Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * ri_triggers.c
4 : *
5 : * Generic trigger procedures for referential integrity constraint
6 : * checks.
7 : *
8 : * Note about memory management: the private hashtables kept here live
9 : * across query and transaction boundaries, in fact they live as long as
10 : * the backend does. This works because the hashtable structures
11 : * themselves are allocated by dynahash.c in its permanent DynaHashCxt,
12 : * and the SPI plans they point to are saved using SPI_keepplan().
13 : * There is not currently any provision for throwing away a no-longer-needed
14 : * plan --- consider improving this someday.
15 : *
16 : *
17 : * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
18 : *
19 : * src/backend/utils/adt/ri_triggers.c
20 : *
21 : *-------------------------------------------------------------------------
22 : */
23 :
24 : #include "postgres.h"
25 :
26 : #include "access/htup_details.h"
27 : #include "access/sysattr.h"
28 : #include "access/table.h"
29 : #include "access/tableam.h"
30 : #include "access/xact.h"
31 : #include "catalog/pg_collation.h"
32 : #include "catalog/pg_constraint.h"
33 : #include "commands/trigger.h"
34 : #include "executor/executor.h"
35 : #include "executor/spi.h"
36 : #include "lib/ilist.h"
37 : #include "miscadmin.h"
38 : #include "parser/parse_coerce.h"
39 : #include "parser/parse_relation.h"
40 : #include "utils/acl.h"
41 : #include "utils/builtins.h"
42 : #include "utils/datum.h"
43 : #include "utils/fmgroids.h"
44 : #include "utils/guc.h"
45 : #include "utils/inval.h"
46 : #include "utils/lsyscache.h"
47 : #include "utils/memutils.h"
48 : #include "utils/rel.h"
49 : #include "utils/rls.h"
50 : #include "utils/ruleutils.h"
51 : #include "utils/snapmgr.h"
52 : #include "utils/syscache.h"
53 :
54 : /*
55 : * Local definitions
56 : */
57 :
58 : #define RI_MAX_NUMKEYS INDEX_MAX_KEYS
59 :
60 : #define RI_INIT_CONSTRAINTHASHSIZE 64
61 : #define RI_INIT_QUERYHASHSIZE (RI_INIT_CONSTRAINTHASHSIZE * 4)
62 :
63 : #define RI_KEYS_ALL_NULL 0
64 : #define RI_KEYS_SOME_NULL 1
65 : #define RI_KEYS_NONE_NULL 2
66 :
67 : /* RI query type codes */
68 : /* these queries are executed against the PK (referenced) table: */
69 : #define RI_PLAN_CHECK_LOOKUPPK 1
70 : #define RI_PLAN_CHECK_LOOKUPPK_FROM_PK 2
71 : #define RI_PLAN_LAST_ON_PK RI_PLAN_CHECK_LOOKUPPK_FROM_PK
72 : /* these queries are executed against the FK (referencing) table: */
73 : #define RI_PLAN_CASCADE_ONDELETE 3
74 : #define RI_PLAN_CASCADE_ONUPDATE 4
75 : #define RI_PLAN_NO_ACTION 5
76 : /* For RESTRICT, the same plan can be used for both ON DELETE and ON UPDATE triggers. */
77 : #define RI_PLAN_RESTRICT 6
78 : #define RI_PLAN_SETNULL_ONDELETE 7
79 : #define RI_PLAN_SETNULL_ONUPDATE 8
80 : #define RI_PLAN_SETDEFAULT_ONDELETE 9
81 : #define RI_PLAN_SETDEFAULT_ONUPDATE 10
82 :
83 : #define MAX_QUOTED_NAME_LEN (NAMEDATALEN*2+3)
84 : #define MAX_QUOTED_REL_NAME_LEN (MAX_QUOTED_NAME_LEN*2)
85 :
86 : #define RIAttName(rel, attnum) NameStr(*attnumAttName(rel, attnum))
87 : #define RIAttType(rel, attnum) attnumTypeId(rel, attnum)
88 : #define RIAttCollation(rel, attnum) attnumCollationId(rel, attnum)
89 :
90 : #define RI_TRIGTYPE_INSERT 1
91 : #define RI_TRIGTYPE_UPDATE 2
92 : #define RI_TRIGTYPE_DELETE 3
93 :
94 :
95 : /*
96 : * RI_ConstraintInfo
97 : *
98 : * Information extracted from an FK pg_constraint entry. This is cached in
99 : * ri_constraint_cache.
100 : *
101 : * Note that pf/pp/ff_eq_oprs may hold the overlaps operator instead of equals
102 : * for the PERIOD part of a temporal foreign key.
103 : */
104 : typedef struct RI_ConstraintInfo
105 : {
106 : Oid constraint_id; /* OID of pg_constraint entry (hash key) */
107 : bool valid; /* successfully initialized? */
108 : Oid constraint_root_id; /* OID of topmost ancestor constraint;
109 : * same as constraint_id if not inherited */
110 : uint32 oidHashValue; /* hash value of constraint_id */
111 : uint32 rootHashValue; /* hash value of constraint_root_id */
112 : NameData conname; /* name of the FK constraint */
113 : Oid pk_relid; /* referenced relation */
114 : Oid fk_relid; /* referencing relation */
115 : char confupdtype; /* foreign key's ON UPDATE action */
116 : char confdeltype; /* foreign key's ON DELETE action */
117 : int ndelsetcols; /* number of columns referenced in ON DELETE
118 : * SET clause */
119 : int16 confdelsetcols[RI_MAX_NUMKEYS]; /* attnums of cols to set on
120 : * delete */
121 : char confmatchtype; /* foreign key's match type */
122 : bool hasperiod; /* if the foreign key uses PERIOD */
123 : int nkeys; /* number of key columns */
124 : int16 pk_attnums[RI_MAX_NUMKEYS]; /* attnums of referenced cols */
125 : int16 fk_attnums[RI_MAX_NUMKEYS]; /* attnums of referencing cols */
126 : Oid pf_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (PK = FK) */
127 : Oid pp_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (PK = PK) */
128 : Oid ff_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (FK = FK) */
129 : Oid period_contained_by_oper; /* anyrange <@ anyrange */
130 : Oid agged_period_contained_by_oper; /* fkattr <@ range_agg(pkattr) */
131 : Oid period_intersect_oper; /* anyrange * anyrange */
132 : dlist_node valid_link; /* Link in list of valid entries */
133 : } RI_ConstraintInfo;
134 :
135 : /*
136 : * RI_QueryKey
137 : *
138 : * The key identifying a prepared SPI plan in our query hashtable
139 : */
140 : typedef struct RI_QueryKey
141 : {
142 : Oid constr_id; /* OID of pg_constraint entry */
143 : int32 constr_queryno; /* query type ID, see RI_PLAN_XXX above */
144 : } RI_QueryKey;
145 :
146 : /*
147 : * RI_QueryHashEntry
148 : */
149 : typedef struct RI_QueryHashEntry
150 : {
151 : RI_QueryKey key;
152 : SPIPlanPtr plan;
153 : } RI_QueryHashEntry;
154 :
155 : /*
156 : * RI_CompareKey
157 : *
158 : * The key identifying an entry showing how to compare two values
159 : */
160 : typedef struct RI_CompareKey
161 : {
162 : Oid eq_opr; /* the equality operator to apply */
163 : Oid typeid; /* the data type to apply it to */
164 : } RI_CompareKey;
165 :
166 : /*
167 : * RI_CompareHashEntry
168 : */
169 : typedef struct RI_CompareHashEntry
170 : {
171 : RI_CompareKey key;
172 : bool valid; /* successfully initialized? */
173 : FmgrInfo eq_opr_finfo; /* call info for equality fn */
174 : FmgrInfo cast_func_finfo; /* in case we must coerce input */
175 : } RI_CompareHashEntry;
176 :
177 :
178 : /*
179 : * Local data
180 : */
181 : static HTAB *ri_constraint_cache = NULL;
182 : static HTAB *ri_query_cache = NULL;
183 : static HTAB *ri_compare_cache = NULL;
184 : static dclist_head ri_constraint_cache_valid_list;
185 :
186 :
187 : /*
188 : * Local function prototypes
189 : */
190 : static bool ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
191 : TupleTableSlot *oldslot,
192 : const RI_ConstraintInfo *riinfo);
193 : static Datum ri_restrict(TriggerData *trigdata, bool is_no_action);
194 : static Datum ri_set(TriggerData *trigdata, bool is_set_null, int tgkind);
195 : static void quoteOneName(char *buffer, const char *name);
196 : static void quoteRelationName(char *buffer, Relation rel);
197 : static void ri_GenerateQual(StringInfo buf,
198 : const char *sep,
199 : const char *leftop, Oid leftoptype,
200 : Oid opoid,
201 : const char *rightop, Oid rightoptype);
202 : static void ri_GenerateQualCollation(StringInfo buf, Oid collation);
203 : static int ri_NullCheck(TupleDesc tupDesc, TupleTableSlot *slot,
204 : const RI_ConstraintInfo *riinfo, bool rel_is_pk);
205 : static void ri_BuildQueryKey(RI_QueryKey *key,
206 : const RI_ConstraintInfo *riinfo,
207 : int32 constr_queryno);
208 : static bool ri_KeysEqual(Relation rel, TupleTableSlot *oldslot, TupleTableSlot *newslot,
209 : const RI_ConstraintInfo *riinfo, bool rel_is_pk);
210 : static bool ri_CompareWithCast(Oid eq_opr, Oid typeid, Oid collid,
211 : Datum lhs, Datum rhs);
212 :
213 : static void ri_InitHashTables(void);
214 : static void InvalidateConstraintCacheCallBack(Datum arg, int cacheid, uint32 hashvalue);
215 : static SPIPlanPtr ri_FetchPreparedPlan(RI_QueryKey *key);
216 : static void ri_HashPreparedPlan(RI_QueryKey *key, SPIPlanPtr plan);
217 : static RI_CompareHashEntry *ri_HashCompareOp(Oid eq_opr, Oid typeid);
218 :
219 : static void ri_CheckTrigger(FunctionCallInfo fcinfo, const char *funcname,
220 : int tgkind);
221 : static const RI_ConstraintInfo *ri_FetchConstraintInfo(Trigger *trigger,
222 : Relation trig_rel, bool rel_is_pk);
223 : static const RI_ConstraintInfo *ri_LoadConstraintInfo(Oid constraintOid);
224 : static Oid get_ri_constraint_root(Oid constrOid);
225 : static SPIPlanPtr ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
226 : RI_QueryKey *qkey, Relation fk_rel, Relation pk_rel);
227 : static bool ri_PerformCheck(const RI_ConstraintInfo *riinfo,
228 : RI_QueryKey *qkey, SPIPlanPtr qplan,
229 : Relation fk_rel, Relation pk_rel,
230 : TupleTableSlot *oldslot, TupleTableSlot *newslot,
231 : bool is_restrict,
232 : bool detectNewRows, int expect_OK);
233 : static void ri_ExtractValues(Relation rel, TupleTableSlot *slot,
234 : const RI_ConstraintInfo *riinfo, bool rel_is_pk,
235 : Datum *vals, char *nulls);
236 : pg_noreturn static void ri_ReportViolation(const RI_ConstraintInfo *riinfo,
237 : Relation pk_rel, Relation fk_rel,
238 : TupleTableSlot *violatorslot, TupleDesc tupdesc,
239 : int queryno, bool is_restrict, bool partgone);
240 :
241 :
242 : /*
243 : * RI_FKey_check -
244 : *
245 : * Check foreign key existence (combined for INSERT and UPDATE).
246 : */
247 : static Datum
248 4518 : RI_FKey_check(TriggerData *trigdata)
249 : {
250 : const RI_ConstraintInfo *riinfo;
251 : Relation fk_rel;
252 : Relation pk_rel;
253 : TupleTableSlot *newslot;
254 : RI_QueryKey qkey;
255 : SPIPlanPtr qplan;
256 :
257 4518 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
258 : trigdata->tg_relation, false);
259 :
260 4518 : if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
261 448 : newslot = trigdata->tg_newslot;
262 : else
263 4070 : newslot = trigdata->tg_trigslot;
264 :
265 : /*
266 : * We should not even consider checking the row if it is no longer valid,
267 : * since it was either deleted (so the deferred check should be skipped)
268 : * or updated (in which case only the latest version of the row should be
269 : * checked). Test its liveness according to SnapshotSelf. We need pin
270 : * and lock on the buffer to call HeapTupleSatisfiesVisibility. Caller
271 : * should be holding pin, but not lock.
272 : */
273 4518 : if (!table_tuple_satisfies_snapshot(trigdata->tg_relation, newslot, SnapshotSelf))
274 60 : return PointerGetDatum(NULL);
275 :
276 : /*
277 : * Get the relation descriptors of the FK and PK tables.
278 : *
279 : * pk_rel is opened in RowShareLock mode since that's what our eventual
280 : * SELECT FOR KEY SHARE will get on it.
281 : */
282 4458 : fk_rel = trigdata->tg_relation;
283 4458 : pk_rel = table_open(riinfo->pk_relid, RowShareLock);
284 :
285 4458 : switch (ri_NullCheck(RelationGetDescr(fk_rel), newslot, riinfo, false))
286 : {
287 156 : case RI_KEYS_ALL_NULL:
288 :
289 : /*
290 : * No further check needed - an all-NULL key passes every type of
291 : * foreign key constraint.
292 : */
293 156 : table_close(pk_rel, RowShareLock);
294 156 : return PointerGetDatum(NULL);
295 :
296 158 : case RI_KEYS_SOME_NULL:
297 :
298 : /*
299 : * This is the only case that differs between the three kinds of
300 : * MATCH.
301 : */
302 158 : switch (riinfo->confmatchtype)
303 : {
304 36 : case FKCONSTR_MATCH_FULL:
305 :
306 : /*
307 : * Not allowed - MATCH FULL says either all or none of the
308 : * attributes can be NULLs
309 : */
310 36 : ereport(ERROR,
311 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
312 : errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
313 : RelationGetRelationName(fk_rel),
314 : NameStr(riinfo->conname)),
315 : errdetail("MATCH FULL does not allow mixing of null and nonnull key values."),
316 : errtableconstraint(fk_rel,
317 : NameStr(riinfo->conname))));
318 : table_close(pk_rel, RowShareLock);
319 : return PointerGetDatum(NULL);
320 :
321 122 : case FKCONSTR_MATCH_SIMPLE:
322 :
323 : /*
324 : * MATCH SIMPLE - if ANY column is null, the key passes
325 : * the constraint.
326 : */
327 122 : table_close(pk_rel, RowShareLock);
328 122 : return PointerGetDatum(NULL);
329 :
330 : #ifdef NOT_USED
331 : case FKCONSTR_MATCH_PARTIAL:
332 :
333 : /*
334 : * MATCH PARTIAL - all non-null columns must match. (not
335 : * implemented, can be done by modifying the query below
336 : * to only include non-null columns, or by writing a
337 : * special version here)
338 : */
339 : break;
340 : #endif
341 : }
342 :
343 : case RI_KEYS_NONE_NULL:
344 :
345 : /*
346 : * Have a full qualified key - continue below for all three kinds
347 : * of MATCH.
348 : */
349 4144 : break;
350 : }
351 :
352 4144 : SPI_connect();
353 :
354 : /* Fetch or prepare a saved plan for the real check */
355 4144 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CHECK_LOOKUPPK);
356 :
357 4144 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
358 : {
359 : StringInfoData querybuf;
360 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
361 : char attname[MAX_QUOTED_NAME_LEN];
362 : char paramname[16];
363 : const char *querysep;
364 : Oid queryoids[RI_MAX_NUMKEYS];
365 : const char *pk_only;
366 :
367 : /* ----------
368 : * The query string built is
369 : * SELECT 1 FROM [ONLY] <pktable> x WHERE pkatt1 = $1 [AND ...]
370 : * FOR KEY SHARE OF x
371 : * The type id's for the $ parameters are those of the
372 : * corresponding FK attributes.
373 : *
374 : * But for temporal FKs we need to make sure
375 : * the FK's range is completely covered.
376 : * So we use this query instead:
377 : * SELECT 1
378 : * FROM (
379 : * SELECT pkperiodatt AS r
380 : * FROM [ONLY] pktable x
381 : * WHERE pkatt1 = $1 [AND ...]
382 : * AND pkperiodatt && $n
383 : * FOR KEY SHARE OF x
384 : * ) x1
385 : * HAVING $n <@ range_agg(x1.r)
386 : * Note if FOR KEY SHARE ever allows GROUP BY and HAVING
387 : * we can make this a bit simpler.
388 : * ----------
389 : */
390 2180 : initStringInfo(&querybuf);
391 4360 : pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
392 2180 : "" : "ONLY ";
393 2180 : quoteRelationName(pkrelname, pk_rel);
394 2180 : if (riinfo->hasperiod)
395 : {
396 78 : quoteOneName(attname,
397 78 : RIAttName(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]));
398 :
399 78 : appendStringInfo(&querybuf,
400 : "SELECT 1 FROM (SELECT %s AS r FROM %s%s x",
401 : attname, pk_only, pkrelname);
402 : }
403 : else
404 : {
405 2102 : appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
406 : pk_only, pkrelname);
407 : }
408 2180 : querysep = "WHERE";
409 4672 : for (int i = 0; i < riinfo->nkeys; i++)
410 : {
411 2492 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
412 2492 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
413 :
414 2492 : quoteOneName(attname,
415 2492 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
416 2492 : sprintf(paramname, "$%d", i + 1);
417 2492 : ri_GenerateQual(&querybuf, querysep,
418 : attname, pk_type,
419 2492 : riinfo->pf_eq_oprs[i],
420 : paramname, fk_type);
421 2492 : querysep = "AND";
422 2492 : queryoids[i] = fk_type;
423 : }
424 2180 : appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
425 2180 : if (riinfo->hasperiod)
426 : {
427 78 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]);
428 :
429 78 : appendStringInfoString(&querybuf, ") x1 HAVING ");
430 78 : sprintf(paramname, "$%d", riinfo->nkeys);
431 78 : ri_GenerateQual(&querybuf, "",
432 : paramname, fk_type,
433 78 : riinfo->agged_period_contained_by_oper,
434 : "pg_catalog.range_agg", ANYMULTIRANGEOID);
435 78 : appendStringInfoString(&querybuf, "(x1.r)");
436 : }
437 :
438 : /* Prepare and save the plan */
439 2180 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
440 : &qkey, fk_rel, pk_rel);
441 : }
442 :
443 : /*
444 : * Now check that foreign key exists in PK table
445 : *
446 : * XXX detectNewRows must be true when a partitioned table is on the
447 : * referenced side. The reason is that our snapshot must be fresh in
448 : * order for the hack in find_inheritance_children() to work.
449 : */
450 4144 : ri_PerformCheck(riinfo, &qkey, qplan,
451 : fk_rel, pk_rel,
452 : NULL, newslot,
453 : false,
454 4144 : pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE,
455 : SPI_OK_SELECT);
456 :
457 3566 : if (SPI_finish() != SPI_OK_FINISH)
458 0 : elog(ERROR, "SPI_finish failed");
459 :
460 3566 : table_close(pk_rel, RowShareLock);
461 :
462 3566 : return PointerGetDatum(NULL);
463 : }
464 :
465 :
466 : /*
467 : * RI_FKey_check_ins -
468 : *
469 : * Check foreign key existence at insert event on FK table.
470 : */
471 : Datum
472 4070 : RI_FKey_check_ins(PG_FUNCTION_ARGS)
473 : {
474 : /* Check that this is a valid trigger call on the right time and event. */
475 4070 : ri_CheckTrigger(fcinfo, "RI_FKey_check_ins", RI_TRIGTYPE_INSERT);
476 :
477 : /* Share code with UPDATE case. */
478 4070 : return RI_FKey_check((TriggerData *) fcinfo->context);
479 : }
480 :
481 :
482 : /*
483 : * RI_FKey_check_upd -
484 : *
485 : * Check foreign key existence at update event on FK table.
486 : */
487 : Datum
488 448 : RI_FKey_check_upd(PG_FUNCTION_ARGS)
489 : {
490 : /* Check that this is a valid trigger call on the right time and event. */
491 448 : ri_CheckTrigger(fcinfo, "RI_FKey_check_upd", RI_TRIGTYPE_UPDATE);
492 :
493 : /* Share code with INSERT case. */
494 448 : return RI_FKey_check((TriggerData *) fcinfo->context);
495 : }
496 :
497 :
498 : /*
499 : * ri_Check_Pk_Match
500 : *
501 : * Check to see if another PK row has been created that provides the same
502 : * key values as the "oldslot" that's been modified or deleted in our trigger
503 : * event. Returns true if a match is found in the PK table.
504 : *
505 : * We assume the caller checked that the oldslot contains no NULL key values,
506 : * since otherwise a match is impossible.
507 : */
508 : static bool
509 786 : ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
510 : TupleTableSlot *oldslot,
511 : const RI_ConstraintInfo *riinfo)
512 : {
513 : SPIPlanPtr qplan;
514 : RI_QueryKey qkey;
515 : bool result;
516 :
517 : /* Only called for non-null rows */
518 : Assert(ri_NullCheck(RelationGetDescr(pk_rel), oldslot, riinfo, true) == RI_KEYS_NONE_NULL);
519 :
520 786 : SPI_connect();
521 :
522 : /*
523 : * Fetch or prepare a saved plan for checking PK table with values coming
524 : * from a PK row
525 : */
526 786 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CHECK_LOOKUPPK_FROM_PK);
527 :
528 786 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
529 : {
530 : StringInfoData querybuf;
531 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
532 : char attname[MAX_QUOTED_NAME_LEN];
533 : char paramname[16];
534 : const char *querysep;
535 : const char *pk_only;
536 : Oid queryoids[RI_MAX_NUMKEYS];
537 :
538 : /* ----------
539 : * The query string built is
540 : * SELECT 1 FROM [ONLY] <pktable> x WHERE pkatt1 = $1 [AND ...]
541 : * FOR KEY SHARE OF x
542 : * The type id's for the $ parameters are those of the
543 : * PK attributes themselves.
544 : *
545 : * But for temporal FKs we need to make sure
546 : * the old PK's range is completely covered.
547 : * So we use this query instead:
548 : * SELECT 1
549 : * FROM (
550 : * SELECT pkperiodatt AS r
551 : * FROM [ONLY] pktable x
552 : * WHERE pkatt1 = $1 [AND ...]
553 : * AND pkperiodatt && $n
554 : * FOR KEY SHARE OF x
555 : * ) x1
556 : * HAVING $n <@ range_agg(x1.r)
557 : * Note if FOR KEY SHARE ever allows GROUP BY and HAVING
558 : * we can make this a bit simpler.
559 : * ----------
560 : */
561 380 : initStringInfo(&querybuf);
562 760 : pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
563 380 : "" : "ONLY ";
564 380 : quoteRelationName(pkrelname, pk_rel);
565 380 : if (riinfo->hasperiod)
566 : {
567 0 : quoteOneName(attname, RIAttName(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]));
568 :
569 0 : appendStringInfo(&querybuf,
570 : "SELECT 1 FROM (SELECT %s AS r FROM %s%s x",
571 : attname, pk_only, pkrelname);
572 : }
573 : else
574 : {
575 380 : appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
576 : pk_only, pkrelname);
577 : }
578 380 : querysep = "WHERE";
579 884 : for (int i = 0; i < riinfo->nkeys; i++)
580 : {
581 504 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
582 :
583 504 : quoteOneName(attname,
584 504 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
585 504 : sprintf(paramname, "$%d", i + 1);
586 504 : ri_GenerateQual(&querybuf, querysep,
587 : attname, pk_type,
588 504 : riinfo->pp_eq_oprs[i],
589 : paramname, pk_type);
590 504 : querysep = "AND";
591 504 : queryoids[i] = pk_type;
592 : }
593 380 : appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
594 380 : if (riinfo->hasperiod)
595 : {
596 0 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]);
597 :
598 0 : appendStringInfoString(&querybuf, ") x1 HAVING ");
599 0 : sprintf(paramname, "$%d", riinfo->nkeys);
600 0 : ri_GenerateQual(&querybuf, "",
601 : paramname, fk_type,
602 0 : riinfo->agged_period_contained_by_oper,
603 : "pg_catalog.range_agg", ANYMULTIRANGEOID);
604 0 : appendStringInfoString(&querybuf, "(x1.r)");
605 : }
606 :
607 : /* Prepare and save the plan */
608 380 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
609 : &qkey, fk_rel, pk_rel);
610 : }
611 :
612 : /*
613 : * We have a plan now. Run it.
614 : */
615 786 : result = ri_PerformCheck(riinfo, &qkey, qplan,
616 : fk_rel, pk_rel,
617 : oldslot, NULL,
618 : false,
619 : true, /* treat like update */
620 : SPI_OK_SELECT);
621 :
622 786 : if (SPI_finish() != SPI_OK_FINISH)
623 0 : elog(ERROR, "SPI_finish failed");
624 :
625 786 : return result;
626 : }
627 :
628 :
629 : /*
630 : * RI_FKey_noaction_del -
631 : *
632 : * Give an error and roll back the current transaction if the
633 : * delete has resulted in a violation of the given referential
634 : * integrity constraint.
635 : */
636 : Datum
637 450 : RI_FKey_noaction_del(PG_FUNCTION_ARGS)
638 : {
639 : /* Check that this is a valid trigger call on the right time and event. */
640 450 : ri_CheckTrigger(fcinfo, "RI_FKey_noaction_del", RI_TRIGTYPE_DELETE);
641 :
642 : /* Share code with RESTRICT/UPDATE cases. */
643 450 : return ri_restrict((TriggerData *) fcinfo->context, true);
644 : }
645 :
646 : /*
647 : * RI_FKey_restrict_del -
648 : *
649 : * Restrict delete from PK table to rows unreferenced by foreign key.
650 : *
651 : * The SQL standard intends that this referential action occur exactly when
652 : * the delete is performed, rather than after. This appears to be
653 : * the only difference between "NO ACTION" and "RESTRICT". In Postgres
654 : * we still implement this as an AFTER trigger, but it's non-deferrable.
655 : */
656 : Datum
657 12 : RI_FKey_restrict_del(PG_FUNCTION_ARGS)
658 : {
659 : /* Check that this is a valid trigger call on the right time and event. */
660 12 : ri_CheckTrigger(fcinfo, "RI_FKey_restrict_del", RI_TRIGTYPE_DELETE);
661 :
662 : /* Share code with NO ACTION/UPDATE cases. */
663 12 : return ri_restrict((TriggerData *) fcinfo->context, false);
664 : }
665 :
666 : /*
667 : * RI_FKey_noaction_upd -
668 : *
669 : * Give an error and roll back the current transaction if the
670 : * update has resulted in a violation of the given referential
671 : * integrity constraint.
672 : */
673 : Datum
674 492 : RI_FKey_noaction_upd(PG_FUNCTION_ARGS)
675 : {
676 : /* Check that this is a valid trigger call on the right time and event. */
677 492 : ri_CheckTrigger(fcinfo, "RI_FKey_noaction_upd", RI_TRIGTYPE_UPDATE);
678 :
679 : /* Share code with RESTRICT/DELETE cases. */
680 492 : return ri_restrict((TriggerData *) fcinfo->context, true);
681 : }
682 :
683 : /*
684 : * RI_FKey_restrict_upd -
685 : *
686 : * Restrict update of PK to rows unreferenced by foreign key.
687 : *
688 : * The SQL standard intends that this referential action occur exactly when
689 : * the update is performed, rather than after. This appears to be
690 : * the only difference between "NO ACTION" and "RESTRICT". In Postgres
691 : * we still implement this as an AFTER trigger, but it's non-deferrable.
692 : */
693 : Datum
694 30 : RI_FKey_restrict_upd(PG_FUNCTION_ARGS)
695 : {
696 : /* Check that this is a valid trigger call on the right time and event. */
697 30 : ri_CheckTrigger(fcinfo, "RI_FKey_restrict_upd", RI_TRIGTYPE_UPDATE);
698 :
699 : /* Share code with NO ACTION/DELETE cases. */
700 30 : return ri_restrict((TriggerData *) fcinfo->context, false);
701 : }
702 :
703 : /*
704 : * ri_restrict -
705 : *
706 : * Common code for ON DELETE RESTRICT, ON DELETE NO ACTION,
707 : * ON UPDATE RESTRICT, and ON UPDATE NO ACTION.
708 : */
709 : static Datum
710 1116 : ri_restrict(TriggerData *trigdata, bool is_no_action)
711 : {
712 : const RI_ConstraintInfo *riinfo;
713 : Relation fk_rel;
714 : Relation pk_rel;
715 : TupleTableSlot *oldslot;
716 : RI_QueryKey qkey;
717 : SPIPlanPtr qplan;
718 :
719 1116 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
720 : trigdata->tg_relation, true);
721 :
722 : /*
723 : * Get the relation descriptors of the FK and PK tables and the old tuple.
724 : *
725 : * fk_rel is opened in RowShareLock mode since that's what our eventual
726 : * SELECT FOR KEY SHARE will get on it.
727 : */
728 1116 : fk_rel = table_open(riinfo->fk_relid, RowShareLock);
729 1116 : pk_rel = trigdata->tg_relation;
730 1116 : oldslot = trigdata->tg_trigslot;
731 :
732 : /*
733 : * If another PK row now exists providing the old key values, we should
734 : * not do anything. However, this check should only be made in the NO
735 : * ACTION case; in RESTRICT cases we don't wish to allow another row to be
736 : * substituted.
737 : *
738 : * If the foreign key has PERIOD, we incorporate looking for replacement
739 : * rows in the main SQL query below, so we needn't do it here.
740 : */
741 1902 : if (is_no_action && !riinfo->hasperiod &&
742 786 : ri_Check_Pk_Match(pk_rel, fk_rel, oldslot, riinfo))
743 : {
744 58 : table_close(fk_rel, RowShareLock);
745 58 : return PointerGetDatum(NULL);
746 : }
747 :
748 1058 : SPI_connect();
749 :
750 : /*
751 : * Fetch or prepare a saved plan for the restrict lookup (it's the same
752 : * query for delete and update cases)
753 : */
754 1058 : ri_BuildQueryKey(&qkey, riinfo, is_no_action ? RI_PLAN_NO_ACTION : RI_PLAN_RESTRICT);
755 :
756 1058 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
757 : {
758 : StringInfoData querybuf;
759 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
760 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
761 : char attname[MAX_QUOTED_NAME_LEN];
762 : char periodattname[MAX_QUOTED_NAME_LEN];
763 : char paramname[16];
764 : const char *querysep;
765 : Oid queryoids[RI_MAX_NUMKEYS];
766 : const char *fk_only;
767 :
768 : /* ----------
769 : * The query string built is
770 : * SELECT 1 FROM [ONLY] <fktable> x WHERE $1 = fkatt1 [AND ...]
771 : * FOR KEY SHARE OF x
772 : * The type id's for the $ parameters are those of the
773 : * corresponding PK attributes.
774 : * ----------
775 : */
776 444 : initStringInfo(&querybuf);
777 888 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
778 444 : "" : "ONLY ";
779 444 : quoteRelationName(fkrelname, fk_rel);
780 444 : appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
781 : fk_only, fkrelname);
782 444 : querysep = "WHERE";
783 1116 : for (int i = 0; i < riinfo->nkeys; i++)
784 : {
785 672 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
786 672 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
787 :
788 672 : quoteOneName(attname,
789 672 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
790 672 : sprintf(paramname, "$%d", i + 1);
791 672 : ri_GenerateQual(&querybuf, querysep,
792 : paramname, pk_type,
793 672 : riinfo->pf_eq_oprs[i],
794 : attname, fk_type);
795 672 : querysep = "AND";
796 672 : queryoids[i] = pk_type;
797 : }
798 :
799 : /*----------
800 : * For temporal foreign keys, a reference could still be valid if the
801 : * referenced range didn't change too much. Also if a referencing
802 : * range extends past the current PK row, we don't want to check that
803 : * part: some other PK row should fulfill it. We only want to check
804 : * the part matching the PK record we've changed. Therefore to find
805 : * invalid records we do this:
806 : *
807 : * SELECT 1 FROM [ONLY] <fktable> x WHERE $1 = x.fkatt1 [AND ...]
808 : * -- begin temporal
809 : * AND $n && x.fkperiod
810 : * AND NOT coalesce((x.fkperiod * $n) <@
811 : * (SELECT range_agg(r)
812 : * FROM (SELECT y.pkperiod r
813 : * FROM [ONLY] <pktable> y
814 : * WHERE $1 = y.pkatt1 [AND ...] AND $n && y.pkperiod
815 : * FOR KEY SHARE OF y) y2), false)
816 : * -- end temporal
817 : * FOR KEY SHARE OF x
818 : *
819 : * We need the coalesce in case the first subquery returns no rows.
820 : * We need the second subquery because FOR KEY SHARE doesn't support
821 : * aggregate queries.
822 : */
823 444 : if (riinfo->hasperiod && is_no_action)
824 : {
825 104 : Oid pk_period_type = RIAttType(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]);
826 104 : Oid fk_period_type = RIAttType(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]);
827 : StringInfoData intersectbuf;
828 : StringInfoData replacementsbuf;
829 208 : char *pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
830 104 : "" : "ONLY ";
831 :
832 104 : quoteOneName(attname, RIAttName(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]));
833 104 : sprintf(paramname, "$%d", riinfo->nkeys);
834 :
835 104 : appendStringInfoString(&querybuf, " AND NOT coalesce(");
836 :
837 : /* Intersect the fk with the old pk range */
838 104 : initStringInfo(&intersectbuf);
839 104 : appendStringInfoChar(&intersectbuf, '(');
840 104 : ri_GenerateQual(&intersectbuf, "",
841 : attname, fk_period_type,
842 104 : riinfo->period_intersect_oper,
843 : paramname, pk_period_type);
844 104 : appendStringInfoChar(&intersectbuf, ')');
845 :
846 : /* Find the remaining history */
847 104 : initStringInfo(&replacementsbuf);
848 104 : appendStringInfoString(&replacementsbuf, "(SELECT pg_catalog.range_agg(r) FROM ");
849 :
850 104 : quoteOneName(periodattname, RIAttName(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]));
851 104 : quoteRelationName(pkrelname, pk_rel);
852 104 : appendStringInfo(&replacementsbuf, "(SELECT y.%s r FROM %s%s y",
853 : periodattname, pk_only, pkrelname);
854 :
855 : /* Restrict pk rows to what matches */
856 104 : querysep = "WHERE";
857 312 : for (int i = 0; i < riinfo->nkeys; i++)
858 : {
859 208 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
860 :
861 208 : quoteOneName(attname,
862 208 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
863 208 : sprintf(paramname, "$%d", i + 1);
864 208 : ri_GenerateQual(&replacementsbuf, querysep,
865 : paramname, pk_type,
866 208 : riinfo->pp_eq_oprs[i],
867 : attname, pk_type);
868 208 : querysep = "AND";
869 208 : queryoids[i] = pk_type;
870 : }
871 104 : appendStringInfoString(&replacementsbuf, " FOR KEY SHARE OF y) y2)");
872 :
873 104 : ri_GenerateQual(&querybuf, "",
874 104 : intersectbuf.data, fk_period_type,
875 104 : riinfo->agged_period_contained_by_oper,
876 104 : replacementsbuf.data, ANYMULTIRANGEOID);
877 : /* end of coalesce: */
878 104 : appendStringInfoString(&querybuf, ", false)");
879 : }
880 :
881 444 : appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
882 :
883 : /* Prepare and save the plan */
884 444 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
885 : &qkey, fk_rel, pk_rel);
886 : }
887 :
888 : /*
889 : * We have a plan now. Run it to check for existing references.
890 : */
891 1058 : ri_PerformCheck(riinfo, &qkey, qplan,
892 : fk_rel, pk_rel,
893 : oldslot, NULL,
894 1058 : !is_no_action,
895 : true, /* must detect new rows */
896 1058 : SPI_OK_SELECT);
897 :
898 592 : if (SPI_finish() != SPI_OK_FINISH)
899 0 : elog(ERROR, "SPI_finish failed");
900 :
901 592 : table_close(fk_rel, RowShareLock);
902 :
903 592 : return PointerGetDatum(NULL);
904 : }
905 :
906 :
907 : /*
908 : * RI_FKey_cascade_del -
909 : *
910 : * Cascaded delete foreign key references at delete event on PK table.
911 : */
912 : Datum
913 148 : RI_FKey_cascade_del(PG_FUNCTION_ARGS)
914 : {
915 148 : TriggerData *trigdata = (TriggerData *) fcinfo->context;
916 : const RI_ConstraintInfo *riinfo;
917 : Relation fk_rel;
918 : Relation pk_rel;
919 : TupleTableSlot *oldslot;
920 : RI_QueryKey qkey;
921 : SPIPlanPtr qplan;
922 :
923 : /* Check that this is a valid trigger call on the right time and event. */
924 148 : ri_CheckTrigger(fcinfo, "RI_FKey_cascade_del", RI_TRIGTYPE_DELETE);
925 :
926 148 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
927 : trigdata->tg_relation, true);
928 :
929 : /*
930 : * Get the relation descriptors of the FK and PK tables and the old tuple.
931 : *
932 : * fk_rel is opened in RowExclusiveLock mode since that's what our
933 : * eventual DELETE will get on it.
934 : */
935 148 : fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
936 148 : pk_rel = trigdata->tg_relation;
937 148 : oldslot = trigdata->tg_trigslot;
938 :
939 148 : SPI_connect();
940 :
941 : /* Fetch or prepare a saved plan for the cascaded delete */
942 148 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CASCADE_ONDELETE);
943 :
944 148 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
945 : {
946 : StringInfoData querybuf;
947 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
948 : char attname[MAX_QUOTED_NAME_LEN];
949 : char paramname[16];
950 : const char *querysep;
951 : Oid queryoids[RI_MAX_NUMKEYS];
952 : const char *fk_only;
953 :
954 : /* ----------
955 : * The query string built is
956 : * DELETE FROM [ONLY] <fktable> WHERE $1 = fkatt1 [AND ...]
957 : * The type id's for the $ parameters are those of the
958 : * corresponding PK attributes.
959 : * ----------
960 : */
961 92 : initStringInfo(&querybuf);
962 184 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
963 92 : "" : "ONLY ";
964 92 : quoteRelationName(fkrelname, fk_rel);
965 92 : appendStringInfo(&querybuf, "DELETE FROM %s%s",
966 : fk_only, fkrelname);
967 92 : querysep = "WHERE";
968 210 : for (int i = 0; i < riinfo->nkeys; i++)
969 : {
970 118 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
971 118 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
972 :
973 118 : quoteOneName(attname,
974 118 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
975 118 : sprintf(paramname, "$%d", i + 1);
976 118 : ri_GenerateQual(&querybuf, querysep,
977 : paramname, pk_type,
978 118 : riinfo->pf_eq_oprs[i],
979 : attname, fk_type);
980 118 : querysep = "AND";
981 118 : queryoids[i] = pk_type;
982 : }
983 :
984 : /* Prepare and save the plan */
985 92 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
986 : &qkey, fk_rel, pk_rel);
987 : }
988 :
989 : /*
990 : * We have a plan now. Build up the arguments from the key values in the
991 : * deleted PK tuple and delete the referencing rows
992 : */
993 148 : ri_PerformCheck(riinfo, &qkey, qplan,
994 : fk_rel, pk_rel,
995 : oldslot, NULL,
996 : false,
997 : true, /* must detect new rows */
998 : SPI_OK_DELETE);
999 :
1000 146 : if (SPI_finish() != SPI_OK_FINISH)
1001 0 : elog(ERROR, "SPI_finish failed");
1002 :
1003 146 : table_close(fk_rel, RowExclusiveLock);
1004 :
1005 146 : return PointerGetDatum(NULL);
1006 : }
1007 :
1008 :
1009 : /*
1010 : * RI_FKey_cascade_upd -
1011 : *
1012 : * Cascaded update foreign key references at update event on PK table.
1013 : */
1014 : Datum
1015 204 : RI_FKey_cascade_upd(PG_FUNCTION_ARGS)
1016 : {
1017 204 : TriggerData *trigdata = (TriggerData *) fcinfo->context;
1018 : const RI_ConstraintInfo *riinfo;
1019 : Relation fk_rel;
1020 : Relation pk_rel;
1021 : TupleTableSlot *newslot;
1022 : TupleTableSlot *oldslot;
1023 : RI_QueryKey qkey;
1024 : SPIPlanPtr qplan;
1025 :
1026 : /* Check that this is a valid trigger call on the right time and event. */
1027 204 : ri_CheckTrigger(fcinfo, "RI_FKey_cascade_upd", RI_TRIGTYPE_UPDATE);
1028 :
1029 204 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
1030 : trigdata->tg_relation, true);
1031 :
1032 : /*
1033 : * Get the relation descriptors of the FK and PK tables and the new and
1034 : * old tuple.
1035 : *
1036 : * fk_rel is opened in RowExclusiveLock mode since that's what our
1037 : * eventual UPDATE will get on it.
1038 : */
1039 204 : fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
1040 204 : pk_rel = trigdata->tg_relation;
1041 204 : newslot = trigdata->tg_newslot;
1042 204 : oldslot = trigdata->tg_trigslot;
1043 :
1044 204 : SPI_connect();
1045 :
1046 : /* Fetch or prepare a saved plan for the cascaded update */
1047 204 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CASCADE_ONUPDATE);
1048 :
1049 204 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
1050 : {
1051 : StringInfoData querybuf;
1052 : StringInfoData qualbuf;
1053 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1054 : char attname[MAX_QUOTED_NAME_LEN];
1055 : char paramname[16];
1056 : const char *querysep;
1057 : const char *qualsep;
1058 : Oid queryoids[RI_MAX_NUMKEYS * 2];
1059 : const char *fk_only;
1060 :
1061 : /* ----------
1062 : * The query string built is
1063 : * UPDATE [ONLY] <fktable> SET fkatt1 = $1 [, ...]
1064 : * WHERE $n = fkatt1 [AND ...]
1065 : * The type id's for the $ parameters are those of the
1066 : * corresponding PK attributes. Note that we are assuming
1067 : * there is an assignment cast from the PK to the FK type;
1068 : * else the parser will fail.
1069 : * ----------
1070 : */
1071 114 : initStringInfo(&querybuf);
1072 114 : initStringInfo(&qualbuf);
1073 228 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1074 114 : "" : "ONLY ";
1075 114 : quoteRelationName(fkrelname, fk_rel);
1076 114 : appendStringInfo(&querybuf, "UPDATE %s%s SET",
1077 : fk_only, fkrelname);
1078 114 : querysep = "";
1079 114 : qualsep = "WHERE";
1080 252 : for (int i = 0, j = riinfo->nkeys; i < riinfo->nkeys; i++, j++)
1081 : {
1082 138 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1083 138 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1084 :
1085 138 : quoteOneName(attname,
1086 138 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1087 138 : appendStringInfo(&querybuf,
1088 : "%s %s = $%d",
1089 : querysep, attname, i + 1);
1090 138 : sprintf(paramname, "$%d", j + 1);
1091 138 : ri_GenerateQual(&qualbuf, qualsep,
1092 : paramname, pk_type,
1093 138 : riinfo->pf_eq_oprs[i],
1094 : attname, fk_type);
1095 138 : querysep = ",";
1096 138 : qualsep = "AND";
1097 138 : queryoids[i] = pk_type;
1098 138 : queryoids[j] = pk_type;
1099 : }
1100 114 : appendBinaryStringInfo(&querybuf, qualbuf.data, qualbuf.len);
1101 :
1102 : /* Prepare and save the plan */
1103 114 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys * 2, queryoids,
1104 : &qkey, fk_rel, pk_rel);
1105 : }
1106 :
1107 : /*
1108 : * We have a plan now. Run it to update the existing references.
1109 : */
1110 204 : ri_PerformCheck(riinfo, &qkey, qplan,
1111 : fk_rel, pk_rel,
1112 : oldslot, newslot,
1113 : false,
1114 : true, /* must detect new rows */
1115 : SPI_OK_UPDATE);
1116 :
1117 204 : if (SPI_finish() != SPI_OK_FINISH)
1118 0 : elog(ERROR, "SPI_finish failed");
1119 :
1120 204 : table_close(fk_rel, RowExclusiveLock);
1121 :
1122 204 : return PointerGetDatum(NULL);
1123 : }
1124 :
1125 :
1126 : /*
1127 : * RI_FKey_setnull_del -
1128 : *
1129 : * Set foreign key references to NULL values at delete event on PK table.
1130 : */
1131 : Datum
1132 98 : RI_FKey_setnull_del(PG_FUNCTION_ARGS)
1133 : {
1134 : /* Check that this is a valid trigger call on the right time and event. */
1135 98 : ri_CheckTrigger(fcinfo, "RI_FKey_setnull_del", RI_TRIGTYPE_DELETE);
1136 :
1137 : /* Share code with UPDATE case */
1138 98 : return ri_set((TriggerData *) fcinfo->context, true, RI_TRIGTYPE_DELETE);
1139 : }
1140 :
1141 : /*
1142 : * RI_FKey_setnull_upd -
1143 : *
1144 : * Set foreign key references to NULL at update event on PK table.
1145 : */
1146 : Datum
1147 30 : RI_FKey_setnull_upd(PG_FUNCTION_ARGS)
1148 : {
1149 : /* Check that this is a valid trigger call on the right time and event. */
1150 30 : ri_CheckTrigger(fcinfo, "RI_FKey_setnull_upd", RI_TRIGTYPE_UPDATE);
1151 :
1152 : /* Share code with DELETE case */
1153 30 : return ri_set((TriggerData *) fcinfo->context, true, RI_TRIGTYPE_UPDATE);
1154 : }
1155 :
1156 : /*
1157 : * RI_FKey_setdefault_del -
1158 : *
1159 : * Set foreign key references to defaults at delete event on PK table.
1160 : */
1161 : Datum
1162 84 : RI_FKey_setdefault_del(PG_FUNCTION_ARGS)
1163 : {
1164 : /* Check that this is a valid trigger call on the right time and event. */
1165 84 : ri_CheckTrigger(fcinfo, "RI_FKey_setdefault_del", RI_TRIGTYPE_DELETE);
1166 :
1167 : /* Share code with UPDATE case */
1168 84 : return ri_set((TriggerData *) fcinfo->context, false, RI_TRIGTYPE_DELETE);
1169 : }
1170 :
1171 : /*
1172 : * RI_FKey_setdefault_upd -
1173 : *
1174 : * Set foreign key references to defaults at update event on PK table.
1175 : */
1176 : Datum
1177 48 : RI_FKey_setdefault_upd(PG_FUNCTION_ARGS)
1178 : {
1179 : /* Check that this is a valid trigger call on the right time and event. */
1180 48 : ri_CheckTrigger(fcinfo, "RI_FKey_setdefault_upd", RI_TRIGTYPE_UPDATE);
1181 :
1182 : /* Share code with DELETE case */
1183 48 : return ri_set((TriggerData *) fcinfo->context, false, RI_TRIGTYPE_UPDATE);
1184 : }
1185 :
1186 : /*
1187 : * ri_set -
1188 : *
1189 : * Common code for ON DELETE SET NULL, ON DELETE SET DEFAULT, ON UPDATE SET
1190 : * NULL, and ON UPDATE SET DEFAULT.
1191 : */
1192 : static Datum
1193 260 : ri_set(TriggerData *trigdata, bool is_set_null, int tgkind)
1194 : {
1195 : const RI_ConstraintInfo *riinfo;
1196 : Relation fk_rel;
1197 : Relation pk_rel;
1198 : TupleTableSlot *oldslot;
1199 : RI_QueryKey qkey;
1200 : SPIPlanPtr qplan;
1201 : int32 queryno;
1202 :
1203 260 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
1204 : trigdata->tg_relation, true);
1205 :
1206 : /*
1207 : * Get the relation descriptors of the FK and PK tables and the old tuple.
1208 : *
1209 : * fk_rel is opened in RowExclusiveLock mode since that's what our
1210 : * eventual UPDATE will get on it.
1211 : */
1212 260 : fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
1213 260 : pk_rel = trigdata->tg_relation;
1214 260 : oldslot = trigdata->tg_trigslot;
1215 :
1216 260 : SPI_connect();
1217 :
1218 : /*
1219 : * Fetch or prepare a saved plan for the trigger.
1220 : */
1221 260 : switch (tgkind)
1222 : {
1223 78 : case RI_TRIGTYPE_UPDATE:
1224 78 : queryno = is_set_null
1225 : ? RI_PLAN_SETNULL_ONUPDATE
1226 78 : : RI_PLAN_SETDEFAULT_ONUPDATE;
1227 78 : break;
1228 182 : case RI_TRIGTYPE_DELETE:
1229 182 : queryno = is_set_null
1230 : ? RI_PLAN_SETNULL_ONDELETE
1231 182 : : RI_PLAN_SETDEFAULT_ONDELETE;
1232 182 : break;
1233 0 : default:
1234 0 : elog(ERROR, "invalid tgkind passed to ri_set");
1235 : }
1236 :
1237 260 : ri_BuildQueryKey(&qkey, riinfo, queryno);
1238 :
1239 260 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
1240 : {
1241 : StringInfoData querybuf;
1242 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1243 : char attname[MAX_QUOTED_NAME_LEN];
1244 : char paramname[16];
1245 : const char *querysep;
1246 : const char *qualsep;
1247 : Oid queryoids[RI_MAX_NUMKEYS];
1248 : const char *fk_only;
1249 : int num_cols_to_set;
1250 : const int16 *set_cols;
1251 :
1252 148 : switch (tgkind)
1253 : {
1254 48 : case RI_TRIGTYPE_UPDATE:
1255 48 : num_cols_to_set = riinfo->nkeys;
1256 48 : set_cols = riinfo->fk_attnums;
1257 48 : break;
1258 100 : case RI_TRIGTYPE_DELETE:
1259 :
1260 : /*
1261 : * If confdelsetcols are present, then we only update the
1262 : * columns specified in that array, otherwise we update all
1263 : * the referencing columns.
1264 : */
1265 100 : if (riinfo->ndelsetcols != 0)
1266 : {
1267 24 : num_cols_to_set = riinfo->ndelsetcols;
1268 24 : set_cols = riinfo->confdelsetcols;
1269 : }
1270 : else
1271 : {
1272 76 : num_cols_to_set = riinfo->nkeys;
1273 76 : set_cols = riinfo->fk_attnums;
1274 : }
1275 100 : break;
1276 0 : default:
1277 0 : elog(ERROR, "invalid tgkind passed to ri_set");
1278 : }
1279 :
1280 : /* ----------
1281 : * The query string built is
1282 : * UPDATE [ONLY] <fktable> SET fkatt1 = {NULL|DEFAULT} [, ...]
1283 : * WHERE $1 = fkatt1 [AND ...]
1284 : * The type id's for the $ parameters are those of the
1285 : * corresponding PK attributes.
1286 : * ----------
1287 : */
1288 148 : initStringInfo(&querybuf);
1289 296 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1290 148 : "" : "ONLY ";
1291 148 : quoteRelationName(fkrelname, fk_rel);
1292 148 : appendStringInfo(&querybuf, "UPDATE %s%s SET",
1293 : fk_only, fkrelname);
1294 :
1295 : /*
1296 : * Add assignment clauses
1297 : */
1298 148 : querysep = "";
1299 388 : for (int i = 0; i < num_cols_to_set; i++)
1300 : {
1301 240 : quoteOneName(attname, RIAttName(fk_rel, set_cols[i]));
1302 240 : appendStringInfo(&querybuf,
1303 : "%s %s = %s",
1304 : querysep, attname,
1305 : is_set_null ? "NULL" : "DEFAULT");
1306 240 : querysep = ",";
1307 : }
1308 :
1309 : /*
1310 : * Add WHERE clause
1311 : */
1312 148 : qualsep = "WHERE";
1313 412 : for (int i = 0; i < riinfo->nkeys; i++)
1314 : {
1315 264 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1316 264 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1317 :
1318 264 : quoteOneName(attname,
1319 264 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1320 :
1321 264 : sprintf(paramname, "$%d", i + 1);
1322 264 : ri_GenerateQual(&querybuf, qualsep,
1323 : paramname, pk_type,
1324 264 : riinfo->pf_eq_oprs[i],
1325 : attname, fk_type);
1326 264 : qualsep = "AND";
1327 264 : queryoids[i] = pk_type;
1328 : }
1329 :
1330 : /* Prepare and save the plan */
1331 148 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
1332 : &qkey, fk_rel, pk_rel);
1333 : }
1334 :
1335 : /*
1336 : * We have a plan now. Run it to update the existing references.
1337 : */
1338 260 : ri_PerformCheck(riinfo, &qkey, qplan,
1339 : fk_rel, pk_rel,
1340 : oldslot, NULL,
1341 : false,
1342 : true, /* must detect new rows */
1343 : SPI_OK_UPDATE);
1344 :
1345 258 : if (SPI_finish() != SPI_OK_FINISH)
1346 0 : elog(ERROR, "SPI_finish failed");
1347 :
1348 258 : table_close(fk_rel, RowExclusiveLock);
1349 :
1350 258 : if (is_set_null)
1351 126 : return PointerGetDatum(NULL);
1352 : else
1353 : {
1354 : /*
1355 : * If we just deleted or updated the PK row whose key was equal to the
1356 : * FK columns' default values, and a referencing row exists in the FK
1357 : * table, we would have updated that row to the same values it already
1358 : * had --- and RI_FKey_fk_upd_check_required would hence believe no
1359 : * check is necessary. So we need to do another lookup now and in
1360 : * case a reference still exists, abort the operation. That is
1361 : * already implemented in the NO ACTION trigger, so just run it. (This
1362 : * recheck is only needed in the SET DEFAULT case, since CASCADE would
1363 : * remove such rows in case of a DELETE operation or would change the
1364 : * FK key values in case of an UPDATE, while SET NULL is certain to
1365 : * result in rows that satisfy the FK constraint.)
1366 : */
1367 132 : return ri_restrict(trigdata, true);
1368 : }
1369 : }
1370 :
1371 :
1372 : /*
1373 : * RI_FKey_pk_upd_check_required -
1374 : *
1375 : * Check if we really need to fire the RI trigger for an update or delete to a PK
1376 : * relation. This is called by the AFTER trigger queue manager to see if
1377 : * it can skip queuing an instance of an RI trigger. Returns true if the
1378 : * trigger must be fired, false if we can prove the constraint will still
1379 : * be satisfied.
1380 : *
1381 : * newslot will be NULL if this is called for a delete.
1382 : */
1383 : bool
1384 2332 : RI_FKey_pk_upd_check_required(Trigger *trigger, Relation pk_rel,
1385 : TupleTableSlot *oldslot, TupleTableSlot *newslot)
1386 : {
1387 : const RI_ConstraintInfo *riinfo;
1388 :
1389 2332 : riinfo = ri_FetchConstraintInfo(trigger, pk_rel, true);
1390 :
1391 : /*
1392 : * If any old key value is NULL, the row could not have been referenced by
1393 : * an FK row, so no check is needed.
1394 : */
1395 2332 : if (ri_NullCheck(RelationGetDescr(pk_rel), oldslot, riinfo, true) != RI_KEYS_NONE_NULL)
1396 6 : return false;
1397 :
1398 : /* If all old and new key values are equal, no check is needed */
1399 2326 : if (newslot && ri_KeysEqual(pk_rel, oldslot, newslot, riinfo, true))
1400 536 : return false;
1401 :
1402 : /* Else we need to fire the trigger. */
1403 1790 : return true;
1404 : }
1405 :
1406 : /*
1407 : * RI_FKey_fk_upd_check_required -
1408 : *
1409 : * Check if we really need to fire the RI trigger for an update to an FK
1410 : * relation. This is called by the AFTER trigger queue manager to see if
1411 : * it can skip queuing an instance of an RI trigger. Returns true if the
1412 : * trigger must be fired, false if we can prove the constraint will still
1413 : * be satisfied.
1414 : */
1415 : bool
1416 1080 : RI_FKey_fk_upd_check_required(Trigger *trigger, Relation fk_rel,
1417 : TupleTableSlot *oldslot, TupleTableSlot *newslot)
1418 : {
1419 : const RI_ConstraintInfo *riinfo;
1420 : int ri_nullcheck;
1421 :
1422 : /*
1423 : * AfterTriggerSaveEvent() handles things such that this function is never
1424 : * called for partitioned tables.
1425 : */
1426 : Assert(fk_rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE);
1427 :
1428 1080 : riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1429 :
1430 1080 : ri_nullcheck = ri_NullCheck(RelationGetDescr(fk_rel), newslot, riinfo, false);
1431 :
1432 : /*
1433 : * If all new key values are NULL, the row satisfies the constraint, so no
1434 : * check is needed.
1435 : */
1436 1080 : if (ri_nullcheck == RI_KEYS_ALL_NULL)
1437 126 : return false;
1438 :
1439 : /*
1440 : * If some new key values are NULL, the behavior depends on the match
1441 : * type.
1442 : */
1443 954 : else if (ri_nullcheck == RI_KEYS_SOME_NULL)
1444 : {
1445 30 : switch (riinfo->confmatchtype)
1446 : {
1447 24 : case FKCONSTR_MATCH_SIMPLE:
1448 :
1449 : /*
1450 : * If any new key value is NULL, the row must satisfy the
1451 : * constraint, so no check is needed.
1452 : */
1453 24 : return false;
1454 :
1455 0 : case FKCONSTR_MATCH_PARTIAL:
1456 :
1457 : /*
1458 : * Don't know, must run full check.
1459 : */
1460 0 : break;
1461 :
1462 6 : case FKCONSTR_MATCH_FULL:
1463 :
1464 : /*
1465 : * If some new key values are NULL, the row fails the
1466 : * constraint. We must not throw error here, because the row
1467 : * might get invalidated before the constraint is to be
1468 : * checked, but we should queue the event to apply the check
1469 : * later.
1470 : */
1471 6 : return true;
1472 : }
1473 : }
1474 :
1475 : /*
1476 : * Continues here for no new key values are NULL, or we couldn't decide
1477 : * yet.
1478 : */
1479 :
1480 : /*
1481 : * If the original row was inserted by our own transaction, we must fire
1482 : * the trigger whether or not the keys are equal. This is because our
1483 : * UPDATE will invalidate the INSERT so that the INSERT RI trigger will
1484 : * not do anything; so we had better do the UPDATE check. (We could skip
1485 : * this if we knew the INSERT trigger already fired, but there is no easy
1486 : * way to know that.)
1487 : */
1488 924 : if (slot_is_current_xact_tuple(oldslot))
1489 124 : return true;
1490 :
1491 : /* If all old and new key values are equal, no check is needed */
1492 800 : if (ri_KeysEqual(fk_rel, oldslot, newslot, riinfo, false))
1493 464 : return false;
1494 :
1495 : /* Else we need to fire the trigger. */
1496 336 : return true;
1497 : }
1498 :
1499 : /*
1500 : * RI_Initial_Check -
1501 : *
1502 : * Check an entire table for non-matching values using a single query.
1503 : * This is not a trigger procedure, but is called during ALTER TABLE
1504 : * ADD FOREIGN KEY to validate the initial table contents.
1505 : *
1506 : * We expect that the caller has made provision to prevent any problems
1507 : * caused by concurrent actions. This could be either by locking rel and
1508 : * pkrel at ShareRowExclusiveLock or higher, or by otherwise ensuring
1509 : * that triggers implementing the checks are already active.
1510 : * Hence, we do not need to lock individual rows for the check.
1511 : *
1512 : * If the check fails because the current user doesn't have permissions
1513 : * to read both tables, return false to let our caller know that they will
1514 : * need to do something else to check the constraint.
1515 : */
1516 : bool
1517 1128 : RI_Initial_Check(Trigger *trigger, Relation fk_rel, Relation pk_rel)
1518 : {
1519 : const RI_ConstraintInfo *riinfo;
1520 : StringInfoData querybuf;
1521 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
1522 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1523 : char pkattname[MAX_QUOTED_NAME_LEN + 3];
1524 : char fkattname[MAX_QUOTED_NAME_LEN + 3];
1525 : RangeTblEntry *rte;
1526 : RTEPermissionInfo *pk_perminfo;
1527 : RTEPermissionInfo *fk_perminfo;
1528 1128 : List *rtes = NIL;
1529 1128 : List *perminfos = NIL;
1530 : const char *sep;
1531 : const char *fk_only;
1532 : const char *pk_only;
1533 : int save_nestlevel;
1534 : char workmembuf[32];
1535 : int spi_result;
1536 : SPIPlanPtr qplan;
1537 :
1538 1128 : riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1539 :
1540 : /*
1541 : * Check to make sure current user has enough permissions to do the test
1542 : * query. (If not, caller can fall back to the trigger method, which
1543 : * works because it changes user IDs on the fly.)
1544 : *
1545 : * XXX are there any other show-stopper conditions to check?
1546 : */
1547 1128 : pk_perminfo = makeNode(RTEPermissionInfo);
1548 1128 : pk_perminfo->relid = RelationGetRelid(pk_rel);
1549 1128 : pk_perminfo->requiredPerms = ACL_SELECT;
1550 1128 : perminfos = lappend(perminfos, pk_perminfo);
1551 1128 : rte = makeNode(RangeTblEntry);
1552 1128 : rte->rtekind = RTE_RELATION;
1553 1128 : rte->relid = RelationGetRelid(pk_rel);
1554 1128 : rte->relkind = pk_rel->rd_rel->relkind;
1555 1128 : rte->rellockmode = AccessShareLock;
1556 1128 : rte->perminfoindex = list_length(perminfos);
1557 1128 : rtes = lappend(rtes, rte);
1558 :
1559 1128 : fk_perminfo = makeNode(RTEPermissionInfo);
1560 1128 : fk_perminfo->relid = RelationGetRelid(fk_rel);
1561 1128 : fk_perminfo->requiredPerms = ACL_SELECT;
1562 1128 : perminfos = lappend(perminfos, fk_perminfo);
1563 1128 : rte = makeNode(RangeTblEntry);
1564 1128 : rte->rtekind = RTE_RELATION;
1565 1128 : rte->relid = RelationGetRelid(fk_rel);
1566 1128 : rte->relkind = fk_rel->rd_rel->relkind;
1567 1128 : rte->rellockmode = AccessShareLock;
1568 1128 : rte->perminfoindex = list_length(perminfos);
1569 1128 : rtes = lappend(rtes, rte);
1570 :
1571 2692 : for (int i = 0; i < riinfo->nkeys; i++)
1572 : {
1573 : int attno;
1574 :
1575 1564 : attno = riinfo->pk_attnums[i] - FirstLowInvalidHeapAttributeNumber;
1576 1564 : pk_perminfo->selectedCols = bms_add_member(pk_perminfo->selectedCols, attno);
1577 :
1578 1564 : attno = riinfo->fk_attnums[i] - FirstLowInvalidHeapAttributeNumber;
1579 1564 : fk_perminfo->selectedCols = bms_add_member(fk_perminfo->selectedCols, attno);
1580 : }
1581 :
1582 1128 : if (!ExecCheckPermissions(rtes, perminfos, false))
1583 12 : return false;
1584 :
1585 : /*
1586 : * Also punt if RLS is enabled on either table unless this role has the
1587 : * bypassrls right or is the table owner of the table(s) involved which
1588 : * have RLS enabled.
1589 : */
1590 1116 : if (!has_bypassrls_privilege(GetUserId()) &&
1591 0 : ((pk_rel->rd_rel->relrowsecurity &&
1592 0 : !object_ownercheck(RelationRelationId, RelationGetRelid(pk_rel),
1593 0 : GetUserId())) ||
1594 0 : (fk_rel->rd_rel->relrowsecurity &&
1595 0 : !object_ownercheck(RelationRelationId, RelationGetRelid(fk_rel),
1596 : GetUserId()))))
1597 0 : return false;
1598 :
1599 : /*----------
1600 : * The query string built is:
1601 : * SELECT fk.keycols FROM [ONLY] relname fk
1602 : * LEFT OUTER JOIN [ONLY] pkrelname pk
1603 : * ON (pk.pkkeycol1=fk.keycol1 [AND ...])
1604 : * WHERE pk.pkkeycol1 IS NULL AND
1605 : * For MATCH SIMPLE:
1606 : * (fk.keycol1 IS NOT NULL [AND ...])
1607 : * For MATCH FULL:
1608 : * (fk.keycol1 IS NOT NULL [OR ...])
1609 : *
1610 : * We attach COLLATE clauses to the operators when comparing columns
1611 : * that have different collations.
1612 : *----------
1613 : */
1614 1116 : initStringInfo(&querybuf);
1615 1116 : appendStringInfoString(&querybuf, "SELECT ");
1616 1116 : sep = "";
1617 2656 : for (int i = 0; i < riinfo->nkeys; i++)
1618 : {
1619 1540 : quoteOneName(fkattname,
1620 1540 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1621 1540 : appendStringInfo(&querybuf, "%sfk.%s", sep, fkattname);
1622 1540 : sep = ", ";
1623 : }
1624 :
1625 1116 : quoteRelationName(pkrelname, pk_rel);
1626 1116 : quoteRelationName(fkrelname, fk_rel);
1627 2232 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1628 1116 : "" : "ONLY ";
1629 2232 : pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1630 1116 : "" : "ONLY ";
1631 1116 : appendStringInfo(&querybuf,
1632 : " FROM %s%s fk LEFT OUTER JOIN %s%s pk ON",
1633 : fk_only, fkrelname, pk_only, pkrelname);
1634 :
1635 1116 : strcpy(pkattname, "pk.");
1636 1116 : strcpy(fkattname, "fk.");
1637 1116 : sep = "(";
1638 2656 : for (int i = 0; i < riinfo->nkeys; i++)
1639 : {
1640 1540 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1641 1540 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1642 1540 : Oid pk_coll = RIAttCollation(pk_rel, riinfo->pk_attnums[i]);
1643 1540 : Oid fk_coll = RIAttCollation(fk_rel, riinfo->fk_attnums[i]);
1644 :
1645 1540 : quoteOneName(pkattname + 3,
1646 1540 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
1647 1540 : quoteOneName(fkattname + 3,
1648 1540 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1649 1540 : ri_GenerateQual(&querybuf, sep,
1650 : pkattname, pk_type,
1651 1540 : riinfo->pf_eq_oprs[i],
1652 : fkattname, fk_type);
1653 1540 : if (pk_coll != fk_coll)
1654 12 : ri_GenerateQualCollation(&querybuf, pk_coll);
1655 1540 : sep = "AND";
1656 : }
1657 :
1658 : /*
1659 : * It's sufficient to test any one pk attribute for null to detect a join
1660 : * failure.
1661 : */
1662 1116 : quoteOneName(pkattname, RIAttName(pk_rel, riinfo->pk_attnums[0]));
1663 1116 : appendStringInfo(&querybuf, ") WHERE pk.%s IS NULL AND (", pkattname);
1664 :
1665 1116 : sep = "";
1666 2656 : for (int i = 0; i < riinfo->nkeys; i++)
1667 : {
1668 1540 : quoteOneName(fkattname, RIAttName(fk_rel, riinfo->fk_attnums[i]));
1669 1540 : appendStringInfo(&querybuf,
1670 : "%sfk.%s IS NOT NULL",
1671 : sep, fkattname);
1672 1540 : switch (riinfo->confmatchtype)
1673 : {
1674 1424 : case FKCONSTR_MATCH_SIMPLE:
1675 1424 : sep = " AND ";
1676 1424 : break;
1677 116 : case FKCONSTR_MATCH_FULL:
1678 116 : sep = " OR ";
1679 116 : break;
1680 : }
1681 : }
1682 1116 : appendStringInfoChar(&querybuf, ')');
1683 :
1684 : /*
1685 : * Temporarily increase work_mem so that the check query can be executed
1686 : * more efficiently. It seems okay to do this because the query is simple
1687 : * enough to not use a multiple of work_mem, and one typically would not
1688 : * have many large foreign-key validations happening concurrently. So
1689 : * this seems to meet the criteria for being considered a "maintenance"
1690 : * operation, and accordingly we use maintenance_work_mem. However, we
1691 : * must also set hash_mem_multiplier to 1, since it is surely not okay to
1692 : * let that get applied to the maintenance_work_mem value.
1693 : *
1694 : * We use the equivalent of a function SET option to allow the setting to
1695 : * persist for exactly the duration of the check query. guc.c also takes
1696 : * care of undoing the setting on error.
1697 : */
1698 1116 : save_nestlevel = NewGUCNestLevel();
1699 :
1700 1116 : snprintf(workmembuf, sizeof(workmembuf), "%d", maintenance_work_mem);
1701 1116 : (void) set_config_option("work_mem", workmembuf,
1702 : PGC_USERSET, PGC_S_SESSION,
1703 : GUC_ACTION_SAVE, true, 0, false);
1704 1116 : (void) set_config_option("hash_mem_multiplier", "1",
1705 : PGC_USERSET, PGC_S_SESSION,
1706 : GUC_ACTION_SAVE, true, 0, false);
1707 :
1708 1116 : SPI_connect();
1709 :
1710 : /*
1711 : * Generate the plan. We don't need to cache it, and there are no
1712 : * arguments to the plan.
1713 : */
1714 1116 : qplan = SPI_prepare(querybuf.data, 0, NULL);
1715 :
1716 1116 : if (qplan == NULL)
1717 0 : elog(ERROR, "SPI_prepare returned %s for %s",
1718 : SPI_result_code_string(SPI_result), querybuf.data);
1719 :
1720 : /*
1721 : * Run the plan. For safety we force a current snapshot to be used. (In
1722 : * transaction-snapshot mode, this arguably violates transaction isolation
1723 : * rules, but we really haven't got much choice.) We don't need to
1724 : * register the snapshot, because SPI_execute_snapshot will see to it. We
1725 : * need at most one tuple returned, so pass limit = 1.
1726 : */
1727 1116 : spi_result = SPI_execute_snapshot(qplan,
1728 : NULL, NULL,
1729 : GetLatestSnapshot(),
1730 : InvalidSnapshot,
1731 : true, false, 1);
1732 :
1733 : /* Check result */
1734 1116 : if (spi_result != SPI_OK_SELECT)
1735 0 : elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
1736 :
1737 : /* Did we find a tuple violating the constraint? */
1738 1116 : if (SPI_processed > 0)
1739 : {
1740 : TupleTableSlot *slot;
1741 74 : HeapTuple tuple = SPI_tuptable->vals[0];
1742 74 : TupleDesc tupdesc = SPI_tuptable->tupdesc;
1743 : RI_ConstraintInfo fake_riinfo;
1744 :
1745 74 : slot = MakeSingleTupleTableSlot(tupdesc, &TTSOpsVirtual);
1746 :
1747 74 : heap_deform_tuple(tuple, tupdesc,
1748 : slot->tts_values, slot->tts_isnull);
1749 74 : ExecStoreVirtualTuple(slot);
1750 :
1751 : /*
1752 : * The columns to look at in the result tuple are 1..N, not whatever
1753 : * they are in the fk_rel. Hack up riinfo so that the subroutines
1754 : * called here will behave properly.
1755 : *
1756 : * In addition to this, we have to pass the correct tupdesc to
1757 : * ri_ReportViolation, overriding its normal habit of using the pk_rel
1758 : * or fk_rel's tupdesc.
1759 : */
1760 74 : memcpy(&fake_riinfo, riinfo, sizeof(RI_ConstraintInfo));
1761 172 : for (int i = 0; i < fake_riinfo.nkeys; i++)
1762 98 : fake_riinfo.fk_attnums[i] = i + 1;
1763 :
1764 : /*
1765 : * If it's MATCH FULL, and there are any nulls in the FK keys,
1766 : * complain about that rather than the lack of a match. MATCH FULL
1767 : * disallows partially-null FK rows.
1768 : */
1769 104 : if (fake_riinfo.confmatchtype == FKCONSTR_MATCH_FULL &&
1770 30 : ri_NullCheck(tupdesc, slot, &fake_riinfo, false) != RI_KEYS_NONE_NULL)
1771 12 : ereport(ERROR,
1772 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
1773 : errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
1774 : RelationGetRelationName(fk_rel),
1775 : NameStr(fake_riinfo.conname)),
1776 : errdetail("MATCH FULL does not allow mixing of null and nonnull key values."),
1777 : errtableconstraint(fk_rel,
1778 : NameStr(fake_riinfo.conname))));
1779 :
1780 : /*
1781 : * We tell ri_ReportViolation we were doing the RI_PLAN_CHECK_LOOKUPPK
1782 : * query, which isn't true, but will cause it to use
1783 : * fake_riinfo.fk_attnums as we need.
1784 : */
1785 62 : ri_ReportViolation(&fake_riinfo,
1786 : pk_rel, fk_rel,
1787 : slot, tupdesc,
1788 : RI_PLAN_CHECK_LOOKUPPK, false, false);
1789 :
1790 : ExecDropSingleTupleTableSlot(slot);
1791 : }
1792 :
1793 1042 : if (SPI_finish() != SPI_OK_FINISH)
1794 0 : elog(ERROR, "SPI_finish failed");
1795 :
1796 : /*
1797 : * Restore work_mem and hash_mem_multiplier.
1798 : */
1799 1042 : AtEOXact_GUC(true, save_nestlevel);
1800 :
1801 1042 : return true;
1802 : }
1803 :
1804 : /*
1805 : * RI_PartitionRemove_Check -
1806 : *
1807 : * Verify no referencing values exist, when a partition is detached on
1808 : * the referenced side of a foreign key constraint.
1809 : */
1810 : void
1811 110 : RI_PartitionRemove_Check(Trigger *trigger, Relation fk_rel, Relation pk_rel)
1812 : {
1813 : const RI_ConstraintInfo *riinfo;
1814 : StringInfoData querybuf;
1815 : char *constraintDef;
1816 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
1817 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1818 : char pkattname[MAX_QUOTED_NAME_LEN + 3];
1819 : char fkattname[MAX_QUOTED_NAME_LEN + 3];
1820 : const char *sep;
1821 : const char *fk_only;
1822 : int save_nestlevel;
1823 : char workmembuf[32];
1824 : int spi_result;
1825 : SPIPlanPtr qplan;
1826 : int i;
1827 :
1828 110 : riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1829 :
1830 : /*
1831 : * We don't check permissions before displaying the error message, on the
1832 : * assumption that the user detaching the partition must have enough
1833 : * privileges to examine the table contents anyhow.
1834 : */
1835 :
1836 : /*----------
1837 : * The query string built is:
1838 : * SELECT fk.keycols FROM [ONLY] relname fk
1839 : * JOIN pkrelname pk
1840 : * ON (pk.pkkeycol1=fk.keycol1 [AND ...])
1841 : * WHERE (<partition constraint>) AND
1842 : * For MATCH SIMPLE:
1843 : * (fk.keycol1 IS NOT NULL [AND ...])
1844 : * For MATCH FULL:
1845 : * (fk.keycol1 IS NOT NULL [OR ...])
1846 : *
1847 : * We attach COLLATE clauses to the operators when comparing columns
1848 : * that have different collations.
1849 : *----------
1850 : */
1851 110 : initStringInfo(&querybuf);
1852 110 : appendStringInfoString(&querybuf, "SELECT ");
1853 110 : sep = "";
1854 220 : for (i = 0; i < riinfo->nkeys; i++)
1855 : {
1856 110 : quoteOneName(fkattname,
1857 110 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1858 110 : appendStringInfo(&querybuf, "%sfk.%s", sep, fkattname);
1859 110 : sep = ", ";
1860 : }
1861 :
1862 110 : quoteRelationName(pkrelname, pk_rel);
1863 110 : quoteRelationName(fkrelname, fk_rel);
1864 220 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1865 110 : "" : "ONLY ";
1866 110 : appendStringInfo(&querybuf,
1867 : " FROM %s%s fk JOIN %s pk ON",
1868 : fk_only, fkrelname, pkrelname);
1869 110 : strcpy(pkattname, "pk.");
1870 110 : strcpy(fkattname, "fk.");
1871 110 : sep = "(";
1872 220 : for (i = 0; i < riinfo->nkeys; i++)
1873 : {
1874 110 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1875 110 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1876 110 : Oid pk_coll = RIAttCollation(pk_rel, riinfo->pk_attnums[i]);
1877 110 : Oid fk_coll = RIAttCollation(fk_rel, riinfo->fk_attnums[i]);
1878 :
1879 110 : quoteOneName(pkattname + 3,
1880 110 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
1881 110 : quoteOneName(fkattname + 3,
1882 110 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1883 110 : ri_GenerateQual(&querybuf, sep,
1884 : pkattname, pk_type,
1885 110 : riinfo->pf_eq_oprs[i],
1886 : fkattname, fk_type);
1887 110 : if (pk_coll != fk_coll)
1888 0 : ri_GenerateQualCollation(&querybuf, pk_coll);
1889 110 : sep = "AND";
1890 : }
1891 :
1892 : /*
1893 : * Start the WHERE clause with the partition constraint (except if this is
1894 : * the default partition and there's no other partition, because the
1895 : * partition constraint is the empty string in that case.)
1896 : */
1897 110 : constraintDef = pg_get_partconstrdef_string(RelationGetRelid(pk_rel), "pk");
1898 110 : if (constraintDef && constraintDef[0] != '\0')
1899 110 : appendStringInfo(&querybuf, ") WHERE %s AND (",
1900 : constraintDef);
1901 : else
1902 0 : appendStringInfoString(&querybuf, ") WHERE (");
1903 :
1904 110 : sep = "";
1905 220 : for (i = 0; i < riinfo->nkeys; i++)
1906 : {
1907 110 : quoteOneName(fkattname, RIAttName(fk_rel, riinfo->fk_attnums[i]));
1908 110 : appendStringInfo(&querybuf,
1909 : "%sfk.%s IS NOT NULL",
1910 : sep, fkattname);
1911 110 : switch (riinfo->confmatchtype)
1912 : {
1913 110 : case FKCONSTR_MATCH_SIMPLE:
1914 110 : sep = " AND ";
1915 110 : break;
1916 0 : case FKCONSTR_MATCH_FULL:
1917 0 : sep = " OR ";
1918 0 : break;
1919 : }
1920 : }
1921 110 : appendStringInfoChar(&querybuf, ')');
1922 :
1923 : /*
1924 : * Temporarily increase work_mem so that the check query can be executed
1925 : * more efficiently. It seems okay to do this because the query is simple
1926 : * enough to not use a multiple of work_mem, and one typically would not
1927 : * have many large foreign-key validations happening concurrently. So
1928 : * this seems to meet the criteria for being considered a "maintenance"
1929 : * operation, and accordingly we use maintenance_work_mem. However, we
1930 : * must also set hash_mem_multiplier to 1, since it is surely not okay to
1931 : * let that get applied to the maintenance_work_mem value.
1932 : *
1933 : * We use the equivalent of a function SET option to allow the setting to
1934 : * persist for exactly the duration of the check query. guc.c also takes
1935 : * care of undoing the setting on error.
1936 : */
1937 110 : save_nestlevel = NewGUCNestLevel();
1938 :
1939 110 : snprintf(workmembuf, sizeof(workmembuf), "%d", maintenance_work_mem);
1940 110 : (void) set_config_option("work_mem", workmembuf,
1941 : PGC_USERSET, PGC_S_SESSION,
1942 : GUC_ACTION_SAVE, true, 0, false);
1943 110 : (void) set_config_option("hash_mem_multiplier", "1",
1944 : PGC_USERSET, PGC_S_SESSION,
1945 : GUC_ACTION_SAVE, true, 0, false);
1946 :
1947 110 : SPI_connect();
1948 :
1949 : /*
1950 : * Generate the plan. We don't need to cache it, and there are no
1951 : * arguments to the plan.
1952 : */
1953 110 : qplan = SPI_prepare(querybuf.data, 0, NULL);
1954 :
1955 110 : if (qplan == NULL)
1956 0 : elog(ERROR, "SPI_prepare returned %s for %s",
1957 : SPI_result_code_string(SPI_result), querybuf.data);
1958 :
1959 : /*
1960 : * Run the plan. For safety we force a current snapshot to be used. (In
1961 : * transaction-snapshot mode, this arguably violates transaction isolation
1962 : * rules, but we really haven't got much choice.) We don't need to
1963 : * register the snapshot, because SPI_execute_snapshot will see to it. We
1964 : * need at most one tuple returned, so pass limit = 1.
1965 : */
1966 110 : spi_result = SPI_execute_snapshot(qplan,
1967 : NULL, NULL,
1968 : GetLatestSnapshot(),
1969 : InvalidSnapshot,
1970 : true, false, 1);
1971 :
1972 : /* Check result */
1973 110 : if (spi_result != SPI_OK_SELECT)
1974 0 : elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
1975 :
1976 : /* Did we find a tuple that would violate the constraint? */
1977 110 : if (SPI_processed > 0)
1978 : {
1979 : TupleTableSlot *slot;
1980 34 : HeapTuple tuple = SPI_tuptable->vals[0];
1981 34 : TupleDesc tupdesc = SPI_tuptable->tupdesc;
1982 : RI_ConstraintInfo fake_riinfo;
1983 :
1984 34 : slot = MakeSingleTupleTableSlot(tupdesc, &TTSOpsVirtual);
1985 :
1986 34 : heap_deform_tuple(tuple, tupdesc,
1987 : slot->tts_values, slot->tts_isnull);
1988 34 : ExecStoreVirtualTuple(slot);
1989 :
1990 : /*
1991 : * The columns to look at in the result tuple are 1..N, not whatever
1992 : * they are in the fk_rel. Hack up riinfo so that ri_ReportViolation
1993 : * will behave properly.
1994 : *
1995 : * In addition to this, we have to pass the correct tupdesc to
1996 : * ri_ReportViolation, overriding its normal habit of using the pk_rel
1997 : * or fk_rel's tupdesc.
1998 : */
1999 34 : memcpy(&fake_riinfo, riinfo, sizeof(RI_ConstraintInfo));
2000 68 : for (i = 0; i < fake_riinfo.nkeys; i++)
2001 34 : fake_riinfo.pk_attnums[i] = i + 1;
2002 :
2003 34 : ri_ReportViolation(&fake_riinfo, pk_rel, fk_rel,
2004 : slot, tupdesc, 0, false, true);
2005 : }
2006 :
2007 76 : if (SPI_finish() != SPI_OK_FINISH)
2008 0 : elog(ERROR, "SPI_finish failed");
2009 :
2010 : /*
2011 : * Restore work_mem and hash_mem_multiplier.
2012 : */
2013 76 : AtEOXact_GUC(true, save_nestlevel);
2014 76 : }
2015 :
2016 :
2017 : /* ----------
2018 : * Local functions below
2019 : * ----------
2020 : */
2021 :
2022 :
2023 : /*
2024 : * quoteOneName --- safely quote a single SQL name
2025 : *
2026 : * buffer must be MAX_QUOTED_NAME_LEN long (includes room for \0)
2027 : */
2028 : static void
2029 24490 : quoteOneName(char *buffer, const char *name)
2030 : {
2031 : /* Rather than trying to be smart, just always quote it. */
2032 24490 : *buffer++ = '"';
2033 153418 : while (*name)
2034 : {
2035 128928 : if (*name == '"')
2036 0 : *buffer++ = '"';
2037 128928 : *buffer++ = *name++;
2038 : }
2039 24490 : *buffer++ = '"';
2040 24490 : *buffer = '\0';
2041 24490 : }
2042 :
2043 : /*
2044 : * quoteRelationName --- safely quote a fully qualified relation name
2045 : *
2046 : * buffer must be MAX_QUOTED_REL_NAME_LEN long (includes room for \0)
2047 : */
2048 : static void
2049 5914 : quoteRelationName(char *buffer, Relation rel)
2050 : {
2051 5914 : quoteOneName(buffer, get_namespace_name(RelationGetNamespace(rel)));
2052 5914 : buffer += strlen(buffer);
2053 5914 : *buffer++ = '.';
2054 5914 : quoteOneName(buffer, RelationGetRelationName(rel));
2055 5914 : }
2056 :
2057 : /*
2058 : * ri_GenerateQual --- generate a WHERE clause equating two variables
2059 : *
2060 : * This basically appends " sep leftop op rightop" to buf, adding casts
2061 : * and schema qualification as needed to ensure that the parser will select
2062 : * the operator we specify. leftop and rightop should be parenthesized
2063 : * if they aren't variables or parameters.
2064 : */
2065 : static void
2066 6332 : ri_GenerateQual(StringInfo buf,
2067 : const char *sep,
2068 : const char *leftop, Oid leftoptype,
2069 : Oid opoid,
2070 : const char *rightop, Oid rightoptype)
2071 : {
2072 6332 : appendStringInfo(buf, " %s ", sep);
2073 6332 : generate_operator_clause(buf, leftop, leftoptype, opoid,
2074 : rightop, rightoptype);
2075 6332 : }
2076 :
2077 : /*
2078 : * ri_GenerateQualCollation --- add a COLLATE spec to a WHERE clause
2079 : *
2080 : * We only have to use this function when directly comparing the referencing
2081 : * and referenced columns, if they are of different collations; else the
2082 : * parser will fail to resolve the collation to use. We don't need to use
2083 : * this function for RI queries that compare a variable to a $n parameter.
2084 : * Since parameter symbols always have default collation, the effect will be
2085 : * to use the variable's collation.
2086 : *
2087 : * Note that we require that the collations of the referencing and the
2088 : * referenced column have the same notion of equality: Either they have to
2089 : * both be deterministic or else they both have to be the same. (See also
2090 : * ATAddForeignKeyConstraint().)
2091 : */
2092 : static void
2093 12 : ri_GenerateQualCollation(StringInfo buf, Oid collation)
2094 : {
2095 : HeapTuple tp;
2096 : Form_pg_collation colltup;
2097 : char *collname;
2098 : char onename[MAX_QUOTED_NAME_LEN];
2099 :
2100 : /* Nothing to do if it's a noncollatable data type */
2101 12 : if (!OidIsValid(collation))
2102 0 : return;
2103 :
2104 12 : tp = SearchSysCache1(COLLOID, ObjectIdGetDatum(collation));
2105 12 : if (!HeapTupleIsValid(tp))
2106 0 : elog(ERROR, "cache lookup failed for collation %u", collation);
2107 12 : colltup = (Form_pg_collation) GETSTRUCT(tp);
2108 12 : collname = NameStr(colltup->collname);
2109 :
2110 : /*
2111 : * We qualify the name always, for simplicity and to ensure the query is
2112 : * not search-path-dependent.
2113 : */
2114 12 : quoteOneName(onename, get_namespace_name(colltup->collnamespace));
2115 12 : appendStringInfo(buf, " COLLATE %s", onename);
2116 12 : quoteOneName(onename, collname);
2117 12 : appendStringInfo(buf, ".%s", onename);
2118 :
2119 12 : ReleaseSysCache(tp);
2120 : }
2121 :
2122 : /* ----------
2123 : * ri_BuildQueryKey -
2124 : *
2125 : * Construct a hashtable key for a prepared SPI plan of an FK constraint.
2126 : *
2127 : * key: output argument, *key is filled in based on the other arguments
2128 : * riinfo: info derived from pg_constraint entry
2129 : * constr_queryno: an internal number identifying the query type
2130 : * (see RI_PLAN_XXX constants at head of file)
2131 : * ----------
2132 : */
2133 : static void
2134 6600 : ri_BuildQueryKey(RI_QueryKey *key, const RI_ConstraintInfo *riinfo,
2135 : int32 constr_queryno)
2136 : {
2137 : /*
2138 : * Inherited constraints with a common ancestor can share ri_query_cache
2139 : * entries for all query types except RI_PLAN_CHECK_LOOKUPPK_FROM_PK.
2140 : * Except in that case, the query processes the other table involved in
2141 : * the FK constraint (i.e., not the table on which the trigger has been
2142 : * fired), and so it will be the same for all members of the inheritance
2143 : * tree. So we may use the root constraint's OID in the hash key, rather
2144 : * than the constraint's own OID. This avoids creating duplicate SPI
2145 : * plans, saving lots of work and memory when there are many partitions
2146 : * with similar FK constraints.
2147 : *
2148 : * (Note that we must still have a separate RI_ConstraintInfo for each
2149 : * constraint, because partitions can have different column orders,
2150 : * resulting in different pk_attnums[] or fk_attnums[] array contents.)
2151 : *
2152 : * We assume struct RI_QueryKey contains no padding bytes, else we'd need
2153 : * to use memset to clear them.
2154 : */
2155 6600 : if (constr_queryno != RI_PLAN_CHECK_LOOKUPPK_FROM_PK)
2156 5814 : key->constr_id = riinfo->constraint_root_id;
2157 : else
2158 786 : key->constr_id = riinfo->constraint_id;
2159 6600 : key->constr_queryno = constr_queryno;
2160 6600 : }
2161 :
2162 : /*
2163 : * Check that RI trigger function was called in expected context
2164 : */
2165 : static void
2166 6114 : ri_CheckTrigger(FunctionCallInfo fcinfo, const char *funcname, int tgkind)
2167 : {
2168 6114 : TriggerData *trigdata = (TriggerData *) fcinfo->context;
2169 :
2170 6114 : if (!CALLED_AS_TRIGGER(fcinfo))
2171 0 : ereport(ERROR,
2172 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2173 : errmsg("function \"%s\" was not called by trigger manager", funcname)));
2174 :
2175 : /*
2176 : * Check proper event
2177 : */
2178 6114 : if (!TRIGGER_FIRED_AFTER(trigdata->tg_event) ||
2179 6114 : !TRIGGER_FIRED_FOR_ROW(trigdata->tg_event))
2180 0 : ereport(ERROR,
2181 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2182 : errmsg("function \"%s\" must be fired AFTER ROW", funcname)));
2183 :
2184 6114 : switch (tgkind)
2185 : {
2186 4070 : case RI_TRIGTYPE_INSERT:
2187 4070 : if (!TRIGGER_FIRED_BY_INSERT(trigdata->tg_event))
2188 0 : ereport(ERROR,
2189 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2190 : errmsg("function \"%s\" must be fired for INSERT", funcname)));
2191 4070 : break;
2192 1252 : case RI_TRIGTYPE_UPDATE:
2193 1252 : if (!TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
2194 0 : ereport(ERROR,
2195 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2196 : errmsg("function \"%s\" must be fired for UPDATE", funcname)));
2197 1252 : break;
2198 792 : case RI_TRIGTYPE_DELETE:
2199 792 : if (!TRIGGER_FIRED_BY_DELETE(trigdata->tg_event))
2200 0 : ereport(ERROR,
2201 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2202 : errmsg("function \"%s\" must be fired for DELETE", funcname)));
2203 792 : break;
2204 : }
2205 6114 : }
2206 :
2207 :
2208 : /*
2209 : * Fetch the RI_ConstraintInfo struct for the trigger's FK constraint.
2210 : */
2211 : static const RI_ConstraintInfo *
2212 10896 : ri_FetchConstraintInfo(Trigger *trigger, Relation trig_rel, bool rel_is_pk)
2213 : {
2214 10896 : Oid constraintOid = trigger->tgconstraint;
2215 : const RI_ConstraintInfo *riinfo;
2216 :
2217 : /*
2218 : * Check that the FK constraint's OID is available; it might not be if
2219 : * we've been invoked via an ordinary trigger or an old-style "constraint
2220 : * trigger".
2221 : */
2222 10896 : if (!OidIsValid(constraintOid))
2223 0 : ereport(ERROR,
2224 : (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
2225 : errmsg("no pg_constraint entry for trigger \"%s\" on table \"%s\"",
2226 : trigger->tgname, RelationGetRelationName(trig_rel)),
2227 : errhint("Remove this referential integrity trigger and its mates, then do ALTER TABLE ADD CONSTRAINT.")));
2228 :
2229 : /* Find or create a hashtable entry for the constraint */
2230 10896 : riinfo = ri_LoadConstraintInfo(constraintOid);
2231 :
2232 : /* Do some easy cross-checks against the trigger call data */
2233 10896 : if (rel_is_pk)
2234 : {
2235 4060 : if (riinfo->fk_relid != trigger->tgconstrrelid ||
2236 4060 : riinfo->pk_relid != RelationGetRelid(trig_rel))
2237 0 : elog(ERROR, "wrong pg_constraint entry for trigger \"%s\" on table \"%s\"",
2238 : trigger->tgname, RelationGetRelationName(trig_rel));
2239 : }
2240 : else
2241 : {
2242 6836 : if (riinfo->fk_relid != RelationGetRelid(trig_rel) ||
2243 6836 : riinfo->pk_relid != trigger->tgconstrrelid)
2244 0 : elog(ERROR, "wrong pg_constraint entry for trigger \"%s\" on table \"%s\"",
2245 : trigger->tgname, RelationGetRelationName(trig_rel));
2246 : }
2247 :
2248 10896 : if (riinfo->confmatchtype != FKCONSTR_MATCH_FULL &&
2249 10424 : riinfo->confmatchtype != FKCONSTR_MATCH_PARTIAL &&
2250 10424 : riinfo->confmatchtype != FKCONSTR_MATCH_SIMPLE)
2251 0 : elog(ERROR, "unrecognized confmatchtype: %d",
2252 : riinfo->confmatchtype);
2253 :
2254 10896 : if (riinfo->confmatchtype == FKCONSTR_MATCH_PARTIAL)
2255 0 : ereport(ERROR,
2256 : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2257 : errmsg("MATCH PARTIAL not yet implemented")));
2258 :
2259 10896 : return riinfo;
2260 : }
2261 :
2262 : /*
2263 : * Fetch or create the RI_ConstraintInfo struct for an FK constraint.
2264 : */
2265 : static const RI_ConstraintInfo *
2266 10896 : ri_LoadConstraintInfo(Oid constraintOid)
2267 : {
2268 : RI_ConstraintInfo *riinfo;
2269 : bool found;
2270 : HeapTuple tup;
2271 : Form_pg_constraint conForm;
2272 :
2273 : /*
2274 : * On the first call initialize the hashtable
2275 : */
2276 10896 : if (!ri_constraint_cache)
2277 426 : ri_InitHashTables();
2278 :
2279 : /*
2280 : * Find or create a hash entry. If we find a valid one, just return it.
2281 : */
2282 10896 : riinfo = (RI_ConstraintInfo *) hash_search(ri_constraint_cache,
2283 : &constraintOid,
2284 : HASH_ENTER, &found);
2285 10896 : if (!found)
2286 3968 : riinfo->valid = false;
2287 6928 : else if (riinfo->valid)
2288 6606 : return riinfo;
2289 :
2290 : /*
2291 : * Fetch the pg_constraint row so we can fill in the entry.
2292 : */
2293 4290 : tup = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constraintOid));
2294 4290 : if (!HeapTupleIsValid(tup)) /* should not happen */
2295 0 : elog(ERROR, "cache lookup failed for constraint %u", constraintOid);
2296 4290 : conForm = (Form_pg_constraint) GETSTRUCT(tup);
2297 :
2298 4290 : if (conForm->contype != CONSTRAINT_FOREIGN) /* should not happen */
2299 0 : elog(ERROR, "constraint %u is not a foreign key constraint",
2300 : constraintOid);
2301 :
2302 : /* And extract data */
2303 : Assert(riinfo->constraint_id == constraintOid);
2304 4290 : if (OidIsValid(conForm->conparentid))
2305 1564 : riinfo->constraint_root_id =
2306 1564 : get_ri_constraint_root(conForm->conparentid);
2307 : else
2308 2726 : riinfo->constraint_root_id = constraintOid;
2309 4290 : riinfo->oidHashValue = GetSysCacheHashValue1(CONSTROID,
2310 : ObjectIdGetDatum(constraintOid));
2311 4290 : riinfo->rootHashValue = GetSysCacheHashValue1(CONSTROID,
2312 : ObjectIdGetDatum(riinfo->constraint_root_id));
2313 4290 : memcpy(&riinfo->conname, &conForm->conname, sizeof(NameData));
2314 4290 : riinfo->pk_relid = conForm->confrelid;
2315 4290 : riinfo->fk_relid = conForm->conrelid;
2316 4290 : riinfo->confupdtype = conForm->confupdtype;
2317 4290 : riinfo->confdeltype = conForm->confdeltype;
2318 4290 : riinfo->confmatchtype = conForm->confmatchtype;
2319 4290 : riinfo->hasperiod = conForm->conperiod;
2320 :
2321 4290 : DeconstructFkConstraintRow(tup,
2322 : &riinfo->nkeys,
2323 4290 : riinfo->fk_attnums,
2324 4290 : riinfo->pk_attnums,
2325 4290 : riinfo->pf_eq_oprs,
2326 4290 : riinfo->pp_eq_oprs,
2327 4290 : riinfo->ff_eq_oprs,
2328 : &riinfo->ndelsetcols,
2329 4290 : riinfo->confdelsetcols);
2330 :
2331 : /*
2332 : * For temporal FKs, get the operators and functions we need. We ask the
2333 : * opclass of the PK element for these. This all gets cached (as does the
2334 : * generated plan), so there's no performance issue.
2335 : */
2336 4290 : if (riinfo->hasperiod)
2337 : {
2338 154 : Oid opclass = get_index_column_opclass(conForm->conindid, riinfo->nkeys);
2339 :
2340 154 : FindFKPeriodOpers(opclass,
2341 : &riinfo->period_contained_by_oper,
2342 : &riinfo->agged_period_contained_by_oper,
2343 : &riinfo->period_intersect_oper);
2344 : }
2345 :
2346 4290 : ReleaseSysCache(tup);
2347 :
2348 : /*
2349 : * For efficient processing of invalidation messages below, we keep a
2350 : * doubly-linked count list of all currently valid entries.
2351 : */
2352 4290 : dclist_push_tail(&ri_constraint_cache_valid_list, &riinfo->valid_link);
2353 :
2354 4290 : riinfo->valid = true;
2355 :
2356 4290 : return riinfo;
2357 : }
2358 :
2359 : /*
2360 : * get_ri_constraint_root
2361 : * Returns the OID of the constraint's root parent
2362 : */
2363 : static Oid
2364 1564 : get_ri_constraint_root(Oid constrOid)
2365 : {
2366 : for (;;)
2367 366 : {
2368 : HeapTuple tuple;
2369 : Oid constrParentOid;
2370 :
2371 1930 : tuple = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constrOid));
2372 1930 : if (!HeapTupleIsValid(tuple))
2373 0 : elog(ERROR, "cache lookup failed for constraint %u", constrOid);
2374 1930 : constrParentOid = ((Form_pg_constraint) GETSTRUCT(tuple))->conparentid;
2375 1930 : ReleaseSysCache(tuple);
2376 1930 : if (!OidIsValid(constrParentOid))
2377 1564 : break; /* we reached the root constraint */
2378 366 : constrOid = constrParentOid;
2379 : }
2380 1564 : return constrOid;
2381 : }
2382 :
2383 : /*
2384 : * Callback for pg_constraint inval events
2385 : *
2386 : * While most syscache callbacks just flush all their entries, pg_constraint
2387 : * gets enough update traffic that it's probably worth being smarter.
2388 : * Invalidate any ri_constraint_cache entry associated with the syscache
2389 : * entry with the specified hash value, or all entries if hashvalue == 0.
2390 : *
2391 : * Note: at the time a cache invalidation message is processed there may be
2392 : * active references to the cache. Because of this we never remove entries
2393 : * from the cache, but only mark them invalid, which is harmless to active
2394 : * uses. (Any query using an entry should hold a lock sufficient to keep that
2395 : * data from changing under it --- but we may get cache flushes anyway.)
2396 : */
2397 : static void
2398 80136 : InvalidateConstraintCacheCallBack(Datum arg, int cacheid, uint32 hashvalue)
2399 : {
2400 : dlist_mutable_iter iter;
2401 :
2402 : Assert(ri_constraint_cache != NULL);
2403 :
2404 : /*
2405 : * If the list of currently valid entries gets excessively large, we mark
2406 : * them all invalid so we can empty the list. This arrangement avoids
2407 : * O(N^2) behavior in situations where a session touches many foreign keys
2408 : * and also does many ALTER TABLEs, such as a restore from pg_dump.
2409 : */
2410 80136 : if (dclist_count(&ri_constraint_cache_valid_list) > 1000)
2411 0 : hashvalue = 0; /* pretend it's a cache reset */
2412 :
2413 309202 : dclist_foreach_modify(iter, &ri_constraint_cache_valid_list)
2414 : {
2415 229066 : RI_ConstraintInfo *riinfo = dclist_container(RI_ConstraintInfo,
2416 : valid_link, iter.cur);
2417 :
2418 : /*
2419 : * We must invalidate not only entries directly matching the given
2420 : * hash value, but also child entries, in case the invalidation
2421 : * affects a root constraint.
2422 : */
2423 229066 : if (hashvalue == 0 ||
2424 229008 : riinfo->oidHashValue == hashvalue ||
2425 226450 : riinfo->rootHashValue == hashvalue)
2426 : {
2427 2942 : riinfo->valid = false;
2428 : /* Remove invalidated entries from the list, too */
2429 2942 : dclist_delete_from(&ri_constraint_cache_valid_list, iter.cur);
2430 : }
2431 : }
2432 80136 : }
2433 :
2434 :
2435 : /*
2436 : * Prepare execution plan for a query to enforce an RI restriction
2437 : */
2438 : static SPIPlanPtr
2439 3358 : ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
2440 : RI_QueryKey *qkey, Relation fk_rel, Relation pk_rel)
2441 : {
2442 : SPIPlanPtr qplan;
2443 : Relation query_rel;
2444 : Oid save_userid;
2445 : int save_sec_context;
2446 :
2447 : /*
2448 : * Use the query type code to determine whether the query is run against
2449 : * the PK or FK table; we'll do the check as that table's owner
2450 : */
2451 3358 : if (qkey->constr_queryno <= RI_PLAN_LAST_ON_PK)
2452 2560 : query_rel = pk_rel;
2453 : else
2454 798 : query_rel = fk_rel;
2455 :
2456 : /* Switch to proper UID to perform check as */
2457 3358 : GetUserIdAndSecContext(&save_userid, &save_sec_context);
2458 3358 : SetUserIdAndSecContext(RelationGetForm(query_rel)->relowner,
2459 : save_sec_context | SECURITY_LOCAL_USERID_CHANGE |
2460 : SECURITY_NOFORCE_RLS);
2461 :
2462 : /* Create the plan */
2463 3358 : qplan = SPI_prepare(querystr, nargs, argtypes);
2464 :
2465 3358 : if (qplan == NULL)
2466 0 : elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), querystr);
2467 :
2468 : /* Restore UID and security context */
2469 3358 : SetUserIdAndSecContext(save_userid, save_sec_context);
2470 :
2471 : /* Save the plan */
2472 3358 : SPI_keepplan(qplan);
2473 3358 : ri_HashPreparedPlan(qkey, qplan);
2474 :
2475 3358 : return qplan;
2476 : }
2477 :
2478 : /*
2479 : * Perform a query to enforce an RI restriction
2480 : */
2481 : static bool
2482 6600 : ri_PerformCheck(const RI_ConstraintInfo *riinfo,
2483 : RI_QueryKey *qkey, SPIPlanPtr qplan,
2484 : Relation fk_rel, Relation pk_rel,
2485 : TupleTableSlot *oldslot, TupleTableSlot *newslot,
2486 : bool is_restrict,
2487 : bool detectNewRows, int expect_OK)
2488 : {
2489 : Relation query_rel,
2490 : source_rel;
2491 : bool source_is_pk;
2492 : Snapshot test_snapshot;
2493 : Snapshot crosscheck_snapshot;
2494 : int limit;
2495 : int spi_result;
2496 : Oid save_userid;
2497 : int save_sec_context;
2498 : Datum vals[RI_MAX_NUMKEYS * 2];
2499 : char nulls[RI_MAX_NUMKEYS * 2];
2500 :
2501 : /*
2502 : * Use the query type code to determine whether the query is run against
2503 : * the PK or FK table; we'll do the check as that table's owner
2504 : */
2505 6600 : if (qkey->constr_queryno <= RI_PLAN_LAST_ON_PK)
2506 4930 : query_rel = pk_rel;
2507 : else
2508 1670 : query_rel = fk_rel;
2509 :
2510 : /*
2511 : * The values for the query are taken from the table on which the trigger
2512 : * is called - it is normally the other one with respect to query_rel. An
2513 : * exception is ri_Check_Pk_Match(), which uses the PK table for both (and
2514 : * sets queryno to RI_PLAN_CHECK_LOOKUPPK_FROM_PK). We might eventually
2515 : * need some less klugy way to determine this.
2516 : */
2517 6600 : if (qkey->constr_queryno == RI_PLAN_CHECK_LOOKUPPK)
2518 : {
2519 4144 : source_rel = fk_rel;
2520 4144 : source_is_pk = false;
2521 : }
2522 : else
2523 : {
2524 2456 : source_rel = pk_rel;
2525 2456 : source_is_pk = true;
2526 : }
2527 :
2528 : /* Extract the parameters to be passed into the query */
2529 6600 : if (newslot)
2530 : {
2531 4348 : ri_ExtractValues(source_rel, newslot, riinfo, source_is_pk,
2532 : vals, nulls);
2533 4348 : if (oldslot)
2534 204 : ri_ExtractValues(source_rel, oldslot, riinfo, source_is_pk,
2535 204 : vals + riinfo->nkeys, nulls + riinfo->nkeys);
2536 : }
2537 : else
2538 : {
2539 2252 : ri_ExtractValues(source_rel, oldslot, riinfo, source_is_pk,
2540 : vals, nulls);
2541 : }
2542 :
2543 : /*
2544 : * In READ COMMITTED mode, we just need to use an up-to-date regular
2545 : * snapshot, and we will see all rows that could be interesting. But in
2546 : * transaction-snapshot mode, we can't change the transaction snapshot. If
2547 : * the caller passes detectNewRows == false then it's okay to do the query
2548 : * with the transaction snapshot; otherwise we use a current snapshot, and
2549 : * tell the executor to error out if it finds any rows under the current
2550 : * snapshot that wouldn't be visible per the transaction snapshot. Note
2551 : * that SPI_execute_snapshot will register the snapshots, so we don't need
2552 : * to bother here.
2553 : */
2554 6600 : if (IsolationUsesXactSnapshot() && detectNewRows)
2555 : {
2556 32 : CommandCounterIncrement(); /* be sure all my own work is visible */
2557 32 : test_snapshot = GetLatestSnapshot();
2558 32 : crosscheck_snapshot = GetTransactionSnapshot();
2559 : }
2560 : else
2561 : {
2562 : /* the default SPI behavior is okay */
2563 6568 : test_snapshot = InvalidSnapshot;
2564 6568 : crosscheck_snapshot = InvalidSnapshot;
2565 : }
2566 :
2567 : /*
2568 : * If this is a select query (e.g., for a 'no action' or 'restrict'
2569 : * trigger), we only need to see if there is a single row in the table,
2570 : * matching the key. Otherwise, limit = 0 - because we want the query to
2571 : * affect ALL the matching rows.
2572 : */
2573 6600 : limit = (expect_OK == SPI_OK_SELECT) ? 1 : 0;
2574 :
2575 : /* Switch to proper UID to perform check as */
2576 6600 : GetUserIdAndSecContext(&save_userid, &save_sec_context);
2577 6600 : SetUserIdAndSecContext(RelationGetForm(query_rel)->relowner,
2578 : save_sec_context | SECURITY_LOCAL_USERID_CHANGE |
2579 : SECURITY_NOFORCE_RLS);
2580 :
2581 : /* Finally we can run the query. */
2582 6600 : spi_result = SPI_execute_snapshot(qplan,
2583 : vals, nulls,
2584 : test_snapshot, crosscheck_snapshot,
2585 : false, false, limit);
2586 :
2587 : /* Restore UID and security context */
2588 6586 : SetUserIdAndSecContext(save_userid, save_sec_context);
2589 :
2590 : /* Check result */
2591 6586 : if (spi_result < 0)
2592 0 : elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
2593 :
2594 6586 : if (expect_OK >= 0 && spi_result != expect_OK)
2595 0 : ereport(ERROR,
2596 : (errcode(ERRCODE_INTERNAL_ERROR),
2597 : errmsg("referential integrity query on \"%s\" from constraint \"%s\" on \"%s\" gave unexpected result",
2598 : RelationGetRelationName(pk_rel),
2599 : NameStr(riinfo->conname),
2600 : RelationGetRelationName(fk_rel)),
2601 : errhint("This is most likely due to a rule having rewritten the query.")));
2602 :
2603 : /* XXX wouldn't it be clearer to do this part at the caller? */
2604 6586 : if (qkey->constr_queryno != RI_PLAN_CHECK_LOOKUPPK_FROM_PK &&
2605 5192 : expect_OK == SPI_OK_SELECT &&
2606 5192 : (SPI_processed == 0) == (qkey->constr_queryno == RI_PLAN_CHECK_LOOKUPPK))
2607 1034 : ri_ReportViolation(riinfo,
2608 : pk_rel, fk_rel,
2609 : newslot ? newslot : oldslot,
2610 : NULL,
2611 : qkey->constr_queryno, is_restrict, false);
2612 :
2613 5552 : return SPI_processed != 0;
2614 : }
2615 :
2616 : /*
2617 : * Extract fields from a tuple into Datum/nulls arrays
2618 : */
2619 : static void
2620 6804 : ri_ExtractValues(Relation rel, TupleTableSlot *slot,
2621 : const RI_ConstraintInfo *riinfo, bool rel_is_pk,
2622 : Datum *vals, char *nulls)
2623 : {
2624 : const int16 *attnums;
2625 : bool isnull;
2626 :
2627 6804 : if (rel_is_pk)
2628 2660 : attnums = riinfo->pk_attnums;
2629 : else
2630 4144 : attnums = riinfo->fk_attnums;
2631 :
2632 15892 : for (int i = 0; i < riinfo->nkeys; i++)
2633 : {
2634 9088 : vals[i] = slot_getattr(slot, attnums[i], &isnull);
2635 9088 : nulls[i] = isnull ? 'n' : ' ';
2636 : }
2637 6804 : }
2638 :
2639 : /*
2640 : * Produce an error report
2641 : *
2642 : * If the failed constraint was on insert/update to the FK table,
2643 : * we want the key names and values extracted from there, and the error
2644 : * message to look like 'key blah is not present in PK'.
2645 : * Otherwise, the attr names and values come from the PK table and the
2646 : * message looks like 'key blah is still referenced from FK'.
2647 : */
2648 : static void
2649 1130 : ri_ReportViolation(const RI_ConstraintInfo *riinfo,
2650 : Relation pk_rel, Relation fk_rel,
2651 : TupleTableSlot *violatorslot, TupleDesc tupdesc,
2652 : int queryno, bool is_restrict, bool partgone)
2653 : {
2654 : StringInfoData key_names;
2655 : StringInfoData key_values;
2656 : bool onfk;
2657 : const int16 *attnums;
2658 : Oid rel_oid;
2659 : AclResult aclresult;
2660 1130 : bool has_perm = true;
2661 :
2662 : /*
2663 : * Determine which relation to complain about. If tupdesc wasn't passed
2664 : * by caller, assume the violator tuple came from there.
2665 : */
2666 1130 : onfk = (queryno == RI_PLAN_CHECK_LOOKUPPK);
2667 1130 : if (onfk)
2668 : {
2669 630 : attnums = riinfo->fk_attnums;
2670 630 : rel_oid = fk_rel->rd_id;
2671 630 : if (tupdesc == NULL)
2672 568 : tupdesc = fk_rel->rd_att;
2673 : }
2674 : else
2675 : {
2676 500 : attnums = riinfo->pk_attnums;
2677 500 : rel_oid = pk_rel->rd_id;
2678 500 : if (tupdesc == NULL)
2679 466 : tupdesc = pk_rel->rd_att;
2680 : }
2681 :
2682 : /*
2683 : * Check permissions- if the user does not have access to view the data in
2684 : * any of the key columns then we don't include the errdetail() below.
2685 : *
2686 : * Check if RLS is enabled on the relation first. If so, we don't return
2687 : * any specifics to avoid leaking data.
2688 : *
2689 : * Check table-level permissions next and, failing that, column-level
2690 : * privileges.
2691 : *
2692 : * When a partition at the referenced side is being detached/dropped, we
2693 : * needn't check, since the user must be the table owner anyway.
2694 : */
2695 1130 : if (partgone)
2696 34 : has_perm = true;
2697 1096 : else if (check_enable_rls(rel_oid, InvalidOid, true) != RLS_ENABLED)
2698 : {
2699 1090 : aclresult = pg_class_aclcheck(rel_oid, GetUserId(), ACL_SELECT);
2700 1090 : if (aclresult != ACLCHECK_OK)
2701 : {
2702 : /* Try for column-level permissions */
2703 0 : for (int idx = 0; idx < riinfo->nkeys; idx++)
2704 : {
2705 0 : aclresult = pg_attribute_aclcheck(rel_oid, attnums[idx],
2706 : GetUserId(),
2707 : ACL_SELECT);
2708 :
2709 : /* No access to the key */
2710 0 : if (aclresult != ACLCHECK_OK)
2711 : {
2712 0 : has_perm = false;
2713 0 : break;
2714 : }
2715 : }
2716 : }
2717 : }
2718 : else
2719 6 : has_perm = false;
2720 :
2721 1130 : if (has_perm)
2722 : {
2723 : /* Get printable versions of the keys involved */
2724 1124 : initStringInfo(&key_names);
2725 1124 : initStringInfo(&key_values);
2726 2770 : for (int idx = 0; idx < riinfo->nkeys; idx++)
2727 : {
2728 1646 : int fnum = attnums[idx];
2729 1646 : Form_pg_attribute att = TupleDescAttr(tupdesc, fnum - 1);
2730 : char *name,
2731 : *val;
2732 : Datum datum;
2733 : bool isnull;
2734 :
2735 1646 : name = NameStr(att->attname);
2736 :
2737 1646 : datum = slot_getattr(violatorslot, fnum, &isnull);
2738 1646 : if (!isnull)
2739 : {
2740 : Oid foutoid;
2741 : bool typisvarlena;
2742 :
2743 1646 : getTypeOutputInfo(att->atttypid, &foutoid, &typisvarlena);
2744 1646 : val = OidOutputFunctionCall(foutoid, datum);
2745 : }
2746 : else
2747 0 : val = "null";
2748 :
2749 1646 : if (idx > 0)
2750 : {
2751 522 : appendStringInfoString(&key_names, ", ");
2752 522 : appendStringInfoString(&key_values, ", ");
2753 : }
2754 1646 : appendStringInfoString(&key_names, name);
2755 1646 : appendStringInfoString(&key_values, val);
2756 : }
2757 : }
2758 :
2759 1130 : if (partgone)
2760 34 : ereport(ERROR,
2761 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
2762 : errmsg("removing partition \"%s\" violates foreign key constraint \"%s\"",
2763 : RelationGetRelationName(pk_rel),
2764 : NameStr(riinfo->conname)),
2765 : errdetail("Key (%s)=(%s) is still referenced from table \"%s\".",
2766 : key_names.data, key_values.data,
2767 : RelationGetRelationName(fk_rel)),
2768 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
2769 1096 : else if (onfk)
2770 630 : ereport(ERROR,
2771 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
2772 : errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
2773 : RelationGetRelationName(fk_rel),
2774 : NameStr(riinfo->conname)),
2775 : has_perm ?
2776 : errdetail("Key (%s)=(%s) is not present in table \"%s\".",
2777 : key_names.data, key_values.data,
2778 : RelationGetRelationName(pk_rel)) :
2779 : errdetail("Key is not present in table \"%s\".",
2780 : RelationGetRelationName(pk_rel)),
2781 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
2782 466 : else if (is_restrict)
2783 30 : ereport(ERROR,
2784 : (errcode(ERRCODE_RESTRICT_VIOLATION),
2785 : errmsg("update or delete on table \"%s\" violates RESTRICT setting of foreign key constraint \"%s\" on table \"%s\"",
2786 : RelationGetRelationName(pk_rel),
2787 : NameStr(riinfo->conname),
2788 : RelationGetRelationName(fk_rel)),
2789 : has_perm ?
2790 : errdetail("Key (%s)=(%s) is referenced from table \"%s\".",
2791 : key_names.data, key_values.data,
2792 : RelationGetRelationName(fk_rel)) :
2793 : errdetail("Key is referenced from table \"%s\".",
2794 : RelationGetRelationName(fk_rel)),
2795 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
2796 : else
2797 436 : ereport(ERROR,
2798 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
2799 : errmsg("update or delete on table \"%s\" violates foreign key constraint \"%s\" on table \"%s\"",
2800 : RelationGetRelationName(pk_rel),
2801 : NameStr(riinfo->conname),
2802 : RelationGetRelationName(fk_rel)),
2803 : has_perm ?
2804 : errdetail("Key (%s)=(%s) is still referenced from table \"%s\".",
2805 : key_names.data, key_values.data,
2806 : RelationGetRelationName(fk_rel)) :
2807 : errdetail("Key is still referenced from table \"%s\".",
2808 : RelationGetRelationName(fk_rel)),
2809 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
2810 : }
2811 :
2812 :
2813 : /*
2814 : * ri_NullCheck -
2815 : *
2816 : * Determine the NULL state of all key values in a tuple
2817 : *
2818 : * Returns one of RI_KEYS_ALL_NULL, RI_KEYS_NONE_NULL or RI_KEYS_SOME_NULL.
2819 : */
2820 : static int
2821 7900 : ri_NullCheck(TupleDesc tupDesc,
2822 : TupleTableSlot *slot,
2823 : const RI_ConstraintInfo *riinfo, bool rel_is_pk)
2824 : {
2825 : const int16 *attnums;
2826 7900 : bool allnull = true;
2827 7900 : bool nonenull = true;
2828 :
2829 7900 : if (rel_is_pk)
2830 2332 : attnums = riinfo->pk_attnums;
2831 : else
2832 5568 : attnums = riinfo->fk_attnums;
2833 :
2834 18230 : for (int i = 0; i < riinfo->nkeys; i++)
2835 : {
2836 10330 : if (slot_attisnull(slot, attnums[i]))
2837 566 : nonenull = false;
2838 : else
2839 9764 : allnull = false;
2840 : }
2841 :
2842 7900 : if (allnull)
2843 282 : return RI_KEYS_ALL_NULL;
2844 :
2845 7618 : if (nonenull)
2846 7412 : return RI_KEYS_NONE_NULL;
2847 :
2848 206 : return RI_KEYS_SOME_NULL;
2849 : }
2850 :
2851 :
2852 : /*
2853 : * ri_InitHashTables -
2854 : *
2855 : * Initialize our internal hash tables.
2856 : */
2857 : static void
2858 426 : ri_InitHashTables(void)
2859 : {
2860 : HASHCTL ctl;
2861 :
2862 426 : ctl.keysize = sizeof(Oid);
2863 426 : ctl.entrysize = sizeof(RI_ConstraintInfo);
2864 426 : ri_constraint_cache = hash_create("RI constraint cache",
2865 : RI_INIT_CONSTRAINTHASHSIZE,
2866 : &ctl, HASH_ELEM | HASH_BLOBS);
2867 :
2868 : /* Arrange to flush cache on pg_constraint changes */
2869 426 : CacheRegisterSyscacheCallback(CONSTROID,
2870 : InvalidateConstraintCacheCallBack,
2871 : (Datum) 0);
2872 :
2873 426 : ctl.keysize = sizeof(RI_QueryKey);
2874 426 : ctl.entrysize = sizeof(RI_QueryHashEntry);
2875 426 : ri_query_cache = hash_create("RI query cache",
2876 : RI_INIT_QUERYHASHSIZE,
2877 : &ctl, HASH_ELEM | HASH_BLOBS);
2878 :
2879 426 : ctl.keysize = sizeof(RI_CompareKey);
2880 426 : ctl.entrysize = sizeof(RI_CompareHashEntry);
2881 426 : ri_compare_cache = hash_create("RI compare cache",
2882 : RI_INIT_QUERYHASHSIZE,
2883 : &ctl, HASH_ELEM | HASH_BLOBS);
2884 426 : }
2885 :
2886 :
2887 : /*
2888 : * ri_FetchPreparedPlan -
2889 : *
2890 : * Lookup for a query key in our private hash table of prepared
2891 : * and saved SPI execution plans. Return the plan if found or NULL.
2892 : */
2893 : static SPIPlanPtr
2894 6600 : ri_FetchPreparedPlan(RI_QueryKey *key)
2895 : {
2896 : RI_QueryHashEntry *entry;
2897 : SPIPlanPtr plan;
2898 :
2899 : /*
2900 : * On the first call initialize the hashtable
2901 : */
2902 6600 : if (!ri_query_cache)
2903 0 : ri_InitHashTables();
2904 :
2905 : /*
2906 : * Lookup for the key
2907 : */
2908 6600 : entry = (RI_QueryHashEntry *) hash_search(ri_query_cache,
2909 : key,
2910 : HASH_FIND, NULL);
2911 6600 : if (entry == NULL)
2912 2972 : return NULL;
2913 :
2914 : /*
2915 : * Check whether the plan is still valid. If it isn't, we don't want to
2916 : * simply rely on plancache.c to regenerate it; rather we should start
2917 : * from scratch and rebuild the query text too. This is to cover cases
2918 : * such as table/column renames. We depend on the plancache machinery to
2919 : * detect possible invalidations, though.
2920 : *
2921 : * CAUTION: this check is only trustworthy if the caller has already
2922 : * locked both FK and PK rels.
2923 : */
2924 3628 : plan = entry->plan;
2925 3628 : if (plan && SPI_plan_is_valid(plan))
2926 3242 : return plan;
2927 :
2928 : /*
2929 : * Otherwise we might as well flush the cached plan now, to free a little
2930 : * memory space before we make a new one.
2931 : */
2932 386 : entry->plan = NULL;
2933 386 : if (plan)
2934 386 : SPI_freeplan(plan);
2935 :
2936 386 : return NULL;
2937 : }
2938 :
2939 :
2940 : /*
2941 : * ri_HashPreparedPlan -
2942 : *
2943 : * Add another plan to our private SPI query plan hashtable.
2944 : */
2945 : static void
2946 3358 : ri_HashPreparedPlan(RI_QueryKey *key, SPIPlanPtr plan)
2947 : {
2948 : RI_QueryHashEntry *entry;
2949 : bool found;
2950 :
2951 : /*
2952 : * On the first call initialize the hashtable
2953 : */
2954 3358 : if (!ri_query_cache)
2955 0 : ri_InitHashTables();
2956 :
2957 : /*
2958 : * Add the new plan. We might be overwriting an entry previously found
2959 : * invalid by ri_FetchPreparedPlan.
2960 : */
2961 3358 : entry = (RI_QueryHashEntry *) hash_search(ri_query_cache,
2962 : key,
2963 : HASH_ENTER, &found);
2964 : Assert(!found || entry->plan == NULL);
2965 3358 : entry->plan = plan;
2966 3358 : }
2967 :
2968 :
2969 : /*
2970 : * ri_KeysEqual -
2971 : *
2972 : * Check if all key values in OLD and NEW are "equivalent":
2973 : * For normal FKs we check for equality.
2974 : * For temporal FKs we check that the PK side is a superset of its old value,
2975 : * or the FK side is a subset of its old value.
2976 : *
2977 : * Note: at some point we might wish to redefine this as checking for
2978 : * "IS NOT DISTINCT" rather than "=", that is, allow two nulls to be
2979 : * considered equal. Currently there is no need since all callers have
2980 : * previously found at least one of the rows to contain no nulls.
2981 : */
2982 : static bool
2983 2254 : ri_KeysEqual(Relation rel, TupleTableSlot *oldslot, TupleTableSlot *newslot,
2984 : const RI_ConstraintInfo *riinfo, bool rel_is_pk)
2985 : {
2986 : const int16 *attnums;
2987 :
2988 2254 : if (rel_is_pk)
2989 1454 : attnums = riinfo->pk_attnums;
2990 : else
2991 800 : attnums = riinfo->fk_attnums;
2992 :
2993 : /* XXX: could be worthwhile to fetch all necessary attrs at once */
2994 3572 : for (int i = 0; i < riinfo->nkeys; i++)
2995 : {
2996 : Datum oldvalue;
2997 : Datum newvalue;
2998 : bool isnull;
2999 :
3000 : /*
3001 : * Get one attribute's oldvalue. If it is NULL - they're not equal.
3002 : */
3003 2572 : oldvalue = slot_getattr(oldslot, attnums[i], &isnull);
3004 2572 : if (isnull)
3005 1254 : return false;
3006 :
3007 : /*
3008 : * Get one attribute's newvalue. If it is NULL - they're not equal.
3009 : */
3010 2542 : newvalue = slot_getattr(newslot, attnums[i], &isnull);
3011 2542 : if (isnull)
3012 0 : return false;
3013 :
3014 2542 : if (rel_is_pk)
3015 : {
3016 : /*
3017 : * If we are looking at the PK table, then do a bytewise
3018 : * comparison. We must propagate PK changes if the value is
3019 : * changed to one that "looks" different but would compare as
3020 : * equal using the equality operator. This only makes a
3021 : * difference for ON UPDATE CASCADE, but for consistency we treat
3022 : * all changes to the PK the same.
3023 : */
3024 1688 : CompactAttribute *att = TupleDescCompactAttr(oldslot->tts_tupleDescriptor, attnums[i] - 1);
3025 :
3026 1688 : if (!datum_image_eq(oldvalue, newvalue, att->attbyval, att->attlen))
3027 918 : return false;
3028 : }
3029 : else
3030 : {
3031 : Oid eq_opr;
3032 :
3033 : /*
3034 : * When comparing the PERIOD columns we can skip the check
3035 : * whenever the referencing column stayed equal or shrank, so test
3036 : * with the contained-by operator instead.
3037 : */
3038 854 : if (riinfo->hasperiod && i == riinfo->nkeys - 1)
3039 48 : eq_opr = riinfo->period_contained_by_oper;
3040 : else
3041 806 : eq_opr = riinfo->ff_eq_oprs[i];
3042 :
3043 : /*
3044 : * For the FK table, compare with the appropriate equality
3045 : * operator. Changes that compare equal will still satisfy the
3046 : * constraint after the update.
3047 : */
3048 854 : if (!ri_CompareWithCast(eq_opr, RIAttType(rel, attnums[i]), RIAttCollation(rel, attnums[i]),
3049 : newvalue, oldvalue))
3050 306 : return false;
3051 : }
3052 : }
3053 :
3054 1000 : return true;
3055 : }
3056 :
3057 :
3058 : /*
3059 : * ri_CompareWithCast -
3060 : *
3061 : * Call the appropriate comparison operator for two values.
3062 : * Normally this is equality, but for the PERIOD part of foreign keys
3063 : * it is ContainedBy, so the order of lhs vs rhs is significant.
3064 : * See below for how the collation is applied.
3065 : *
3066 : * NB: we have already checked that neither value is null.
3067 : */
3068 : static bool
3069 854 : ri_CompareWithCast(Oid eq_opr, Oid typeid, Oid collid,
3070 : Datum lhs, Datum rhs)
3071 : {
3072 854 : RI_CompareHashEntry *entry = ri_HashCompareOp(eq_opr, typeid);
3073 :
3074 : /* Do we need to cast the values? */
3075 854 : if (OidIsValid(entry->cast_func_finfo.fn_oid))
3076 : {
3077 12 : lhs = FunctionCall3(&entry->cast_func_finfo,
3078 : lhs,
3079 : Int32GetDatum(-1), /* typmod */
3080 : BoolGetDatum(false)); /* implicit coercion */
3081 12 : rhs = FunctionCall3(&entry->cast_func_finfo,
3082 : rhs,
3083 : Int32GetDatum(-1), /* typmod */
3084 : BoolGetDatum(false)); /* implicit coercion */
3085 : }
3086 :
3087 : /*
3088 : * Apply the comparison operator.
3089 : *
3090 : * Note: This function is part of a call stack that determines whether an
3091 : * update to a row is significant enough that it needs checking or action
3092 : * on the other side of a foreign-key constraint. Therefore, the
3093 : * comparison here would need to be done with the collation of the *other*
3094 : * table. For simplicity (e.g., we might not even have the other table
3095 : * open), we'll use our own collation. This is fine because we require
3096 : * that both collations have the same notion of equality (either they are
3097 : * both deterministic or else they are both the same).
3098 : *
3099 : * With range/multirangetypes, the collation of the base type is stored as
3100 : * part of the rangetype (pg_range.rngcollation), and always used, so
3101 : * there is no danger of inconsistency even using a non-equals operator.
3102 : * But if we support arbitrary types with PERIOD, we should perhaps just
3103 : * always force a re-check.
3104 : */
3105 854 : return DatumGetBool(FunctionCall2Coll(&entry->eq_opr_finfo, collid, lhs, rhs));
3106 : }
3107 :
3108 : /*
3109 : * ri_HashCompareOp -
3110 : *
3111 : * See if we know how to compare two values, and create a new hash entry
3112 : * if not.
3113 : */
3114 : static RI_CompareHashEntry *
3115 854 : ri_HashCompareOp(Oid eq_opr, Oid typeid)
3116 : {
3117 : RI_CompareKey key;
3118 : RI_CompareHashEntry *entry;
3119 : bool found;
3120 :
3121 : /*
3122 : * On the first call initialize the hashtable
3123 : */
3124 854 : if (!ri_compare_cache)
3125 0 : ri_InitHashTables();
3126 :
3127 : /*
3128 : * Find or create a hash entry. Note we're assuming RI_CompareKey
3129 : * contains no struct padding.
3130 : */
3131 854 : key.eq_opr = eq_opr;
3132 854 : key.typeid = typeid;
3133 854 : entry = (RI_CompareHashEntry *) hash_search(ri_compare_cache,
3134 : &key,
3135 : HASH_ENTER, &found);
3136 854 : if (!found)
3137 292 : entry->valid = false;
3138 :
3139 : /*
3140 : * If not already initialized, do so. Since we'll keep this hash entry
3141 : * for the life of the backend, put any subsidiary info for the function
3142 : * cache structs into TopMemoryContext.
3143 : */
3144 854 : if (!entry->valid)
3145 : {
3146 : Oid lefttype,
3147 : righttype,
3148 : castfunc;
3149 : CoercionPathType pathtype;
3150 :
3151 : /* We always need to know how to call the equality operator */
3152 292 : fmgr_info_cxt(get_opcode(eq_opr), &entry->eq_opr_finfo,
3153 : TopMemoryContext);
3154 :
3155 : /*
3156 : * If we chose to use a cast from FK to PK type, we may have to apply
3157 : * the cast function to get to the operator's input type.
3158 : *
3159 : * XXX eventually it would be good to support array-coercion cases
3160 : * here and in ri_CompareWithCast(). At the moment there is no point
3161 : * because cases involving nonidentical array types will be rejected
3162 : * at constraint creation time.
3163 : *
3164 : * XXX perhaps also consider supporting CoerceViaIO? No need at the
3165 : * moment since that will never be generated for implicit coercions.
3166 : */
3167 292 : op_input_types(eq_opr, &lefttype, &righttype);
3168 : Assert(lefttype == righttype);
3169 292 : if (typeid == lefttype)
3170 268 : castfunc = InvalidOid; /* simplest case */
3171 : else
3172 : {
3173 24 : pathtype = find_coercion_pathway(lefttype, typeid,
3174 : COERCION_IMPLICIT,
3175 : &castfunc);
3176 24 : if (pathtype != COERCION_PATH_FUNC &&
3177 : pathtype != COERCION_PATH_RELABELTYPE)
3178 : {
3179 : /*
3180 : * The declared input type of the eq_opr might be a
3181 : * polymorphic type such as ANYARRAY or ANYENUM, or other
3182 : * special cases such as RECORD; find_coercion_pathway
3183 : * currently doesn't subsume these special cases.
3184 : */
3185 18 : if (!IsBinaryCoercible(typeid, lefttype))
3186 0 : elog(ERROR, "no conversion function from %s to %s",
3187 : format_type_be(typeid),
3188 : format_type_be(lefttype));
3189 : }
3190 : }
3191 292 : if (OidIsValid(castfunc))
3192 6 : fmgr_info_cxt(castfunc, &entry->cast_func_finfo,
3193 : TopMemoryContext);
3194 : else
3195 286 : entry->cast_func_finfo.fn_oid = InvalidOid;
3196 292 : entry->valid = true;
3197 : }
3198 :
3199 854 : return entry;
3200 : }
3201 :
3202 :
3203 : /*
3204 : * Given a trigger function OID, determine whether it is an RI trigger,
3205 : * and if so whether it is attached to PK or FK relation.
3206 : */
3207 : int
3208 8786 : RI_FKey_trigger_type(Oid tgfoid)
3209 : {
3210 8786 : switch (tgfoid)
3211 : {
3212 3132 : case F_RI_FKEY_CASCADE_DEL:
3213 : case F_RI_FKEY_CASCADE_UPD:
3214 : case F_RI_FKEY_RESTRICT_DEL:
3215 : case F_RI_FKEY_RESTRICT_UPD:
3216 : case F_RI_FKEY_SETNULL_DEL:
3217 : case F_RI_FKEY_SETNULL_UPD:
3218 : case F_RI_FKEY_SETDEFAULT_DEL:
3219 : case F_RI_FKEY_SETDEFAULT_UPD:
3220 : case F_RI_FKEY_NOACTION_DEL:
3221 : case F_RI_FKEY_NOACTION_UPD:
3222 3132 : return RI_TRIGGER_PK;
3223 :
3224 2840 : case F_RI_FKEY_CHECK_INS:
3225 : case F_RI_FKEY_CHECK_UPD:
3226 2840 : return RI_TRIGGER_FK;
3227 : }
3228 :
3229 2814 : return RI_TRIGGER_NONE;
3230 : }
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