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 "catalog/pg_proc.h"
34 : #include "commands/trigger.h"
35 : #include "executor/executor.h"
36 : #include "executor/spi.h"
37 : #include "lib/ilist.h"
38 : #include "miscadmin.h"
39 : #include "parser/parse_coerce.h"
40 : #include "parser/parse_relation.h"
41 : #include "utils/acl.h"
42 : #include "utils/builtins.h"
43 : #include "utils/datum.h"
44 : #include "utils/fmgroids.h"
45 : #include "utils/guc.h"
46 : #include "utils/inval.h"
47 : #include "utils/lsyscache.h"
48 : #include "utils/memutils.h"
49 : #include "utils/rangetypes.h"
50 : #include "utils/rel.h"
51 : #include "utils/rls.h"
52 : #include "utils/ruleutils.h"
53 : #include "utils/snapmgr.h"
54 : #include "utils/syscache.h"
55 :
56 : /*
57 : * Local definitions
58 : */
59 :
60 : #define RI_MAX_NUMKEYS INDEX_MAX_KEYS
61 :
62 : #define RI_INIT_CONSTRAINTHASHSIZE 64
63 : #define RI_INIT_QUERYHASHSIZE (RI_INIT_CONSTRAINTHASHSIZE * 4)
64 :
65 : #define RI_KEYS_ALL_NULL 0
66 : #define RI_KEYS_SOME_NULL 1
67 : #define RI_KEYS_NONE_NULL 2
68 :
69 : /* RI query type codes */
70 : /* these queries are executed against the PK (referenced) table: */
71 : #define RI_PLAN_CHECK_LOOKUPPK 1
72 : #define RI_PLAN_CHECK_LOOKUPPK_FROM_PK 2
73 : #define RI_PLAN_LAST_ON_PK RI_PLAN_CHECK_LOOKUPPK_FROM_PK
74 : /* these queries are executed against the FK (referencing) table: */
75 : #define RI_PLAN_CASCADE_ONDELETE 3
76 : #define RI_PLAN_CASCADE_ONUPDATE 4
77 : #define RI_PLAN_NO_ACTION 5
78 : /* For RESTRICT, the same plan can be used for both ON DELETE and ON UPDATE triggers. */
79 : #define RI_PLAN_RESTRICT 6
80 : #define RI_PLAN_SETNULL_ONDELETE 7
81 : #define RI_PLAN_SETNULL_ONUPDATE 8
82 : #define RI_PLAN_SETDEFAULT_ONDELETE 9
83 : #define RI_PLAN_SETDEFAULT_ONUPDATE 10
84 :
85 : #define MAX_QUOTED_NAME_LEN (NAMEDATALEN*2+3)
86 : #define MAX_QUOTED_REL_NAME_LEN (MAX_QUOTED_NAME_LEN*2)
87 :
88 : #define RIAttName(rel, attnum) NameStr(*attnumAttName(rel, attnum))
89 : #define RIAttType(rel, attnum) attnumTypeId(rel, attnum)
90 : #define RIAttCollation(rel, attnum) attnumCollationId(rel, attnum)
91 :
92 : #define RI_TRIGTYPE_INSERT 1
93 : #define RI_TRIGTYPE_UPDATE 2
94 : #define RI_TRIGTYPE_DELETE 3
95 :
96 :
97 : /*
98 : * RI_ConstraintInfo
99 : *
100 : * Information extracted from an FK pg_constraint entry. This is cached in
101 : * ri_constraint_cache.
102 : *
103 : * Note that pf/pp/ff_eq_oprs may hold the overlaps operator instead of equals
104 : * for the PERIOD part of a temporal foreign key.
105 : */
106 : typedef struct RI_ConstraintInfo
107 : {
108 : Oid constraint_id; /* OID of pg_constraint entry (hash key) */
109 : bool valid; /* successfully initialized? */
110 : Oid constraint_root_id; /* OID of topmost ancestor constraint;
111 : * same as constraint_id if not inherited */
112 : uint32 oidHashValue; /* hash value of constraint_id */
113 : uint32 rootHashValue; /* hash value of constraint_root_id */
114 : NameData conname; /* name of the FK constraint */
115 : Oid pk_relid; /* referenced relation */
116 : Oid fk_relid; /* referencing relation */
117 : char confupdtype; /* foreign key's ON UPDATE action */
118 : char confdeltype; /* foreign key's ON DELETE action */
119 : int ndelsetcols; /* number of columns referenced in ON DELETE
120 : * SET clause */
121 : int16 confdelsetcols[RI_MAX_NUMKEYS]; /* attnums of cols to set on
122 : * delete */
123 : char confmatchtype; /* foreign key's match type */
124 : bool hasperiod; /* if the foreign key uses PERIOD */
125 : int nkeys; /* number of key columns */
126 : int16 pk_attnums[RI_MAX_NUMKEYS]; /* attnums of referenced cols */
127 : int16 fk_attnums[RI_MAX_NUMKEYS]; /* attnums of referencing cols */
128 : Oid pf_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (PK = FK) */
129 : Oid pp_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (PK = PK) */
130 : Oid ff_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (FK = FK) */
131 : Oid period_contained_by_oper; /* anyrange <@ anyrange */
132 : Oid agged_period_contained_by_oper; /* fkattr <@ range_agg(pkattr) */
133 : Oid period_intersect_oper; /* anyrange * anyrange */
134 : dlist_node valid_link; /* Link in list of valid entries */
135 : } RI_ConstraintInfo;
136 :
137 : /*
138 : * RI_QueryKey
139 : *
140 : * The key identifying a prepared SPI plan in our query hashtable
141 : */
142 : typedef struct RI_QueryKey
143 : {
144 : Oid constr_id; /* OID of pg_constraint entry */
145 : int32 constr_queryno; /* query type ID, see RI_PLAN_XXX above */
146 : } RI_QueryKey;
147 :
148 : /*
149 : * RI_QueryHashEntry
150 : */
151 : typedef struct RI_QueryHashEntry
152 : {
153 : RI_QueryKey key;
154 : SPIPlanPtr plan;
155 : } RI_QueryHashEntry;
156 :
157 : /*
158 : * RI_CompareKey
159 : *
160 : * The key identifying an entry showing how to compare two values
161 : */
162 : typedef struct RI_CompareKey
163 : {
164 : Oid eq_opr; /* the equality operator to apply */
165 : Oid typeid; /* the data type to apply it to */
166 : } RI_CompareKey;
167 :
168 : /*
169 : * RI_CompareHashEntry
170 : */
171 : typedef struct RI_CompareHashEntry
172 : {
173 : RI_CompareKey key;
174 : bool valid; /* successfully initialized? */
175 : FmgrInfo eq_opr_finfo; /* call info for equality fn */
176 : FmgrInfo cast_func_finfo; /* in case we must coerce input */
177 : } RI_CompareHashEntry;
178 :
179 :
180 : /*
181 : * Local data
182 : */
183 : static HTAB *ri_constraint_cache = NULL;
184 : static HTAB *ri_query_cache = NULL;
185 : static HTAB *ri_compare_cache = NULL;
186 : static dclist_head ri_constraint_cache_valid_list;
187 :
188 :
189 : /*
190 : * Local function prototypes
191 : */
192 : static bool ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
193 : TupleTableSlot *oldslot,
194 : const RI_ConstraintInfo *riinfo);
195 : static Datum ri_restrict(TriggerData *trigdata, bool is_no_action);
196 : static Datum ri_set(TriggerData *trigdata, bool is_set_null, int tgkind);
197 : static void quoteOneName(char *buffer, const char *name);
198 : static void quoteRelationName(char *buffer, Relation rel);
199 : static void ri_GenerateQual(StringInfo buf,
200 : const char *sep,
201 : const char *leftop, Oid leftoptype,
202 : Oid opoid,
203 : const char *rightop, Oid rightoptype);
204 : static void ri_GenerateQualCollation(StringInfo buf, Oid collation);
205 : static int ri_NullCheck(TupleDesc tupDesc, TupleTableSlot *slot,
206 : const RI_ConstraintInfo *riinfo, bool rel_is_pk);
207 : static void ri_BuildQueryKey(RI_QueryKey *key,
208 : const RI_ConstraintInfo *riinfo,
209 : int32 constr_queryno);
210 : static bool ri_KeysEqual(Relation rel, TupleTableSlot *oldslot, TupleTableSlot *newslot,
211 : const RI_ConstraintInfo *riinfo, bool rel_is_pk);
212 : static bool ri_CompareWithCast(Oid eq_opr, Oid typeid, Oid collid,
213 : Datum lhs, Datum rhs);
214 :
215 : static void ri_InitHashTables(void);
216 : static void InvalidateConstraintCacheCallBack(Datum arg, int cacheid, uint32 hashvalue);
217 : static SPIPlanPtr ri_FetchPreparedPlan(RI_QueryKey *key);
218 : static void ri_HashPreparedPlan(RI_QueryKey *key, SPIPlanPtr plan);
219 : static RI_CompareHashEntry *ri_HashCompareOp(Oid eq_opr, Oid typeid);
220 :
221 : static void ri_CheckTrigger(FunctionCallInfo fcinfo, const char *funcname,
222 : int tgkind);
223 : static const RI_ConstraintInfo *ri_FetchConstraintInfo(Trigger *trigger,
224 : Relation trig_rel, bool rel_is_pk);
225 : static const RI_ConstraintInfo *ri_LoadConstraintInfo(Oid constraintOid);
226 : static Oid get_ri_constraint_root(Oid constrOid);
227 : static SPIPlanPtr ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
228 : RI_QueryKey *qkey, Relation fk_rel, Relation pk_rel);
229 : static bool ri_PerformCheck(const RI_ConstraintInfo *riinfo,
230 : RI_QueryKey *qkey, SPIPlanPtr qplan,
231 : Relation fk_rel, Relation pk_rel,
232 : TupleTableSlot *oldslot, TupleTableSlot *newslot,
233 : bool is_restrict,
234 : bool detectNewRows, int expect_OK);
235 : static void ri_ExtractValues(Relation rel, TupleTableSlot *slot,
236 : const RI_ConstraintInfo *riinfo, bool rel_is_pk,
237 : Datum *vals, char *nulls);
238 : static void ri_ReportViolation(const RI_ConstraintInfo *riinfo,
239 : Relation pk_rel, Relation fk_rel,
240 : TupleTableSlot *violatorslot, TupleDesc tupdesc,
241 : int queryno, bool is_restrict, bool partgone) pg_attribute_noreturn();
242 :
243 :
244 : /*
245 : * RI_FKey_check -
246 : *
247 : * Check foreign key existence (combined for INSERT and UPDATE).
248 : */
249 : static Datum
250 4534 : RI_FKey_check(TriggerData *trigdata)
251 : {
252 : const RI_ConstraintInfo *riinfo;
253 : Relation fk_rel;
254 : Relation pk_rel;
255 : TupleTableSlot *newslot;
256 : RI_QueryKey qkey;
257 : SPIPlanPtr qplan;
258 :
259 4534 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
260 : trigdata->tg_relation, false);
261 :
262 4534 : if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
263 448 : newslot = trigdata->tg_newslot;
264 : else
265 4086 : newslot = trigdata->tg_trigslot;
266 :
267 : /*
268 : * We should not even consider checking the row if it is no longer valid,
269 : * since it was either deleted (so the deferred check should be skipped)
270 : * or updated (in which case only the latest version of the row should be
271 : * checked). Test its liveness according to SnapshotSelf. We need pin
272 : * and lock on the buffer to call HeapTupleSatisfiesVisibility. Caller
273 : * should be holding pin, but not lock.
274 : */
275 4534 : if (!table_tuple_satisfies_snapshot(trigdata->tg_relation, newslot, SnapshotSelf))
276 60 : return PointerGetDatum(NULL);
277 :
278 : /*
279 : * Get the relation descriptors of the FK and PK tables.
280 : *
281 : * pk_rel is opened in RowShareLock mode since that's what our eventual
282 : * SELECT FOR KEY SHARE will get on it.
283 : */
284 4474 : fk_rel = trigdata->tg_relation;
285 4474 : pk_rel = table_open(riinfo->pk_relid, RowShareLock);
286 :
287 4474 : switch (ri_NullCheck(RelationGetDescr(fk_rel), newslot, riinfo, false))
288 : {
289 132 : case RI_KEYS_ALL_NULL:
290 :
291 : /*
292 : * No further check needed - an all-NULL key passes every type of
293 : * foreign key constraint.
294 : */
295 132 : table_close(pk_rel, RowShareLock);
296 132 : return PointerGetDatum(NULL);
297 :
298 156 : case RI_KEYS_SOME_NULL:
299 :
300 : /*
301 : * This is the only case that differs between the three kinds of
302 : * MATCH.
303 : */
304 156 : switch (riinfo->confmatchtype)
305 : {
306 36 : case FKCONSTR_MATCH_FULL:
307 :
308 : /*
309 : * Not allowed - MATCH FULL says either all or none of the
310 : * attributes can be NULLs
311 : */
312 36 : ereport(ERROR,
313 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
314 : errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
315 : RelationGetRelationName(fk_rel),
316 : NameStr(riinfo->conname)),
317 : errdetail("MATCH FULL does not allow mixing of null and nonnull key values."),
318 : errtableconstraint(fk_rel,
319 : NameStr(riinfo->conname))));
320 : table_close(pk_rel, RowShareLock);
321 : return PointerGetDatum(NULL);
322 :
323 120 : case FKCONSTR_MATCH_SIMPLE:
324 :
325 : /*
326 : * MATCH SIMPLE - if ANY column is null, the key passes
327 : * the constraint.
328 : */
329 120 : table_close(pk_rel, RowShareLock);
330 120 : return PointerGetDatum(NULL);
331 :
332 : #ifdef NOT_USED
333 : case FKCONSTR_MATCH_PARTIAL:
334 :
335 : /*
336 : * MATCH PARTIAL - all non-null columns must match. (not
337 : * implemented, can be done by modifying the query below
338 : * to only include non-null columns, or by writing a
339 : * special version here)
340 : */
341 : break;
342 : #endif
343 : }
344 :
345 : case RI_KEYS_NONE_NULL:
346 :
347 : /*
348 : * Have a full qualified key - continue below for all three kinds
349 : * of MATCH.
350 : */
351 4186 : break;
352 : }
353 :
354 4186 : SPI_connect();
355 :
356 : /* Fetch or prepare a saved plan for the real check */
357 4186 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CHECK_LOOKUPPK);
358 :
359 4186 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
360 : {
361 : StringInfoData querybuf;
362 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
363 : char attname[MAX_QUOTED_NAME_LEN];
364 : char paramname[16];
365 : const char *querysep;
366 : Oid queryoids[RI_MAX_NUMKEYS];
367 : const char *pk_only;
368 :
369 : /* ----------
370 : * The query string built is
371 : * SELECT 1 FROM [ONLY] <pktable> x WHERE pkatt1 = $1 [AND ...]
372 : * FOR KEY SHARE OF x
373 : * The type id's for the $ parameters are those of the
374 : * corresponding FK attributes.
375 : *
376 : * But for temporal FKs we need to make sure
377 : * the FK's range is completely covered.
378 : * So we use this query instead:
379 : * SELECT 1
380 : * FROM (
381 : * SELECT pkperiodatt AS r
382 : * FROM [ONLY] pktable x
383 : * WHERE pkatt1 = $1 [AND ...]
384 : * AND pkperiodatt && $n
385 : * FOR KEY SHARE OF x
386 : * ) x1
387 : * HAVING $n <@ range_agg(x1.r)
388 : * Note if FOR KEY SHARE ever allows GROUP BY and HAVING
389 : * we can make this a bit simpler.
390 : * ----------
391 : */
392 2170 : initStringInfo(&querybuf);
393 4340 : pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
394 2170 : "" : "ONLY ";
395 2170 : quoteRelationName(pkrelname, pk_rel);
396 2170 : if (riinfo->hasperiod)
397 : {
398 128 : quoteOneName(attname,
399 128 : RIAttName(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]));
400 :
401 128 : appendStringInfo(&querybuf,
402 : "SELECT 1 FROM (SELECT %s AS r FROM %s%s x",
403 : attname, pk_only, pkrelname);
404 : }
405 : else
406 : {
407 2042 : appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
408 : pk_only, pkrelname);
409 : }
410 2170 : querysep = "WHERE";
411 4708 : for (int i = 0; i < riinfo->nkeys; i++)
412 : {
413 2538 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
414 2538 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
415 :
416 2538 : quoteOneName(attname,
417 2538 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
418 2538 : sprintf(paramname, "$%d", i + 1);
419 2538 : ri_GenerateQual(&querybuf, querysep,
420 : attname, pk_type,
421 : riinfo->pf_eq_oprs[i],
422 : paramname, fk_type);
423 2538 : querysep = "AND";
424 2538 : queryoids[i] = fk_type;
425 : }
426 2170 : appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
427 2170 : if (riinfo->hasperiod)
428 : {
429 128 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]);
430 :
431 128 : appendStringInfo(&querybuf, ") x1 HAVING ");
432 128 : sprintf(paramname, "$%d", riinfo->nkeys);
433 128 : ri_GenerateQual(&querybuf, "",
434 : paramname, fk_type,
435 : riinfo->agged_period_contained_by_oper,
436 : "pg_catalog.range_agg", ANYMULTIRANGEOID);
437 128 : appendStringInfo(&querybuf, "(x1.r)");
438 : }
439 :
440 : /* Prepare and save the plan */
441 2170 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
442 : &qkey, fk_rel, pk_rel);
443 : }
444 :
445 : /*
446 : * Now check that foreign key exists in PK table
447 : *
448 : * XXX detectNewRows must be true when a partitioned table is on the
449 : * referenced side. The reason is that our snapshot must be fresh in
450 : * order for the hack in find_inheritance_children() to work.
451 : */
452 4186 : ri_PerformCheck(riinfo, &qkey, qplan,
453 : fk_rel, pk_rel,
454 : NULL, newslot,
455 : false,
456 4186 : pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE,
457 : SPI_OK_SELECT);
458 :
459 3632 : if (SPI_finish() != SPI_OK_FINISH)
460 0 : elog(ERROR, "SPI_finish failed");
461 :
462 3632 : table_close(pk_rel, RowShareLock);
463 :
464 3632 : return PointerGetDatum(NULL);
465 : }
466 :
467 :
468 : /*
469 : * RI_FKey_check_ins -
470 : *
471 : * Check foreign key existence at insert event on FK table.
472 : */
473 : Datum
474 4086 : RI_FKey_check_ins(PG_FUNCTION_ARGS)
475 : {
476 : /* Check that this is a valid trigger call on the right time and event. */
477 4086 : ri_CheckTrigger(fcinfo, "RI_FKey_check_ins", RI_TRIGTYPE_INSERT);
478 :
479 : /* Share code with UPDATE case. */
480 4086 : return RI_FKey_check((TriggerData *) fcinfo->context);
481 : }
482 :
483 :
484 : /*
485 : * RI_FKey_check_upd -
486 : *
487 : * Check foreign key existence at update event on FK table.
488 : */
489 : Datum
490 448 : RI_FKey_check_upd(PG_FUNCTION_ARGS)
491 : {
492 : /* Check that this is a valid trigger call on the right time and event. */
493 448 : ri_CheckTrigger(fcinfo, "RI_FKey_check_upd", RI_TRIGTYPE_UPDATE);
494 :
495 : /* Share code with INSERT case. */
496 448 : return RI_FKey_check((TriggerData *) fcinfo->context);
497 : }
498 :
499 :
500 : /*
501 : * ri_Check_Pk_Match
502 : *
503 : * Check to see if another PK row has been created that provides the same
504 : * key values as the "oldslot" that's been modified or deleted in our trigger
505 : * event. Returns true if a match is found in the PK table.
506 : *
507 : * We assume the caller checked that the oldslot contains no NULL key values,
508 : * since otherwise a match is impossible.
509 : */
510 : static bool
511 762 : ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
512 : TupleTableSlot *oldslot,
513 : const RI_ConstraintInfo *riinfo)
514 : {
515 : SPIPlanPtr qplan;
516 : RI_QueryKey qkey;
517 : bool result;
518 :
519 : /* Only called for non-null rows */
520 : Assert(ri_NullCheck(RelationGetDescr(pk_rel), oldslot, riinfo, true) == RI_KEYS_NONE_NULL);
521 :
522 762 : SPI_connect();
523 :
524 : /*
525 : * Fetch or prepare a saved plan for checking PK table with values coming
526 : * from a PK row
527 : */
528 762 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CHECK_LOOKUPPK_FROM_PK);
529 :
530 762 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
531 : {
532 : StringInfoData querybuf;
533 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
534 : char attname[MAX_QUOTED_NAME_LEN];
535 : char paramname[16];
536 : const char *querysep;
537 : const char *pk_only;
538 : Oid queryoids[RI_MAX_NUMKEYS];
539 :
540 : /* ----------
541 : * The query string built is
542 : * SELECT 1 FROM [ONLY] <pktable> x WHERE pkatt1 = $1 [AND ...]
543 : * FOR KEY SHARE OF x
544 : * The type id's for the $ parameters are those of the
545 : * PK attributes themselves.
546 : *
547 : * But for temporal FKs we need to make sure
548 : * the old PK's range is completely covered.
549 : * So we use this query instead:
550 : * SELECT 1
551 : * FROM (
552 : * SELECT pkperiodatt AS r
553 : * FROM [ONLY] pktable x
554 : * WHERE pkatt1 = $1 [AND ...]
555 : * AND pkperiodatt && $n
556 : * FOR KEY SHARE OF x
557 : * ) x1
558 : * HAVING $n <@ range_agg(x1.r)
559 : * Note if FOR KEY SHARE ever allows GROUP BY and HAVING
560 : * we can make this a bit simpler.
561 : * ----------
562 : */
563 344 : initStringInfo(&querybuf);
564 688 : pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
565 344 : "" : "ONLY ";
566 344 : quoteRelationName(pkrelname, pk_rel);
567 344 : if (riinfo->hasperiod)
568 : {
569 0 : quoteOneName(attname, RIAttName(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]));
570 :
571 0 : appendStringInfo(&querybuf,
572 : "SELECT 1 FROM (SELECT %s AS r FROM %s%s x",
573 : attname, pk_only, pkrelname);
574 : }
575 : else
576 : {
577 344 : appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
578 : pk_only, pkrelname);
579 : }
580 344 : querysep = "WHERE";
581 812 : for (int i = 0; i < riinfo->nkeys; i++)
582 : {
583 468 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
584 :
585 468 : quoteOneName(attname,
586 468 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
587 468 : sprintf(paramname, "$%d", i + 1);
588 468 : ri_GenerateQual(&querybuf, querysep,
589 : attname, pk_type,
590 : riinfo->pp_eq_oprs[i],
591 : paramname, pk_type);
592 468 : querysep = "AND";
593 468 : queryoids[i] = pk_type;
594 : }
595 344 : appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
596 344 : if (riinfo->hasperiod)
597 : {
598 0 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]);
599 :
600 0 : appendStringInfo(&querybuf, ") x1 HAVING ");
601 0 : sprintf(paramname, "$%d", riinfo->nkeys);
602 0 : ri_GenerateQual(&querybuf, "",
603 : paramname, fk_type,
604 : riinfo->agged_period_contained_by_oper,
605 : "pg_catalog.range_agg", ANYMULTIRANGEOID);
606 0 : appendStringInfo(&querybuf, "(x1.r)");
607 : }
608 :
609 : /* Prepare and save the plan */
610 344 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
611 : &qkey, fk_rel, pk_rel);
612 : }
613 :
614 : /*
615 : * We have a plan now. Run it.
616 : */
617 762 : result = ri_PerformCheck(riinfo, &qkey, qplan,
618 : fk_rel, pk_rel,
619 : oldslot, NULL,
620 : false,
621 : true, /* treat like update */
622 : SPI_OK_SELECT);
623 :
624 762 : if (SPI_finish() != SPI_OK_FINISH)
625 0 : elog(ERROR, "SPI_finish failed");
626 :
627 762 : return result;
628 : }
629 :
630 :
631 : /*
632 : * RI_FKey_noaction_del -
633 : *
634 : * Give an error and roll back the current transaction if the
635 : * delete has resulted in a violation of the given referential
636 : * integrity constraint.
637 : */
638 : Datum
639 438 : RI_FKey_noaction_del(PG_FUNCTION_ARGS)
640 : {
641 : /* Check that this is a valid trigger call on the right time and event. */
642 438 : ri_CheckTrigger(fcinfo, "RI_FKey_noaction_del", RI_TRIGTYPE_DELETE);
643 :
644 : /* Share code with RESTRICT/UPDATE cases. */
645 438 : return ri_restrict((TriggerData *) fcinfo->context, true);
646 : }
647 :
648 : /*
649 : * RI_FKey_restrict_del -
650 : *
651 : * Restrict delete from PK table to rows unreferenced by foreign key.
652 : *
653 : * The SQL standard intends that this referential action occur exactly when
654 : * the delete is performed, rather than after. This appears to be
655 : * the only difference between "NO ACTION" and "RESTRICT". In Postgres
656 : * we still implement this as an AFTER trigger, but it's non-deferrable.
657 : */
658 : Datum
659 78 : RI_FKey_restrict_del(PG_FUNCTION_ARGS)
660 : {
661 : /* Check that this is a valid trigger call on the right time and event. */
662 78 : ri_CheckTrigger(fcinfo, "RI_FKey_restrict_del", RI_TRIGTYPE_DELETE);
663 :
664 : /* Share code with NO ACTION/UPDATE cases. */
665 78 : return ri_restrict((TriggerData *) fcinfo->context, false);
666 : }
667 :
668 : /*
669 : * RI_FKey_noaction_upd -
670 : *
671 : * Give an error and roll back the current transaction if the
672 : * update has resulted in a violation of the given referential
673 : * integrity constraint.
674 : */
675 : Datum
676 528 : RI_FKey_noaction_upd(PG_FUNCTION_ARGS)
677 : {
678 : /* Check that this is a valid trigger call on the right time and event. */
679 528 : ri_CheckTrigger(fcinfo, "RI_FKey_noaction_upd", RI_TRIGTYPE_UPDATE);
680 :
681 : /* Share code with RESTRICT/DELETE cases. */
682 528 : return ri_restrict((TriggerData *) fcinfo->context, true);
683 : }
684 :
685 : /*
686 : * RI_FKey_restrict_upd -
687 : *
688 : * Restrict update of PK to rows unreferenced by foreign key.
689 : *
690 : * The SQL standard intends that this referential action occur exactly when
691 : * the update is performed, rather than after. This appears to be
692 : * the only difference between "NO ACTION" and "RESTRICT". In Postgres
693 : * we still implement this as an AFTER trigger, but it's non-deferrable.
694 : */
695 : Datum
696 96 : RI_FKey_restrict_upd(PG_FUNCTION_ARGS)
697 : {
698 : /* Check that this is a valid trigger call on the right time and event. */
699 96 : ri_CheckTrigger(fcinfo, "RI_FKey_restrict_upd", RI_TRIGTYPE_UPDATE);
700 :
701 : /* Share code with NO ACTION/DELETE cases. */
702 96 : return ri_restrict((TriggerData *) fcinfo->context, false);
703 : }
704 :
705 : /*
706 : * ri_restrict -
707 : *
708 : * Common code for ON DELETE RESTRICT, ON DELETE NO ACTION,
709 : * ON UPDATE RESTRICT, and ON UPDATE NO ACTION.
710 : */
711 : static Datum
712 1272 : ri_restrict(TriggerData *trigdata, bool is_no_action)
713 : {
714 : const RI_ConstraintInfo *riinfo;
715 : Relation fk_rel;
716 : Relation pk_rel;
717 : TupleTableSlot *oldslot;
718 : RI_QueryKey qkey;
719 : SPIPlanPtr qplan;
720 :
721 1272 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
722 : trigdata->tg_relation, true);
723 :
724 : /*
725 : * Get the relation descriptors of the FK and PK tables and the old tuple.
726 : *
727 : * fk_rel is opened in RowShareLock mode since that's what our eventual
728 : * SELECT FOR KEY SHARE will get on it.
729 : */
730 1272 : fk_rel = table_open(riinfo->fk_relid, RowShareLock);
731 1272 : pk_rel = trigdata->tg_relation;
732 1272 : oldslot = trigdata->tg_trigslot;
733 :
734 : /*
735 : * If another PK row now exists providing the old key values, we should
736 : * not do anything. However, this check should only be made in the NO
737 : * ACTION case; in RESTRICT cases we don't wish to allow another row to be
738 : * substituted.
739 : *
740 : * If the foreign key has PERIOD, we incorporate looking for replacement
741 : * rows in the main SQL query below, so we needn't do it here.
742 : */
743 2034 : if (is_no_action && !riinfo->hasperiod &&
744 762 : ri_Check_Pk_Match(pk_rel, fk_rel, oldslot, riinfo))
745 : {
746 58 : table_close(fk_rel, RowShareLock);
747 58 : return PointerGetDatum(NULL);
748 : }
749 :
750 1214 : SPI_connect();
751 :
752 : /*
753 : * Fetch or prepare a saved plan for the restrict lookup (it's the same
754 : * query for delete and update cases)
755 : */
756 1214 : ri_BuildQueryKey(&qkey, riinfo, is_no_action ? RI_PLAN_NO_ACTION : RI_PLAN_RESTRICT);
757 :
758 1214 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
759 : {
760 : StringInfoData querybuf;
761 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
762 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
763 : char attname[MAX_QUOTED_NAME_LEN];
764 : char periodattname[MAX_QUOTED_NAME_LEN];
765 : char paramname[16];
766 : const char *querysep;
767 : Oid queryoids[RI_MAX_NUMKEYS];
768 : const char *fk_only;
769 :
770 : /* ----------
771 : * The query string built is
772 : * SELECT 1 FROM [ONLY] <fktable> x WHERE $1 = fkatt1 [AND ...]
773 : * FOR KEY SHARE OF x
774 : * The type id's for the $ parameters are those of the
775 : * corresponding PK attributes.
776 : * ----------
777 : */
778 508 : initStringInfo(&querybuf);
779 1016 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
780 508 : "" : "ONLY ";
781 508 : quoteRelationName(fkrelname, fk_rel);
782 508 : appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
783 : fk_only, fkrelname);
784 508 : querysep = "WHERE";
785 1342 : for (int i = 0; i < riinfo->nkeys; i++)
786 : {
787 834 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
788 834 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
789 :
790 834 : quoteOneName(attname,
791 834 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
792 834 : sprintf(paramname, "$%d", i + 1);
793 834 : ri_GenerateQual(&querybuf, querysep,
794 : paramname, pk_type,
795 : riinfo->pf_eq_oprs[i],
796 : attname, fk_type);
797 834 : querysep = "AND";
798 834 : queryoids[i] = pk_type;
799 : }
800 :
801 : /*----------
802 : * For temporal foreign keys, a reference could still be valid if the
803 : * referenced range didn't change too much. Also if a referencing
804 : * range extends past the current PK row, we don't want to check that
805 : * part: some other PK row should fulfill it. We only want to check
806 : * the part matching the PK record we've changed. Therefore to find
807 : * invalid records we do this:
808 : *
809 : * SELECT 1 FROM [ONLY] <fktable> x WHERE $1 = x.fkatt1 [AND ...]
810 : * -- begin temporal
811 : * AND $n && x.fkperiod
812 : * AND NOT coalesce((x.fkperiod * $n) <@
813 : * (SELECT range_agg(r)
814 : * FROM (SELECT y.pkperiod r
815 : * FROM [ONLY] <pktable> y
816 : * WHERE $1 = y.pkatt1 [AND ...] AND $n && y.pkperiod
817 : * FOR KEY SHARE OF y) y2), false)
818 : * -- end temporal
819 : * FOR KEY SHARE OF x
820 : *
821 : * We need the coalesce in case the first subquery returns no rows.
822 : * We need the second subquery because FOR KEY SHARE doesn't support
823 : * aggregate queries.
824 : */
825 508 : if (riinfo->hasperiod && is_no_action)
826 : {
827 128 : Oid pk_period_type = RIAttType(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]);
828 128 : Oid fk_period_type = RIAttType(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]);
829 : StringInfoData intersectbuf;
830 : StringInfoData replacementsbuf;
831 256 : char *pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
832 128 : "" : "ONLY ";
833 :
834 128 : quoteOneName(attname, RIAttName(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]));
835 128 : sprintf(paramname, "$%d", riinfo->nkeys);
836 :
837 128 : appendStringInfoString(&querybuf, " AND NOT coalesce(");
838 :
839 : /* Intersect the fk with the old pk range */
840 128 : initStringInfo(&intersectbuf);
841 128 : appendStringInfoString(&intersectbuf, "(");
842 128 : ri_GenerateQual(&intersectbuf, "",
843 : attname, fk_period_type,
844 : riinfo->period_intersect_oper,
845 : paramname, pk_period_type);
846 128 : appendStringInfoString(&intersectbuf, ")");
847 :
848 : /* Find the remaining history */
849 128 : initStringInfo(&replacementsbuf);
850 128 : appendStringInfoString(&replacementsbuf, "(SELECT pg_catalog.range_agg(r) FROM ");
851 :
852 128 : quoteOneName(periodattname, RIAttName(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]));
853 128 : quoteRelationName(pkrelname, pk_rel);
854 128 : appendStringInfo(&replacementsbuf, "(SELECT y.%s r FROM %s%s y",
855 : periodattname, pk_only, pkrelname);
856 :
857 : /* Restrict pk rows to what matches */
858 128 : querysep = "WHERE";
859 384 : for (int i = 0; i < riinfo->nkeys; i++)
860 : {
861 256 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
862 :
863 256 : quoteOneName(attname,
864 256 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
865 256 : sprintf(paramname, "$%d", i + 1);
866 256 : ri_GenerateQual(&replacementsbuf, querysep,
867 : paramname, pk_type,
868 : riinfo->pp_eq_oprs[i],
869 : attname, pk_type);
870 256 : querysep = "AND";
871 256 : queryoids[i] = pk_type;
872 : }
873 128 : appendStringInfoString(&replacementsbuf, " FOR KEY SHARE OF y) y2)");
874 :
875 128 : ri_GenerateQual(&querybuf, "",
876 128 : intersectbuf.data, fk_period_type,
877 : riinfo->agged_period_contained_by_oper,
878 128 : replacementsbuf.data, ANYMULTIRANGEOID);
879 : /* end of coalesce: */
880 128 : appendStringInfoString(&querybuf, ", false)");
881 : }
882 :
883 508 : appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
884 :
885 : /* Prepare and save the plan */
886 508 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
887 : &qkey, fk_rel, pk_rel);
888 : }
889 :
890 : /*
891 : * We have a plan now. Run it to check for existing references.
892 : */
893 1214 : ri_PerformCheck(riinfo, &qkey, qplan,
894 : fk_rel, pk_rel,
895 : oldslot, NULL,
896 1214 : !is_no_action,
897 : true, /* must detect new rows */
898 1214 : SPI_OK_SELECT);
899 :
900 694 : if (SPI_finish() != SPI_OK_FINISH)
901 0 : elog(ERROR, "SPI_finish failed");
902 :
903 694 : table_close(fk_rel, RowShareLock);
904 :
905 694 : return PointerGetDatum(NULL);
906 : }
907 :
908 :
909 : /*
910 : * RI_FKey_cascade_del -
911 : *
912 : * Cascaded delete foreign key references at delete event on PK table.
913 : */
914 : Datum
915 148 : RI_FKey_cascade_del(PG_FUNCTION_ARGS)
916 : {
917 148 : TriggerData *trigdata = (TriggerData *) fcinfo->context;
918 : const RI_ConstraintInfo *riinfo;
919 : Relation fk_rel;
920 : Relation pk_rel;
921 : TupleTableSlot *oldslot;
922 : RI_QueryKey qkey;
923 : SPIPlanPtr qplan;
924 :
925 : /* Check that this is a valid trigger call on the right time and event. */
926 148 : ri_CheckTrigger(fcinfo, "RI_FKey_cascade_del", RI_TRIGTYPE_DELETE);
927 :
928 148 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
929 : trigdata->tg_relation, true);
930 :
931 : /*
932 : * Get the relation descriptors of the FK and PK tables and the old tuple.
933 : *
934 : * fk_rel is opened in RowExclusiveLock mode since that's what our
935 : * eventual DELETE will get on it.
936 : */
937 148 : fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
938 148 : pk_rel = trigdata->tg_relation;
939 148 : oldslot = trigdata->tg_trigslot;
940 :
941 148 : SPI_connect();
942 :
943 : /* Fetch or prepare a saved plan for the cascaded delete */
944 148 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CASCADE_ONDELETE);
945 :
946 148 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
947 : {
948 : StringInfoData querybuf;
949 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
950 : char attname[MAX_QUOTED_NAME_LEN];
951 : char paramname[16];
952 : const char *querysep;
953 : Oid queryoids[RI_MAX_NUMKEYS];
954 : const char *fk_only;
955 :
956 : /* ----------
957 : * The query string built is
958 : * DELETE FROM [ONLY] <fktable> WHERE $1 = fkatt1 [AND ...]
959 : * The type id's for the $ parameters are those of the
960 : * corresponding PK attributes.
961 : * ----------
962 : */
963 90 : initStringInfo(&querybuf);
964 180 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
965 90 : "" : "ONLY ";
966 90 : quoteRelationName(fkrelname, fk_rel);
967 90 : appendStringInfo(&querybuf, "DELETE FROM %s%s",
968 : fk_only, fkrelname);
969 90 : querysep = "WHERE";
970 202 : for (int i = 0; i < riinfo->nkeys; i++)
971 : {
972 112 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
973 112 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
974 :
975 112 : quoteOneName(attname,
976 112 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
977 112 : sprintf(paramname, "$%d", i + 1);
978 112 : ri_GenerateQual(&querybuf, querysep,
979 : paramname, pk_type,
980 : riinfo->pf_eq_oprs[i],
981 : attname, fk_type);
982 112 : querysep = "AND";
983 112 : queryoids[i] = pk_type;
984 : }
985 :
986 : /* Prepare and save the plan */
987 90 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
988 : &qkey, fk_rel, pk_rel);
989 : }
990 :
991 : /*
992 : * We have a plan now. Build up the arguments from the key values in the
993 : * deleted PK tuple and delete the referencing rows
994 : */
995 148 : ri_PerformCheck(riinfo, &qkey, qplan,
996 : fk_rel, pk_rel,
997 : oldslot, NULL,
998 : false,
999 : true, /* must detect new rows */
1000 : SPI_OK_DELETE);
1001 :
1002 146 : if (SPI_finish() != SPI_OK_FINISH)
1003 0 : elog(ERROR, "SPI_finish failed");
1004 :
1005 146 : table_close(fk_rel, RowExclusiveLock);
1006 :
1007 146 : return PointerGetDatum(NULL);
1008 : }
1009 :
1010 :
1011 : /*
1012 : * RI_FKey_cascade_upd -
1013 : *
1014 : * Cascaded update foreign key references at update event on PK table.
1015 : */
1016 : Datum
1017 204 : RI_FKey_cascade_upd(PG_FUNCTION_ARGS)
1018 : {
1019 204 : TriggerData *trigdata = (TriggerData *) fcinfo->context;
1020 : const RI_ConstraintInfo *riinfo;
1021 : Relation fk_rel;
1022 : Relation pk_rel;
1023 : TupleTableSlot *newslot;
1024 : TupleTableSlot *oldslot;
1025 : RI_QueryKey qkey;
1026 : SPIPlanPtr qplan;
1027 :
1028 : /* Check that this is a valid trigger call on the right time and event. */
1029 204 : ri_CheckTrigger(fcinfo, "RI_FKey_cascade_upd", RI_TRIGTYPE_UPDATE);
1030 :
1031 204 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
1032 : trigdata->tg_relation, true);
1033 :
1034 : /*
1035 : * Get the relation descriptors of the FK and PK tables and the new and
1036 : * old tuple.
1037 : *
1038 : * fk_rel is opened in RowExclusiveLock mode since that's what our
1039 : * eventual UPDATE will get on it.
1040 : */
1041 204 : fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
1042 204 : pk_rel = trigdata->tg_relation;
1043 204 : newslot = trigdata->tg_newslot;
1044 204 : oldslot = trigdata->tg_trigslot;
1045 :
1046 204 : SPI_connect();
1047 :
1048 : /* Fetch or prepare a saved plan for the cascaded update */
1049 204 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CASCADE_ONUPDATE);
1050 :
1051 204 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
1052 : {
1053 : StringInfoData querybuf;
1054 : StringInfoData qualbuf;
1055 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1056 : char attname[MAX_QUOTED_NAME_LEN];
1057 : char paramname[16];
1058 : const char *querysep;
1059 : const char *qualsep;
1060 : Oid queryoids[RI_MAX_NUMKEYS * 2];
1061 : const char *fk_only;
1062 :
1063 : /* ----------
1064 : * The query string built is
1065 : * UPDATE [ONLY] <fktable> SET fkatt1 = $1 [, ...]
1066 : * WHERE $n = fkatt1 [AND ...]
1067 : * The type id's for the $ parameters are those of the
1068 : * corresponding PK attributes. Note that we are assuming
1069 : * there is an assignment cast from the PK to the FK type;
1070 : * else the parser will fail.
1071 : * ----------
1072 : */
1073 114 : initStringInfo(&querybuf);
1074 114 : initStringInfo(&qualbuf);
1075 228 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1076 114 : "" : "ONLY ";
1077 114 : quoteRelationName(fkrelname, fk_rel);
1078 114 : appendStringInfo(&querybuf, "UPDATE %s%s SET",
1079 : fk_only, fkrelname);
1080 114 : querysep = "";
1081 114 : qualsep = "WHERE";
1082 252 : for (int i = 0, j = riinfo->nkeys; i < riinfo->nkeys; i++, j++)
1083 : {
1084 138 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1085 138 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1086 :
1087 138 : quoteOneName(attname,
1088 138 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1089 138 : appendStringInfo(&querybuf,
1090 : "%s %s = $%d",
1091 : querysep, attname, i + 1);
1092 138 : sprintf(paramname, "$%d", j + 1);
1093 138 : ri_GenerateQual(&qualbuf, qualsep,
1094 : paramname, pk_type,
1095 : riinfo->pf_eq_oprs[i],
1096 : attname, fk_type);
1097 138 : querysep = ",";
1098 138 : qualsep = "AND";
1099 138 : queryoids[i] = pk_type;
1100 138 : queryoids[j] = pk_type;
1101 : }
1102 114 : appendBinaryStringInfo(&querybuf, qualbuf.data, qualbuf.len);
1103 :
1104 : /* Prepare and save the plan */
1105 114 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys * 2, queryoids,
1106 : &qkey, fk_rel, pk_rel);
1107 : }
1108 :
1109 : /*
1110 : * We have a plan now. Run it to update the existing references.
1111 : */
1112 204 : ri_PerformCheck(riinfo, &qkey, qplan,
1113 : fk_rel, pk_rel,
1114 : oldslot, newslot,
1115 : false,
1116 : true, /* must detect new rows */
1117 : SPI_OK_UPDATE);
1118 :
1119 204 : if (SPI_finish() != SPI_OK_FINISH)
1120 0 : elog(ERROR, "SPI_finish failed");
1121 :
1122 204 : table_close(fk_rel, RowExclusiveLock);
1123 :
1124 204 : return PointerGetDatum(NULL);
1125 : }
1126 :
1127 :
1128 : /*
1129 : * RI_FKey_setnull_del -
1130 : *
1131 : * Set foreign key references to NULL values at delete event on PK table.
1132 : */
1133 : Datum
1134 98 : RI_FKey_setnull_del(PG_FUNCTION_ARGS)
1135 : {
1136 : /* Check that this is a valid trigger call on the right time and event. */
1137 98 : ri_CheckTrigger(fcinfo, "RI_FKey_setnull_del", RI_TRIGTYPE_DELETE);
1138 :
1139 : /* Share code with UPDATE case */
1140 98 : return ri_set((TriggerData *) fcinfo->context, true, RI_TRIGTYPE_DELETE);
1141 : }
1142 :
1143 : /*
1144 : * RI_FKey_setnull_upd -
1145 : *
1146 : * Set foreign key references to NULL at update event on PK table.
1147 : */
1148 : Datum
1149 30 : RI_FKey_setnull_upd(PG_FUNCTION_ARGS)
1150 : {
1151 : /* Check that this is a valid trigger call on the right time and event. */
1152 30 : ri_CheckTrigger(fcinfo, "RI_FKey_setnull_upd", RI_TRIGTYPE_UPDATE);
1153 :
1154 : /* Share code with DELETE case */
1155 30 : return ri_set((TriggerData *) fcinfo->context, true, RI_TRIGTYPE_UPDATE);
1156 : }
1157 :
1158 : /*
1159 : * RI_FKey_setdefault_del -
1160 : *
1161 : * Set foreign key references to defaults at delete event on PK table.
1162 : */
1163 : Datum
1164 84 : RI_FKey_setdefault_del(PG_FUNCTION_ARGS)
1165 : {
1166 : /* Check that this is a valid trigger call on the right time and event. */
1167 84 : ri_CheckTrigger(fcinfo, "RI_FKey_setdefault_del", RI_TRIGTYPE_DELETE);
1168 :
1169 : /* Share code with UPDATE case */
1170 84 : return ri_set((TriggerData *) fcinfo->context, false, RI_TRIGTYPE_DELETE);
1171 : }
1172 :
1173 : /*
1174 : * RI_FKey_setdefault_upd -
1175 : *
1176 : * Set foreign key references to defaults at update event on PK table.
1177 : */
1178 : Datum
1179 48 : RI_FKey_setdefault_upd(PG_FUNCTION_ARGS)
1180 : {
1181 : /* Check that this is a valid trigger call on the right time and event. */
1182 48 : ri_CheckTrigger(fcinfo, "RI_FKey_setdefault_upd", RI_TRIGTYPE_UPDATE);
1183 :
1184 : /* Share code with DELETE case */
1185 48 : return ri_set((TriggerData *) fcinfo->context, false, RI_TRIGTYPE_UPDATE);
1186 : }
1187 :
1188 : /*
1189 : * ri_set -
1190 : *
1191 : * Common code for ON DELETE SET NULL, ON DELETE SET DEFAULT, ON UPDATE SET
1192 : * NULL, and ON UPDATE SET DEFAULT.
1193 : */
1194 : static Datum
1195 260 : ri_set(TriggerData *trigdata, bool is_set_null, int tgkind)
1196 : {
1197 : const RI_ConstraintInfo *riinfo;
1198 : Relation fk_rel;
1199 : Relation pk_rel;
1200 : TupleTableSlot *oldslot;
1201 : RI_QueryKey qkey;
1202 : SPIPlanPtr qplan;
1203 : int32 queryno;
1204 :
1205 260 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
1206 : trigdata->tg_relation, true);
1207 :
1208 : /*
1209 : * Get the relation descriptors of the FK and PK tables and the old tuple.
1210 : *
1211 : * fk_rel is opened in RowExclusiveLock mode since that's what our
1212 : * eventual UPDATE will get on it.
1213 : */
1214 260 : fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
1215 260 : pk_rel = trigdata->tg_relation;
1216 260 : oldslot = trigdata->tg_trigslot;
1217 :
1218 260 : SPI_connect();
1219 :
1220 : /*
1221 : * Fetch or prepare a saved plan for the trigger.
1222 : */
1223 260 : switch (tgkind)
1224 : {
1225 78 : case RI_TRIGTYPE_UPDATE:
1226 78 : queryno = is_set_null
1227 : ? RI_PLAN_SETNULL_ONUPDATE
1228 78 : : RI_PLAN_SETDEFAULT_ONUPDATE;
1229 78 : break;
1230 182 : case RI_TRIGTYPE_DELETE:
1231 182 : queryno = is_set_null
1232 : ? RI_PLAN_SETNULL_ONDELETE
1233 182 : : RI_PLAN_SETDEFAULT_ONDELETE;
1234 182 : break;
1235 0 : default:
1236 0 : elog(ERROR, "invalid tgkind passed to ri_set");
1237 : }
1238 :
1239 260 : ri_BuildQueryKey(&qkey, riinfo, queryno);
1240 :
1241 260 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
1242 : {
1243 : StringInfoData querybuf;
1244 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1245 : char attname[MAX_QUOTED_NAME_LEN];
1246 : char paramname[16];
1247 : const char *querysep;
1248 : const char *qualsep;
1249 : Oid queryoids[RI_MAX_NUMKEYS];
1250 : const char *fk_only;
1251 : int num_cols_to_set;
1252 : const int16 *set_cols;
1253 :
1254 162 : switch (tgkind)
1255 : {
1256 54 : case RI_TRIGTYPE_UPDATE:
1257 54 : num_cols_to_set = riinfo->nkeys;
1258 54 : set_cols = riinfo->fk_attnums;
1259 54 : break;
1260 108 : case RI_TRIGTYPE_DELETE:
1261 :
1262 : /*
1263 : * If confdelsetcols are present, then we only update the
1264 : * columns specified in that array, otherwise we update all
1265 : * the referencing columns.
1266 : */
1267 108 : if (riinfo->ndelsetcols != 0)
1268 : {
1269 26 : num_cols_to_set = riinfo->ndelsetcols;
1270 26 : set_cols = riinfo->confdelsetcols;
1271 : }
1272 : else
1273 : {
1274 82 : num_cols_to_set = riinfo->nkeys;
1275 82 : set_cols = riinfo->fk_attnums;
1276 : }
1277 108 : break;
1278 0 : default:
1279 0 : elog(ERROR, "invalid tgkind passed to ri_set");
1280 : }
1281 :
1282 : /* ----------
1283 : * The query string built is
1284 : * UPDATE [ONLY] <fktable> SET fkatt1 = {NULL|DEFAULT} [, ...]
1285 : * WHERE $1 = fkatt1 [AND ...]
1286 : * The type id's for the $ parameters are those of the
1287 : * corresponding PK attributes.
1288 : * ----------
1289 : */
1290 162 : initStringInfo(&querybuf);
1291 324 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1292 162 : "" : "ONLY ";
1293 162 : quoteRelationName(fkrelname, fk_rel);
1294 162 : appendStringInfo(&querybuf, "UPDATE %s%s SET",
1295 : fk_only, fkrelname);
1296 :
1297 : /*
1298 : * Add assignment clauses
1299 : */
1300 162 : querysep = "";
1301 440 : for (int i = 0; i < num_cols_to_set; i++)
1302 : {
1303 278 : quoteOneName(attname, RIAttName(fk_rel, set_cols[i]));
1304 278 : appendStringInfo(&querybuf,
1305 : "%s %s = %s",
1306 : querysep, attname,
1307 : is_set_null ? "NULL" : "DEFAULT");
1308 278 : querysep = ",";
1309 : }
1310 :
1311 : /*
1312 : * Add WHERE clause
1313 : */
1314 162 : qualsep = "WHERE";
1315 466 : for (int i = 0; i < riinfo->nkeys; i++)
1316 : {
1317 304 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1318 304 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1319 :
1320 304 : quoteOneName(attname,
1321 304 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1322 :
1323 304 : sprintf(paramname, "$%d", i + 1);
1324 304 : ri_GenerateQual(&querybuf, qualsep,
1325 : paramname, pk_type,
1326 : riinfo->pf_eq_oprs[i],
1327 : attname, fk_type);
1328 304 : qualsep = "AND";
1329 304 : queryoids[i] = pk_type;
1330 : }
1331 :
1332 : /* Prepare and save the plan */
1333 162 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
1334 : &qkey, fk_rel, pk_rel);
1335 : }
1336 :
1337 : /*
1338 : * We have a plan now. Run it to update the existing references.
1339 : */
1340 260 : ri_PerformCheck(riinfo, &qkey, qplan,
1341 : fk_rel, pk_rel,
1342 : oldslot, NULL,
1343 : false,
1344 : true, /* must detect new rows */
1345 : SPI_OK_UPDATE);
1346 :
1347 258 : if (SPI_finish() != SPI_OK_FINISH)
1348 0 : elog(ERROR, "SPI_finish failed");
1349 :
1350 258 : table_close(fk_rel, RowExclusiveLock);
1351 :
1352 258 : if (is_set_null)
1353 126 : return PointerGetDatum(NULL);
1354 : else
1355 : {
1356 : /*
1357 : * If we just deleted or updated the PK row whose key was equal to the
1358 : * FK columns' default values, and a referencing row exists in the FK
1359 : * table, we would have updated that row to the same values it already
1360 : * had --- and RI_FKey_fk_upd_check_required would hence believe no
1361 : * check is necessary. So we need to do another lookup now and in
1362 : * case a reference still exists, abort the operation. That is
1363 : * already implemented in the NO ACTION trigger, so just run it. (This
1364 : * recheck is only needed in the SET DEFAULT case, since CASCADE would
1365 : * remove such rows in case of a DELETE operation or would change the
1366 : * FK key values in case of an UPDATE, while SET NULL is certain to
1367 : * result in rows that satisfy the FK constraint.)
1368 : */
1369 132 : return ri_restrict(trigdata, true);
1370 : }
1371 : }
1372 :
1373 :
1374 : /*
1375 : * RI_FKey_pk_upd_check_required -
1376 : *
1377 : * Check if we really need to fire the RI trigger for an update or delete to a PK
1378 : * relation. This is called by the AFTER trigger queue manager to see if
1379 : * it can skip queuing an instance of an RI trigger. Returns true if the
1380 : * trigger must be fired, false if we can prove the constraint will still
1381 : * be satisfied.
1382 : *
1383 : * newslot will be NULL if this is called for a delete.
1384 : */
1385 : bool
1386 2500 : RI_FKey_pk_upd_check_required(Trigger *trigger, Relation pk_rel,
1387 : TupleTableSlot *oldslot, TupleTableSlot *newslot)
1388 : {
1389 : const RI_ConstraintInfo *riinfo;
1390 :
1391 2500 : riinfo = ri_FetchConstraintInfo(trigger, pk_rel, true);
1392 :
1393 : /*
1394 : * If any old key value is NULL, the row could not have been referenced by
1395 : * an FK row, so no check is needed.
1396 : */
1397 2500 : if (ri_NullCheck(RelationGetDescr(pk_rel), oldslot, riinfo, true) != RI_KEYS_NONE_NULL)
1398 6 : return false;
1399 :
1400 : /* If all old and new key values are equal, no check is needed */
1401 2494 : if (newslot && ri_KeysEqual(pk_rel, oldslot, newslot, riinfo, true))
1402 536 : return false;
1403 :
1404 : /* Else we need to fire the trigger. */
1405 1958 : return true;
1406 : }
1407 :
1408 : /*
1409 : * RI_FKey_fk_upd_check_required -
1410 : *
1411 : * Check if we really need to fire the RI trigger for an update to an FK
1412 : * relation. This is called by the AFTER trigger queue manager to see if
1413 : * it can skip queuing an instance of an RI trigger. Returns true if the
1414 : * trigger must be fired, false if we can prove the constraint will still
1415 : * be satisfied.
1416 : */
1417 : bool
1418 1080 : RI_FKey_fk_upd_check_required(Trigger *trigger, Relation fk_rel,
1419 : TupleTableSlot *oldslot, TupleTableSlot *newslot)
1420 : {
1421 : const RI_ConstraintInfo *riinfo;
1422 : int ri_nullcheck;
1423 :
1424 : /*
1425 : * AfterTriggerSaveEvent() handles things such that this function is never
1426 : * called for partitioned tables.
1427 : */
1428 : Assert(fk_rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE);
1429 :
1430 1080 : riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1431 :
1432 1080 : ri_nullcheck = ri_NullCheck(RelationGetDescr(fk_rel), newslot, riinfo, false);
1433 :
1434 : /*
1435 : * If all new key values are NULL, the row satisfies the constraint, so no
1436 : * check is needed.
1437 : */
1438 1080 : if (ri_nullcheck == RI_KEYS_ALL_NULL)
1439 126 : return false;
1440 :
1441 : /*
1442 : * If some new key values are NULL, the behavior depends on the match
1443 : * type.
1444 : */
1445 954 : else if (ri_nullcheck == RI_KEYS_SOME_NULL)
1446 : {
1447 30 : switch (riinfo->confmatchtype)
1448 : {
1449 24 : case FKCONSTR_MATCH_SIMPLE:
1450 :
1451 : /*
1452 : * If any new key value is NULL, the row must satisfy the
1453 : * constraint, so no check is needed.
1454 : */
1455 24 : return false;
1456 :
1457 0 : case FKCONSTR_MATCH_PARTIAL:
1458 :
1459 : /*
1460 : * Don't know, must run full check.
1461 : */
1462 0 : break;
1463 :
1464 6 : case FKCONSTR_MATCH_FULL:
1465 :
1466 : /*
1467 : * If some new key values are NULL, the row fails the
1468 : * constraint. We must not throw error here, because the row
1469 : * might get invalidated before the constraint is to be
1470 : * checked, but we should queue the event to apply the check
1471 : * later.
1472 : */
1473 6 : return true;
1474 : }
1475 924 : }
1476 :
1477 : /*
1478 : * Continues here for no new key values are NULL, or we couldn't decide
1479 : * yet.
1480 : */
1481 :
1482 : /*
1483 : * If the original row was inserted by our own transaction, we must fire
1484 : * the trigger whether or not the keys are equal. This is because our
1485 : * UPDATE will invalidate the INSERT so that the INSERT RI trigger will
1486 : * not do anything; so we had better do the UPDATE check. (We could skip
1487 : * this if we knew the INSERT trigger already fired, but there is no easy
1488 : * way to know that.)
1489 : */
1490 924 : if (slot_is_current_xact_tuple(oldslot))
1491 124 : return true;
1492 :
1493 : /* If all old and new key values are equal, no check is needed */
1494 800 : if (ri_KeysEqual(fk_rel, oldslot, newslot, riinfo, false))
1495 464 : return false;
1496 :
1497 : /* Else we need to fire the trigger. */
1498 336 : return true;
1499 : }
1500 :
1501 : /*
1502 : * RI_Initial_Check -
1503 : *
1504 : * Check an entire table for non-matching values using a single query.
1505 : * This is not a trigger procedure, but is called during ALTER TABLE
1506 : * ADD FOREIGN KEY to validate the initial table contents.
1507 : *
1508 : * We expect that the caller has made provision to prevent any problems
1509 : * caused by concurrent actions. This could be either by locking rel and
1510 : * pkrel at ShareRowExclusiveLock or higher, or by otherwise ensuring
1511 : * that triggers implementing the checks are already active.
1512 : * Hence, we do not need to lock individual rows for the check.
1513 : *
1514 : * If the check fails because the current user doesn't have permissions
1515 : * to read both tables, return false to let our caller know that they will
1516 : * need to do something else to check the constraint.
1517 : */
1518 : bool
1519 1004 : RI_Initial_Check(Trigger *trigger, Relation fk_rel, Relation pk_rel)
1520 : {
1521 : const RI_ConstraintInfo *riinfo;
1522 : StringInfoData querybuf;
1523 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
1524 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1525 : char pkattname[MAX_QUOTED_NAME_LEN + 3];
1526 : char fkattname[MAX_QUOTED_NAME_LEN + 3];
1527 : RangeTblEntry *rte;
1528 : RTEPermissionInfo *pk_perminfo;
1529 : RTEPermissionInfo *fk_perminfo;
1530 1004 : List *rtes = NIL;
1531 1004 : List *perminfos = NIL;
1532 : const char *sep;
1533 : const char *fk_only;
1534 : const char *pk_only;
1535 : int save_nestlevel;
1536 : char workmembuf[32];
1537 : int spi_result;
1538 : SPIPlanPtr qplan;
1539 :
1540 1004 : riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1541 :
1542 : /*
1543 : * Check to make sure current user has enough permissions to do the test
1544 : * query. (If not, caller can fall back to the trigger method, which
1545 : * works because it changes user IDs on the fly.)
1546 : *
1547 : * XXX are there any other show-stopper conditions to check?
1548 : */
1549 1004 : pk_perminfo = makeNode(RTEPermissionInfo);
1550 1004 : pk_perminfo->relid = RelationGetRelid(pk_rel);
1551 1004 : pk_perminfo->requiredPerms = ACL_SELECT;
1552 1004 : perminfos = lappend(perminfos, pk_perminfo);
1553 1004 : rte = makeNode(RangeTblEntry);
1554 1004 : rte->rtekind = RTE_RELATION;
1555 1004 : rte->relid = RelationGetRelid(pk_rel);
1556 1004 : rte->relkind = pk_rel->rd_rel->relkind;
1557 1004 : rte->rellockmode = AccessShareLock;
1558 1004 : rte->perminfoindex = list_length(perminfos);
1559 1004 : rtes = lappend(rtes, rte);
1560 :
1561 1004 : fk_perminfo = makeNode(RTEPermissionInfo);
1562 1004 : fk_perminfo->relid = RelationGetRelid(fk_rel);
1563 1004 : fk_perminfo->requiredPerms = ACL_SELECT;
1564 1004 : perminfos = lappend(perminfos, fk_perminfo);
1565 1004 : rte = makeNode(RangeTblEntry);
1566 1004 : rte->rtekind = RTE_RELATION;
1567 1004 : rte->relid = RelationGetRelid(fk_rel);
1568 1004 : rte->relkind = fk_rel->rd_rel->relkind;
1569 1004 : rte->rellockmode = AccessShareLock;
1570 1004 : rte->perminfoindex = list_length(perminfos);
1571 1004 : rtes = lappend(rtes, rte);
1572 :
1573 2364 : for (int i = 0; i < riinfo->nkeys; i++)
1574 : {
1575 : int attno;
1576 :
1577 1360 : attno = riinfo->pk_attnums[i] - FirstLowInvalidHeapAttributeNumber;
1578 1360 : pk_perminfo->selectedCols = bms_add_member(pk_perminfo->selectedCols, attno);
1579 :
1580 1360 : attno = riinfo->fk_attnums[i] - FirstLowInvalidHeapAttributeNumber;
1581 1360 : fk_perminfo->selectedCols = bms_add_member(fk_perminfo->selectedCols, attno);
1582 : }
1583 :
1584 1004 : if (!ExecCheckPermissions(rtes, perminfos, false))
1585 12 : return false;
1586 :
1587 : /*
1588 : * Also punt if RLS is enabled on either table unless this role has the
1589 : * bypassrls right or is the table owner of the table(s) involved which
1590 : * have RLS enabled.
1591 : */
1592 992 : if (!has_bypassrls_privilege(GetUserId()) &&
1593 0 : ((pk_rel->rd_rel->relrowsecurity &&
1594 0 : !object_ownercheck(RelationRelationId, RelationGetRelid(pk_rel),
1595 0 : GetUserId())) ||
1596 0 : (fk_rel->rd_rel->relrowsecurity &&
1597 0 : !object_ownercheck(RelationRelationId, RelationGetRelid(fk_rel),
1598 : GetUserId()))))
1599 0 : return false;
1600 :
1601 : /*----------
1602 : * The query string built is:
1603 : * SELECT fk.keycols FROM [ONLY] relname fk
1604 : * LEFT OUTER JOIN [ONLY] pkrelname pk
1605 : * ON (pk.pkkeycol1=fk.keycol1 [AND ...])
1606 : * WHERE pk.pkkeycol1 IS NULL AND
1607 : * For MATCH SIMPLE:
1608 : * (fk.keycol1 IS NOT NULL [AND ...])
1609 : * For MATCH FULL:
1610 : * (fk.keycol1 IS NOT NULL [OR ...])
1611 : *
1612 : * We attach COLLATE clauses to the operators when comparing columns
1613 : * that have different collations.
1614 : *----------
1615 : */
1616 992 : initStringInfo(&querybuf);
1617 992 : appendStringInfoString(&querybuf, "SELECT ");
1618 992 : sep = "";
1619 2328 : for (int i = 0; i < riinfo->nkeys; i++)
1620 : {
1621 1336 : quoteOneName(fkattname,
1622 1336 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1623 1336 : appendStringInfo(&querybuf, "%sfk.%s", sep, fkattname);
1624 1336 : sep = ", ";
1625 : }
1626 :
1627 992 : quoteRelationName(pkrelname, pk_rel);
1628 992 : quoteRelationName(fkrelname, fk_rel);
1629 1984 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1630 992 : "" : "ONLY ";
1631 1984 : pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1632 992 : "" : "ONLY ";
1633 992 : appendStringInfo(&querybuf,
1634 : " FROM %s%s fk LEFT OUTER JOIN %s%s pk ON",
1635 : fk_only, fkrelname, pk_only, pkrelname);
1636 :
1637 992 : strcpy(pkattname, "pk.");
1638 992 : strcpy(fkattname, "fk.");
1639 992 : sep = "(";
1640 2328 : for (int i = 0; i < riinfo->nkeys; i++)
1641 : {
1642 1336 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1643 1336 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1644 1336 : Oid pk_coll = RIAttCollation(pk_rel, riinfo->pk_attnums[i]);
1645 1336 : Oid fk_coll = RIAttCollation(fk_rel, riinfo->fk_attnums[i]);
1646 :
1647 1336 : quoteOneName(pkattname + 3,
1648 1336 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
1649 1336 : quoteOneName(fkattname + 3,
1650 1336 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1651 1336 : ri_GenerateQual(&querybuf, sep,
1652 : pkattname, pk_type,
1653 : riinfo->pf_eq_oprs[i],
1654 : fkattname, fk_type);
1655 1336 : if (pk_coll != fk_coll)
1656 12 : ri_GenerateQualCollation(&querybuf, pk_coll);
1657 1336 : sep = "AND";
1658 : }
1659 :
1660 : /*
1661 : * It's sufficient to test any one pk attribute for null to detect a join
1662 : * failure.
1663 : */
1664 992 : quoteOneName(pkattname, RIAttName(pk_rel, riinfo->pk_attnums[0]));
1665 992 : appendStringInfo(&querybuf, ") WHERE pk.%s IS NULL AND (", pkattname);
1666 :
1667 992 : sep = "";
1668 2328 : for (int i = 0; i < riinfo->nkeys; i++)
1669 : {
1670 1336 : quoteOneName(fkattname, RIAttName(fk_rel, riinfo->fk_attnums[i]));
1671 1336 : appendStringInfo(&querybuf,
1672 : "%sfk.%s IS NOT NULL",
1673 : sep, fkattname);
1674 1336 : switch (riinfo->confmatchtype)
1675 : {
1676 1236 : case FKCONSTR_MATCH_SIMPLE:
1677 1236 : sep = " AND ";
1678 1236 : break;
1679 100 : case FKCONSTR_MATCH_FULL:
1680 100 : sep = " OR ";
1681 100 : break;
1682 : }
1683 1336 : }
1684 992 : appendStringInfoChar(&querybuf, ')');
1685 :
1686 : /*
1687 : * Temporarily increase work_mem so that the check query can be executed
1688 : * more efficiently. It seems okay to do this because the query is simple
1689 : * enough to not use a multiple of work_mem, and one typically would not
1690 : * have many large foreign-key validations happening concurrently. So
1691 : * this seems to meet the criteria for being considered a "maintenance"
1692 : * operation, and accordingly we use maintenance_work_mem. However, we
1693 : * must also set hash_mem_multiplier to 1, since it is surely not okay to
1694 : * let that get applied to the maintenance_work_mem value.
1695 : *
1696 : * We use the equivalent of a function SET option to allow the setting to
1697 : * persist for exactly the duration of the check query. guc.c also takes
1698 : * care of undoing the setting on error.
1699 : */
1700 992 : save_nestlevel = NewGUCNestLevel();
1701 :
1702 992 : snprintf(workmembuf, sizeof(workmembuf), "%d", maintenance_work_mem);
1703 992 : (void) set_config_option("work_mem", workmembuf,
1704 : PGC_USERSET, PGC_S_SESSION,
1705 : GUC_ACTION_SAVE, true, 0, false);
1706 992 : (void) set_config_option("hash_mem_multiplier", "1",
1707 : PGC_USERSET, PGC_S_SESSION,
1708 : GUC_ACTION_SAVE, true, 0, false);
1709 :
1710 992 : SPI_connect();
1711 :
1712 : /*
1713 : * Generate the plan. We don't need to cache it, and there are no
1714 : * arguments to the plan.
1715 : */
1716 992 : qplan = SPI_prepare(querybuf.data, 0, NULL);
1717 :
1718 992 : if (qplan == NULL)
1719 0 : elog(ERROR, "SPI_prepare returned %s for %s",
1720 : SPI_result_code_string(SPI_result), querybuf.data);
1721 :
1722 : /*
1723 : * Run the plan. For safety we force a current snapshot to be used. (In
1724 : * transaction-snapshot mode, this arguably violates transaction isolation
1725 : * rules, but we really haven't got much choice.) We don't need to
1726 : * register the snapshot, because SPI_execute_snapshot will see to it. We
1727 : * need at most one tuple returned, so pass limit = 1.
1728 : */
1729 992 : spi_result = SPI_execute_snapshot(qplan,
1730 : NULL, NULL,
1731 : GetLatestSnapshot(),
1732 : InvalidSnapshot,
1733 : true, false, 1);
1734 :
1735 : /* Check result */
1736 992 : if (spi_result != SPI_OK_SELECT)
1737 0 : elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
1738 :
1739 : /* Did we find a tuple violating the constraint? */
1740 992 : if (SPI_processed > 0)
1741 : {
1742 : TupleTableSlot *slot;
1743 68 : HeapTuple tuple = SPI_tuptable->vals[0];
1744 68 : TupleDesc tupdesc = SPI_tuptable->tupdesc;
1745 : RI_ConstraintInfo fake_riinfo;
1746 :
1747 68 : slot = MakeSingleTupleTableSlot(tupdesc, &TTSOpsVirtual);
1748 :
1749 68 : heap_deform_tuple(tuple, tupdesc,
1750 : slot->tts_values, slot->tts_isnull);
1751 68 : ExecStoreVirtualTuple(slot);
1752 :
1753 : /*
1754 : * The columns to look at in the result tuple are 1..N, not whatever
1755 : * they are in the fk_rel. Hack up riinfo so that the subroutines
1756 : * called here will behave properly.
1757 : *
1758 : * In addition to this, we have to pass the correct tupdesc to
1759 : * ri_ReportViolation, overriding its normal habit of using the pk_rel
1760 : * or fk_rel's tupdesc.
1761 : */
1762 68 : memcpy(&fake_riinfo, riinfo, sizeof(RI_ConstraintInfo));
1763 160 : for (int i = 0; i < fake_riinfo.nkeys; i++)
1764 92 : fake_riinfo.fk_attnums[i] = i + 1;
1765 :
1766 : /*
1767 : * If it's MATCH FULL, and there are any nulls in the FK keys,
1768 : * complain about that rather than the lack of a match. MATCH FULL
1769 : * disallows partially-null FK rows.
1770 : */
1771 92 : if (fake_riinfo.confmatchtype == FKCONSTR_MATCH_FULL &&
1772 24 : ri_NullCheck(tupdesc, slot, &fake_riinfo, false) != RI_KEYS_NONE_NULL)
1773 12 : ereport(ERROR,
1774 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
1775 : errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
1776 : RelationGetRelationName(fk_rel),
1777 : NameStr(fake_riinfo.conname)),
1778 : errdetail("MATCH FULL does not allow mixing of null and nonnull key values."),
1779 : errtableconstraint(fk_rel,
1780 : NameStr(fake_riinfo.conname))));
1781 :
1782 : /*
1783 : * We tell ri_ReportViolation we were doing the RI_PLAN_CHECK_LOOKUPPK
1784 : * query, which isn't true, but will cause it to use
1785 : * fake_riinfo.fk_attnums as we need.
1786 : */
1787 56 : ri_ReportViolation(&fake_riinfo,
1788 : pk_rel, fk_rel,
1789 : slot, tupdesc,
1790 : RI_PLAN_CHECK_LOOKUPPK, false, false);
1791 :
1792 : ExecDropSingleTupleTableSlot(slot);
1793 : }
1794 :
1795 924 : if (SPI_finish() != SPI_OK_FINISH)
1796 0 : elog(ERROR, "SPI_finish failed");
1797 :
1798 : /*
1799 : * Restore work_mem and hash_mem_multiplier.
1800 : */
1801 924 : AtEOXact_GUC(true, save_nestlevel);
1802 :
1803 924 : return true;
1804 : }
1805 :
1806 : /*
1807 : * RI_PartitionRemove_Check -
1808 : *
1809 : * Verify no referencing values exist, when a partition is detached on
1810 : * the referenced side of a foreign key constraint.
1811 : */
1812 : void
1813 86 : RI_PartitionRemove_Check(Trigger *trigger, Relation fk_rel, Relation pk_rel)
1814 : {
1815 : const RI_ConstraintInfo *riinfo;
1816 : StringInfoData querybuf;
1817 : char *constraintDef;
1818 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
1819 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1820 : char pkattname[MAX_QUOTED_NAME_LEN + 3];
1821 : char fkattname[MAX_QUOTED_NAME_LEN + 3];
1822 : const char *sep;
1823 : const char *fk_only;
1824 : int save_nestlevel;
1825 : char workmembuf[32];
1826 : int spi_result;
1827 : SPIPlanPtr qplan;
1828 : int i;
1829 :
1830 86 : riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1831 :
1832 : /*
1833 : * We don't check permissions before displaying the error message, on the
1834 : * assumption that the user detaching the partition must have enough
1835 : * privileges to examine the table contents anyhow.
1836 : */
1837 :
1838 : /*----------
1839 : * The query string built is:
1840 : * SELECT fk.keycols FROM [ONLY] relname fk
1841 : * JOIN pkrelname pk
1842 : * ON (pk.pkkeycol1=fk.keycol1 [AND ...])
1843 : * WHERE (<partition constraint>) AND
1844 : * For MATCH SIMPLE:
1845 : * (fk.keycol1 IS NOT NULL [AND ...])
1846 : * For MATCH FULL:
1847 : * (fk.keycol1 IS NOT NULL [OR ...])
1848 : *
1849 : * We attach COLLATE clauses to the operators when comparing columns
1850 : * that have different collations.
1851 : *----------
1852 : */
1853 86 : initStringInfo(&querybuf);
1854 86 : appendStringInfoString(&querybuf, "SELECT ");
1855 86 : sep = "";
1856 172 : for (i = 0; i < riinfo->nkeys; i++)
1857 : {
1858 86 : quoteOneName(fkattname,
1859 86 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1860 86 : appendStringInfo(&querybuf, "%sfk.%s", sep, fkattname);
1861 86 : sep = ", ";
1862 : }
1863 :
1864 86 : quoteRelationName(pkrelname, pk_rel);
1865 86 : quoteRelationName(fkrelname, fk_rel);
1866 172 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1867 86 : "" : "ONLY ";
1868 86 : appendStringInfo(&querybuf,
1869 : " FROM %s%s fk JOIN %s pk ON",
1870 : fk_only, fkrelname, pkrelname);
1871 86 : strcpy(pkattname, "pk.");
1872 86 : strcpy(fkattname, "fk.");
1873 86 : sep = "(";
1874 172 : for (i = 0; i < riinfo->nkeys; i++)
1875 : {
1876 86 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1877 86 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1878 86 : Oid pk_coll = RIAttCollation(pk_rel, riinfo->pk_attnums[i]);
1879 86 : Oid fk_coll = RIAttCollation(fk_rel, riinfo->fk_attnums[i]);
1880 :
1881 86 : quoteOneName(pkattname + 3,
1882 86 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
1883 86 : quoteOneName(fkattname + 3,
1884 86 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1885 86 : ri_GenerateQual(&querybuf, sep,
1886 : pkattname, pk_type,
1887 : riinfo->pf_eq_oprs[i],
1888 : fkattname, fk_type);
1889 86 : if (pk_coll != fk_coll)
1890 0 : ri_GenerateQualCollation(&querybuf, pk_coll);
1891 86 : sep = "AND";
1892 : }
1893 :
1894 : /*
1895 : * Start the WHERE clause with the partition constraint (except if this is
1896 : * the default partition and there's no other partition, because the
1897 : * partition constraint is the empty string in that case.)
1898 : */
1899 86 : constraintDef = pg_get_partconstrdef_string(RelationGetRelid(pk_rel), "pk");
1900 86 : if (constraintDef && constraintDef[0] != '\0')
1901 86 : appendStringInfo(&querybuf, ") WHERE %s AND (",
1902 : constraintDef);
1903 : else
1904 0 : appendStringInfoString(&querybuf, ") WHERE (");
1905 :
1906 86 : sep = "";
1907 172 : for (i = 0; i < riinfo->nkeys; i++)
1908 : {
1909 86 : quoteOneName(fkattname, RIAttName(fk_rel, riinfo->fk_attnums[i]));
1910 86 : appendStringInfo(&querybuf,
1911 : "%sfk.%s IS NOT NULL",
1912 : sep, fkattname);
1913 86 : switch (riinfo->confmatchtype)
1914 : {
1915 86 : case FKCONSTR_MATCH_SIMPLE:
1916 86 : sep = " AND ";
1917 86 : break;
1918 0 : case FKCONSTR_MATCH_FULL:
1919 0 : sep = " OR ";
1920 0 : break;
1921 : }
1922 86 : }
1923 86 : appendStringInfoChar(&querybuf, ')');
1924 :
1925 : /*
1926 : * Temporarily increase work_mem so that the check query can be executed
1927 : * more efficiently. It seems okay to do this because the query is simple
1928 : * enough to not use a multiple of work_mem, and one typically would not
1929 : * have many large foreign-key validations happening concurrently. So
1930 : * this seems to meet the criteria for being considered a "maintenance"
1931 : * operation, and accordingly we use maintenance_work_mem. However, we
1932 : * must also set hash_mem_multiplier to 1, since it is surely not okay to
1933 : * let that get applied to the maintenance_work_mem value.
1934 : *
1935 : * We use the equivalent of a function SET option to allow the setting to
1936 : * persist for exactly the duration of the check query. guc.c also takes
1937 : * care of undoing the setting on error.
1938 : */
1939 86 : save_nestlevel = NewGUCNestLevel();
1940 :
1941 86 : snprintf(workmembuf, sizeof(workmembuf), "%d", maintenance_work_mem);
1942 86 : (void) set_config_option("work_mem", workmembuf,
1943 : PGC_USERSET, PGC_S_SESSION,
1944 : GUC_ACTION_SAVE, true, 0, false);
1945 86 : (void) set_config_option("hash_mem_multiplier", "1",
1946 : PGC_USERSET, PGC_S_SESSION,
1947 : GUC_ACTION_SAVE, true, 0, false);
1948 :
1949 86 : SPI_connect();
1950 :
1951 : /*
1952 : * Generate the plan. We don't need to cache it, and there are no
1953 : * arguments to the plan.
1954 : */
1955 86 : qplan = SPI_prepare(querybuf.data, 0, NULL);
1956 :
1957 86 : if (qplan == NULL)
1958 0 : elog(ERROR, "SPI_prepare returned %s for %s",
1959 : SPI_result_code_string(SPI_result), querybuf.data);
1960 :
1961 : /*
1962 : * Run the plan. For safety we force a current snapshot to be used. (In
1963 : * transaction-snapshot mode, this arguably violates transaction isolation
1964 : * rules, but we really haven't got much choice.) We don't need to
1965 : * register the snapshot, because SPI_execute_snapshot will see to it. We
1966 : * need at most one tuple returned, so pass limit = 1.
1967 : */
1968 86 : spi_result = SPI_execute_snapshot(qplan,
1969 : NULL, NULL,
1970 : GetLatestSnapshot(),
1971 : InvalidSnapshot,
1972 : true, false, 1);
1973 :
1974 : /* Check result */
1975 86 : if (spi_result != SPI_OK_SELECT)
1976 0 : elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
1977 :
1978 : /* Did we find a tuple that would violate the constraint? */
1979 86 : if (SPI_processed > 0)
1980 : {
1981 : TupleTableSlot *slot;
1982 34 : HeapTuple tuple = SPI_tuptable->vals[0];
1983 34 : TupleDesc tupdesc = SPI_tuptable->tupdesc;
1984 : RI_ConstraintInfo fake_riinfo;
1985 :
1986 34 : slot = MakeSingleTupleTableSlot(tupdesc, &TTSOpsVirtual);
1987 :
1988 34 : heap_deform_tuple(tuple, tupdesc,
1989 : slot->tts_values, slot->tts_isnull);
1990 34 : ExecStoreVirtualTuple(slot);
1991 :
1992 : /*
1993 : * The columns to look at in the result tuple are 1..N, not whatever
1994 : * they are in the fk_rel. Hack up riinfo so that ri_ReportViolation
1995 : * will behave properly.
1996 : *
1997 : * In addition to this, we have to pass the correct tupdesc to
1998 : * ri_ReportViolation, overriding its normal habit of using the pk_rel
1999 : * or fk_rel's tupdesc.
2000 : */
2001 34 : memcpy(&fake_riinfo, riinfo, sizeof(RI_ConstraintInfo));
2002 68 : for (i = 0; i < fake_riinfo.nkeys; i++)
2003 34 : fake_riinfo.pk_attnums[i] = i + 1;
2004 :
2005 34 : ri_ReportViolation(&fake_riinfo, pk_rel, fk_rel,
2006 : slot, tupdesc, 0, false, true);
2007 : }
2008 :
2009 52 : if (SPI_finish() != SPI_OK_FINISH)
2010 0 : elog(ERROR, "SPI_finish failed");
2011 :
2012 : /*
2013 : * Restore work_mem and hash_mem_multiplier.
2014 : */
2015 52 : AtEOXact_GUC(true, save_nestlevel);
2016 52 : }
2017 :
2018 :
2019 : /* ----------
2020 : * Local functions below
2021 : * ----------
2022 : */
2023 :
2024 :
2025 : /*
2026 : * quoteOneName --- safely quote a single SQL name
2027 : *
2028 : * buffer must be MAX_QUOTED_NAME_LEN long (includes room for \0)
2029 : */
2030 : static void
2031 23360 : quoteOneName(char *buffer, const char *name)
2032 : {
2033 : /* Rather than trying to be smart, just always quote it. */
2034 23360 : *buffer++ = '"';
2035 149432 : while (*name)
2036 : {
2037 126072 : if (*name == '"')
2038 0 : *buffer++ = '"';
2039 126072 : *buffer++ = *name++;
2040 : }
2041 23360 : *buffer++ = '"';
2042 23360 : *buffer = '\0';
2043 23360 : }
2044 :
2045 : /*
2046 : * quoteRelationName --- safely quote a fully qualified relation name
2047 : *
2048 : * buffer must be MAX_QUOTED_REL_NAME_LEN long (includes room for \0)
2049 : */
2050 : static void
2051 5672 : quoteRelationName(char *buffer, Relation rel)
2052 : {
2053 5672 : quoteOneName(buffer, get_namespace_name(RelationGetNamespace(rel)));
2054 5672 : buffer += strlen(buffer);
2055 5672 : *buffer++ = '.';
2056 5672 : quoteOneName(buffer, RelationGetRelationName(rel));
2057 5672 : }
2058 :
2059 : /*
2060 : * ri_GenerateQual --- generate a WHERE clause equating two variables
2061 : *
2062 : * This basically appends " sep leftop op rightop" to buf, adding casts
2063 : * and schema qualification as needed to ensure that the parser will select
2064 : * the operator we specify. leftop and rightop should be parenthesized
2065 : * if they aren't variables or parameters.
2066 : */
2067 : static void
2068 6456 : ri_GenerateQual(StringInfo buf,
2069 : const char *sep,
2070 : const char *leftop, Oid leftoptype,
2071 : Oid opoid,
2072 : const char *rightop, Oid rightoptype)
2073 : {
2074 6456 : appendStringInfo(buf, " %s ", sep);
2075 6456 : generate_operator_clause(buf, leftop, leftoptype, opoid,
2076 : rightop, rightoptype);
2077 6456 : }
2078 :
2079 : /*
2080 : * ri_GenerateQualCollation --- add a COLLATE spec to a WHERE clause
2081 : *
2082 : * We only have to use this function when directly comparing the referencing
2083 : * and referenced columns, if they are of different collations; else the
2084 : * parser will fail to resolve the collation to use. We don't need to use
2085 : * this function for RI queries that compare a variable to a $n parameter.
2086 : * Since parameter symbols always have default collation, the effect will be
2087 : * to use the variable's collation.
2088 : *
2089 : * Note that we require that the collations of the referencing and the
2090 : * referenced column have the same notion of equality: Either they have to
2091 : * both be deterministic or else they both have to be the same. (See also
2092 : * ATAddForeignKeyConstraint().)
2093 : */
2094 : static void
2095 12 : ri_GenerateQualCollation(StringInfo buf, Oid collation)
2096 : {
2097 : HeapTuple tp;
2098 : Form_pg_collation colltup;
2099 : char *collname;
2100 : char onename[MAX_QUOTED_NAME_LEN];
2101 :
2102 : /* Nothing to do if it's a noncollatable data type */
2103 12 : if (!OidIsValid(collation))
2104 0 : return;
2105 :
2106 12 : tp = SearchSysCache1(COLLOID, ObjectIdGetDatum(collation));
2107 12 : if (!HeapTupleIsValid(tp))
2108 0 : elog(ERROR, "cache lookup failed for collation %u", collation);
2109 12 : colltup = (Form_pg_collation) GETSTRUCT(tp);
2110 12 : collname = NameStr(colltup->collname);
2111 :
2112 : /*
2113 : * We qualify the name always, for simplicity and to ensure the query is
2114 : * not search-path-dependent.
2115 : */
2116 12 : quoteOneName(onename, get_namespace_name(colltup->collnamespace));
2117 12 : appendStringInfo(buf, " COLLATE %s", onename);
2118 12 : quoteOneName(onename, collname);
2119 12 : appendStringInfo(buf, ".%s", onename);
2120 :
2121 12 : ReleaseSysCache(tp);
2122 : }
2123 :
2124 : /* ----------
2125 : * ri_BuildQueryKey -
2126 : *
2127 : * Construct a hashtable key for a prepared SPI plan of an FK constraint.
2128 : *
2129 : * key: output argument, *key is filled in based on the other arguments
2130 : * riinfo: info derived from pg_constraint entry
2131 : * constr_queryno: an internal number identifying the query type
2132 : * (see RI_PLAN_XXX constants at head of file)
2133 : * ----------
2134 : */
2135 : static void
2136 6774 : ri_BuildQueryKey(RI_QueryKey *key, const RI_ConstraintInfo *riinfo,
2137 : int32 constr_queryno)
2138 : {
2139 : /*
2140 : * Inherited constraints with a common ancestor can share ri_query_cache
2141 : * entries for all query types except RI_PLAN_CHECK_LOOKUPPK_FROM_PK.
2142 : * Except in that case, the query processes the other table involved in
2143 : * the FK constraint (i.e., not the table on which the trigger has been
2144 : * fired), and so it will be the same for all members of the inheritance
2145 : * tree. So we may use the root constraint's OID in the hash key, rather
2146 : * than the constraint's own OID. This avoids creating duplicate SPI
2147 : * plans, saving lots of work and memory when there are many partitions
2148 : * with similar FK constraints.
2149 : *
2150 : * (Note that we must still have a separate RI_ConstraintInfo for each
2151 : * constraint, because partitions can have different column orders,
2152 : * resulting in different pk_attnums[] or fk_attnums[] array contents.)
2153 : *
2154 : * We assume struct RI_QueryKey contains no padding bytes, else we'd need
2155 : * to use memset to clear them.
2156 : */
2157 6774 : if (constr_queryno != RI_PLAN_CHECK_LOOKUPPK_FROM_PK)
2158 6012 : key->constr_id = riinfo->constraint_root_id;
2159 : else
2160 762 : key->constr_id = riinfo->constraint_id;
2161 6774 : key->constr_queryno = constr_queryno;
2162 6774 : }
2163 :
2164 : /*
2165 : * Check that RI trigger function was called in expected context
2166 : */
2167 : static void
2168 6286 : ri_CheckTrigger(FunctionCallInfo fcinfo, const char *funcname, int tgkind)
2169 : {
2170 6286 : TriggerData *trigdata = (TriggerData *) fcinfo->context;
2171 :
2172 6286 : if (!CALLED_AS_TRIGGER(fcinfo))
2173 0 : ereport(ERROR,
2174 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2175 : errmsg("function \"%s\" was not called by trigger manager", funcname)));
2176 :
2177 : /*
2178 : * Check proper event
2179 : */
2180 6286 : if (!TRIGGER_FIRED_AFTER(trigdata->tg_event) ||
2181 6286 : !TRIGGER_FIRED_FOR_ROW(trigdata->tg_event))
2182 0 : ereport(ERROR,
2183 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2184 : errmsg("function \"%s\" must be fired AFTER ROW", funcname)));
2185 :
2186 6286 : switch (tgkind)
2187 : {
2188 4086 : case RI_TRIGTYPE_INSERT:
2189 4086 : if (!TRIGGER_FIRED_BY_INSERT(trigdata->tg_event))
2190 0 : ereport(ERROR,
2191 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2192 : errmsg("function \"%s\" must be fired for INSERT", funcname)));
2193 4086 : break;
2194 1354 : case RI_TRIGTYPE_UPDATE:
2195 1354 : if (!TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
2196 0 : ereport(ERROR,
2197 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2198 : errmsg("function \"%s\" must be fired for UPDATE", funcname)));
2199 1354 : break;
2200 846 : case RI_TRIGTYPE_DELETE:
2201 846 : if (!TRIGGER_FIRED_BY_DELETE(trigdata->tg_event))
2202 0 : ereport(ERROR,
2203 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2204 : errmsg("function \"%s\" must be fired for DELETE", funcname)));
2205 846 : break;
2206 : }
2207 6286 : }
2208 :
2209 :
2210 : /*
2211 : * Fetch the RI_ConstraintInfo struct for the trigger's FK constraint.
2212 : */
2213 : static const RI_ConstraintInfo *
2214 11088 : ri_FetchConstraintInfo(Trigger *trigger, Relation trig_rel, bool rel_is_pk)
2215 : {
2216 11088 : Oid constraintOid = trigger->tgconstraint;
2217 : const RI_ConstraintInfo *riinfo;
2218 :
2219 : /*
2220 : * Check that the FK constraint's OID is available; it might not be if
2221 : * we've been invoked via an ordinary trigger or an old-style "constraint
2222 : * trigger".
2223 : */
2224 11088 : if (!OidIsValid(constraintOid))
2225 0 : ereport(ERROR,
2226 : (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
2227 : errmsg("no pg_constraint entry for trigger \"%s\" on table \"%s\"",
2228 : trigger->tgname, RelationGetRelationName(trig_rel)),
2229 : errhint("Remove this referential integrity trigger and its mates, then do ALTER TABLE ADD CONSTRAINT.")));
2230 :
2231 : /* Find or create a hashtable entry for the constraint */
2232 11088 : riinfo = ri_LoadConstraintInfo(constraintOid);
2233 :
2234 : /* Do some easy cross-checks against the trigger call data */
2235 11088 : if (rel_is_pk)
2236 : {
2237 4384 : if (riinfo->fk_relid != trigger->tgconstrrelid ||
2238 4384 : riinfo->pk_relid != RelationGetRelid(trig_rel))
2239 0 : elog(ERROR, "wrong pg_constraint entry for trigger \"%s\" on table \"%s\"",
2240 : trigger->tgname, RelationGetRelationName(trig_rel));
2241 : }
2242 : else
2243 : {
2244 6704 : if (riinfo->fk_relid != RelationGetRelid(trig_rel) ||
2245 6704 : riinfo->pk_relid != trigger->tgconstrrelid)
2246 0 : elog(ERROR, "wrong pg_constraint entry for trigger \"%s\" on table \"%s\"",
2247 : trigger->tgname, RelationGetRelationName(trig_rel));
2248 : }
2249 :
2250 11088 : if (riinfo->confmatchtype != FKCONSTR_MATCH_FULL &&
2251 10624 : riinfo->confmatchtype != FKCONSTR_MATCH_PARTIAL &&
2252 10624 : riinfo->confmatchtype != FKCONSTR_MATCH_SIMPLE)
2253 0 : elog(ERROR, "unrecognized confmatchtype: %d",
2254 : riinfo->confmatchtype);
2255 :
2256 11088 : if (riinfo->confmatchtype == FKCONSTR_MATCH_PARTIAL)
2257 0 : ereport(ERROR,
2258 : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2259 : errmsg("MATCH PARTIAL not yet implemented")));
2260 :
2261 11088 : return riinfo;
2262 : }
2263 :
2264 : /*
2265 : * Fetch or create the RI_ConstraintInfo struct for an FK constraint.
2266 : */
2267 : static const RI_ConstraintInfo *
2268 11088 : ri_LoadConstraintInfo(Oid constraintOid)
2269 : {
2270 : RI_ConstraintInfo *riinfo;
2271 : bool found;
2272 : HeapTuple tup;
2273 : Form_pg_constraint conForm;
2274 :
2275 : /*
2276 : * On the first call initialize the hashtable
2277 : */
2278 11088 : if (!ri_constraint_cache)
2279 422 : ri_InitHashTables();
2280 :
2281 : /*
2282 : * Find or create a hash entry. If we find a valid one, just return it.
2283 : */
2284 11088 : riinfo = (RI_ConstraintInfo *) hash_search(ri_constraint_cache,
2285 : &constraintOid,
2286 : HASH_ENTER, &found);
2287 11088 : if (!found)
2288 3880 : riinfo->valid = false;
2289 7208 : else if (riinfo->valid)
2290 6888 : return riinfo;
2291 :
2292 : /*
2293 : * Fetch the pg_constraint row so we can fill in the entry.
2294 : */
2295 4200 : tup = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constraintOid));
2296 4200 : if (!HeapTupleIsValid(tup)) /* should not happen */
2297 0 : elog(ERROR, "cache lookup failed for constraint %u", constraintOid);
2298 4200 : conForm = (Form_pg_constraint) GETSTRUCT(tup);
2299 :
2300 4200 : if (conForm->contype != CONSTRAINT_FOREIGN) /* should not happen */
2301 0 : elog(ERROR, "constraint %u is not a foreign key constraint",
2302 : constraintOid);
2303 :
2304 : /* And extract data */
2305 : Assert(riinfo->constraint_id == constraintOid);
2306 4200 : if (OidIsValid(conForm->conparentid))
2307 1452 : riinfo->constraint_root_id =
2308 1452 : get_ri_constraint_root(conForm->conparentid);
2309 : else
2310 2748 : riinfo->constraint_root_id = constraintOid;
2311 4200 : riinfo->oidHashValue = GetSysCacheHashValue1(CONSTROID,
2312 : ObjectIdGetDatum(constraintOid));
2313 4200 : riinfo->rootHashValue = GetSysCacheHashValue1(CONSTROID,
2314 : ObjectIdGetDatum(riinfo->constraint_root_id));
2315 4200 : memcpy(&riinfo->conname, &conForm->conname, sizeof(NameData));
2316 4200 : riinfo->pk_relid = conForm->confrelid;
2317 4200 : riinfo->fk_relid = conForm->conrelid;
2318 4200 : riinfo->confupdtype = conForm->confupdtype;
2319 4200 : riinfo->confdeltype = conForm->confdeltype;
2320 4200 : riinfo->confmatchtype = conForm->confmatchtype;
2321 4200 : riinfo->hasperiod = conForm->conperiod;
2322 :
2323 4200 : DeconstructFkConstraintRow(tup,
2324 : &riinfo->nkeys,
2325 4200 : riinfo->fk_attnums,
2326 4200 : riinfo->pk_attnums,
2327 4200 : riinfo->pf_eq_oprs,
2328 4200 : riinfo->pp_eq_oprs,
2329 4200 : riinfo->ff_eq_oprs,
2330 : &riinfo->ndelsetcols,
2331 4200 : riinfo->confdelsetcols);
2332 :
2333 : /*
2334 : * For temporal FKs, get the operators and functions we need. We ask the
2335 : * opclass of the PK element for these. This all gets cached (as does the
2336 : * generated plan), so there's no performance issue.
2337 : */
2338 4200 : if (riinfo->hasperiod)
2339 : {
2340 254 : Oid opclass = get_index_column_opclass(conForm->conindid, riinfo->nkeys);
2341 :
2342 254 : FindFKPeriodOpers(opclass,
2343 : &riinfo->period_contained_by_oper,
2344 : &riinfo->agged_period_contained_by_oper,
2345 : &riinfo->period_intersect_oper);
2346 : }
2347 :
2348 4200 : ReleaseSysCache(tup);
2349 :
2350 : /*
2351 : * For efficient processing of invalidation messages below, we keep a
2352 : * doubly-linked count list of all currently valid entries.
2353 : */
2354 4200 : dclist_push_tail(&ri_constraint_cache_valid_list, &riinfo->valid_link);
2355 :
2356 4200 : riinfo->valid = true;
2357 :
2358 4200 : return riinfo;
2359 : }
2360 :
2361 : /*
2362 : * get_ri_constraint_root
2363 : * Returns the OID of the constraint's root parent
2364 : */
2365 : static Oid
2366 1774 : get_ri_constraint_root(Oid constrOid)
2367 : {
2368 : for (;;)
2369 322 : {
2370 : HeapTuple tuple;
2371 : Oid constrParentOid;
2372 :
2373 1774 : tuple = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constrOid));
2374 1774 : if (!HeapTupleIsValid(tuple))
2375 0 : elog(ERROR, "cache lookup failed for constraint %u", constrOid);
2376 1774 : constrParentOid = ((Form_pg_constraint) GETSTRUCT(tuple))->conparentid;
2377 1774 : ReleaseSysCache(tuple);
2378 1774 : if (!OidIsValid(constrParentOid))
2379 1452 : break; /* we reached the root constraint */
2380 322 : constrOid = constrParentOid;
2381 : }
2382 1452 : return constrOid;
2383 : }
2384 :
2385 : /*
2386 : * Callback for pg_constraint inval events
2387 : *
2388 : * While most syscache callbacks just flush all their entries, pg_constraint
2389 : * gets enough update traffic that it's probably worth being smarter.
2390 : * Invalidate any ri_constraint_cache entry associated with the syscache
2391 : * entry with the specified hash value, or all entries if hashvalue == 0.
2392 : *
2393 : * Note: at the time a cache invalidation message is processed there may be
2394 : * active references to the cache. Because of this we never remove entries
2395 : * from the cache, but only mark them invalid, which is harmless to active
2396 : * uses. (Any query using an entry should hold a lock sufficient to keep that
2397 : * data from changing under it --- but we may get cache flushes anyway.)
2398 : */
2399 : static void
2400 74506 : InvalidateConstraintCacheCallBack(Datum arg, int cacheid, uint32 hashvalue)
2401 : {
2402 : dlist_mutable_iter iter;
2403 :
2404 : Assert(ri_constraint_cache != NULL);
2405 :
2406 : /*
2407 : * If the list of currently valid entries gets excessively large, we mark
2408 : * them all invalid so we can empty the list. This arrangement avoids
2409 : * O(N^2) behavior in situations where a session touches many foreign keys
2410 : * and also does many ALTER TABLEs, such as a restore from pg_dump.
2411 : */
2412 74506 : if (dclist_count(&ri_constraint_cache_valid_list) > 1000)
2413 0 : hashvalue = 0; /* pretend it's a cache reset */
2414 :
2415 274508 : dclist_foreach_modify(iter, &ri_constraint_cache_valid_list)
2416 : {
2417 200002 : RI_ConstraintInfo *riinfo = dclist_container(RI_ConstraintInfo,
2418 : valid_link, iter.cur);
2419 :
2420 : /*
2421 : * We must invalidate not only entries directly matching the given
2422 : * hash value, but also child entries, in case the invalidation
2423 : * affects a root constraint.
2424 : */
2425 200002 : if (hashvalue == 0 ||
2426 199942 : riinfo->oidHashValue == hashvalue ||
2427 197376 : riinfo->rootHashValue == hashvalue)
2428 : {
2429 2872 : riinfo->valid = false;
2430 : /* Remove invalidated entries from the list, too */
2431 2872 : dclist_delete_from(&ri_constraint_cache_valid_list, iter.cur);
2432 : }
2433 : }
2434 74506 : }
2435 :
2436 :
2437 : /*
2438 : * Prepare execution plan for a query to enforce an RI restriction
2439 : */
2440 : static SPIPlanPtr
2441 3388 : ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
2442 : RI_QueryKey *qkey, Relation fk_rel, Relation pk_rel)
2443 : {
2444 : SPIPlanPtr qplan;
2445 : Relation query_rel;
2446 : Oid save_userid;
2447 : int save_sec_context;
2448 :
2449 : /*
2450 : * Use the query type code to determine whether the query is run against
2451 : * the PK or FK table; we'll do the check as that table's owner
2452 : */
2453 3388 : if (qkey->constr_queryno <= RI_PLAN_LAST_ON_PK)
2454 2514 : query_rel = pk_rel;
2455 : else
2456 874 : query_rel = fk_rel;
2457 :
2458 : /* Switch to proper UID to perform check as */
2459 3388 : GetUserIdAndSecContext(&save_userid, &save_sec_context);
2460 3388 : SetUserIdAndSecContext(RelationGetForm(query_rel)->relowner,
2461 : save_sec_context | SECURITY_LOCAL_USERID_CHANGE |
2462 : SECURITY_NOFORCE_RLS);
2463 :
2464 : /* Create the plan */
2465 3388 : qplan = SPI_prepare(querystr, nargs, argtypes);
2466 :
2467 3388 : if (qplan == NULL)
2468 0 : elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), querystr);
2469 :
2470 : /* Restore UID and security context */
2471 3388 : SetUserIdAndSecContext(save_userid, save_sec_context);
2472 :
2473 : /* Save the plan */
2474 3388 : SPI_keepplan(qplan);
2475 3388 : ri_HashPreparedPlan(qkey, qplan);
2476 :
2477 3388 : return qplan;
2478 : }
2479 :
2480 : /*
2481 : * Perform a query to enforce an RI restriction
2482 : */
2483 : static bool
2484 6774 : ri_PerformCheck(const RI_ConstraintInfo *riinfo,
2485 : RI_QueryKey *qkey, SPIPlanPtr qplan,
2486 : Relation fk_rel, Relation pk_rel,
2487 : TupleTableSlot *oldslot, TupleTableSlot *newslot,
2488 : bool is_restrict,
2489 : bool detectNewRows, int expect_OK)
2490 : {
2491 : Relation query_rel,
2492 : source_rel;
2493 : bool source_is_pk;
2494 : Snapshot test_snapshot;
2495 : Snapshot crosscheck_snapshot;
2496 : int limit;
2497 : int spi_result;
2498 : Oid save_userid;
2499 : int save_sec_context;
2500 : Datum vals[RI_MAX_NUMKEYS * 2];
2501 : char nulls[RI_MAX_NUMKEYS * 2];
2502 :
2503 : /*
2504 : * Use the query type code to determine whether the query is run against
2505 : * the PK or FK table; we'll do the check as that table's owner
2506 : */
2507 6774 : if (qkey->constr_queryno <= RI_PLAN_LAST_ON_PK)
2508 4948 : query_rel = pk_rel;
2509 : else
2510 1826 : query_rel = fk_rel;
2511 :
2512 : /*
2513 : * The values for the query are taken from the table on which the trigger
2514 : * is called - it is normally the other one with respect to query_rel. An
2515 : * exception is ri_Check_Pk_Match(), which uses the PK table for both (and
2516 : * sets queryno to RI_PLAN_CHECK_LOOKUPPK_FROM_PK). We might eventually
2517 : * need some less klugy way to determine this.
2518 : */
2519 6774 : if (qkey->constr_queryno == RI_PLAN_CHECK_LOOKUPPK)
2520 : {
2521 4186 : source_rel = fk_rel;
2522 4186 : source_is_pk = false;
2523 : }
2524 : else
2525 : {
2526 2588 : source_rel = pk_rel;
2527 2588 : source_is_pk = true;
2528 : }
2529 :
2530 : /* Extract the parameters to be passed into the query */
2531 6774 : if (newslot)
2532 : {
2533 4390 : ri_ExtractValues(source_rel, newslot, riinfo, source_is_pk,
2534 : vals, nulls);
2535 4390 : if (oldslot)
2536 204 : ri_ExtractValues(source_rel, oldslot, riinfo, source_is_pk,
2537 204 : vals + riinfo->nkeys, nulls + riinfo->nkeys);
2538 : }
2539 : else
2540 : {
2541 2384 : ri_ExtractValues(source_rel, oldslot, riinfo, source_is_pk,
2542 : vals, nulls);
2543 : }
2544 :
2545 : /*
2546 : * In READ COMMITTED mode, we just need to use an up-to-date regular
2547 : * snapshot, and we will see all rows that could be interesting. But in
2548 : * transaction-snapshot mode, we can't change the transaction snapshot. If
2549 : * the caller passes detectNewRows == false then it's okay to do the query
2550 : * with the transaction snapshot; otherwise we use a current snapshot, and
2551 : * tell the executor to error out if it finds any rows under the current
2552 : * snapshot that wouldn't be visible per the transaction snapshot. Note
2553 : * that SPI_execute_snapshot will register the snapshots, so we don't need
2554 : * to bother here.
2555 : */
2556 6774 : if (IsolationUsesXactSnapshot() && detectNewRows)
2557 : {
2558 32 : CommandCounterIncrement(); /* be sure all my own work is visible */
2559 32 : test_snapshot = GetLatestSnapshot();
2560 32 : crosscheck_snapshot = GetTransactionSnapshot();
2561 : }
2562 : else
2563 : {
2564 : /* the default SPI behavior is okay */
2565 6742 : test_snapshot = InvalidSnapshot;
2566 6742 : crosscheck_snapshot = InvalidSnapshot;
2567 : }
2568 :
2569 : /*
2570 : * If this is a select query (e.g., for a 'no action' or 'restrict'
2571 : * trigger), we only need to see if there is a single row in the table,
2572 : * matching the key. Otherwise, limit = 0 - because we want the query to
2573 : * affect ALL the matching rows.
2574 : */
2575 6774 : limit = (expect_OK == SPI_OK_SELECT) ? 1 : 0;
2576 :
2577 : /* Switch to proper UID to perform check as */
2578 6774 : GetUserIdAndSecContext(&save_userid, &save_sec_context);
2579 6774 : SetUserIdAndSecContext(RelationGetForm(query_rel)->relowner,
2580 : save_sec_context | SECURITY_LOCAL_USERID_CHANGE |
2581 : SECURITY_NOFORCE_RLS);
2582 :
2583 : /* Finally we can run the query. */
2584 6774 : spi_result = SPI_execute_snapshot(qplan,
2585 : vals, nulls,
2586 : test_snapshot, crosscheck_snapshot,
2587 : false, false, limit);
2588 :
2589 : /* Restore UID and security context */
2590 6760 : SetUserIdAndSecContext(save_userid, save_sec_context);
2591 :
2592 : /* Check result */
2593 6760 : if (spi_result < 0)
2594 0 : elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
2595 :
2596 6760 : if (expect_OK >= 0 && spi_result != expect_OK)
2597 0 : ereport(ERROR,
2598 : (errcode(ERRCODE_INTERNAL_ERROR),
2599 : errmsg("referential integrity query on \"%s\" from constraint \"%s\" on \"%s\" gave unexpected result",
2600 : RelationGetRelationName(pk_rel),
2601 : NameStr(riinfo->conname),
2602 : RelationGetRelationName(fk_rel)),
2603 : errhint("This is most likely due to a rule having rewritten the query.")));
2604 :
2605 : /* XXX wouldn't it be clearer to do this part at the caller? */
2606 6760 : if (qkey->constr_queryno != RI_PLAN_CHECK_LOOKUPPK_FROM_PK &&
2607 5390 : expect_OK == SPI_OK_SELECT &&
2608 5390 : (SPI_processed == 0) == (qkey->constr_queryno == RI_PLAN_CHECK_LOOKUPPK))
2609 1064 : ri_ReportViolation(riinfo,
2610 : pk_rel, fk_rel,
2611 : newslot ? newslot : oldslot,
2612 : NULL,
2613 : qkey->constr_queryno, is_restrict, false);
2614 :
2615 5696 : return SPI_processed != 0;
2616 : }
2617 :
2618 : /*
2619 : * Extract fields from a tuple into Datum/nulls arrays
2620 : */
2621 : static void
2622 6978 : ri_ExtractValues(Relation rel, TupleTableSlot *slot,
2623 : const RI_ConstraintInfo *riinfo, bool rel_is_pk,
2624 : Datum *vals, char *nulls)
2625 : {
2626 : const int16 *attnums;
2627 : bool isnull;
2628 :
2629 6978 : if (rel_is_pk)
2630 2792 : attnums = riinfo->pk_attnums;
2631 : else
2632 4186 : attnums = riinfo->fk_attnums;
2633 :
2634 16492 : for (int i = 0; i < riinfo->nkeys; i++)
2635 : {
2636 9514 : vals[i] = slot_getattr(slot, attnums[i], &isnull);
2637 9514 : nulls[i] = isnull ? 'n' : ' ';
2638 : }
2639 6978 : }
2640 :
2641 : /*
2642 : * Produce an error report
2643 : *
2644 : * If the failed constraint was on insert/update to the FK table,
2645 : * we want the key names and values extracted from there, and the error
2646 : * message to look like 'key blah is not present in PK'.
2647 : * Otherwise, the attr names and values come from the PK table and the
2648 : * message looks like 'key blah is still referenced from FK'.
2649 : */
2650 : static void
2651 1154 : ri_ReportViolation(const RI_ConstraintInfo *riinfo,
2652 : Relation pk_rel, Relation fk_rel,
2653 : TupleTableSlot *violatorslot, TupleDesc tupdesc,
2654 : int queryno, bool is_restrict, bool partgone)
2655 : {
2656 : StringInfoData key_names;
2657 : StringInfoData key_values;
2658 : bool onfk;
2659 : const int16 *attnums;
2660 : Oid rel_oid;
2661 : AclResult aclresult;
2662 1154 : bool has_perm = true;
2663 :
2664 : /*
2665 : * Determine which relation to complain about. If tupdesc wasn't passed
2666 : * by caller, assume the violator tuple came from there.
2667 : */
2668 1154 : onfk = (queryno == RI_PLAN_CHECK_LOOKUPPK);
2669 1154 : if (onfk)
2670 : {
2671 600 : attnums = riinfo->fk_attnums;
2672 600 : rel_oid = fk_rel->rd_id;
2673 600 : if (tupdesc == NULL)
2674 544 : tupdesc = fk_rel->rd_att;
2675 : }
2676 : else
2677 : {
2678 554 : attnums = riinfo->pk_attnums;
2679 554 : rel_oid = pk_rel->rd_id;
2680 554 : if (tupdesc == NULL)
2681 520 : tupdesc = pk_rel->rd_att;
2682 : }
2683 :
2684 : /*
2685 : * Check permissions- if the user does not have access to view the data in
2686 : * any of the key columns then we don't include the errdetail() below.
2687 : *
2688 : * Check if RLS is enabled on the relation first. If so, we don't return
2689 : * any specifics to avoid leaking data.
2690 : *
2691 : * Check table-level permissions next and, failing that, column-level
2692 : * privileges.
2693 : *
2694 : * When a partition at the referenced side is being detached/dropped, we
2695 : * needn't check, since the user must be the table owner anyway.
2696 : */
2697 1154 : if (partgone)
2698 34 : has_perm = true;
2699 1120 : else if (check_enable_rls(rel_oid, InvalidOid, true) != RLS_ENABLED)
2700 : {
2701 1114 : aclresult = pg_class_aclcheck(rel_oid, GetUserId(), ACL_SELECT);
2702 1114 : if (aclresult != ACLCHECK_OK)
2703 : {
2704 : /* Try for column-level permissions */
2705 0 : for (int idx = 0; idx < riinfo->nkeys; idx++)
2706 : {
2707 0 : aclresult = pg_attribute_aclcheck(rel_oid, attnums[idx],
2708 : GetUserId(),
2709 : ACL_SELECT);
2710 :
2711 : /* No access to the key */
2712 0 : if (aclresult != ACLCHECK_OK)
2713 : {
2714 0 : has_perm = false;
2715 0 : break;
2716 : }
2717 : }
2718 : }
2719 : }
2720 : else
2721 6 : has_perm = false;
2722 :
2723 1154 : if (has_perm)
2724 : {
2725 : /* Get printable versions of the keys involved */
2726 1148 : initStringInfo(&key_names);
2727 1148 : initStringInfo(&key_values);
2728 2890 : for (int idx = 0; idx < riinfo->nkeys; idx++)
2729 : {
2730 1742 : int fnum = attnums[idx];
2731 1742 : Form_pg_attribute att = TupleDescAttr(tupdesc, fnum - 1);
2732 : char *name,
2733 : *val;
2734 : Datum datum;
2735 : bool isnull;
2736 :
2737 1742 : name = NameStr(att->attname);
2738 :
2739 1742 : datum = slot_getattr(violatorslot, fnum, &isnull);
2740 1742 : if (!isnull)
2741 : {
2742 : Oid foutoid;
2743 : bool typisvarlena;
2744 :
2745 1742 : getTypeOutputInfo(att->atttypid, &foutoid, &typisvarlena);
2746 1742 : val = OidOutputFunctionCall(foutoid, datum);
2747 : }
2748 : else
2749 0 : val = "null";
2750 :
2751 1742 : if (idx > 0)
2752 : {
2753 594 : appendStringInfoString(&key_names, ", ");
2754 594 : appendStringInfoString(&key_values, ", ");
2755 : }
2756 1742 : appendStringInfoString(&key_names, name);
2757 1742 : appendStringInfoString(&key_values, val);
2758 : }
2759 : }
2760 :
2761 1154 : if (partgone)
2762 34 : ereport(ERROR,
2763 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
2764 : errmsg("removing partition \"%s\" violates foreign key constraint \"%s\"",
2765 : RelationGetRelationName(pk_rel),
2766 : NameStr(riinfo->conname)),
2767 : errdetail("Key (%s)=(%s) is still referenced from table \"%s\".",
2768 : key_names.data, key_values.data,
2769 : RelationGetRelationName(fk_rel)),
2770 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
2771 1120 : else if (onfk)
2772 600 : ereport(ERROR,
2773 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
2774 : errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
2775 : RelationGetRelationName(fk_rel),
2776 : NameStr(riinfo->conname)),
2777 : has_perm ?
2778 : errdetail("Key (%s)=(%s) is not present in table \"%s\".",
2779 : key_names.data, key_values.data,
2780 : RelationGetRelationName(pk_rel)) :
2781 : errdetail("Key is not present in table \"%s\".",
2782 : RelationGetRelationName(pk_rel)),
2783 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
2784 520 : else if (is_restrict)
2785 90 : ereport(ERROR,
2786 : (errcode(ERRCODE_RESTRICT_VIOLATION),
2787 : errmsg("update or delete on table \"%s\" violates RESTRICT setting of foreign key constraint \"%s\" on table \"%s\"",
2788 : RelationGetRelationName(pk_rel),
2789 : NameStr(riinfo->conname),
2790 : RelationGetRelationName(fk_rel)),
2791 : has_perm ?
2792 : errdetail("Key (%s)=(%s) is referenced from table \"%s\".",
2793 : key_names.data, key_values.data,
2794 : RelationGetRelationName(fk_rel)) :
2795 : errdetail("Key is referenced from table \"%s\".",
2796 : RelationGetRelationName(fk_rel)),
2797 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
2798 : else
2799 430 : ereport(ERROR,
2800 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
2801 : errmsg("update or delete on table \"%s\" violates foreign key constraint \"%s\" on table \"%s\"",
2802 : RelationGetRelationName(pk_rel),
2803 : NameStr(riinfo->conname),
2804 : RelationGetRelationName(fk_rel)),
2805 : has_perm ?
2806 : errdetail("Key (%s)=(%s) is still referenced from table \"%s\".",
2807 : key_names.data, key_values.data,
2808 : RelationGetRelationName(fk_rel)) :
2809 : errdetail("Key is still referenced from table \"%s\".",
2810 : RelationGetRelationName(fk_rel)),
2811 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
2812 : }
2813 :
2814 :
2815 : /*
2816 : * ri_NullCheck -
2817 : *
2818 : * Determine the NULL state of all key values in a tuple
2819 : *
2820 : * Returns one of RI_KEYS_ALL_NULL, RI_KEYS_NONE_NULL or RI_KEYS_SOME_NULL.
2821 : */
2822 : static int
2823 8078 : ri_NullCheck(TupleDesc tupDesc,
2824 : TupleTableSlot *slot,
2825 : const RI_ConstraintInfo *riinfo, bool rel_is_pk)
2826 : {
2827 : const int16 *attnums;
2828 8078 : bool allnull = true;
2829 8078 : bool nonenull = true;
2830 :
2831 8078 : if (rel_is_pk)
2832 2500 : attnums = riinfo->pk_attnums;
2833 : else
2834 5578 : attnums = riinfo->fk_attnums;
2835 :
2836 18842 : for (int i = 0; i < riinfo->nkeys; i++)
2837 : {
2838 10764 : if (slot_attisnull(slot, attnums[i]))
2839 534 : nonenull = false;
2840 : else
2841 10230 : allnull = false;
2842 : }
2843 :
2844 8078 : if (allnull)
2845 258 : return RI_KEYS_ALL_NULL;
2846 :
2847 7820 : if (nonenull)
2848 7616 : return RI_KEYS_NONE_NULL;
2849 :
2850 204 : return RI_KEYS_SOME_NULL;
2851 : }
2852 :
2853 :
2854 : /*
2855 : * ri_InitHashTables -
2856 : *
2857 : * Initialize our internal hash tables.
2858 : */
2859 : static void
2860 422 : ri_InitHashTables(void)
2861 : {
2862 : HASHCTL ctl;
2863 :
2864 422 : ctl.keysize = sizeof(Oid);
2865 422 : ctl.entrysize = sizeof(RI_ConstraintInfo);
2866 422 : ri_constraint_cache = hash_create("RI constraint cache",
2867 : RI_INIT_CONSTRAINTHASHSIZE,
2868 : &ctl, HASH_ELEM | HASH_BLOBS);
2869 :
2870 : /* Arrange to flush cache on pg_constraint changes */
2871 422 : CacheRegisterSyscacheCallback(CONSTROID,
2872 : InvalidateConstraintCacheCallBack,
2873 : (Datum) 0);
2874 :
2875 422 : ctl.keysize = sizeof(RI_QueryKey);
2876 422 : ctl.entrysize = sizeof(RI_QueryHashEntry);
2877 422 : ri_query_cache = hash_create("RI query cache",
2878 : RI_INIT_QUERYHASHSIZE,
2879 : &ctl, HASH_ELEM | HASH_BLOBS);
2880 :
2881 422 : ctl.keysize = sizeof(RI_CompareKey);
2882 422 : ctl.entrysize = sizeof(RI_CompareHashEntry);
2883 422 : ri_compare_cache = hash_create("RI compare cache",
2884 : RI_INIT_QUERYHASHSIZE,
2885 : &ctl, HASH_ELEM | HASH_BLOBS);
2886 422 : }
2887 :
2888 :
2889 : /*
2890 : * ri_FetchPreparedPlan -
2891 : *
2892 : * Lookup for a query key in our private hash table of prepared
2893 : * and saved SPI execution plans. Return the plan if found or NULL.
2894 : */
2895 : static SPIPlanPtr
2896 6774 : ri_FetchPreparedPlan(RI_QueryKey *key)
2897 : {
2898 : RI_QueryHashEntry *entry;
2899 : SPIPlanPtr plan;
2900 :
2901 : /*
2902 : * On the first call initialize the hashtable
2903 : */
2904 6774 : if (!ri_query_cache)
2905 0 : ri_InitHashTables();
2906 :
2907 : /*
2908 : * Lookup for the key
2909 : */
2910 6774 : entry = (RI_QueryHashEntry *) hash_search(ri_query_cache,
2911 : key,
2912 : HASH_FIND, NULL);
2913 6774 : if (entry == NULL)
2914 3026 : return NULL;
2915 :
2916 : /*
2917 : * Check whether the plan is still valid. If it isn't, we don't want to
2918 : * simply rely on plancache.c to regenerate it; rather we should start
2919 : * from scratch and rebuild the query text too. This is to cover cases
2920 : * such as table/column renames. We depend on the plancache machinery to
2921 : * detect possible invalidations, though.
2922 : *
2923 : * CAUTION: this check is only trustworthy if the caller has already
2924 : * locked both FK and PK rels.
2925 : */
2926 3748 : plan = entry->plan;
2927 3748 : if (plan && SPI_plan_is_valid(plan))
2928 3386 : return plan;
2929 :
2930 : /*
2931 : * Otherwise we might as well flush the cached plan now, to free a little
2932 : * memory space before we make a new one.
2933 : */
2934 362 : entry->plan = NULL;
2935 362 : if (plan)
2936 362 : SPI_freeplan(plan);
2937 :
2938 362 : return NULL;
2939 : }
2940 :
2941 :
2942 : /*
2943 : * ri_HashPreparedPlan -
2944 : *
2945 : * Add another plan to our private SPI query plan hashtable.
2946 : */
2947 : static void
2948 3388 : ri_HashPreparedPlan(RI_QueryKey *key, SPIPlanPtr plan)
2949 : {
2950 : RI_QueryHashEntry *entry;
2951 : bool found;
2952 :
2953 : /*
2954 : * On the first call initialize the hashtable
2955 : */
2956 3388 : if (!ri_query_cache)
2957 0 : ri_InitHashTables();
2958 :
2959 : /*
2960 : * Add the new plan. We might be overwriting an entry previously found
2961 : * invalid by ri_FetchPreparedPlan.
2962 : */
2963 3388 : entry = (RI_QueryHashEntry *) hash_search(ri_query_cache,
2964 : key,
2965 : HASH_ENTER, &found);
2966 : Assert(!found || entry->plan == NULL);
2967 3388 : entry->plan = plan;
2968 3388 : }
2969 :
2970 :
2971 : /*
2972 : * ri_KeysEqual -
2973 : *
2974 : * Check if all key values in OLD and NEW are "equivalent":
2975 : * For normal FKs we check for equality.
2976 : * For temporal FKs we check that the PK side is a superset of its old value,
2977 : * or the FK side is a subset of its old value.
2978 : *
2979 : * Note: at some point we might wish to redefine this as checking for
2980 : * "IS NOT DISTINCT" rather than "=", that is, allow two nulls to be
2981 : * considered equal. Currently there is no need since all callers have
2982 : * previously found at least one of the rows to contain no nulls.
2983 : */
2984 : static bool
2985 2368 : ri_KeysEqual(Relation rel, TupleTableSlot *oldslot, TupleTableSlot *newslot,
2986 : const RI_ConstraintInfo *riinfo, bool rel_is_pk)
2987 : {
2988 : const int16 *attnums;
2989 :
2990 2368 : if (rel_is_pk)
2991 1568 : attnums = riinfo->pk_attnums;
2992 : else
2993 800 : attnums = riinfo->fk_attnums;
2994 :
2995 : /* XXX: could be worthwhile to fetch all necessary attrs at once */
2996 3788 : for (int i = 0; i < riinfo->nkeys; i++)
2997 : {
2998 : Datum oldvalue;
2999 : Datum newvalue;
3000 : bool isnull;
3001 :
3002 : /*
3003 : * Get one attribute's oldvalue. If it is NULL - they're not equal.
3004 : */
3005 2788 : oldvalue = slot_getattr(oldslot, attnums[i], &isnull);
3006 2788 : if (isnull)
3007 1368 : return false;
3008 :
3009 : /*
3010 : * Get one attribute's newvalue. If it is NULL - they're not equal.
3011 : */
3012 2758 : newvalue = slot_getattr(newslot, attnums[i], &isnull);
3013 2758 : if (isnull)
3014 0 : return false;
3015 :
3016 2758 : if (rel_is_pk)
3017 : {
3018 : /*
3019 : * If we are looking at the PK table, then do a bytewise
3020 : * comparison. We must propagate PK changes if the value is
3021 : * changed to one that "looks" different but would compare as
3022 : * equal using the equality operator. This only makes a
3023 : * difference for ON UPDATE CASCADE, but for consistency we treat
3024 : * all changes to the PK the same.
3025 : */
3026 1904 : CompactAttribute *att = TupleDescCompactAttr(oldslot->tts_tupleDescriptor, attnums[i] - 1);
3027 :
3028 1904 : if (!datum_image_eq(oldvalue, newvalue, att->attbyval, att->attlen))
3029 1032 : return false;
3030 : }
3031 : else
3032 : {
3033 : Oid eq_opr;
3034 :
3035 : /*
3036 : * When comparing the PERIOD columns we can skip the check
3037 : * whenever the referencing column stayed equal or shrank, so test
3038 : * with the contained-by operator instead.
3039 : */
3040 854 : if (riinfo->hasperiod && i == riinfo->nkeys - 1)
3041 48 : eq_opr = riinfo->period_contained_by_oper;
3042 : else
3043 806 : eq_opr = riinfo->ff_eq_oprs[i];
3044 :
3045 : /*
3046 : * For the FK table, compare with the appropriate equality
3047 : * operator. Changes that compare equal will still satisfy the
3048 : * constraint after the update.
3049 : */
3050 854 : if (!ri_CompareWithCast(eq_opr, RIAttType(rel, attnums[i]), RIAttCollation(rel, attnums[i]),
3051 : newvalue, oldvalue))
3052 306 : return false;
3053 : }
3054 : }
3055 :
3056 1000 : return true;
3057 : }
3058 :
3059 :
3060 : /*
3061 : * ri_CompareWithCast -
3062 : *
3063 : * Call the appropriate comparison operator for two values.
3064 : * Normally this is equality, but for the PERIOD part of foreign keys
3065 : * it is ContainedBy, so the order of lhs vs rhs is significant.
3066 : * See below for how the collation is applied.
3067 : *
3068 : * NB: we have already checked that neither value is null.
3069 : */
3070 : static bool
3071 854 : ri_CompareWithCast(Oid eq_opr, Oid typeid, Oid collid,
3072 : Datum lhs, Datum rhs)
3073 : {
3074 854 : RI_CompareHashEntry *entry = ri_HashCompareOp(eq_opr, typeid);
3075 :
3076 : /* Do we need to cast the values? */
3077 854 : if (OidIsValid(entry->cast_func_finfo.fn_oid))
3078 : {
3079 12 : lhs = FunctionCall3(&entry->cast_func_finfo,
3080 : lhs,
3081 : Int32GetDatum(-1), /* typmod */
3082 : BoolGetDatum(false)); /* implicit coercion */
3083 12 : rhs = FunctionCall3(&entry->cast_func_finfo,
3084 : rhs,
3085 : Int32GetDatum(-1), /* typmod */
3086 : BoolGetDatum(false)); /* implicit coercion */
3087 : }
3088 :
3089 : /*
3090 : * Apply the comparison operator.
3091 : *
3092 : * Note: This function is part of a call stack that determines whether an
3093 : * update to a row is significant enough that it needs checking or action
3094 : * on the other side of a foreign-key constraint. Therefore, the
3095 : * comparison here would need to be done with the collation of the *other*
3096 : * table. For simplicity (e.g., we might not even have the other table
3097 : * open), we'll use our own collation. This is fine because we require
3098 : * that both collations have the same notion of equality (either they are
3099 : * both deterministic or else they are both the same).
3100 : *
3101 : * With range/multirangetypes, the collation of the base type is stored as
3102 : * part of the rangetype (pg_range.rngcollation), and always used, so
3103 : * there is no danger of inconsistency even using a non-equals operator.
3104 : * But if we support arbitrary types with PERIOD, we should perhaps just
3105 : * always force a re-check.
3106 : */
3107 854 : return DatumGetBool(FunctionCall2Coll(&entry->eq_opr_finfo, collid, lhs, rhs));
3108 : }
3109 :
3110 : /*
3111 : * ri_HashCompareOp -
3112 : *
3113 : * See if we know how to compare two values, and create a new hash entry
3114 : * if not.
3115 : */
3116 : static RI_CompareHashEntry *
3117 854 : ri_HashCompareOp(Oid eq_opr, Oid typeid)
3118 : {
3119 : RI_CompareKey key;
3120 : RI_CompareHashEntry *entry;
3121 : bool found;
3122 :
3123 : /*
3124 : * On the first call initialize the hashtable
3125 : */
3126 854 : if (!ri_compare_cache)
3127 0 : ri_InitHashTables();
3128 :
3129 : /*
3130 : * Find or create a hash entry. Note we're assuming RI_CompareKey
3131 : * contains no struct padding.
3132 : */
3133 854 : key.eq_opr = eq_opr;
3134 854 : key.typeid = typeid;
3135 854 : entry = (RI_CompareHashEntry *) hash_search(ri_compare_cache,
3136 : &key,
3137 : HASH_ENTER, &found);
3138 854 : if (!found)
3139 292 : entry->valid = false;
3140 :
3141 : /*
3142 : * If not already initialized, do so. Since we'll keep this hash entry
3143 : * for the life of the backend, put any subsidiary info for the function
3144 : * cache structs into TopMemoryContext.
3145 : */
3146 854 : if (!entry->valid)
3147 : {
3148 : Oid lefttype,
3149 : righttype,
3150 : castfunc;
3151 : CoercionPathType pathtype;
3152 :
3153 : /* We always need to know how to call the equality operator */
3154 292 : fmgr_info_cxt(get_opcode(eq_opr), &entry->eq_opr_finfo,
3155 : TopMemoryContext);
3156 :
3157 : /*
3158 : * If we chose to use a cast from FK to PK type, we may have to apply
3159 : * the cast function to get to the operator's input type.
3160 : *
3161 : * XXX eventually it would be good to support array-coercion cases
3162 : * here and in ri_CompareWithCast(). At the moment there is no point
3163 : * because cases involving nonidentical array types will be rejected
3164 : * at constraint creation time.
3165 : *
3166 : * XXX perhaps also consider supporting CoerceViaIO? No need at the
3167 : * moment since that will never be generated for implicit coercions.
3168 : */
3169 292 : op_input_types(eq_opr, &lefttype, &righttype);
3170 : Assert(lefttype == righttype);
3171 292 : if (typeid == lefttype)
3172 268 : castfunc = InvalidOid; /* simplest case */
3173 : else
3174 : {
3175 24 : pathtype = find_coercion_pathway(lefttype, typeid,
3176 : COERCION_IMPLICIT,
3177 : &castfunc);
3178 24 : if (pathtype != COERCION_PATH_FUNC &&
3179 : pathtype != COERCION_PATH_RELABELTYPE)
3180 : {
3181 : /*
3182 : * The declared input type of the eq_opr might be a
3183 : * polymorphic type such as ANYARRAY or ANYENUM, or other
3184 : * special cases such as RECORD; find_coercion_pathway
3185 : * currently doesn't subsume these special cases.
3186 : */
3187 18 : if (!IsBinaryCoercible(typeid, lefttype))
3188 0 : elog(ERROR, "no conversion function from %s to %s",
3189 : format_type_be(typeid),
3190 : format_type_be(lefttype));
3191 : }
3192 : }
3193 292 : if (OidIsValid(castfunc))
3194 6 : fmgr_info_cxt(castfunc, &entry->cast_func_finfo,
3195 : TopMemoryContext);
3196 : else
3197 286 : entry->cast_func_finfo.fn_oid = InvalidOid;
3198 292 : entry->valid = true;
3199 : }
3200 :
3201 854 : return entry;
3202 : }
3203 :
3204 :
3205 : /*
3206 : * Given a trigger function OID, determine whether it is an RI trigger,
3207 : * and if so whether it is attached to PK or FK relation.
3208 : */
3209 : int
3210 8598 : RI_FKey_trigger_type(Oid tgfoid)
3211 : {
3212 8598 : switch (tgfoid)
3213 : {
3214 3088 : case F_RI_FKEY_CASCADE_DEL:
3215 : case F_RI_FKEY_CASCADE_UPD:
3216 : case F_RI_FKEY_RESTRICT_DEL:
3217 : case F_RI_FKEY_RESTRICT_UPD:
3218 : case F_RI_FKEY_SETNULL_DEL:
3219 : case F_RI_FKEY_SETNULL_UPD:
3220 : case F_RI_FKEY_SETDEFAULT_DEL:
3221 : case F_RI_FKEY_SETDEFAULT_UPD:
3222 : case F_RI_FKEY_NOACTION_DEL:
3223 : case F_RI_FKEY_NOACTION_UPD:
3224 3088 : return RI_TRIGGER_PK;
3225 :
3226 2714 : case F_RI_FKEY_CHECK_INS:
3227 : case F_RI_FKEY_CHECK_UPD:
3228 2714 : return RI_TRIGGER_FK;
3229 : }
3230 :
3231 2796 : return RI_TRIGGER_NONE;
3232 : }
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