newConstraint->contype)
7359 {
7360 case CONSTR_CHECK:
7361 address =
7362 ATAddCheckConstraint(wqueue, tab, rel,
7363 newConstraint, recurse, false, is_readd,
7364 lockmode);
7365 break;
7366
7367 case CONSTR_FOREIGN:
7368
7369 /*
7370 * Assign or validate constraint name
7371 */
7372 if (newConstraint->conname)
7373 {
7374 if (ConstraintNameIsUsed(CONSTRAINT_RELATION,
7375 RelationGetRelid(rel),
7376 newConstraint->conname))
7377 ereport(ERROR,
7378 (errcode(ERRCODE_DUPLICATE_OBJECT),
7379 errmsg("constraint \"%s\" for relation \"%s\" already exists",
7380 newConstraint->conname,
7381 RelationGetRelationName(rel))));
7382 }
7383 else
7384 newConstraint->conname =
7385 ChooseConstraintName(RelationGetRelationName(rel),
7386 ChooseForeignKeyConstraintNameAddition(newConstraint->fk_attrs),
7387 "fkey",
7388 RelationGetNamespace(rel),
7389 NIL);
7390
7391 address = ATAddForeignKeyConstraint(wqueue, tab, rel,
7392 newConstraint, InvalidOid,
7393 recurse, false,
7394 lockmode);
7395 break;
7396
7397 default:
7398 elog(ERROR, "unrecognized constraint type: %d",
7399 (int) newConstraint->contype);
7400 }
7401
7402 return address;
7403}
7404
7405/*
7406 * Generate the column-name portion of the constraint name for a new foreign
7407 * key given the list of column names that reference the referenced
7408 * table. This will be passed to ChooseConstraintName along with the parent
7409 * table name and the "fkey" suffix.
7410 *
7411 * We know that less than NAMEDATALEN characters will actually be used, so we
7412 * can truncate the result once we've generated that many.
7413 *
7414 * XXX see also ChooseExtendedStatisticNameAddition and
7415 * ChooseIndexNameAddition.
7416 */
7417static char *
7418ChooseForeignKeyConstraintNameAddition(List *colnames)
7419{
7420 char buf[NAMEDATALEN * 2];
7421 int buflen = 0;
7422 ListCell *lc;
7423
7424 buf[0] = '\0';
7425 foreach(lc, colnames)
7426 {
7427 const char *name = strVal(lfirst(lc));
7428
7429 if (buflen > 0)
7430 buf[buflen++] = '_'; /* insert _ between names */
7431
7432 /*
7433 * At this point we have buflen <= NAMEDATALEN. name should be less
7434 * than NAMEDATALEN already, but use strlcpy for paranoia.
7435 */
7436 strlcpy(buf + buflen, name, NAMEDATALEN);
7437 buflen += strlen(buf + buflen);
7438 if (buflen >= NAMEDATALEN)
7439 break;
7440 }
7441 return pstrdup(buf);
7442}
7443
7444/*
7445 * Add a check constraint to a single table and its children. Returns the
7446 * address of the constraint added to the parent relation, if one gets added,
7447 * or InvalidObjectAddress otherwise.
7448 *
7449 * Subroutine for ATExecAddConstraint.
7450 *
7451 * We must recurse to child tables during execution, rather than using
7452 * ALTER TABLE's normal prep-time recursion. The reason is that all the
7453 * constraints *must* be given the same name, else they won't be seen as
7454 * related later. If the user didn't explicitly specify a name, then
7455 * AddRelationNewConstraints would normally assign different names to the
7456 * child constraints. To fix that, we must capture the name assigned at
7457 * the parent table and pass that down.
7458 */
7459static ObjectAddress
7460ATAddCheckConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
7461 Constraint *constr, bool recurse, bool recursing,
7462 bool is_readd, LOCKMODE lockmode)
7463{
7464 List *newcons;
7465 ListCell *lcon;
7466 List *children;
7467 ListCell *child;
7468 ObjectAddress address = InvalidObjectAddress;
7469
7470 /* At top level, permission check was done in ATPrepCmd, else do it */
7471 if (recursing)
7472 ATSimplePermissions(rel, ATT_TABLE | ATT_FOREIGN_TABLE);
7473
7474 /*
7475 * Call AddRelationNewConstraints to do the work, making sure it works on
7476 * a copy of the Constraint so transformExpr can't modify the original. It
7477 * returns a list of cooked constraints.
7478 *
7479 * If the constraint ends up getting merged with a pre-existing one, it's
7480 * omitted from the returned list, which is what we want: we do not need
7481 * to do any validation work. That can only happen at child tables,
7482 * though, since we disallow merging at the top level.
7483 */
7484 newcons = AddRelationNewConstraints(rel, NIL,
7485 list_make1(copyObject(constr)),
7486 recursing | is_readd, /* allow_merge */
7487 !recursing, /* is_local */
7488 is_readd, /* is_internal */
7489 NULL); /* queryString not available
7490 * here */
7491
7492 /* we don't expect more than one constraint here */
7493 Assert(list_length(newcons) <= 1);
7494
7495 /* Add each to-be-validated constraint to Phase 3's queue */
7496 foreach(lcon, newcons)
7497 {
7498 CookedConstraint *ccon = (CookedConstraint *) lfirst(lcon);
7499
7500 if (!ccon->skip_validation)
7501 {
7502 NewConstraint *newcon;
7503
7504 newcon = (NewConstraint *) palloc0(sizeof(NewConstraint));
7505 newcon->name = ccon->name;
7506 newcon->contype = ccon->contype;
7507 newcon->qual = ccon->expr;
7508
7509 tab->constraints = lappend(tab->constraints, newcon);
7510 }
7511
7512 /* Save the actually assigned name if it was defaulted */
7513 if (constr->conname == NULL)
7514 constr->conname = ccon->name;
7515
7516 ObjectAddressSet(address, ConstraintRelationId, ccon->conoid);
7517 }
7518
7519 /* At this point we must have a locked-down name to use */
7520 Assert(constr->conname != NULL);
7521
7522 /* Advance command counter in case same table is visited multiple times */
7523 CommandCounterIncrement();
7524
7525 /*
7526 * If the constraint got merged with an existing constraint, we're done.
7527 * We mustn't recurse to child tables in this case, because they've
7528 * already got the constraint, and visiting them again would lead to an
7529 * incorrect value for coninhcount.
7530 */
7531 if (newcons == NIL)
7532 return address;
7533
7534 /*
7535 * If adding a NO INHERIT constraint, no need to find our children.
7536 */
7537 if (constr->is_no_inherit)
7538 return address;
7539
7540 /*
7541 * Propagate to children as appropriate. Unlike most other ALTER
7542 * routines, we have to do this one level of recursion at a time; we can't
7543 * use find_all_inheritors to do it in one pass.
7544 */
7545 children = find_inheritance_children(RelationGetRelid(rel), lockmode);
7546
7547 /*
7548 * Check if ONLY was specified with ALTER TABLE. If so, allow the
7549 * constraint creation only if there are no children currently. Error out
7550 * otherwise.
7551 */
7552 if (!recurse && children != NIL)
7553 ereport(ERROR,
7554 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
7555 errmsg("constraint must be added to child tables too")));
7556
7557 foreach(child, children)
7558 {
7559 Oid childrelid = lfirst_oid(child);
7560 Relation childrel;
7561 AlteredTableInfo *childtab;
7562
7563 /* find_inheritance_children already got lock */
7564 childrel = table_open(childrelid, NoLock);
7565 CheckTableNotInUse(childrel, "ALTER TABLE");
7566
7567 /* Find or create work queue entry for this table */
7568 childtab = ATGetQueueEntry(wqueue, childrel);
7569
7570 /* Recurse to child */
7571 ATAddCheckConstraint(wqueue, childtab, childrel,
7572 constr, recurse, true, is_readd, lockmode);
7573
7574 table_close(childrel, NoLock);
7575 }
7576
7577 return address;
7578}
7579
7580/*
7581 * Add a foreign-key constraint to a single table; return the new constraint's
7582 * address.
7583 *
7584 * Subroutine for ATExecAddConstraint. Must already hold exclusive
7585 * lock on the rel, and have done appropriate validity checks for it.
7586 * We do permissions checks here, however.
7587 *
7588 * When the referenced or referencing tables (or both) are partitioned,
7589 * multiple pg_constraint rows are required -- one for each partitioned table
7590 * and each partition on each side (fortunately, not one for every combination
7591 * thereof). We also need action triggers on each leaf partition on the
7592 * referenced side, and check triggers on each leaf partition on the
7593 * referencing side.
7594 */
7595static ObjectAddress
7596ATAddForeignKeyConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
7597 Constraint *fkconstraint, Oid parentConstr,
7598 bool recurse, bool recursing, LOCKMODE lockmode)
7599{
7600 Relation pkrel;
7601 int16 pkattnum[INDEX_MAX_KEYS];
7602 int16 fkattnum[INDEX_MAX_KEYS];
7603 Oid pktypoid[INDEX_MAX_KEYS];
7604 Oid fktypoid[INDEX_MAX_KEYS];
7605 Oid opclasses[INDEX_MAX_KEYS];
7606 Oid pfeqoperators[INDEX_MAX_KEYS];
7607 Oid ppeqoperators[INDEX_MAX_KEYS];
7608 Oid ffeqoperators[INDEX_MAX_KEYS];
7609 int i;
7610 int numfks,
7611 numpks;
7612 Oid indexOid;
7613 bool old_check_ok;
7614 ObjectAddress address;
7615 ListCell *old_pfeqop_item = list_head(fkconstraint->old_conpfeqop);
7616
7617 /*
7618 * Grab ShareRowExclusiveLock on the pk table, so that someone doesn't
7619 * delete rows out from under us.
7620 */
7621 if (OidIsValid(fkconstraint->old_pktable_oid))
7622 pkrel = table_open(fkconstraint->old_pktable_oid, ShareRowExclusiveLock);
7623 else
7624 pkrel = table_openrv(fkconstraint->pktable, ShareRowExclusiveLock);
7625
7626 /*
7627 * Validity checks (permission checks wait till we have the column
7628 * numbers)
7629 */
7630 if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
7631 {
7632 if (!recurse)
7633 ereport(ERROR,
7634 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
7635 errmsg("cannot use ONLY for foreign key on partitioned table \"%s\" referencing relation \"%s\"",
7636 RelationGetRelationName(rel),
7637 RelationGetRelationName(pkrel))));
7638 if (fkconstraint->skip_validation && !fkconstraint->initially_valid)
7639 ereport(ERROR,
7640 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
7641 errmsg("cannot add NOT VALID foreign key on partitioned table \"%s\" referencing relation \"%s\"",
7642 RelationGetRelationName(rel),
7643 RelationGetRelationName(pkrel)),
7644 errdetail("This feature is not yet supported on partitioned tables.")));
7645 }
7646
7647 if (pkrel->rd_rel->relkind != RELKIND_RELATION &&
7648 pkrel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
7649 ereport(ERROR,
7650 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
7651 errmsg("referenced relation \"%s\" is not a table",
7652 RelationGetRelationName(pkrel))));
7653
7654 if (!allowSystemTableMods && IsSystemRelation(pkrel))
7655 ereport(ERROR,
7656 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
7657 errmsg("permission denied: \"%s\" is a system catalog",
7658 RelationGetRelationName(pkrel))));
7659
7660 /*
7661 * References from permanent or unlogged tables to temp tables, and from
7662 * permanent tables to unlogged tables, are disallowed because the
7663 * referenced data can vanish out from under us. References from temp
7664 * tables to any other table type are also disallowed, because other
7665 * backends might need to run the RI triggers on the perm table, but they
7666 * can't reliably see tuples in the local buffers of other backends.
7667 */
7668 switch (rel->rd_rel->relpersistence)
7669 {
7670 case RELPERSISTENCE_PERMANENT:
7671 if (pkrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
7672 ereport(ERROR,
7673 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
7674 errmsg("constraints on permanent tables may reference only permanent tables")));
7675 break;
7676 case RELPERSISTENCE_UNLOGGED:
7677 if (pkrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT
7678 && pkrel->rd_rel->relpersistence != RELPERSISTENCE_UNLOGGED)
7679 ereport(ERROR,
7680 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
7681 errmsg("constraints on unlogged tables may reference only permanent or unlogged tables")));
7682 break;
7683 case RELPERSISTENCE_TEMP:
7684 if (pkrel->rd_rel->relpersistence != RELPERSISTENCE_TEMP)
7685 ereport(ERROR,
7686 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
7687 errmsg("constraints on temporary tables may reference only temporary tables")));
7688 if (!pkrel->rd_islocaltemp || !rel->rd_islocaltemp)
7689 ereport(ERROR,
7690 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
7691 errmsg("constraints on temporary tables must involve temporary tables of this session")));
7692 break;
7693 }
7694
7695 /*
7696 * Look up the referencing attributes to make sure they exist, and record
7697 * their attnums and type OIDs.
7698 */
7699 MemSet(pkattnum, 0, sizeof(pkattnum));
7700 MemSet(fkattnum, 0, sizeof(fkattnum));
7701 MemSet(pktypoid, 0, sizeof(pktypoid));
7702 MemSet(fktypoid, 0, sizeof(fktypoid));
7703 MemSet(opclasses, 0, sizeof(opclasses));
7704 MemSet(pfeqoperators, 0, sizeof(pfeqoperators));
7705 MemSet(ppeqoperators, 0, sizeof(ppeqoperators));
7706 MemSet(ffeqoperators, 0, sizeof(ffeqoperators));
7707
7708 numfks = transformColumnNameList(RelationGetRelid(rel),
7709 fkconstraint->fk_attrs,
7710 fkattnum, fktypoid);
7711
7712 /*
7713 * If the attribute list for the referenced table was omitted, lookup the
7714 * definition of the primary key and use it. Otherwise, validate the
7715 * supplied attribute list. In either case, discover the index OID and
7716 * index opclasses, and the attnums and type OIDs of the attributes.
7717 */
7718 if (fkconstraint->pk_attrs == NIL)
7719 {
7720 numpks = transformFkeyGetPrimaryKey(pkrel, &indexOid,
7721 &fkconstraint->pk_attrs,
7722 pkattnum, pktypoid,
7723 opclasses);
7724 }
7725 else
7726 {
7727 numpks = transformColumnNameList(RelationGetRelid(pkrel),
7728 fkconstraint->pk_attrs,
7729 pkattnum, pktypoid);
7730 /* Look for an index matching the column list */
7731 indexOid = transformFkeyCheckAttrs(pkrel, numpks, pkattnum,
7732 opclasses);
7733 }
7734
7735 /*
7736 * Now we can check permissions.
7737 */
7738 checkFkeyPermissions(pkrel, pkattnum, numpks);
7739
7740 /*
7741 * Check some things for generated columns.
7742 */
7743 for (i = 0; i < numfks; i++)
7744 {
7745 char attgenerated = TupleDescAttr(RelationGetDescr(rel), fkattnum[i] - 1)->attgenerated;
7746
7747 if (attgenerated)
7748 {
7749 /*
7750 * Check restrictions on UPDATE/DELETE actions, per SQL standard
7751 */
7752 if (fkconstraint->fk_upd_action == FKCONSTR_ACTION_SETNULL ||
7753 fkconstraint->fk_upd_action == FKCONSTR_ACTION_SETDEFAULT ||
7754 fkconstraint->fk_upd_action == FKCONSTR_ACTION_CASCADE)
7755 ereport(ERROR,
7756 (errcode(ERRCODE_SYNTAX_ERROR),
7757 errmsg("invalid %s action for foreign key constraint containing generated column",
7758 "ON UPDATE")));
7759 if (fkconstraint->fk_del_action == FKCONSTR_ACTION_SETNULL ||
7760 fkconstraint->fk_del_action == FKCONSTR_ACTION_SETDEFAULT)
7761 ereport(ERROR,
7762 (errcode(ERRCODE_SYNTAX_ERROR),
7763 errmsg("invalid %s action for foreign key constraint containing generated column",
7764 "ON DELETE")));
7765 }
7766 }
7767
7768 /*
7769 * Look up the equality operators to use in the constraint.
7770 *
7771 * Note that we have to be careful about the difference between the actual
7772 * PK column type and the opclass' declared input type, which might be
7773 * only binary-compatible with it. The declared opcintype is the right
7774 * thing to probe pg_amop with.
7775 */
7776 if (numfks != numpks)
7777 ereport(ERROR,
7778 (errcode(ERRCODE_INVALID_FOREIGN_KEY),
7779 errmsg("number of referencing and referenced columns for foreign key disagree")));
7780
7781 /*
7782 * On the strength of a previous constraint, we might avoid scanning
7783 * tables to validate this one. See below.
7784 */
7785 old_check_ok = (fkconstraint->old_conpfeqop != NIL);
7786 Assert(!old_check_ok || numfks == list_length(fkconstraint->old_conpfeqop));
7787
7788 for (i = 0; i < numpks; i++)
7789 {
7790 Oid pktype = pktypoid[i];
7791 Oid fktype = fktypoid[i];
7792 Oid fktyped;
7793 HeapTuple cla_ht;
7794 Form_pg_opclass cla_tup;
7795 Oid amid;
7796 Oid opfamily;
7797 Oid opcintype;
7798 Oid pfeqop;
7799 Oid ppeqop;
7800 Oid ffeqop;
7801 int16 eqstrategy;
7802 Oid pfeqop_right;
7803
7804 /* We need several fields out of the pg_opclass entry */
7805 cla_ht = SearchSysCache1(CLAOID, ObjectIdGetDatum(opclasses[i]));
7806 if (!HeapTupleIsValid(cla_ht))
7807 elog(ERROR, "cache lookup failed for opclass %u", opclasses[i]);
7808 cla_tup = (Form_pg_opclass) GETSTRUCT(cla_ht);
7809 amid = cla_tup->opcmethod;
7810 opfamily = cla_tup->opcfamily;
7811 opcintype = cla_tup->opcintype;
7812 ReleaseSysCache(cla_ht);
7813
7814 /*
7815 * Check it's a btree; currently this can never fail since no other
7816 * index AMs support unique indexes. If we ever did have other types
7817 * of unique indexes, we'd need a way to determine which operator
7818 * strategy number is equality. (Is it reasonable to insist that
7819 * every such index AM use btree's number for equality?)
7820 */
7821 if (amid != BTREE_AM_OID)
7822 elog(ERROR, "only b-tree indexes are supported for foreign keys");
7823 eqstrategy = BTEqualStrategyNumber;
7824
7825 /*
7826 * There had better be a primary equality operator for the index.
7827 * We'll use it for PK = PK comparisons.
7828 */
7829 ppeqop = get_opfamily_member(opfamily, opcintype, opcintype,
7830 eqstrategy);
7831
7832 if (!OidIsValid(ppeqop))
7833 elog(ERROR, "missing operator %d(%u,%u) in opfamily %u",
7834 eqstrategy, opcintype, opcintype, opfamily);
7835
7836 /*
7837 * Are there equality operators that take exactly the FK type? Assume
7838 * we should look through any domain here.
7839 */
7840 fktyped = getBaseType(fktype);
7841
7842 pfeqop = get_opfamily_member(opfamily, opcintype, fktyped,
7843 eqstrategy);
7844 if (OidIsValid(pfeqop))
7845 {
7846 pfeqop_right = fktyped;
7847 ffeqop = get_opfamily_member(opfamily, fktyped, fktyped,
7848 eqstrategy);
7849 }
7850 else
7851 {
7852 /* keep compiler quiet */
7853 pfeqop_right = InvalidOid;
7854 ffeqop = InvalidOid;
7855 }
7856
7857 if (!(OidIsValid(pfeqop) && OidIsValid(ffeqop)))
7858 {
7859 /*
7860 * Otherwise, look for an implicit cast from the FK type to the
7861 * opcintype, and if found, use the primary equality operator.
7862 * This is a bit tricky because opcintype might be a polymorphic
7863 * type such as ANYARRAY or ANYENUM; so what we have to test is
7864 * whether the two actual column types can be concurrently cast to
7865 * that type. (Otherwise, we'd fail to reject combinations such
7866 * as int[] and point[].)
7867 */
7868 Oid input_typeids[2];
7869 Oid target_typeids[2];
7870
7871 input_typeids[0] = pktype;
7872 input_typeids[1] = fktype;
7873 target_typeids[0] = opcintype;
7874 target_typeids[1] = opcintype;
7875 if (can_coerce_type(2, input_typeids, target_typeids,
7876 COERCION_IMPLICIT))
7877 {
7878 pfeqop = ffeqop = ppeqop;
7879 pfeqop_right = opcintype;
7880 }
7881 }
7882
7883 if (!(OidIsValid(pfeqop) && OidIsValid(ffeqop)))
7884 ereport(ERROR,
7885 (errcode(ERRCODE_DATATYPE_MISMATCH),
7886 errmsg("foreign key constraint \"%s\" cannot be implemented",
7887 fkconstraint->conname),
7888 errdetail("Key columns \"%s\" and \"%s\" "
7889 "are of incompatible types: %s and %s.",
7890 strVal(list_nth(fkconstraint->fk_attrs, i)),
7891 strVal(list_nth(fkconstraint->pk_attrs, i)),
7892 format_type_be(fktype),
7893 format_type_be(pktype))));
7894
7895 if (old_check_ok)
7896 {
7897 /*
7898 * When a pfeqop changes, revalidate the constraint. We could
7899 * permit intra-opfamily changes, but that adds subtle complexity
7900 * without any concrete benefit for core types. We need not
7901 * assess ppeqop or ffeqop, which RI_Initial_Check() does not use.
7902 */
7903 old_check_ok = (pfeqop == lfirst_oid(old_pfeqop_item));
7904 old_pfeqop_item = lnext(old_pfeqop_item);
7905 }
7906 if (old_check_ok)
7907 {
7908 Oid old_fktype;
7909 Oid new_fktype;
7910 CoercionPathType old_pathtype;
7911 CoercionPathType new_pathtype;
7912 Oid old_castfunc;
7913 Oid new_castfunc;
7914 Form_pg_attribute attr = TupleDescAttr(tab->oldDesc,
7915 fkattnum[i] - 1);
7916
7917 /*
7918 * Identify coercion pathways from each of the old and new FK-side
7919 * column types to the right (foreign) operand type of the pfeqop.
7920 * We may assume that pg_constraint.conkey is not changing.
7921 */
7922 old_fktype = attr->atttypid;
7923 new_fktype = fktype;
7924 old_pathtype = findFkeyCast(pfeqop_right, old_fktype,
7925 &old_castfunc);
7926 new_pathtype = findFkeyCast(pfeqop_right, new_fktype,
7927 &new_castfunc);
7928
7929 /*
7930 * Upon a change to the cast from the FK column to its pfeqop
7931 * operand, revalidate the constraint. For this evaluation, a
7932 * binary coercion cast is equivalent to no cast at all. While
7933 * type implementors should design implicit casts with an eye
7934 * toward consistency of operations like equality, we cannot
7935 * assume here that they have done so.
7936 *
7937 * A function with a polymorphic argument could change behavior
7938 * arbitrarily in response to get_fn_expr_argtype(). Therefore,
7939 * when the cast destination is polymorphic, we only avoid
7940 * revalidation if the input type has not changed at all. Given
7941 * just the core data types and operator classes, this requirement
7942 * prevents no would-be optimizations.
7943 *
7944 * If the cast converts from a base type to a domain thereon, then
7945 * that domain type must be the opcintype of the unique index.
7946 * Necessarily, the primary key column must then be of the domain
7947 * type. Since the constraint was previously valid, all values on
7948 * the foreign side necessarily exist on the primary side and in
7949 * turn conform to the domain. Consequently, we need not treat
7950 * domains specially here.
7951 *
7952 * Since we require that all collations share the same notion of
7953 * equality (which they do, because texteq reduces to bitwise
7954 * equality), we don't compare collation here.
7955 *
7956 * We need not directly consider the PK type. It's necessarily
7957 * binary coercible to the opcintype of the unique index column,
7958 * and ri_triggers.c will only deal with PK datums in terms of
7959 * that opcintype. Changing the opcintype also changes pfeqop.
7960 */
7961 old_check_ok = (new_pathtype == old_pathtype &&
7962 new_castfunc == old_castfunc &&
7963 (!IsPolymorphicType(pfeqop_right) ||
7964 new_fktype == old_fktype));
7965 }
7966
7967 pfeqoperators[i] = pfeqop;
7968 ppeqoperators[i] = ppeqop;
7969 ffeqoperators[i] = ffeqop;
7970 }
7971
7972 /*
7973 * Create all the constraint and trigger objects, recursing to partitions
7974 * as necessary. First handle the referenced side.
7975 */
7976 address = addFkRecurseReferenced(wqueue, fkconstraint, rel, pkrel,
7977 indexOid,
7978 InvalidOid, /* no parent constraint */
7979 numfks,
7980 pkattnum,
7981 fkattnum,
7982 pfeqoperators,
7983 ppeqoperators,
7984 ffeqoperators,
7985 old_check_ok);
7986
7987 /* Now handle the referencing side. */
7988 addFkRecurseReferencing(wqueue, fkconstraint, rel, pkrel,
7989 indexOid,
7990 address.objectId,
7991 numfks,
7992 pkattnum,
7993 fkattnum,
7994 pfeqoperators,
7995 ppeqoperators,
7996 ffeqoperators,
7997 old_check_ok,
7998 lockmode);
7999
8000 /*
8001 * Done. Close pk table, but keep lock until we've committed.
8002 */
8003 table_close(pkrel, NoLock);
8004
8005 return address;
8006}
8007
8008/*
8009 * addFkRecurseReferenced
8010 * subroutine for ATAddForeignKeyConstraint; recurses on the referenced
8011 * side of the constraint
8012 *
8013 * Create pg_constraint rows for the referenced side of the constraint,
8014 * referencing the parent of the referencing side; also create action triggers
8015 * on leaf partitions. If the table is partitioned, recurse to handle each
8016 * partition.
8017 *
8018 * wqueue is the ALTER TABLE work queue; can be NULL when not running as part
8019 * of an ALTER TABLE sequence.
8020 * fkconstraint is the constraint being added.
8021 * rel is the root referencing relation.
8022 * pkrel is the referenced relation; might be a partition, if recursing.
8023 * indexOid is the OID of the index (on pkrel) implementing this constraint.
8024 * parentConstr is the OID of a parent constraint; InvalidOid if this is a
8025 * top-level constraint.
8026 * numfks is the number of columns in the foreign key
8027 * pkattnum is the attnum array of referenced attributes.
8028 * fkattnum is the attnum array of referencing attributes.
8029 * pf/pp/ffeqoperators are OID array of operators between columns.
8030 * old_check_ok signals that this constraint replaces an existing one that
8031 * was already validated (thus this one doesn't need validation).
8032 */
8033static ObjectAddress
8034addFkRecurseReferenced(List **wqueue, Constraint *fkconstraint, Relation rel,
8035 Relation pkrel, Oid indexOid, Oid parentConstr,
8036 int numfks,
8037 int16 *pkattnum, int16 *fkattnum, Oid *pfeqoperators,
8038 Oid *ppeqoperators, Oid *ffeqoperators, bool old_check_ok)
8039{
8040 ObjectAddress address;
8041 Oid constrOid;
8042 char *conname;
8043 bool conislocal;
8044 int coninhcount;
8045 bool connoinherit;
8046
8047 /*
8048 * Verify relkind for each referenced partition. At the top level, this
8049 * is redundant with a previous check, but we need it when recursing.
8050 */
8051 if (pkrel->rd_rel->relkind != RELKIND_RELATION &&
8052 pkrel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE)
8053 ereport(ERROR,
8054 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
8055 errmsg("referenced relation \"%s\" is not a table",
8056 RelationGetRelationName(pkrel))));
8057
8058 /*
8059 * Caller supplies us with a constraint name; however, it may be used in
8060 * this partition, so come up with a different one in that case.
8061 */
8062 if (ConstraintNameIsUsed(CONSTRAINT_RELATION,
8063 RelationGetRelid(rel),
8064 fkconstraint->conname))
8065 conname = ChooseConstraintName(RelationGetRelationName(rel),
8066 ChooseForeignKeyConstraintNameAddition(fkconstraint->fk_attrs),
8067 "fkey",
8068 RelationGetNamespace(rel), NIL);
8069 else
8070 conname = fkconstraint->conname;
8071
8072 if (OidIsValid(parentConstr))
8073 {
8074 conislocal = false;
8075 coninhcount = 1;
8076 connoinherit = false;
8077 }
8078 else
8079 {
8080 conislocal = true;
8081 coninhcount = 0;
8082
8083 /*
8084 * always inherit for partitioned tables, never for legacy inheritance
8085 */
8086 connoinherit = rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE;
8087 }
8088
8089 /*
8090 * Record the FK constraint in pg_constraint.
8091 */
8092 constrOid = CreateConstraintEntry(conname,
8093 RelationGetNamespace(rel),
8094 CONSTRAINT_FOREIGN,
8095 fkconstraint->deferrable,
8096 fkconstraint->initdeferred,
8097 fkconstraint->initially_valid,
8098 parentConstr,
8099 RelationGetRelid(rel),
8100 fkattnum,
8101 numfks,
8102 numfks,
8103 InvalidOid, /* not a domain constraint */
8104 indexOid,
8105 RelationGetRelid(pkrel),
8106 pkattnum,
8107 pfeqoperators,
8108 ppeqoperators,
8109 ffeqoperators,
8110 numfks,
8111 fkconstraint->fk_upd_action,
8112 fkconstraint->fk_del_action,
8113 fkconstraint->fk_matchtype,
8114 NULL, /* no exclusion constraint */
8115 NULL, /* no check constraint */
8116 NULL,
8117 conislocal, /* islocal */
8118 coninhcount, /* inhcount */
8119 connoinherit, /* conNoInherit */
8120 false); /* is_internal */
8121
8122 ObjectAddressSet(address, ConstraintRelationId, constrOid);
8123
8124 /*
8125 * Mark the child constraint as part of the parent constraint; it must not
8126 * be dropped on its own. (This constraint is deleted when the partition
8127 * is detached, but a special check needs to occur that the partition
8128 * contains no referenced values.)
8129 */
8130 if (OidIsValid(parentConstr))
8131 {
8132 ObjectAddress referenced;
8133
8134 ObjectAddressSet(referenced, ConstraintRelationId, parentConstr);
8135 recordDependencyOn(&address, &referenced, DEPENDENCY_INTERNAL);
8136 }
8137
8138 /* make new constraint visible, in case we add more */
8139 CommandCounterIncrement();
8140
8141 /*
8142 * If the referenced table is a plain relation, create the action triggers
8143 * that enforce the constraint.
8144 */
8145 if (pkrel->rd_rel->relkind == RELKIND_RELATION)
8146 {
8147 createForeignKeyActionTriggers(rel, RelationGetRelid(pkrel),
8148 fkconstraint,
8149 constrOid, indexOid);
8150 }
8151
8152 /*
8153 * If the referenced table is partitioned, recurse on ourselves to handle
8154 * each partition. We need one pg_constraint row created for each
8155 * partition in addition to the pg_constraint row for the parent table.
8156 */
8157 if (pkrel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
8158 {
8159 PartitionDesc pd = RelationGetPartitionDesc(pkrel);
8160
8161 for (int i = 0; i < pd->nparts; i++)
8162 {
8163 Relation partRel;
8164 AttrNumber *map;
8165 AttrNumber *mapped_pkattnum;
8166 Oid partIndexId;
8167
8168 partRel = table_open(pd->oids[i], ShareRowExclusiveLock);
8169
8170 /*
8171 * Map the attribute numbers in the referenced side of the FK
8172 * definition to match the partition's column layout.
8173 */
8174 map = convert_tuples_by_name_map_if_req(RelationGetDescr(partRel),
8175 RelationGetDescr(pkrel),
8176 gettext_noop("could not convert row type"));
8177 if (map)
8178 {
8179 mapped_pkattnum = palloc(sizeof(AttrNumber) * numfks);
8180 for (int j = 0; j < numfks; j++)
8181 mapped_pkattnum[j] = map[pkattnum[j] - 1];
8182 }
8183 else
8184 mapped_pkattnum = pkattnum;
8185
8186 /* do the deed */
8187 partIndexId = index_get_partition(partRel, indexOid);
8188 if (!OidIsValid(partIndexId))
8189 elog(ERROR, "index for %u not found in partition %s",
8190 indexOid, RelationGetRelationName(partRel));
8191 addFkRecurseReferenced(wqueue, fkconstraint, rel, partRel,
8192 partIndexId, constrOid, numfks,
8193 mapped_pkattnum, fkattnum,
8194 pfeqoperators, ppeqoperators, ffeqoperators,
8195 old_check_ok);
8196
8197 /* Done -- clean up (but keep the lock) */
8198 table_close(partRel, NoLock);
8199 if (map)
8200 {
8201 pfree(mapped_pkattnum);
8202 pfree(map);
8203 }
8204 }
8205 }
8206
8207 return address;
8208}
8209
8210/*
8211 * addFkRecurseReferencing
8212 * subroutine for ATAddForeignKeyConstraint and CloneFkReferencing
8213 *
8214 * If the referencing relation is a plain relation, create the necessary check
8215 * triggers that implement the constraint, and set up for Phase 3 constraint
8216 * verification. If the referencing relation is a partitioned table, then
8217 * we create a pg_constraint row for it and recurse on this routine for each
8218 * partition.
8219 *
8220 * We assume that the referenced relation is locked against concurrent
8221 * deletions. If it's a partitioned relation, every partition must be so
8222 * locked.
8223 *
8224 * wqueue is the ALTER TABLE work queue; can be NULL when not running as part
8225 * of an ALTER TABLE sequence.
8226 * fkconstraint is the constraint being added.
8227 * rel is the referencing relation; might be a partition, if recursing.
8228 * pkrel is the root referenced relation.
8229 * indexOid is the OID of the index (on pkrel) implementing this constraint.
8230 * parentConstr is the OID of the parent constraint (there is always one).
8231 * numfks is the number of columns in the foreign key
8232 * pkattnum is the attnum array of referenced attributes.
8233 * fkattnum is the attnum array of referencing attributes.
8234 * pf/pp/ffeqoperators are OID array of operators between columns.
8235 * old_check_ok signals that this constraint replaces an existing one that
8236 * was already validated (thus this one doesn't need validation).
8237 * lockmode is the lockmode to acquire on partitions when recursing.
8238 */
8239static void
8240addFkRecurseReferencing(List **wqueue, Constraint *fkconstraint, Relation rel,
8241 Relation pkrel, Oid indexOid, Oid parentConstr,
8242 int numfks, int16 *pkattnum, int16 *fkattnum,
8243 Oid *pfeqoperators, Oid *ppeqoperators, Oid *ffeqoperators,
8244 bool old_check_ok, LOCKMODE lockmode)
8245{
8246 AssertArg(OidIsValid(parentConstr));
8247
8248 if (rel->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
8249 ereport(ERROR,
8250 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
8251 errmsg("foreign key constraints are not supported on foreign tables")));
8252
8253 /*
8254 * If the referencing relation is a plain table, add the check triggers to
8255 * it and, if necessary, schedule it to be checked in Phase 3.
8256 *
8257 * If the relation is partitioned, drill down to do it to its partitions.
8258 */
8259 if (rel->rd_rel->relkind == RELKIND_RELATION)
8260 {
8261 createForeignKeyCheckTriggers(RelationGetRelid(rel),
8262 RelationGetRelid(pkrel),
8263 fkconstraint,
8264 parentConstr,
8265 indexOid);
8266
8267 /*
8268 * Tell Phase 3 to check that the constraint is satisfied by existing
8269 * rows. We can skip this during table creation, when requested
8270 * explicitly by specifying NOT VALID in an ADD FOREIGN KEY command,
8271 * and when we're recreating a constraint following a SET DATA TYPE
8272 * operation that did not impugn its validity.
8273 */
8274 if (wqueue && !old_check_ok && !fkconstraint->skip_validation)
8275 {
8276 NewConstraint *newcon;
8277 AlteredTableInfo *tab;
8278
8279 tab = ATGetQueueEntry(wqueue, rel);
8280
8281 newcon = (NewConstraint *) palloc0(sizeof(NewConstraint));
8282 newcon->name = get_constraint_name(parentConstr);
8283 newcon->contype = CONSTR_FOREIGN;
8284 newcon->refrelid = RelationGetRelid(pkrel);
8285 newcon->refindid = indexOid;
8286 newcon->conid = parentConstr;
8287 newcon->qual = (Node *) fkconstraint;
8288
8289 tab->constraints = lappend(tab->constraints, newcon);
8290 }
8291 }
8292 else if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
8293 {
8294 PartitionDesc pd = RelationGetPartitionDesc(rel);
8295
8296 /*
8297 * Recurse to take appropriate action on each partition; either we
8298 * find an existing constraint to reparent to ours, or we create a new
8299 * one.
8300 */
8301 for (int i = 0; i < pd->nparts; i++)
8302 {
8303 Oid partitionId = pd->oids[i];
8304 Relation partition = table_open(partitionId, lockmode);
8305 List *partFKs;
8306 AttrNumber *attmap;
8307 AttrNumber mapped_fkattnum[INDEX_MAX_KEYS];
8308 bool attached;
8309 char *conname;
8310 Oid constrOid;
8311 ObjectAddress address,
8312 referenced;
8313 ListCell *cell;
8314
8315 CheckTableNotInUse(partition, "ALTER TABLE");
8316
8317 attmap = convert_tuples_by_name_map(RelationGetDescr(partition),
8318 RelationGetDescr(rel),
8319 gettext_noop("could not convert row type"));
8320 for (int j = 0; j < numfks; j++)
8321 mapped_fkattnum[j] = attmap[fkattnum[j] - 1];
8322
8323 /* Check whether an existing constraint can be repurposed */
8324 partFKs = copyObject(RelationGetFKeyList(partition));
8325 attached = false;
8326 foreach(cell, partFKs)
8327 {
8328 ForeignKeyCacheInfo *fk;
8329
8330 fk = lfirst_node(ForeignKeyCacheInfo, cell);
8331 if (tryAttachPartitionForeignKey(fk,
8332 partitionId,
8333 parentConstr,
8334 numfks,
8335 mapped_fkattnum,
8336 pkattnum,
8337 pfeqoperators))
8338 {
8339 attached = true;
8340 break;
8341 }
8342 }
8343 if (attached)
8344 {
8345 table_close(partition, NoLock);
8346 continue;
8347 }
8348
8349 /*
8350 * No luck finding a good constraint to reuse; create our own.
8351 */
8352 if (ConstraintNameIsUsed(CONSTRAINT_RELATION,
8353 RelationGetRelid(partition),
8354 fkconstraint->conname))
8355 conname = ChooseConstraintName(RelationGetRelationName(partition),
8356 ChooseForeignKeyConstraintNameAddition(fkconstraint->fk_attrs),
8357 "fkey",
8358 RelationGetNamespace(partition), NIL);
8359 else
8360 conname = fkconstraint->conname;
8361 constrOid =
8362 CreateConstraintEntry(conname,
8363 RelationGetNamespace(partition),
8364 CONSTRAINT_FOREIGN,
8365 fkconstraint->deferrable,
8366 fkconstraint->initdeferred,
8367 fkconstraint->initially_valid,
8368 parentConstr,
8369 partitionId,
8370 mapped_fkattnum,
8371 numfks,
8372 numfks,
8373 InvalidOid,
8374 indexOid,
8375 RelationGetRelid(pkrel),
8376 pkattnum,
8377 pfeqoperators,
8378 ppeqoperators,
8379 ffeqoperators,
8380 numfks,
8381 fkconstraint->fk_upd_action,
8382 fkconstraint->fk_del_action,
8383 fkconstraint->fk_matchtype,
8384 NULL,
8385 NULL,
8386 NULL,
8387 false,
8388 1,
8389 false,
8390 false);
8391
8392 /*
8393 * Give this constraint partition-type dependencies on the parent
8394 * constraint as well as the table.
8395 */
8396 ObjectAddressSet(address, ConstraintRelationId, constrOid);
8397 ObjectAddressSet(referenced, ConstraintRelationId, parentConstr);
8398 recordDependencyOn(&address, &referenced, DEPENDENCY_PARTITION_PRI);
8399 ObjectAddressSet(referenced, RelationRelationId, partitionId);
8400 recordDependencyOn(&address, &referenced, DEPENDENCY_PARTITION_SEC);
8401
8402 /* Make all this visible before recursing */
8403 CommandCounterIncrement();
8404
8405 /* call ourselves to finalize the creation and we're done */
8406 addFkRecurseReferencing(wqueue, fkconstraint, partition, pkrel,
8407 indexOid,
8408 constrOid,
8409 numfks,
8410 pkattnum,
8411 mapped_fkattnum,
8412 pfeqoperators,
8413 ppeqoperators,
8414 ffeqoperators,
8415 old_check_ok,
8416 lockmode);
8417
8418 table_close(partition, NoLock);
8419 }
8420 }
8421}
8422
8423/*
8424 * CloneForeignKeyConstraints
8425 * Clone foreign keys from a partitioned table to a newly acquired
8426 * partition.
8427 *
8428 * partitionRel is a partition of parentRel, so we can be certain that it has
8429 * the same columns with the same datatypes. The columns may be in different
8430 * order, though.
8431 *
8432 * wqueue must be passed to set up phase 3 constraint checking, unless the
8433 * referencing-side partition is known to be empty (such as in CREATE TABLE /
8434 * PARTITION OF).
8435 */
8436static void
8437CloneForeignKeyConstraints(List **wqueue, Relation parentRel,
8438 Relation partitionRel)
8439{
8440 /* This only works for declarative partitioning */
8441 Assert(parentRel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE);
8442
8443 /*
8444 * Clone constraints for which the parent is on the referenced side.
8445 */
8446 CloneFkReferenced(parentRel, partitionRel);
8447
8448 /*
8449 * Now clone constraints where the parent is on the referencing side.
8450 */
8451 CloneFkReferencing(wqueue, parentRel, partitionRel);
8452}
8453
8454/*
8455 * CloneFkReferenced
8456 * Subroutine for CloneForeignKeyConstraints
8457 *
8458 * Find all the FKs that have the parent relation on the referenced side;
8459 * clone those constraints to the given partition. This is to be called
8460 * when the partition is being created or attached.
8461 *
8462 * This recurses to partitions, if the relation being attached is partitioned.
8463 * Recursion is done by calling addFkRecurseReferenced.
8464 */
8465static void
8466CloneFkReferenced(Relation parentRel, Relation partitionRel)
8467{
8468 Relation pg_constraint;
8469 AttrNumber *attmap;
8470 ListCell *cell;
8471 SysScanDesc scan;
8472 ScanKeyData key[2];
8473 HeapTuple tuple;
8474 List *clone = NIL;
8475
8476 /*
8477 * Search for any constraints where this partition is in the referenced
8478 * side. However, we must ignore any constraint whose parent constraint
8479 * is also going to be cloned, to avoid duplicates. So do it in two
8480 * steps: first construct the list of constraints to clone, then go over
8481 * that list cloning those whose parents are not in the list. (We must
8482 * not rely on the parent being seen first, since the catalog scan could
8483 * return children first.)
8484 */
8485 pg_constraint = table_open(ConstraintRelationId, RowShareLock);
8486 ScanKeyInit(&key[0],
8487 Anum_pg_constraint_confrelid, BTEqualStrategyNumber,
8488 F_OIDEQ, ObjectIdGetDatum(RelationGetRelid(parentRel)));
8489 ScanKeyInit(&key[1],
8490 Anum_pg_constraint_contype, BTEqualStrategyNumber,
8491 F_CHAREQ, CharGetDatum(CONSTRAINT_FOREIGN));
8492 /* This is a seqscan, as we don't have a usable index ... */
8493 scan = systable_beginscan(pg_constraint, InvalidOid, true,
8494 NULL, 2, key);
8495 while ((tuple = systable_getnext(scan)) != NULL)
8496 {
8497 Form_pg_constraint constrForm = (Form_pg_constraint) GETSTRUCT(tuple);
8498
8499 /* Only try to clone the top-level constraint; skip child ones. */
8500 if (constrForm->conparentid != InvalidOid)
8501 continue;
8502
8503 clone = lappend_oid(clone, constrForm->oid);
8504 }
8505 systable_endscan(scan);
8506 table_close(pg_constraint, RowShareLock);
8507
8508 attmap = convert_tuples_by_name_map(RelationGetDescr(partitionRel),
8509 RelationGetDescr(parentRel),
8510 gettext_noop("could not convert row type"));
8511 foreach(cell, clone)
8512 {
8513 Oid constrOid = lfirst_oid(cell);
8514 Form_pg_constraint constrForm;
8515 Relation fkRel;
8516 Oid indexOid;
8517 Oid partIndexId;
8518 int numfks;
8519 AttrNumber conkey[INDEX_MAX_KEYS];
8520 AttrNumber mapped_confkey[INDEX_MAX_KEYS];
8521 AttrNumber confkey[INDEX_MAX_KEYS];
8522 Oid conpfeqop[INDEX_MAX_KEYS];
8523 Oid conppeqop[INDEX_MAX_KEYS];
8524 Oid conffeqop[INDEX_MAX_KEYS];
8525 Constraint *fkconstraint;
8526
8527 tuple = SearchSysCache1(CONSTROID, constrOid);
8528 if (!HeapTupleIsValid(tuple))
8529 elog(ERROR, "cache lookup failed for constraint %u", constrOid);
8530 constrForm = (Form_pg_constraint) GETSTRUCT(tuple);
8531
8532 /*
8533 * Because we're only expanding the key space at the referenced side,
8534 * we don't need to prevent any operation in the referencing table, so
8535 * AccessShareLock suffices (assumes that dropping the constraint
8536 * acquires AEL).
8537 */
8538 fkRel = table_open(constrForm->conrelid, AccessShareLock);
8539
8540 indexOid = constrForm->conindid;
8541 DeconstructFkConstraintRow(tuple,
8542 &numfks,
8543 conkey,
8544 confkey,
8545 conpfeqop,
8546 conppeqop,
8547 conffeqop);
8548 for (int i = 0; i < numfks; i++)
8549 mapped_confkey[i] = attmap[confkey[i] - 1];
8550
8551 fkconstraint = makeNode(Constraint);
8552 /* for now this is all we need */
8553 fkconstraint->conname = NameStr(constrForm->conname);
8554 fkconstraint->fk_upd_action = constrForm->confupdtype;
8555 fkconstraint->fk_del_action = constrForm->confdeltype;
8556 fkconstraint->deferrable = constrForm->condeferrable;
8557 fkconstraint->initdeferred = constrForm->condeferred;
8558 fkconstraint->initially_valid = true;
8559 fkconstraint->fk_matchtype = constrForm->confmatchtype;
8560
8561 /* set up colnames that are used to generate the constraint name */
8562 for (int i = 0; i < numfks; i++)
8563 {
8564 Form_pg_attribute att;
8565
8566 att = TupleDescAttr(RelationGetDescr(fkRel),
8567 conkey[i] - 1);
8568 fkconstraint->fk_attrs = lappend(fkconstraint->fk_attrs,
8569 makeString(NameStr(att->attname)));
8570 }
8571
8572 /*
8573 * Add the new foreign key constraint pointing to the new partition.
8574 * Because this new partition appears in the referenced side of the
8575 * constraint, we don't need to set up for Phase 3 check.
8576 */
8577 partIndexId = index_get_partition(partitionRel, indexOid);
8578 if (!OidIsValid(partIndexId))
8579 elog(ERROR, "index for %u not found in partition %s",
8580 indexOid, RelationGetRelationName(partitionRel));
8581 addFkRecurseReferenced(NULL,
8582 fkconstraint,
8583 fkRel,
8584 partitionRel,
8585 partIndexId,
8586 constrOid,
8587 numfks,
8588 mapped_confkey,
8589 conkey,
8590 conpfeqop,
8591 conppeqop,
8592 conffeqop,
8593 true);
8594
8595 table_close(fkRel, NoLock);
8596 ReleaseSysCache(tuple);
8597 }
8598}
8599
8600/*
8601 * CloneFkReferencing
8602 * Subroutine for CloneForeignKeyConstraints
8603 *
8604 * For each FK constraint of the parent relation in the given list, find an
8605 * equivalent constraint in its partition relation that can be reparented;
8606 * if one cannot be found, create a new constraint in the partition as its
8607 * child.
8608 *
8609 * If wqueue is given, it is used to set up phase-3 verification for each
8610 * cloned constraint; if omitted, we assume that such verification is not
8611 * needed (example: the partition is being created anew).
8612 */
8613static void
8614CloneFkReferencing(List **wqueue, Relation parentRel, Relation partRel)
8615{
8616 AttrNumber *attmap;
8617 List *partFKs;
8618 List *clone = NIL;
8619 ListCell *cell;
8620
8621 /* obtain a list of constraints that we need to clone */
8622 foreach(cell, RelationGetFKeyList(parentRel))
8623 {
8624 ForeignKeyCacheInfo *fk = lfirst(cell);
8625
8626 clone = lappend_oid(clone, fk->conoid);
8627 }
8628
8629 /*
8630 * Silently do nothing if there's nothing to do. In particular, this
8631 * avoids throwing a spurious error for foreign tables.
8632 */
8633 if (clone == NIL)
8634 return;
8635
8636 if (partRel->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
8637 ereport(ERROR,
8638 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
8639 errmsg("foreign key constraints are not supported on foreign tables")));
8640
8641 /*
8642 * The constraint key may differ, if the columns in the partition are
8643 * different. This map is used to convert them.
8644 */
8645 attmap = convert_tuples_by_name_map(RelationGetDescr(partRel),
8646 RelationGetDescr(parentRel),
8647 gettext_noop("could not convert row type"));
8648
8649 partFKs = copyObject(RelationGetFKeyList(partRel));
8650
8651 foreach(cell, clone)
8652 {
8653 Oid parentConstrOid = lfirst_oid(cell);
8654 Form_pg_constraint constrForm;
8655 Relation pkrel;
8656 HeapTuple tuple;
8657 int numfks;
8658 AttrNumber conkey[INDEX_MAX_KEYS];
8659 AttrNumber mapped_conkey[INDEX_MAX_KEYS];
8660 AttrNumber confkey[INDEX_MAX_KEYS];
8661 Oid conpfeqop[INDEX_MAX_KEYS];
8662 Oid conppeqop[INDEX_MAX_KEYS];
8663 Oid conffeqop[INDEX_MAX_KEYS];
8664 Constraint *fkconstraint;
8665 bool attached;
8666 Oid indexOid;
8667 Oid constrOid;
8668 ObjectAddress address,
8669 referenced;
8670 ListCell *cell;
8671
8672 tuple = SearchSysCache1(CONSTROID, parentConstrOid);
8673 if (!HeapTupleIsValid(tuple))
8674 elog(ERROR, "cache lookup failed for constraint %u",
8675 parentConstrOid);
8676 constrForm = (Form_pg_constraint) GETSTRUCT(tuple);
8677
8678 /* Don't clone constraints whose parents are being cloned */
8679 if (list_member_oid(clone, constrForm->conparentid))
8680 {
8681 ReleaseSysCache(tuple);
8682 continue;
8683 }
8684
8685 /*
8686 * Need to prevent concurrent deletions. If pkrel is a partitioned
8687 * relation, that means to lock all partitions.
8688 */
8689 pkrel = table_open(constrForm->confrelid, ShareRowExclusiveLock);
8690 if (pkrel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
8691 (void) find_all_inheritors(RelationGetRelid(pkrel),
8692 ShareRowExclusiveLock, NULL);
8693
8694 DeconstructFkConstraintRow(tuple, &numfks, conkey, confkey,
8695 conpfeqop, conppeqop, conffeqop);
8696 for (int i = 0; i < numfks; i++)
8697 mapped_conkey[i] = attmap[conkey[i] - 1];
8698
8699 /*
8700 * Before creating a new constraint, see whether any existing FKs are
8701 * fit for the purpose. If one is, attach the parent constraint to
8702 * it, and don't clone anything. This way we avoid the expensive
8703 * verification step and don't end up with a duplicate FK, and we
8704 * don't need to recurse to partitions for this constraint.
8705 */
8706 attached = false;
8707 foreach(cell, partFKs)
8708 {
8709 ForeignKeyCacheInfo *fk = lfirst_node(ForeignKeyCacheInfo, cell);
8710
8711 if (tryAttachPartitionForeignKey(fk,
8712 RelationGetRelid(partRel),
8713 parentConstrOid,
8714 numfks,
8715 mapped_conkey,
8716 confkey,
8717 conpfeqop))
8718 {
8719 attached = true;
8720 table_close(pkrel, NoLock);
8721 break;
8722 }
8723 }
8724 if (attached)
8725 {
8726 ReleaseSysCache(tuple);
8727 continue;
8728 }
8729
8730 /* No dice. Set up to create our own constraint */
8731 fkconstraint = makeNode(Constraint);
8732 if (ConstraintNameIsUsed(CONSTRAINT_RELATION,
8733 RelationGetRelid(partRel),
8734 NameStr(constrForm->conname)))
8735 fkconstraint->conname =
8736 ChooseConstraintName(RelationGetRelationName(partRel),
8737 ChooseForeignKeyConstraintNameAddition(fkconstraint->fk_attrs),
8738 "fkey",
8739 RelationGetNamespace(partRel), NIL);
8740 else
8741 fkconstraint->conname = pstrdup(NameStr(constrForm->conname));
8742 fkconstraint->fk_upd_action = constrForm->confupdtype;
8743 fkconstraint->fk_del_action = constrForm->confdeltype;
8744 fkconstraint->deferrable = constrForm->condeferrable;
8745 fkconstraint->initdeferred = constrForm->condeferred;
8746 fkconstraint->fk_matchtype = constrForm->confmatchtype;
8747 for (int i = 0; i < numfks; i++)
8748 {
8749 Form_pg_attribute att;
8750
8751 att = TupleDescAttr(RelationGetDescr(partRel),
8752 mapped_conkey[i] - 1);
8753 fkconstraint->fk_attrs = lappend(fkconstraint->fk_attrs,
8754 makeString(NameStr(att->attname)));
8755 }
8756
8757 indexOid = constrForm->conindid;
8758 constrOid =
8759 CreateConstraintEntry(fkconstraint->conname,
8760 constrForm->connamespace,
8761 CONSTRAINT_FOREIGN,
8762 fkconstraint->deferrable,
8763 fkconstraint->initdeferred,
8764 constrForm->convalidated,
8765 parentConstrOid,
8766 RelationGetRelid(partRel),
8767 mapped_conkey,
8768 numfks,
8769 numfks,
8770 InvalidOid, /* not a domain constraint */
8771 indexOid,
8772 constrForm->confrelid, /* same foreign rel */
8773 confkey,
8774 conpfeqop,
8775 conppeqop,
8776 conffeqop,
8777 numfks,
8778 fkconstraint->fk_upd_action,
8779 fkconstraint->fk_del_action,
8780 fkconstraint->fk_matchtype,
8781 NULL,
8782 NULL,
8783 NULL,
8784 false, /* islocal */
8785 1, /* inhcount */
8786 false, /* conNoInherit */
8787 true);
8788
8789 /* Set up partition dependencies for the new constraint */
8790 ObjectAddressSet(address, ConstraintRelationId, constrOid);
8791 ObjectAddressSet(referenced, ConstraintRelationId, parentConstrOid);
8792 recordDependencyOn(&address, &referenced, DEPENDENCY_PARTITION_PRI);
8793 ObjectAddressSet(referenced, RelationRelationId,
8794 RelationGetRelid(partRel));
8795 recordDependencyOn(&address, &referenced, DEPENDENCY_PARTITION_SEC);
8796
8797 /* Done with the cloned constraint's tuple */
8798 ReleaseSysCache(tuple);
8799
8800 /* Make all this visible before recursing */
8801 CommandCounterIncrement();
8802
8803 addFkRecurseReferencing(wqueue,
8804 fkconstraint,
8805 partRel,
8806 pkrel,
8807 indexOid,
8808 constrOid,
8809 numfks,
8810 confkey,
8811 mapped_conkey,
8812 conpfeqop,
8813 conppeqop,
8814 conffeqop,
8815 false, /* no old check exists */
8816 AccessExclusiveLock);
8817 table_close(pkrel, NoLock);
8818 }
8819}
8820
8821/*
8822 * When the parent of a partition receives [the referencing side of] a foreign
8823 * key, we must propagate that foreign key to the partition. However, the
8824 * partition might already have an equivalent foreign key; this routine
8825 * compares the given ForeignKeyCacheInfo (in the partition) to the FK defined
8826 * by the other parameters. If they are equivalent, create the link between
8827 * the two constraints and return true.
8828 *
8829 * If the given FK does not match the one defined by rest of the params,
8830 * return false.
8831 */
8832static bool
8833tryAttachPartitionForeignKey(ForeignKeyCacheInfo *fk,
8834 Oid partRelid,
8835 Oid parentConstrOid,
8836 int numfks,
8837 AttrNumber *mapped_conkey,
8838 AttrNumber *confkey,
8839 Oid *conpfeqop)
8840{
8841 HeapTuple parentConstrTup;
8842 Form_pg_constraint parentConstr;
8843 HeapTuple partcontup;
8844 Form_pg_constraint partConstr;
8845 Relation trigrel;
8846 ScanKeyData key;
8847 SysScanDesc scan;
8848 HeapTuple trigtup;
8849
8850 parentConstrTup = SearchSysCache1(CONSTROID,
8851 ObjectIdGetDatum(parentConstrOid));
8852 if (!HeapTupleIsValid(parentConstrTup))
8853 elog(ERROR, "cache lookup failed for constraint %u", parentConstrOid);
8854 parentConstr = (Form_pg_constraint) GETSTRUCT(parentConstrTup);
8855
8856 /*
8857 * Do some quick & easy initial checks. If any of these fail, we cannot
8858 * use this constraint.
8859 */
8860 if (fk->confrelid != parentConstr->confrelid || fk->nkeys != numfks)
8861 {
8862 ReleaseSysCache(parentConstrTup);
8863 return false;
8864 }
8865 for (int i = 0; i < numfks; i++)
8866 {
8867 if (fk->conkey[i] != mapped_conkey[i] ||
8868 fk->confkey[i] != confkey[i] ||
8869 fk->conpfeqop[i] != conpfeqop[i])
8870 {
8871 ReleaseSysCache(parentConstrTup);
8872 return false;
8873 }
8874 }
8875
8876 /*
8877 * Looks good so far; do some more extensive checks. Presumably the check
8878 * for 'convalidated' could be dropped, since we don't really care about
8879 * that, but let's be careful for now.
8880 */
8881 partcontup = SearchSysCache1(CONSTROID,
8882 ObjectIdGetDatum(fk->conoid));
8883 if (!HeapTupleIsValid(partcontup))
8884 elog(ERROR, "cache lookup failed for constraint %u", fk->conoid);
8885 partConstr = (Form_pg_constraint) GETSTRUCT(partcontup);
8886 if (OidIsValid(partConstr->conparentid) ||
8887 !partConstr->convalidated ||
8888 partConstr->condeferrable != parentConstr->condeferrable ||
8889 partConstr->condeferred != parentConstr->condeferred ||
8890 partConstr->confupdtype != parentConstr->confupdtype ||
8891 partConstr->confdeltype != parentConstr->confdeltype ||
8892 partConstr->confmatchtype != parentConstr->confmatchtype)
8893 {
8894 ReleaseSysCache(parentConstrTup);
8895 ReleaseSysCache(partcontup);
8896 return false;
8897 }
8898
8899 ReleaseSysCache(partcontup);
8900 ReleaseSysCache(parentConstrTup);
8901
8902 /*
8903 * Looks good! Attach this constraint. The action triggers in the new
8904 * partition become redundant -- the parent table already has equivalent
8905 * ones, and those will be able to reach the partition. Remove the ones
8906 * in the partition. We identify them because they have our constraint
8907 * OID, as well as being on the referenced rel.
8908 */
8909 trigrel = table_open(TriggerRelationId, RowExclusiveLock);
8910 ScanKeyInit(&key,
8911 Anum_pg_trigger_tgconstraint,
8912 BTEqualStrategyNumber, F_OIDEQ,
8913 ObjectIdGetDatum(fk->conoid));
8914
8915 scan = systable_beginscan(trigrel, TriggerConstraintIndexId, true,
8916 NULL, 1, &key);
8917 while ((trigtup = systable_getnext(scan)) != NULL)
8918 {
8919 Form_pg_trigger trgform = (Form_pg_trigger) GETSTRUCT(trigtup);
8920 ObjectAddress trigger;
8921
8922 if (trgform->tgconstrrelid != fk->conrelid)
8923 continue;
8924 if (trgform->tgrelid != fk->confrelid)
8925 continue;
8926
8927 /*
8928 * The constraint is originally set up to contain this trigger as an
8929 * implementation object, so there's a dependency record that links
8930 * the two; however, since the trigger is no longer needed, we remove
8931 * the dependency link in order to be able to drop the trigger while
8932 * keeping the constraint intact.
8933 */
8934 deleteDependencyRecordsFor(TriggerRelationId,
8935 trgform->oid,
8936 false);
8937 /* make dependency deletion visible to performDeletion */
8938 CommandCounterIncrement();
8939 ObjectAddressSet(trigger, TriggerRelationId,
8940 trgform->oid);
8941 performDeletion(&trigger, DROP_RESTRICT, 0);
8942 /* make trigger drop visible, in case the loop iterates */
8943 CommandCounterIncrement();
8944 }
8945
8946 systable_endscan(scan);
8947 table_close(trigrel, RowExclusiveLock);
8948
8949 ConstraintSetParentConstraint(fk->conoid, parentConstrOid, partRelid);
8950 CommandCounterIncrement();
8951 return true;
8952}
8953
8954
8955/*
8956 * ALTER TABLE ALTER CONSTRAINT
8957 *
8958 * Update the attributes of a constraint.
8959 *
8960 * Currently only works for Foreign Key constraints.
8961 * Foreign keys do not inherit, so we purposely ignore the
8962 * recursion bit here, but we keep the API the same for when
8963 * other constraint types are supported.
8964 *
8965 * If the constraint is modified, returns its address; otherwise, return
8966 * InvalidObjectAddress.
8967 */
8968static ObjectAddress
8969ATExecAlterConstraint(Relation rel, AlterTableCmd *cmd,
8970 bool recurse, bool recursing, LOCKMODE lockmode)
8971{
8972 Constraint *cmdcon;
8973 Relation conrel;
8974 SysScanDesc scan;
8975 ScanKeyData skey[3];
8976 HeapTuple contuple;
8977 Form_pg_constraint currcon;
8978 ObjectAddress address;
8979
8980 cmdcon = castNode(Constraint, cmd->def);
8981
8982 conrel = table_open(ConstraintRelationId, RowExclusiveLock);
8983
8984 /*
8985 * Find and check the target constraint
8986 */
8987 ScanKeyInit(&skey[0],
8988 Anum_pg_constraint_conrelid,
8989 BTEqualStrategyNumber, F_OIDEQ,
8990 ObjectIdGetDatum(RelationGetRelid(rel)));
8991 ScanKeyInit(&skey[1],
8992 Anum_pg_constraint_contypid,
8993 BTEqualStrategyNumber, F_OIDEQ,
8994 ObjectIdGetDatum(InvalidOid));
8995 ScanKeyInit(&skey[2],
8996 Anum_pg_constraint_conname,
8997 BTEqualStrategyNumber, F_NAMEEQ,
8998 CStringGetDatum(cmdcon->conname));
8999 scan = systable_beginscan(conrel, ConstraintRelidTypidNameIndexId,
9000 true, NULL, 3, skey);
9001
9002 /* There can be at most one matching row */
9003 if (!HeapTupleIsValid(contuple = systable_getnext(scan)))
9004 ereport(ERROR,
9005 (errcode(ERRCODE_UNDEFINED_OBJECT),
9006 errmsg("constraint \"%s\" of relation \"%s\" does not exist",
9007 cmdcon->conname, RelationGetRelationName(rel))));
9008
9009 currcon = (Form_pg_constraint) GETSTRUCT(contuple);
9010 if (currcon->contype != CONSTRAINT_FOREIGN)
9011 ereport(ERROR,
9012 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
9013 errmsg("constraint \"%s\" of relation \"%s\" is not a foreign key constraint",
9014 cmdcon->conname, RelationGetRelationName(rel))));
9015
9016 if (currcon->condeferrable != cmdcon->deferrable ||
9017 currcon->condeferred != cmdcon->initdeferred)
9018 {
9019 HeapTuple copyTuple;
9020 HeapTuple tgtuple;
9021 Form_pg_constraint copy_con;
9022 List *otherrelids = NIL;
9023 ScanKeyData tgkey;
9024 SysScanDesc tgscan;
9025 Relation tgrel;
9026 ListCell *lc;
9027
9028 /*
9029 * Now update the catalog, while we have the door open.
9030 */
9031 copyTuple = heap_copytuple(contuple);
9032 copy_con = (Form_pg_constraint) GETSTRUCT(copyTuple);
9033 copy_con->condeferrable = cmdcon->deferrable;
9034 copy_con->condeferred = cmdcon->initdeferred;
9035 CatalogTupleUpdate(conrel, &copyTuple->t_self, copyTuple);
9036
9037 InvokeObjectPostAlterHook(ConstraintRelationId,
9038 currcon->oid, 0);
9039
9040 heap_freetuple(copyTuple);
9041
9042 /*
9043 * Now we need to update the multiple entries in pg_trigger that
9044 * implement the constraint.
9045 */
9046 tgrel = table_open(TriggerRelationId, RowExclusiveLock);
9047
9048 ScanKeyInit(&tgkey,
9049 Anum_pg_trigger_tgconstraint,
9050 BTEqualStrategyNumber, F_OIDEQ,
9051 ObjectIdGetDatum(currcon->oid));
9052
9053 tgscan = systable_beginscan(tgrel, TriggerConstraintIndexId, true,
9054 NULL, 1, &tgkey);
9055
9056 while (HeapTupleIsValid(tgtuple = systable_getnext(tgscan)))
9057 {
9058 Form_pg_trigger tgform = (Form_pg_trigger) GETSTRUCT(tgtuple);
9059 Form_pg_trigger copy_tg;
9060
9061 /*
9062 * Remember OIDs of other relation(s) involved in FK constraint.
9063 * (Note: it's likely that we could skip forcing a relcache inval
9064 * for other rels that don't have a trigger whose properties
9065 * change, but let's be conservative.)
9066 */
9067 if (tgform->tgrelid != RelationGetRelid(rel))
9068 otherrelids = list_append_unique_oid(otherrelids,
9069 tgform->tgrelid);
9070
9071 /*
9072 * Update deferrability of RI_FKey_noaction_del,
9073 * RI_FKey_noaction_upd, RI_FKey_check_ins and RI_FKey_check_upd
9074 * triggers, but not others; see createForeignKeyActionTriggers
9075 * and CreateFKCheckTrigger.
9076 */
9077 if (tgform->tgfoid != F_RI_FKEY_NOACTION_DEL &&
9078 tgform->tgfoid != F_RI_FKEY_NOACTION_UPD &&
9079 tgform->tgfoid != F_RI_FKEY_CHECK_INS &&
9080 tgform->tgfoid != F_RI_FKEY_CHECK_UPD)
9081 continue;
9082
9083 copyTuple = heap_copytuple(tgtuple);
9084 copy_tg = (Form_pg_trigger) GETSTRUCT(copyTuple);
9085
9086 copy_tg->tgdeferrable = cmdcon->deferrable;
9087 copy_tg->tginitdeferred = cmdcon->initdeferred;
9088 CatalogTupleUpdate(tgrel, &copyTuple->t_self, copyTuple);
9089
9090 InvokeObjectPostAlterHook(TriggerRelationId, currcon->oid, 0);
9091
9092 heap_freetuple(copyTuple);
9093 }
9094
9095 systable_endscan(tgscan);
9096
9097 table_close(tgrel, RowExclusiveLock);
9098
9099 /*
9100 * Invalidate relcache so that others see the new attributes. We must
9101 * inval both the named rel and any others having relevant triggers.
9102 * (At present there should always be exactly one other rel, but
9103 * there's no need to hard-wire such an assumption here.)
9104 */
9105 CacheInvalidateRelcache(rel);
9106 foreach(lc, otherrelids)
9107 {
9108 CacheInvalidateRelcacheByRelid(lfirst_oid(lc));
9109 }
9110
9111 ObjectAddressSet(address, ConstraintRelationId, currcon->oid);
9112 }
9113 else
9114 address = InvalidObjectAddress;
9115
9116 systable_endscan(scan);
9117
9118 table_close(conrel, RowExclusiveLock);
9119
9120 return address;
9121}
9122
9123/*
9124 * ALTER TABLE VALIDATE CONSTRAINT
9125 *
9126 * XXX The reason we handle recursion here rather than at Phase 1 is because
9127 * there's no good way to skip recursing when handling foreign keys: there is
9128 * no need to lock children in that case, yet we wouldn't be able to avoid
9129 * doing so at that level.
9130 *
9131 * Return value is the address of the validated constraint. If the constraint
9132 * was already validated, InvalidObjectAddress is returned.
9133 */
9134static ObjectAddress
9135ATExecValidateConstraint(Relation rel, char *constrName, bool recurse,
9136 bool recursing, LOCKMODE lockmode)
9137{
9138 Relation conrel;
9139 SysScanDesc scan;
9140 ScanKeyData skey[3];
9141 HeapTuple tuple;
9142 Form_pg_constraint con;
9143 ObjectAddress address;
9144
9145 conrel = table_open(ConstraintRelationId, RowExclusiveLock);
9146
9147 /*
9148 * Find and check the target constraint
9149 */
9150 ScanKeyInit(&skey[0],
9151 Anum_pg_constraint_conrelid,
9152 BTEqualStrategyNumber, F_OIDEQ,
9153 ObjectIdGetDatum(RelationGetRelid(rel)));
9154 ScanKeyInit(&skey[1],
9155 Anum_pg_constraint_contypid,
9156 BTEqualStrategyNumber, F_OIDEQ,
9157 ObjectIdGetDatum(InvalidOid));
9158 ScanKeyInit(&skey[2],
9159 Anum_pg_constraint_conname,
9160 BTEqualStrategyNumber, F_NAMEEQ,
9161 CStringGetDatum(constrName));
9162 scan = systable_beginscan(conrel, ConstraintRelidTypidNameIndexId,
9163 true, NULL, 3, skey);
9164
9165 /* There can be at most one matching row */
9166 if (!HeapTupleIsValid(tuple = systable_getnext(scan)))
9167 ereport(ERROR,
9168 (errcode(ERRCODE_UNDEFINED_OBJECT),
9169 errmsg("constraint \"%s\" of relation \"%s\" does not exist",
9170 constrName, RelationGetRelationName(rel))));
9171
9172 con = (Form_pg_constraint) GETSTRUCT(tuple);
9173 if (con->contype != CONSTRAINT_FOREIGN &&
9174 con->contype != CONSTRAINT_CHECK)
9175 ereport(ERROR,
9176 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
9177 errmsg("constraint \"%s\" of relation \"%s\" is not a foreign key or check constraint",
9178 constrName, RelationGetRelationName(rel))));
9179
9180 if (!con->convalidated)
9181 {
9182 HeapTuple copyTuple;
9183 Form_pg_constraint copy_con;
9184
9185 if (con->contype == CONSTRAINT_FOREIGN)
9186 {
9187 Relation refrel;
9188
9189 /*
9190 * Triggers are already in place on both tables, so a concurrent
9191 * write that alters the result here is not possible. Normally we
9192 * can run a query here to do the validation, which would only
9193 * require AccessShareLock. In some cases, it is possible that we
9194 * might need to fire triggers to perform the check, so we take a
9195 * lock at RowShareLock level just in case.
9196 */
9197 refrel = table_open(con->confrelid, RowShareLock);
9198
9199 validateForeignKeyConstraint(constrName, rel, refrel,
9200 con->conindid,
9201 con->oid);
9202 table_close(refrel, NoLock);
9203
9204 /*
9205 * We disallow creating invalid foreign keys to or from
9206 * partitioned tables, so ignoring the recursion bit is okay.
9207 */
9208 }
9209 else if (con->contype == CONSTRAINT_CHECK)
9210 {
9211 List *children = NIL;
9212 ListCell *child;
9213
9214 /*
9215 * If we're recursing, the parent has already done this, so skip
9216 * it. Also, if the constraint is a NO INHERIT constraint, we
9217 * shouldn't try to look for it in the children.
9218 */
9219 if (!recursing && !con->connoinherit)
9220 children = find_all_inheritors(RelationGetRelid(rel),
9221 lockmode, NULL);
9222
9223 /*
9224 * For CHECK constraints, we must ensure that we only mark the
9225 * constraint as validated on the parent if it's already validated
9226 * on the children.
9227 *
9228 * We recurse before validating on the parent, to reduce risk of
9229 * deadlocks.
9230 */
9231 foreach(child, children)
9232 {
9233 Oid childoid = lfirst_oid(child);
9234 Relation childrel;
9235
9236 if (childoid == RelationGetRelid(rel))
9237 continue;
9238
9239 /*
9240 * If we are told not to recurse, there had better not be any
9241 * child tables, because we can't mark the constraint on the
9242 * parent valid unless it is valid for all child tables.
9243 */
9244 if (!recurse)
9245 ereport(ERROR,
9246 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
9247 errmsg("constraint must be validated on child tables too")));
9248
9249 /* find_all_inheritors already got lock */
9250 childrel = table_open(childoid, NoLock);
9251
9252 ATExecValidateConstraint(childrel, constrName, false,
9253 true, lockmode);
9254 table_close(childrel, NoLock);
9255 }
9256
9257 validateCheckConstraint(rel, tuple);
9258
9259 /*
9260 * Invalidate relcache so that others see the new validated
9261 * constraint.
9262 */
9263 CacheInvalidateRelcache(rel);
9264 }
9265
9266 /*
9267 * Now update the catalog, while we have the door open.
9268 */
9269 copyTuple = heap_copytuple(tuple);
9270 copy_con = (Form_pg_constraint) GETSTRUCT(copyTuple);
9271 copy_con->convalidated = true;
9272 CatalogTupleUpdate(conrel, &copyTuple->t_self, copyTuple);
9273
9274 InvokeObjectPostAlterHook(ConstraintRelationId, con->oid, 0);
9275
9276 heap_freetuple(copyTuple);
9277
9278 ObjectAddressSet(address, ConstraintRelationId, con->oid);
9279 }
9280 else
9281 address = InvalidObjectAddress; /* already validated */
9282
9283 systable_endscan(scan);
9284
9285 table_close(conrel, RowExclusiveLock);
9286
9287 return address;
9288}
9289
9290
9291/*
9292 * transformColumnNameList - transform list of column names
9293 *
9294 * Lookup each name and return its attnum and type OID
9295 */
9296static int
9297transformColumnNameList(Oid relId, List *colList,
9298 int16 *attnums, Oid *atttypids)
9299{
9300 ListCell *l;
9301 int attnum;
9302
9303 attnum = 0;
9304 foreach(l, colList)
9305 {
9306 char *attname = strVal(lfirst(l));
9307 HeapTuple atttuple;
9308
9309 atttuple = SearchSysCacheAttName(relId, attname);
9310 if (!HeapTupleIsValid(atttuple))
9311 ereport(ERROR,
9312 (errcode(ERRCODE_UNDEFINED_COLUMN),
9313 errmsg("column \"%s\" referenced in foreign key constraint does not exist",
9314 attname)));
9315 if (attnum >= INDEX_MAX_KEYS)
9316 ereport(ERROR,
9317 (errcode(ERRCODE_TOO_MANY_COLUMNS),
9318 errmsg("cannot have more than %d keys in a foreign key",
9319 INDEX_MAX_KEYS)));
9320 attnums[attnum] = ((Form_pg_attribute) GETSTRUCT(atttuple))->attnum;
9321 atttypids[attnum] = ((Form_pg_attribute) GETSTRUCT(atttuple))->atttypid;
9322 ReleaseSysCache(atttuple);
9323 attnum++;
9324 }
9325
9326 return attnum;
9327}
9328
9329/*
9330 * transformFkeyGetPrimaryKey -
9331 *
9332 * Look up the names, attnums, and types of the primary key attributes
9333 * for the pkrel. Also return the index OID and index opclasses of the
9334 * index supporting the primary key.
9335 *
9336 * All parameters except pkrel are output parameters. Also, the function
9337 * return value is the number of attributes in the primary key.
9338 *
9339 * Used when the column list in the REFERENCES specification is omitted.
9340 */
9341static int
9342transformFkeyGetPrimaryKey(Relation pkrel, Oid *indexOid,
9343 List **attnamelist,
9344 int16 *attnums, Oid *atttypids,
9345 Oid *opclasses)
9346{
9347 List *indexoidlist;
9348 ListCell *indexoidscan;
9349 HeapTuple indexTuple = NULL;
9350 Form_pg_index indexStruct = NULL;
9351 Datum indclassDatum;
9352 bool isnull;
9353 oidvector *indclass;
9354 int i;
9355
9356 /*
9357 * Get the list of index OIDs for the table from the relcache, and look up
9358 * each one in the pg_index syscache until we find one marked primary key
9359 * (hopefully there isn't more than one such). Insist it's valid, too.
9360 */
9361 *indexOid = InvalidOid;
9362
9363 indexoidlist = RelationGetIndexList(pkrel);
9364
9365 foreach(indexoidscan, indexoidlist)
9366 {
9367 Oid indexoid = lfirst_oid(indexoidscan);
9368
9369 indexTuple = SearchSysCache1(INDEXRELID, ObjectIdGetDatum(indexoid));
9370 if (!HeapTupleIsValid(indexTuple))
9371 elog(ERROR, "cache lookup failed for index %u", indexoid);
9372 indexStruct = (Form_pg_index) GETSTRUCT(indexTuple);
9373 if (indexStruct->indisprimary && indexStruct->indisvalid)
9374 {
9375 /*
9376 * Refuse to use a deferrable primary key. This is per SQL spec,
9377 * and there would be a lot of interesting semantic problems if we
9378 * tried to allow it.
9379 */
9380 if (!indexStruct->indimmediate)
9381 ereport(ERROR,
9382 (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
9383 errmsg("cannot use a deferrable primary key for referenced table \"%s\"",
9384 RelationGetRelationName(pkrel))));
9385
9386 *indexOid = indexoid;
9387 break;
9388 }
9389 ReleaseSysCache(indexTuple);
9390 }
9391
9392 list_free(indexoidlist);
9393
9394 /*
9395 * Check that we found it
9396 */
9397 if (!OidIsValid(*indexOid))
9398 ereport(ERROR,
9399 (errcode(ERRCODE_UNDEFINED_OBJECT),
9400 errmsg("there is no primary key for referenced table \"%s\"",
9401 RelationGetRelationName(pkrel))));
9402
9403 /* Must get indclass the hard way */
9404 indclassDatum = SysCacheGetAttr(INDEXRELID, indexTuple,
9405 Anum_pg_index_indclass, &isnull);
9406 Assert(!isnull);
9407 indclass = (oidvector *) DatumGetPointer(indclassDatum);
9408
9409 /*
9410 * Now build the list of PK attributes from the indkey definition (we
9411 * assume a primary key cannot have expressional elements)
9412 */
9413 *attnamelist = NIL;
9414 for (i = 0; i < indexStruct->indnkeyatts; i++)
9415 {
9416 int pkattno = indexStruct->indkey.values[i];
9417
9418 attnums[i] = pkattno;
9419 atttypids[i] = attnumTypeId(pkrel, pkattno);
9420 opclasses[i] = indclass->values[i];
9421 *attnamelist = lappend(*attnamelist,
9422 makeString(pstrdup(NameStr(*attnumAttName(pkrel, pkattno)))));
9423 }
9424
9425 ReleaseSysCache(indexTuple);
9426
9427 return i;
9428}
9429
9430/*
9431 * transformFkeyCheckAttrs -
9432 *
9433 * Make sure that the attributes of a referenced table belong to a unique
9434 * (or primary key) constraint. Return the OID of the index supporting
9435 * the constraint, as well as the opclasses associated with the index
9436 * columns.
9437 */
9438static Oid
9439transformFkeyCheckAttrs(Relation pkrel,
9440 int numattrs, int16 *attnums,
9441 Oid *opclasses) /* output parameter */
9442{
9443 Oid indexoid = InvalidOid;
9444 bool found = false;
9445 bool found_deferrable = false;
9446 List *indexoidlist;
9447 ListCell *indexoidscan;
9448 int i,
9449 j;
9450
9451 /*
9452 * Reject duplicate appearances of columns in the referenced-columns list.
9453 * Such a case is forbidden by the SQL standard, and even if we thought it
9454 * useful to allow it, there would be ambiguity about how to match the
9455 * list to unique indexes (in particular, it'd be unclear which index
9456 * opclass goes with which FK column).
9457 */
9458 for (i = 0; i < numattrs; i++)
9459 {
9460 for (j = i + 1; j < numattrs; j++)
9461 {
9462 if (attnums[i] == attnums[j])
9463 ereport(ERROR,
9464 (errcode(ERRCODE_INVALID_FOREIGN_KEY),
9465 errmsg("foreign key referenced-columns list must not contain duplicates")));
9466 }
9467 }
9468
9469 /*
9470 * Get the list of index OIDs for the table from the relcache, and look up
9471 * each one in the pg_index syscache, and match unique indexes to the list
9472 * of attnums we are given.
9473 */
9474 indexoidlist = RelationGetIndexList(pkrel);
9475
9476 foreach(indexoidscan, indexoidlist)
9477 {
9478 HeapTuple indexTuple;
9479 Form_pg_index indexStruct;
9480
9481 indexoid = lfirst_oid(indexoidscan);
9482 indexTuple = SearchSysCache1(INDEXRELID, ObjectIdGetDatum(indexoid));
9483 if (!HeapTupleIsValid(indexTuple))
9484 elog(ERROR, "cache lookup failed for index %u", indexoid);
9485 indexStruct = (Form_pg_index) GETSTRUCT(indexTuple);
9486
9487 /*
9488 * Must have the right number of columns; must be unique and not a
9489 * partial index; forget it if there are any expressions, too. Invalid
9490 * indexes are out as well.
9491 */
9492 if (indexStruct->indnkeyatts == numattrs &&
9493 indexStruct->indisunique &&
9494 indexStruct->indisvalid &&
9495 heap_attisnull(indexTuple, Anum_pg_index_indpred, NULL) &&
9496 heap_attisnull(indexTuple, Anum_pg_index_indexprs, NULL))
9497 {
9498 Datum indclassDatum;
9499 bool isnull;
9500 oidvector *indclass;
9501
9502 /* Must get indclass the hard way */
9503 indclassDatum = SysCacheGetAttr(INDEXRELID, indexTuple,
9504 Anum_pg_index_indclass, &isnull);
9505 Assert(!isnull);
9506 indclass = (oidvector *) DatumGetPointer(indclassDatum);
9507
9508 /*
9509 * The given attnum list may match the index columns in any order.
9510 * Check for a match, and extract the appropriate opclasses while
9511 * we're at it.
9512 *
9513 * We know that attnums[] is duplicate-free per the test at the
9514 * start of this function, and we checked above that the number of
9515 * index columns agrees, so if we find a match for each attnums[]
9516 * entry then we must have a one-to-one match in some order.
9517 */
9518 for (i = 0; i < numattrs; i++)
9519 {
9520 found = false;
9521 for (j = 0; j < numattrs; j++)
9522 {
9523 if (attnums[i] == indexStruct->indkey.values[j])
9524 {
9525 opclasses[i] = indclass->values[j];
9526 found = true;
9527 break;
9528 }
9529 }
9530 if (!found)
9531 break;
9532 }
9533
9534 /*
9535 * Refuse to use a deferrable unique/primary key. This is per SQL
9536 * spec, and there would be a lot of interesting semantic problems
9537 * if we tried to allow it.
9538 */
9539 if (found && !indexStruct->indimmediate)
9540 {
9541 /*
9542 * Remember that we found an otherwise matching index, so that
9543 * we can generate a more appropriate error message.
9544 */
9545 found_deferrable = true;
9546 found = false;
9547 }
9548 }
9549 ReleaseSysCache(indexTuple);
9550 if (found)
9551 break;
9552 }
9553
9554 if (!found)
9555 {
9556 if (found_deferrable)
9557 ereport(ERROR,
9558 (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
9559 errmsg("cannot use a deferrable unique constraint for referenced table \"%s\"",
9560 RelationGetRelationName(pkrel))));
9561 else
9562 ereport(ERROR,
9563 (errcode(ERRCODE_INVALID_FOREIGN_KEY),
9564 errmsg("there is no unique constraint matching given keys for referenced table \"%s\"",
9565 RelationGetRelationName(pkrel))));
9566 }
9567
9568 list_free(indexoidlist);
9569
9570 return indexoid;
9571}
9572
9573/*
9574 * findFkeyCast -
9575 *
9576 * Wrapper around find_coercion_pathway() for ATAddForeignKeyConstraint().
9577 * Caller has equal regard for binary coercibility and for an exact match.
9578*/
9579static CoercionPathType
9580findFkeyCast(Oid targetTypeId, Oid sourceTypeId, Oid *funcid)
9581{
9582 CoercionPathType ret;
9583
9584 if (targetTypeId == sourceTypeId)
9585 {
9586 ret = COERCION_PATH_RELABELTYPE;
9587 *funcid = InvalidOid;
9588 }
9589 else
9590 {
9591 ret = find_coercion_pathway(targetTypeId, sourceTypeId,
9592 COERCION_IMPLICIT, funcid);
9593 if (ret == COERCION_PATH_NONE)
9594 /* A previously-relied-upon cast is now gone. */
9595 elog(ERROR, "could not find cast from %u to %u",
9596 sourceTypeId, targetTypeId);
9597 }
9598
9599 return ret;
9600}
9601
9602/*
9603 * Permissions checks on the referenced table for ADD FOREIGN KEY
9604 *
9605 * Note: we have already checked that the user owns the referencing table,
9606 * else we'd have failed much earlier; no additional checks are needed for it.
9607 */
9608static void
9609checkFkeyPermissions(Relation rel, int16 *attnums, int natts)
9610{
9611 Oid roleid = GetUserId();
9612 AclResult aclresult;
9613 int i;
9614
9615 /* Okay if we have relation-level REFERENCES permission */
9616 aclresult = pg_class_aclcheck(RelationGetRelid(rel), roleid,
9617 ACL_REFERENCES);
9618 if (aclresult == ACLCHECK_OK)
9619 return;
9620 /* Else we must have REFERENCES on each column */
9621 for (i = 0; i < natts; i++)
9622 {
9623 aclresult = pg_attribute_aclcheck(RelationGetRelid(rel), attnums[i],
9624 roleid, ACL_REFERENCES);
9625 if (aclresult != ACLCHECK_OK)
9626 aclcheck_error(aclresult, get_relkind_objtype(rel->rd_rel->relkind),
9627 RelationGetRelationName(rel));
9628 }
9629}
9630
9631/*
9632 * Scan the existing rows in a table to verify they meet a proposed
9633 * CHECK constraint.
9634 *
9635 * The caller must have opened and locked the relation appropriately.
9636 */
9637static void
9638validateCheckConstraint(Relation rel, HeapTuple constrtup)
9639{
9640 EState *estate;
9641 Datum val;
9642 char *conbin;
9643 Expr *origexpr;
9644 ExprState *exprstate;
9645 TableScanDesc scan;
9646 ExprContext *econtext;
9647 MemoryContext oldcxt;
9648 TupleTableSlot *slot;
9649 Form_pg_constraint constrForm;
9650 bool isnull;
9651 Snapshot snapshot;
9652
9653 /*
9654 * VALIDATE CONSTRAINT is a no-op for foreign tables and partitioned
9655 * tables.
9656 */
9657 if (rel->rd_rel->relkind == RELKIND_FOREIGN_TABLE ||
9658 rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
9659 return;
9660
9661 constrForm = (Form_pg_constraint) GETSTRUCT(constrtup);
9662
9663 estate = CreateExecutorState();
9664
9665 /*
9666 * XXX this tuple doesn't really come from a syscache, but this doesn't
9667 * matter to SysCacheGetAttr, because it only wants to be able to fetch
9668 * the tupdesc
9669 */
9670 val = SysCacheGetAttr(CONSTROID, constrtup, Anum_pg_constraint_conbin,
9671 &isnull);
9672 if (isnull)
9673 elog(ERROR, "null conbin for constraint %u",
9674 constrForm->oid);
9675 conbin = TextDatumGetCString(val);
9676 origexpr = (Expr *) stringToNode(conbin);
9677 exprstate = ExecPrepareExpr(origexpr, estate);
9678
9679 econtext = GetPerTupleExprContext(estate);
9680 slot = table_slot_create(rel, NULL);
9681 econtext->ecxt_scantuple = slot;
9682
9683 snapshot = RegisterSnapshot(GetLatestSnapshot());
9684 scan = table_beginscan(rel, snapshot, 0, NULL);
9685
9686 /*
9687 * Switch to per-tuple memory context and reset it for each tuple
9688 * produced, so we don't leak memory.
9689 */
9690 oldcxt = MemoryContextSwitchTo(GetPerTupleMemoryContext(estate));
9691
9692 while (table_scan_getnextslot(scan, ForwardScanDirection, slot))
9693 {
9694 if (!ExecCheck(exprstate, econtext))
9695 ereport(ERROR,
9696 (errcode(ERRCODE_CHECK_VIOLATION),
9697 errmsg("check constraint \"%s\" is violated by some row",
9698 NameStr(constrForm->conname)),
9699 errtableconstraint(rel, NameStr(constrForm->conname))));
9700
9701 ResetExprContext(econtext);
9702 }
9703
9704 MemoryContextSwitchTo(oldcxt);
9705 table_endscan(scan);
9706 UnregisterSnapshot(snapshot);
9707 ExecDropSingleTupleTableSlot(slot);
9708 FreeExecutorState(estate);
9709}
9710
9711/*
9712 * Scan the existing rows in a table to verify they meet a proposed FK
9713 * constraint.
9714 *
9715 * Caller must have opened and locked both relations appropriately.
9716 */
9717static void
9718validateForeignKeyConstraint(char *conname,
9719 Relation rel,
9720 Relation pkrel,
9721 Oid pkindOid,
9722 Oid constraintOid)
9723{
9724 TupleTableSlot *slot;
9725 TableScanDesc scan;
9726 Trigger trig;
9727 Snapshot snapshot;
9728 MemoryContext oldcxt;
9729 MemoryContext perTupCxt;
9730
9731 ereport(DEBUG1,
9732 (errmsg("validating foreign key constraint \"%s\"", conname)));
9733
9734 /*
9735 * Build a trigger call structure; we'll need it either way.
9736 */
9737 MemSet(&trig, 0, sizeof(trig));
9738 trig.tgoid = InvalidOid;
9739 trig.tgname = conname;
9740 trig.tgenabled = TRIGGER_FIRES_ON_ORIGIN;
9741 trig.tgisinternal = true;
9742 trig.tgconstrrelid = RelationGetRelid(pkrel);
9743 trig.tgconstrindid = pkindOid;
9744 trig.tgconstraint = constraintOid;
9745 trig.tgdeferrable = false;
9746 trig.tginitdeferred = false;
9747 /* we needn't fill in remaining fields */
9748
9749 /*
9750 * See if we can do it with a single LEFT JOIN query. A false result
9751 * indicates we must proceed with the fire-the-trigger method.
9752 */
9753 if (RI_Initial_Check(&trig, rel, pkrel))
9754 return;
9755
9756 /*
9757 * Scan through each tuple, calling RI_FKey_check_ins (insert trigger) as
9758 * if that tuple had just been inserted. If any of those fail, it should
9759 * ereport(ERROR) and that's that.
9760 */
9761 snapshot = RegisterSnapshot(GetLatestSnapshot());
9762 slot = table_slot_create(rel, NULL);
9763 scan = table_beginscan(rel, snapshot, 0, NULL);
9764
9765 perTupCxt = AllocSetContextCreate(CurrentMemoryContext,
9766 "validateForeignKeyConstraint",
9767 ALLOCSET_SMALL_SIZES);
9768 oldcxt = MemoryContextSwitchTo(perTupCxt);
9769
9770 while (table_scan_getnextslot(scan, ForwardScanDirection, slot))
9771 {
9772 LOCAL_FCINFO(fcinfo, 0);
9773 TriggerData trigdata;
9774
9775 CHECK_FOR_INTERRUPTS();
9776
9777 /*
9778 * Make a call to the trigger function
9779 *
9780 * No parameters are passed, but we do set a context
9781 */
9782 MemSet(fcinfo, 0, SizeForFunctionCallInfo(0));
9783
9784 /*
9785 * We assume RI_FKey_check_ins won't look at flinfo...
9786 */
9787 trigdata.type = T_TriggerData;
9788 trigdata.tg_event = TRIGGER_EVENT_INSERT | TRIGGER_EVENT_ROW;
9789 trigdata.tg_relation = rel;
9790 trigdata.tg_trigtuple = ExecFetchSlotHeapTuple(slot, false, NULL);
9791 trigdata.tg_trigslot = slot;
9792 trigdata.tg_newtuple = NULL;
9793 trigdata.tg_newslot = NULL;
9794 trigdata.tg_trigger = &trig;
9795
9796 fcinfo->context = (Node *) &trigdata;
9797
9798 RI_FKey_check_ins(fcinfo);
9799
9800 MemoryContextReset(perTupCxt);
9801 }
9802
9803 MemoryContextSwitchTo(oldcxt);
9804 MemoryContextDelete(perTupCxt);
9805 table_endscan(scan);
9806 UnregisterSnapshot(snapshot);
9807 ExecDropSingleTupleTableSlot(slot);
9808}
9809
9810static void
9811CreateFKCheckTrigger(Oid myRelOid, Oid refRelOid, Constraint *fkconstraint,
9812 Oid constraintOid, Oid indexOid, bool on_insert)
9813{
9814 CreateTrigStmt *fk_trigger;
9815
9816 /*
9817 * Note: for a self-referential FK (referencing and referenced tables are
9818 * the same), it is important that the ON UPDATE action fires before the
9819 * CHECK action, since both triggers will fire on the same row during an
9820 * UPDATE event; otherwise the CHECK trigger will be checking a non-final
9821 * state of the row. Triggers fire in name order, so we ensure this by
9822 * using names like "RI_ConstraintTrigger_a_NNNN" for the action triggers
9823 * and "RI_ConstraintTrigger_c_NNNN" for the check triggers.
9824 */
9825 fk_trigger = makeNode(CreateTrigStmt);
9826 fk_trigger->trigname = "RI_ConstraintTrigger_c";
9827 fk_trigger->relation = NULL;
9828 fk_trigger->row = true;
9829 fk_trigger->timing = TRIGGER_TYPE_AFTER;
9830
9831 /* Either ON INSERT or ON UPDATE */
9832 if (on_insert)
9833 {
9834 fk_trigger->funcname = SystemFuncName("RI_FKey_check_ins");
9835 fk_trigger->events = TRIGGER_TYPE_INSERT;
9836 }
9837 else
9838 {
9839 fk_trigger->funcname = SystemFuncName("RI_FKey_check_upd");
9840 fk_trigger->events = TRIGGER_TYPE_UPDATE;
9841 }
9842
9843 fk_trigger->columns = NIL;
9844 fk_trigger->transitionRels = NIL;
9845 fk_trigger->whenClause = NULL;
9846 fk_trigger->isconstraint = true;
9847 fk_trigger->deferrable = fkconstraint->deferrable;
9848 fk_trigger->initdeferred = fkconstraint->initdeferred;
9849 fk_trigger->constrrel = NULL;
9850 fk_trigger->args = NIL;
9851
9852 (void) CreateTrigger(fk_trigger, NULL, myRelOid, refRelOid, constraintOid,
9853 indexOid, InvalidOid, InvalidOid, NULL, true, false);
9854
9855 /* Make changes-so-far visible */
9856 CommandCounterIncrement();
9857}
9858
9859/*
9860 * createForeignKeyActionTriggers
9861 * Create the referenced-side "action" triggers that implement a foreign
9862 * key.
9863 */
9864static void
9865createForeignKeyActionTriggers(Relation rel, Oid refRelOid, Constraint *fkconstraint,
9866 Oid constraintOid, Oid indexOid)
9867{
9868 CreateTrigStmt *fk_trigger;
9869
9870 /*
9871 * Build and execute a CREATE CONSTRAINT TRIGGER statement for the ON
9872 * DELETE action on the referenced table.
9873 */
9874 fk_trigger = makeNode(CreateTrigStmt);
9875 fk_trigger->trigname = "RI_ConstraintTrigger_a";
9876 fk_trigger->relation = NULL;
9877 fk_trigger->row = true;
9878 fk_trigger->timing = TRIGGER_TYPE_AFTER;
9879 fk_trigger->events = TRIGGER_TYPE_DELETE;
9880 fk_trigger->columns = NIL;
9881 fk_trigger->transitionRels = NIL;
9882 fk_trigger->whenClause = NULL;
9883 fk_trigger->isconstraint = true;
9884 fk_trigger->constrrel = NULL;
9885 switch (fkconstraint->fk_del_action)
9886 {
9887 case FKCONSTR_ACTION_NOACTION:
9888 fk_trigger->deferrable = fkconstraint->deferrable;
9889 fk_trigger->initdeferred = fkconstraint->initdeferred;
9890 fk_trigger->funcname = SystemFuncName("RI_FKey_noaction_del");
9891 break;
9892 case FKCONSTR_ACTION_RESTRICT:
9893 fk_trigger->deferrable = false;
9894 fk_trigger->initdeferred = false;
9895 fk_trigger->funcname = SystemFuncName("RI_FKey_restrict_del");
9896 break;
9897 case FKCONSTR_ACTION_CASCADE:
9898 fk_trigger->deferrable = false;
9899 fk_trigger->initdeferred = false;
9900 fk_trigger->funcname = SystemFuncName("RI_FKey_cascade_del");
9901 break;
9902 case FKCONSTR_ACTION_SETNULL:
9903 fk_trigger->deferrable = false;
9904 fk_trigger->initdeferred = false;
9905 fk_trigger->funcname = SystemFuncName("RI_FKey_setnull_del");
9906 break;
9907 case FKCONSTR_ACTION_SETDEFAULT:
9908 fk_trigger->deferrable = false;
9909 fk_trigger->initdeferred = false;
9910 fk_trigger->funcname = SystemFuncName("RI_FKey_setdefault_del");
9911 break;
9912 default:
9913 elog(ERROR, "unrecognized FK action type: %d",
9914 (int) fkconstraint->fk_del_action);
9915 break;
9916 }
9917 fk_trigger->args = NIL;
9918
9919 (void) CreateTrigger(fk_trigger, NULL, refRelOid, RelationGetRelid(rel),
9920 constraintOid,
9921 indexOid, InvalidOid, InvalidOid, NULL, true, false);
9922
9923 /* Make changes-so-far visible */
9924 CommandCounterIncrement();
9925
9926 /*
9927 * Build and execute a CREATE CONSTRAINT TRIGGER statement for the ON
9928 * UPDATE action on the referenced table.
9929 */
9930 fk_trigger = makeNode(CreateTrigStmt);
9931 fk_trigger->trigname = "RI_ConstraintTrigger_a";
9932 fk_trigger->relation = NULL;
9933 fk_trigger->row = true;
9934 fk_trigger->timing = TRIGGER_TYPE_AFTER;
9935 fk_trigger->events = TRIGGER_TYPE_UPDATE;
9936 fk_trigger->columns = NIL;
9937 fk_trigger->transitionRels = NIL;
9938 fk_trigger->whenClause = NULL;
9939 fk_trigger->isconstraint = true;
9940 fk_trigger->constrrel = NULL;
9941 switch (fkconstraint->fk_upd_action)
9942 {
9943 case FKCONSTR_ACTION_NOACTION:
9944 fk_trigger->deferrable = fkconstraint->deferrable;
9945 fk_trigger->initdeferred = fkconstraint->initdeferred;
9946 fk_trigger->funcname = SystemFuncName("RI_FKey_noaction_upd");
9947 break;
9948 case FKCONSTR_ACTION_RESTRICT:
9949 fk_trigger->deferrable = false;
9950 fk_trigger->initdeferred = false;
9951 fk_trigger->funcname = SystemFuncName("RI_FKey_restrict_upd");
9952 break;
9953 case FKCONSTR_ACTION_CASCADE:
9954 fk_trigger->deferrable = false;
9955 fk_trigger->initdeferred = false;
9956 fk_trigger->funcname = SystemFuncName("RI_FKey_cascade_upd");
9957 break;
9958 case FKCONSTR_ACTION_SETNULL:
9959 fk_trigger->deferrable = false;
9960 fk_trigger->initdeferred = false;
9961 fk_trigger->funcname = SystemFuncName("RI_FKey_setnull_upd");
9962 break;
9963 case FKCONSTR_ACTION_SETDEFAULT:
9964 fk_trigger->deferrable = false;
9965 fk_trigger->initdeferred = false;
9966 fk_trigger->funcname = SystemFuncName("RI_FKey_setdefault_upd");
9967 break;
9968 default:
9969 elog(ERROR, "unrecognized FK action type: %d",
9970 (int) fkconstraint->fk_upd_action);
9971 break;
9972 }
9973 fk_trigger->args = NIL;
9974
9975 (void) CreateTrigger(fk_trigger, NULL, refRelOid, RelationGetRelid(rel),
9976 constraintOid,
9977 indexOid, InvalidOid, InvalidOid, NULL, true, false);
9978}
9979
9980/*
9981 * createForeignKeyCheckTriggers
9982 * Create the referencing-side "check" triggers that implement a foreign
9983 * key.
9984 */
9985static void
9986createForeignKeyCheckTriggers(Oid myRelOid, Oid refRelOid,
9987 Constraint *fkconstraint, Oid constraintOid,
9988 Oid indexOid)
9989{
9990 CreateFKCheckTrigger(myRelOid, refRelOid, fkconstraint, constraintOid,
9991 indexOid, true);
9992 CreateFKCheckTrigger(myRelOid, refRelOid, fkconstraint, constraintOid,
9993 indexOid, false);
9994}
9995
9996/*
9997 * ALTER TABLE DROP CONSTRAINT
9998 *
9999 * Like DROP COLUMN, we can't use the normal ALTER TABLE recursion mechanism.
10000 */
10001static void
10002ATExecDropConstraint(Relation rel, const char *constrName,
10003 DropBehavior behavior,
10004 bool recurse, bool recursing,
10005 bool missing_ok, LOCKMODE lockmode)
10006{
10007 List *children;
10008 ListCell *child;
10009 Relation conrel;
10010 Form_pg_constraint con;
10011 SysScanDesc scan;
10012 ScanKeyData skey[3];
10013 HeapTuple tuple;
10014 bool found = false;
10015 bool is_no_inherit_constraint = false;
10016 char contype;
10017
10018 /* At top level, permission check was done in ATPrepCmd, else do it */
10019 if (recursing)
10020 ATSimplePermissions(rel, ATT_TABLE | ATT_FOREIGN_TABLE);
10021
10022 conrel = table_open(ConstraintRelationId, RowExclusiveLock);
10023
10024 /*
10025 * Find and drop the target constraint
10026 */
10027 ScanKeyInit(&skey[0],
10028 Anum_pg_constraint_conrelid,
10029 BTEqualStrategyNumber, F_OIDEQ,
10030 ObjectIdGetDatum(RelationGetRelid(rel)));
10031 ScanKeyInit(&skey[1],
10032 Anum_pg_constraint_contypid,
10033 BTEqualStrategyNumber, F_OIDEQ,
10034 ObjectIdGetDatum(InvalidOid));
10035 ScanKeyInit(&skey[2],
10036 Anum_pg_constraint_conname,
10037 BTEqualStrategyNumber, F_NAMEEQ,
10038 CStringGetDatum(constrName));
10039 scan = systable_beginscan(conrel, ConstraintRelidTypidNameIndexId,
10040 true, NULL, 3, skey);
10041
10042 /* There can be at most one matching row */
10043 if (HeapTupleIsValid(tuple = systable_getnext(scan)))
10044 {
10045 ObjectAddress conobj;
10046
10047 con = (Form_pg_constraint) GETSTRUCT(tuple);
10048
10049 /* Don't drop inherited constraints */
10050 if (con->coninhcount > 0 && !recursing)
10051 ereport(ERROR,
10052 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
10053 errmsg("cannot drop inherited constraint \"%s\" of relation \"%s\"",
10054 constrName, RelationGetRelationName(rel))));
10055
10056 is_no_inherit_constraint = con->connoinherit;
10057 contype = con->contype;
10058
10059 /*
10060 * If it's a foreign-key constraint, we'd better lock the referenced
10061 * table and check that that's not in use, just as we've already done
10062 * for the constrained table (else we might, eg, be dropping a trigger
10063 * that has unfired events). But we can/must skip that in the
10064 * self-referential case.
10065 */
10066 if (contype == CONSTRAINT_FOREIGN &&
10067 con->confrelid != RelationGetRelid(rel))
10068 {
10069 Relation frel;
10070
10071 /* Must match lock taken by RemoveTriggerById: */
10072 frel = table_open(con->confrelid, AccessExclusiveLock);
10073 CheckTableNotInUse(frel, "ALTER TABLE");
10074 table_close(frel, NoLock);
10075 }
10076
10077 /*
10078 * Perform the actual constraint deletion
10079 */
10080 conobj.classId = ConstraintRelationId;
10081 conobj.objectId = con->oid;
10082 conobj.objectSubId = 0;
10083
10084 performDeletion(&conobj, behavior, 0);
10085
10086 found = true;
10087 }
10088
10089 systable_endscan(scan);
10090
10091 if (!found)
10092 {
10093 if (!missing_ok)
10094 {
10095 ereport(ERROR,
10096 (errcode(ERRCODE_UNDEFINED_OBJECT),
10097 errmsg("constraint \"%s\" of relation \"%s\" does not exist",
10098 constrName, RelationGetRelationName(rel))));
10099 }
10100 else
10101 {
10102 ereport(NOTICE,
10103 (errmsg("constraint \"%s\" of relation \"%s\" does not exist, skipping",
10104 constrName, RelationGetRelationName(rel))));
10105 table_close(conrel, RowExclusiveLock);
10106 return;
10107 }
10108 }
10109
10110 /*
10111 * For partitioned tables, non-CHECK inherited constraints are dropped via
10112 * the dependency mechanism, so we're done here.
10113 */
10114 if (contype != CONSTRAINT_CHECK &&
10115 rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
10116 {
10117 table_close(conrel, RowExclusiveLock);
10118 return;
10119 }
10120
10121 /*
10122 * Propagate to children as appropriate. Unlike most other ALTER
10123 * routines, we have to do this one level of recursion at a time; we can't
10124 * use find_all_inheritors to do it in one pass.
10125 */
10126 if (!is_no_inherit_constraint)
10127 children = find_inheritance_children(RelationGetRelid(rel), lockmode);
10128 else
10129 children = NIL;
10130
10131 /*
10132 * For a partitioned table, if partitions exist and we are told not to
10133 * recurse, it's a user error. It doesn't make sense to have a constraint
10134 * be defined only on the parent, especially if it's a partitioned table.
10135 */
10136 if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE &&
10137 children != NIL && !recurse)
10138 ereport(ERROR,
10139 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
10140 errmsg("cannot remove constraint from only the partitioned table when partitions exist"),
10141 errhint("Do not specify the ONLY keyword.")));
10142
10143 foreach(child, children)
10144 {
10145 Oid childrelid = lfirst_oid(child);
10146 Relation childrel;
10147 HeapTuple copy_tuple;
10148
10149 /* find_inheritance_children already got lock */
10150 childrel = table_open(childrelid, NoLock);
10151 CheckTableNotInUse(childrel, "ALTER TABLE");
10152
10153 ScanKeyInit(&skey[0],
10154 Anum_pg_constraint_conrelid,
10155 BTEqualStrategyNumber, F_OIDEQ,
10156 ObjectIdGetDatum(childrelid));
10157 ScanKeyInit(&skey[1],
10158 Anum_pg_constraint_contypid,
10159 BTEqualStrategyNumber, F_OIDEQ,
10160 ObjectIdGetDatum(InvalidOid));
10161 ScanKeyInit(&skey[2],
10162 Anum_pg_constraint_conname,
10163 BTEqualStrategyNumber, F_NAMEEQ,
10164 CStringGetDatum(constrName));
10165 scan = systable_beginscan(conrel, ConstraintRelidTypidNameIndexId,
10166 true, NULL, 3, skey);
10167
10168 /* There can be at most one matching row */
10169 if (!HeapTupleIsValid(tuple = systable_getnext(scan)))
10170 ereport(ERROR,
10171 (errcode(ERRCODE_UNDEFINED_OBJECT),
10172 errmsg("constraint \"%s\" of relation \"%s\" does not exist",
10173 constrName,
10174 RelationGetRelationName(childrel))));
10175
10176 copy_tuple = heap_copytuple(tuple);
10177
10178 systable_endscan(scan);
10179
10180 con = (Form_pg_constraint) GETSTRUCT(copy_tuple);
10181
10182 /* Right now only CHECK constraints can be inherited */
10183 if (con->contype != CONSTRAINT_CHECK)
10184 elog(ERROR, "inherited constraint is not a CHECK constraint");
10185
10186 if (con->coninhcount <= 0) /* shouldn't happen */
10187 elog(ERROR, "relation %u has non-inherited constraint \"%s\"",
10188 childrelid, constrName);
10189
10190 if (recurse)
10191 {
10192 /*
10193 * If the child constraint has other definition sources, just
10194 * decrement its inheritance count; if not, recurse to delete it.
10195 */
10196 if (con->coninhcount == 1 && !con->conislocal)
10197 {
10198 /* Time to delete this child constraint, too */
10199 ATExecDropConstraint(childrel, constrName, behavior,
10200 true, true,
10201 false, lockmode);
10202 }
10203 else
10204 {
10205 /* Child constraint must survive my deletion */
10206 con->coninhcount--;
10207 CatalogTupleUpdate(conrel, &copy_tuple->t_self, copy_tuple);
10208
10209 /* Make update visible */
10210 CommandCounterIncrement();
10211 }
10212 }
10213 else
10214 {
10215 /*
10216 * If we were told to drop ONLY in this table (no recursion), we
10217 * need to mark the inheritors' constraints as locally defined
10218 * rather than inherited.
10219 */
10220 con->coninhcount--;
10221 con->conislocal = true;
10222
10223 CatalogTupleUpdate(conrel, &copy_tuple->t_self, copy_tuple);
10224
10225 /* Make update visible */
10226 CommandCounterIncrement();
10227 }
10228
10229 heap_freetuple(copy_tuple);
10230
10231 table_close(childrel, NoLock);
10232 }
10233
10234 table_close(conrel, RowExclusiveLock);
10235}
10236
10237/*
10238 * ALTER COLUMN TYPE
10239 */
10240static void
10241ATPrepAlterColumnType(List **wqueue,
10242 AlteredTableInfo *tab, Relation rel,
10243 bool recurse, bool recursing,
10244 AlterTableCmd *cmd, LOCKMODE lockmode)
10245{
10246 char *colName = cmd->name;
10247 ColumnDef *def = (ColumnDef *) cmd->def;
10248 TypeName *typeName = def->typeName;
10249 Node *transform = def->cooked_default;
10250 HeapTuple tuple;
10251 Form_pg_attribute attTup;
10252 AttrNumber attnum;
10253 Oid targettype;
10254 int32 targettypmod;
10255 Oid targetcollid;
10256 NewColumnValue *newval;
10257 ParseState *pstate = make_parsestate(NULL);
10258 AclResult aclresult;
10259 bool is_expr;
10260
10261 if (rel->rd_rel->reloftype && !recursing)
10262 ereport(ERROR,
10263 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
10264 errmsg("cannot alter column type of typed table")));
10265
10266 /* lookup the attribute so we can check inheritance status */
10267 tuple = SearchSysCacheAttName(RelationGetRelid(rel), colName);
10268 if (!HeapTupleIsValid(tuple))
10269 ereport(ERROR,
10270 (errcode(ERRCODE_UNDEFINED_COLUMN),
10271 errmsg("column \"%s\" of relation \"%s\" does not exist",
10272 colName, RelationGetRelationName(rel))));
10273 attTup = (Form_pg_attribute) GETSTRUCT(tuple);
10274 attnum = attTup->attnum;
10275
10276 /* Can't alter a system attribute */
10277 if (attnum <= 0)
10278 ereport(ERROR,
10279 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
10280 errmsg("cannot alter system column \"%s\"",
10281 colName)));
10282
10283 /*
10284 * Don't alter inherited columns. At outer level, there had better not be
10285 * any inherited definition; when recursing, we assume this was checked at
10286 * the parent level (see below).
10287 */
10288 if (attTup->attinhcount > 0 && !recursing)
10289 ereport(ERROR,
10290 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
10291 errmsg("cannot alter inherited column \"%s\"",
10292 colName)));
10293
10294 /* Don't alter columns used in the partition key */
10295 if (has_partition_attrs(rel,
10296 bms_make_singleton(attnum - FirstLowInvalidHeapAttributeNumber),
10297 &is_expr))
10298 ereport(ERROR,
10299 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
10300 errmsg("cannot alter column \"%s\" because it is part of the partition key of relation \"%s\"",
10301 colName, RelationGetRelationName(rel))));
10302
10303 /* Look up the target type */
10304 typenameTypeIdAndMod(NULL, typeName, &targettype, &targettypmod);
10305
10306 aclresult = pg_type_aclcheck(targettype, GetUserId(), ACL_USAGE);
10307 if (aclresult != ACLCHECK_OK)
10308 aclcheck_error_type(aclresult, targettype);
10309
10310 /* And the collation */
10311 targetcollid = GetColumnDefCollation(NULL, def, targettype);
10312
10313 /* make sure datatype is legal for a column */
10314 CheckAttributeType(colName, targettype, targetcollid,
10315 list_make1_oid(rel->rd_rel->reltype),
10316 0);
10317
10318 if (tab->relkind == RELKIND_RELATION ||
10319 tab->relkind == RELKIND_PARTITIONED_TABLE)
10320 {
10321 /*
10322 * Set up an expression to transform the old data value to the new
10323 * type. If a USING option was given, use the expression as
10324 * transformed by transformAlterTableStmt, else just take the old
10325 * value and try to coerce it. We do this first so that type
10326 * incompatibility can be detected before we waste effort, and because
10327 * we need the expression to be parsed against the original table row
10328 * type.
10329 */
10330 if (!transform)
10331 {
10332 transform = (Node *) makeVar(1, attnum,
10333 attTup->atttypid, attTup->atttypmod,
10334 attTup->attcollation,
10335 0);
10336 }
10337
10338 transform = coerce_to_target_type(pstate,
10339 transform, exprType(transform),
10340 targettype, targettypmod,
10341 COERCION_ASSIGNMENT,
10342 COERCE_IMPLICIT_CAST,
10343 -1);
10344 if (transform == NULL)
10345 {
10346 /* error text depends on whether USING was specified or not */
10347 if (def->cooked_default != NULL)
10348 ereport(ERROR,
10349 (errcode(ERRCODE_DATATYPE_MISMATCH),
10350 errmsg("result of USING clause for column \"%s\""
10351 " cannot be cast automatically to type %s",
10352 colName, format_type_be(targettype)),
10353 errhint("You might need to add an explicit cast.")));
10354 else
10355 ereport(ERROR,
10356 (errcode(ERRCODE_DATATYPE_MISMATCH),
10357 errmsg("column \"%s\" cannot be cast automatically to type %s",
10358 colName, format_type_be(targettype)),
10359 /* translator: USING is SQL, don't translate it */
10360 errhint("You might need to specify \"USING %s::%s\".",
10361 quote_identifier(colName),
10362 format_type_with_typemod(targettype,
10363 targettypmod))));
10364 }
10365
10366 /* Fix collations after all else */
10367 assign_expr_collations(pstate, transform);
10368
10369 /* Plan the expr now so we can accurately assess the need to rewrite. */
10370 transform = (Node *) expression_planner((Expr *) transform);
10371
10372 /*
10373 * Add a work queue item to make ATRewriteTable update the column
10374 * contents.
10375 */
10376 newval = (NewColumnValue *) palloc0(sizeof(NewColumnValue));
10377 newval->attnum = attnum;
10378 newval->expr = (Expr *) transform;
10379
10380 tab->newvals = lappend(tab->newvals, newval);
10381 if (ATColumnChangeRequiresRewrite(transform, attnum))
10382 tab->rewrite |= AT_REWRITE_COLUMN_REWRITE;
10383 }
10384 else if (transform)
10385 ereport(ERROR,
10386 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
10387 errmsg("\"%s\" is not a table",
10388 RelationGetRelationName(rel))));
10389
10390 if (tab->relkind == RELKIND_COMPOSITE_TYPE ||
10391 tab->relkind == RELKIND_FOREIGN_TABLE)
10392 {
10393 /*
10394 * For composite types, do this check now. Tables will check it later
10395 * when the table is being rewritten.
10396 */
10397 find_composite_type_dependencies(rel->rd_rel->reltype, rel, NULL);
10398 }
10399
10400 ReleaseSysCache(tuple);
10401
10402 /*
10403 * Recurse manually by queueing a new command for each child, if
10404 * necessary. We cannot apply ATSimpleRecursion here because we need to
10405 * remap attribute numbers in the USING expression, if any.
10406 *
10407 * If we are told not to recurse, there had better not be any child
10408 * tables; else the alter would put them out of step.
10409 */
10410 if (recurse)
10411 {
10412 Oid relid = RelationGetRelid(rel);
10413 List *child_oids,
10414 *child_numparents;
10415 ListCell *lo,
10416 *li;
10417
10418 child_oids = find_all_inheritors(relid, lockmode,
10419 &child_numparents);
10420
10421 /*
10422 * find_all_inheritors does the recursive search of the inheritance
10423 * hierarchy, so all we have to do is process all of the relids in the
10424 * list that it returns.
10425 */
10426 forboth(lo, child_oids, li, child_numparents)
10427 {
10428 Oid childrelid = lfirst_oid(lo);
10429 int numparents = lfirst_int(li);
10430 Relation childrel;
10431 HeapTuple childtuple;
10432 Form_pg_attribute childattTup;
10433
10434 if (childrelid == relid)
10435 continue;
10436
10437 /* find_all_inheritors already got lock */
10438 childrel = relation_open(childrelid, NoLock);
10439 CheckTableNotInUse(childrel, "ALTER TABLE");
10440
10441 /*
10442 * Verify that the child doesn't have any inherited definitions of
10443 * this column that came from outside this inheritance hierarchy.
10444 * (renameatt makes a similar test, though in a different way
10445 * because of its different recursion mechanism.)
10446 */
10447 childtuple = SearchSysCacheAttName(RelationGetRelid(childrel),
10448 colName);
10449 if (!HeapTupleIsValid(childtuple))
10450 ereport(ERROR,
10451 (errcode(ERRCODE_UNDEFINED_COLUMN),
10452 errmsg("column \"%s\" of relation \"%s\" does not exist",
10453 colName, RelationGetRelationName(childrel))));
10454 childattTup = (Form_pg_attribute) GETSTRUCT(childtuple);
10455
10456 if (childattTup->attinhcount > numparents)
10457 ereport(ERROR,
10458 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
10459 errmsg("cannot alter inherited column \"%s\" of relation \"%s\"",
10460 colName, RelationGetRelationName(childrel))));
10461
10462 ReleaseSysCache(childtuple);
10463
10464 /*
10465 * Remap the attribute numbers. If no USING expression was
10466 * specified, there is no need for this step.
10467 */
10468 if (def->cooked_default)
10469 {
10470 AttrNumber *attmap;
10471 bool found_whole_row;
10472
10473 /* create a copy to scribble on */
10474 cmd = copyObject(cmd);
10475
10476 attmap = convert_tuples_by_name_map(RelationGetDescr(childrel),
10477 RelationGetDescr(rel),
10478 gettext_noop("could not convert row type"));
10479 ((ColumnDef *) cmd->def)->cooked_default =
10480 map_variable_attnos(def->cooked_default,
10481 1, 0,
10482 attmap, RelationGetDescr(rel)->natts,
10483 InvalidOid, &found_whole_row);
10484 if (found_whole_row)
10485 ereport(ERROR,
10486 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
10487 errmsg("cannot convert whole-row table reference"),
10488 errdetail("USING expression contains a whole-row table reference.")));
10489 pfree(attmap);
10490 }
10491 ATPrepCmd(wqueue, childrel, cmd, false, true, lockmode);
10492 relation_close(childrel, NoLock);
10493 }
10494 }
10495 else if (!recursing &&
10496 find_inheritance_children(RelationGetRelid(rel), NoLock) != NIL)
10497 ereport(ERROR,
10498 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
10499 errmsg("type of inherited column \"%s\" must be changed in child tables too",
10500 colName)));
10501
10502 if (tab->relkind == RELKIND_COMPOSITE_TYPE)
10503 ATTypedTableRecursion(wqueue, rel, cmd, lockmode);
10504}
10505
10506/*
10507 * When the data type of a column is changed, a rewrite might not be required
10508 * if the new type is sufficiently identical to the old one, and the USING
10509 * clause isn't trying to insert some other value. It's safe to skip the
10510 * rewrite in these cases:
10511 *
10512 * - the old type is binary coercible to the new type
10513 * - the new type is an unconstrained domain over the old type
10514 * - {NEW,OLD} or {OLD,NEW} is {timestamptz,timestamp} and the timezone is UTC
10515 *
10516 * In the case of a constrained domain, we could get by with scanning the
10517 * table and checking the constraint rather than actually rewriting it, but we
10518 * don't currently try to do that.
10519 */
10520static bool
10521ATColumnChangeRequiresRewrite(Node *expr, AttrNumber varattno)
10522{
10523 Assert(expr != NULL);
10524
10525 for (;;)
10526 {
10527 /* only one varno, so no need to check that */
10528 if (IsA(expr, Var) &&((Var *) expr)->varattno == varattno)
10529 return false;
10530 else if (IsA(expr, RelabelType))
10531 expr = (Node *) ((RelabelType *) expr)->arg;
10532 else if (IsA(expr, CoerceToDomain))
10533 {
10534 CoerceToDomain *d = (CoerceToDomain *) expr;
10535
10536 if (DomainHasConstraints(d->resulttype))
10537 return true;
10538 expr = (Node *) d->arg;
10539 }
10540 else if (IsA(expr, FuncExpr))
10541 {
10542 FuncExpr *f = (FuncExpr *) expr;
10543
10544 switch (f->funcid)
10545 {
10546 case F_TIMESTAMPTZ_TIMESTAMP:
10547 case F_TIMESTAMP_TIMESTAMPTZ:
10548 if (TimestampTimestampTzRequiresRewrite())
10549 return true;
10550 else
10551 expr = linitial(f->args);
10552 break;
10553 default:
10554 return true;
10555 }
10556 }
10557 else
10558 return true;
10559 }
10560}
10561
10562/*
10563 * ALTER COLUMN .. SET DATA TYPE
10564 *
10565 * Return the address of the modified column.
10566 */
10567static ObjectAddress
10568ATExecAlterColumnType(AlteredTableInfo *tab, Relation rel,
10569 AlterTableCmd *cmd, LOCKMODE lockmode)
10570{
10571 char *colName = cmd->name;
10572 ColumnDef *def = (ColumnDef *) cmd->def;
10573 TypeName *typeName = def->typeName;
10574 HeapTuple heapTup;
10575 Form_pg_attribute attTup,
10576 attOldTup;
10577 AttrNumber attnum;
10578 HeapTuple typeTuple;
10579 Form_pg_type tform;
10580 Oid targettype;
10581 int32 targettypmod;
10582 Oid targetcollid;
10583 Node *defaultexpr;
10584 Relation attrelation;
10585 Relation depRel;
10586 ScanKeyData key[3];
10587 SysScanDesc scan;
10588 HeapTuple depTup;
10589 ObjectAddress address;
10590
10591 /*
10592 * Clear all the missing values if we're rewriting the table, since this
10593 * renders them pointless.
10594 */
10595 if (tab->rewrite)
10596 {
10597 Relation newrel;
10598
10599 newrel = table_open(RelationGetRelid(rel), NoLock);
10600 RelationClearMissing(newrel);
10601 relation_close(newrel, NoLock);
10602 /* make sure we don't conflict with later attribute modifications */
10603 CommandCounterIncrement();
10604 }
10605
10606 attrelation = table_open(AttributeRelationId, RowExclusiveLock);
10607
10608 /* Look up the target column */
10609 heapTup = SearchSysCacheCopyAttName(RelationGetRelid(rel), colName);
10610 if (!HeapTupleIsValid(heapTup)) /* shouldn't happen */
10611 ereport(ERROR,
10612 (errcode(ERRCODE_UNDEFINED_COLUMN),
10613 errmsg("column \"%s\" of relation \"%s\" does not exist",
10614 colName, RelationGetRelationName(rel))));
10615 attTup = (Form_pg_attribute) GETSTRUCT(heapTup);
10616 attnum = attTup->attnum;
10617 attOldTup = TupleDescAttr(tab->oldDesc, attnum - 1);
10618
10619 /* Check for multiple ALTER TYPE on same column --- can't cope */
10620 if (attTup->atttypid != attOldTup->atttypid ||
10621 attTup->atttypmod != attOldTup->atttypmod)
10622 ereport(ERROR,
10623 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
10624 errmsg("cannot alter type of column \"%s\" twice",
10625 colName)));
10626
10627 /* Look up the target type (should not fail, since prep found it) */
10628 typeTuple = typenameType(NULL, typeName, &targettypmod);
10629 tform = (Form_pg_type) GETSTRUCT(typeTuple);
10630 targettype = tform->oid;
10631 /* And the collation */
10632 targetcollid = GetColumnDefCollation(NULL, def, targettype);
10633
10634 /*
10635 * If there is a default expression for the column, get it and ensure we
10636 * can coerce it to the new datatype. (We must do this before changing
10637 * the column type, because build_column_default itself will try to
10638 * coerce, and will not issue the error message we want if it fails.)
10639 *
10640 * We remove any implicit coercion steps at the top level of the old
10641 * default expression; this has been agreed to satisfy the principle of
10642 * least surprise. (The conversion to the new column type should act like
10643 * it started from what the user sees as the stored expression, and the
10644 * implicit coercions aren't going to be shown.)
10645 */
10646 if (attTup->atthasdef)
10647 {
10648 defaultexpr = build_column_default(rel, attnum);
10649 Assert(defaultexpr);
10650 defaultexpr = strip_implicit_coercions(defaultexpr);
10651 defaultexpr = coerce_to_target_type(NULL, /* no UNKNOWN params */
10652 defaultexpr, exprType(defaultexpr),
10653 targettype, targettypmod,
10654 COERCION_ASSIGNMENT,
10655 COERCE_IMPLICIT_CAST,
10656 -1);
10657 if (defaultexpr == NULL)
10658 {
10659 if (attTup->attgenerated)
10660 ereport(ERROR,
10661 (errcode(ERRCODE_DATATYPE_MISMATCH),
10662 errmsg("generation expression for column \"%s\" cannot be cast automatically to type %s",
10663 colName, format_type_be(targettype))));
10664 else
10665 ereport(ERROR,
10666 (errcode(ERRCODE_DATATYPE_MISMATCH),
10667 errmsg("default for column \"%s\" cannot be cast automatically to type %s",
10668 colName, format_type_be(targettype))));
10669 }
10670 }
10671 else
10672 defaultexpr = NULL;
10673
10674 /*
10675 * Find everything that depends on the column (constraints, indexes, etc),
10676 * and record enough information to let us recreate the objects.
10677 *
10678 * The actual recreation does not happen here, but only after we have
10679 * performed all the individual ALTER TYPE operations. We have to save
10680 * the info before executing ALTER TYPE, though, else the deparser will
10681 * get confused.
10682 */
10683 depRel = table_open(DependRelationId, RowExclusiveLock);
10684
10685 ScanKeyInit(&key[0],
10686 Anum_pg_depend_refclassid,
10687 BTEqualStrategyNumber, F_OIDEQ,
10688 ObjectIdGetDatum(RelationRelationId));
10689 ScanKeyInit(&key[1],
10690 Anum_pg_depend_refobjid,
10691 BTEqualStrategyNumber, F_OIDEQ,
10692 ObjectIdGetDatum(RelationGetRelid(rel)));
10693 ScanKeyInit(&key[2],
10694 Anum_pg_depend_refobjsubid,
10695 BTEqualStrategyNumber, F_INT4EQ,
10696 Int32GetDatum((int32) attnum));
10697
10698 scan = systable_beginscan(depRel, DependReferenceIndexId, true,
10699 NULL, 3, key);
10700
10701 while (HeapTupleIsValid(depTup = systable_getnext(scan)))
10702 {
10703 Form_pg_depend foundDep = (Form_pg_depend) GETSTRUCT(depTup);
10704 ObjectAddress foundObject;
10705
10706 /* We don't expect any PIN dependencies on columns */
10707 if (foundDep->deptype == DEPENDENCY_PIN)
10708 elog(ERROR, "cannot alter type of a pinned column");
10709
10710 foundObject.classId = foundDep->classid;
10711 foundObject.objectId = foundDep->objid;
10712 foundObject.objectSubId = foundDep->objsubid;
10713
10714 switch (getObjectClass(&foundObject))
10715 {
10716 case OCLASS_CLASS:
10717 {
10718 char relKind = get_rel_relkind(foundObject.objectId);
10719
10720 if (relKind == RELKIND_INDEX ||
10721 relKind == RELKIND_PARTITIONED_INDEX)
10722 {
10723 Assert(foundObject.objectSubId == 0);
10724 RememberIndexForRebuilding(foundObject.objectId, tab);
10725 }
10726 else if (relKind == RELKIND_SEQUENCE)
10727 {
10728 /*
10729 * This must be a SERIAL column's sequence. We need
10730 * not do anything to it.
10731 */
10732 Assert(foundObject.objectSubId == 0);
10733 }
10734 else if (relKind == RELKIND_RELATION &&
10735 foundObject.objectSubId != 0 &&
10736 get_attgenerated(foundObject.objectId, foundObject.objectSubId))
10737 {
10738 /*
10739 * Changing the type of a column that is used by a
10740 * generated column is not allowed by SQL standard. It
10741 * might be doable with some thinking and effort.
10742 */
10743 ereport(ERROR,
10744 (errcode(ERRCODE_SYNTAX_ERROR),
10745 errmsg("cannot alter type of a column used by a generated column"),
10746 errdetail("Column \"%s\" is used by generated column \"%s\".",
10747 colName, get_attname(foundObject.objectId, foundObject.objectSubId, false))));
10748 }
10749 else
10750 {
10751 /* Not expecting any other direct dependencies... */
10752 elog(ERROR, "unexpected object depending on column: %s",
10753 getObjectDescription(&foundObject));
10754 }
10755 break;
10756 }
10757
10758 case OCLASS_CONSTRAINT:
10759 Assert(foundObject.objectSubId == 0);
10760 RememberConstraintForRebuilding(foundObject.objectId, tab);
10761 break;
10762
10763 case OCLASS_REWRITE:
10764 /* XXX someday see if we can cope with revising views */
10765 ereport(ERROR,
10766 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
10767 errmsg("cannot alter type of a column used by a view or rule"),
10768 errdetail("%s depends on column \"%s\"",
10769 getObjectDescription(&foundObject),
10770 colName)));
10771 break;
10772
10773 case OCLASS_TRIGGER:
10774
10775 /*
10776 * A trigger can depend on a column because the column is
10777 * specified as an update target, or because the column is
10778 * used in the trigger's WHEN condition. The first case would
10779 * not require any extra work, but the second case would
10780 * require updating the WHEN expression, which will take a
10781 * significant amount of new code. Since we can't easily tell
10782 * which case applies, we punt for both. FIXME someday.
10783 */
10784 ereport(ERROR,
10785 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
10786 errmsg("cannot alter type of a column used in a trigger definition"),
10787 errdetail("%s depends on column \"%s\"",
10788 getObjectDescription(&foundObject),
10789 colName)));
10790 break;
10791
10792 case OCLASS_POLICY:
10793
10794 /*
10795 * A policy can depend on a column because the column is
10796 * specified in the policy's USING or WITH CHECK qual
10797 * expressions. It might be possible to rewrite and recheck
10798 * the policy expression, but punt for now. It's certainly
10799 * easy enough to remove and recreate the policy; still, FIXME
10800 * someday.
10801 */
10802 ereport(ERROR,
10803 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
10804 errmsg("cannot alter type of a column used in a policy definition"),
10805 errdetail("%s depends on column \"%s\"",
10806 getObjectDescription(&foundObject),
10807 colName)));
10808 break;
10809
10810 case OCLASS_DEFAULT:
10811
10812 /*
10813 * Ignore the column's default expression, since we will fix
10814 * it below.
10815 */
10816 Assert(defaultexpr);
10817 break;
10818
10819 case OCLASS_STATISTIC_EXT:
10820
10821 /*
10822 * Give the extended-stats machinery a chance to fix anything
10823 * that this column type change would break.
10824 */
10825 UpdateStatisticsForTypeChange(foundObject.objectId,
10826 RelationGetRelid(rel), attnum,
10827 attTup->atttypid, targettype);
10828 break;
10829
10830 case OCLASS_PROC:
10831 case OCLASS_TYPE:
10832 case OCLASS_CAST:
10833 case OCLASS_COLLATION:
10834 case OCLASS_CONVERSION:
10835 case OCLASS_LANGUAGE:
10836 case OCLASS_LARGEOBJECT:
10837 case OCLASS_OPERATOR:
10838 case OCLASS_OPCLASS:
10839 case OCLASS_OPFAMILY:
10840 case OCLASS_AM:
10841 case OCLASS_AMOP:
10842 case OCLASS_AMPROC:
10843 case OCLASS_SCHEMA:
10844 case OCLASS_TSPARSER:
10845 case OCLASS_TSDICT:
10846 case OCLASS_TSTEMPLATE:
10847 case OCLASS_TSCONFIG:
10848 case OCLASS_ROLE:
10849 case OCLASS_DATABASE:
10850 case OCLASS_TBLSPACE:
10851 case OCLASS_FDW:
10852 case OCLASS_FOREIGN_SERVER:
10853 case OCLASS_USER_MAPPING:
10854 case OCLASS_DEFACL:
10855 case OCLASS_EXTENSION:
10856 case OCLASS_EVENT_TRIGGER:
10857 case OCLASS_PUBLICATION:
10858 case OCLASS_PUBLICATION_REL:
10859 case OCLASS_SUBSCRIPTION:
10860 case OCLASS_TRANSFORM:
10861
10862 /*
10863 * We don't expect any of these sorts of objects to depend on
10864 * a column.
10865 */
10866 elog(ERROR, "unexpected object depending on column: %s",
10867 getObjectDescription(&foundObject));
10868 break;
10869
10870 /*
10871 * There's intentionally no default: case here; we want the
10872 * compiler to warn if a new OCLASS hasn't been handled above.
10873 */
10874 }
10875 }
10876
10877 systable_endscan(scan);
10878
10879 /*
10880 * Now scan for dependencies of this column on other things. The only
10881 * thing we should find is the dependency on the column datatype, which we
10882 * want to remove, possibly a collation dependency, and dependencies on
10883 * other columns if it is a generated column.
10884 */
10885 ScanKeyInit(&key[0],
10886 Anum_pg_depend_classid,
10887 BTEqualStrategyNumber, F_OIDEQ,
10888 ObjectIdGetDatum(RelationRelationId));
10889 ScanKeyInit(&key[1],
10890 Anum_pg_depend_objid,
10891 BTEqualStrategyNumber, F_OIDEQ,
10892 ObjectIdGetDatum(RelationGetRelid(rel)));
10893 ScanKeyInit(&key[2],
10894 Anum_pg_depend_objsubid,
10895 BTEqualStrategyNumber, F_INT4EQ,
10896 Int32GetDatum((int32) attnum));
10897
10898 scan = systable_beginscan(depRel, DependDependerIndexId, true,
10899 NULL, 3, key);
10900
10901 while (HeapTupleIsValid(depTup = systable_getnext(scan)))
10902 {
10903 Form_pg_depend foundDep = (Form_pg_depend) GETSTRUCT(depTup);
10904 ObjectAddress foundObject;
10905
10906 foundObject.classId = foundDep->refclassid;
10907 foundObject.objectId = foundDep->refobjid;
10908 foundObject.objectSubId = foundDep->refobjsubid;
10909
10910 if (foundDep->deptype != DEPENDENCY_NORMAL &&
10911 foundDep->deptype != DEPENDENCY_AUTO)
10912 elog(ERROR, "found unexpected dependency type '%c'",
10913 foundDep->deptype);
10914 if (!(foundDep->refclassid == TypeRelationId &&
10915 foundDep->refobjid == attTup->atttypid) &&
10916 !(foundDep->refclassid == CollationRelationId &&
10917 foundDep->refobjid == attTup->attcollation) &&
10918 !(foundDep->refclassid == RelationRelationId &&
10919 foundDep->refobjid == RelationGetRelid(rel) &&
10920 foundDep->refobjsubid != 0)
10921 )
10922 elog(ERROR, "found unexpected dependency for column: %s",
10923 getObjectDescription(&foundObject));
10924
10925 CatalogTupleDelete(depRel, &depTup->t_self);
10926 }
10927
10928 systable_endscan(scan);
10929
10930 table_close(depRel, RowExclusiveLock);
10931
10932 /*
10933 * Here we go --- change the recorded column type and collation. (Note
10934 * heapTup is a copy of the syscache entry, so okay to scribble on.) First
10935 * fix up the missing value if any.
10936 */
10937 if (attTup->atthasmissing)
10938 {
10939 Datum missingval;
10940 bool missingNull;
10941
10942 /* if rewrite is true the missing value should already be cleared */
10943 Assert(tab->rewrite == 0);
10944
10945 /* Get the missing value datum */
10946 missingval = heap_getattr(heapTup,
10947 Anum_pg_attribute_attmissingval,
10948 attrelation->rd_att,
10949 &missingNull);
10950
10951 /* if it's a null array there is nothing to do */
10952
10953 if (!missingNull)
10954 {
10955 /*
10956 * Get the datum out of the array and repack it in a new array
10957 * built with the new type data. We assume that since the table
10958 * doesn't need rewriting, the actual Datum doesn't need to be
10959 * changed, only the array metadata.
10960 */
10961
10962 int one = 1;
10963 bool isNull;
10964 Datum valuesAtt[Natts_pg_attribute];
10965 bool nullsAtt[Natts_pg_attribute];
10966 bool replacesAtt[Natts_pg_attribute];
10967 HeapTuple newTup;
10968
10969 MemSet(valuesAtt, 0, sizeof(valuesAtt));
10970 MemSet(nullsAtt, false, sizeof(nullsAtt));
10971 MemSet(replacesAtt, false, sizeof(replacesAtt));
10972
10973 missingval = array_get_element(missingval,
10974 1,
10975 &one,
10976 0,
10977 attTup->attlen,
10978 attTup->attbyval,
10979 attTup->attalign,
10980 &isNull);
10981 missingval = PointerGetDatum(
10982 construct_array(&missingval,
10983 1,
10984 targettype,
10985 tform->typlen,
10986 tform->typbyval,
10987 tform->typalign));
10988
10989 valuesAtt[Anum_pg_attribute_attmissingval - 1] = missingval;
10990 replacesAtt[Anum_pg_attribute_attmissingval - 1] = true;
10991 nullsAtt[Anum_pg_attribute_attmissingval - 1] = false;
10992
10993 newTup = heap_modify_tuple(heapTup, RelationGetDescr(attrelation),
10994 valuesAtt, nullsAtt, replacesAtt);
10995 heap_freetuple(heapTup);
10996 heapTup = newTup;
10997 attTup = (Form_pg_attribute) GETSTRUCT(heapTup);
10998 }
10999 }
11000
11001 attTup->atttypid = targettype;
11002 attTup->atttypmod = targettypmod;
11003 attTup->attcollation = targetcollid;
11004 attTup->attndims = list_length(typeName->arrayBounds);
11005 attTup->attlen = tform->typlen;
11006 attTup->attbyval = tform->typbyval;
11007 attTup->attalign = tform->typalign;
11008 attTup->attstorage = tform->typstorage;
11009
11010 ReleaseSysCache(typeTuple);
11011
11012 CatalogTupleUpdate(attrelation, &heapTup->t_self, heapTup);
11013
11014 table_close(attrelation, RowExclusiveLock);
11015
11016 /* Install dependencies on new datatype and collation */
11017 add_column_datatype_dependency(RelationGetRelid(rel), attnum, targettype);
11018 add_column_collation_dependency(RelationGetRelid(rel), attnum, targetcollid);
11019
11020 /*
11021 * Drop any pg_statistic entry for the column, since it's now wrong type
11022 */
11023 RemoveStatistics(RelationGetRelid(rel), attnum);
11024
11025 InvokeObjectPostAlterHook(RelationRelationId,
11026 RelationGetRelid(rel), attnum);
11027
11028 /*
11029 * Update the default, if present, by brute force --- remove and re-add
11030 * the default. Probably unsafe to take shortcuts, since the new version
11031 * may well have additional dependencies. (It's okay to do this now,
11032 * rather than after other ALTER TYPE commands, since the default won't
11033 * depend on other column types.)
11034 */
11035 if (defaultexpr)
11036 {
11037 /* Must make new row visible since it will be updated again */
11038 CommandCounterIncrement();
11039
11040 /*
11041 * We use RESTRICT here for safety, but at present we do not expect
11042 * anything to depend on the default.
11043 */
11044 RemoveAttrDefault(RelationGetRelid(rel), attnum, DROP_RESTRICT, true,
11045 true);
11046
11047 StoreAttrDefault(rel, attnum, defaultexpr, true, false);
11048 }
11049
11050 ObjectAddressSubSet(address, RelationRelationId,
11051 RelationGetRelid(rel), attnum);
11052
11053 /* Cleanup */
11054 heap_freetuple(heapTup);
11055
11056 return address;
11057}
11058
11059/*
11060 * Subroutine for ATExecAlterColumnType: remember that a constraint needs
11061 * to be rebuilt (which we might already know).
11062 */
11063static void
11064RememberConstraintForRebuilding(Oid conoid, AlteredTableInfo *tab)
11065{
11066 /*
11067 * This de-duplication check is critical for two independent reasons: we
11068 * mustn't try to recreate the same constraint twice, and if a constraint
11069 * depends on more than one column whose type is to be altered, we must
11070 * capture its definition string before applying any of the column type
11071 * changes. ruleutils.c will get confused if we ask again later.
11072 */
11073 if (!list_member_oid(tab->changedConstraintOids, conoid))
11074 {
11075 /* OK, capture the constraint's existing definition string */
11076 char *defstring = pg_get_constraintdef_command(conoid);
11077
11078 tab->changedConstraintOids = lappend_oid(tab->changedConstraintOids,
11079 conoid);
11080 tab->changedConstraintDefs = lappend(tab->changedConstraintDefs,
11081 defstring);
11082 }
11083}
11084
11085/*
11086 * Subroutine for ATExecAlterColumnType: remember that an index needs
11087 * to be rebuilt (which we might already know).
11088 */
11089static void
11090RememberIndexForRebuilding(Oid indoid, AlteredTableInfo *tab)
11091{
11092 /*
11093 * This de-duplication check is critical for two independent reasons: we
11094 * mustn't try to recreate the same index twice, and if an index depends
11095 * on more than one column whose type is to be altered, we must capture
11096 * its definition string before applying any of the column type changes.
11097 * ruleutils.c will get confused if we ask again later.
11098 */
11099 if (!list_member_oid(tab->changedIndexOids, indoid))
11100 {
11101 /*
11102 * Before adding it as an index-to-rebuild, we'd better see if it
11103 * belongs to a constraint, and if so rebuild the constraint instead.
11104 * Typically this check fails, because constraint indexes normally
11105 * have only dependencies on their constraint. But it's possible for
11106 * such an index to also have direct dependencies on table columns,
11107 * for example with a partial exclusion constraint.
11108 */
11109 Oid conoid = get_index_constraint(indoid);
11110
11111 if (OidIsValid(conoid))
11112 {
11113 RememberConstraintForRebuilding(conoid, tab);
11114 }
11115 else
11116 {
11117 /* OK, capture the index's existing definition string */
11118 char *defstring = pg_get_indexdef_string(indoid);
11119
11120 tab->changedIndexOids = lappend_oid(tab->changedIndexOids,
11121 indoid);
11122 tab->changedIndexDefs = lappend(tab->changedIndexDefs,
11123 defstring);
11124 }
11125 }
11126}
11127
11128/*
11129 * Cleanup after we've finished all the ALTER TYPE operations for a
11130 * particular relation. We have to drop and recreate all the indexes
11131 * and constraints that depend on the altered columns. We do the
11132 * actual dropping here, but re-creation is managed by adding work
11133 * queue entries to do those steps later.
11134 */
11135static void
11136ATPostAlterTypeCleanup(List **wqueue, AlteredTableInfo *tab, LOCKMODE lockmode)
11137{
11138 ObjectAddress obj;
11139 ObjectAddresses *objects;
11140 ListCell *def_item;
11141 ListCell *oid_item;
11142
11143 /*
11144 * Collect all the constraints and indexes to drop so we can process them
11145 * in a single call. That way we don't have to worry about dependencies
11146 * among them.
11147 */
11148 objects = new_object_addresses();
11149
11150 /*
11151 * Re-parse the index and constraint definitions, and attach them to the
11152 * appropriate work queue entries. We do this before dropping because in
11153 * the case of a FOREIGN KEY constraint, we might not yet have exclusive
11154 * lock on the table the constraint is attached to, and we need to get
11155 * that before reparsing/dropping.
11156 *
11157 * We can't rely on the output of deparsing to tell us which relation to
11158 * operate on, because concurrent activity might have made the name
11159 * resolve differently. Instead, we've got to use the OID of the
11160 * constraint or index we're processing to figure out which relation to
11161 * operate on.
11162 */
11163 forboth(oid_item, tab->changedConstraintOids,
11164 def_item, tab->changedConstraintDefs)
11165 {
11166 Oid oldId = lfirst_oid(oid_item);
11167 HeapTuple tup;
11168 Form_pg_constraint con;
11169 Oid relid;
11170 Oid confrelid;
11171 char contype;
11172 bool conislocal;
11173
11174 tup = SearchSysCache1(CONSTROID, ObjectIdGetDatum(oldId));
11175 if (!HeapTupleIsValid(tup)) /* should not happen */
11176 elog(ERROR, "cache lookup failed for constraint %u", oldId);
11177 con = (Form_pg_constraint) GETSTRUCT(tup);
11178 if (OidIsValid(con->conrelid))
11179 relid = con->conrelid;
11180 else
11181 {
11182 /* must be a domain constraint */
11183 relid = get_typ_typrelid(getBaseType(con->contypid));
11184 if (!OidIsValid(relid))
11185 elog(ERROR, "could not identify relation associated with constraint %u", oldId);
11186 }
11187 confrelid = con->confrelid;
11188 contype = con->contype;
11189 conislocal = con->conislocal;
11190 ReleaseSysCache(tup);
11191
11192 ObjectAddressSet(obj, ConstraintRelationId, oldId);
11193 add_exact_object_address(&obj, objects);
11194
11195 /*
11196 * If the constraint is inherited (only), we don't want to inject a
11197 * new definition here; it'll get recreated when ATAddCheckConstraint
11198 * recurses from adding the parent table's constraint. But we had to
11199 * carry the info this far so that we can drop the constraint below.
11200 */
11201 if (!conislocal)
11202 continue;
11203
11204 /*
11205 * When rebuilding an FK constraint that references the table we're
11206 * modifying, we might not yet have any lock on the FK's table, so get
11207 * one now. We'll need AccessExclusiveLock for the DROP CONSTRAINT
11208 * step, so there's no value in asking for anything weaker.
11209 */
11210 if (relid != tab->relid && contype == CONSTRAINT_FOREIGN)
11211 LockRelationOid(relid, AccessExclusiveLock);
11212
11213 ATPostAlterTypeParse(oldId, relid, confrelid,
11214 (char *) lfirst(def_item),
11215 wqueue, lockmode, tab->rewrite);
11216 }
11217 forboth(oid_item, tab->changedIndexOids,
11218 def_item, tab->changedIndexDefs)
11219 {
11220 Oid oldId = lfirst_oid(oid_item);
11221 Oid relid;
11222
11223 relid = IndexGetRelation(oldId, false);
11224 ATPostAlterTypeParse(oldId, relid, InvalidOid,
11225 (char *) lfirst(def_item),
11226 wqueue, lockmode, tab->rewrite);
11227
11228 ObjectAddressSet(obj, RelationRelationId, oldId);
11229 add_exact_object_address(&obj, objects);
11230 }
11231
11232 /*
11233 * It should be okay to use DROP_RESTRICT here, since nothing else should
11234 * be depending on these objects.
11235 */
11236 performMultipleDeletions(objects, DROP_RESTRICT, PERFORM_DELETION_INTERNAL);
11237
11238 free_object_addresses(objects);
11239
11240 /*
11241 * The objects will get recreated during subsequent passes over the work
11242 * queue.
11243 */
11244}
11245
11246/*
11247 * Parse the previously-saved definition string for a constraint or index
11248 * against the newly-established column data type(s), and queue up the
11249 * resulting command parsetrees for execution.
11250 *
11251 * This might fail if, for example, you have a WHERE clause that uses an
11252 * operator that's not available for the new column type.
11253 */
11254static void
11255ATPostAlterTypeParse(Oid oldId, Oid oldRelId, Oid refRelId, char *cmd,
11256 List **wqueue, LOCKMODE lockmode, bool rewrite)
11257{
11258 List *raw_parsetree_list;
11259 List *querytree_list;
11260 ListCell *list_item;
11261 Relation rel;
11262
11263 /*
11264 * We expect that we will get only ALTER TABLE and CREATE INDEX
11265 * statements. Hence, there is no need to pass them through
11266 * parse_analyze() or the rewriter, but instead we need to pass them
11267 * through parse_utilcmd.c to make them ready for execution.
11268 */
11269 raw_parsetree_list = raw_parser(cmd);
11270 querytree_list = NIL;
11271 foreach(list_item, raw_parsetree_list)
11272 {
11273 RawStmt *rs = lfirst_node(RawStmt, list_item);
11274 Node *stmt = rs->stmt;
11275
11276 if (IsA(stmt, IndexStmt))
11277 querytree_list = lappend(querytree_list,
11278 transformIndexStmt(oldRelId,
11279 (IndexStmt *) stmt,
11280 cmd));
11281 else if (IsA(stmt, AlterTableStmt))
11282 querytree_list = list_concat(querytree_list,
11283 transformAlterTableStmt(oldRelId,
11284 (AlterTableStmt *) stmt,
11285 cmd));
11286 else
11287 querytree_list = lappend(querytree_list, stmt);
11288 }
11289
11290 /* Caller should already have acquired whatever lock we need. */
11291 rel = relation_open(oldRelId, NoLock);
11292
11293 /*
11294 * Attach each generated command to the proper place in the work queue.
11295 * Note this could result in creation of entirely new work-queue entries.
11296 *
11297 * Also note that we have to tweak the command subtypes, because it turns
11298 * out that re-creation of indexes and constraints has to act a bit
11299 * differently from initial creation.
11300 */
11301 foreach(list_item, querytree_list)
11302 {
11303 Node *stm = (Node *) lfirst(list_item);
11304 AlteredTableInfo *tab;
11305
11306 tab = ATGetQueueEntry(wqueue, rel);
11307
11308 if (IsA(stm, IndexStmt))
11309 {
11310 IndexStmt *stmt = (IndexStmt *) stm;
11311 AlterTableCmd *newcmd;
11312
11313 if (!rewrite)
11314 TryReuseIndex(oldId, stmt);
11315 stmt->reset_default_tblspc = true;
11316 /* keep the index's comment */
11317 stmt->idxcomment = GetComment(oldId, RelationRelationId, 0);
11318
11319 newcmd = makeNode(AlterTableCmd);
11320 newcmd->subtype = AT_ReAddIndex;
11321 newcmd->def = (Node *) stmt;
11322 tab->subcmds[AT_PASS_OLD_INDEX] =
11323 lappend(tab->subcmds[AT_PASS_OLD_INDEX], newcmd);
11324 }
11325 else if (IsA(stm, AlterTableStmt))
11326 {
11327 AlterTableStmt *stmt = (AlterTableStmt *) stm;
11328 ListCell *lcmd;
11329
11330 foreach(lcmd, stmt->cmds)
11331 {
11332 AlterTableCmd *cmd = castNode(AlterTableCmd, lfirst(lcmd));
11333
11334 if (cmd->subtype == AT_AddIndex)
11335 {
11336 IndexStmt *indstmt;
11337 Oid indoid;
11338
11339 indstmt = castNode(IndexStmt, cmd->def);
11340 indoid = get_constraint_index(oldId);
11341
11342 if (!rewrite)
11343 TryReuseIndex(indoid, indstmt);
11344 /* keep any comment on the index */
11345 indstmt->idxcomment = GetComment(indoid,
11346 RelationRelationId, 0);
11347 indstmt->reset_default_tblspc = true;
11348
11349 cmd->subtype = AT_ReAddIndex;
11350 tab->subcmds[AT_PASS_OLD_INDEX] =
11351 lappend(tab->subcmds[AT_PASS_OLD_INDEX], cmd);
11352
11353 /* recreate any comment on the constraint */
11354 RebuildConstraintComment(tab,
11355 AT_PASS_OLD_INDEX,
11356 oldId,
11357 rel,
11358 NIL,
11359 indstmt->idxname);
11360 }
11361 else if (cmd->subtype == AT_AddConstraint)
11362 {
11363 Constraint *con = castNode(Constraint, cmd->def);
11364
11365 con->old_pktable_oid = refRelId;
11366 /* rewriting neither side of a FK */
11367 if (con->contype == CONSTR_FOREIGN &&
11368 !rewrite && tab->rewrite == 0)
11369 TryReuseForeignKey(oldId, con);
11370 con->reset_default_tblspc = true;
11371 cmd->subtype = AT_ReAddConstraint;
11372 tab->subcmds[AT_PASS_OLD_CONSTR] =
11373 lappend(tab->subcmds[AT_PASS_OLD_CONSTR], cmd);
11374
11375 /* recreate any comment on the constraint */
11376 RebuildConstraintComment(tab,
11377 AT_PASS_OLD_CONSTR,
11378 oldId,
11379 rel,
11380 NIL,
11381 con->conname);
11382 }
11383 else if (cmd->subtype == AT_SetNotNull)
11384 {
11385 /*
11386 * The parser will create AT_SetNotNull subcommands for
11387 * columns of PRIMARY KEY indexes/constraints, but we need
11388 * not do anything with them here, because the columns'
11389 * NOT NULL marks will already have been propagated into
11390 * the new table definition.
11391 */
11392 }
11393 else
11394 elog(ERROR, "unexpected statement subtype: %d",
11395 (int) cmd->subtype);
11396 }
11397 }
11398 else if (IsA(stm, AlterDomainStmt))
11399 {
11400 AlterDomainStmt *stmt = (AlterDomainStmt *) stm;
11401
11402 if (stmt->subtype == 'C') /* ADD CONSTRAINT */
11403 {
11404 Constraint *con = castNode(Constraint, stmt->def);
11405 AlterTableCmd *cmd = makeNode(AlterTableCmd);
11406
11407 cmd->subtype = AT_ReAddDomainConstraint;
11408 cmd->def = (Node *) stmt;
11409 tab->subcmds[AT_PASS_OLD_CONSTR] =
11410 lappend(tab->subcmds[AT_PASS_OLD_CONSTR], cmd);
11411
11412 /* recreate any comment on the constraint */
11413 RebuildConstraintComment(tab,
11414 AT_PASS_OLD_CONSTR,
11415 oldId,
11416 NULL,
11417 stmt->typeName,
11418 con->conname);
11419 }
11420 else
11421 elog(ERROR, "unexpected statement subtype: %d",
11422 (int) stmt->subtype);
11423 }
11424 else
11425 elog(ERROR, "unexpected statement type: %d",
11426 (int) nodeTag(stm));
11427 }
11428
11429 relation_close(rel, NoLock);
11430}
11431
11432/*
11433 * Subroutine for ATPostAlterTypeParse() to recreate any existing comment
11434 * for a table or domain constraint that is being rebuilt.
11435 *
11436 * objid is the OID of the constraint.
11437 * Pass "rel" for a table constraint, or "domname" (domain's qualified name
11438 * as a string list) for a domain constraint.
11439 * (We could dig that info, as well as the conname, out of the pg_constraint
11440 * entry; but callers already have them so might as well pass them.)
11441 */
11442static void
11443RebuildConstraintComment(AlteredTableInfo *tab, int pass, Oid objid,
11444 Relation rel, List *domname,
11445 const char *conname)
11446{
11447 CommentStmt *cmd;
11448 char *comment_str;
11449 AlterTableCmd *newcmd;
11450
11451 /* Look for comment for object wanted, and leave if none */
11452 comment_str = GetComment(objid, ConstraintRelationId, 0);
11453 if (comment_str == NULL)
11454 return;
11455
11456 /* Build CommentStmt node, copying all input data for safety */
11457 cmd = makeNode(CommentStmt);
11458 if (rel)
11459 {
11460 cmd->objtype = OBJECT_TABCONSTRAINT;
11461 cmd->object = (Node *)
11462 list_make3(makeString(get_namespace_name(RelationGetNamespace(rel))),
11463 makeString(pstrdup(RelationGetRelationName(rel))),
11464 makeString(pstrdup(conname)));
11465 }
11466 else
11467 {
11468 cmd->objtype = OBJECT_DOMCONSTRAINT;
11469 cmd->object = (Node *)
11470 list_make2(makeTypeNameFromNameList(copyObject(domname)),
11471 makeString(pstrdup(conname)));
11472 }
11473 cmd->comment = comment_str;
11474
11475 /* Append it to list of commands */
11476 newcmd = makeNode(AlterTableCmd);
11477 newcmd->subtype = AT_ReAddComment;
11478 newcmd->def = (Node *) cmd;
11479 tab->subcmds[pass] = lappend(tab->subcmds[pass], newcmd);
11480}
11481
11482/*
11483 * Subroutine for ATPostAlterTypeParse(). Calls out to CheckIndexCompatible()
11484 * for the real analysis, then mutates the IndexStmt based on that verdict.
11485 */
11486static void
11487TryReuseIndex(Oid oldId, IndexStmt *stmt)
11488{
11489 if (CheckIndexCompatible(oldId,
11490 stmt->accessMethod,
11491 stmt->indexParams,
11492 stmt->excludeOpNames))
11493 {
11494 Relation irel = index_open(oldId, NoLock);
11495
11496 /* If it's a partitioned index, there is no storage to share. */
11497 if (irel->rd_rel->relkind != RELKIND_PARTITIONED_INDEX)
11498 stmt->oldNode = irel->rd_node.relNode;
11499 index_close(irel, NoLock);
11500 }
11501}
11502
11503/*
11504 * Subroutine for ATPostAlterTypeParse().
11505 *
11506 * Stash the old P-F equality operator into the Constraint node, for possible
11507 * use by ATAddForeignKeyConstraint() in determining whether revalidation of
11508 * this constraint can be skipped.
11509 */
11510static void
11511TryReuseForeignKey(Oid oldId, Constraint *con)
11512{
11513 HeapTuple tup;
11514 Datum adatum;
11515 bool isNull;
11516 ArrayType *arr;
11517 Oid *rawarr;
11518 int numkeys;
11519 int i;
11520
11521 Assert(con->contype == CONSTR_FOREIGN);
11522 Assert(con->old_conpfeqop == NIL); /* already prepared this node */
11523
11524 tup = SearchSysCache1(CONSTROID, ObjectIdGetDatum(oldId));
11525 if (!HeapTupleIsValid(tup)) /* should not happen */
11526 elog(ERROR, "cache lookup failed for constraint %u", oldId);
11527
11528 adatum = SysCacheGetAttr(CONSTROID, tup,
11529 Anum_pg_constraint_conpfeqop, &isNull);
11530 if (isNull)
11531 elog(ERROR, "null conpfeqop for constraint %u", oldId);
11532 arr = DatumGetArrayTypeP(adatum); /* ensure not toasted */
11533 numkeys = ARR_DIMS(arr)[0];
11534 /* test follows the one in ri_FetchConstraintInfo() */
11535 if (ARR_NDIM(arr) != 1 ||
11536 ARR_HASNULL(arr) ||
11537 ARR_ELEMTYPE(arr) != OIDOID)
11538 elog(ERROR, "conpfeqop is not a 1-D Oid array");
11539 rawarr = (Oid *) ARR_DATA_PTR(arr);
11540
11541 /* stash a List of the operator Oids in our Constraint node */
11542 for (i = 0; i < numkeys; i++)
11543 con->old_conpfeqop = lappend_oid(con->old_conpfeqop, rawarr[i]);
11544
11545 ReleaseSysCache(tup);
11546}
11547
11548/*
11549 * ALTER COLUMN .. OPTIONS ( ... )
11550 *
11551 * Returns the address of the modified column
11552 */
11553static ObjectAddress
11554ATExecAlterColumnGenericOptions(Relation rel,
11555 const char *colName,
11556 List *options,
11557 LOCKMODE lockmode)
11558{
11559 Relation ftrel;
11560 Relation attrel;
11561 ForeignServer *server;
11562 ForeignDataWrapper *fdw;
11563 HeapTuple tuple;
11564 HeapTuple newtuple;
11565 bool isnull;
11566 Datum repl_val[Natts_pg_attribute];
11567 bool repl_null[Natts_pg_attribute];
11568 bool repl_repl[Natts_pg_attribute];
11569 Datum datum;
11570 Form_pg_foreign_table fttableform;
11571 Form_pg_attribute atttableform;
11572 AttrNumber attnum;
11573 ObjectAddress address;
11574
11575 if (options == NIL)
11576 return InvalidObjectAddress;
11577
11578 /* First, determine FDW validator associated to the foreign table. */
11579 ftrel = table_open(ForeignTableRelationId, AccessShareLock);
11580 tuple = SearchSysCache1(FOREIGNTABLEREL, rel->rd_id);
11581 if (!HeapTupleIsValid(tuple))
11582 ereport(ERROR,
11583 (errcode(ERRCODE_UNDEFINED_OBJECT),
11584 errmsg("foreign table \"%s\" does not exist",
11585 RelationGetRelationName(rel))));
11586 fttableform = (Form_pg_foreign_table) GETSTRUCT(tuple);
11587 server = GetForeignServer(fttableform->ftserver);
11588 fdw = GetForeignDataWrapper(server->fdwid);
11589
11590 table_close(ftrel, AccessShareLock);
11591 ReleaseSysCache(tuple);
11592
11593 attrel = table_open(AttributeRelationId, RowExclusiveLock);
11594 tuple = SearchSysCacheAttName(RelationGetRelid(rel), colName);
11595 if (!HeapTupleIsValid(tuple))
11596 ereport(ERROR,
11597 (errcode(ERRCODE_UNDEFINED_COLUMN),
11598 errmsg("column \"%s\" of relation \"%s\" does not exist",
11599 colName, RelationGetRelationName(rel))));
11600
11601 /* Prevent them from altering a system attribute */
11602 atttableform = (Form_pg_attribute) GETSTRUCT(tuple);
11603 attnum = atttableform->attnum;
11604 if (attnum <= 0)
11605 ereport(ERROR,
11606 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
11607 errmsg("cannot alter system column \"%s\"", colName)));
11608
11609
11610 /* Initialize buffers for new tuple values */
11611 memset(repl_val, 0, sizeof(repl_val));
11612 memset(repl_null, false, sizeof(repl_null));
11613 memset(repl_repl, false, sizeof(repl_repl));
11614
11615 /* Extract the current options */
11616 datum = SysCacheGetAttr(ATTNAME,
11617 tuple,
11618 Anum_pg_attribute_attfdwoptions,
11619 &isnull);
11620 if (isnull)
11621 datum = PointerGetDatum(NULL);
11622
11623 /* Transform the options */
11624 datum = transformGenericOptions(AttributeRelationId,
11625 datum,
11626 options,
11627 fdw->fdwvalidator);
11628
11629 if (PointerIsValid(DatumGetPointer(datum)))
11630 repl_val[Anum_pg_attribute_attfdwoptions - 1] = datum;
11631 else
11632 repl_null[Anum_pg_attribute_attfdwoptions - 1] = true;
11633
11634 repl_repl[Anum_pg_attribute_attfdwoptions - 1] = true;
11635
11636 /* Everything looks good - update the tuple */
11637
11638 newtuple = heap_modify_tuple(tuple, RelationGetDescr(attrel),
11639 repl_val, repl_null, repl_repl);
11640
11641 CatalogTupleUpdate(attrel, &newtuple->t_self, newtuple);
11642
11643 InvokeObjectPostAlterHook(RelationRelationId,
11644 RelationGetRelid(rel),
11645 atttableform->attnum);
11646 ObjectAddressSubSet(address, RelationRelationId,
11647 RelationGetRelid(rel), attnum);
11648
11649 ReleaseSysCache(tuple);
11650
11651 table_close(attrel, RowExclusiveLock);
11652
11653 heap_freetuple(newtuple);
11654
11655 return address;
11656}
11657
11658/*
11659 * ALTER TABLE OWNER
11660 *
11661 * recursing is true if we are recursing from a table to its indexes,
11662 * sequences, or toast table. We don't allow the ownership of those things to
11663 * be changed separately from the parent table. Also, we can skip permission
11664 * checks (this is necessary not just an optimization, else we'd fail to
11665 * handle toast tables properly).
11666 *
11667 * recursing is also true if ALTER TYPE OWNER is calling us to fix up a
11668 * free-standing composite type.
11669 */
11670void
11671ATExecChangeOwner(Oid relationOid, Oid newOwnerId, bool recursing, LOCKMODE lockmode)
11672{
11673 Relation target_rel;
11674 Relation class_rel;
11675 HeapTuple tuple;
11676 Form_pg_class tuple_class;
11677
11678 /*
11679 * Get exclusive lock till end of transaction on the target table. Use
11680 * relation_open so that we can work on indexes and sequences.
11681 */
11682 target_rel = relation_open(relationOid, lockmode);
11683
11684 /* Get its pg_class tuple, too */
11685 class_rel = table_open(RelationRelationId, RowExclusiveLock);
11686
11687 tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relationOid));
11688 if (!HeapTupleIsValid(tuple))
11689 elog(ERROR, "cache lookup failed for relation %u", relationOid);
11690 tuple_class = (Form_pg_class) GETSTRUCT(tuple);
11691
11692 /* Can we change the ownership of this tuple? */
11693 switch (tuple_class->relkind)
11694 {
11695 case RELKIND_RELATION:
11696 case RELKIND_VIEW:
11697 case RELKIND_MATVIEW:
11698 case RELKIND_FOREIGN_TABLE:
11699 case RELKIND_PARTITIONED_TABLE:
11700 /* ok to change owner */
11701 break;
11702 case RELKIND_INDEX:
11703 if (!recursing)
11704 {
11705 /*
11706 * Because ALTER INDEX OWNER used to be allowed, and in fact
11707 * is generated by old versions of pg_dump, we give a warning
11708 * and do nothing rather than erroring out. Also, to avoid
11709 * unnecessary chatter while restoring those old dumps, say
11710 * nothing at all if the command would be a no-op anyway.
11711 */
11712 if (tuple_class->relowner != newOwnerId)
11713 ereport(WARNING,
11714 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
11715 errmsg("cannot change owner of index \"%s\"",
11716 NameStr(tuple_class->relname)),
11717 errhint("Change the ownership of the index's table, instead.")));
11718 /* quick hack to exit via the no-op path */
11719 newOwnerId = tuple_class->relowner;
11720 }
11721 break;
11722 case RELKIND_PARTITIONED_INDEX:
11723 if (recursing)
11724 break;
11725 ereport(ERROR,
11726 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
11727 errmsg("cannot change owner of index \"%s\"",
11728 NameStr(tuple_class->relname)),
11729 errhint("Change the ownership of the index's table, instead.")));
11730 break;
11731 case RELKIND_SEQUENCE:
11732 if (!recursing &&
11733 tuple_class->relowner != newOwnerId)
11734 {
11735 /* if it's an owned sequence, disallow changing it by itself */
11736 Oid tableId;
11737 int32 colId;
11738
11739 if (sequenceIsOwned(relationOid, DEPENDENCY_AUTO, &tableId, &colId) ||
11740 sequenceIsOwned(relationOid, DEPENDENCY_INTERNAL, &tableId, &colId))
11741 ereport(ERROR,
11742 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
11743 errmsg("cannot change owner of sequence \"%s\"",
11744 NameStr(tuple_class->relname)),
11745 errdetail("Sequence \"%s\" is linked to table \"%s\".",
11746 NameStr(tuple_class->relname),
11747 get_rel_name(tableId))));
11748 }
11749 break;
11750 case RELKIND_COMPOSITE_TYPE:
11751 if (recursing)
11752 break;
11753 ereport(ERROR,
11754 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
11755 errmsg("\"%s\" is a composite type",
11756 NameStr(tuple_class->relname)),
11757 errhint("Use ALTER TYPE instead.")));
11758 break;
11759 case RELKIND_TOASTVALUE:
11760 if (recursing)
11761 break;
11762 /* FALL THRU */
11763 default:
11764 ereport(ERROR,
11765 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
11766 errmsg("\"%s\" is not a table, view, sequence, or foreign table",
11767 NameStr(tuple_class->relname))));
11768 }
11769
11770 /*
11771 * If the new owner is the same as the existing owner, consider the
11772 * command to have succeeded. This is for dump restoration purposes.
11773 */
11774 if (tuple_class->relowner != newOwnerId)
11775 {
11776 Datum repl_val[Natts_pg_class];
11777 bool repl_null[Natts_pg_class];
11778 bool repl_repl[Natts_pg_class];
11779 Acl *newAcl;
11780 Datum aclDatum;
11781 bool isNull;
11782 HeapTuple newtuple;
11783
11784 /* skip permission checks when recursing to index or toast table */
11785 if (!recursing)
11786 {
11787 /* Superusers can always do it */
11788 if (!superuser())
11789 {
11790 Oid namespaceOid = tuple_class->relnamespace;
11791 AclResult aclresult;
11792
11793 /* Otherwise, must be owner of the existing object */
11794 if (!pg_class_ownercheck(relationOid, GetUserId()))
11795 aclcheck_error(ACLCHECK_NOT_OWNER, get_relkind_objtype(get_rel_relkind(relationOid)),
11796 RelationGetRelationName(target_rel));
11797
11798 /* Must be able to become new owner */
11799 check_is_member_of_role(GetUserId(), newOwnerId);
11800
11801 /* New owner must have CREATE privilege on namespace */
11802 aclresult = pg_namespace_aclcheck(namespaceOid, newOwnerId,
11803 ACL_CREATE);
11804 if (aclresult != ACLCHECK_OK)
11805 aclcheck_error(aclresult, OBJECT_SCHEMA,
11806 get_namespace_name(namespaceOid));
11807 }
11808 }
11809
11810 memset(repl_null, false, sizeof(repl_null));
11811 memset(repl_repl, false, sizeof(repl_repl));
11812
11813 repl_repl[Anum_pg_class_relowner - 1] = true;
11814 repl_val[Anum_pg_class_relowner - 1] = ObjectIdGetDatum(newOwnerId);
11815
11816 /*
11817 * Determine the modified ACL for the new owner. This is only
11818 * necessary when the ACL is non-null.
11819 */
11820 aclDatum = SysCacheGetAttr(RELOID, tuple,
11821 Anum_pg_class_relacl,
11822 &isNull);
11823 if (!isNull)
11824 {
11825 newAcl = aclnewowner(DatumGetAclP(aclDatum),
11826 tuple_class->relowner, newOwnerId);
11827 repl_repl[Anum_pg_class_relacl - 1] = true;
11828 repl_val[Anum_pg_class_relacl - 1] = PointerGetDatum(newAcl);
11829 }
11830
11831 newtuple = heap_modify_tuple(tuple, RelationGetDescr(class_rel), repl_val, repl_null, repl_repl);
11832
11833 CatalogTupleUpdate(class_rel, &newtuple->t_self, newtuple);
11834
11835 heap_freetuple(newtuple);
11836
11837 /*
11838 * We must similarly update any per-column ACLs to reflect the new
11839 * owner; for neatness reasons that's split out as a subroutine.
11840 */
11841 change_owner_fix_column_acls(relationOid,
11842 tuple_class->relowner,
11843 newOwnerId);
11844
11845 /*
11846 * Update owner dependency reference, if any. A composite type has
11847 * none, because it's tracked for the pg_type entry instead of here;
11848 * indexes and TOAST tables don't have their own entries either.
11849 */
11850 if (tuple_class->relkind != RELKIND_COMPOSITE_TYPE &&
11851 tuple_class->relkind != RELKIND_INDEX &&
11852 tuple_class->relkind != RELKIND_PARTITIONED_INDEX &&
11853 tuple_class->relkind != RELKIND_TOASTVALUE)
11854 changeDependencyOnOwner(RelationRelationId, relationOid,
11855 newOwnerId);
11856
11857 /*
11858 * Also change the ownership of the table's row type, if it has one
11859 */
11860 if (tuple_class->relkind != RELKIND_INDEX &&
11861 tuple_class->relkind != RELKIND_PARTITIONED_INDEX)
11862 AlterTypeOwnerInternal(tuple_class->reltype, newOwnerId);
11863
11864 /*
11865 * If we are operating on a table or materialized view, also change
11866 * the ownership of any indexes and sequences that belong to the
11867 * relation, as well as its toast table (if it has one).
11868 */
11869 if (tuple_class->relkind == RELKIND_RELATION ||
11870 tuple_class->relkind == RELKIND_PARTITIONED_TABLE ||
11871 tuple_class->relkind == RELKIND_MATVIEW ||
11872 tuple_class->relkind == RELKIND_TOASTVALUE)
11873 {
11874 List *index_oid_list;
11875 ListCell *i;
11876
11877 /* Find all the indexes belonging to this relation */
11878 index_oid_list = RelationGetIndexList(target_rel);
11879
11880 /* For each index, recursively change its ownership */
11881 foreach(i, index_oid_list)
11882 ATExecChangeOwner(lfirst_oid(i), newOwnerId, true, lockmode);
11883
11884 list_free(index_oid_list);
11885 }
11886
11887 /* If it has a toast table, recurse to change its ownership */
11888 if (tuple_class->reltoastrelid != InvalidOid)
11889 ATExecChangeOwner(tuple_class->reltoastrelid, newOwnerId,
11890 true, lockmode);
11891
11892 /* If it has dependent sequences, recurse to change them too */
11893 change_owner_recurse_to_sequences(relationOid, newOwnerId, lockmode);
11894 }
11895
11896 InvokeObjectPostAlterHook(RelationRelationId, relationOid, 0);
11897
11898 ReleaseSysCache(tuple);
11899 table_close(class_rel, RowExclusiveLock);
11900 relation_close(target_rel, NoLock);
11901}
11902
11903/*
11904 * change_owner_fix_column_acls
11905 *
11906 * Helper function for ATExecChangeOwner. Scan the columns of the table
11907 * and fix any non-null column ACLs to reflect the new owner.
11908 */
11909static void
11910change_owner_fix_column_acls(Oid relationOid, Oid oldOwnerId, Oid newOwnerId)
11911{
11912 Relation attRelation;
11913 SysScanDesc scan;
11914 ScanKeyData key[1];
11915 HeapTuple attributeTuple;
11916
11917 attRelation = table_open(AttributeRelationId, RowExclusiveLock);
11918 ScanKeyInit(&key[0],
11919 Anum_pg_attribute_attrelid,
11920 BTEqualStrategyNumber, F_OIDEQ,
11921 ObjectIdGetDatum(relationOid));
11922 scan = systable_beginscan(attRelation, AttributeRelidNumIndexId,
11923 true, NULL, 1, key);
11924 while (HeapTupleIsValid(attributeTuple = systable_getnext(scan)))
11925 {
11926 Form_pg_attribute att = (Form_pg_attribute) GETSTRUCT(attributeTuple);
11927 Datum repl_val[Natts_pg_attribute];
11928 bool repl_null[Natts_pg_attribute];
11929 bool repl_repl[Natts_pg_attribute];
11930 Acl *newAcl;
11931 Datum aclDatum;
11932 bool isNull;
11933 HeapTuple newtuple;
11934
11935 /* Ignore dropped columns */
11936 if (att->attisdropped)
11937 continue;
11938
11939 aclDatum = heap_getattr(attributeTuple,
11940 Anum_pg_attribute_attacl,
11941 RelationGetDescr(attRelation),
11942 &isNull);
11943 /* Null ACLs do not require changes */
11944 if (isNull)
11945 continue;
11946
11947 memset(repl_null, false, sizeof(repl_null));
11948 memset(repl_repl, false, sizeof(repl_repl));
11949
11950 newAcl = aclnewowner(DatumGetAclP(aclDatum),
11951 oldOwnerId, newOwnerId);
11952 repl_repl[Anum_pg_attribute_attacl - 1] = true;
11953 repl_val[Anum_pg_attribute_attacl - 1] = PointerGetDatum(newAcl);
11954
11955 newtuple = heap_modify_tuple(attributeTuple,
11956 RelationGetDescr(attRelation),
11957 repl_val, repl_null, repl_repl);
11958
11959 CatalogTupleUpdate(attRelation, &newtuple->t_self, newtuple);
11960
11961 heap_freetuple(newtuple);
11962 }
11963 systable_endscan(scan);
11964 table_close(attRelation, RowExclusiveLock);
11965}
11966
11967/*
11968 * change_owner_recurse_to_sequences
11969 *
11970 * Helper function for ATExecChangeOwner. Examines pg_depend searching
11971 * for sequences that are dependent on serial columns, and changes their
11972 * ownership.
11973 */
11974static void
11975change_owner_recurse_to_sequences(Oid relationOid, Oid newOwnerId, LOCKMODE lockmode)
11976{
11977 Relation depRel;
11978 SysScanDesc scan;
11979 ScanKeyData key[2];
11980 HeapTuple tup;
11981
11982 /*
11983 * SERIAL sequences are those having an auto dependency on one of the
11984 * table's columns (we don't care *which* column, exactly).
11985 */
11986 depRel = table_open(DependRelationId, AccessShareLock);
11987
11988 ScanKeyInit(&key[0],
11989 Anum_pg_depend_refclassid,
11990 BTEqualStrategyNumber, F_OIDEQ,
11991 ObjectIdGetDatum(RelationRelationId));
11992 ScanKeyInit(&key[1],
11993 Anum_pg_depend_refobjid,
11994 BTEqualStrategyNumber, F_OIDEQ,
11995 ObjectIdGetDatum(relationOid));
11996 /* we leave refobjsubid unspecified */
11997
11998 scan = systable_beginscan(depRel, DependReferenceIndexId, true,
11999 NULL, 2, key);
12000
12001 while (HeapTupleIsValid(tup = systable_getnext(scan)))
12002 {
12003 Form_pg_depend depForm = (Form_pg_depend) GETSTRUCT(tup);
12004 Relation seqRel;
12005
12006 /* skip dependencies other than auto dependencies on columns */
12007 if (depForm->refobjsubid == 0 ||
12008 depForm->classid != RelationRelationId ||
12009 depForm->objsubid != 0 ||
12010 !(depForm->deptype == DEPENDENCY_AUTO || depForm->deptype == DEPENDENCY_INTERNAL))
12011 continue;
12012
12013 /* Use relation_open just in case it's an index */
12014 seqRel = relation_open(depForm->objid, lockmode);
12015
12016 /* skip non-sequence relations */
12017 if (RelationGetForm(seqRel)->relkind != RELKIND_SEQUENCE)
12018 {
12019 /* No need to keep the lock */
12020 relation_close(seqRel, lockmode);
12021 continue;
12022 }
12023
12024 /* We don't need to close the sequence while we alter it. */
12025 ATExecChangeOwner(depForm->objid, newOwnerId, true, lockmode);
12026
12027 /* Now we can close it. Keep the lock till end of transaction. */
12028 relation_close(seqRel, NoLock);
12029 }
12030
12031 systable_endscan(scan);
12032
12033 relation_close(depRel, AccessShareLock);
12034}
12035
12036/*
12037 * ALTER TABLE CLUSTER ON
12038 *
12039 * The only thing we have to do is to change the indisclustered bits.
12040 *
12041 * Return the address of the new clustering index.
12042 */
12043static ObjectAddress
12044ATExecClusterOn(Relation rel, const char *indexName, LOCKMODE lockmode)
12045{
12046 Oid indexOid;
12047 ObjectAddress address;
12048
12049 indexOid = get_relname_relid(indexName, rel->rd_rel->relnamespace);
12050
12051 if (!OidIsValid(indexOid))
12052 ereport(ERROR,
12053 (errcode(ERRCODE_UNDEFINED_OBJECT),
12054 errmsg("index \"%s\" for table \"%s\" does not exist",
12055 indexName, RelationGetRelationName(rel))));
12056
12057 /* Check index is valid to cluster on */
12058 check_index_is_clusterable(rel, indexOid, false, lockmode);
12059
12060 /* And do the work */
12061 mark_index_clustered(rel, indexOid, false);
12062
12063 ObjectAddressSet(address,
12064 RelationRelationId, indexOid);
12065
12066 return address;
12067}
12068
12069/*
12070 * ALTER TABLE SET WITHOUT CLUSTER
12071 *
12072 * We have to find any indexes on the table that have indisclustered bit
12073 * set and turn it off.
12074 */
12075static void
12076ATExecDropCluster(Relation rel, LOCKMODE lockmode)
12077{
12078 mark_index_clustered(rel, InvalidOid, false);
12079}
12080
12081/*
12082 * ALTER TABLE SET TABLESPACE
12083 */
12084static void
12085ATPrepSetTableSpace(AlteredTableInfo *tab, Relation rel, const char *tablespacename, LOCKMODE lockmode)
12086{
12087 Oid tablespaceId;
12088
12089 /* Check that the tablespace exists */
12090 tablespaceId = get_tablespace_oid(tablespacename, false);
12091
12092 /* Check permissions except when moving to database's default */
12093 if (OidIsValid(tablespaceId) && tablespaceId != MyDatabaseTableSpace)
12094 {
12095 AclResult aclresult;
12096
12097 aclresult = pg_tablespace_aclcheck(tablespaceId, GetUserId(), ACL_CREATE);
12098 if (aclresult != ACLCHECK_OK)
12099 aclcheck_error(aclresult, OBJECT_TABLESPACE, tablespacename);
12100 }
12101
12102 /* Save info for Phase 3 to do the real work */
12103 if (OidIsValid(tab->newTableSpace))
12104 ereport(ERROR,
12105 (errcode(ERRCODE_SYNTAX_ERROR),
12106 errmsg("cannot have multiple SET TABLESPACE subcommands")));
12107
12108 tab->newTableSpace = tablespaceId;
12109}
12110
12111/*
12112 * Set, reset, or replace reloptions.
12113 */
12114static void
12115ATExecSetRelOptions(Relation rel, List *defList, AlterTableType operation,
12116 LOCKMODE lockmode)
12117{
12118 Oid relid;
12119 Relation pgclass;
12120 HeapTuple tuple;
12121 HeapTuple newtuple;
12122 Datum datum;
12123 bool isnull;
12124 Datum newOptions;
12125 Datum repl_val[Natts_pg_class];
12126 bool repl_null[Natts_pg_class];
12127 bool repl_repl[Natts_pg_class];
12128 static char *validnsps[] = HEAP_RELOPT_NAMESPACES;
12129
12130 if (defList == NIL && operation != AT_ReplaceRelOptions)
12131 return; /* nothing to do */
12132
12133 pgclass = table_open(RelationRelationId, RowExclusiveLock);
12134
12135 /* Fetch heap tuple */
12136 relid = RelationGetRelid(rel);
12137 tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
12138 if (!HeapTupleIsValid(tuple))
12139 elog(ERROR, "cache lookup failed for relation %u", relid);
12140
12141 if (operation == AT_ReplaceRelOptions)
12142 {
12143 /*
12144 * If we're supposed to replace the reloptions list, we just pretend
12145 * there were none before.
12146 */
12147 datum = (Datum) 0;
12148 isnull = true;
12149 }
12150 else
12151 {
12152 /* Get the old reloptions */
12153 datum = SysCacheGetAttr(RELOID, tuple, Anum_pg_class_reloptions,
12154 &isnull);
12155 }
12156
12157 /* Generate new proposed reloptions (text array) */
12158 newOptions = transformRelOptions(isnull ? (Datum) 0 : datum,
12159 defList, NULL, validnsps, false,
12160 operation == AT_ResetRelOptions);
12161
12162 /* Validate */
12163 switch (rel->rd_rel->relkind)
12164 {
12165 case RELKIND_RELATION:
12166 case RELKIND_TOASTVALUE:
12167 case RELKIND_MATVIEW:
12168 case RELKIND_PARTITIONED_TABLE:
12169 (void) heap_reloptions(rel->rd_rel->relkind, newOptions, true);
12170 break;
12171 case RELKIND_VIEW:
12172 (void) view_reloptions(newOptions, true);
12173 break;
12174 case RELKIND_INDEX:
12175 case RELKIND_PARTITIONED_INDEX:
12176 (void) index_reloptions(rel->rd_indam->amoptions, newOptions, true);
12177 break;
12178 default:
12179 ereport(ERROR,
12180 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
12181 errmsg("\"%s\" is not a table, view, materialized view, index, or TOAST table",
12182 RelationGetRelationName(rel))));
12183 break;
12184 }
12185
12186 /* Special-case validation of view options */
12187 if (rel->rd_rel->relkind == RELKIND_VIEW)
12188 {
12189 Query *view_query = get_view_query(rel);
12190 List *view_options = untransformRelOptions(newOptions);
12191 ListCell *cell;
12192 bool check_option = false;
12193
12194 foreach(cell, view_options)
12195 {
12196 DefElem *defel = (DefElem *) lfirst(cell);
12197
12198 if (strcmp(defel->defname, "check_option") == 0)
12199 check_option = true;
12200 }
12201
12202 /*
12203 * If the check option is specified, look to see if the view is
12204 * actually auto-updatable or not.
12205 */
12206 if (check_option)
12207 {
12208 const char *view_updatable_error =
12209 view_query_is_auto_updatable(view_query, true);
12210
12211 if (view_updatable_error)
12212 ereport(ERROR,
12213 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
12214 errmsg("WITH CHECK OPTION is supported only on automatically updatable views"),
12215 errhint("%s", _(view_updatable_error))));
12216 }
12217 }
12218
12219 /*
12220 * All we need do here is update the pg_class row; the new options will be
12221 * propagated into relcaches during post-commit cache inval.
12222 */
12223 memset(repl_val, 0, sizeof(repl_val));
12224 memset(repl_null, false, sizeof(repl_null));
12225 memset(repl_repl, false, sizeof(repl_repl));
12226
12227 if (newOptions != (Datum) 0)
12228 repl_val[Anum_pg_class_reloptions - 1] = newOptions;
12229 else
12230 repl_null[Anum_pg_class_reloptions - 1] = true;
12231
12232 repl_repl[Anum_pg_class_reloptions - 1] = true;
12233
12234 newtuple = heap_modify_tuple(tuple, RelationGetDescr(pgclass),
12235 repl_val, repl_null, repl_repl);
12236
12237 CatalogTupleUpdate(pgclass, &newtuple->t_self, newtuple);
12238
12239 InvokeObjectPostAlterHook(RelationRelationId, RelationGetRelid(rel), 0);
12240
12241 heap_freetuple(newtuple);
12242
12243 ReleaseSysCache(tuple);
12244
12245 /* repeat the whole exercise for the toast table, if there's one */
12246 if (OidIsValid(rel->rd_rel->reltoastrelid))
12247 {
12248 Relation toastrel;
12249 Oid toastid = rel->rd_rel->reltoastrelid;
12250
12251 toastrel = table_open(toastid, lockmode);
12252
12253 /* Fetch heap tuple */
12254 tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(toastid));
12255 if (!HeapTupleIsValid(tuple))
12256 elog(ERROR, "cache lookup failed for relation %u", toastid);
12257
12258 if (operation == AT_ReplaceRelOptions)
12259 {
12260 /*
12261 * If we're supposed to replace the reloptions list, we just
12262 * pretend there were none before.
12263 */
12264 datum = (Datum) 0;
12265 isnull = true;
12266 }
12267 else
12268 {
12269 /* Get the old reloptions */
12270 datum = SysCacheGetAttr(RELOID, tuple, Anum_pg_class_reloptions,
12271 &isnull);
12272 }
12273
12274 newOptions = transformRelOptions(isnull ? (Datum) 0 : datum,
12275 defList, "toast", validnsps, false,
12276 operation == AT_ResetRelOptions);
12277
12278 (void) heap_reloptions(RELKIND_TOASTVALUE, newOptions, true);
12279
12280 memset(repl_val, 0, sizeof(repl_val));
12281 memset(repl_null, false, sizeof(repl_null));
12282 memset(repl_repl, false, sizeof(repl_repl));
12283
12284 if (newOptions != (Datum) 0)
12285 repl_val[Anum_pg_class_reloptions - 1] = newOptions;
12286 else
12287 repl_null[Anum_pg_class_reloptions - 1] = true;
12288
12289 repl_repl[Anum_pg_class_reloptions - 1] = true;
12290
12291 newtuple = heap_modify_tuple(tuple, RelationGetDescr(pgclass),
12292 repl_val, repl_null, repl_repl);
12293
12294 CatalogTupleUpdate(pgclass, &newtuple->t_self, newtuple);
12295
12296 InvokeObjectPostAlterHookArg(RelationRelationId,
12297 RelationGetRelid(toastrel), 0,
12298 InvalidOid, true);
12299
12300 heap_freetuple(newtuple);
12301
12302 ReleaseSysCache(tuple);
12303
12304 table_close(toastrel, NoLock);
12305 }
12306
12307 table_close(pgclass, RowExclusiveLock);
12308}
12309
12310/*
12311 * Execute ALTER TABLE SET TABLESPACE for cases where there is no tuple
12312 * rewriting to be done, so we just want to copy the data as fast as possible.
12313 */
12314static void
12315ATExecSetTableSpace(Oid tableOid, Oid newTableSpace, LOCKMODE lockmode)
12316{
12317 Relation rel;
12318 Oid oldTableSpace;
12319 Oid reltoastrelid;
12320 Oid newrelfilenode;
12321 RelFileNode newrnode;
12322 Relation pg_class;
12323 HeapTuple tuple;
12324 Form_pg_class rd_rel;
12325 List *reltoastidxids = NIL;
12326 ListCell *lc;
12327
12328 /*
12329 * Need lock here in case we are recursing to toast table or index
12330 */
12331 rel = relation_open(tableOid, lockmode);
12332
12333 /*
12334 * No work if no change in tablespace.
12335 */
12336 oldTableSpace = rel->rd_rel->reltablespace;
12337 if (newTableSpace == oldTableSpace ||
12338 (newTableSpace == MyDatabaseTableSpace && oldTableSpace == 0))
12339 {
12340 InvokeObjectPostAlterHook(RelationRelationId,
12341 RelationGetRelid(rel), 0);
12342
12343 relation_close(rel, NoLock);
12344 return;
12345 }
12346
12347 /*
12348 * We cannot support moving mapped relations into different tablespaces.
12349 * (In particular this eliminates all shared catalogs.)
12350 */
12351 if (RelationIsMapped(rel))
12352 ereport(ERROR,
12353 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
12354 errmsg("cannot move system relation \"%s\"",
12355 RelationGetRelationName(rel))));
12356
12357 /* Can't move a non-shared relation into pg_global */
12358 if (newTableSpace == GLOBALTABLESPACE_OID)
12359 ereport(ERROR,
12360 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
12361 errmsg("only shared relations can be placed in pg_global tablespace")));
12362
12363 /*
12364 * Don't allow moving temp tables of other backends ... their local buffer
12365 * manager is not going to cope.
12366 */
12367 if (RELATION_IS_OTHER_TEMP(rel))
12368 ereport(ERROR,
12369 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
12370 errmsg("cannot move temporary tables of other sessions")));
12371
12372 reltoastrelid = rel->rd_rel->reltoastrelid;
12373 /* Fetch the list of indexes on toast relation if necessary */
12374 if (OidIsValid(reltoastrelid))
12375 {
12376 Relation toastRel = relation_open(reltoastrelid, lockmode);
12377
12378 reltoastidxids = RelationGetIndexList(toastRel);
12379 relation_close(toastRel, lockmode);
12380 }
12381
12382 /* Get a modifiable copy of the relation's pg_class row */
12383 pg_class = table_open(RelationRelationId, RowExclusiveLock);
12384
12385 tuple = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(tableOid));
12386 if (!HeapTupleIsValid(tuple))
12387 elog(ERROR, "cache lookup failed for relation %u", tableOid);
12388 rd_rel = (Form_pg_class) GETSTRUCT(tuple);
12389
12390 /*
12391 * Relfilenodes are not unique in databases across tablespaces, so we need
12392 * to allocate a new one in the new tablespace.
12393 */
12394 newrelfilenode = GetNewRelFileNode(newTableSpace, NULL,
12395 rel->rd_rel->relpersistence);
12396
12397 /* Open old and new relation */
12398 newrnode = rel->rd_node;
12399 newrnode.relNode = newrelfilenode;
12400 newrnode.spcNode = newTableSpace;
12401
12402 /* hand off to AM to actually create the new filenode and copy the data */
12403 if (rel->rd_rel->relkind == RELKIND_INDEX)
12404 {
12405 index_copy_data(rel, newrnode);
12406 }
12407 else
12408 {
12409 Assert(rel->rd_rel->relkind == RELKIND_RELATION ||
12410 rel->rd_rel->relkind == RELKIND_MATVIEW ||
12411 rel->rd_rel->relkind == RELKIND_TOASTVALUE);
12412 table_relation_copy_data(rel, &newrnode);
12413 }
12414
12415 /*
12416 * Update the pg_class row.
12417 *
12418 * NB: This wouldn't work if ATExecSetTableSpace() were allowed to be
12419 * executed on pg_class or its indexes (the above copy wouldn't contain
12420 * the updated pg_class entry), but that's forbidden above.
12421 */
12422 rd_rel->reltablespace = (newTableSpace == MyDatabaseTableSpace) ? InvalidOid : newTableSpace;
12423 rd_rel->relfilenode = newrelfilenode;
12424 CatalogTupleUpdate(pg_class, &tuple->t_self, tuple);
12425
12426 InvokeObjectPostAlterHook(RelationRelationId, RelationGetRelid(rel), 0);
12427
12428 heap_freetuple(tuple);
12429
12430 table_close(pg_class, RowExclusiveLock);
12431
12432 relation_close(rel, NoLock);
12433
12434 /* Make sure the reltablespace change is visible */
12435 CommandCounterIncrement();
12436
12437 /* Move associated toast relation and/or indexes, too */
12438 if (OidIsValid(reltoastrelid))
12439 ATExecSetTableSpace(reltoastrelid, newTableSpace, lockmode);
12440 foreach(lc, reltoastidxids)
12441 ATExecSetTableSpace(lfirst_oid(lc), newTableSpace, lockmode);
12442
12443 /* Clean up */
12444 list_free(reltoastidxids);
12445}
12446
12447/*
12448 * Special handling of ALTER TABLE SET TABLESPACE for relations with no
12449 * storage that have an interest in preserving tablespace.
12450 *
12451 * Since these have no storage the tablespace can be updated with a simple
12452 * metadata only operation to update the tablespace.
12453 */
12454static void
12455ATExecSetTableSpaceNoStorage(Relation rel, Oid newTableSpace)
12456{
12457 HeapTuple tuple;
12458 Oid oldTableSpace;
12459 Relation pg_class;
12460 Form_pg_class rd_rel;
12461 Oid reloid = RelationGetRelid(rel);
12462
12463 /*
12464 * Shouldn't be called on relations having storage; these are processed in
12465 * phase 3.
12466 */
12467 Assert(!RELKIND_HAS_STORAGE(rel->rd_rel->relkind));
12468
12469 /* Can't allow a non-shared relation in pg_global */
12470 if (newTableSpace == GLOBALTABLESPACE_OID)
12471 ereport(ERROR,
12472 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
12473 errmsg("only shared relations can be placed in pg_global tablespace")));
12474
12475 /*
12476 * No work if no change in tablespace.
12477 */
12478 oldTableSpace = rel->rd_rel->reltablespace;
12479 if (newTableSpace == oldTableSpace ||
12480 (newTableSpace == MyDatabaseTableSpace && oldTableSpace == 0))
12481 {
12482 InvokeObjectPostAlterHook(RelationRelationId, reloid, 0);
12483 return;
12484 }
12485
12486 /* Get a modifiable copy of the relation's pg_class row */
12487 pg_class = table_open(RelationRelationId, RowExclusiveLock);
12488
12489 tuple = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(reloid));
12490 if (!HeapTupleIsValid(tuple))
12491 elog(ERROR, "cache lookup failed for relation %u", reloid);
12492 rd_rel = (Form_pg_class) GETSTRUCT(tuple);
12493
12494 /* update the pg_class row */
12495 rd_rel->reltablespace = (newTableSpace == MyDatabaseTableSpace) ? InvalidOid : newTableSpace;
12496 CatalogTupleUpdate(pg_class, &tuple->t_self, tuple);
12497
12498 InvokeObjectPostAlterHook(RelationRelationId, reloid, 0);
12499
12500 heap_freetuple(tuple);
12501
12502 table_close(pg_class, RowExclusiveLock);
12503
12504 /* Make sure the reltablespace change is visible */
12505 CommandCounterIncrement();
12506}
12507
12508/*
12509 * Alter Table ALL ... SET TABLESPACE
12510 *
12511 * Allows a user to move all objects of some type in a given tablespace in the
12512 * current database to another tablespace. Objects can be chosen based on the
12513 * owner of the object also, to allow users to move only their objects.
12514 * The user must have CREATE rights on the new tablespace, as usual. The main
12515 * permissions handling is done by the lower-level table move function.
12516 *
12517 * All to-be-moved objects are locked first. If NOWAIT is specified and the
12518 * lock can't be acquired then we ereport(ERROR).
12519 */
12520Oid
12521AlterTableMoveAll(AlterTableMoveAllStmt *stmt)
12522{
12523 List *relations = NIL;
12524 ListCell *l;
12525 ScanKeyData key[1];
12526 Relation rel;
12527 TableScanDesc scan;
12528 HeapTuple tuple;
12529 Oid orig_tablespaceoid;
12530 Oid new_tablespaceoid;
12531 List *role_oids = roleSpecsToIds(stmt->roles);
12532
12533 /* Ensure we were not asked to move something we can't */
12534 if (stmt->objtype != OBJECT_TABLE && stmt->objtype != OBJECT_INDEX &&
12535 stmt->objtype != OBJECT_MATVIEW)
12536 ereport(ERROR,
12537 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
12538 errmsg("only tables, indexes, and materialized views exist in tablespaces")));
12539
12540 /* Get the orig and new tablespace OIDs */
12541 orig_tablespaceoid = get_tablespace_oid(stmt->orig_tablespacename, false);
12542 new_tablespaceoid = get_tablespace_oid(stmt->new_tablespacename, false);
12543
12544 /* Can't move shared relations in to or out of pg_global */
12545 /* This is also checked by ATExecSetTableSpace, but nice to stop earlier */
12546 if (orig_tablespaceoid == GLOBALTABLESPACE_OID ||
12547 new_tablespaceoid == GLOBALTABLESPACE_OID)
12548 ereport(ERROR,
12549 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
12550 errmsg("cannot move relations in to or out of pg_global tablespace")));
12551
12552 /*
12553 * Must have CREATE rights on the new tablespace, unless it is the
12554 * database default tablespace (which all users implicitly have CREATE
12555 * rights on).
12556 */
12557 if (OidIsValid(new_tablespaceoid) && new_tablespaceoid != MyDatabaseTableSpace)
12558 {
12559 AclResult aclresult;
12560
12561 aclresult = pg_tablespace_aclcheck(new_tablespaceoid, GetUserId(),
12562 ACL_CREATE);
12563 if (aclresult != ACLCHECK_OK)
12564 aclcheck_error(aclresult, OBJECT_TABLESPACE,
12565 get_tablespace_name(new_tablespaceoid));
12566 }
12567
12568 /*
12569 * Now that the checks are done, check if we should set either to
12570 * InvalidOid because it is our database's default tablespace.
12571 */
12572 if (orig_tablespaceoid == MyDatabaseTableSpace)
12573 orig_tablespaceoid = InvalidOid;
12574
12575 if (new_tablespaceoid == MyDatabaseTableSpace)
12576 new_tablespaceoid = InvalidOid;
12577
12578 /* no-op */
12579 if (orig_tablespaceoid == new_tablespaceoid)
12580 return new_tablespaceoid;
12581
12582 /*
12583 * Walk the list of objects in the tablespace and move them. This will
12584 * only find objects in our database, of course.
12585 */
12586 ScanKeyInit(&key[0],
12587 Anum_pg_class_reltablespace,
12588 BTEqualStrategyNumber, F_OIDEQ,
12589 ObjectIdGetDatum(orig_tablespaceoid));
12590
12591 rel = table_open(RelationRelationId, AccessShareLock);
12592 scan = table_beginscan_catalog(rel, 1, key);
12593 while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
12594 {
12595 Form_pg_class relForm = (Form_pg_class) GETSTRUCT(tuple);
12596 Oid relOid = relForm->oid;
12597
12598 /*
12599 * Do not move objects in pg_catalog as part of this, if an admin
12600 * really wishes to do so, they can issue the individual ALTER
12601 * commands directly.
12602 *
12603 * Also, explicitly avoid any shared tables, temp tables, or TOAST
12604 * (TOAST will be moved with the main table).
12605 */
12606 if (IsCatalogNamespace(relForm->relnamespace) ||
12607 relForm->relisshared ||
12608 isAnyTempNamespace(relForm->relnamespace) ||
12609 IsToastNamespace(relForm->relnamespace))
12610 continue;
12611
12612 /* Only move the object type requested */
12613 if ((stmt->objtype == OBJECT_TABLE &&
12614 relForm->relkind != RELKIND_RELATION &&
12615 relForm->relkind != RELKIND_PARTITIONED_TABLE) ||
12616 (stmt->objtype == OBJECT_INDEX &&
12617 relForm->relkind != RELKIND_INDEX &&
12618 relForm->relkind != RELKIND_PARTITIONED_INDEX) ||
12619 (stmt->objtype == OBJECT_MATVIEW &&
12620 relForm->relkind != RELKIND_MATVIEW))
12621 continue;
12622
12623 /* Check if we are only moving objects owned by certain roles */
12624 if (role_oids != NIL && !list_member_oid(role_oids, relForm->relowner))
12625 continue;
12626
12627 /*
12628 * Handle permissions-checking here since we are locking the tables
12629 * and also to avoid doing a bunch of work only to fail part-way. Note
12630 * that permissions will also be checked by AlterTableInternal().
12631 *
12632 * Caller must be considered an owner on the table to move it.
12633 */
12634 if (!pg_class_ownercheck(relOid, GetUserId()))
12635 aclcheck_error(ACLCHECK_NOT_OWNER, get_relkind_objtype(get_rel_relkind(relOid)),
12636 NameStr(relForm->relname));
12637
12638 if (stmt->nowait &&
12639 !ConditionalLockRelationOid(relOid, AccessExclusiveLock))
12640 ereport(ERROR,
12641 (errcode(ERRCODE_OBJECT_IN_USE),
12642 errmsg("aborting because lock on relation \"%s.%s\" is not available",
12643 get_namespace_name(relForm->relnamespace),
12644 NameStr(relForm->relname))));
12645 else
12646 LockRelationOid(relOid, AccessExclusiveLock);
12647
12648 /* Add to our list of objects to move */
12649 relations = lappend_oid(relations, relOid);
12650 }
12651
12652 table_endscan(scan);
12653 table_close(rel, AccessShareLock);
12654
12655 if (relations == NIL)
12656 ereport(NOTICE,
12657 (errcode(ERRCODE_NO_DATA_FOUND),
12658 errmsg("no matching relations in tablespace \"%s\" found",
12659 orig_tablespaceoid == InvalidOid ? "(database default)" :
12660 get_tablespace_name(orig_tablespaceoid))));
12661
12662 /* Everything is locked, loop through and move all of the relations. */
12663 foreach(l, relations)
12664 {
12665 List *cmds = NIL;
12666 AlterTableCmd *cmd = makeNode(AlterTableCmd);
12667
12668 cmd->subtype = AT_SetTableSpace;
12669 cmd->name = stmt->new_tablespacename;
12670
12671 cmds = lappend(cmds, cmd);
12672
12673 EventTriggerAlterTableStart((Node *) stmt);
12674 /* OID is set by AlterTableInternal */
12675 AlterTableInternal(lfirst_oid(l), cmds, false);
12676 EventTriggerAlterTableEnd();
12677 }
12678
12679 return new_tablespaceoid;
12680}
12681
12682static void
12683index_copy_data(Relation rel, RelFileNode newrnode)
12684{
12685 SMgrRelation dstrel;
12686
12687 dstrel = smgropen(newrnode, rel->rd_backend);
12688 RelationOpenSmgr(rel);
12689
12690 /*
12691 * Since we copy the file directly without looking at the shared buffers,
12692 * we'd better first flush out any pages of the source relation that are
12693 * in shared buffers. We assume no new changes will be made while we are
12694 * holding exclusive lock on the rel.
12695 */
12696 FlushRelationBuffers(rel);
12697
12698 /*
12699 * Create and copy all forks of the relation, and schedule unlinking of
12700 * old physical files.
12701 *
12702 * NOTE: any conflict in relfilenode value will be caught in
12703 * RelationCreateStorage().
12704 */
12705 RelationCreateStorage(newrnode, rel->rd_rel->relpersistence);
12706
12707 /* copy main fork */
12708 RelationCopyStorage(rel->rd_smgr, dstrel, MAIN_FORKNUM,
12709 rel->rd_rel->relpersistence);
12710
12711 /* copy those extra forks that exist */
12712 for (ForkNumber forkNum = MAIN_FORKNUM + 1;
12713 forkNum <= MAX_FORKNUM; forkNum++)
12714 {
12715 if (smgrexists(rel->rd_smgr, forkNum))
12716 {
12717 smgrcreate(dstrel, forkNum, false);
12718
12719 /*
12720 * WAL log creation if the relation is persistent, or this is the
12721 * init fork of an unlogged relation.
12722 */
12723 if (rel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT ||
12724 (rel->rd_rel->relpersistence == RELPERSISTENCE_UNLOGGED &&
12725 forkNum == INIT_FORKNUM))
12726 log_smgrcreate(&newrnode, forkNum);
12727 RelationCopyStorage(rel->rd_smgr, dstrel, forkNum,
12728 rel->rd_rel->relpersistence);
12729 }
12730 }
12731
12732 /* drop old relation, and close new one */
12733 RelationDropStorage(rel);
12734 smgrclose(dstrel);
12735}
12736
12737/*
12738 * ALTER TABLE ENABLE/DISABLE TRIGGER
12739 *
12740 * We just pass this off to trigger.c.
12741 */
12742static void
12743ATExecEnableDisableTrigger(Relation rel, const char *trigname,
12744 char fires_when, bool skip_system, LOCKMODE lockmode)
12745{
12746 EnableDisableTrigger(rel, trigname, fires_when, skip_system, lockmode);
12747}
12748
12749/*
12750 * ALTER TABLE ENABLE/DISABLE RULE
12751 *
12752 * We just pass this off to rewriteDefine.c.
12753 */
12754static void
12755ATExecEnableDisableRule(Relation rel, const char *rulename,
12756 char fires_when, LOCKMODE lockmode)
12757{
12758 EnableDisableRule(rel, rulename, fires_when);
12759}
12760
12761/*
12762 * ALTER TABLE INHERIT
12763 *
12764 * Add a parent to the child's parents. This verifies that all the columns and
12765 * check constraints of the parent appear in the child and that they have the
12766 * same data types and expressions.
12767 */
12768static void
12769ATPrepAddInherit(Relation child_rel)
12770{
12771 if (child_rel->rd_rel->reloftype)
12772 ereport(ERROR,
12773 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
12774 errmsg("cannot change inheritance of typed table")));
12775
12776 if (child_rel->rd_rel->relispartition)
12777 ereport(ERROR,
12778 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
12779 errmsg("cannot change inheritance of a partition")));
12780
12781 if (child_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
12782 ereport(ERROR,
12783 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
12784 errmsg("cannot change inheritance of partitioned table")));
12785}
12786
12787/*
12788 * Return the address of the new parent relation.
12789 */
12790static ObjectAddress
12791ATExecAddInherit(Relation child_rel, RangeVar *parent, LOCKMODE lockmode)
12792{
12793 Relation parent_rel;
12794 List *children;
12795 ObjectAddress address;
12796 const char *trigger_name;
12797
12798 /*
12799 * A self-exclusive lock is needed here. See the similar case in
12800 * MergeAttributes() for a full explanation.
12801 */
12802 parent_rel = table_openrv(parent, ShareUpdateExclusiveLock);
12803
12804 /*
12805 * Must be owner of both parent and child -- child was checked by
12806 * ATSimplePermissions call in ATPrepCmd
12807 */
12808 ATSimplePermissions(parent_rel, ATT_TABLE | ATT_FOREIGN_TABLE);
12809
12810 /* Permanent rels cannot inherit from temporary ones */
12811 if (parent_rel->rd_rel->relpersistence == RELPERSISTENCE_TEMP &&
12812 child_rel->rd_rel->relpersistence != RELPERSISTENCE_TEMP)
12813 ereport(ERROR,
12814 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
12815 errmsg("cannot inherit from temporary relation \"%s\"",
12816 RelationGetRelationName(parent_rel))));
12817
12818 /* If parent rel is temp, it must belong to this session */
12819 if (parent_rel->rd_rel->relpersistence == RELPERSISTENCE_TEMP &&
12820 !parent_rel->rd_islocaltemp)
12821 ereport(ERROR,
12822 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
12823 errmsg("cannot inherit from temporary relation of another session")));
12824
12825 /* Ditto for the child */
12826 if (child_rel->rd_rel->relpersistence == RELPERSISTENCE_TEMP &&
12827 !child_rel->rd_islocaltemp)
12828 ereport(ERROR,
12829 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
12830 errmsg("cannot inherit to temporary relation of another session")));
12831
12832 /* Prevent partitioned tables from becoming inheritance parents */
12833 if (parent_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
12834 ereport(ERROR,
12835 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
12836 errmsg("cannot inherit from partitioned table \"%s\"",
12837 parent->relname)));
12838
12839 /* Likewise for partitions */
12840 if (parent_rel->rd_rel->relispartition)
12841 ereport(ERROR,
12842 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
12843 errmsg("cannot inherit from a partition")));
12844
12845 /*
12846 * Prevent circularity by seeing if proposed parent inherits from child.
12847 * (In particular, this disallows making a rel inherit from itself.)
12848 *
12849 * This is not completely bulletproof because of race conditions: in
12850 * multi-level inheritance trees, someone else could concurrently be
12851 * making another inheritance link that closes the loop but does not join
12852 * either of the rels we have locked. Preventing that seems to require
12853 * exclusive locks on the entire inheritance tree, which is a cure worse
12854 * than the disease. find_all_inheritors() will cope with circularity
12855 * anyway, so don't sweat it too much.
12856 *
12857 * We use weakest lock we can on child's children, namely AccessShareLock.
12858 */
12859 children = find_all_inheritors(RelationGetRelid(child_rel),
12860 AccessShareLock, NULL);
12861
12862 if (list_member_oid(children, RelationGetRelid(parent_rel)))
12863 ereport(ERROR,
12864 (errcode(ERRCODE_DUPLICATE_TABLE),
12865 errmsg("circular inheritance not allowed"),
12866 errdetail("\"%s\" is already a child of \"%s\".",
12867 parent->relname,
12868 RelationGetRelationName(child_rel))));
12869
12870 /*
12871 * If child_rel has row-level triggers with transition tables, we
12872 * currently don't allow it to become an inheritance child. See also
12873 * prohibitions in ATExecAttachPartition() and CreateTrigger().
12874 */
12875 trigger_name = FindTriggerIncompatibleWithInheritance(child_rel->trigdesc);
12876 if (trigger_name != NULL)
12877 ereport(ERROR,
12878 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
12879 errmsg("trigger \"%s\" prevents table \"%s\" from becoming an inheritance child",
12880 trigger_name, RelationGetRelationName(child_rel)),
12881 errdetail("ROW triggers with transition tables are not supported in inheritance hierarchies.")));
12882
12883 /* OK to create inheritance */
12884 CreateInheritance(child_rel, parent_rel);
12885
12886 ObjectAddressSet(address, RelationRelationId,
12887 RelationGetRelid(parent_rel));
12888
12889 /* keep our lock on the parent relation until commit */
12890 table_close(parent_rel, NoLock);
12891
12892 return address;
12893}
12894
12895/*
12896 * CreateInheritance
12897 * Catalog manipulation portion of creating inheritance between a child
12898 * table and a parent table.
12899 *
12900 * Common to ATExecAddInherit() and ATExecAttachPartition().
12901 */
12902static void
12903CreateInheritance(Relation child_rel, Relation parent_rel)
12904{
12905 Relation catalogRelation;
12906 SysScanDesc scan;
12907 ScanKeyData key;
12908 HeapTuple inheritsTuple;
12909 int32 inhseqno;
12910
12911 /* Note: get RowExclusiveLock because we will write pg_inherits below. */
12912 catalogRelation = table_open(InheritsRelationId, RowExclusiveLock);
12913
12914 /*
12915 * Check for duplicates in the list of parents, and determine the highest
12916 * inhseqno already present; we'll use the next one for the new parent.
12917 * Also, if proposed child is a partition, it cannot already be
12918 * inheriting.
12919 *
12920 * Note: we do not reject the case where the child already inherits from
12921 * the parent indirectly; CREATE TABLE doesn't reject comparable cases.
12922 */
12923 ScanKeyInit(&key,
12924 Anum_pg_inherits_inhrelid,
12925 BTEqualStrategyNumber, F_OIDEQ,
12926 ObjectIdGetDatum(RelationGetRelid(child_rel)));
12927 scan = systable_beginscan(catalogRelation, InheritsRelidSeqnoIndexId,
12928 true, NULL, 1, &key);
12929
12930 /* inhseqno sequences start at 1 */
12931 inhseqno = 0;
12932 while (HeapTupleIsValid(inheritsTuple = systable_getnext(scan)))
12933 {
12934 Form_pg_inherits inh = (Form_pg_inherits) GETSTRUCT(inheritsTuple);
12935
12936 if (inh->inhparent == RelationGetRelid(parent_rel))
12937 ereport(ERROR,
12938 (errcode(ERRCODE_DUPLICATE_TABLE),
12939 errmsg("relation \"%s\" would be inherited from more than once",
12940 RelationGetRelationName(parent_rel))));
12941
12942 if (inh->inhseqno > inhseqno)
12943 inhseqno = inh->inhseqno;
12944 }
12945 systable_endscan(scan);
12946
12947 /* Match up the columns and bump attinhcount as needed */
12948 MergeAttributesIntoExisting(child_rel, parent_rel);
12949
12950 /* Match up the constraints and bump coninhcount as needed */
12951 MergeConstraintsIntoExisting(child_rel, parent_rel);
12952
12953 /*
12954 * OK, it looks valid. Make the catalog entries that show inheritance.
12955 */
12956 StoreCatalogInheritance1(RelationGetRelid(child_rel),
12957 RelationGetRelid(parent_rel),
12958 inhseqno + 1,
12959 catalogRelation,
12960 parent_rel->rd_rel->relkind ==
12961 RELKIND_PARTITIONED_TABLE);
12962
12963 /* Now we're done with pg_inherits */
12964 table_close(catalogRelation, RowExclusiveLock);
12965}
12966
12967/*
12968 * Obtain the source-text form of the constraint expression for a check
12969 * constraint, given its pg_constraint tuple
12970 */
12971static char *
12972decompile_conbin(HeapTuple contup, TupleDesc tupdesc)
12973{
12974 Form_pg_constraint con;
12975 bool isnull;
12976 Datum attr;
12977 Datum expr;
12978
12979 con = (Form_pg_constraint) GETSTRUCT(contup);
12980 attr = heap_getattr(contup, Anum_pg_constraint_conbin, tupdesc, &isnull);
12981 if (isnull)
12982 elog(ERROR, "null conbin for constraint %u", con->oid);
12983
12984 expr = DirectFunctionCall2(pg_get_expr, attr,
12985 ObjectIdGetDatum(con->conrelid));
12986 return TextDatumGetCString(expr);
12987}
12988
12989/*
12990 * Determine whether two check constraints are functionally equivalent
12991 *
12992 * The test we apply is to see whether they reverse-compile to the same
12993 * source string. This insulates us from issues like whether attributes
12994 * have the same physical column numbers in parent and child relations.
12995 */
12996static bool
12997constraints_equivalent(HeapTuple a, HeapTuple b, TupleDesc tupleDesc)
12998{
12999 Form_pg_constraint acon = (Form_pg_constraint) GETSTRUCT(a);
13000 Form_pg_constraint bcon = (Form_pg_constraint) GETSTRUCT(b);
13001
13002 if (acon->condeferrable != bcon->condeferrable ||
13003 acon->condeferred != bcon->condeferred ||
13004 strcmp(decompile_conbin(a, tupleDesc),
13005 decompile_conbin(b, tupleDesc)) != 0)
13006 return false;
13007 else
13008 return true;
13009}
13010
13011/*
13012 * Check columns in child table match up with columns in parent, and increment
13013 * their attinhcount.
13014 *
13015 * Called by CreateInheritance
13016 *
13017 * Currently all parent columns must be found in child. Missing columns are an
13018 * error. One day we might consider creating new columns like CREATE TABLE
13019 * does. However, that is widely unpopular --- in the common use case of
13020 * partitioned tables it's a foot-gun.
13021 *
13022 * The data type must match exactly. If the parent column is NOT NULL then
13023 * the child must be as well. Defaults are not compared, however.
13024 */
13025static void
13026MergeAttributesIntoExisting(Relation child_rel, Relation parent_rel)
13027{
13028 Relation attrrel;
13029 AttrNumber parent_attno;
13030 int parent_natts;
13031 TupleDesc tupleDesc;
13032 HeapTuple tuple;
13033 bool child_is_partition = false;
13034
13035 attrrel = table_open(AttributeRelationId, RowExclusiveLock);
13036
13037 tupleDesc = RelationGetDescr(parent_rel);
13038 parent_natts = tupleDesc->natts;
13039
13040 /* If parent_rel is a partitioned table, child_rel must be a partition */
13041 if (parent_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
13042 child_is_partition = true;
13043
13044 for (parent_attno = 1; parent_attno <= parent_natts; parent_attno++)
13045 {
13046 Form_pg_attribute attribute = TupleDescAttr(tupleDesc,
13047 parent_attno - 1);
13048 char *attributeName = NameStr(attribute->attname);
13049
13050 /* Ignore dropped columns in the parent. */
13051 if (attribute->attisdropped)
13052 continue;
13053
13054 /* Find same column in child (matching on column name). */
13055 tuple = SearchSysCacheCopyAttName(RelationGetRelid(child_rel),
13056 attributeName);
13057 if (HeapTupleIsValid(tuple))
13058 {
13059 /* Check they are same type, typmod, and collation */
13060 Form_pg_attribute childatt = (Form_pg_attribute) GETSTRUCT(tuple);
13061
13062 if (attribute->atttypid != childatt->atttypid ||
13063 attribute->atttypmod != childatt->atttypmod)
13064 ereport(ERROR,
13065 (errcode(ERRCODE_DATATYPE_MISMATCH),
13066 errmsg("child table \"%s\" has different type for column \"%s\"",
13067 RelationGetRelationName(child_rel),
13068 attributeName)));
13069
13070 if (attribute->attcollation != childatt->attcollation)
13071 ereport(ERROR,
13072 (errcode(ERRCODE_COLLATION_MISMATCH),
13073 errmsg("child table \"%s\" has different collation for column \"%s\"",
13074 RelationGetRelationName(child_rel),
13075 attributeName)));
13076
13077 /*
13078 * Check child doesn't discard NOT NULL property. (Other
13079 * constraints are checked elsewhere.)
13080 */
13081 if (attribute->attnotnull && !childatt->attnotnull)
13082 ereport(ERROR,
13083 (errcode(ERRCODE_DATATYPE_MISMATCH),
13084 errmsg("column \"%s\" in child table must be marked NOT NULL",
13085 attributeName)));
13086
13087 /*
13088 * OK, bump the child column's inheritance count. (If we fail
13089 * later on, this change will just roll back.)
13090 */
13091 childatt->attinhcount++;
13092
13093 /*
13094 * In case of partitions, we must enforce that value of attislocal
13095 * is same in all partitions. (Note: there are only inherited
13096 * attributes in partitions)
13097 */
13098 if (child_is_partition)
13099 {
13100 Assert(childatt->attinhcount == 1);
13101 childatt->attislocal = false;
13102 }
13103
13104 CatalogTupleUpdate(attrrel, &tuple->t_self, tuple);
13105 heap_freetuple(tuple);
13106 }
13107 else
13108 {
13109 ereport(ERROR,
13110 (errcode(ERRCODE_DATATYPE_MISMATCH),
13111 errmsg("child table is missing column \"%s\"",
13112 attributeName)));
13113 }
13114 }
13115
13116 table_close(attrrel, RowExclusiveLock);
13117}
13118
13119/*
13120 * Check constraints in child table match up with constraints in parent,
13121 * and increment their coninhcount.
13122 *
13123 * Constraints that are marked ONLY in the parent are ignored.
13124 *
13125 * Called by CreateInheritance
13126 *
13127 * Currently all constraints in parent must be present in the child. One day we
13128 * may consider adding new constraints like CREATE TABLE does.
13129 *
13130 * XXX This is O(N^2) which may be an issue with tables with hundreds of
13131 * constraints. As long as tables have more like 10 constraints it shouldn't be
13132 * a problem though. Even 100 constraints ought not be the end of the world.
13133 *
13134 * XXX See MergeWithExistingConstraint too if you change this code.
13135 */
13136static void
13137MergeConstraintsIntoExisting(Relation child_rel, Relation parent_rel)
13138{
13139 Relation catalog_relation;
13140 TupleDesc tuple_desc;
13141 SysScanDesc parent_scan;
13142 ScanKeyData parent_key;
13143 HeapTuple parent_tuple;
13144 bool child_is_partition = false;
13145
13146 catalog_relation = table_open(ConstraintRelationId, RowExclusiveLock);
13147 tuple_desc = RelationGetDescr(catalog_relation);
13148
13149 /* If parent_rel is a partitioned table, child_rel must be a partition */
13150 if (parent_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
13151 child_is_partition = true;
13152
13153 /* Outer loop scans through the parent's constraint definitions */
13154 ScanKeyInit(&parent_key,
13155 Anum_pg_constraint_conrelid,
13156 BTEqualStrategyNumber, F_OIDEQ,
13157 ObjectIdGetDatum(RelationGetRelid(parent_rel)));
13158 parent_scan = systable_beginscan(catalog_relation, ConstraintRelidTypidNameIndexId,
13159 true, NULL, 1, &parent_key);
13160
13161 while (HeapTupleIsValid(parent_tuple = systable_getnext(parent_scan)))
13162 {
13163 Form_pg_constraint parent_con = (Form_pg_constraint) GETSTRUCT(parent_tuple);
13164 SysScanDesc child_scan;
13165 ScanKeyData child_key;
13166 HeapTuple child_tuple;
13167 bool found = false;
13168
13169 if (parent_con->contype != CONSTRAINT_CHECK)
13170 continue;
13171
13172 /* if the parent's constraint is marked NO INHERIT, it's not inherited */
13173 if (parent_con->connoinherit)
13174 continue;
13175
13176 /* Search for a child constraint matching this one */
13177 ScanKeyInit(&child_key,
13178 Anum_pg_constraint_conrelid,
13179 BTEqualStrategyNumber, F_OIDEQ,
13180 ObjectIdGetDatum(RelationGetRelid(child_rel)));
13181 child_scan = systable_beginscan(catalog_relation, ConstraintRelidTypidNameIndexId,
13182 true, NULL, 1, &child_key);
13183
13184 while (HeapTupleIsValid(child_tuple = systable_getnext(child_scan)))
13185 {
13186 Form_pg_constraint child_con = (Form_pg_constraint) GETSTRUCT(child_tuple);
13187 HeapTuple child_copy;
13188
13189 if (child_con->contype != CONSTRAINT_CHECK)
13190 continue;
13191
13192 if (strcmp(NameStr(parent_con->conname),
13193 NameStr(child_con->conname)) != 0)
13194 continue;
13195
13196 if (!constraints_equivalent(parent_tuple, child_tuple, tuple_desc))
13197 ereport(ERROR,
13198 (errcode(ERRCODE_DATATYPE_MISMATCH),
13199 errmsg("child table \"%s\" has different definition for check constraint \"%s\"",
13200 RelationGetRelationName(child_rel),
13201 NameStr(parent_con->conname))));
13202
13203 /* If the child constraint is "no inherit" then cannot merge */
13204 if (child_con->connoinherit)
13205 ereport(ERROR,
13206 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
13207 errmsg("constraint \"%s\" conflicts with non-inherited constraint on child table \"%s\"",
13208 NameStr(child_con->conname),
13209 RelationGetRelationName(child_rel))));
13210
13211 /*
13212 * If the child constraint is "not valid" then cannot merge with a
13213 * valid parent constraint
13214 */
13215 if (parent_con->convalidated && !child_con->convalidated)
13216 ereport(ERROR,
13217 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
13218 errmsg("constraint \"%s\" conflicts with NOT VALID constraint on child table \"%s\"",
13219 NameStr(child_con->conname),
13220 RelationGetRelationName(child_rel))));
13221
13222 /*
13223 * OK, bump the child constraint's inheritance count. (If we fail
13224 * later on, this change will just roll back.)
13225 */
13226 child_copy = heap_copytuple(child_tuple);
13227 child_con = (Form_pg_constraint) GETSTRUCT(child_copy);
13228 child_con->coninhcount++;
13229
13230 /*
13231 * In case of partitions, an inherited constraint must be
13232 * inherited only once since it cannot have multiple parents and
13233 * it is never considered local.
13234 */
13235 if (child_is_partition)
13236 {
13237 Assert(child_con->coninhcount == 1);
13238 child_con->conislocal = false;
13239 }
13240
13241 CatalogTupleUpdate(catalog_relation, &child_copy->t_self, child_copy);
13242 heap_freetuple(child_copy);
13243
13244 found = true;
13245 break;
13246 }
13247
13248 systable_endscan(child_scan);
13249
13250 if (!found)
13251 ereport(ERROR,
13252 (errcode(ERRCODE_DATATYPE_MISMATCH),
13253 errmsg("child table is missing constraint \"%s\"",
13254 NameStr(parent_con->conname))));
13255 }
13256
13257 systable_endscan(parent_scan);
13258 table_close(catalog_relation, RowExclusiveLock);
13259}
13260
13261/*
13262 * ALTER TABLE NO INHERIT
13263 *
13264 * Return value is the address of the relation that is no longer parent.
13265 */
13266static ObjectAddress
13267ATExecDropInherit(Relation rel, RangeVar *parent, LOCKMODE lockmode)
13268{
13269 ObjectAddress address;
13270 Relation parent_rel;
13271
13272 if (rel->rd_rel->relispartition)
13273 ereport(ERROR,
13274 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
13275 errmsg("cannot change inheritance of a partition")));
13276
13277 /*
13278 * AccessShareLock on the parent is probably enough, seeing that DROP
13279 * TABLE doesn't lock parent tables at all. We need some lock since we'll
13280 * be inspecting the parent's schema.
13281 */
13282 parent_rel = table_openrv(parent, AccessShareLock);
13283
13284 /*
13285 * We don't bother to check ownership of the parent table --- ownership of
13286 * the child is presumed enough rights.
13287 */
13288
13289 /* Off to RemoveInheritance() where most of the work happens */
13290 RemoveInheritance(rel, parent_rel);
13291
13292 ObjectAddressSet(address, RelationRelationId,
13293 RelationGetRelid(parent_rel));
13294
13295 /* keep our lock on the parent relation until commit */
13296 table_close(parent_rel, NoLock);
13297
13298 return address;
13299}
13300
13301/*
13302 * RemoveInheritance
13303 *
13304 * Drop a parent from the child's parents. This just adjusts the attinhcount
13305 * and attislocal of the columns and removes the pg_inherit and pg_depend
13306 * entries.
13307 *
13308 * If attinhcount goes to 0 then attislocal gets set to true. If it goes back
13309 * up attislocal stays true, which means if a child is ever removed from a
13310 * parent then its columns will never be automatically dropped which may
13311 * surprise. But at least we'll never surprise by dropping columns someone
13312 * isn't expecting to be dropped which would actually mean data loss.
13313 *
13314 * coninhcount and conislocal for inherited constraints are adjusted in
13315 * exactly the same way.
13316 *
13317 * Common to ATExecDropInherit() and ATExecDetachPartition().
13318 */
13319static void
13320RemoveInheritance(Relation child_rel, Relation parent_rel)
13321{
13322 Relation catalogRelation;
13323 SysScanDesc scan;
13324 ScanKeyData key[3];
13325 HeapTuple attributeTuple,
13326 constraintTuple;
13327 List *connames;
13328 bool found;
13329 bool child_is_partition = false;
13330
13331 /* If parent_rel is a partitioned table, child_rel must be a partition */
13332 if (parent_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
13333 child_is_partition = true;
13334
13335 found = DeleteInheritsTuple(RelationGetRelid(child_rel),
13336 RelationGetRelid(parent_rel));
13337 if (!found)
13338 {
13339 if (child_is_partition)
13340 ereport(ERROR,
13341 (errcode(ERRCODE_UNDEFINED_TABLE),
13342 errmsg("relation \"%s\" is not a partition of relation \"%s\"",
13343 RelationGetRelationName(child_rel),
13344 RelationGetRelationName(parent_rel))));
13345 else
13346 ereport(ERROR,
13347 (errcode(ERRCODE_UNDEFINED_TABLE),
13348 errmsg("relation \"%s\" is not a parent of relation \"%s\"",
13349 RelationGetRelationName(parent_rel),
13350 RelationGetRelationName(child_rel))));
13351 }
13352
13353 /*
13354 * Search through child columns looking for ones matching parent rel
13355 */
13356 catalogRelation = table_open(AttributeRelationId, RowExclusiveLock);
13357 ScanKeyInit(&key[0],
13358 Anum_pg_attribute_attrelid,
13359 BTEqualStrategyNumber, F_OIDEQ,
13360 ObjectIdGetDatum(RelationGetRelid(child_rel)));
13361 scan = systable_beginscan(catalogRelation, AttributeRelidNumIndexId,
13362 true, NULL, 1, key);
13363 while (HeapTupleIsValid(attributeTuple = systable_getnext(scan)))
13364 {
13365 Form_pg_attribute att = (Form_pg_attribute) GETSTRUCT(attributeTuple);
13366
13367 /* Ignore if dropped or not inherited */
13368 if (att->attisdropped)
13369 continue;
13370 if (att->attinhcount <= 0)
13371 continue;
13372
13373 if (SearchSysCacheExistsAttName(RelationGetRelid(parent_rel),
13374 NameStr(att->attname)))
13375 {
13376 /* Decrement inhcount and possibly set islocal to true */
13377 HeapTuple copyTuple = heap_copytuple(attributeTuple);
13378 Form_pg_attribute copy_att = (Form_pg_attribute) GETSTRUCT(copyTuple);
13379
13380 copy_att->attinhcount--;
13381 if (copy_att->attinhcount == 0)
13382 copy_att->attislocal = true;
13383
13384 CatalogTupleUpdate(catalogRelation, &copyTuple->t_self, copyTuple);
13385 heap_freetuple(copyTuple);
13386 }
13387 }
13388 systable_endscan(scan);
13389 table_close(catalogRelation, RowExclusiveLock);
13390
13391 /*
13392 * Likewise, find inherited check constraints and disinherit them. To do
13393 * this, we first need a list of the names of the parent's check
13394 * constraints. (We cheat a bit by only checking for name matches,
13395 * assuming that the expressions will match.)
13396 */
13397 catalogRelation = table_open(ConstraintRelationId, RowExclusiveLock);
13398 ScanKeyInit(&key[0],
13399 Anum_pg_constraint_conrelid,
13400 BTEqualStrategyNumber, F_OIDEQ,
13401 ObjectIdGetDatum(RelationGetRelid(parent_rel)));
13402 scan = systable_beginscan(catalogRelation, ConstraintRelidTypidNameIndexId,
13403 true, NULL, 1, key);
13404
13405 connames = NIL;
13406
13407 while (HeapTupleIsValid(constraintTuple = systable_getnext(scan)))
13408 {
13409 Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(constraintTuple);
13410
13411 if (con->contype == CONSTRAINT_CHECK)
13412 connames = lappend(connames, pstrdup(NameStr(con->conname)));
13413 }
13414
13415 systable_endscan(scan);
13416
13417 /* Now scan the child's constraints */
13418 ScanKeyInit(&key[0],
13419 Anum_pg_constraint_conrelid,
13420 BTEqualStrategyNumber, F_OIDEQ,
13421 ObjectIdGetDatum(RelationGetRelid(child_rel)));
13422 scan = systable_beginscan(catalogRelation, ConstraintRelidTypidNameIndexId,
13423 true, NULL, 1, key);
13424
13425 while (HeapTupleIsValid(constraintTuple = systable_getnext(scan)))
13426 {
13427 Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(constraintTuple);
13428 bool match;
13429 ListCell *lc;
13430
13431 if (con->contype != CONSTRAINT_CHECK)
13432 continue;
13433
13434 match = false;
13435 foreach(lc, connames)
13436 {
13437 if (strcmp(NameStr(con->conname), (char *) lfirst(lc)) == 0)
13438 {
13439 match = true;
13440 break;
13441 }
13442 }
13443
13444 if (match)
13445 {
13446 /* Decrement inhcount and possibly set islocal to true */
13447 HeapTuple copyTuple = heap_copytuple(constraintTuple);
13448 Form_pg_constraint copy_con = (Form_pg_constraint) GETSTRUCT(copyTuple);
13449
13450 if (copy_con->coninhcount <= 0) /* shouldn't happen */
13451 elog(ERROR, "relation %u has non-inherited constraint \"%s\"",
13452 RelationGetRelid(child_rel), NameStr(copy_con->conname));
13453
13454 copy_con->coninhcount--;
13455 if (copy_con->coninhcount == 0)
13456 copy_con->conislocal = true;
13457
13458 CatalogTupleUpdate(catalogRelation, &copyTuple->t_self, copyTuple);
13459 heap_freetuple(copyTuple);
13460 }
13461 }
13462
13463 systable_endscan(scan);
13464 table_close(catalogRelation, RowExclusiveLock);
13465
13466 drop_parent_dependency(RelationGetRelid(child_rel),
13467 RelationRelationId,
13468 RelationGetRelid(parent_rel),
13469 child_dependency_type(child_is_partition));
13470
13471 /*
13472 * Post alter hook of this inherits. Since object_access_hook doesn't take
13473 * multiple object identifiers, we relay oid of parent relation using
13474 * auxiliary_id argument.
13475 */
13476 InvokeObjectPostAlterHookArg(InheritsRelationId,
13477 RelationGetRelid(child_rel), 0,
13478 RelationGetRelid(parent_rel), false);
13479}
13480
13481/*
13482 * Drop the dependency created by StoreCatalogInheritance1 (CREATE TABLE
13483 * INHERITS/ALTER TABLE INHERIT -- refclassid will be RelationRelationId) or
13484 * heap_create_with_catalog (CREATE TABLE OF/ALTER TABLE OF -- refclassid will
13485 * be TypeRelationId). There's no convenient way to do this, so go trawling
13486 * through pg_depend.
13487 */
13488static void
13489drop_parent_dependency(Oid relid, Oid refclassid, Oid refobjid,
13490 DependencyType deptype)
13491{
13492 Relation catalogRelation;
13493 SysScanDesc scan;
13494 ScanKeyData key[3];
13495 HeapTuple depTuple;
13496
13497 catalogRelation = table_open(DependRelationId, RowExclusiveLock);
13498
13499 ScanKeyInit(&key[0],
13500 Anum_pg_depend_classid,
13501 BTEqualStrategyNumber, F_OIDEQ,
13502 ObjectIdGetDatum(RelationRelationId));
13503 ScanKeyInit(&key[1],
13504 Anum_pg_depend_objid,
13505 BTEqualStrategyNumber, F_OIDEQ,
13506 ObjectIdGetDatum(relid));
13507 ScanKeyInit(&key[2],
13508 Anum_pg_depend_objsubid,
13509 BTEqualStrategyNumber, F_INT4EQ,
13510 Int32GetDatum(0));
13511
13512 scan = systable_beginscan(catalogRelation, DependDependerIndexId, true,
13513 NULL, 3, key);
13514
13515 while (HeapTupleIsValid(depTuple = systable_getnext(scan)))
13516 {
13517 Form_pg_depend dep = (Form_pg_depend) GETSTRUCT(depTuple);
13518
13519 if (dep->refclassid == refclassid &&
13520 dep->refobjid == refobjid &&
13521 dep->refobjsubid == 0 &&
13522 dep->deptype == deptype)
13523 CatalogTupleDelete(catalogRelation, &depTuple->t_self);
13524 }
13525
13526 systable_endscan(scan);
13527 table_close(catalogRelation, RowExclusiveLock);
13528}
13529
13530/*
13531 * ALTER TABLE OF
13532 *
13533 * Attach a table to a composite type, as though it had been created with CREATE
13534 * TABLE OF. All attname, atttypid, atttypmod and attcollation must match. The
13535 * subject table must not have inheritance parents. These restrictions ensure
13536 * that you cannot create a configuration impossible with CREATE TABLE OF alone.
13537 *
13538 * The address of the type is returned.
13539 */
13540static ObjectAddress
13541ATExecAddOf(Relation rel, const TypeName *ofTypename, LOCKMODE lockmode)
13542{
13543 Oid relid = RelationGetRelid(rel);
13544 Type typetuple;
13545 Form_pg_type typeform;
13546 Oid typeid;
13547 Relation inheritsRelation,
13548 relationRelation;
13549 SysScanDesc scan;
13550 ScanKeyData key;
13551 AttrNumber table_attno,
13552 type_attno;
13553 TupleDesc typeTupleDesc,
13554 tableTupleDesc;
13555 ObjectAddress tableobj,
13556 typeobj;
13557 HeapTuple classtuple;
13558
13559 /* Validate the type. */
13560 typetuple = typenameType(NULL, ofTypename, NULL);
13561 check_of_type(typetuple);
13562 typeform = (Form_pg_type) GETSTRUCT(typetuple);
13563 typeid = typeform->oid;
13564
13565 /* Fail if the table has any inheritance parents. */
13566 inheritsRelation = table_open(InheritsRelationId, AccessShareLock);
13567 ScanKeyInit(&key,
13568 Anum_pg_inherits_inhrelid,
13569 BTEqualStrategyNumber, F_OIDEQ,
13570 ObjectIdGetDatum(relid));
13571 scan = systable_beginscan(inheritsRelation, InheritsRelidSeqnoIndexId,
13572 true, NULL, 1, &key);
13573 if (HeapTupleIsValid(systable_getnext(scan)))
13574 ereport(ERROR,
13575 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
13576 errmsg("typed tables cannot inherit")));
13577 systable_endscan(scan);
13578 table_close(inheritsRelation, AccessShareLock);
13579
13580 /*
13581 * Check the tuple descriptors for compatibility. Unlike inheritance, we
13582 * require that the order also match. However, attnotnull need not match.
13583 */
13584 typeTupleDesc = lookup_rowtype_tupdesc(typeid, -1);
13585 tableTupleDesc = RelationGetDescr(rel);
13586 table_attno = 1;
13587 for (type_attno = 1; type_attno <= typeTupleDesc->natts; type_attno++)
13588 {
13589 Form_pg_attribute type_attr,
13590 table_attr;
13591 const char *type_attname,
13592 *table_attname;
13593
13594 /* Get the next non-dropped type attribute. */
13595 type_attr = TupleDescAttr(typeTupleDesc, type_attno - 1);
13596 if (type_attr->attisdropped)
13597 continue;
13598 type_attname = NameStr(type_attr->attname);
13599
13600 /* Get the next non-dropped table attribute. */
13601 do
13602 {
13603 if (table_attno > tableTupleDesc->natts)
13604 ereport(ERROR,
13605 (errcode(ERRCODE_DATATYPE_MISMATCH),
13606 errmsg("table is missing column \"%s\"",
13607 type_attname)));
13608 table_attr = TupleDescAttr(tableTupleDesc, table_attno - 1);
13609 table_attno++;
13610 } while (table_attr->attisdropped);
13611 table_attname = NameStr(table_attr->attname);
13612
13613 /* Compare name. */
13614 if (strncmp(table_attname, type_attname, NAMEDATALEN) != 0)
13615 ereport(ERROR,
13616 (errcode(ERRCODE_DATATYPE_MISMATCH),
13617 errmsg("table has column \"%s\" where type requires \"%s\"",
13618 table_attname, type_attname)));
13619
13620 /* Compare type. */
13621 if (table_attr->atttypid != type_attr->atttypid ||
13622 table_attr->atttypmod != type_attr->atttypmod ||
13623 table_attr->attcollation != type_attr->attcollation)
13624 ereport(ERROR,
13625 (errcode(ERRCODE_DATATYPE_MISMATCH),
13626 errmsg("table \"%s\" has different type for column \"%s\"",
13627 RelationGetRelationName(rel), type_attname)));
13628 }
13629 DecrTupleDescRefCount(typeTupleDesc);
13630
13631 /* Any remaining columns at the end of the table had better be dropped. */
13632 for (; table_attno <= tableTupleDesc->natts; table_attno++)
13633 {
13634 Form_pg_attribute table_attr = TupleDescAttr(tableTupleDesc,
13635 table_attno - 1);
13636
13637 if (!table_attr->attisdropped)
13638 ereport(ERROR,
13639 (errcode(ERRCODE_DATATYPE_MISMATCH),
13640 errmsg("table has extra column \"%s\"",
13641 NameStr(table_attr->attname))));
13642 }
13643
13644 /* If the table was already typed, drop the existing dependency. */
13645 if (rel->rd_rel->reloftype)
13646 drop_parent_dependency(relid, TypeRelationId, rel->rd_rel->reloftype,
13647 DEPENDENCY_NORMAL);
13648
13649 /* Record a dependency on the new type. */
13650 tableobj.classId = RelationRelationId;
13651 tableobj.objectId = relid;
13652 tableobj.objectSubId = 0;
13653 typeobj.classId = TypeRelationId;
13654 typeobj.objectId = typeid;
13655 typeobj.objectSubId = 0;
13656 recordDependencyOn(&tableobj, &typeobj, DEPENDENCY_NORMAL);
13657
13658 /* Update pg_class.reloftype */
13659 relationRelation = table_open(RelationRelationId, RowExclusiveLock);
13660 classtuple = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(relid));
13661 if (!HeapTupleIsValid(classtuple))
13662 elog(ERROR, "cache lookup failed for relation %u", relid);
13663 ((Form_pg_class) GETSTRUCT(classtuple))->reloftype = typeid;
13664 CatalogTupleUpdate(relationRelation, &classtuple->t_self, classtuple);
13665
13666 InvokeObjectPostAlterHook(RelationRelationId, relid, 0);
13667
13668 heap_freetuple(classtuple);
13669 table_close(relationRelation, RowExclusiveLock);
13670
13671 ReleaseSysCache(typetuple);
13672
13673 return typeobj;
13674}
13675
13676/*
13677 * ALTER TABLE NOT OF
13678 *
13679 * Detach a typed table from its originating type. Just clear reloftype and
13680 * remove the dependency.
13681 */
13682static void
13683ATExecDropOf(Relation rel, LOCKMODE lockmode)
13684{
13685 Oid relid = RelationGetRelid(rel);
13686 Relation relationRelation;
13687 HeapTuple tuple;
13688
13689 if (!OidIsValid(rel->rd_rel->reloftype))
13690 ereport(ERROR,
13691 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
13692 errmsg("\"%s\" is not a typed table",
13693 RelationGetRelationName(rel))));
13694
13695 /*
13696 * We don't bother to check ownership of the type --- ownership of the
13697 * table is presumed enough rights. No lock required on the type, either.
13698 */
13699
13700 drop_parent_dependency(relid, TypeRelationId, rel->rd_rel->reloftype,
13701 DEPENDENCY_NORMAL);
13702
13703 /* Clear pg_class.reloftype */
13704 relationRelation = table_open(RelationRelationId, RowExclusiveLock);
13705 tuple = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(relid));
13706 if (!HeapTupleIsValid(tuple))
13707 elog(ERROR, "cache lookup failed for relation %u", relid);
13708 ((Form_pg_class) GETSTRUCT(tuple))->reloftype = InvalidOid;
13709 CatalogTupleUpdate(relationRelation, &tuple->t_self, tuple);
13710
13711 InvokeObjectPostAlterHook(RelationRelationId, relid, 0);
13712
13713 heap_freetuple(tuple);
13714 table_close(relationRelation, RowExclusiveLock);
13715}
13716
13717/*
13718 * relation_mark_replica_identity: Update a table's replica identity
13719 *
13720 * Iff ri_type = REPLICA_IDENTITY_INDEX, indexOid must be the Oid of a suitable
13721 * index. Otherwise, it should be InvalidOid.
13722 */
13723static void
13724relation_mark_replica_identity(Relation rel, char ri_type, Oid indexOid,
13725 bool is_internal)
13726{
13727 Relation pg_index;
13728 Relation pg_class;
13729 HeapTuple pg_class_tuple;
13730 HeapTuple pg_index_tuple;
13731 Form_pg_class pg_class_form;
13732 Form_pg_index pg_index_form;
13733
13734 ListCell *index;
13735
13736 /*
13737 * Check whether relreplident has changed, and update it if so.
13738 */
13739 pg_class = table_open(RelationRelationId, RowExclusiveLock);
13740 pg_class_tuple = SearchSysCacheCopy1(RELOID,
13741 ObjectIdGetDatum(RelationGetRelid(rel)));
13742 if (!HeapTupleIsValid(pg_class_tuple))
13743 elog(ERROR, "cache lookup failed for relation \"%s\"",
13744 RelationGetRelationName(rel));
13745 pg_class_form = (Form_pg_class) GETSTRUCT(pg_class_tuple);
13746 if (pg_class_form->relreplident != ri_type)
13747 {
13748 pg_class_form->relreplident = ri_type;
13749 CatalogTupleUpdate(pg_class, &pg_class_tuple->t_self, pg_class_tuple);
13750 }
13751 table_close(pg_class, RowExclusiveLock);
13752 heap_freetuple(pg_class_tuple);
13753
13754 /*
13755 * Check whether the correct index is marked indisreplident; if so, we're
13756 * done.
13757 */
13758 if (OidIsValid(indexOid))
13759 {
13760 Assert(ri_type == REPLICA_IDENTITY_INDEX);
13761
13762 pg_index_tuple = SearchSysCache1(INDEXRELID, ObjectIdGetDatum(indexOid));
13763 if (!HeapTupleIsValid(pg_index_tuple))
13764 elog(ERROR, "cache lookup failed for index %u", indexOid);
13765 pg_index_form = (Form_pg_index) GETSTRUCT(pg_index_tuple);
13766
13767 if (pg_index_form->indisreplident)
13768 {
13769 ReleaseSysCache(pg_index_tuple);
13770 return;
13771 }
13772 ReleaseSysCache(pg_index_tuple);
13773 }
13774
13775 /*
13776 * Clear the indisreplident flag from any index that had it previously,
13777 * and set it for any index that should have it now.
13778 */
13779 pg_index = table_open(IndexRelationId, RowExclusiveLock);
13780 foreach(index, RelationGetIndexList(rel))
13781 {
13782 Oid thisIndexOid = lfirst_oid(index);
13783 bool dirty = false;
13784
13785 pg_index_tuple = SearchSysCacheCopy1(INDEXRELID,
13786 ObjectIdGetDatum(thisIndexOid));
13787 if (!HeapTupleIsValid(pg_index_tuple))
13788 elog(ERROR, "cache lookup failed for index %u", thisIndexOid);
13789 pg_index_form = (Form_pg_index) GETSTRUCT(pg_index_tuple);
13790
13791 /*
13792 * Unset the bit if set. We know it's wrong because we checked this
13793 * earlier.
13794 */
13795 if (pg_index_form->indisreplident)
13796 {
13797 dirty = true;
13798 pg_index_form->indisreplident = false;
13799 }
13800 else if (thisIndexOid == indexOid)
13801 {
13802 dirty = true;
13803 pg_index_form->indisreplident = true;
13804 }
13805
13806 if (dirty)
13807 {
13808 CatalogTupleUpdate(pg_index, &pg_index_tuple->t_self, pg_index_tuple);
13809 InvokeObjectPostAlterHookArg(IndexRelationId, thisIndexOid, 0,
13810 InvalidOid, is_internal);
13811 }
13812 heap_freetuple(pg_index_tuple);
13813 }
13814
13815 table_close(pg_index, RowExclusiveLock);
13816}
13817
13818/*
13819 * ALTER TABLE <name> REPLICA IDENTITY ...
13820 */
13821static void
13822ATExecReplicaIdentity(Relation rel, ReplicaIdentityStmt *stmt, LOCKMODE lockmode)
13823{
13824 Oid indexOid;
13825 Relation indexRel;
13826 int key;
13827
13828 if (stmt->identity_type == REPLICA_IDENTITY_DEFAULT)
13829 {
13830 relation_mark_replica_identity(rel, stmt->identity_type, InvalidOid, true);
13831 return;
13832 }
13833 else if (stmt->identity_type == REPLICA_IDENTITY_FULL)
13834 {
13835 relation_mark_replica_identity(rel, stmt->identity_type, InvalidOid, true);
13836 return;
13837 }
13838 else if (stmt->identity_type == REPLICA_IDENTITY_NOTHING)
13839 {
13840 relation_mark_replica_identity(rel, stmt->identity_type, InvalidOid, true);
13841 return;
13842 }
13843 else if (stmt->identity_type == REPLICA_IDENTITY_INDEX)
13844 {
13845 /* fallthrough */ ;
13846 }
13847 else
13848 elog(ERROR, "unexpected identity type %u", stmt->identity_type);
13849
13850
13851 /* Check that the index exists */
13852 indexOid = get_relname_relid(stmt->name, rel->rd_rel->relnamespace);
13853 if (!OidIsValid(indexOid))
13854 ereport(ERROR,
13855 (errcode(ERRCODE_UNDEFINED_OBJECT),
13856 errmsg("index \"%s\" for table \"%s\" does not exist",
13857 stmt->name, RelationGetRelationName(rel))));
13858
13859 indexRel = index_open(indexOid, ShareLock);
13860
13861 /* Check that the index is on the relation we're altering. */
13862 if (indexRel->rd_index == NULL ||
13863 indexRel->rd_index->indrelid != RelationGetRelid(rel))
13864 ereport(ERROR,
13865 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
13866 errmsg("\"%s\" is not an index for table \"%s\"",
13867 RelationGetRelationName(indexRel),
13868 RelationGetRelationName(rel))));
13869 /* The AM must support uniqueness, and the index must in fact be unique. */
13870 if (!indexRel->rd_indam->amcanunique ||
13871 !indexRel->rd_index->indisunique)
13872 ereport(ERROR,
13873 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
13874 errmsg("cannot use non-unique index \"%s\" as replica identity",
13875 RelationGetRelationName(indexRel))));
13876 /* Deferred indexes are not guaranteed to be always unique. */
13877 if (!indexRel->rd_index->indimmediate)
13878 ereport(ERROR,
13879 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
13880 errmsg("cannot use non-immediate index \"%s\" as replica identity",
13881 RelationGetRelationName(indexRel))));
13882 /* Expression indexes aren't supported. */
13883 if (RelationGetIndexExpressions(indexRel) != NIL)
13884 ereport(ERROR,
13885 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
13886 errmsg("cannot use expression index \"%s\" as replica identity",
13887 RelationGetRelationName(indexRel))));
13888 /* Predicate indexes aren't supported. */
13889 if (RelationGetIndexPredicate(indexRel) != NIL)
13890 ereport(ERROR,
13891 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
13892 errmsg("cannot use partial index \"%s\" as replica identity",
13893 RelationGetRelationName(indexRel))));
13894 /* And neither are invalid indexes. */
13895 if (!indexRel->rd_index->indisvalid)
13896 ereport(ERROR,
13897 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
13898 errmsg("cannot use invalid index \"%s\" as replica identity",
13899 RelationGetRelationName(indexRel))));
13900
13901 /* Check index for nullable columns. */
13902 for (key = 0; key < IndexRelationGetNumberOfKeyAttributes(indexRel); key++)
13903 {
13904 int16 attno = indexRel->rd_index->indkey.values[key];
13905 Form_pg_attribute attr;
13906
13907 /*
13908 * Reject any other system columns. (Going forward, we'll disallow
13909 * indexes containing such columns in the first place, but they might
13910 * exist in older branches.)
13911 */
13912 if (attno <= 0)
13913 ereport(ERROR,
13914 (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
13915 errmsg("index \"%s\" cannot be used as replica identity because column %d is a system column",
13916 RelationGetRelationName(indexRel), attno)));
13917
13918 attr = TupleDescAttr(rel->rd_att, attno - 1);
13919 if (!attr->attnotnull)
13920 ereport(ERROR,
13921 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
13922 errmsg("index \"%s\" cannot be used as replica identity because column \"%s\" is nullable",
13923 RelationGetRelationName(indexRel),
13924 NameStr(attr->attname))));
13925 }
13926
13927 /* This index is suitable for use as a replica identity. Mark it. */
13928 relation_mark_replica_identity(rel, stmt->identity_type, indexOid, true);
13929
13930 index_close(indexRel, NoLock);
13931}
13932
13933/*
13934 * ALTER TABLE ENABLE/DISABLE ROW LEVEL SECURITY
13935 */
13936static void
13937ATExecEnableRowSecurity(Relation rel)
13938{
13939 Relation pg_class;
13940 Oid relid;
13941 HeapTuple tuple;
13942
13943 relid = RelationGetRelid(rel);
13944
13945 pg_class = table_open(RelationRelationId, RowExclusiveLock);
13946
13947 tuple = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(relid));
13948
13949 if (!HeapTupleIsValid(tuple))
13950 elog(ERROR, "cache lookup failed for relation %u", relid);
13951
13952 ((Form_pg_class) GETSTRUCT(tuple))->relrowsecurity = true;
13953 CatalogTupleUpdate(pg_class, &tuple->t_self, tuple);
13954
13955 table_close(pg_class, RowExclusiveLock);
13956 heap_freetuple(tuple);
13957}
13958
13959static void
13960ATExecDisableRowSecurity(Relation rel)
13961{
13962 Relation pg_class;
13963 Oid relid;
13964 HeapTuple tuple;
13965
13966 relid = RelationGetRelid(rel);
13967
13968 /* Pull the record for this relation and update it */
13969 pg_class = table_open(RelationRelationId, RowExclusiveLock);
13970
13971 tuple = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(relid));
13972
13973 if (!HeapTupleIsValid(tuple))
13974 elog(ERROR, "cache lookup failed for relation %u", relid);
13975
13976 ((Form_pg_class) GETSTRUCT(tuple))->relrowsecurity = false;
13977 CatalogTupleUpdate(pg_class, &tuple->t_self, tuple);
13978
13979 table_close(pg_class, RowExclusiveLock);
13980 heap_freetuple(tuple);
13981}
13982
13983/*
13984 * ALTER TABLE FORCE/NO FORCE ROW LEVEL SECURITY
13985 */
13986static void
13987ATExecForceNoForceRowSecurity(Relation rel, bool force_rls)
13988{
13989 Relation pg_class;
13990 Oid relid;
13991 HeapTuple tuple;
13992
13993 relid = RelationGetRelid(rel);
13994
13995 pg_class = table_open(RelationRelationId, RowExclusiveLock);
13996
13997 tuple = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(relid));
13998
13999 if (!HeapTupleIsValid(tuple))
14000 elog(ERROR, "cache lookup failed for relation %u", relid);
14001
14002 ((Form_pg_class) GETSTRUCT(tuple))->relforcerowsecurity = force_rls;
14003 CatalogTupleUpdate(pg_class, &tuple->t_self, tuple);
14004
14005 table_close(pg_class, RowExclusiveLock);
14006 heap_freetuple(tuple);
14007}
14008
14009/*
14010 * ALTER FOREIGN TABLE <name> OPTIONS (...)
14011 */
14012static void
14013ATExecGenericOptions(Relation rel, List *options)
14014{
14015 Relation ftrel;
14016 ForeignServer *server;
14017 ForeignDataWrapper *fdw;
14018 HeapTuple tuple;
14019 bool isnull;
14020 Datum repl_val[Natts_pg_foreign_table];
14021 bool repl_null[Natts_pg_foreign_table];
14022 bool repl_repl[Natts_pg_foreign_table];
14023 Datum datum;
14024 Form_pg_foreign_table tableform;
14025
14026 if (options == NIL)
14027 return;
14028
14029 ftrel = table_open(ForeignTableRelationId, RowExclusiveLock);
14030
14031 tuple = SearchSysCacheCopy1(FOREIGNTABLEREL, rel->rd_id);
14032 if (!HeapTupleIsValid(tuple))
14033 ereport(ERROR,
14034 (errcode(ERRCODE_UNDEFINED_OBJECT),
14035 errmsg("foreign table \"%s\" does not exist",
14036 RelationGetRelationName(rel))));
14037 tableform = (Form_pg_foreign_table) GETSTRUCT(tuple);
14038 server = GetForeignServer(tableform->ftserver);
14039 fdw = GetForeignDataWrapper(server->fdwid);
14040
14041 memset(repl_val, 0, sizeof(repl_val));
14042 memset(repl_null, false, sizeof(repl_null));
14043 memset(repl_repl, false, sizeof(repl_repl));
14044
14045 /* Extract the current options */
14046 datum = SysCacheGetAttr(FOREIGNTABLEREL,
14047 tuple,
14048 Anum_pg_foreign_table_ftoptions,
14049 &isnull);
14050 if (isnull)
14051 datum = PointerGetDatum(NULL);
14052
14053 /* Transform the options */
14054 datum = transformGenericOptions(ForeignTableRelationId,
14055 datum,
14056 options,
14057 fdw->fdwvalidator);
14058
14059 if (PointerIsValid(DatumGetPointer(datum)))
14060 repl_val[Anum_pg_foreign_table_ftoptions - 1] = datum;
14061 else
14062 repl_null[Anum_pg_foreign_table_ftoptions - 1] = true;
14063
14064 repl_repl[Anum_pg_foreign_table_ftoptions - 1] = true;
14065
14066 /* Everything looks good - update the tuple */
14067
14068 tuple = heap_modify_tuple(tuple, RelationGetDescr(ftrel),
14069 repl_val, repl_null, repl_repl);
14070
14071 CatalogTupleUpdate(ftrel, &tuple->t_self, tuple);
14072
14073 /*
14074 * Invalidate relcache so that all sessions will refresh any cached plans
14075 * that might depend on the old options.
14076 */
14077 CacheInvalidateRelcache(rel);
14078
14079 InvokeObjectPostAlterHook(ForeignTableRelationId,
14080 RelationGetRelid(rel), 0);
14081
14082 table_close(ftrel, RowExclusiveLock);
14083
14084 heap_freetuple(tuple);
14085}
14086
14087/*
14088 * Preparation phase for SET LOGGED/UNLOGGED
14089 *
14090 * This verifies that we're not trying to change a temp table. Also,
14091 * existing foreign key constraints are checked to avoid ending up with
14092 * permanent tables referencing unlogged tables.
14093 *
14094 * Return value is false if the operation is a no-op (in which case the
14095 * checks are skipped), otherwise true.
14096 */
14097static bool
14098ATPrepChangePersistence(Relation rel, bool toLogged)
14099{
14100 Relation pg_constraint;
14101 HeapTuple tuple;
14102 SysScanDesc scan;
14103 ScanKeyData skey[1];
14104
14105 /*
14106 * Disallow changing status for a temp table. Also verify whether we can
14107 * get away with doing nothing; in such cases we don't need to run the
14108 * checks below, either.
14109 */
14110 switch (rel->rd_rel->relpersistence)
14111 {
14112 case RELPERSISTENCE_TEMP:
14113 ereport(ERROR,
14114 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
14115 errmsg("cannot change logged status of table \"%s\" because it is temporary",
14116 RelationGetRelationName(rel)),
14117 errtable(rel)));
14118 break;
14119 case RELPERSISTENCE_PERMANENT:
14120 if (toLogged)
14121 /* nothing to do */
14122 return false;
14123 break;
14124 case RELPERSISTENCE_UNLOGGED:
14125 if (!toLogged)
14126 /* nothing to do */
14127 return false;
14128 break;
14129 }
14130
14131 /*
14132 * Check that the table is not part any publication when changing to
14133 * UNLOGGED as UNLOGGED tables can't be published.
14134 */
14135 if (!toLogged &&
14136 list_length(GetRelationPublications(RelationGetRelid(rel))) > 0)
14137 ereport(ERROR,
14138 (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
14139 errmsg("cannot change table \"%s\" to unlogged because it is part of a publication",
14140 RelationGetRelationName(rel)),
14141 errdetail("Unlogged relations cannot be replicated.")));
14142
14143 /*
14144 * Check existing foreign key constraints to preserve the invariant that
14145 * permanent tables cannot reference unlogged ones. Self-referencing
14146 * foreign keys can safely be ignored.
14147 */
14148 pg_constraint = table_open(ConstraintRelationId, AccessShareLock);
14149
14150 /*
14151 * Scan conrelid if changing to permanent, else confrelid. This also
14152 * determines whether a useful index exists.
14153 */
14154 ScanKeyInit(&skey[0],
14155 toLogged ? Anum_pg_constraint_conrelid :
14156 Anum_pg_constraint_confrelid,
14157 BTEqualStrategyNumber, F_OIDEQ,
14158 ObjectIdGetDatum(RelationGetRelid(rel)));
14159 scan = systable_beginscan(pg_constraint,
14160 toLogged ? ConstraintRelidTypidNameIndexId : InvalidOid,
14161 true, NULL, 1, skey);
14162
14163 while (HeapTupleIsValid(tuple = systable_getnext(scan)))
14164 {
14165 Form_pg_constraint con = (Form_pg_constraint) GETSTRUCT(tuple);
14166
14167 if (con->contype == CONSTRAINT_FOREIGN)
14168 {
14169 Oid foreignrelid;
14170 Relation foreignrel;
14171
14172 /* the opposite end of what we used as scankey */
14173 foreignrelid = toLogged ? con->confrelid : con->conrelid;
14174
14175 /* ignore if self-referencing */
14176 if (RelationGetRelid(rel) == foreignrelid)
14177 continue;
14178
14179 foreignrel = relation_open(foreignrelid, AccessShareLock);
14180
14181 if (toLogged)
14182 {
14183 if (foreignrel->rd_rel->relpersistence != RELPERSISTENCE_PERMANENT)
14184 ereport(ERROR,
14185 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
14186 errmsg("could not change table \"%s\" to logged because it references unlogged table \"%s\"",
14187 RelationGetRelationName(rel),
14188 RelationGetRelationName(foreignrel)),
14189 errtableconstraint(rel, NameStr(con->conname))));
14190 }
14191 else
14192 {
14193 if (foreignrel->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
14194 ereport(ERROR,
14195 (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
14196 errmsg("could not change table \"%s\" to unlogged because it references logged table \"%s\"",
14197 RelationGetRelationName(rel),
14198 RelationGetRelationName(foreignrel)),
14199 errtableconstraint(rel, NameStr(con->conname))));
14200 }
14201
14202 relation_close(foreignrel, AccessShareLock);
14203 }
14204 }
14205
14206 systable_endscan(scan);
14207
14208 table_close(pg_constraint, AccessShareLock);
14209
14210 return true;
14211}
14212
14213/*
14214 * Execute ALTER TABLE SET SCHEMA
14215 */
14216ObjectAddress
14217AlterTableNamespace(AlterObjectSchemaStmt *stmt, Oid *oldschema)
14218{
14219 Relation rel;
14220 Oid relid;
14221 Oid oldNspOid;
14222 Oid nspOid;
14223 RangeVar *newrv;
14224 ObjectAddresses *objsMoved;
14225 ObjectAddress myself;
14226
14227 relid = RangeVarGetRelidExtended(stmt->relation, AccessExclusiveLock,
14228 stmt->missing_ok ? RVR_MISSING_OK : 0,
14229 RangeVarCallbackForAlterRelation,
14230 (void *) stmt);
14231
14232 if (!OidIsValid(relid))
14233 {
14234 ereport(NOTICE,
14235 (errmsg("relation \"%s\" does not exist, skipping",
14236 stmt->relation->relname)));
14237 return InvalidObjectAddress;
14238 }
14239
14240 rel = relation_open(relid, NoLock);
14241
14242 oldNspOid = RelationGetNamespace(rel);
14243
14244 /* If it's an owned sequence, disallow moving it by itself. */
14245 if (rel->rd_rel->relkind == RELKIND_SEQUENCE)
14246 {
14247 Oid tableId;
14248 int32 colId;
14249
14250 if (sequenceIsOwned(relid, DEPENDENCY_AUTO, &tableId, &colId) ||
14251 sequenceIsOwned(relid, DEPENDENCY_INTERNAL, &tableId, &colId))
14252 ereport(ERROR,
14253 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
14254 errmsg("cannot move an owned sequence into another schema"),
14255 errdetail("Sequence \"%s\" is linked to table \"%s\".",
14256 RelationGetRelationName(rel),
14257 get_rel_name(tableId))));
14258 }
14259
14260 /* Get and lock schema OID and check its permissions. */
14261 newrv = makeRangeVar(stmt->newschema, RelationGetRelationName(rel), -1);
14262 nspOid = RangeVarGetAndCheckCreationNamespace(newrv, NoLock, NULL);
14263
14264 /* common checks on switching namespaces */
14265 CheckSetNamespace(oldNspOid, nspOid);
14266
14267 objsMoved = new_object_addresses();
14268 AlterTableNamespaceInternal(rel, oldNspOid, nspOid, objsMoved);
14269 free_object_addresses(objsMoved);
14270
14271 ObjectAddressSet(myself, RelationRelationId, relid);
14272
14273 if (oldschema)
14274 *oldschema = oldNspOid;
14275
14276 /* close rel, but keep lock until commit */
14277 relation_close(rel, NoLock);
14278
14279 return myself;
14280}
14281
14282/*
14283 * The guts of relocating a table or materialized view to another namespace:
14284 * besides moving the relation itself, its dependent objects are relocated to
14285 * the new schema.
14286 */
14287void
14288AlterTableNamespaceInternal(Relation rel, Oid oldNspOid, Oid nspOid,
14289 ObjectAddresses *objsMoved)
14290{
14291 Relation classRel;
14292
14293 Assert(objsMoved != NULL);
14294
14295 /* OK, modify the pg_class row and pg_depend entry */
14296 classRel = table_open(RelationRelationId, RowExclusiveLock);
14297
14298 AlterRelationNamespaceInternal(classRel, RelationGetRelid(rel), oldNspOid,
14299 nspOid, true, objsMoved);
14300
14301 /* Fix the table's row type too */
14302 AlterTypeNamespaceInternal(rel->rd_rel->reltype,
14303 nspOid, false, false, objsMoved);
14304
14305 /* Fix other dependent stuff */
14306 if (rel->rd_rel->relkind == RELKIND_RELATION ||
14307 rel->rd_rel->relkind == RELKIND_MATVIEW ||
14308 rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
14309 {
14310 AlterIndexNamespaces(classRel, rel, oldNspOid, nspOid, objsMoved);
14311 AlterSeqNamespaces(classRel, rel, oldNspOid, nspOid,
14312 objsMoved, AccessExclusiveLock);
14313 AlterConstraintNamespaces(RelationGetRelid(rel), oldNspOid, nspOid,
14314 false, objsMoved);
14315 }
14316
14317 table_close(classRel, RowExclusiveLock);
14318}
14319
14320/*
14321 * The guts of relocating a relation to another namespace: fix the pg_class
14322 * entry, and the pg_depend entry if any. Caller must already have
14323 * opened and write-locked pg_class.
14324 */
14325void
14326AlterRelationNamespaceInternal(Relation classRel, Oid relOid,
14327 Oid oldNspOid, Oid newNspOid,
14328 bool hasDependEntry,
14329 ObjectAddresses *objsMoved)
14330{
14331 HeapTuple classTup;
14332 Form_pg_class classForm;
14333 ObjectAddress thisobj;
14334 bool already_done = false;
14335
14336 classTup = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(relOid));
14337 if (!HeapTupleIsValid(classTup))
14338 elog(ERROR, "cache lookup failed for relation %u", relOid);
14339 classForm = (Form_pg_class) GETSTRUCT(classTup);
14340
14341 Assert(classForm->relnamespace == oldNspOid);
14342
14343 thisobj.classId = RelationRelationId;
14344 thisobj.objectId = relOid;
14345 thisobj.objectSubId = 0;
14346
14347 /*
14348 * If the object has already been moved, don't move it again. If it's
14349 * already in the right place, don't move it, but still fire the object
14350 * access hook.
14351 */
14352 already_done = object_address_present(&thisobj, objsMoved);
14353 if (!already_done && oldNspOid != newNspOid)
14354 {
14355 /* check for duplicate name (more friendly than unique-index failure) */
14356 if (get_relname_relid(NameStr(classForm->relname),
14357 newNspOid) != InvalidOid)
14358 ereport(ERROR,
14359 (errcode(ERRCODE_DUPLICATE_TABLE),
14360 errmsg("relation \"%s\" already exists in schema \"%s\"",
14361 NameStr(classForm->relname),
14362 get_namespace_name(newNspOid))));
14363
14364 /* classTup is a copy, so OK to scribble on */
14365 classForm->relnamespace = newNspOid;
14366
14367 CatalogTupleUpdate(classRel, &classTup->t_self, classTup);
14368
14369 /* Update dependency on schema if caller said so */
14370 if (hasDependEntry &&
14371 changeDependencyFor(RelationRelationId,
14372 relOid,
14373 NamespaceRelationId,
14374 oldNspOid,
14375 newNspOid) != 1)
14376 elog(ERROR, "failed to change schema dependency for relation \"%s\"",
14377 NameStr(classForm->relname));
14378 }
14379 if (!already_done)
14380 {
14381 add_exact_object_address(&thisobj, objsMoved);
14382
14383 InvokeObjectPostAlterHook(RelationRelationId, relOid, 0);
14384 }
14385
14386 heap_freetuple(classTup);
14387}
14388
14389/*
14390 * Move all indexes for the specified relation to another namespace.
14391 *
14392 * Note: we assume adequate permission checking was done by the caller,
14393 * and that the caller has a suitable lock on the owning relation.
14394 */
14395static void
14396AlterIndexNamespaces(Relation classRel, Relation rel,
14397 Oid oldNspOid, Oid newNspOid, ObjectAddresses *objsMoved)
14398{
14399 List *indexList;
14400 ListCell *l;
14401
14402 indexList = RelationGetIndexList(rel);
14403
14404 foreach(l, indexList)
14405 {
14406 Oid indexOid = lfirst_oid(l);
14407 ObjectAddress thisobj;
14408
14409 thisobj.classId = RelationRelationId;
14410 thisobj.objectId = indexOid;
14411 thisobj.objectSubId = 0;
14412
14413 /*
14414 * Note: currently, the index will not have its own dependency on the
14415 * namespace, so we don't need to do changeDependencyFor(). There's no
14416 * row type in pg_type, either.
14417 *
14418 * XXX this objsMoved test may be pointless -- surely we have a single
14419 * dependency link from a relation to each index?
14420 */
14421 if (!object_address_present(&thisobj, objsMoved))
14422 {
14423 AlterRelationNamespaceInternal(classRel, indexOid,
14424 oldNspOid, newNspOid,
14425 false, objsMoved);
14426 add_exact_object_address(&thisobj, objsMoved);
14427 }
14428 }
14429
14430 list_free(indexList);
14431}
14432
14433/*
14434 * Move all identity and SERIAL-column sequences of the specified relation to another
14435 * namespace.
14436 *
14437 * Note: we assume adequate permission checking was done by the caller,
14438 * and that the caller has a suitable lock on the owning relation.
14439 */
14440static void
14441AlterSeqNamespaces(Relation classRel, Relation rel,
14442 Oid oldNspOid, Oid newNspOid, ObjectAddresses *objsMoved,
14443 LOCKMODE lockmode)
14444{
14445 Relation depRel;
14446 SysScanDesc scan;
14447 ScanKeyData key[2];
14448 HeapTuple tup;
14449
14450 /*
14451 * SERIAL sequences are those having an auto dependency on one of the
14452 * table's columns (we don't care *which* column, exactly).
14453 */
14454 depRel = table_open(DependRelationId, AccessShareLock);
14455
14456 ScanKeyInit(&key[0],
14457 Anum_pg_depend_refclassid,
14458 BTEqualStrategyNumber, F_OIDEQ,
14459 ObjectIdGetDatum(RelationRelationId));
14460 ScanKeyInit(&key[1],
14461 Anum_pg_depend_refobjid,
14462 BTEqualStrategyNumber, F_OIDEQ,
14463 ObjectIdGetDatum(RelationGetRelid(rel)));
14464 /* we leave refobjsubid unspecified */
14465
14466 scan = systable_beginscan(depRel, DependReferenceIndexId, true,
14467 NULL, 2, key);
14468
14469 while (HeapTupleIsValid(tup = systable_getnext(scan)))
14470 {
14471 Form_pg_depend depForm = (Form_pg_depend) GETSTRUCT(tup);
14472 Relation seqRel;
14473
14474 /* skip dependencies other than auto dependencies on columns */
14475 if (depForm->refobjsubid == 0 ||
14476 depForm->classid != RelationRelationId ||
14477 depForm->objsubid != 0 ||
14478 !(depForm->deptype == DEPENDENCY_AUTO || depForm->deptype == DEPENDENCY_INTERNAL))
14479 continue;
14480
14481 /* Use relation_open just in case it's an index */
14482 seqRel = relation_open(depForm->objid, lockmode);
14483
14484 /* skip non-sequence relations */
14485 if (RelationGetForm(seqRel)->relkind != RELKIND_SEQUENCE)
14486 {
14487 /* No need to keep the lock */
14488 relation_close(seqRel, lockmode);
14489 continue;
14490 }
14491
14492 /* Fix the pg_class and pg_depend entries */
14493 AlterRelationNamespaceInternal(classRel, depForm->objid,
14494 oldNspOid, newNspOid,
14495 true, objsMoved);
14496
14497 /*
14498 * Sequences have entries in pg_type. We need to be careful to move
14499 * them to the new namespace, too.
14500 */
14501 AlterTypeNamespaceInternal(RelationGetForm(seqRel)->reltype,
14502 newNspOid, false, false, objsMoved);
14503
14504 /* Now we can close it. Keep the lock till end of transaction. */
14505 relation_close(seqRel, NoLock);
14506 }
14507
14508 systable_endscan(scan);
14509
14510 relation_close(depRel, AccessShareLock);
14511}
14512
14513
14514/*
14515 * This code supports
14516 * CREATE TEMP TABLE ... ON COMMIT { DROP | PRESERVE ROWS | DELETE ROWS }
14517 *
14518 * Because we only support this for TEMP tables, it's sufficient to remember
14519 * the state in a backend-local data structure.
14520 */
14521
14522/*
14523 * Register a newly-created relation's ON COMMIT action.
14524 */
14525void
14526register_on_commit_action(Oid relid, OnCommitAction action)
14527{
14528 OnCommitItem *oc;
14529 MemoryContext oldcxt;
14530
14531 /*
14532 * We needn't bother registering the relation unless there is an ON COMMIT
14533 * action we need to take.
14534 */
14535 if (action == ONCOMMIT_NOOP || action == ONCOMMIT_PRESERVE_ROWS)
14536 return;
14537
14538 oldcxt = MemoryContextSwitchTo(CacheMemoryContext);
14539
14540 oc = (OnCommitItem *) palloc(sizeof(OnCommitItem));
14541 oc->relid = relid;
14542 oc->oncommit = action;
14543 oc->creating_subid = GetCurrentSubTransactionId();
14544 oc->deleting_subid = InvalidSubTransactionId;
14545
14546 on_commits = lcons(oc, on_commits);
14547
14548 MemoryContextSwitchTo(oldcxt);
14549}
14550
14551/*
14552 * Unregister any ON COMMIT action when a relation is deleted.
14553 *
14554 * Actually, we only mark the OnCommitItem entry as to be deleted after commit.
14555 */
14556void
14557remove_on_commit_action(Oid relid)
14558{
14559 ListCell *l;
14560
14561 foreach(l, on_commits)
14562 {
14563 OnCommitItem *oc = (OnCommitItem *) lfirst(l);
14564
14565 if (oc->relid == relid)
14566 {
14567 oc->deleting_subid = GetCurrentSubTransactionId();
14568 break;
14569 }
14570 }
14571}
14572
14573/*
14574 * Perform ON COMMIT actions.
14575 *
14576 * This is invoked just before actually committing, since it's possible
14577 * to encounter errors.
14578 */
14579void
14580PreCommit_on_commit_actions(void)
14581{
14582 ListCell *l;
14583 List *oids_to_truncate = NIL;
14584 List *oids_to_drop = NIL;
14585
14586 foreach(l, on_commits)
14587 {
14588 OnCommitItem *oc = (OnCommitItem *) lfirst(l);
14589
14590 /* Ignore entry if already dropped in this xact */
14591 if (oc->deleting_subid != InvalidSubTransactionId)
14592 continue;
14593
14594 switch (oc->oncommit)
14595 {
14596 case ONCOMMIT_NOOP:
14597 case ONCOMMIT_PRESERVE_ROWS:
14598 /* Do nothing (there shouldn't be such entries, actually) */
14599 break;
14600 case ONCOMMIT_DELETE_ROWS:
14601
14602 /*
14603 * If this transaction hasn't accessed any temporary
14604 * relations, we can skip truncating ON COMMIT DELETE ROWS
14605 * tables, as they must still be empty.
14606 */
14607 if ((MyXactFlags & XACT_FLAGS_ACCESSEDTEMPNAMESPACE))
14608 oids_to_truncate = lappend_oid(oids_to_truncate, oc->relid);
14609 break;
14610 case ONCOMMIT_DROP:
14611 oids_to_drop = lappend_oid(oids_to_drop, oc->relid);
14612 break;
14613 }
14614 }
14615
14616 /*
14617 * Truncate relations before dropping so that all dependencies between
14618 * relations are removed after they are worked on. Doing it like this
14619 * might be a waste as it is possible that a relation being truncated will
14620 * be dropped anyway due to its parent being dropped, but this makes the
14621 * code more robust because of not having to re-check that the relation
14622 * exists at truncation time.
14623 */
14624 if (oids_to_truncate != NIL)
14625 heap_truncate(oids_to_truncate);
14626
14627 if (oids_to_drop != NIL)
14628 {
14629 ObjectAddresses *targetObjects = new_object_addresses();
14630 ListCell *l;
14631
14632 foreach(l, oids_to_drop)
14633 {
14634 ObjectAddress object;
14635
14636 object.classId = RelationRelationId;
14637 object.objectId = lfirst_oid(l);
14638 object.objectSubId = 0;
14639
14640 Assert(!object_address_present(&object, targetObjects));
14641
14642 add_exact_object_address(&object, targetObjects);
14643 }
14644
14645 /*
14646 * Since this is an automatic drop, rather than one directly initiated
14647 * by the user, we pass the PERFORM_DELETION_INTERNAL flag.
14648 */
14649 performMultipleDeletions(targetObjects, DROP_CASCADE,
14650 PERFORM_DELETION_INTERNAL | PERFORM_DELETION_QUIETLY);
14651
14652#ifdef USE_ASSERT_CHECKING
14653
14654 /*
14655 * Note that table deletion will call remove_on_commit_action, so the
14656 * entry should get marked as deleted.
14657 */
14658 foreach(l, on_commits)
14659 {
14660 OnCommitItem *oc = (OnCommitItem *) lfirst(l);
14661
14662 if (oc->oncommit != ONCOMMIT_DROP)
14663 continue;
14664
14665 Assert(oc->deleting_subid != InvalidSubTransactionId);
14666 }
14667#endif
14668 }
14669}
14670
14671/*
14672 * Post-commit or post-abort cleanup for ON COMMIT management.
14673 *
14674 * All we do here is remove no-longer-needed OnCommitItem entries.
14675 *
14676 * During commit, remove entries that were deleted during this transaction;
14677 * during abort, remove those created during this transaction.
14678 */
14679void
14680AtEOXact_on_commit_actions(bool isCommit)
14681{
14682 ListCell *cur_item;
14683 ListCell *prev_item;
14684
14685 prev_item = NULL;
14686 cur_item = list_head(on_commits);
14687
14688 while (cur_item != NULL)
14689 {
14690 OnCommitItem *oc = (OnCommitItem *) lfirst(cur_item);
14691
14692 if (isCommit ? oc->deleting_subid != InvalidSubTransactionId :
14693 oc->creating_subid != InvalidSubTransactionId)
14694 {
14695 /* cur_item must be removed */
14696 on_commits = list_delete_cell(on_commits, cur_item, prev_item);
14697 pfree(oc);
14698 if (prev_item)
14699 cur_item = lnext(prev_item);
14700 else
14701 cur_item = list_head(on_commits);
14702 }
14703 else
14704 {
14705 /* cur_item must be preserved */
14706 oc->creating_subid = InvalidSubTransactionId;
14707 oc->deleting_subid = InvalidSubTransactionId;
14708 prev_item = cur_item;
14709 cur_item = lnext(prev_item);
14710 }
14711 }
14712}
14713
14714/*
14715 * Post-subcommit or post-subabort cleanup for ON COMMIT management.
14716 *
14717 * During subabort, we can immediately remove entries created during this
14718 * subtransaction. During subcommit, just relabel entries marked during
14719 * this subtransaction as being the parent's responsibility.
14720 */
14721void
14722AtEOSubXact_on_commit_actions(bool isCommit, SubTransactionId mySubid,
14723 SubTransactionId parentSubid)
14724{
14725 ListCell *cur_item;
14726 ListCell *prev_item;
14727
14728 prev_item = NULL;
14729 cur_item = list_head(on_commits);
14730
14731 while (cur_item != NULL)
14732 {
14733 OnCommitItem *oc = (OnCommitItem *) lfirst(cur_item);
14734
14735 if (!isCommit && oc->creating_subid == mySubid)
14736 {
14737 /* cur_item must be removed */
14738 on_commits = list_delete_cell(on_commits, cur_item, prev_item);
14739 pfree(oc);
14740 if (prev_item)
14741 cur_item = lnext(prev_item);
14742 else
14743 cur_item = list_head(on_commits);
14744 }
14745 else
14746 {
14747 /* cur_item must be preserved */
14748 if (oc->creating_subid == mySubid)
14749 oc->creating_subid = parentSubid;
14750 if (oc->deleting_subid == mySubid)
14751 oc->deleting_subid = isCommit ? parentSubid : InvalidSubTransactionId;
14752 prev_item = cur_item;
14753 cur_item = lnext(prev_item);
14754 }
14755 }
14756}
14757
14758/*
14759 * This is intended as a callback for RangeVarGetRelidExtended(). It allows
14760 * the relation to be locked only if (1) it's a plain table, materialized
14761 * view, or TOAST table and (2) the current user is the owner (or the
14762 * superuser). This meets the permission-checking needs of CLUSTER, REINDEX
14763 * TABLE, and REFRESH MATERIALIZED VIEW; we expose it here so that it can be
14764 * used by all.
14765 */
14766void
14767RangeVarCallbackOwnsTable(const RangeVar *relation,
14768 Oid relId, Oid oldRelId, void *arg)
14769{
14770 char relkind;
14771
14772 /* Nothing to do if the relation was not found. */
14773 if (!OidIsValid(relId))
14774 return;
14775
14776 /*
14777 * If the relation does exist, check whether it's an index. But note that
14778 * the relation might have been dropped between the time we did the name
14779 * lookup and now. In that case, there's nothing to do.
14780 */
14781 relkind = get_rel_relkind(relId);
14782 if (!relkind)
14783 return;
14784 if (relkind != RELKIND_RELATION && relkind != RELKIND_TOASTVALUE &&
14785 relkind != RELKIND_MATVIEW && relkind != RELKIND_PARTITIONED_TABLE)
14786 ereport(ERROR,
14787 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
14788 errmsg("\"%s\" is not a table or materialized view", relation->relname)));
14789
14790 /* Check permissions */
14791 if (!pg_class_ownercheck(relId, GetUserId()))
14792 aclcheck_error(ACLCHECK_NOT_OWNER, get_relkind_objtype(get_rel_relkind(relId)), relation->relname);
14793}
14794
14795/*
14796 * Callback to RangeVarGetRelidExtended() for TRUNCATE processing.
14797 */
14798static void
14799RangeVarCallbackForTruncate(const RangeVar *relation,
14800 Oid relId, Oid oldRelId, void *arg)
14801{
14802 HeapTuple tuple;
14803
14804 /* Nothing to do if the relation was not found. */
14805 if (!OidIsValid(relId))
14806 return;
14807
14808 tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relId));
14809 if (!HeapTupleIsValid(tuple)) /* should not happen */
14810 elog(ERROR, "cache lookup failed for relation %u", relId);
14811
14812 truncate_check_rel(relId, (Form_pg_class) GETSTRUCT(tuple));
14813
14814 ReleaseSysCache(tuple);
14815}
14816
14817/*
14818 * Callback to RangeVarGetRelidExtended(), similar to
14819 * RangeVarCallbackOwnsTable() but without checks on the type of the relation.
14820 */
14821void
14822RangeVarCallbackOwnsRelation(const RangeVar *relation,
14823 Oid relId, Oid oldRelId, void *arg)
14824{
14825 HeapTuple tuple;
14826
14827 /* Nothing to do if the relation was not found. */
14828 if (!OidIsValid(relId))
14829 return;
14830
14831 tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relId));
14832 if (!HeapTupleIsValid(tuple)) /* should not happen */
14833 elog(ERROR, "cache lookup failed for relation %u", relId);
14834
14835 if (!pg_class_ownercheck(relId, GetUserId()))
14836 aclcheck_error(ACLCHECK_NOT_OWNER, get_relkind_objtype(get_rel_relkind(relId)),
14837 relation->relname);
14838
14839 if (!allowSystemTableMods &&
14840 IsSystemClass(relId, (Form_pg_class) GETSTRUCT(tuple)))
14841 ereport(ERROR,
14842 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
14843 errmsg("permission denied: \"%s\" is a system catalog",
14844 relation->relname)));
14845
14846 ReleaseSysCache(tuple);
14847}
14848
14849/*
14850 * Common RangeVarGetRelid callback for rename, set schema, and alter table
14851 * processing.
14852 */
14853static void
14854RangeVarCallbackForAlterRelation(const RangeVar *rv, Oid relid, Oid oldrelid,
14855 void *arg)
14856{
14857 Node *stmt = (Node *) arg;
14858 ObjectType reltype;
14859 HeapTuple tuple;
14860 Form_pg_class classform;
14861 AclResult aclresult;
14862 char relkind;
14863
14864 tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relid));
14865 if (!HeapTupleIsValid(tuple))
14866 return; /* concurrently dropped */
14867 classform = (Form_pg_class) GETSTRUCT(tuple);
14868 relkind = classform->relkind;
14869
14870 /* Must own relation. */
14871 if (!pg_class_ownercheck(relid, GetUserId()))
14872 aclcheck_error(ACLCHECK_NOT_OWNER, get_relkind_objtype(get_rel_relkind(relid)), rv->relname);
14873
14874 /* No system table modifications unless explicitly allowed. */
14875 if (!allowSystemTableMods && IsSystemClass(relid, classform))
14876 ereport(ERROR,
14877 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
14878 errmsg("permission denied: \"%s\" is a system catalog",
14879 rv->relname)));
14880
14881 /*
14882 * Extract the specified relation type from the statement parse tree.
14883 *
14884 * Also, for ALTER .. RENAME, check permissions: the user must (still)
14885 * have CREATE rights on the containing namespace.
14886 */
14887 if (IsA(stmt, RenameStmt))
14888 {
14889 aclresult = pg_namespace_aclcheck(classform->relnamespace,
14890 GetUserId(), ACL_CREATE);
14891 if (aclresult != ACLCHECK_OK)
14892 aclcheck_error(aclresult, OBJECT_SCHEMA,
14893 get_namespace_name(classform->relnamespace));
14894 reltype = ((RenameStmt *) stmt)->renameType;
14895 }
14896 else if (IsA(stmt, AlterObjectSchemaStmt))
14897 reltype = ((AlterObjectSchemaStmt *) stmt)->objectType;
14898
14899 else if (IsA(stmt, AlterTableStmt))
14900 reltype = ((AlterTableStmt *) stmt)->relkind;
14901 else
14902 {
14903 elog(ERROR, "unrecognized node type: %d", (int) nodeTag(stmt));
14904 reltype = OBJECT_TABLE; /* placate compiler */
14905 }
14906
14907 /*
14908 * For compatibility with prior releases, we allow ALTER TABLE to be used
14909 * with most other types of relations (but not composite types). We allow
14910 * similar flexibility for ALTER INDEX in the case of RENAME, but not
14911 * otherwise. Otherwise, the user must select the correct form of the
14912 * command for the relation at issue.
14913 */
14914 if (reltype == OBJECT_SEQUENCE && relkind != RELKIND_SEQUENCE)
14915 ereport(ERROR,
14916 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
14917 errmsg("\"%s\" is not a sequence", rv->relname)));
14918
14919 if (reltype == OBJECT_VIEW && relkind != RELKIND_VIEW)
14920 ereport(ERROR,
14921 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
14922 errmsg("\"%s\" is not a view", rv->relname)));
14923
14924 if (reltype == OBJECT_MATVIEW && relkind != RELKIND_MATVIEW)
14925 ereport(ERROR,
14926 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
14927 errmsg("\"%s\" is not a materialized view", rv->relname)));
14928
14929 if (reltype == OBJECT_FOREIGN_TABLE && relkind != RELKIND_FOREIGN_TABLE)
14930 ereport(ERROR,
14931 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
14932 errmsg("\"%s\" is not a foreign table", rv->relname)));
14933
14934 if (reltype == OBJECT_TYPE && relkind != RELKIND_COMPOSITE_TYPE)
14935 ereport(ERROR,
14936 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
14937 errmsg("\"%s\" is not a composite type", rv->relname)));
14938
14939 if (reltype == OBJECT_INDEX && relkind != RELKIND_INDEX &&
14940 relkind != RELKIND_PARTITIONED_INDEX
14941 && !IsA(stmt, RenameStmt))
14942 ereport(ERROR,
14943 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
14944 errmsg("\"%s\" is not an index", rv->relname)));
14945
14946 /*
14947 * Don't allow ALTER TABLE on composite types. We want people to use ALTER
14948 * TYPE for that.
14949 */
14950 if (reltype != OBJECT_TYPE && relkind == RELKIND_COMPOSITE_TYPE)
14951 ereport(ERROR,
14952 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
14953 errmsg("\"%s\" is a composite type", rv->relname),
14954 errhint("Use ALTER TYPE instead.")));
14955
14956 /*
14957 * Don't allow ALTER TABLE .. SET SCHEMA on relations that can't be moved
14958 * to a different schema, such as indexes and TOAST tables.
14959 */
14960 if (IsA(stmt, AlterObjectSchemaStmt) &&
14961 relkind != RELKIND_RELATION &&
14962 relkind != RELKIND_VIEW &&
14963 relkind != RELKIND_MATVIEW &&
14964 relkind != RELKIND_SEQUENCE &&
14965 relkind != RELKIND_FOREIGN_TABLE &&
14966 relkind != RELKIND_PARTITIONED_TABLE)
14967 ereport(ERROR,
14968 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
14969 errmsg("\"%s\" is not a table, view, materialized view, sequence, or foreign table",
14970 rv->relname)));
14971
14972 ReleaseSysCache(tuple);
14973}
14974
14975/*
14976 * Transform any expressions present in the partition key
14977 *
14978 * Returns a transformed PartitionSpec, as well as the strategy code
14979 */
14980static PartitionSpec *
14981transformPartitionSpec(Relation rel, PartitionSpec *partspec, char *strategy)
14982{
14983 PartitionSpec *newspec;
14984 ParseState *pstate;
14985 RangeTblEntry *rte;
14986 ListCell *l;
14987
14988 newspec = makeNode(PartitionSpec);
14989
14990 newspec->strategy = partspec->strategy;
14991 newspec->partParams = NIL;
14992 newspec->location = partspec->location;
14993
14994 /* Parse partitioning strategy name */
14995 if (pg_strcasecmp(partspec->strategy, "hash") == 0)
14996 *strategy = PARTITION_STRATEGY_HASH;
14997 else if (pg_strcasecmp(partspec->strategy, "list") == 0)
14998 *strategy = PARTITION_STRATEGY_LIST;
14999 else if (pg_strcasecmp(partspec->strategy, "range") == 0)
15000 *strategy = PARTITION_STRATEGY_RANGE;
15001 else
15002 ereport(ERROR,
15003 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
15004 errmsg("unrecognized partitioning strategy \"%s\"",
15005 partspec->strategy)));
15006
15007 /* Check valid number of columns for strategy */
15008 if (*strategy == PARTITION_STRATEGY_LIST &&
15009 list_length(partspec->partParams) != 1)
15010 ereport(ERROR,
15011 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
15012 errmsg("cannot use \"list\" partition strategy with more than one column")));
15013
15014 /*
15015 * Create a dummy ParseState and insert the target relation as its sole
15016 * rangetable entry. We need a ParseState for transformExpr.
15017 */
15018 pstate = make_parsestate(NULL);
15019 rte = addRangeTableEntryForRelation(pstate, rel, AccessShareLock,
15020 NULL, false, true);
15021 addRTEtoQuery(pstate, rte, true, true, true);
15022
15023 /* take care of any partition expressions */
15024 foreach(l, partspec->partParams)
15025 {
15026 PartitionElem *pelem = castNode(PartitionElem, lfirst(l));
15027
15028 if (pelem->expr)
15029 {
15030 /* Copy, to avoid scribbling on the input */
15031 pelem = copyObject(pelem);
15032
15033 /* Now do parse transformation of the expression */
15034 pelem->expr = transformExpr(pstate, pelem->expr,
15035 EXPR_KIND_PARTITION_EXPRESSION);
15036
15037 /* we have to fix its collations too */
15038 assign_expr_collations(pstate, pelem->expr);
15039 }
15040
15041 newspec->partParams = lappend(newspec->partParams, pelem);
15042 }
15043
15044 return newspec;
15045}
15046
15047/*
15048 * Compute per-partition-column information from a list of PartitionElems.
15049 * Expressions in the PartitionElems must be parse-analyzed already.
15050 */
15051static void
15052ComputePartitionAttrs(ParseState *pstate, Relation rel, List *partParams, AttrNumber *partattrs,
15053 List **partexprs, Oid *partopclass, Oid *partcollation,
15054 char strategy)
15055{
15056 int attn;
15057 ListCell *lc;
15058 Oid am_oid;
15059
15060 attn = 0;
15061 foreach(lc, partParams)
15062 {
15063 PartitionElem *pelem = castNode(PartitionElem, lfirst(lc));
15064 Oid atttype;
15065 Oid attcollation;
15066
15067 if (pelem->name != NULL)
15068 {
15069 /* Simple attribute reference */
15070 HeapTuple atttuple;
15071 Form_pg_attribute attform;
15072
15073 atttuple = SearchSysCacheAttName(RelationGetRelid(rel),
15074 pelem->name);
15075 if (!HeapTupleIsValid(atttuple))
15076 ereport(ERROR,
15077 (errcode(ERRCODE_UNDEFINED_COLUMN),
15078 errmsg("column \"%s\" named in partition key does not exist",
15079 pelem->name),
15080 parser_errposition(pstate, pelem->location)));
15081 attform = (Form_pg_attribute) GETSTRUCT(atttuple);
15082
15083 if (attform->attnum <= 0)
15084 ereport(ERROR,
15085 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
15086 errmsg("cannot use system column \"%s\" in partition key",
15087 pelem->name),
15088 parser_errposition(pstate, pelem->location)));
15089
15090 /*
15091 * Generated columns cannot work: They are computed after BEFORE
15092 * triggers, but partition routing is done before all triggers.
15093 */
15094 if (attform->attgenerated)
15095 ereport(ERROR,
15096 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
15097 errmsg("cannot use generated column in partition key"),
15098 errdetail("Column \"%s\" is a generated column.",
15099 pelem->name),
15100 parser_errposition(pstate, pelem->location)));
15101
15102 partattrs[attn] = attform->attnum;
15103 atttype = attform->atttypid;
15104 attcollation = attform->attcollation;
15105 ReleaseSysCache(atttuple);
15106 }
15107 else
15108 {
15109 /* Expression */
15110 Node *expr = pelem->expr;
15111
15112 Assert(expr != NULL);
15113 atttype = exprType(expr);
15114 attcollation = exprCollation(expr);
15115
15116 /*
15117 * Strip any top-level COLLATE clause. This ensures that we treat
15118 * "x COLLATE y" and "(x COLLATE y)" alike.
15119 */
15120 while (IsA(expr, CollateExpr))
15121 expr = (Node *) ((CollateExpr *) expr)->arg;
15122
15123 if (IsA(expr, Var) &&
15124 ((Var *) expr)->varattno > 0)
15125 {
15126 /*
15127 * User wrote "(column)" or "(column COLLATE something)".
15128 * Treat it like simple attribute anyway.
15129 */
15130 partattrs[attn] = ((Var *) expr)->varattno;
15131 }
15132 else
15133 {
15134 Bitmapset *expr_attrs = NULL;
15135 int i;
15136
15137 partattrs[attn] = 0; /* marks the column as expression */
15138 *partexprs = lappend(*partexprs, expr);
15139
15140 /*
15141 * Try to simplify the expression before checking for
15142 * mutability. The main practical value of doing it in this
15143 * order is that an inline-able SQL-language function will be
15144 * accepted if its expansion is immutable, whether or not the
15145 * function itself is marked immutable.
15146 *
15147 * Note that expression_planner does not change the passed in
15148 * expression destructively and we have already saved the
15149 * expression to be stored into the catalog above.
15150 */
15151 expr = (Node *) expression_planner((Expr *) expr);
15152
15153 /*
15154 * Partition expression cannot contain mutable functions,
15155 * because a given row must always map to the same partition
15156 * as long as there is no change in the partition boundary
15157 * structure.
15158 */
15159 if (contain_mutable_functions(expr))
15160 ereport(ERROR,
15161 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
15162 errmsg("functions in partition key expression must be marked IMMUTABLE")));
15163
15164 /*
15165 * transformPartitionSpec() should have already rejected
15166 * subqueries, aggregates, window functions, and SRFs, based
15167 * on the EXPR_KIND_ for partition expressions.
15168 */
15169
15170 /*
15171 * Cannot have expressions containing whole-row references or
15172 * system column references.
15173 */
15174 pull_varattnos(expr, 1, &expr_attrs);
15175 if (bms_is_member(0 - FirstLowInvalidHeapAttributeNumber,
15176 expr_attrs))
15177 ereport(ERROR,
15178 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
15179 errmsg("partition key expressions cannot contain whole-row references")));
15180 for (i = FirstLowInvalidHeapAttributeNumber; i < 0; i++)
15181 {
15182 if (bms_is_member(i - FirstLowInvalidHeapAttributeNumber,
15183 expr_attrs))
15184 ereport(ERROR,
15185 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
15186 errmsg("partition key expressions cannot contain system column references")));
15187 }
15188
15189 /*
15190 * Generated columns cannot work: They are computed after
15191 * BEFORE triggers, but partition routing is done before all
15192 * triggers.
15193 */
15194 i = -1;
15195 while ((i = bms_next_member(expr_attrs, i)) >= 0)
15196 {
15197 AttrNumber attno = i + FirstLowInvalidHeapAttributeNumber;
15198
15199 if (TupleDescAttr(RelationGetDescr(rel), attno - 1)->attgenerated)
15200 ereport(ERROR,
15201 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
15202 errmsg("cannot use generated column in partition key"),
15203 errdetail("Column \"%s\" is a generated column.",
15204 get_attname(RelationGetRelid(rel), attno, false)),
15205 parser_errposition(pstate, pelem->location)));
15206 }
15207
15208 /*
15209 * While it is not exactly *wrong* for a partition expression
15210 * to be a constant, it seems better to reject such keys.
15211 */
15212 if (IsA(expr, Const))
15213 ereport(ERROR,
15214 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
15215 errmsg("cannot use constant expression as partition key")));
15216 }
15217 }
15218
15219 /*
15220 * Apply collation override if any
15221 */
15222 if (pelem->collation)
15223 attcollation = get_collation_oid(pelem->collation, false);
15224
15225 /*
15226 * Check we have a collation iff it's a collatable type. The only
15227 * expected failures here are (1) COLLATE applied to a noncollatable
15228 * type, or (2) partition expression had an unresolved collation. But
15229 * we might as well code this to be a complete consistency check.
15230 */
15231 if (type_is_collatable(atttype))
15232 {
15233 if (!OidIsValid(attcollation))
15234 ereport(ERROR,
15235 (errcode(ERRCODE_INDETERMINATE_COLLATION),
15236 errmsg("could not determine which collation to use for partition expression"),
15237 errhint("Use the COLLATE clause to set the collation explicitly.")));
15238 }
15239 else
15240 {
15241 if (OidIsValid(attcollation))
15242 ereport(ERROR,
15243 (errcode(ERRCODE_DATATYPE_MISMATCH),
15244 errmsg("collations are not supported by type %s",
15245 format_type_be(atttype))));
15246 }
15247
15248 partcollation[attn] = attcollation;
15249
15250 /*
15251 * Identify the appropriate operator class. For list and range
15252 * partitioning, we use a btree operator class; hash partitioning uses
15253 * a hash operator class.
15254 */
15255 if (strategy == PARTITION_STRATEGY_HASH)
15256 am_oid = HASH_AM_OID;
15257 else
15258 am_oid = BTREE_AM_OID;
15259
15260 if (!pelem->opclass)
15261 {
15262 partopclass[attn] = GetDefaultOpClass(atttype, am_oid);
15263
15264 if (!OidIsValid(partopclass[attn]))
15265 {
15266 if (strategy == PARTITION_STRATEGY_HASH)
15267 ereport(ERROR,
15268 (errcode(ERRCODE_UNDEFINED_OBJECT),
15269 errmsg("data type %s has no default operator class for access method \"%s\"",
15270 format_type_be(atttype), "hash"),
15271 errhint("You must specify a hash operator class or define a default hash operator class for the data type.")));
15272 else
15273 ereport(ERROR,
15274 (errcode(ERRCODE_UNDEFINED_OBJECT),
15275 errmsg("data type %s has no default operator class for access method \"%s\"",
15276 format_type_be(atttype), "btree"),
15277 errhint("You must specify a btree operator class or define a default btree operator class for the data type.")));
15278
15279 }
15280 }
15281 else
15282 partopclass[attn] = ResolveOpClass(pelem->opclass,
15283 atttype,
15284 am_oid == HASH_AM_OID ? "hash" : "btree",
15285 am_oid);
15286
15287 attn++;
15288 }
15289}
15290
15291/*
15292 * PartConstraintImpliedByRelConstraint
15293 * Do scanrel's existing constraints imply the partition constraint?
15294 *
15295 * "Existing constraints" include its check constraints and column-level
15296 * NOT NULL constraints. partConstraint describes the partition constraint,
15297 * in implicit-AND form.
15298 */
15299bool
15300PartConstraintImpliedByRelConstraint(Relation scanrel,
15301 List *partConstraint)
15302{
15303 List *existConstraint = NIL;
15304 TupleConstr *constr = RelationGetDescr(scanrel)->constr;
15305 int i;
15306
15307 if (constr && constr->has_not_null)
15308 {
15309 int natts = scanrel->rd_att->natts;
15310
15311 for (i = 1; i <= natts; i++)
15312 {
15313 Form_pg_attribute att = TupleDescAttr(scanrel->rd_att, i - 1);
15314
15315 if (att->attnotnull && !att->attisdropped)
15316 {
15317 NullTest *ntest = makeNode(NullTest);
15318
15319 ntest->arg = (Expr *) makeVar(1,
15320 i,
15321 att->atttypid,
15322 att->atttypmod,
15323 att->attcollation,
15324 0);
15325 ntest->nulltesttype = IS_NOT_NULL;
15326
15327 /*
15328 * argisrow=false is correct even for a composite column,
15329 * because attnotnull does not represent a SQL-spec IS NOT
15330 * NULL test in such a case, just IS DISTINCT FROM NULL.
15331 */
15332 ntest->argisrow = false;
15333 ntest->location = -1;
15334 existConstraint = lappend(existConstraint, ntest);
15335 }
15336 }
15337 }
15338
15339 return ConstraintImpliedByRelConstraint(scanrel, partConstraint, existConstraint);
15340}
15341
15342/*
15343 * ConstraintImpliedByRelConstraint
15344 * Do scanrel's existing constraints imply the given constraint?
15345 *
15346 * testConstraint is the constraint to validate. provenConstraint is a
15347 * caller-provided list of conditions which this function may assume
15348 * to be true. Both provenConstraint and testConstraint must be in
15349 * implicit-AND form, must only contain immutable clauses, and must
15350 * contain only Vars with varno = 1.
15351 */
15352bool
15353ConstraintImpliedByRelConstraint(Relation scanrel, List *testConstraint, List *provenConstraint)
15354{
15355 List *existConstraint = list_copy(provenConstraint);
15356 TupleConstr *constr = RelationGetDescr(scanrel)->constr;
15357 int num_check,
15358 i;
15359
15360 num_check = (constr != NULL) ? constr->num_check : 0;
15361 for (i = 0; i < num_check; i++)
15362 {
15363 Node *cexpr;
15364
15365 /*
15366 * If this constraint hasn't been fully validated yet, we must ignore
15367 * it here.
15368 */
15369 if (!constr->check[i].ccvalid)
15370 continue;
15371
15372 cexpr = stringToNode(constr->check[i].ccbin);
15373
15374 /*
15375 * Run each expression through const-simplification and
15376 * canonicalization. It is necessary, because we will be comparing it
15377 * to similarly-processed partition constraint expressions, and may
15378 * fail to detect valid matches without this.
15379 */
15380 cexpr = eval_const_expressions(NULL, cexpr);
15381 cexpr = (Node *) canonicalize_qual((Expr *) cexpr, true);
15382
15383 existConstraint = list_concat(existConstraint,
15384 make_ands_implicit((Expr *) cexpr));
15385 }
15386
15387 /*
15388 * Try to make the proof. Since we are comparing CHECK constraints, we
15389 * need to use weak implication, i.e., we assume existConstraint is
15390 * not-false and try to prove the same for testConstraint.
15391 *
15392 * Note that predicate_implied_by assumes its first argument is known
15393 * immutable. That should always be true for both NOT NULL and partition
15394 * constraints, so we don't test it here.
15395 */
15396 return predicate_implied_by(testConstraint, existConstraint, true);
15397}
15398
15399/*
15400 * QueuePartitionConstraintValidation
15401 *
15402 * Add an entry to wqueue to have the given partition constraint validated by
15403 * Phase 3, for the given relation, and all its children.
15404 *
15405 * We first verify whether the given constraint is implied by pre-existing
15406 * relation constraints; if it is, there's no need to scan the table to
15407 * validate, so don't queue in that case.
15408 */
15409static void
15410QueuePartitionConstraintValidation(List **wqueue, Relation scanrel,
15411 List *partConstraint,
15412 bool validate_default)
15413{
15414 /*
15415 * Based on the table's existing constraints, determine whether or not we
15416 * may skip scanning the table.
15417 */
15418 if (PartConstraintImpliedByRelConstraint(scanrel, partConstraint))
15419 {
15420 if (!validate_default)
15421 ereport(DEBUG1,
15422 (errmsg("partition constraint for table \"%s\" is implied by existing constraints",
15423 RelationGetRelationName(scanrel))));
15424 else
15425 ereport(DEBUG1,
15426 (errmsg("updated partition constraint for default partition \"%s\" is implied by existing constraints",
15427 RelationGetRelationName(scanrel))));
15428 return;
15429 }
15430
15431 /*
15432 * Constraints proved insufficient. For plain relations, queue a
15433 * validation item now; for partitioned tables, recurse to process each
15434 * partition.
15435 */
15436 if (scanrel->rd_rel->relkind == RELKIND_RELATION)
15437 {
15438 AlteredTableInfo *tab;
15439
15440 /* Grab a work queue entry. */
15441 tab = ATGetQueueEntry(wqueue, scanrel);
15442 Assert(tab->partition_constraint == NULL);
15443 tab->partition_constraint = (Expr *) linitial(partConstraint);
15444 tab->validate_default = validate_default;
15445 }
15446 else if (scanrel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
15447 {
15448 PartitionDesc partdesc = RelationGetPartitionDesc(scanrel);
15449 int i;
15450
15451 for (i = 0; i < partdesc->nparts; i++)
15452 {
15453 Relation part_rel;
15454 bool found_whole_row;
15455 List *thisPartConstraint;
15456
15457 /*
15458 * This is the minimum lock we need to prevent deadlocks.
15459 */
15460 part_rel = table_open(partdesc->oids[i], AccessExclusiveLock);
15461
15462 /*
15463 * Adjust the constraint for scanrel so that it matches this
15464 * partition's attribute numbers.
15465 */
15466 thisPartConstraint =
15467 map_partition_varattnos(partConstraint, 1,
15468 part_rel, scanrel, &found_whole_row);
15469 /* There can never be a whole-row reference here */
15470 if (found_whole_row)
15471 elog(ERROR, "unexpected whole-row reference found in partition constraint");
15472
15473 QueuePartitionConstraintValidation(wqueue, part_rel,
15474 thisPartConstraint,
15475 validate_default);
15476 table_close(part_rel, NoLock); /* keep lock till commit */
15477 }
15478 }
15479}
15480
15481/*
15482 * ALTER TABLE <name> ATTACH PARTITION <partition-name> FOR VALUES
15483 *
15484 * Return the address of the newly attached partition.
15485 */
15486static ObjectAddress
15487ATExecAttachPartition(List **wqueue, Relation rel, PartitionCmd *cmd)
15488{
15489 Relation attachrel,
15490 catalog;
15491 List *attachrel_children;
15492 List *partConstraint;
15493 SysScanDesc scan;
15494 ScanKeyData skey;
15495 AttrNumber attno;
15496 int natts;
15497 TupleDesc tupleDesc;
15498 ObjectAddress address;
15499 const char *trigger_name;
15500 bool found_whole_row;
15501 Oid defaultPartOid;
15502 List *partBoundConstraint;
15503
15504 /*
15505 * We must lock the default partition if one exists, because attaching a
15506 * new partition will change its partition constraint.
15507 */
15508 defaultPartOid =
15509 get_default_oid_from_partdesc(RelationGetPartitionDesc(rel));
15510 if (OidIsValid(defaultPartOid))
15511 LockRelationOid(defaultPartOid, AccessExclusiveLock);
15512
15513 attachrel = table_openrv(cmd->name, AccessExclusiveLock);
15514
15515 /*
15516 * XXX I think it'd be a good idea to grab locks on all tables referenced
15517 * by FKs at this point also.
15518 */
15519
15520 /*
15521 * Must be owner of both parent and source table -- parent was checked by
15522 * ATSimplePermissions call in ATPrepCmd
15523 */
15524 ATSimplePermissions(attachrel, ATT_TABLE | ATT_FOREIGN_TABLE);
15525
15526 /* A partition can only have one parent */
15527 if (attachrel->rd_rel->relispartition)
15528 ereport(ERROR,
15529 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
15530 errmsg("\"%s\" is already a partition",
15531 RelationGetRelationName(attachrel))));
15532
15533 if (OidIsValid(attachrel->rd_rel->reloftype))
15534 ereport(ERROR,
15535 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
15536 errmsg("cannot attach a typed table as partition")));
15537
15538 /*
15539 * Table being attached should not already be part of inheritance; either
15540 * as a child table...
15541 */
15542 catalog = table_open(InheritsRelationId, AccessShareLock);
15543 ScanKeyInit(&skey,
15544 Anum_pg_inherits_inhrelid,
15545 BTEqualStrategyNumber, F_OIDEQ,
15546 ObjectIdGetDatum(RelationGetRelid(attachrel)));
15547 scan = systable_beginscan(catalog, InheritsRelidSeqnoIndexId, true,
15548 NULL, 1, &skey);
15549 if (HeapTupleIsValid(systable_getnext(scan)))
15550 ereport(ERROR,
15551 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
15552 errmsg("cannot attach inheritance child as partition")));
15553 systable_endscan(scan);
15554
15555 /* ...or as a parent table (except the case when it is partitioned) */
15556 ScanKeyInit(&skey,
15557 Anum_pg_inherits_inhparent,
15558 BTEqualStrategyNumber, F_OIDEQ,
15559 ObjectIdGetDatum(RelationGetRelid(attachrel)));
15560 scan = systable_beginscan(catalog, InheritsParentIndexId, true, NULL,
15561 1, &skey);
15562 if (HeapTupleIsValid(systable_getnext(scan)) &&
15563 attachrel->rd_rel->relkind == RELKIND_RELATION)
15564 ereport(ERROR,
15565 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
15566 errmsg("cannot attach inheritance parent as partition")));
15567 systable_endscan(scan);
15568 table_close(catalog, AccessShareLock);
15569
15570 /*
15571 * Prevent circularity by seeing if rel is a partition of attachrel. (In
15572 * particular, this disallows making a rel a partition of itself.)
15573 *
15574 * We do that by checking if rel is a member of the list of attachrel's
15575 * partitions provided the latter is partitioned at all. We want to avoid
15576 * having to construct this list again, so we request the strongest lock
15577 * on all partitions. We need the strongest lock, because we may decide
15578 * to scan them if we find out that the table being attached (or its leaf
15579 * partitions) may contain rows that violate the partition constraint. If
15580 * the table has a constraint that would prevent such rows, which by
15581 * definition is present in all the partitions, we need not scan the
15582 * table, nor its partitions. But we cannot risk a deadlock by taking a
15583 * weaker lock now and the stronger one only when needed.
15584 */
15585 attachrel_children = find_all_inheritors(RelationGetRelid(attachrel),
15586 AccessExclusiveLock, NULL);
15587 if (list_member_oid(attachrel_children, RelationGetRelid(rel)))
15588 ereport(ERROR,
15589 (errcode(ERRCODE_DUPLICATE_TABLE),
15590 errmsg("circular inheritance not allowed"),
15591 errdetail("\"%s\" is already a child of \"%s\".",
15592 RelationGetRelationName(rel),
15593 RelationGetRelationName(attachrel))));
15594
15595 /* If the parent is permanent, so must be all of its partitions. */
15596 if (rel->rd_rel->relpersistence != RELPERSISTENCE_TEMP &&
15597 attachrel->rd_rel->relpersistence == RELPERSISTENCE_TEMP)
15598 ereport(ERROR,
15599 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
15600 errmsg("cannot attach a temporary relation as partition of permanent relation \"%s\"",
15601 RelationGetRelationName(rel))));
15602
15603 /* Temp parent cannot have a partition that is itself not a temp */
15604 if (rel->rd_rel->relpersistence == RELPERSISTENCE_TEMP &&
15605 attachrel->rd_rel->relpersistence != RELPERSISTENCE_TEMP)
15606 ereport(ERROR,
15607 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
15608 errmsg("cannot attach a permanent relation as partition of temporary relation \"%s\"",
15609 RelationGetRelationName(rel))));
15610
15611 /* If the parent is temp, it must belong to this session */
15612 if (rel->rd_rel->relpersistence == RELPERSISTENCE_TEMP &&
15613 !rel->rd_islocaltemp)
15614 ereport(ERROR,
15615 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
15616 errmsg("cannot attach as partition of temporary relation of another session")));
15617
15618 /* Ditto for the partition */
15619 if (attachrel->rd_rel->relpersistence == RELPERSISTENCE_TEMP &&
15620 !attachrel->rd_islocaltemp)
15621 ereport(ERROR,
15622 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
15623 errmsg("cannot attach temporary relation of another session as partition")));
15624
15625 /* Check if there are any columns in attachrel that aren't in the parent */
15626 tupleDesc = RelationGetDescr(attachrel);
15627 natts = tupleDesc->natts;
15628 for (attno = 1; attno <= natts; attno++)
15629 {
15630 Form_pg_attribute attribute = TupleDescAttr(tupleDesc, attno - 1);
15631 char *attributeName = NameStr(attribute->attname);
15632
15633 /* Ignore dropped */
15634 if (attribute->attisdropped)
15635 continue;
15636
15637 /* Try to find the column in parent (matching on column name) */
15638 if (!SearchSysCacheExists2(ATTNAME,
15639 ObjectIdGetDatum(RelationGetRelid(rel)),
15640 CStringGetDatum(attributeName)))
15641 ereport(ERROR,
15642 (errcode(ERRCODE_DATATYPE_MISMATCH),
15643 errmsg("table \"%s\" contains column \"%s\" not found in parent \"%s\"",
15644 RelationGetRelationName(attachrel), attributeName,
15645 RelationGetRelationName(rel)),
15646 errdetail("The new partition may contain only the columns present in parent.")));
15647 }
15648
15649 /*
15650 * If child_rel has row-level triggers with transition tables, we
15651 * currently don't allow it to become a partition. See also prohibitions
15652 * in ATExecAddInherit() and CreateTrigger().
15653 */
15654 trigger_name = FindTriggerIncompatibleWithInheritance(attachrel->trigdesc);
15655 if (trigger_name != NULL)
15656 ereport(ERROR,
15657 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
15658 errmsg("trigger \"%s\" prevents table \"%s\" from becoming a partition",
15659 trigger_name, RelationGetRelationName(attachrel)),
15660 errdetail("ROW triggers with transition tables are not supported on partitions")));
15661
15662 /*
15663 * Check that the new partition's bound is valid and does not overlap any
15664 * of existing partitions of the parent - note that it does not return on
15665 * error.
15666 */
15667 check_new_partition_bound(RelationGetRelationName(attachrel), rel,
15668 cmd->bound);
15669
15670 /* OK to create inheritance. Rest of the checks performed there */
15671 CreateInheritance(attachrel, rel);
15672
15673 /* Update the pg_class entry. */
15674 StorePartitionBound(attachrel, rel, cmd->bound);
15675
15676 /* Ensure there exists a correct set of indexes in the partition. */
15677 AttachPartitionEnsureIndexes(rel, attachrel);
15678
15679 /* and triggers */
15680 CloneRowTriggersToPartition(rel, attachrel);
15681
15682 /*
15683 * Clone foreign key constraints. Callee is responsible for setting up
15684 * for phase 3 constraint verification.
15685 */
15686 CloneForeignKeyConstraints(wqueue, rel, attachrel);
15687
15688 /*
15689 * Generate partition constraint from the partition bound specification.
15690 * If the parent itself is a partition, make sure to include its
15691 * constraint as well.
15692 */
15693 partBoundConstraint = get_qual_from_partbound(attachrel, rel, cmd->bound);
15694 partConstraint = list_concat(partBoundConstraint,
15695 RelationGetPartitionQual(rel));
15696
15697 /* Skip validation if there are no constraints to validate. */
15698 if (partConstraint)
15699 {
15700 /*
15701 * Run the partition quals through const-simplification similar to
15702 * check constraints. We skip canonicalize_qual, though, because
15703 * partition quals should be in canonical form already.
15704 */
15705 partConstraint =
15706 (List *) eval_const_expressions(NULL,
15707 (Node *) partConstraint);
15708
15709 /* XXX this sure looks wrong */
15710 partConstraint = list_make1(make_ands_explicit(partConstraint));
15711
15712 /*
15713 * Adjust the generated constraint to match this partition's attribute
15714 * numbers.
15715 */
15716 partConstraint = map_partition_varattnos(partConstraint, 1, attachrel,
15717 rel, &found_whole_row);
15718 /* There can never be a whole-row reference here */
15719 if (found_whole_row)
15720 elog(ERROR,
15721 "unexpected whole-row reference found in partition key");
15722
15723 /* Validate partition constraints against the table being attached. */
15724 QueuePartitionConstraintValidation(wqueue, attachrel, partConstraint,
15725 false);
15726 }
15727
15728 /*
15729 * If we're attaching a partition other than the default partition and a
15730 * default one exists, then that partition's partition constraint changes,
15731 * so add an entry to the work queue to validate it, too. (We must not do
15732 * this when the partition being attached is the default one; we already
15733 * did it above!)
15734 */
15735 if (OidIsValid(defaultPartOid))
15736 {
15737 Relation defaultrel;
15738 List *defPartConstraint;
15739
15740 Assert(!cmd->bound->is_default);
15741
15742 /* we already hold a lock on the default partition */
15743 defaultrel = table_open(defaultPartOid, NoLock);
15744 defPartConstraint =
15745 get_proposed_default_constraint(partBoundConstraint);
15746
15747 /*
15748 * Map the Vars in the constraint expression from rel's attnos to
15749 * defaultrel's.
15750 */
15751 defPartConstraint =
15752 map_partition_varattnos(defPartConstraint,
15753 1, defaultrel, rel, NULL);
15754 QueuePartitionConstraintValidation(wqueue, defaultrel,
15755 defPartConstraint, true);
15756
15757 /* keep our lock until commit. */
15758 table_close(defaultrel, NoLock);
15759 }
15760
15761 ObjectAddressSet(address, RelationRelationId, RelationGetRelid(attachrel));
15762
15763 /* keep our lock until commit */
15764 table_close(attachrel, NoLock);
15765
15766 return address;
15767}
15768
15769/*
15770 * AttachPartitionEnsureIndexes
15771 * subroutine for ATExecAttachPartition to create/match indexes
15772 *
15773 * Enforce the indexing rule for partitioned tables during ALTER TABLE / ATTACH
15774 * PARTITION: every partition must have an index attached to each index on the
15775 * partitioned table.
15776 */
15777static void
15778AttachPartitionEnsureIndexes(Relation rel, Relation attachrel)
15779{
15780 List *idxes;
15781 List *attachRelIdxs;
15782 Relation *attachrelIdxRels;
15783 IndexInfo **attachInfos;
15784 int i;
15785 ListCell *cell;
15786 MemoryContext cxt;
15787 MemoryContext oldcxt;
15788
15789 cxt = AllocSetContextCreate(CurrentMemoryContext,
15790 "AttachPartitionEnsureIndexes",
15791 ALLOCSET_DEFAULT_SIZES);
15792 oldcxt = MemoryContextSwitchTo(cxt);
15793
15794 idxes = RelationGetIndexList(rel);
15795 attachRelIdxs = RelationGetIndexList(attachrel);
15796 attachrelIdxRels = palloc(sizeof(Relation) * list_length(attachRelIdxs));
15797 attachInfos = palloc(sizeof(IndexInfo *) * list_length(attachRelIdxs));
15798
15799 /* Build arrays of all existing indexes and their IndexInfos */
15800 i = 0;
15801 foreach(cell, attachRelIdxs)
15802 {
15803 Oid cldIdxId = lfirst_oid(cell);
15804
15805 attachrelIdxRels[i] = index_open(cldIdxId, AccessShareLock);
15806 attachInfos[i] = BuildIndexInfo(attachrelIdxRels[i]);
15807 i++;
15808 }
15809
15810 /*
15811 * If we're attaching a foreign table, we must fail if any of the indexes
15812 * is a constraint index; otherwise, there's nothing to do here. Do this
15813 * before starting work, to avoid wasting the effort of building a few
15814 * non-unique indexes before coming across a unique one.
15815 */
15816 if (attachrel->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
15817 {
15818 foreach(cell, idxes)
15819 {
15820 Oid idx = lfirst_oid(cell);
15821 Relation idxRel = index_open(idx, AccessShareLock);
15822
15823 if (idxRel->rd_index->indisunique ||
15824 idxRel->rd_index->indisprimary)
15825 ereport(ERROR,
15826 (errcode(ERRCODE_WRONG_OBJECT_TYPE),
15827 errmsg("cannot attach foreign table \"%s\" as partition of partitioned table \"%s\"",
15828 RelationGetRelationName(attachrel),
15829 RelationGetRelationName(rel)),
15830 errdetail("Table \"%s\" contains unique indexes.",
15831 RelationGetRelationName(rel))));
15832 index_close(idxRel, AccessShareLock);
15833 }
15834
15835 goto out;
15836 }
15837
15838 /*
15839 * For each index on the partitioned table, find a matching one in the
15840 * partition-to-be; if one is not found, create one.
15841 */
15842 foreach(cell, idxes)
15843 {
15844 Oid idx = lfirst_oid(cell);
15845 Relation idxRel = index_open(idx, AccessShareLock);
15846 IndexInfo *info;
15847 AttrNumber *attmap;
15848 bool found = false;
15849 Oid constraintOid;
15850
15851 /*
15852 * Ignore indexes in the partitioned table other than partitioned
15853 * indexes.
15854 */
15855 if (idxRel->rd_rel->relkind != RELKIND_PARTITIONED_INDEX)
15856 {
15857 index_close(idxRel, AccessShareLock);
15858 continue;
15859 }
15860
15861 /* construct an indexinfo to compare existing indexes against */
15862 info = BuildIndexInfo(idxRel);
15863 attmap = convert_tuples_by_name_map(RelationGetDescr(attachrel),
15864 RelationGetDescr(rel),
15865 gettext_noop("could not convert row type"));
15866 constraintOid = get_relation_idx_constraint_oid(RelationGetRelid(rel), idx);
15867
15868 /*
15869 * Scan the list of existing indexes in the partition-to-be, and mark
15870 * the first matching, unattached one we find, if any, as partition of
15871 * the parent index. If we find one, we're done.
15872 */
15873 for (i = 0; i < list_length(attachRelIdxs); i++)
15874 {
15875 Oid cldIdxId = RelationGetRelid(attachrelIdxRels[i]);
15876 Oid cldConstrOid = InvalidOid;
15877
15878 /* does this index have a parent? if so, can't use it */
15879 if (attachrelIdxRels[i]->rd_rel->relispartition)
15880 continue;
15881
15882 if (CompareIndexInfo(attachInfos[i], info,
15883 attachrelIdxRels[i]->rd_indcollation,
15884 idxRel->rd_indcollation,
15885 attachrelIdxRels[i]->rd_opfamily,
15886 idxRel->rd_opfamily,
15887 attmap,
15888 RelationGetDescr(rel)->natts))
15889 {
15890 /*
15891 * If this index is being created in the parent because of a
15892 * constraint, then the child needs to have a constraint also,
15893 * so look for one. If there is no such constraint, this
15894 * index is no good, so keep looking.
15895 */
15896 if (OidIsValid(constraintOid))
15897 {
15898 cldConstrOid =
15899 get_relation_idx_constraint_oid(RelationGetRelid(attachrel),
15900 cldIdxId);
15901 /* no dice */
15902 if (!OidIsValid(cldConstrOid))
15903 continue;
15904 }
15905
15906 /* bingo. */
15907 IndexSetParentIndex(attachrelIdxRels[i], idx);
15908 if (OidIsValid(constraintOid))
15909 ConstraintSetParentConstraint(cldConstrOid, constraintOid,
15910 RelationGetRelid(attachrel));
15911 found = true;
15912
15913 CommandCounterIncrement();
15914 break;
15915 }
15916 }
15917
15918 /*
15919 * If no suitable index was found in the partition-to-be, create one
15920 * now.
15921 */
15922 if (!found)
15923 {
15924 IndexStmt *stmt;
15925 Oid constraintOid;
15926
15927 stmt = generateClonedIndexStmt(NULL,
15928 idxRel, attmap,
15929 RelationGetDescr(rel)->natts,
15930 &constraintOid);
15931 DefineIndex(RelationGetRelid(attachrel), stmt, InvalidOid,
15932 RelationGetRelid(idxRel),
15933 constraintOid,
15934 true, false, false, false, false);
15935 }
15936
15937 index_close(idxRel, AccessShareLock);
15938 }
15939
15940out:
15941 /* Clean up. */
15942 for (i = 0; i < list_length(attachRelIdxs); i++)
15943 index_close(attachrelIdxRels[i], AccessShareLock);
15944 MemoryContextSwitchTo(oldcxt);
15945 MemoryContextDelete(cxt);
15946}
15947
15948/*
15949 * CloneRowTriggersToPartition
15950 * subroutine for ATExecAttachPartition/DefineRelation to create row
15951 * triggers on partitions
15952 */
15953static void
15954CloneRowTriggersToPartition(Relation parent, Relation partition)
15955{
15956 Relation pg_trigger;
15957 ScanKeyData key;
15958 SysScanDesc scan;
15959 HeapTuple tuple;
15960 MemoryContext perTupCxt;
15961
15962 ScanKeyInit(&key, Anum_pg_trigger_tgrelid, BTEqualStrategyNumber,
15963 F_OIDEQ, ObjectIdGetDatum(RelationGetRelid(parent)));
15964 pg_trigger = table_open(TriggerRelationId, RowExclusiveLock);
15965 scan = systable_beginscan(pg_trigger, TriggerRelidNameIndexId,
15966 true, NULL, 1, &key);
15967
15968 perTupCxt = AllocSetContextCreate(CurrentMemoryContext,
15969 "clone trig", ALLOCSET_SMALL_SIZES);
15970
15971 while (HeapTupleIsValid(tuple = systable_getnext(scan)))
15972 {
15973 Form_pg_trigger trigForm = (Form_pg_trigger) GETSTRUCT(tuple);
15974 CreateTrigStmt *trigStmt;
15975 Node *qual = NULL;
15976 Datum value;
15977 bool isnull;
15978 List *cols = NIL;
15979 List *trigargs = NIL;
15980 MemoryContext oldcxt;
15981
15982 /*
15983 * Ignore statement-level triggers; those are not cloned.
15984 */
15985 if (!TRIGGER_FOR_ROW(trigForm->tgtype))
15986 continue;
15987
15988 /* We don't clone internal triggers, either */
15989 if (trigForm->tgisinternal)
15990 continue;
15991
15992 /*
15993 * Complain if we find an unexpected trigger type.
15994 */
15995 if (!TRIGGER_FOR_AFTER(trigForm->tgtype))
15996 elog(ERROR, "unexpected trigger \"%s\" found",
15997 NameStr(trigForm->tgname));
15998
15999 /* Use short-lived context for CREATE TRIGGER */
16000 oldcxt = MemoryContextSwitchTo(perTupCxt);
16001
16002 /*
16003 * If there is a WHEN clause, generate a 'cooked' version of it that's
16004 * appropriate for the partition.
16005 */
16006 value = heap_getattr(tuple, Anum_pg_trigger_tgqual,
16007 RelationGetDescr(pg_trigger), &isnull);
16008 if (!isnull)
16009 {
16010 bool found_whole_row;
16011
16012 qual = stringToNode(TextDatumGetCString(value));
16013 qual = (Node *) map_partition_varattnos((List *) qual, PRS2_OLD_VARNO,
16014 partition, parent,
16015 &found_whole_row);
16016 if (found_whole_row)
16017 elog(ERROR, "unexpected whole-row reference found in trigger WHEN clause");
16018 qual = (Node *) map_partition_varattnos((List *) qual, PRS2_NEW_VARNO,
16019 partition, parent,
16020 &found_whole_row);
16021 if (found_whole_row)
16022 elog(ERROR, "unexpected whole-row reference found in trigger WHEN clause");
16023 }
16024
16025 /*
16026 * If there is a column list, transform it to a list of column names.
16027 * Note we don't need to map this list in any way ...
16028 */
16029 if (trigForm->tgattr.dim1 > 0)
16030 {
16031 int i;
16032
16033 for (i = 0; i < trigForm->tgattr.dim1; i++)
16034 {
16035 Form_pg_attribute col;
16036
16037 col = TupleDescAttr(parent->rd_att,
16038 trigForm->tgattr.values[i] - 1);
16039 cols = lappend(cols,
16040 makeString(pstrdup(NameStr(col->attname))));
16041 }
16042 }
16043
16044 /* Reconstruct trigger arguments list. */
16045 if (trigForm->tgnargs > 0)
16046 {
16047 char *p;
16048
16049 value = heap_getattr(tuple, Anum_pg_trigger_tgargs,
16050 RelationGetDescr(pg_trigger), &isnull);
16051 if (isnull)
16052 elog(ERROR, "tgargs is null for trigger \"%s\" in partition \"%s\"",
16053 NameStr(trigForm->tgname), RelationGetRelationName(partition));
16054
16055 p = (char *) VARDATA_ANY(DatumGetByteaPP(value));
16056
16057 for (int i = 0; i < trigForm->tgnargs; i++)
16058 {
16059 trigargs = lappend(trigargs, makeString(pstrdup(p)));
16060 p += strlen(p) + 1;
16061 }
16062 }
16063
16064 trigStmt = makeNode(CreateTrigStmt);
16065 trigStmt->trigname = NameStr(trigForm->tgname);
16066 trigStmt->relation = NULL;
16067 trigStmt->funcname = NULL; /* passed separately */
16068 trigStmt->args = trigargs;
16069 trigStmt->row = true;
16070 trigStmt->timing = trigForm->tgtype & TRIGGER_TYPE_TIMING_MASK;
16071 trigStmt->events = trigForm->tgtype & TRIGGER_TYPE_EVENT_MASK;
16072 trigStmt->columns = cols;
16073 trigStmt->whenClause = NULL; /* passed separately */
16074 trigStmt->isconstraint = OidIsValid(trigForm->tgconstraint);
16075 trigStmt->transitionRels = NIL; /* not supported at present */
16076 trigStmt->deferrable = trigForm->tgdeferrable;
16077 trigStmt->initdeferred = trigForm->tginitdeferred;
16078 trigStmt->constrrel = NULL; /* passed separately */
16079
16080 CreateTrigger(trigStmt, NULL, RelationGetRelid(partition),
16081 trigForm->tgconstrrelid, InvalidOid, InvalidOid,
16082 trigForm->tgfoid, trigForm->oid, qual,
16083 false, true);
16084
16085 MemoryContextSwitchTo(oldcxt);
16086 MemoryContextReset(perTupCxt);
16087 }
16088
16089 MemoryContextDelete(perTupCxt);
16090
16091 systable_endscan(scan);
16092 table_close(pg_trigger, RowExclusiveLock);
16093}
16094
16095/*
16096 * ALTER TABLE DETACH PARTITION
16097 *
16098 * Return the address of the relation that is no longer a partition of rel.
16099 */
16100static ObjectAddress
16101ATExecDetachPartition(Relation rel, RangeVar *name)
16102{
16103 Relation partRel,
16104 classRel;
16105 HeapTuple tuple,
16106 newtuple;
16107 Datum new_val[Natts_pg_class];
16108 bool new_null[Natts_pg_class],
16109 new_repl[Natts_pg_class];
16110 ObjectAddress address;
16111 Oid defaultPartOid;
16112 List *indexes;
16113 List *fks;
16114 ListCell *cell;
16115
16116 /*
16117 * We must lock the default partition, because detaching this partition
16118 * will change its partition constraint.
16119 */
16120 defaultPartOid =
16121 get_default_oid_from_partdesc(RelationGetPartitionDesc(rel));
16122 if (OidIsValid(defaultPartOid))
16123 LockRelationOid(defaultPartOid, AccessExclusiveLock);
16124
16125 partRel = table_openrv(name, ShareUpdateExclusiveLock);
16126
16127 /* Ensure that foreign keys still hold after this detach */
16128 ATDetachCheckNoForeignKeyRefs(partRel);
16129
16130 /* All inheritance related checks are performed within the function */
16131 RemoveInheritance(partRel, rel);
16132
16133 /* Update pg_class tuple */
16134 classRel = table_open(RelationRelationId, RowExclusiveLock);
16135 tuple = SearchSysCacheCopy1(RELOID,
16136 ObjectIdGetDatum(RelationGetRelid(partRel)));
16137 if (!HeapTupleIsValid(tuple))
16138 elog(ERROR, "cache lookup failed for relation %u",
16139 RelationGetRelid(partRel));
16140 Assert(((Form_pg_class) GETSTRUCT(tuple))->relispartition);
16141
16142 /* Clear relpartbound and reset relispartition */
16143 memset(new_val, 0, sizeof(new_val));
16144 memset(new_null, false, sizeof(new_null));
16145 memset(new_repl, false, sizeof(new_repl));
16146 new_val[Anum_pg_class_relpartbound - 1] = (Datum) 0;
16147 new_null[Anum_pg_class_relpartbound - 1] = true;
16148 new_repl[Anum_pg_class_relpartbound - 1] = true;
16149 newtuple = heap_modify_tuple(tuple, RelationGetDescr(classRel),
16150 new_val, new_null, new_repl);
16151
16152 ((Form_pg_class) GETSTRUCT(newtuple))->relispartition = false;
16153 CatalogTupleUpdate(classRel, &newtuple->t_self, newtuple);
16154 heap_freetuple(newtuple);
16155
16156 if (OidIsValid(defaultPartOid))
16157 {
16158 /*
16159 * If the relation being detached is the default partition itself,
16160 * remove it from the parent's pg_partitioned_table entry.
16161 *
16162 * If not, we must invalidate default partition's relcache entry, as
16163 * in StorePartitionBound: its partition constraint depends on every
16164 * other partition's partition constraint.
16165 */
16166 if (RelationGetRelid(partRel) == defaultPartOid)
16167 update_default_partition_oid(RelationGetRelid(rel), InvalidOid);
16168 else
16169 CacheInvalidateRelcacheByRelid(defaultPartOid);
16170 }
16171
16172 /* detach indexes too */
16173 indexes = RelationGetIndexList(partRel);
16174 foreach(cell, indexes)
16175 {
16176 Oid idxid = lfirst_oid(cell);
16177 Relation idx;
16178 Oid constrOid;
16179
16180 if (!has_superclass(idxid))
16181 continue;
16182
16183 Assert((IndexGetRelation(get_partition_parent(idxid), false) ==
16184 RelationGetRelid(rel)));
16185
16186 idx = index_open(idxid, AccessExclusiveLock);
16187 IndexSetParentIndex(idx, InvalidOid);
16188
16189 /* If there's a constraint associated with the index, detach it too */
16190 constrOid = get_relation_idx_constraint_oid(RelationGetRelid(partRel),
16191 idxid);
16192 if (OidIsValid(constrOid))
16193 ConstraintSetParentConstraint(constrOid, InvalidOid, InvalidOid);
16194
16195 index_close(idx, NoLock);
16196 }
16197 table_close(classRel, RowExclusiveLock);
16198
16199 /*
16200 * Detach any foreign keys that are inherited. This includes creating
16201 * additional action triggers.
16202 */
16203 fks = copyObject(RelationGetFKeyList(partRel));
16204 foreach(cell, fks)
16205 {
16206 ForeignKeyCacheInfo *fk = lfirst(cell);
16207 HeapTuple contup;
16208 Form_pg_constraint conform;
16209 Constraint *fkconstraint;
16210
16211 contup = SearchSysCache1(CONSTROID, ObjectIdGetDatum(fk->conoid));
16212 if (!HeapTupleIsValid(contup))
16213 elog(ERROR, "cache lookup failed for constraint %u", fk->conoid);
16214 conform = (Form_pg_constraint) GETSTRUCT(contup);
16215
16216 /* consider only the inherited foreign keys */
16217 if (conform->contype != CONSTRAINT_FOREIGN ||
16218 !OidIsValid(conform->conparentid))
16219 {
16220 ReleaseSysCache(contup);
16221 continue;
16222 }
16223
16224 /* unset conparentid and adjust conislocal, coninhcount, etc. */
16225 ConstraintSetParentConstraint(fk->conoid, InvalidOid, InvalidOid);
16226
16227 /*
16228 * Make the action triggers on the referenced relation. When this was
16229 * a partition the action triggers pointed to the parent rel (they
16230 * still do), but now we need separate ones of our own.
16231 */
16232 fkconstraint = makeNode(Constraint);
16233 fkconstraint->conname = pstrdup(NameStr(conform->conname));
16234 fkconstraint->fk_upd_action = conform->confupdtype;
16235 fkconstraint->fk_del_action = conform->confdeltype;
16236 fkconstraint->deferrable = conform->condeferrable;
16237 fkconstraint->initdeferred = conform->condeferred;
16238
16239 createForeignKeyActionTriggers(partRel, conform->confrelid,
16240 fkconstraint, fk->conoid,
16241 conform->conindid);
16242
16243 ReleaseSysCache(contup);
16244 }
16245 list_free_deep(fks);
16246
16247 /*
16248 * Any sub-constrains that are in the referenced-side of a larger
16249 * constraint have to be removed. This partition is no longer part of the
16250 * key space of the constraint.
16251 */
16252 foreach(cell, GetParentedForeignKeyRefs(partRel))
16253 {
16254 Oid constrOid = lfirst_oid(cell);
16255 ObjectAddress constraint;
16256
16257 ConstraintSetParentConstraint(constrOid, InvalidOid, InvalidOid);
16258 deleteDependencyRecordsForClass(ConstraintRelationId,
16259 constrOid,
16260 ConstraintRelationId,
16261 DEPENDENCY_INTERNAL);
16262 CommandCounterIncrement();
16263
16264 ObjectAddressSet(constraint, ConstraintRelationId, constrOid);
16265 performDeletion(&constraint, DROP_RESTRICT, 0);
16266 }
16267 CommandCounterIncrement();
16268
16269 /*
16270 * Invalidate the parent's relcache so that the partition is no longer
16271 * included in its partition descriptor.
16272 */
16273 CacheInvalidateRelcache(rel);
16274
16275 ObjectAddressSet(address, RelationRelationId, RelationGetRelid(partRel));
16276
16277 /* keep our lock until commit */
16278 table_close(partRel, NoLock);
16279
16280 return address;
16281}
16282
16283/*
16284 * Before acquiring lock on an index, acquire the same lock on the owning
16285 * table.
16286 */
16287struct AttachIndexCallbackState
16288{
16289 Oid partitionOid;
16290 Oid parentTblOid;
16291 bool lockedParentTbl;
16292};
16293
16294static void
16295RangeVarCallbackForAttachIndex(const RangeVar *rv, Oid relOid, Oid oldRelOid,
16296 void *arg)
16297{
16298 struct AttachIndexCallbackState *state;
16299 Form_pg_class classform;
16300 HeapTuple tuple;
16301
16302 state = (struct AttachIndexCallbackState *) arg;
16303
16304 if (!state->lockedParentTbl)
16305 {
16306 LockRelationOid(state->parentTblOid, AccessShareLock);
16307 state->lockedParentTbl = true;
16308 }
16309
16310 /*
16311 * If we previously locked some other heap, and the name we're looking up
16312 * no longer refers to an index on that relation, release the now-useless
16313 * lock. XXX maybe we should do *after* we verify whether the index does
16314 * not actually belong to the same relation ...
16315 */
16316 if (relOid != oldRelOid && OidIsValid(state->partitionOid))
16317 {
16318 UnlockRelationOid(state->partitionOid, AccessShareLock);
16319 state->partitionOid = InvalidOid;
16320 }
16321
16322 /* Didn't find a relation, so no need for locking or permission checks. */
16323 if (!OidIsValid(relOid))
16324 return;
16325
16326 tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relOid));
16327 if (!HeapTupleIsValid(tuple))
16328 return; /* concurrently dropped, so nothing to do */
16329 classform = (Form_pg_class) GETSTRUCT(tuple);
16330 if (classform->relkind != RELKIND_PARTITIONED_INDEX &&
16331 classform->relkind != RELKIND_INDEX)
16332 ereport(ERROR,
16333 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
16334 errmsg("\"%s\" is not an index", rv->relname)));
16335 ReleaseSysCache(tuple);
16336
16337 /*
16338 * Since we need only examine the heap's tupledesc, an access share lock
16339 * on it (preventing any DDL) is sufficient.
16340 */
16341 state->partitionOid = IndexGetRelation(relOid, false);
16342 LockRelationOid(state->partitionOid, AccessShareLock);
16343}
16344
16345/*
16346 * ALTER INDEX i1 ATTACH PARTITION i2
16347 */
16348static ObjectAddress
16349ATExecAttachPartitionIdx(List **wqueue, Relation parentIdx, RangeVar *name)
16350{
16351 Relation partIdx;
16352 Relation partTbl;
16353 Relation parentTbl;
16354 ObjectAddress address;
16355 Oid partIdxId;
16356 Oid currParent;
16357 struct AttachIndexCallbackState state;
16358
16359 /*
16360 * We need to obtain lock on the index 'name' to modify it, but we also
16361 * need to read its owning table's tuple descriptor -- so we need to lock
16362 * both. To avoid deadlocks, obtain lock on the table before doing so on
16363 * the index. Furthermore, we need to examine the parent table of the
16364 * partition, so lock that one too.
16365 */
16366 state.partitionOid = InvalidOid;
16367 state.parentTblOid = parentIdx->rd_index->indrelid;
16368 state.lockedParentTbl = false;
16369 partIdxId =
16370 RangeVarGetRelidExtended(name, AccessExclusiveLock, 0,
16371 RangeVarCallbackForAttachIndex,
16372 (void *) &state);
16373 /* Not there? */
16374 if (!OidIsValid(partIdxId))
16375 ereport(ERROR,
16376 (errcode(ERRCODE_UNDEFINED_OBJECT),
16377 errmsg("index \"%s\" does not exist", name->relname)));
16378
16379 /* no deadlock risk: RangeVarGetRelidExtended already acquired the lock */
16380 partIdx = relation_open(partIdxId, AccessExclusiveLock);
16381
16382 /* we already hold locks on both tables, so this is safe: */
16383 parentTbl = relation_open(parentIdx->rd_index->indrelid, AccessShareLock);
16384 partTbl = relation_open(partIdx->rd_index->indrelid, NoLock);
16385
16386 ObjectAddressSet(address, RelationRelationId, RelationGetRelid(partIdx));
16387
16388 /* Silently do nothing if already in the right state */
16389 currParent = partIdx->rd_rel->relispartition ?
16390 get_partition_parent(partIdxId) : InvalidOid;
16391 if (currParent != RelationGetRelid(parentIdx))
16392 {
16393 IndexInfo *childInfo;
16394 IndexInfo *parentInfo;
16395 AttrNumber *attmap;
16396 bool found;
16397 int i;
16398 PartitionDesc partDesc;
16399 Oid constraintOid,
16400 cldConstrId = InvalidOid;
16401
16402 /*
16403 * If this partition already has an index attached, refuse the
16404 * operation.
16405 */
16406 refuseDupeIndexAttach(parentIdx, partIdx, partTbl);
16407
16408 if (OidIsValid(currParent))
16409 ereport(ERROR,
16410 (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
16411 errmsg("cannot attach index \"%s\" as a partition of index \"%s\"",
16412 RelationGetRelationName(partIdx),
16413 RelationGetRelationName(parentIdx)),
16414 errdetail("Index \"%s\" is already attached to another index.",
16415 RelationGetRelationName(partIdx))));
16416
16417 /* Make sure it indexes a partition of the other index's table */
16418 partDesc = RelationGetPartitionDesc(parentTbl);
16419 found = false;
16420 for (i = 0; i < partDesc->nparts; i++)
16421 {
16422 if (partDesc->oids[i] == state.partitionOid)
16423 {
16424 found = true;
16425 break;
16426 }
16427 }
16428 if (!found)
16429 ereport(ERROR,
16430 (errmsg("cannot attach index \"%s\" as a partition of index \"%s\"",
16431 RelationGetRelationName(partIdx),
16432 RelationGetRelationName(parentIdx)),
16433 errdetail("Index \"%s\" is not an index on any partition of table \"%s\".",
16434 RelationGetRelationName(partIdx),
16435 RelationGetRelationName(parentTbl))));
16436
16437 /* Ensure the indexes are compatible */
16438 childInfo = BuildIndexInfo(partIdx);
16439 parentInfo = BuildIndexInfo(parentIdx);
16440 attmap = convert_tuples_by_name_map(RelationGetDescr(partTbl),
16441 RelationGetDescr(parentTbl),
16442 gettext_noop("could not convert row type"));
16443 if (!CompareIndexInfo(childInfo, parentInfo,
16444 partIdx->rd_indcollation,
16445 parentIdx->rd_indcollation,
16446 partIdx->rd_opfamily,
16447 parentIdx->rd_opfamily,
16448 attmap,
16449 RelationGetDescr(parentTbl)->natts))
16450 ereport(ERROR,
16451 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
16452 errmsg("cannot attach index \"%s\" as a partition of index \"%s\"",
16453 RelationGetRelationName(partIdx),
16454 RelationGetRelationName(parentIdx)),
16455 errdetail("The index definitions do not match.")));
16456
16457 /*
16458 * If there is a constraint in the parent, make sure there is one in
16459 * the child too.
16460 */
16461 constraintOid = get_relation_idx_constraint_oid(RelationGetRelid(parentTbl),
16462 RelationGetRelid(parentIdx));
16463
16464 if (OidIsValid(constraintOid))
16465 {
16466 cldConstrId = get_relation_idx_constraint_oid(RelationGetRelid(partTbl),
16467 partIdxId);
16468 if (!OidIsValid(cldConstrId))
16469 ereport(ERROR,
16470 (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
16471 errmsg("cannot attach index \"%s\" as a partition of index \"%s\"",
16472 RelationGetRelationName(partIdx),
16473 RelationGetRelationName(parentIdx)),
16474 errdetail("The index \"%s\" belongs to a constraint in table \"%s\" but no constraint exists for index \"%s\".",
16475 RelationGetRelationName(parentIdx),
16476 RelationGetRelationName(parentTbl),
16477 RelationGetRelationName(partIdx))));
16478 }
16479
16480 /* All good -- do it */
16481 IndexSetParentIndex(partIdx, RelationGetRelid(parentIdx));
16482 if (OidIsValid(constraintOid))
16483 ConstraintSetParentConstraint(cldConstrId, constraintOid,
16484 RelationGetRelid(partTbl));
16485
16486 pfree(attmap);
16487
16488 validatePartitionedIndex(parentIdx, parentTbl);
16489 }
16490
16491 relation_close(parentTbl, AccessShareLock);
16492 /* keep these locks till commit */
16493 relation_close(partTbl, NoLock);
16494 relation_close(partIdx, NoLock);
16495
16496 return address;
16497}
16498
16499/*
16500 * Verify whether the given partition already contains an index attached
16501 * to the given partitioned index. If so, raise an error.
16502 */
16503static void
16504refuseDupeIndexAttach(Relation parentIdx, Relation partIdx, Relation partitionTbl)
16505{
16506 Oid existingIdx;
16507
16508 existingIdx = index_get_partition(partitionTbl,
16509 RelationGetRelid(parentIdx));
16510 if (OidIsValid(existingIdx))
16511 ereport(ERROR,
16512 (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
16513 errmsg("cannot attach index \"%s\" as a partition of index \"%s\"",
16514 RelationGetRelationName(partIdx),
16515 RelationGetRelationName(parentIdx)),
16516 errdetail("Another index is already attached for partition \"%s\".",
16517 RelationGetRelationName(partitionTbl))));
16518}
16519
16520/*
16521 * Verify whether the set of attached partition indexes to a parent index on
16522 * a partitioned table is complete. If it is, mark the parent index valid.
16523 *
16524 * This should be called each time a partition index is attached.
16525 */
16526static void
16527validatePartitionedIndex(Relation partedIdx, Relation partedTbl)
16528{
16529 Relation inheritsRel;
16530 SysScanDesc scan;
16531 ScanKeyData key;
16532 int tuples = 0;
16533 HeapTuple inhTup;
16534 bool updated = false;
16535
16536 Assert(partedIdx->rd_rel->relkind == RELKIND_PARTITIONED_INDEX);
16537
16538 /*
16539 * Scan pg_inherits for this parent index. Count each valid index we find
16540 * (verifying the pg_index entry for each), and if we reach the total
16541 * amount we expect, we can mark this parent index as valid.
16542 */
16543 inheritsRel = table_open(InheritsRelationId, AccessShareLock);
16544 ScanKeyInit(&key, Anum_pg_inherits_inhparent,
16545 BTEqualStrategyNumber, F_OIDEQ,
16546 ObjectIdGetDatum(RelationGetRelid(partedIdx)));
16547 scan = systable_beginscan(inheritsRel, InheritsParentIndexId, true,
16548 NULL, 1, &key);
16549 while ((inhTup = systable_getnext(scan)) != NULL)
16550 {
16551 Form_pg_inherits inhForm = (Form_pg_inherits) GETSTRUCT(inhTup);
16552 HeapTuple indTup;
16553 Form_pg_index indexForm;
16554
16555 indTup = SearchSysCache1(INDEXRELID,
16556 ObjectIdGetDatum(inhForm->inhrelid));
16557 if (!HeapTupleIsValid(indTup))
16558 elog(ERROR, "cache lookup failed for index %u", inhForm->inhrelid);
16559 indexForm = (Form_pg_index) GETSTRUCT(indTup);
16560 if (indexForm->indisvalid)
16561 tuples += 1;
16562 ReleaseSysCache(indTup);
16563 }
16564
16565 /* Done with pg_inherits */
16566 systable_endscan(scan);
16567 table_close(inheritsRel, AccessShareLock);
16568
16569 /*
16570 * If we found as many inherited indexes as the partitioned table has
16571 * partitions, we're good; update pg_index to set indisvalid.
16572 */
16573 if (tuples == RelationGetPartitionDesc(partedTbl)->nparts)
16574 {
16575 Relation idxRel;
16576 HeapTuple newtup;
16577
16578 idxRel = table_open(IndexRelationId, RowExclusiveLock);
16579
16580 newtup = heap_copytuple(partedIdx->rd_indextuple);
16581 ((Form_pg_index) GETSTRUCT(newtup))->indisvalid = true;
16582 updated = true;
16583
16584 CatalogTupleUpdate(idxRel, &partedIdx->rd_indextuple->t_self, newtup);
16585
16586 table_close(idxRel, RowExclusiveLock);
16587 }
16588
16589 /*
16590 * If this index is in turn a partition of a larger index, validating it
16591 * might cause the parent to become valid also. Try that.
16592 */
16593 if (updated && partedIdx->rd_rel->relispartition)
16594 {
16595 Oid parentIdxId,
16596 parentTblId;
16597 Relation parentIdx,
16598 parentTbl;
16599
16600 /* make sure we see the validation we just did */
16601 CommandCounterIncrement();
16602
16603 parentIdxId = get_partition_parent(RelationGetRelid(partedIdx));
16604 parentTblId = get_partition_parent(RelationGetRelid(partedTbl));
16605 parentIdx = relation_open(parentIdxId, AccessExclusiveLock);
16606 parentTbl = relation_open(parentTblId, AccessExclusiveLock);
16607 Assert(!parentIdx->rd_index->indisvalid);
16608
16609 validatePartitionedIndex(parentIdx, parentTbl);
16610
16611 relation_close(parentIdx, AccessExclusiveLock);
16612 relation_close(parentTbl, AccessExclusiveLock);
16613 }
16614}
16615
16616/*
16617 * Return an OID list of constraints that reference the given relation
16618 * that are marked as having a parent constraints.
16619 */
16620static List *
16621GetParentedForeignKeyRefs(Relation partition)
16622{
16623 Relation pg_constraint;
16624 HeapTuple tuple;
16625 SysScanDesc scan;
16626 ScanKeyData key[2];
16627 List *constraints = NIL;
16628
16629 /*
16630 * If no indexes, or no columns are referenceable by FKs, we can avoid the
16631 * scan.
16632 */
16633 if (RelationGetIndexList(partition) == NIL ||
16634 bms_is_empty(RelationGetIndexAttrBitmap(partition,
16635 INDEX_ATTR_BITMAP_KEY)))
16636 return NIL;
16637
16638 /* Search for constraints referencing this table */
16639 pg_constraint = table_open(ConstraintRelationId, AccessShareLock);
16640 ScanKeyInit(&key[0],
16641 Anum_pg_constraint_confrelid, BTEqualStrategyNumber,
16642 F_OIDEQ, ObjectIdGetDatum(RelationGetRelid(partition)));
16643 ScanKeyInit(&key[1],
16644 Anum_pg_constraint_contype, BTEqualStrategyNumber,
16645 F_CHAREQ, CharGetDatum(CONSTRAINT_FOREIGN));
16646
16647 /* XXX This is a seqscan, as we don't have a usable index */
16648 scan = systable_beginscan(pg_constraint, InvalidOid, true, NULL, 2, key);
16649 while ((tuple = systable_getnext(scan)) != NULL)
16650 {
16651 Form_pg_constraint constrForm = (Form_pg_constraint) GETSTRUCT(tuple);
16652
16653 /*
16654 * We only need to process constraints that are part of larger ones.
16655 */
16656 if (!OidIsValid(constrForm->conparentid))
16657 continue;
16658
16659 constraints = lappend_oid(constraints, constrForm->oid);
16660 }
16661
16662 systable_endscan(scan);
16663 table_close(pg_constraint, AccessShareLock);
16664
16665 return constraints;
16666}
16667
16668/*
16669 * During DETACH PARTITION, verify that any foreign keys pointing to the
16670 * partitioned table would not become invalid. An error is raised if any
16671 * referenced values exist.
16672 */
16673static void
16674ATDetachCheckNoForeignKeyRefs(Relation partition)
16675{
16676 List *constraints;
16677 ListCell *cell;
16678
16679 constraints = GetParentedForeignKeyRefs(partition);
16680
16681 foreach(cell, constraints)
16682 {
16683 Oid constrOid = lfirst_oid(cell);
16684 HeapTuple tuple;
16685 Form_pg_constraint constrForm;
16686 Relation rel;
16687 Trigger trig;
16688
16689 tuple = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constrOid));
16690 if (!HeapTupleIsValid(tuple))
16691 elog(ERROR, "cache lookup failed for constraint %u", constrOid);
16692 constrForm = (Form_pg_constraint) GETSTRUCT(tuple);
16693
16694 Assert(OidIsValid(constrForm->conparentid));
16695 Assert(constrForm->confrelid == RelationGetRelid(partition));
16696
16697 /* prevent data changes into the referencing table until commit */
16698 rel = table_open(constrForm->conrelid, ShareLock);
16699
16700 MemSet(&trig, 0, sizeof(trig));
16701 trig.tgoid = InvalidOid;
16702 trig.tgname = NameStr(constrForm->conname);
16703 trig.tgenabled = TRIGGER_FIRES_ON_ORIGIN;
16704 trig.tgisinternal = true;
16705 trig.tgconstrrelid = RelationGetRelid(partition);
16706 trig.tgconstrindid = constrForm->conindid;
16707 trig.tgconstraint = constrForm->oid;
16708 trig.tgdeferrable = false;
16709 trig.tginitdeferred = false;
16710 /* we needn't fill in remaining fields */
16711
16712 RI_PartitionRemove_Check(&trig, rel, partition);
16713
16714 ReleaseSysCache(tuple);
16715
16716 table_close(rel, NoLock);
16717 }
16718}
16719