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 : /* For RESTRICT, the same plan can be used for both ON DELETE and ON UPDATE triggers. */
78 : #define RI_PLAN_RESTRICT 5
79 : #define RI_PLAN_SETNULL_ONDELETE 6
80 : #define RI_PLAN_SETNULL_ONUPDATE 7
81 : #define RI_PLAN_SETDEFAULT_ONDELETE 8
82 : #define RI_PLAN_SETDEFAULT_ONUPDATE 9
83 :
84 : #define MAX_QUOTED_NAME_LEN (NAMEDATALEN*2+3)
85 : #define MAX_QUOTED_REL_NAME_LEN (MAX_QUOTED_NAME_LEN*2)
86 :
87 : #define RIAttName(rel, attnum) NameStr(*attnumAttName(rel, attnum))
88 : #define RIAttType(rel, attnum) attnumTypeId(rel, attnum)
89 : #define RIAttCollation(rel, attnum) attnumCollationId(rel, attnum)
90 :
91 : #define RI_TRIGTYPE_INSERT 1
92 : #define RI_TRIGTYPE_UPDATE 2
93 : #define RI_TRIGTYPE_DELETE 3
94 :
95 :
96 : /*
97 : * RI_ConstraintInfo
98 : *
99 : * Information extracted from an FK pg_constraint entry. This is cached in
100 : * ri_constraint_cache.
101 : *
102 : * Note that pf/pp/ff_eq_oprs may hold the overlaps operator instead of equals
103 : * for the PERIOD part of a temporal foreign key.
104 : */
105 : typedef struct RI_ConstraintInfo
106 : {
107 : Oid constraint_id; /* OID of pg_constraint entry (hash key) */
108 : bool valid; /* successfully initialized? */
109 : Oid constraint_root_id; /* OID of topmost ancestor constraint;
110 : * same as constraint_id if not inherited */
111 : uint32 oidHashValue; /* hash value of constraint_id */
112 : uint32 rootHashValue; /* hash value of constraint_root_id */
113 : NameData conname; /* name of the FK constraint */
114 : Oid pk_relid; /* referenced relation */
115 : Oid fk_relid; /* referencing relation */
116 : char confupdtype; /* foreign key's ON UPDATE action */
117 : char confdeltype; /* foreign key's ON DELETE action */
118 : int ndelsetcols; /* number of columns referenced in ON DELETE
119 : * SET clause */
120 : int16 confdelsetcols[RI_MAX_NUMKEYS]; /* attnums of cols to set on
121 : * delete */
122 : char confmatchtype; /* foreign key's match type */
123 : bool hasperiod; /* if the foreign key uses PERIOD */
124 : int nkeys; /* number of key columns */
125 : int16 pk_attnums[RI_MAX_NUMKEYS]; /* attnums of referenced cols */
126 : int16 fk_attnums[RI_MAX_NUMKEYS]; /* attnums of referencing cols */
127 : Oid pf_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (PK = FK) */
128 : Oid pp_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (PK = PK) */
129 : Oid ff_eq_oprs[RI_MAX_NUMKEYS]; /* equality operators (FK = FK) */
130 : Oid period_contained_by_oper; /* anyrange <@ anyrange */
131 : Oid agged_period_contained_by_oper; /* fkattr <@ range_agg(pkattr) */
132 : dlist_node valid_link; /* Link in list of valid entries */
133 : } RI_ConstraintInfo;
134 :
135 : /*
136 : * RI_QueryKey
137 : *
138 : * The key identifying a prepared SPI plan in our query hashtable
139 : */
140 : typedef struct RI_QueryKey
141 : {
142 : Oid constr_id; /* OID of pg_constraint entry */
143 : int32 constr_queryno; /* query type ID, see RI_PLAN_XXX above */
144 : } RI_QueryKey;
145 :
146 : /*
147 : * RI_QueryHashEntry
148 : */
149 : typedef struct RI_QueryHashEntry
150 : {
151 : RI_QueryKey key;
152 : SPIPlanPtr plan;
153 : } RI_QueryHashEntry;
154 :
155 : /*
156 : * RI_CompareKey
157 : *
158 : * The key identifying an entry showing how to compare two values
159 : */
160 : typedef struct RI_CompareKey
161 : {
162 : Oid eq_opr; /* the equality operator to apply */
163 : Oid typeid; /* the data type to apply it to */
164 : } RI_CompareKey;
165 :
166 : /*
167 : * RI_CompareHashEntry
168 : */
169 : typedef struct RI_CompareHashEntry
170 : {
171 : RI_CompareKey key;
172 : bool valid; /* successfully initialized? */
173 : FmgrInfo eq_opr_finfo; /* call info for equality fn */
174 : FmgrInfo cast_func_finfo; /* in case we must coerce input */
175 : } RI_CompareHashEntry;
176 :
177 :
178 : /*
179 : * Local data
180 : */
181 : static HTAB *ri_constraint_cache = NULL;
182 : static HTAB *ri_query_cache = NULL;
183 : static HTAB *ri_compare_cache = NULL;
184 : static dclist_head ri_constraint_cache_valid_list;
185 :
186 :
187 : /*
188 : * Local function prototypes
189 : */
190 : static bool ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
191 : TupleTableSlot *oldslot,
192 : const RI_ConstraintInfo *riinfo);
193 : static Datum ri_restrict(TriggerData *trigdata, bool is_no_action);
194 : static Datum ri_set(TriggerData *trigdata, bool is_set_null, int tgkind);
195 : static void quoteOneName(char *buffer, const char *name);
196 : static void quoteRelationName(char *buffer, Relation rel);
197 : static void ri_GenerateQual(StringInfo buf,
198 : const char *sep,
199 : const char *leftop, Oid leftoptype,
200 : Oid opoid,
201 : const char *rightop, Oid rightoptype);
202 : static void ri_GenerateQualCollation(StringInfo buf, Oid collation);
203 : static int ri_NullCheck(TupleDesc tupDesc, TupleTableSlot *slot,
204 : const RI_ConstraintInfo *riinfo, bool rel_is_pk);
205 : static void ri_BuildQueryKey(RI_QueryKey *key,
206 : const RI_ConstraintInfo *riinfo,
207 : int32 constr_queryno);
208 : static bool ri_KeysEqual(Relation rel, TupleTableSlot *oldslot, TupleTableSlot *newslot,
209 : const RI_ConstraintInfo *riinfo, bool rel_is_pk);
210 : static bool ri_CompareWithCast(Oid eq_opr, Oid typeid, Oid collid,
211 : Datum lhs, Datum rhs);
212 :
213 : static void ri_InitHashTables(void);
214 : static void InvalidateConstraintCacheCallBack(Datum arg, int cacheid, uint32 hashvalue);
215 : static SPIPlanPtr ri_FetchPreparedPlan(RI_QueryKey *key);
216 : static void ri_HashPreparedPlan(RI_QueryKey *key, SPIPlanPtr plan);
217 : static RI_CompareHashEntry *ri_HashCompareOp(Oid eq_opr, Oid typeid);
218 :
219 : static void ri_CheckTrigger(FunctionCallInfo fcinfo, const char *funcname,
220 : int tgkind);
221 : static const RI_ConstraintInfo *ri_FetchConstraintInfo(Trigger *trigger,
222 : Relation trig_rel, bool rel_is_pk);
223 : static const RI_ConstraintInfo *ri_LoadConstraintInfo(Oid constraintOid);
224 : static Oid get_ri_constraint_root(Oid constrOid);
225 : static SPIPlanPtr ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
226 : RI_QueryKey *qkey, Relation fk_rel, Relation pk_rel);
227 : static bool ri_PerformCheck(const RI_ConstraintInfo *riinfo,
228 : RI_QueryKey *qkey, SPIPlanPtr qplan,
229 : Relation fk_rel, Relation pk_rel,
230 : TupleTableSlot *oldslot, TupleTableSlot *newslot,
231 : bool is_restrict,
232 : bool detectNewRows, int expect_OK);
233 : static void ri_ExtractValues(Relation rel, TupleTableSlot *slot,
234 : const RI_ConstraintInfo *riinfo, bool rel_is_pk,
235 : Datum *vals, char *nulls);
236 : static void ri_ReportViolation(const RI_ConstraintInfo *riinfo,
237 : Relation pk_rel, Relation fk_rel,
238 : TupleTableSlot *violatorslot, TupleDesc tupdesc,
239 : int queryno, bool is_restrict, bool partgone) pg_attribute_noreturn();
240 :
241 :
242 : /*
243 : * RI_FKey_check -
244 : *
245 : * Check foreign key existence (combined for INSERT and UPDATE).
246 : */
247 : static Datum
248 4498 : RI_FKey_check(TriggerData *trigdata)
249 : {
250 : const RI_ConstraintInfo *riinfo;
251 : Relation fk_rel;
252 : Relation pk_rel;
253 : TupleTableSlot *newslot;
254 : RI_QueryKey qkey;
255 : SPIPlanPtr qplan;
256 :
257 4498 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
258 : trigdata->tg_relation, false);
259 :
260 4498 : if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
261 448 : newslot = trigdata->tg_newslot;
262 : else
263 4050 : newslot = trigdata->tg_trigslot;
264 :
265 : /*
266 : * We should not even consider checking the row if it is no longer valid,
267 : * since it was either deleted (so the deferred check should be skipped)
268 : * or updated (in which case only the latest version of the row should be
269 : * checked). Test its liveness according to SnapshotSelf. We need pin
270 : * and lock on the buffer to call HeapTupleSatisfiesVisibility. Caller
271 : * should be holding pin, but not lock.
272 : */
273 4498 : if (!table_tuple_satisfies_snapshot(trigdata->tg_relation, newslot, SnapshotSelf))
274 60 : return PointerGetDatum(NULL);
275 :
276 : /*
277 : * Get the relation descriptors of the FK and PK tables.
278 : *
279 : * pk_rel is opened in RowShareLock mode since that's what our eventual
280 : * SELECT FOR KEY SHARE will get on it.
281 : */
282 4438 : fk_rel = trigdata->tg_relation;
283 4438 : pk_rel = table_open(riinfo->pk_relid, RowShareLock);
284 :
285 4438 : switch (ri_NullCheck(RelationGetDescr(fk_rel), newslot, riinfo, false))
286 : {
287 132 : case RI_KEYS_ALL_NULL:
288 :
289 : /*
290 : * No further check needed - an all-NULL key passes every type of
291 : * foreign key constraint.
292 : */
293 132 : table_close(pk_rel, RowShareLock);
294 132 : return PointerGetDatum(NULL);
295 :
296 156 : case RI_KEYS_SOME_NULL:
297 :
298 : /*
299 : * This is the only case that differs between the three kinds of
300 : * MATCH.
301 : */
302 156 : switch (riinfo->confmatchtype)
303 : {
304 36 : case FKCONSTR_MATCH_FULL:
305 :
306 : /*
307 : * Not allowed - MATCH FULL says either all or none of the
308 : * attributes can be NULLs
309 : */
310 36 : ereport(ERROR,
311 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
312 : errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
313 : RelationGetRelationName(fk_rel),
314 : NameStr(riinfo->conname)),
315 : errdetail("MATCH FULL does not allow mixing of null and nonnull key values."),
316 : errtableconstraint(fk_rel,
317 : NameStr(riinfo->conname))));
318 : table_close(pk_rel, RowShareLock);
319 : return PointerGetDatum(NULL);
320 :
321 120 : case FKCONSTR_MATCH_SIMPLE:
322 :
323 : /*
324 : * MATCH SIMPLE - if ANY column is null, the key passes
325 : * the constraint.
326 : */
327 120 : table_close(pk_rel, RowShareLock);
328 120 : return PointerGetDatum(NULL);
329 :
330 : #ifdef NOT_USED
331 : case FKCONSTR_MATCH_PARTIAL:
332 :
333 : /*
334 : * MATCH PARTIAL - all non-null columns must match. (not
335 : * implemented, can be done by modifying the query below
336 : * to only include non-null columns, or by writing a
337 : * special version here)
338 : */
339 : break;
340 : #endif
341 : }
342 :
343 : case RI_KEYS_NONE_NULL:
344 :
345 : /*
346 : * Have a full qualified key - continue below for all three kinds
347 : * of MATCH.
348 : */
349 4150 : break;
350 : }
351 :
352 4150 : SPI_connect();
353 :
354 : /* Fetch or prepare a saved plan for the real check */
355 4150 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CHECK_LOOKUPPK);
356 :
357 4150 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
358 : {
359 : StringInfoData querybuf;
360 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
361 : char attname[MAX_QUOTED_NAME_LEN];
362 : char paramname[16];
363 : const char *querysep;
364 : Oid queryoids[RI_MAX_NUMKEYS];
365 : const char *pk_only;
366 :
367 : /* ----------
368 : * The query string built is
369 : * SELECT 1 FROM [ONLY] <pktable> x WHERE pkatt1 = $1 [AND ...]
370 : * FOR KEY SHARE OF x
371 : * The type id's for the $ parameters are those of the
372 : * corresponding FK attributes.
373 : *
374 : * But for temporal FKs we need to make sure
375 : * the FK's range is completely covered.
376 : * So we use this query instead:
377 : * SELECT 1
378 : * FROM (
379 : * SELECT pkperiodatt AS r
380 : * FROM [ONLY] pktable x
381 : * WHERE pkatt1 = $1 [AND ...]
382 : * AND pkperiodatt && $n
383 : * FOR KEY SHARE OF x
384 : * ) x1
385 : * HAVING $n <@ range_agg(x1.r)
386 : * Note if FOR KEY SHARE ever allows GROUP BY and HAVING
387 : * we can make this a bit simpler.
388 : * ----------
389 : */
390 2196 : initStringInfo(&querybuf);
391 4392 : pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
392 2196 : "" : "ONLY ";
393 2196 : quoteRelationName(pkrelname, pk_rel);
394 2196 : if (riinfo->hasperiod)
395 : {
396 128 : quoteOneName(attname,
397 128 : RIAttName(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]));
398 :
399 128 : appendStringInfo(&querybuf,
400 : "SELECT 1 FROM (SELECT %s AS r FROM %s%s x",
401 : attname, pk_only, pkrelname);
402 : }
403 : else
404 : {
405 2068 : appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
406 : pk_only, pkrelname);
407 : }
408 2196 : querysep = "WHERE";
409 4762 : for (int i = 0; i < riinfo->nkeys; i++)
410 : {
411 2566 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
412 2566 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
413 :
414 2566 : quoteOneName(attname,
415 2566 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
416 2566 : sprintf(paramname, "$%d", i + 1);
417 2566 : ri_GenerateQual(&querybuf, querysep,
418 : attname, pk_type,
419 : riinfo->pf_eq_oprs[i],
420 : paramname, fk_type);
421 2566 : querysep = "AND";
422 2566 : queryoids[i] = fk_type;
423 : }
424 2196 : appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
425 2196 : if (riinfo->hasperiod)
426 : {
427 128 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]);
428 :
429 128 : appendStringInfo(&querybuf, ") x1 HAVING ");
430 128 : sprintf(paramname, "$%d", riinfo->nkeys);
431 128 : ri_GenerateQual(&querybuf, "",
432 : paramname, fk_type,
433 : riinfo->agged_period_contained_by_oper,
434 : "pg_catalog.range_agg", ANYMULTIRANGEOID);
435 128 : appendStringInfo(&querybuf, "(x1.r)");
436 : }
437 :
438 : /* Prepare and save the plan */
439 2196 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
440 : &qkey, fk_rel, pk_rel);
441 : }
442 :
443 : /*
444 : * Now check that foreign key exists in PK table
445 : *
446 : * XXX detectNewRows must be true when a partitioned table is on the
447 : * referenced side. The reason is that our snapshot must be fresh in
448 : * order for the hack in find_inheritance_children() to work.
449 : */
450 4150 : ri_PerformCheck(riinfo, &qkey, qplan,
451 : fk_rel, pk_rel,
452 : NULL, newslot,
453 : false,
454 4150 : pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE,
455 : SPI_OK_SELECT);
456 :
457 3596 : if (SPI_finish() != SPI_OK_FINISH)
458 0 : elog(ERROR, "SPI_finish failed");
459 :
460 3596 : table_close(pk_rel, RowShareLock);
461 :
462 3596 : return PointerGetDatum(NULL);
463 : }
464 :
465 :
466 : /*
467 : * RI_FKey_check_ins -
468 : *
469 : * Check foreign key existence at insert event on FK table.
470 : */
471 : Datum
472 4050 : RI_FKey_check_ins(PG_FUNCTION_ARGS)
473 : {
474 : /* Check that this is a valid trigger call on the right time and event. */
475 4050 : ri_CheckTrigger(fcinfo, "RI_FKey_check_ins", RI_TRIGTYPE_INSERT);
476 :
477 : /* Share code with UPDATE case. */
478 4050 : return RI_FKey_check((TriggerData *) fcinfo->context);
479 : }
480 :
481 :
482 : /*
483 : * RI_FKey_check_upd -
484 : *
485 : * Check foreign key existence at update event on FK table.
486 : */
487 : Datum
488 448 : RI_FKey_check_upd(PG_FUNCTION_ARGS)
489 : {
490 : /* Check that this is a valid trigger call on the right time and event. */
491 448 : ri_CheckTrigger(fcinfo, "RI_FKey_check_upd", RI_TRIGTYPE_UPDATE);
492 :
493 : /* Share code with INSERT case. */
494 448 : return RI_FKey_check((TriggerData *) fcinfo->context);
495 : }
496 :
497 :
498 : /*
499 : * ri_Check_Pk_Match
500 : *
501 : * Check to see if another PK row has been created that provides the same
502 : * key values as the "oldslot" that's been modified or deleted in our trigger
503 : * event. Returns true if a match is found in the PK table.
504 : *
505 : * We assume the caller checked that the oldslot contains no NULL key values,
506 : * since otherwise a match is impossible.
507 : */
508 : static bool
509 1038 : ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
510 : TupleTableSlot *oldslot,
511 : const RI_ConstraintInfo *riinfo)
512 : {
513 : SPIPlanPtr qplan;
514 : RI_QueryKey qkey;
515 : bool result;
516 :
517 : /* Only called for non-null rows */
518 : Assert(ri_NullCheck(RelationGetDescr(pk_rel), oldslot, riinfo, true) == RI_KEYS_NONE_NULL);
519 :
520 1038 : SPI_connect();
521 :
522 : /*
523 : * Fetch or prepare a saved plan for checking PK table with values coming
524 : * from a PK row
525 : */
526 1038 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CHECK_LOOKUPPK_FROM_PK);
527 :
528 1038 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
529 : {
530 : StringInfoData querybuf;
531 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
532 : char attname[MAX_QUOTED_NAME_LEN];
533 : char paramname[16];
534 : const char *querysep;
535 : const char *pk_only;
536 : Oid queryoids[RI_MAX_NUMKEYS];
537 :
538 : /* ----------
539 : * The query string built is
540 : * SELECT 1 FROM [ONLY] <pktable> x WHERE pkatt1 = $1 [AND ...]
541 : * FOR KEY SHARE OF x
542 : * The type id's for the $ parameters are those of the
543 : * PK attributes themselves.
544 : *
545 : * But for temporal FKs we need to make sure
546 : * the old PK's range is completely covered.
547 : * So we use this query instead:
548 : * SELECT 1
549 : * FROM (
550 : * SELECT pkperiodatt AS r
551 : * FROM [ONLY] pktable x
552 : * WHERE pkatt1 = $1 [AND ...]
553 : * AND pkperiodatt && $n
554 : * FOR KEY SHARE OF x
555 : * ) x1
556 : * HAVING $n <@ range_agg(x1.r)
557 : * Note if FOR KEY SHARE ever allows GROUP BY and HAVING
558 : * we can make this a bit simpler.
559 : * ----------
560 : */
561 468 : initStringInfo(&querybuf);
562 936 : pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
563 468 : "" : "ONLY ";
564 468 : quoteRelationName(pkrelname, pk_rel);
565 468 : if (riinfo->hasperiod)
566 : {
567 128 : quoteOneName(attname, RIAttName(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]));
568 :
569 128 : appendStringInfo(&querybuf,
570 : "SELECT 1 FROM (SELECT %s AS r FROM %s%s x",
571 : attname, pk_only, pkrelname);
572 : }
573 : else
574 : {
575 340 : appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
576 : pk_only, pkrelname);
577 : }
578 468 : querysep = "WHERE";
579 1174 : for (int i = 0; i < riinfo->nkeys; i++)
580 : {
581 706 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
582 :
583 706 : quoteOneName(attname,
584 706 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
585 706 : sprintf(paramname, "$%d", i + 1);
586 706 : ri_GenerateQual(&querybuf, querysep,
587 : attname, pk_type,
588 : riinfo->pp_eq_oprs[i],
589 : paramname, pk_type);
590 706 : querysep = "AND";
591 706 : queryoids[i] = pk_type;
592 : }
593 468 : appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
594 468 : if (riinfo->hasperiod)
595 : {
596 128 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]);
597 :
598 128 : appendStringInfo(&querybuf, ") x1 HAVING ");
599 128 : sprintf(paramname, "$%d", riinfo->nkeys);
600 128 : ri_GenerateQual(&querybuf, "",
601 : paramname, fk_type,
602 : riinfo->agged_period_contained_by_oper,
603 : "pg_catalog.range_agg", ANYMULTIRANGEOID);
604 128 : appendStringInfo(&querybuf, "(x1.r)");
605 : }
606 :
607 : /* Prepare and save the plan */
608 468 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
609 : &qkey, fk_rel, pk_rel);
610 : }
611 :
612 : /*
613 : * We have a plan now. Run it.
614 : */
615 1038 : result = ri_PerformCheck(riinfo, &qkey, qplan,
616 : fk_rel, pk_rel,
617 : oldslot, NULL,
618 : false,
619 : true, /* treat like update */
620 : SPI_OK_SELECT);
621 :
622 1038 : if (SPI_finish() != SPI_OK_FINISH)
623 0 : elog(ERROR, "SPI_finish failed");
624 :
625 1038 : return result;
626 : }
627 :
628 :
629 : /*
630 : * RI_FKey_noaction_del -
631 : *
632 : * Give an error and roll back the current transaction if the
633 : * delete has resulted in a violation of the given referential
634 : * integrity constraint.
635 : */
636 : Datum
637 438 : RI_FKey_noaction_del(PG_FUNCTION_ARGS)
638 : {
639 : /* Check that this is a valid trigger call on the right time and event. */
640 438 : ri_CheckTrigger(fcinfo, "RI_FKey_noaction_del", RI_TRIGTYPE_DELETE);
641 :
642 : /* Share code with RESTRICT/UPDATE cases. */
643 438 : return ri_restrict((TriggerData *) fcinfo->context, true);
644 : }
645 :
646 : /*
647 : * RI_FKey_restrict_del -
648 : *
649 : * Restrict delete from PK table to rows unreferenced by foreign key.
650 : *
651 : * The SQL standard intends that this referential action occur exactly when
652 : * the delete is performed, rather than after. This appears to be
653 : * the only difference between "NO ACTION" and "RESTRICT". In Postgres
654 : * we still implement this as an AFTER trigger, but it's non-deferrable.
655 : */
656 : Datum
657 78 : RI_FKey_restrict_del(PG_FUNCTION_ARGS)
658 : {
659 : /* Check that this is a valid trigger call on the right time and event. */
660 78 : ri_CheckTrigger(fcinfo, "RI_FKey_restrict_del", RI_TRIGTYPE_DELETE);
661 :
662 : /* Share code with NO ACTION/UPDATE cases. */
663 78 : return ri_restrict((TriggerData *) fcinfo->context, false);
664 : }
665 :
666 : /*
667 : * RI_FKey_noaction_upd -
668 : *
669 : * Give an error and roll back the current transaction if the
670 : * update has resulted in a violation of the given referential
671 : * integrity constraint.
672 : */
673 : Datum
674 468 : RI_FKey_noaction_upd(PG_FUNCTION_ARGS)
675 : {
676 : /* Check that this is a valid trigger call on the right time and event. */
677 468 : ri_CheckTrigger(fcinfo, "RI_FKey_noaction_upd", RI_TRIGTYPE_UPDATE);
678 :
679 : /* Share code with RESTRICT/DELETE cases. */
680 468 : return ri_restrict((TriggerData *) fcinfo->context, true);
681 : }
682 :
683 : /*
684 : * RI_FKey_restrict_upd -
685 : *
686 : * Restrict update of PK to rows unreferenced by foreign key.
687 : *
688 : * The SQL standard intends that this referential action occur exactly when
689 : * the update is performed, rather than after. This appears to be
690 : * the only difference between "NO ACTION" and "RESTRICT". In Postgres
691 : * we still implement this as an AFTER trigger, but it's non-deferrable.
692 : */
693 : Datum
694 96 : RI_FKey_restrict_upd(PG_FUNCTION_ARGS)
695 : {
696 : /* Check that this is a valid trigger call on the right time and event. */
697 96 : ri_CheckTrigger(fcinfo, "RI_FKey_restrict_upd", RI_TRIGTYPE_UPDATE);
698 :
699 : /* Share code with NO ACTION/DELETE cases. */
700 96 : return ri_restrict((TriggerData *) fcinfo->context, false);
701 : }
702 :
703 : /*
704 : * ri_restrict -
705 : *
706 : * Common code for ON DELETE RESTRICT, ON DELETE NO ACTION,
707 : * ON UPDATE RESTRICT, and ON UPDATE NO ACTION.
708 : */
709 : static Datum
710 1212 : ri_restrict(TriggerData *trigdata, bool is_no_action)
711 : {
712 : const RI_ConstraintInfo *riinfo;
713 : Relation fk_rel;
714 : Relation pk_rel;
715 : TupleTableSlot *oldslot;
716 : RI_QueryKey qkey;
717 : SPIPlanPtr qplan;
718 :
719 1212 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
720 : trigdata->tg_relation, true);
721 :
722 : /*
723 : * Get the relation descriptors of the FK and PK tables and the old tuple.
724 : *
725 : * fk_rel is opened in RowShareLock mode since that's what our eventual
726 : * SELECT FOR KEY SHARE will get on it.
727 : */
728 1212 : fk_rel = table_open(riinfo->fk_relid, RowShareLock);
729 1212 : pk_rel = trigdata->tg_relation;
730 1212 : oldslot = trigdata->tg_trigslot;
731 :
732 : /*
733 : * If another PK row now exists providing the old key values, we should
734 : * not do anything. However, this check should only be made in the NO
735 : * ACTION case; in RESTRICT cases we don't wish to allow another row to be
736 : * substituted.
737 : */
738 2250 : if (is_no_action &&
739 1038 : ri_Check_Pk_Match(pk_rel, fk_rel, oldslot, riinfo))
740 : {
741 82 : table_close(fk_rel, RowShareLock);
742 82 : return PointerGetDatum(NULL);
743 : }
744 :
745 1130 : SPI_connect();
746 :
747 : /*
748 : * Fetch or prepare a saved plan for the restrict lookup (it's the same
749 : * query for delete and update cases)
750 : */
751 1130 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_RESTRICT);
752 :
753 1130 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
754 : {
755 : StringInfoData querybuf;
756 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
757 : char attname[MAX_QUOTED_NAME_LEN];
758 : char paramname[16];
759 : const char *querysep;
760 : Oid queryoids[RI_MAX_NUMKEYS];
761 : const char *fk_only;
762 :
763 : /* ----------
764 : * The query string built is
765 : * SELECT 1 FROM [ONLY] <fktable> x WHERE $1 = fkatt1 [AND ...]
766 : * FOR KEY SHARE OF x
767 : * The type id's for the $ parameters are those of the
768 : * corresponding PK attributes.
769 : * ----------
770 : */
771 468 : initStringInfo(&querybuf);
772 936 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
773 468 : "" : "ONLY ";
774 468 : quoteRelationName(fkrelname, fk_rel);
775 468 : appendStringInfo(&querybuf, "SELECT 1 FROM %s%s x",
776 : fk_only, fkrelname);
777 468 : querysep = "WHERE";
778 1216 : for (int i = 0; i < riinfo->nkeys; i++)
779 : {
780 748 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
781 748 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
782 :
783 748 : quoteOneName(attname,
784 748 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
785 748 : sprintf(paramname, "$%d", i + 1);
786 748 : ri_GenerateQual(&querybuf, querysep,
787 : paramname, pk_type,
788 : riinfo->pf_eq_oprs[i],
789 : attname, fk_type);
790 748 : querysep = "AND";
791 748 : queryoids[i] = pk_type;
792 : }
793 468 : appendStringInfoString(&querybuf, " FOR KEY SHARE OF x");
794 :
795 : /* Prepare and save the plan */
796 468 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
797 : &qkey, fk_rel, pk_rel);
798 : }
799 :
800 : /*
801 : * We have a plan now. Run it to check for existing references.
802 : */
803 1130 : ri_PerformCheck(riinfo, &qkey, qplan,
804 : fk_rel, pk_rel,
805 : oldslot, NULL,
806 1130 : !is_no_action,
807 : true, /* must detect new rows */
808 1130 : SPI_OK_SELECT);
809 :
810 634 : if (SPI_finish() != SPI_OK_FINISH)
811 0 : elog(ERROR, "SPI_finish failed");
812 :
813 634 : table_close(fk_rel, RowShareLock);
814 :
815 634 : return PointerGetDatum(NULL);
816 : }
817 :
818 :
819 : /*
820 : * RI_FKey_cascade_del -
821 : *
822 : * Cascaded delete foreign key references at delete event on PK table.
823 : */
824 : Datum
825 148 : RI_FKey_cascade_del(PG_FUNCTION_ARGS)
826 : {
827 148 : TriggerData *trigdata = (TriggerData *) fcinfo->context;
828 : const RI_ConstraintInfo *riinfo;
829 : Relation fk_rel;
830 : Relation pk_rel;
831 : TupleTableSlot *oldslot;
832 : RI_QueryKey qkey;
833 : SPIPlanPtr qplan;
834 :
835 : /* Check that this is a valid trigger call on the right time and event. */
836 148 : ri_CheckTrigger(fcinfo, "RI_FKey_cascade_del", RI_TRIGTYPE_DELETE);
837 :
838 148 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
839 : trigdata->tg_relation, true);
840 :
841 : /*
842 : * Get the relation descriptors of the FK and PK tables and the old tuple.
843 : *
844 : * fk_rel is opened in RowExclusiveLock mode since that's what our
845 : * eventual DELETE will get on it.
846 : */
847 148 : fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
848 148 : pk_rel = trigdata->tg_relation;
849 148 : oldslot = trigdata->tg_trigslot;
850 :
851 148 : SPI_connect();
852 :
853 : /* Fetch or prepare a saved plan for the cascaded delete */
854 148 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CASCADE_ONDELETE);
855 :
856 148 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
857 : {
858 : StringInfoData querybuf;
859 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
860 : char attname[MAX_QUOTED_NAME_LEN];
861 : char paramname[16];
862 : const char *querysep;
863 : Oid queryoids[RI_MAX_NUMKEYS];
864 : const char *fk_only;
865 :
866 : /* ----------
867 : * The query string built is
868 : * DELETE FROM [ONLY] <fktable> WHERE $1 = fkatt1 [AND ...]
869 : * The type id's for the $ parameters are those of the
870 : * corresponding PK attributes.
871 : * ----------
872 : */
873 92 : initStringInfo(&querybuf);
874 184 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
875 92 : "" : "ONLY ";
876 92 : quoteRelationName(fkrelname, fk_rel);
877 92 : appendStringInfo(&querybuf, "DELETE FROM %s%s",
878 : fk_only, fkrelname);
879 92 : querysep = "WHERE";
880 210 : for (int i = 0; i < riinfo->nkeys; i++)
881 : {
882 118 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
883 118 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
884 :
885 118 : quoteOneName(attname,
886 118 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
887 118 : sprintf(paramname, "$%d", i + 1);
888 118 : ri_GenerateQual(&querybuf, querysep,
889 : paramname, pk_type,
890 : riinfo->pf_eq_oprs[i],
891 : attname, fk_type);
892 118 : querysep = "AND";
893 118 : queryoids[i] = pk_type;
894 : }
895 :
896 : /* Prepare and save the plan */
897 92 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
898 : &qkey, fk_rel, pk_rel);
899 : }
900 :
901 : /*
902 : * We have a plan now. Build up the arguments from the key values in the
903 : * deleted PK tuple and delete the referencing rows
904 : */
905 148 : ri_PerformCheck(riinfo, &qkey, qplan,
906 : fk_rel, pk_rel,
907 : oldslot, NULL,
908 : false,
909 : true, /* must detect new rows */
910 : SPI_OK_DELETE);
911 :
912 146 : if (SPI_finish() != SPI_OK_FINISH)
913 0 : elog(ERROR, "SPI_finish failed");
914 :
915 146 : table_close(fk_rel, RowExclusiveLock);
916 :
917 146 : return PointerGetDatum(NULL);
918 : }
919 :
920 :
921 : /*
922 : * RI_FKey_cascade_upd -
923 : *
924 : * Cascaded update foreign key references at update event on PK table.
925 : */
926 : Datum
927 204 : RI_FKey_cascade_upd(PG_FUNCTION_ARGS)
928 : {
929 204 : TriggerData *trigdata = (TriggerData *) fcinfo->context;
930 : const RI_ConstraintInfo *riinfo;
931 : Relation fk_rel;
932 : Relation pk_rel;
933 : TupleTableSlot *newslot;
934 : TupleTableSlot *oldslot;
935 : RI_QueryKey qkey;
936 : SPIPlanPtr qplan;
937 :
938 : /* Check that this is a valid trigger call on the right time and event. */
939 204 : ri_CheckTrigger(fcinfo, "RI_FKey_cascade_upd", RI_TRIGTYPE_UPDATE);
940 :
941 204 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
942 : trigdata->tg_relation, true);
943 :
944 : /*
945 : * Get the relation descriptors of the FK and PK tables and the new and
946 : * old tuple.
947 : *
948 : * fk_rel is opened in RowExclusiveLock mode since that's what our
949 : * eventual UPDATE will get on it.
950 : */
951 204 : fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
952 204 : pk_rel = trigdata->tg_relation;
953 204 : newslot = trigdata->tg_newslot;
954 204 : oldslot = trigdata->tg_trigslot;
955 :
956 204 : SPI_connect();
957 :
958 : /* Fetch or prepare a saved plan for the cascaded update */
959 204 : ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CASCADE_ONUPDATE);
960 :
961 204 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
962 : {
963 : StringInfoData querybuf;
964 : StringInfoData qualbuf;
965 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
966 : char attname[MAX_QUOTED_NAME_LEN];
967 : char paramname[16];
968 : const char *querysep;
969 : const char *qualsep;
970 : Oid queryoids[RI_MAX_NUMKEYS * 2];
971 : const char *fk_only;
972 :
973 : /* ----------
974 : * The query string built is
975 : * UPDATE [ONLY] <fktable> SET fkatt1 = $1 [, ...]
976 : * WHERE $n = fkatt1 [AND ...]
977 : * The type id's for the $ parameters are those of the
978 : * corresponding PK attributes. Note that we are assuming
979 : * there is an assignment cast from the PK to the FK type;
980 : * else the parser will fail.
981 : * ----------
982 : */
983 116 : initStringInfo(&querybuf);
984 116 : initStringInfo(&qualbuf);
985 232 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
986 116 : "" : "ONLY ";
987 116 : quoteRelationName(fkrelname, fk_rel);
988 116 : appendStringInfo(&querybuf, "UPDATE %s%s SET",
989 : fk_only, fkrelname);
990 116 : querysep = "";
991 116 : qualsep = "WHERE";
992 260 : for (int i = 0, j = riinfo->nkeys; i < riinfo->nkeys; i++, j++)
993 : {
994 144 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
995 144 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
996 :
997 144 : quoteOneName(attname,
998 144 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
999 144 : appendStringInfo(&querybuf,
1000 : "%s %s = $%d",
1001 : querysep, attname, i + 1);
1002 144 : sprintf(paramname, "$%d", j + 1);
1003 144 : ri_GenerateQual(&qualbuf, qualsep,
1004 : paramname, pk_type,
1005 : riinfo->pf_eq_oprs[i],
1006 : attname, fk_type);
1007 144 : querysep = ",";
1008 144 : qualsep = "AND";
1009 144 : queryoids[i] = pk_type;
1010 144 : queryoids[j] = pk_type;
1011 : }
1012 116 : appendBinaryStringInfo(&querybuf, qualbuf.data, qualbuf.len);
1013 :
1014 : /* Prepare and save the plan */
1015 116 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys * 2, queryoids,
1016 : &qkey, fk_rel, pk_rel);
1017 : }
1018 :
1019 : /*
1020 : * We have a plan now. Run it to update the existing references.
1021 : */
1022 204 : ri_PerformCheck(riinfo, &qkey, qplan,
1023 : fk_rel, pk_rel,
1024 : oldslot, newslot,
1025 : false,
1026 : true, /* must detect new rows */
1027 : SPI_OK_UPDATE);
1028 :
1029 204 : if (SPI_finish() != SPI_OK_FINISH)
1030 0 : elog(ERROR, "SPI_finish failed");
1031 :
1032 204 : table_close(fk_rel, RowExclusiveLock);
1033 :
1034 204 : return PointerGetDatum(NULL);
1035 : }
1036 :
1037 :
1038 : /*
1039 : * RI_FKey_setnull_del -
1040 : *
1041 : * Set foreign key references to NULL values at delete event on PK table.
1042 : */
1043 : Datum
1044 98 : RI_FKey_setnull_del(PG_FUNCTION_ARGS)
1045 : {
1046 : /* Check that this is a valid trigger call on the right time and event. */
1047 98 : ri_CheckTrigger(fcinfo, "RI_FKey_setnull_del", RI_TRIGTYPE_DELETE);
1048 :
1049 : /* Share code with UPDATE case */
1050 98 : return ri_set((TriggerData *) fcinfo->context, true, RI_TRIGTYPE_DELETE);
1051 : }
1052 :
1053 : /*
1054 : * RI_FKey_setnull_upd -
1055 : *
1056 : * Set foreign key references to NULL at update event on PK table.
1057 : */
1058 : Datum
1059 30 : RI_FKey_setnull_upd(PG_FUNCTION_ARGS)
1060 : {
1061 : /* Check that this is a valid trigger call on the right time and event. */
1062 30 : ri_CheckTrigger(fcinfo, "RI_FKey_setnull_upd", RI_TRIGTYPE_UPDATE);
1063 :
1064 : /* Share code with DELETE case */
1065 30 : return ri_set((TriggerData *) fcinfo->context, true, RI_TRIGTYPE_UPDATE);
1066 : }
1067 :
1068 : /*
1069 : * RI_FKey_setdefault_del -
1070 : *
1071 : * Set foreign key references to defaults at delete event on PK table.
1072 : */
1073 : Datum
1074 84 : RI_FKey_setdefault_del(PG_FUNCTION_ARGS)
1075 : {
1076 : /* Check that this is a valid trigger call on the right time and event. */
1077 84 : ri_CheckTrigger(fcinfo, "RI_FKey_setdefault_del", RI_TRIGTYPE_DELETE);
1078 :
1079 : /* Share code with UPDATE case */
1080 84 : return ri_set((TriggerData *) fcinfo->context, false, RI_TRIGTYPE_DELETE);
1081 : }
1082 :
1083 : /*
1084 : * RI_FKey_setdefault_upd -
1085 : *
1086 : * Set foreign key references to defaults at update event on PK table.
1087 : */
1088 : Datum
1089 48 : RI_FKey_setdefault_upd(PG_FUNCTION_ARGS)
1090 : {
1091 : /* Check that this is a valid trigger call on the right time and event. */
1092 48 : ri_CheckTrigger(fcinfo, "RI_FKey_setdefault_upd", RI_TRIGTYPE_UPDATE);
1093 :
1094 : /* Share code with DELETE case */
1095 48 : return ri_set((TriggerData *) fcinfo->context, false, RI_TRIGTYPE_UPDATE);
1096 : }
1097 :
1098 : /*
1099 : * ri_set -
1100 : *
1101 : * Common code for ON DELETE SET NULL, ON DELETE SET DEFAULT, ON UPDATE SET
1102 : * NULL, and ON UPDATE SET DEFAULT.
1103 : */
1104 : static Datum
1105 260 : ri_set(TriggerData *trigdata, bool is_set_null, int tgkind)
1106 : {
1107 : const RI_ConstraintInfo *riinfo;
1108 : Relation fk_rel;
1109 : Relation pk_rel;
1110 : TupleTableSlot *oldslot;
1111 : RI_QueryKey qkey;
1112 : SPIPlanPtr qplan;
1113 : int32 queryno;
1114 :
1115 260 : riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
1116 : trigdata->tg_relation, true);
1117 :
1118 : /*
1119 : * Get the relation descriptors of the FK and PK tables and the old tuple.
1120 : *
1121 : * fk_rel is opened in RowExclusiveLock mode since that's what our
1122 : * eventual UPDATE will get on it.
1123 : */
1124 260 : fk_rel = table_open(riinfo->fk_relid, RowExclusiveLock);
1125 260 : pk_rel = trigdata->tg_relation;
1126 260 : oldslot = trigdata->tg_trigslot;
1127 :
1128 260 : SPI_connect();
1129 :
1130 : /*
1131 : * Fetch or prepare a saved plan for the trigger.
1132 : */
1133 260 : switch (tgkind)
1134 : {
1135 78 : case RI_TRIGTYPE_UPDATE:
1136 78 : queryno = is_set_null
1137 : ? RI_PLAN_SETNULL_ONUPDATE
1138 78 : : RI_PLAN_SETDEFAULT_ONUPDATE;
1139 78 : break;
1140 182 : case RI_TRIGTYPE_DELETE:
1141 182 : queryno = is_set_null
1142 : ? RI_PLAN_SETNULL_ONDELETE
1143 182 : : RI_PLAN_SETDEFAULT_ONDELETE;
1144 182 : break;
1145 0 : default:
1146 0 : elog(ERROR, "invalid tgkind passed to ri_set");
1147 : }
1148 :
1149 260 : ri_BuildQueryKey(&qkey, riinfo, queryno);
1150 :
1151 260 : if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
1152 : {
1153 : StringInfoData querybuf;
1154 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1155 : char attname[MAX_QUOTED_NAME_LEN];
1156 : char paramname[16];
1157 : const char *querysep;
1158 : const char *qualsep;
1159 : Oid queryoids[RI_MAX_NUMKEYS];
1160 : const char *fk_only;
1161 : int num_cols_to_set;
1162 : const int16 *set_cols;
1163 :
1164 154 : switch (tgkind)
1165 : {
1166 48 : case RI_TRIGTYPE_UPDATE:
1167 48 : num_cols_to_set = riinfo->nkeys;
1168 48 : set_cols = riinfo->fk_attnums;
1169 48 : break;
1170 106 : case RI_TRIGTYPE_DELETE:
1171 :
1172 : /*
1173 : * If confdelsetcols are present, then we only update the
1174 : * columns specified in that array, otherwise we update all
1175 : * the referencing columns.
1176 : */
1177 106 : if (riinfo->ndelsetcols != 0)
1178 : {
1179 28 : num_cols_to_set = riinfo->ndelsetcols;
1180 28 : set_cols = riinfo->confdelsetcols;
1181 : }
1182 : else
1183 : {
1184 78 : num_cols_to_set = riinfo->nkeys;
1185 78 : set_cols = riinfo->fk_attnums;
1186 : }
1187 106 : break;
1188 0 : default:
1189 0 : elog(ERROR, "invalid tgkind passed to ri_set");
1190 : }
1191 :
1192 : /* ----------
1193 : * The query string built is
1194 : * UPDATE [ONLY] <fktable> SET fkatt1 = {NULL|DEFAULT} [, ...]
1195 : * WHERE $1 = fkatt1 [AND ...]
1196 : * The type id's for the $ parameters are those of the
1197 : * corresponding PK attributes.
1198 : * ----------
1199 : */
1200 154 : initStringInfo(&querybuf);
1201 308 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1202 154 : "" : "ONLY ";
1203 154 : quoteRelationName(fkrelname, fk_rel);
1204 154 : appendStringInfo(&querybuf, "UPDATE %s%s SET",
1205 : fk_only, fkrelname);
1206 :
1207 : /*
1208 : * Add assignment clauses
1209 : */
1210 154 : querysep = "";
1211 406 : for (int i = 0; i < num_cols_to_set; i++)
1212 : {
1213 252 : quoteOneName(attname, RIAttName(fk_rel, set_cols[i]));
1214 252 : appendStringInfo(&querybuf,
1215 : "%s %s = %s",
1216 : querysep, attname,
1217 : is_set_null ? "NULL" : "DEFAULT");
1218 252 : querysep = ",";
1219 : }
1220 :
1221 : /*
1222 : * Add WHERE clause
1223 : */
1224 154 : qualsep = "WHERE";
1225 434 : for (int i = 0; i < riinfo->nkeys; i++)
1226 : {
1227 280 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1228 280 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1229 :
1230 280 : quoteOneName(attname,
1231 280 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1232 :
1233 280 : sprintf(paramname, "$%d", i + 1);
1234 280 : ri_GenerateQual(&querybuf, qualsep,
1235 : paramname, pk_type,
1236 : riinfo->pf_eq_oprs[i],
1237 : attname, fk_type);
1238 280 : qualsep = "AND";
1239 280 : queryoids[i] = pk_type;
1240 : }
1241 :
1242 : /* Prepare and save the plan */
1243 154 : qplan = ri_PlanCheck(querybuf.data, riinfo->nkeys, queryoids,
1244 : &qkey, fk_rel, pk_rel);
1245 : }
1246 :
1247 : /*
1248 : * We have a plan now. Run it to update the existing references.
1249 : */
1250 260 : ri_PerformCheck(riinfo, &qkey, qplan,
1251 : fk_rel, pk_rel,
1252 : oldslot, NULL,
1253 : false,
1254 : true, /* must detect new rows */
1255 : SPI_OK_UPDATE);
1256 :
1257 258 : if (SPI_finish() != SPI_OK_FINISH)
1258 0 : elog(ERROR, "SPI_finish failed");
1259 :
1260 258 : table_close(fk_rel, RowExclusiveLock);
1261 :
1262 258 : if (is_set_null)
1263 126 : return PointerGetDatum(NULL);
1264 : else
1265 : {
1266 : /*
1267 : * If we just deleted or updated the PK row whose key was equal to the
1268 : * FK columns' default values, and a referencing row exists in the FK
1269 : * table, we would have updated that row to the same values it already
1270 : * had --- and RI_FKey_fk_upd_check_required would hence believe no
1271 : * check is necessary. So we need to do another lookup now and in
1272 : * case a reference still exists, abort the operation. That is
1273 : * already implemented in the NO ACTION trigger, so just run it. (This
1274 : * recheck is only needed in the SET DEFAULT case, since CASCADE would
1275 : * remove such rows in case of a DELETE operation or would change the
1276 : * FK key values in case of an UPDATE, while SET NULL is certain to
1277 : * result in rows that satisfy the FK constraint.)
1278 : */
1279 132 : return ri_restrict(trigdata, true);
1280 : }
1281 : }
1282 :
1283 :
1284 : /*
1285 : * RI_FKey_pk_upd_check_required -
1286 : *
1287 : * Check if we really need to fire the RI trigger for an update or delete to a PK
1288 : * relation. This is called by the AFTER trigger queue manager to see if
1289 : * it can skip queuing an instance of an RI trigger. Returns true if the
1290 : * trigger must be fired, false if we can prove the constraint will still
1291 : * be satisfied.
1292 : *
1293 : * newslot will be NULL if this is called for a delete.
1294 : */
1295 : bool
1296 2440 : RI_FKey_pk_upd_check_required(Trigger *trigger, Relation pk_rel,
1297 : TupleTableSlot *oldslot, TupleTableSlot *newslot)
1298 : {
1299 : const RI_ConstraintInfo *riinfo;
1300 :
1301 2440 : riinfo = ri_FetchConstraintInfo(trigger, pk_rel, true);
1302 :
1303 : /*
1304 : * If any old key value is NULL, the row could not have been referenced by
1305 : * an FK row, so no check is needed.
1306 : */
1307 2440 : if (ri_NullCheck(RelationGetDescr(pk_rel), oldslot, riinfo, true) != RI_KEYS_NONE_NULL)
1308 6 : return false;
1309 :
1310 : /* If all old and new key values are equal, no check is needed */
1311 2434 : if (newslot && ri_KeysEqual(pk_rel, oldslot, newslot, riinfo, true))
1312 536 : return false;
1313 :
1314 : /* Else we need to fire the trigger. */
1315 1898 : return true;
1316 : }
1317 :
1318 : /*
1319 : * RI_FKey_fk_upd_check_required -
1320 : *
1321 : * Check if we really need to fire the RI trigger for an update to an FK
1322 : * relation. This is called by the AFTER trigger queue manager to see if
1323 : * it can skip queuing an instance of an RI trigger. Returns true if the
1324 : * trigger must be fired, false if we can prove the constraint will still
1325 : * be satisfied.
1326 : */
1327 : bool
1328 1080 : RI_FKey_fk_upd_check_required(Trigger *trigger, Relation fk_rel,
1329 : TupleTableSlot *oldslot, TupleTableSlot *newslot)
1330 : {
1331 : const RI_ConstraintInfo *riinfo;
1332 : int ri_nullcheck;
1333 :
1334 : /*
1335 : * AfterTriggerSaveEvent() handles things such that this function is never
1336 : * called for partitioned tables.
1337 : */
1338 : Assert(fk_rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE);
1339 :
1340 1080 : riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1341 :
1342 1080 : ri_nullcheck = ri_NullCheck(RelationGetDescr(fk_rel), newslot, riinfo, false);
1343 :
1344 : /*
1345 : * If all new key values are NULL, the row satisfies the constraint, so no
1346 : * check is needed.
1347 : */
1348 1080 : if (ri_nullcheck == RI_KEYS_ALL_NULL)
1349 126 : return false;
1350 :
1351 : /*
1352 : * If some new key values are NULL, the behavior depends on the match
1353 : * type.
1354 : */
1355 954 : else if (ri_nullcheck == RI_KEYS_SOME_NULL)
1356 : {
1357 30 : switch (riinfo->confmatchtype)
1358 : {
1359 24 : case FKCONSTR_MATCH_SIMPLE:
1360 :
1361 : /*
1362 : * If any new key value is NULL, the row must satisfy the
1363 : * constraint, so no check is needed.
1364 : */
1365 24 : return false;
1366 :
1367 0 : case FKCONSTR_MATCH_PARTIAL:
1368 :
1369 : /*
1370 : * Don't know, must run full check.
1371 : */
1372 0 : break;
1373 :
1374 6 : case FKCONSTR_MATCH_FULL:
1375 :
1376 : /*
1377 : * If some new key values are NULL, the row fails the
1378 : * constraint. We must not throw error here, because the row
1379 : * might get invalidated before the constraint is to be
1380 : * checked, but we should queue the event to apply the check
1381 : * later.
1382 : */
1383 6 : return true;
1384 : }
1385 924 : }
1386 :
1387 : /*
1388 : * Continues here for no new key values are NULL, or we couldn't decide
1389 : * yet.
1390 : */
1391 :
1392 : /*
1393 : * If the original row was inserted by our own transaction, we must fire
1394 : * the trigger whether or not the keys are equal. This is because our
1395 : * UPDATE will invalidate the INSERT so that the INSERT RI trigger will
1396 : * not do anything; so we had better do the UPDATE check. (We could skip
1397 : * this if we knew the INSERT trigger already fired, but there is no easy
1398 : * way to know that.)
1399 : */
1400 924 : if (slot_is_current_xact_tuple(oldslot))
1401 124 : return true;
1402 :
1403 : /* If all old and new key values are equal, no check is needed */
1404 800 : if (ri_KeysEqual(fk_rel, oldslot, newslot, riinfo, false))
1405 464 : return false;
1406 :
1407 : /* Else we need to fire the trigger. */
1408 336 : return true;
1409 : }
1410 :
1411 : /*
1412 : * RI_Initial_Check -
1413 : *
1414 : * Check an entire table for non-matching values using a single query.
1415 : * This is not a trigger procedure, but is called during ALTER TABLE
1416 : * ADD FOREIGN KEY to validate the initial table contents.
1417 : *
1418 : * We expect that the caller has made provision to prevent any problems
1419 : * caused by concurrent actions. This could be either by locking rel and
1420 : * pkrel at ShareRowExclusiveLock or higher, or by otherwise ensuring
1421 : * that triggers implementing the checks are already active.
1422 : * Hence, we do not need to lock individual rows for the check.
1423 : *
1424 : * If the check fails because the current user doesn't have permissions
1425 : * to read both tables, return false to let our caller know that they will
1426 : * need to do something else to check the constraint.
1427 : */
1428 : bool
1429 962 : RI_Initial_Check(Trigger *trigger, Relation fk_rel, Relation pk_rel)
1430 : {
1431 : const RI_ConstraintInfo *riinfo;
1432 : StringInfoData querybuf;
1433 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
1434 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1435 : char pkattname[MAX_QUOTED_NAME_LEN + 3];
1436 : char fkattname[MAX_QUOTED_NAME_LEN + 3];
1437 : RangeTblEntry *rte;
1438 : RTEPermissionInfo *pk_perminfo;
1439 : RTEPermissionInfo *fk_perminfo;
1440 962 : List *rtes = NIL;
1441 962 : List *perminfos = NIL;
1442 : const char *sep;
1443 : const char *fk_only;
1444 : const char *pk_only;
1445 : int save_nestlevel;
1446 : char workmembuf[32];
1447 : int spi_result;
1448 : SPIPlanPtr qplan;
1449 :
1450 962 : riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1451 :
1452 : /*
1453 : * Check to make sure current user has enough permissions to do the test
1454 : * query. (If not, caller can fall back to the trigger method, which
1455 : * works because it changes user IDs on the fly.)
1456 : *
1457 : * XXX are there any other show-stopper conditions to check?
1458 : */
1459 962 : pk_perminfo = makeNode(RTEPermissionInfo);
1460 962 : pk_perminfo->relid = RelationGetRelid(pk_rel);
1461 962 : pk_perminfo->requiredPerms = ACL_SELECT;
1462 962 : perminfos = lappend(perminfos, pk_perminfo);
1463 962 : rte = makeNode(RangeTblEntry);
1464 962 : rte->rtekind = RTE_RELATION;
1465 962 : rte->relid = RelationGetRelid(pk_rel);
1466 962 : rte->relkind = pk_rel->rd_rel->relkind;
1467 962 : rte->rellockmode = AccessShareLock;
1468 962 : rte->perminfoindex = list_length(perminfos);
1469 962 : rtes = lappend(rtes, rte);
1470 :
1471 962 : fk_perminfo = makeNode(RTEPermissionInfo);
1472 962 : fk_perminfo->relid = RelationGetRelid(fk_rel);
1473 962 : fk_perminfo->requiredPerms = ACL_SELECT;
1474 962 : perminfos = lappend(perminfos, fk_perminfo);
1475 962 : rte = makeNode(RangeTblEntry);
1476 962 : rte->rtekind = RTE_RELATION;
1477 962 : rte->relid = RelationGetRelid(fk_rel);
1478 962 : rte->relkind = fk_rel->rd_rel->relkind;
1479 962 : rte->rellockmode = AccessShareLock;
1480 962 : rte->perminfoindex = list_length(perminfos);
1481 962 : rtes = lappend(rtes, rte);
1482 :
1483 2244 : for (int i = 0; i < riinfo->nkeys; i++)
1484 : {
1485 : int attno;
1486 :
1487 1282 : attno = riinfo->pk_attnums[i] - FirstLowInvalidHeapAttributeNumber;
1488 1282 : pk_perminfo->selectedCols = bms_add_member(pk_perminfo->selectedCols, attno);
1489 :
1490 1282 : attno = riinfo->fk_attnums[i] - FirstLowInvalidHeapAttributeNumber;
1491 1282 : fk_perminfo->selectedCols = bms_add_member(fk_perminfo->selectedCols, attno);
1492 : }
1493 :
1494 962 : if (!ExecCheckPermissions(rtes, perminfos, false))
1495 12 : return false;
1496 :
1497 : /*
1498 : * Also punt if RLS is enabled on either table unless this role has the
1499 : * bypassrls right or is the table owner of the table(s) involved which
1500 : * have RLS enabled.
1501 : */
1502 950 : if (!has_bypassrls_privilege(GetUserId()) &&
1503 0 : ((pk_rel->rd_rel->relrowsecurity &&
1504 0 : !object_ownercheck(RelationRelationId, RelationGetRelid(pk_rel),
1505 0 : GetUserId())) ||
1506 0 : (fk_rel->rd_rel->relrowsecurity &&
1507 0 : !object_ownercheck(RelationRelationId, RelationGetRelid(fk_rel),
1508 : GetUserId()))))
1509 0 : return false;
1510 :
1511 : /*----------
1512 : * The query string built is:
1513 : * SELECT fk.keycols FROM [ONLY] relname fk
1514 : * LEFT OUTER JOIN [ONLY] pkrelname pk
1515 : * ON (pk.pkkeycol1=fk.keycol1 [AND ...])
1516 : * WHERE pk.pkkeycol1 IS NULL AND
1517 : * For MATCH SIMPLE:
1518 : * (fk.keycol1 IS NOT NULL [AND ...])
1519 : * For MATCH FULL:
1520 : * (fk.keycol1 IS NOT NULL [OR ...])
1521 : *
1522 : * We attach COLLATE clauses to the operators when comparing columns
1523 : * that have different collations.
1524 : *----------
1525 : */
1526 950 : initStringInfo(&querybuf);
1527 950 : appendStringInfoString(&querybuf, "SELECT ");
1528 950 : sep = "";
1529 2208 : for (int i = 0; i < riinfo->nkeys; i++)
1530 : {
1531 1258 : quoteOneName(fkattname,
1532 1258 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1533 1258 : appendStringInfo(&querybuf, "%sfk.%s", sep, fkattname);
1534 1258 : sep = ", ";
1535 : }
1536 :
1537 950 : quoteRelationName(pkrelname, pk_rel);
1538 950 : quoteRelationName(fkrelname, fk_rel);
1539 1900 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1540 950 : "" : "ONLY ";
1541 1900 : pk_only = pk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1542 950 : "" : "ONLY ";
1543 950 : appendStringInfo(&querybuf,
1544 : " FROM %s%s fk LEFT OUTER JOIN %s%s pk ON",
1545 : fk_only, fkrelname, pk_only, pkrelname);
1546 :
1547 950 : strcpy(pkattname, "pk.");
1548 950 : strcpy(fkattname, "fk.");
1549 950 : sep = "(";
1550 2208 : for (int i = 0; i < riinfo->nkeys; i++)
1551 : {
1552 1258 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1553 1258 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1554 1258 : Oid pk_coll = RIAttCollation(pk_rel, riinfo->pk_attnums[i]);
1555 1258 : Oid fk_coll = RIAttCollation(fk_rel, riinfo->fk_attnums[i]);
1556 :
1557 1258 : quoteOneName(pkattname + 3,
1558 1258 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
1559 1258 : quoteOneName(fkattname + 3,
1560 1258 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1561 1258 : ri_GenerateQual(&querybuf, sep,
1562 : pkattname, pk_type,
1563 : riinfo->pf_eq_oprs[i],
1564 : fkattname, fk_type);
1565 1258 : if (pk_coll != fk_coll)
1566 12 : ri_GenerateQualCollation(&querybuf, pk_coll);
1567 1258 : sep = "AND";
1568 : }
1569 :
1570 : /*
1571 : * It's sufficient to test any one pk attribute for null to detect a join
1572 : * failure.
1573 : */
1574 950 : quoteOneName(pkattname, RIAttName(pk_rel, riinfo->pk_attnums[0]));
1575 950 : appendStringInfo(&querybuf, ") WHERE pk.%s IS NULL AND (", pkattname);
1576 :
1577 950 : sep = "";
1578 2208 : for (int i = 0; i < riinfo->nkeys; i++)
1579 : {
1580 1258 : quoteOneName(fkattname, RIAttName(fk_rel, riinfo->fk_attnums[i]));
1581 1258 : appendStringInfo(&querybuf,
1582 : "%sfk.%s IS NOT NULL",
1583 : sep, fkattname);
1584 1258 : switch (riinfo->confmatchtype)
1585 : {
1586 1158 : case FKCONSTR_MATCH_SIMPLE:
1587 1158 : sep = " AND ";
1588 1158 : break;
1589 100 : case FKCONSTR_MATCH_FULL:
1590 100 : sep = " OR ";
1591 100 : break;
1592 : }
1593 1258 : }
1594 950 : appendStringInfoChar(&querybuf, ')');
1595 :
1596 : /*
1597 : * Temporarily increase work_mem so that the check query can be executed
1598 : * more efficiently. It seems okay to do this because the query is simple
1599 : * enough to not use a multiple of work_mem, and one typically would not
1600 : * have many large foreign-key validations happening concurrently. So
1601 : * this seems to meet the criteria for being considered a "maintenance"
1602 : * operation, and accordingly we use maintenance_work_mem. However, we
1603 : * must also set hash_mem_multiplier to 1, since it is surely not okay to
1604 : * let that get applied to the maintenance_work_mem value.
1605 : *
1606 : * We use the equivalent of a function SET option to allow the setting to
1607 : * persist for exactly the duration of the check query. guc.c also takes
1608 : * care of undoing the setting on error.
1609 : */
1610 950 : save_nestlevel = NewGUCNestLevel();
1611 :
1612 950 : snprintf(workmembuf, sizeof(workmembuf), "%d", maintenance_work_mem);
1613 950 : (void) set_config_option("work_mem", workmembuf,
1614 : PGC_USERSET, PGC_S_SESSION,
1615 : GUC_ACTION_SAVE, true, 0, false);
1616 950 : (void) set_config_option("hash_mem_multiplier", "1",
1617 : PGC_USERSET, PGC_S_SESSION,
1618 : GUC_ACTION_SAVE, true, 0, false);
1619 :
1620 950 : SPI_connect();
1621 :
1622 : /*
1623 : * Generate the plan. We don't need to cache it, and there are no
1624 : * arguments to the plan.
1625 : */
1626 950 : qplan = SPI_prepare(querybuf.data, 0, NULL);
1627 :
1628 950 : if (qplan == NULL)
1629 0 : elog(ERROR, "SPI_prepare returned %s for %s",
1630 : SPI_result_code_string(SPI_result), querybuf.data);
1631 :
1632 : /*
1633 : * Run the plan. For safety we force a current snapshot to be used. (In
1634 : * transaction-snapshot mode, this arguably violates transaction isolation
1635 : * rules, but we really haven't got much choice.) We don't need to
1636 : * register the snapshot, because SPI_execute_snapshot will see to it. We
1637 : * need at most one tuple returned, so pass limit = 1.
1638 : */
1639 950 : spi_result = SPI_execute_snapshot(qplan,
1640 : NULL, NULL,
1641 : GetLatestSnapshot(),
1642 : InvalidSnapshot,
1643 : true, false, 1);
1644 :
1645 : /* Check result */
1646 950 : if (spi_result != SPI_OK_SELECT)
1647 0 : elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
1648 :
1649 : /* Did we find a tuple violating the constraint? */
1650 950 : if (SPI_processed > 0)
1651 : {
1652 : TupleTableSlot *slot;
1653 62 : HeapTuple tuple = SPI_tuptable->vals[0];
1654 62 : TupleDesc tupdesc = SPI_tuptable->tupdesc;
1655 : RI_ConstraintInfo fake_riinfo;
1656 :
1657 62 : slot = MakeSingleTupleTableSlot(tupdesc, &TTSOpsVirtual);
1658 :
1659 62 : heap_deform_tuple(tuple, tupdesc,
1660 : slot->tts_values, slot->tts_isnull);
1661 62 : ExecStoreVirtualTuple(slot);
1662 :
1663 : /*
1664 : * The columns to look at in the result tuple are 1..N, not whatever
1665 : * they are in the fk_rel. Hack up riinfo so that the subroutines
1666 : * called here will behave properly.
1667 : *
1668 : * In addition to this, we have to pass the correct tupdesc to
1669 : * ri_ReportViolation, overriding its normal habit of using the pk_rel
1670 : * or fk_rel's tupdesc.
1671 : */
1672 62 : memcpy(&fake_riinfo, riinfo, sizeof(RI_ConstraintInfo));
1673 142 : for (int i = 0; i < fake_riinfo.nkeys; i++)
1674 80 : fake_riinfo.fk_attnums[i] = i + 1;
1675 :
1676 : /*
1677 : * If it's MATCH FULL, and there are any nulls in the FK keys,
1678 : * complain about that rather than the lack of a match. MATCH FULL
1679 : * disallows partially-null FK rows.
1680 : */
1681 86 : if (fake_riinfo.confmatchtype == FKCONSTR_MATCH_FULL &&
1682 24 : ri_NullCheck(tupdesc, slot, &fake_riinfo, false) != RI_KEYS_NONE_NULL)
1683 12 : ereport(ERROR,
1684 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
1685 : errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
1686 : RelationGetRelationName(fk_rel),
1687 : NameStr(fake_riinfo.conname)),
1688 : errdetail("MATCH FULL does not allow mixing of null and nonnull key values."),
1689 : errtableconstraint(fk_rel,
1690 : NameStr(fake_riinfo.conname))));
1691 :
1692 : /*
1693 : * We tell ri_ReportViolation we were doing the RI_PLAN_CHECK_LOOKUPPK
1694 : * query, which isn't true, but will cause it to use
1695 : * fake_riinfo.fk_attnums as we need.
1696 : */
1697 50 : ri_ReportViolation(&fake_riinfo,
1698 : pk_rel, fk_rel,
1699 : slot, tupdesc,
1700 : RI_PLAN_CHECK_LOOKUPPK, false, false);
1701 :
1702 : ExecDropSingleTupleTableSlot(slot);
1703 : }
1704 :
1705 888 : if (SPI_finish() != SPI_OK_FINISH)
1706 0 : elog(ERROR, "SPI_finish failed");
1707 :
1708 : /*
1709 : * Restore work_mem and hash_mem_multiplier.
1710 : */
1711 888 : AtEOXact_GUC(true, save_nestlevel);
1712 :
1713 888 : return true;
1714 : }
1715 :
1716 : /*
1717 : * RI_PartitionRemove_Check -
1718 : *
1719 : * Verify no referencing values exist, when a partition is detached on
1720 : * the referenced side of a foreign key constraint.
1721 : */
1722 : void
1723 86 : RI_PartitionRemove_Check(Trigger *trigger, Relation fk_rel, Relation pk_rel)
1724 : {
1725 : const RI_ConstraintInfo *riinfo;
1726 : StringInfoData querybuf;
1727 : char *constraintDef;
1728 : char pkrelname[MAX_QUOTED_REL_NAME_LEN];
1729 : char fkrelname[MAX_QUOTED_REL_NAME_LEN];
1730 : char pkattname[MAX_QUOTED_NAME_LEN + 3];
1731 : char fkattname[MAX_QUOTED_NAME_LEN + 3];
1732 : const char *sep;
1733 : const char *fk_only;
1734 : int save_nestlevel;
1735 : char workmembuf[32];
1736 : int spi_result;
1737 : SPIPlanPtr qplan;
1738 : int i;
1739 :
1740 86 : riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
1741 :
1742 : /*
1743 : * We don't check permissions before displaying the error message, on the
1744 : * assumption that the user detaching the partition must have enough
1745 : * privileges to examine the table contents anyhow.
1746 : */
1747 :
1748 : /*----------
1749 : * The query string built is:
1750 : * SELECT fk.keycols FROM [ONLY] relname fk
1751 : * JOIN pkrelname pk
1752 : * ON (pk.pkkeycol1=fk.keycol1 [AND ...])
1753 : * WHERE (<partition constraint>) AND
1754 : * For MATCH SIMPLE:
1755 : * (fk.keycol1 IS NOT NULL [AND ...])
1756 : * For MATCH FULL:
1757 : * (fk.keycol1 IS NOT NULL [OR ...])
1758 : *
1759 : * We attach COLLATE clauses to the operators when comparing columns
1760 : * that have different collations.
1761 : *----------
1762 : */
1763 86 : initStringInfo(&querybuf);
1764 86 : appendStringInfoString(&querybuf, "SELECT ");
1765 86 : sep = "";
1766 172 : for (i = 0; i < riinfo->nkeys; i++)
1767 : {
1768 86 : quoteOneName(fkattname,
1769 86 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1770 86 : appendStringInfo(&querybuf, "%sfk.%s", sep, fkattname);
1771 86 : sep = ", ";
1772 : }
1773 :
1774 86 : quoteRelationName(pkrelname, pk_rel);
1775 86 : quoteRelationName(fkrelname, fk_rel);
1776 172 : fk_only = fk_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE ?
1777 86 : "" : "ONLY ";
1778 86 : appendStringInfo(&querybuf,
1779 : " FROM %s%s fk JOIN %s pk ON",
1780 : fk_only, fkrelname, pkrelname);
1781 86 : strcpy(pkattname, "pk.");
1782 86 : strcpy(fkattname, "fk.");
1783 86 : sep = "(";
1784 172 : for (i = 0; i < riinfo->nkeys; i++)
1785 : {
1786 86 : Oid pk_type = RIAttType(pk_rel, riinfo->pk_attnums[i]);
1787 86 : Oid fk_type = RIAttType(fk_rel, riinfo->fk_attnums[i]);
1788 86 : Oid pk_coll = RIAttCollation(pk_rel, riinfo->pk_attnums[i]);
1789 86 : Oid fk_coll = RIAttCollation(fk_rel, riinfo->fk_attnums[i]);
1790 :
1791 86 : quoteOneName(pkattname + 3,
1792 86 : RIAttName(pk_rel, riinfo->pk_attnums[i]));
1793 86 : quoteOneName(fkattname + 3,
1794 86 : RIAttName(fk_rel, riinfo->fk_attnums[i]));
1795 86 : ri_GenerateQual(&querybuf, sep,
1796 : pkattname, pk_type,
1797 : riinfo->pf_eq_oprs[i],
1798 : fkattname, fk_type);
1799 86 : if (pk_coll != fk_coll)
1800 0 : ri_GenerateQualCollation(&querybuf, pk_coll);
1801 86 : sep = "AND";
1802 : }
1803 :
1804 : /*
1805 : * Start the WHERE clause with the partition constraint (except if this is
1806 : * the default partition and there's no other partition, because the
1807 : * partition constraint is the empty string in that case.)
1808 : */
1809 86 : constraintDef = pg_get_partconstrdef_string(RelationGetRelid(pk_rel), "pk");
1810 86 : if (constraintDef && constraintDef[0] != '\0')
1811 86 : appendStringInfo(&querybuf, ") WHERE %s AND (",
1812 : constraintDef);
1813 : else
1814 0 : appendStringInfoString(&querybuf, ") WHERE (");
1815 :
1816 86 : sep = "";
1817 172 : for (i = 0; i < riinfo->nkeys; i++)
1818 : {
1819 86 : quoteOneName(fkattname, RIAttName(fk_rel, riinfo->fk_attnums[i]));
1820 86 : appendStringInfo(&querybuf,
1821 : "%sfk.%s IS NOT NULL",
1822 : sep, fkattname);
1823 86 : switch (riinfo->confmatchtype)
1824 : {
1825 86 : case FKCONSTR_MATCH_SIMPLE:
1826 86 : sep = " AND ";
1827 86 : break;
1828 0 : case FKCONSTR_MATCH_FULL:
1829 0 : sep = " OR ";
1830 0 : break;
1831 : }
1832 86 : }
1833 86 : appendStringInfoChar(&querybuf, ')');
1834 :
1835 : /*
1836 : * Temporarily increase work_mem so that the check query can be executed
1837 : * more efficiently. It seems okay to do this because the query is simple
1838 : * enough to not use a multiple of work_mem, and one typically would not
1839 : * have many large foreign-key validations happening concurrently. So
1840 : * this seems to meet the criteria for being considered a "maintenance"
1841 : * operation, and accordingly we use maintenance_work_mem. However, we
1842 : * must also set hash_mem_multiplier to 1, since it is surely not okay to
1843 : * let that get applied to the maintenance_work_mem value.
1844 : *
1845 : * We use the equivalent of a function SET option to allow the setting to
1846 : * persist for exactly the duration of the check query. guc.c also takes
1847 : * care of undoing the setting on error.
1848 : */
1849 86 : save_nestlevel = NewGUCNestLevel();
1850 :
1851 86 : snprintf(workmembuf, sizeof(workmembuf), "%d", maintenance_work_mem);
1852 86 : (void) set_config_option("work_mem", workmembuf,
1853 : PGC_USERSET, PGC_S_SESSION,
1854 : GUC_ACTION_SAVE, true, 0, false);
1855 86 : (void) set_config_option("hash_mem_multiplier", "1",
1856 : PGC_USERSET, PGC_S_SESSION,
1857 : GUC_ACTION_SAVE, true, 0, false);
1858 :
1859 86 : SPI_connect();
1860 :
1861 : /*
1862 : * Generate the plan. We don't need to cache it, and there are no
1863 : * arguments to the plan.
1864 : */
1865 86 : qplan = SPI_prepare(querybuf.data, 0, NULL);
1866 :
1867 86 : if (qplan == NULL)
1868 0 : elog(ERROR, "SPI_prepare returned %s for %s",
1869 : SPI_result_code_string(SPI_result), querybuf.data);
1870 :
1871 : /*
1872 : * Run the plan. For safety we force a current snapshot to be used. (In
1873 : * transaction-snapshot mode, this arguably violates transaction isolation
1874 : * rules, but we really haven't got much choice.) We don't need to
1875 : * register the snapshot, because SPI_execute_snapshot will see to it. We
1876 : * need at most one tuple returned, so pass limit = 1.
1877 : */
1878 86 : spi_result = SPI_execute_snapshot(qplan,
1879 : NULL, NULL,
1880 : GetLatestSnapshot(),
1881 : InvalidSnapshot,
1882 : true, false, 1);
1883 :
1884 : /* Check result */
1885 86 : if (spi_result != SPI_OK_SELECT)
1886 0 : elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
1887 :
1888 : /* Did we find a tuple that would violate the constraint? */
1889 86 : if (SPI_processed > 0)
1890 : {
1891 : TupleTableSlot *slot;
1892 34 : HeapTuple tuple = SPI_tuptable->vals[0];
1893 34 : TupleDesc tupdesc = SPI_tuptable->tupdesc;
1894 : RI_ConstraintInfo fake_riinfo;
1895 :
1896 34 : slot = MakeSingleTupleTableSlot(tupdesc, &TTSOpsVirtual);
1897 :
1898 34 : heap_deform_tuple(tuple, tupdesc,
1899 : slot->tts_values, slot->tts_isnull);
1900 34 : ExecStoreVirtualTuple(slot);
1901 :
1902 : /*
1903 : * The columns to look at in the result tuple are 1..N, not whatever
1904 : * they are in the fk_rel. Hack up riinfo so that ri_ReportViolation
1905 : * will behave properly.
1906 : *
1907 : * In addition to this, we have to pass the correct tupdesc to
1908 : * ri_ReportViolation, overriding its normal habit of using the pk_rel
1909 : * or fk_rel's tupdesc.
1910 : */
1911 34 : memcpy(&fake_riinfo, riinfo, sizeof(RI_ConstraintInfo));
1912 68 : for (i = 0; i < fake_riinfo.nkeys; i++)
1913 34 : fake_riinfo.pk_attnums[i] = i + 1;
1914 :
1915 34 : ri_ReportViolation(&fake_riinfo, pk_rel, fk_rel,
1916 : slot, tupdesc, 0, false, true);
1917 : }
1918 :
1919 52 : if (SPI_finish() != SPI_OK_FINISH)
1920 0 : elog(ERROR, "SPI_finish failed");
1921 :
1922 : /*
1923 : * Restore work_mem and hash_mem_multiplier.
1924 : */
1925 52 : AtEOXact_GUC(true, save_nestlevel);
1926 52 : }
1927 :
1928 :
1929 : /* ----------
1930 : * Local functions below
1931 : * ----------
1932 : */
1933 :
1934 :
1935 : /*
1936 : * quoteOneName --- safely quote a single SQL name
1937 : *
1938 : * buffer must be MAX_QUOTED_NAME_LEN long (includes room for \0)
1939 : */
1940 : static void
1941 22552 : quoteOneName(char *buffer, const char *name)
1942 : {
1943 : /* Rather than trying to be smart, just always quote it. */
1944 22552 : *buffer++ = '"';
1945 143278 : while (*name)
1946 : {
1947 120726 : if (*name == '"')
1948 0 : *buffer++ = '"';
1949 120726 : *buffer++ = *name++;
1950 : }
1951 22552 : *buffer++ = '"';
1952 22552 : *buffer = '\0';
1953 22552 : }
1954 :
1955 : /*
1956 : * quoteRelationName --- safely quote a fully qualified relation name
1957 : *
1958 : * buffer must be MAX_QUOTED_REL_NAME_LEN long (includes room for \0)
1959 : */
1960 : static void
1961 5566 : quoteRelationName(char *buffer, Relation rel)
1962 : {
1963 5566 : quoteOneName(buffer, get_namespace_name(RelationGetNamespace(rel)));
1964 5566 : buffer += strlen(buffer);
1965 5566 : *buffer++ = '.';
1966 5566 : quoteOneName(buffer, RelationGetRelationName(rel));
1967 5566 : }
1968 :
1969 : /*
1970 : * ri_GenerateQual --- generate a WHERE clause equating two variables
1971 : *
1972 : * This basically appends " sep leftop op rightop" to buf, adding casts
1973 : * and schema qualification as needed to ensure that the parser will select
1974 : * the operator we specify. leftop and rightop should be parenthesized
1975 : * if they aren't variables or parameters.
1976 : */
1977 : static void
1978 6162 : ri_GenerateQual(StringInfo buf,
1979 : const char *sep,
1980 : const char *leftop, Oid leftoptype,
1981 : Oid opoid,
1982 : const char *rightop, Oid rightoptype)
1983 : {
1984 6162 : appendStringInfo(buf, " %s ", sep);
1985 6162 : generate_operator_clause(buf, leftop, leftoptype, opoid,
1986 : rightop, rightoptype);
1987 6162 : }
1988 :
1989 : /*
1990 : * ri_GenerateQualCollation --- add a COLLATE spec to a WHERE clause
1991 : *
1992 : * We only have to use this function when directly comparing the referencing
1993 : * and referenced columns, if they are of different collations; else the
1994 : * parser will fail to resolve the collation to use. We don't need to use
1995 : * this function for RI queries that compare a variable to a $n parameter.
1996 : * Since parameter symbols always have default collation, the effect will be
1997 : * to use the variable's collation.
1998 : *
1999 : * Note that we require that the collations of the referencing and the
2000 : * referenced column have the same notion of equality: Either they have to
2001 : * both be deterministic or else they both have to be the same. (See also
2002 : * ATAddForeignKeyConstraint().)
2003 : */
2004 : static void
2005 12 : ri_GenerateQualCollation(StringInfo buf, Oid collation)
2006 : {
2007 : HeapTuple tp;
2008 : Form_pg_collation colltup;
2009 : char *collname;
2010 : char onename[MAX_QUOTED_NAME_LEN];
2011 :
2012 : /* Nothing to do if it's a noncollatable data type */
2013 12 : if (!OidIsValid(collation))
2014 0 : return;
2015 :
2016 12 : tp = SearchSysCache1(COLLOID, ObjectIdGetDatum(collation));
2017 12 : if (!HeapTupleIsValid(tp))
2018 0 : elog(ERROR, "cache lookup failed for collation %u", collation);
2019 12 : colltup = (Form_pg_collation) GETSTRUCT(tp);
2020 12 : collname = NameStr(colltup->collname);
2021 :
2022 : /*
2023 : * We qualify the name always, for simplicity and to ensure the query is
2024 : * not search-path-dependent.
2025 : */
2026 12 : quoteOneName(onename, get_namespace_name(colltup->collnamespace));
2027 12 : appendStringInfo(buf, " COLLATE %s", onename);
2028 12 : quoteOneName(onename, collname);
2029 12 : appendStringInfo(buf, ".%s", onename);
2030 :
2031 12 : ReleaseSysCache(tp);
2032 : }
2033 :
2034 : /* ----------
2035 : * ri_BuildQueryKey -
2036 : *
2037 : * Construct a hashtable key for a prepared SPI plan of an FK constraint.
2038 : *
2039 : * key: output argument, *key is filled in based on the other arguments
2040 : * riinfo: info derived from pg_constraint entry
2041 : * constr_queryno: an internal number identifying the query type
2042 : * (see RI_PLAN_XXX constants at head of file)
2043 : * ----------
2044 : */
2045 : static void
2046 6930 : ri_BuildQueryKey(RI_QueryKey *key, const RI_ConstraintInfo *riinfo,
2047 : int32 constr_queryno)
2048 : {
2049 : /*
2050 : * Inherited constraints with a common ancestor can share ri_query_cache
2051 : * entries for all query types except RI_PLAN_CHECK_LOOKUPPK_FROM_PK.
2052 : * Except in that case, the query processes the other table involved in
2053 : * the FK constraint (i.e., not the table on which the trigger has been
2054 : * fired), and so it will be the same for all members of the inheritance
2055 : * tree. So we may use the root constraint's OID in the hash key, rather
2056 : * than the constraint's own OID. This avoids creating duplicate SPI
2057 : * plans, saving lots of work and memory when there are many partitions
2058 : * with similar FK constraints.
2059 : *
2060 : * (Note that we must still have a separate RI_ConstraintInfo for each
2061 : * constraint, because partitions can have different column orders,
2062 : * resulting in different pk_attnums[] or fk_attnums[] array contents.)
2063 : *
2064 : * We assume struct RI_QueryKey contains no padding bytes, else we'd need
2065 : * to use memset to clear them.
2066 : */
2067 6930 : if (constr_queryno != RI_PLAN_CHECK_LOOKUPPK_FROM_PK)
2068 5892 : key->constr_id = riinfo->constraint_root_id;
2069 : else
2070 1038 : key->constr_id = riinfo->constraint_id;
2071 6930 : key->constr_queryno = constr_queryno;
2072 6930 : }
2073 :
2074 : /*
2075 : * Check that RI trigger function was called in expected context
2076 : */
2077 : static void
2078 6190 : ri_CheckTrigger(FunctionCallInfo fcinfo, const char *funcname, int tgkind)
2079 : {
2080 6190 : TriggerData *trigdata = (TriggerData *) fcinfo->context;
2081 :
2082 6190 : if (!CALLED_AS_TRIGGER(fcinfo))
2083 0 : ereport(ERROR,
2084 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2085 : errmsg("function \"%s\" was not called by trigger manager", funcname)));
2086 :
2087 : /*
2088 : * Check proper event
2089 : */
2090 6190 : if (!TRIGGER_FIRED_AFTER(trigdata->tg_event) ||
2091 6190 : !TRIGGER_FIRED_FOR_ROW(trigdata->tg_event))
2092 0 : ereport(ERROR,
2093 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2094 : errmsg("function \"%s\" must be fired AFTER ROW", funcname)));
2095 :
2096 6190 : switch (tgkind)
2097 : {
2098 4050 : case RI_TRIGTYPE_INSERT:
2099 4050 : if (!TRIGGER_FIRED_BY_INSERT(trigdata->tg_event))
2100 0 : ereport(ERROR,
2101 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2102 : errmsg("function \"%s\" must be fired for INSERT", funcname)));
2103 4050 : break;
2104 1294 : case RI_TRIGTYPE_UPDATE:
2105 1294 : if (!TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
2106 0 : ereport(ERROR,
2107 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2108 : errmsg("function \"%s\" must be fired for UPDATE", funcname)));
2109 1294 : break;
2110 846 : case RI_TRIGTYPE_DELETE:
2111 846 : if (!TRIGGER_FIRED_BY_DELETE(trigdata->tg_event))
2112 0 : ereport(ERROR,
2113 : (errcode(ERRCODE_E_R_I_E_TRIGGER_PROTOCOL_VIOLATED),
2114 : errmsg("function \"%s\" must be fired for DELETE", funcname)));
2115 846 : break;
2116 : }
2117 6190 : }
2118 :
2119 :
2120 : /*
2121 : * Fetch the RI_ConstraintInfo struct for the trigger's FK constraint.
2122 : */
2123 : static const RI_ConstraintInfo *
2124 10890 : ri_FetchConstraintInfo(Trigger *trigger, Relation trig_rel, bool rel_is_pk)
2125 : {
2126 10890 : Oid constraintOid = trigger->tgconstraint;
2127 : const RI_ConstraintInfo *riinfo;
2128 :
2129 : /*
2130 : * Check that the FK constraint's OID is available; it might not be if
2131 : * we've been invoked via an ordinary trigger or an old-style "constraint
2132 : * trigger".
2133 : */
2134 10890 : if (!OidIsValid(constraintOid))
2135 0 : ereport(ERROR,
2136 : (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
2137 : errmsg("no pg_constraint entry for trigger \"%s\" on table \"%s\"",
2138 : trigger->tgname, RelationGetRelationName(trig_rel)),
2139 : errhint("Remove this referential integrity trigger and its mates, then do ALTER TABLE ADD CONSTRAINT.")));
2140 :
2141 : /* Find or create a hashtable entry for the constraint */
2142 10890 : riinfo = ri_LoadConstraintInfo(constraintOid);
2143 :
2144 : /* Do some easy cross-checks against the trigger call data */
2145 10890 : if (rel_is_pk)
2146 : {
2147 4264 : if (riinfo->fk_relid != trigger->tgconstrrelid ||
2148 4264 : riinfo->pk_relid != RelationGetRelid(trig_rel))
2149 0 : elog(ERROR, "wrong pg_constraint entry for trigger \"%s\" on table \"%s\"",
2150 : trigger->tgname, RelationGetRelationName(trig_rel));
2151 : }
2152 : else
2153 : {
2154 6626 : if (riinfo->fk_relid != RelationGetRelid(trig_rel) ||
2155 6626 : riinfo->pk_relid != trigger->tgconstrrelid)
2156 0 : elog(ERROR, "wrong pg_constraint entry for trigger \"%s\" on table \"%s\"",
2157 : trigger->tgname, RelationGetRelationName(trig_rel));
2158 : }
2159 :
2160 10890 : if (riinfo->confmatchtype != FKCONSTR_MATCH_FULL &&
2161 10426 : riinfo->confmatchtype != FKCONSTR_MATCH_PARTIAL &&
2162 10426 : riinfo->confmatchtype != FKCONSTR_MATCH_SIMPLE)
2163 0 : elog(ERROR, "unrecognized confmatchtype: %d",
2164 : riinfo->confmatchtype);
2165 :
2166 10890 : if (riinfo->confmatchtype == FKCONSTR_MATCH_PARTIAL)
2167 0 : ereport(ERROR,
2168 : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2169 : errmsg("MATCH PARTIAL not yet implemented")));
2170 :
2171 10890 : return riinfo;
2172 : }
2173 :
2174 : /*
2175 : * Fetch or create the RI_ConstraintInfo struct for an FK constraint.
2176 : */
2177 : static const RI_ConstraintInfo *
2178 10890 : ri_LoadConstraintInfo(Oid constraintOid)
2179 : {
2180 : RI_ConstraintInfo *riinfo;
2181 : bool found;
2182 : HeapTuple tup;
2183 : Form_pg_constraint conForm;
2184 :
2185 : /*
2186 : * On the first call initialize the hashtable
2187 : */
2188 10890 : if (!ri_constraint_cache)
2189 422 : ri_InitHashTables();
2190 :
2191 : /*
2192 : * Find or create a hash entry. If we find a valid one, just return it.
2193 : */
2194 10890 : riinfo = (RI_ConstraintInfo *) hash_search(ri_constraint_cache,
2195 : &constraintOid,
2196 : HASH_ENTER, &found);
2197 10890 : if (!found)
2198 3844 : riinfo->valid = false;
2199 7046 : else if (riinfo->valid)
2200 6734 : return riinfo;
2201 :
2202 : /*
2203 : * Fetch the pg_constraint row so we can fill in the entry.
2204 : */
2205 4156 : tup = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constraintOid));
2206 4156 : if (!HeapTupleIsValid(tup)) /* should not happen */
2207 0 : elog(ERROR, "cache lookup failed for constraint %u", constraintOid);
2208 4156 : conForm = (Form_pg_constraint) GETSTRUCT(tup);
2209 :
2210 4156 : if (conForm->contype != CONSTRAINT_FOREIGN) /* should not happen */
2211 0 : elog(ERROR, "constraint %u is not a foreign key constraint",
2212 : constraintOid);
2213 :
2214 : /* And extract data */
2215 : Assert(riinfo->constraint_id == constraintOid);
2216 4156 : if (OidIsValid(conForm->conparentid))
2217 1434 : riinfo->constraint_root_id =
2218 1434 : get_ri_constraint_root(conForm->conparentid);
2219 : else
2220 2722 : riinfo->constraint_root_id = constraintOid;
2221 4156 : riinfo->oidHashValue = GetSysCacheHashValue1(CONSTROID,
2222 : ObjectIdGetDatum(constraintOid));
2223 4156 : riinfo->rootHashValue = GetSysCacheHashValue1(CONSTROID,
2224 : ObjectIdGetDatum(riinfo->constraint_root_id));
2225 4156 : memcpy(&riinfo->conname, &conForm->conname, sizeof(NameData));
2226 4156 : riinfo->pk_relid = conForm->confrelid;
2227 4156 : riinfo->fk_relid = conForm->conrelid;
2228 4156 : riinfo->confupdtype = conForm->confupdtype;
2229 4156 : riinfo->confdeltype = conForm->confdeltype;
2230 4156 : riinfo->confmatchtype = conForm->confmatchtype;
2231 4156 : riinfo->hasperiod = conForm->conperiod;
2232 :
2233 4156 : DeconstructFkConstraintRow(tup,
2234 : &riinfo->nkeys,
2235 4156 : riinfo->fk_attnums,
2236 4156 : riinfo->pk_attnums,
2237 4156 : riinfo->pf_eq_oprs,
2238 4156 : riinfo->pp_eq_oprs,
2239 4156 : riinfo->ff_eq_oprs,
2240 : &riinfo->ndelsetcols,
2241 4156 : riinfo->confdelsetcols);
2242 :
2243 : /*
2244 : * For temporal FKs, get the operators and functions we need. We ask the
2245 : * opclass of the PK element for these. This all gets cached (as does the
2246 : * generated plan), so there's no performance issue.
2247 : */
2248 4156 : if (riinfo->hasperiod)
2249 : {
2250 254 : Oid opclass = get_index_column_opclass(conForm->conindid, riinfo->nkeys);
2251 :
2252 254 : FindFKPeriodOpers(opclass,
2253 : &riinfo->period_contained_by_oper,
2254 : &riinfo->agged_period_contained_by_oper);
2255 : }
2256 :
2257 4156 : ReleaseSysCache(tup);
2258 :
2259 : /*
2260 : * For efficient processing of invalidation messages below, we keep a
2261 : * doubly-linked count list of all currently valid entries.
2262 : */
2263 4156 : dclist_push_tail(&ri_constraint_cache_valid_list, &riinfo->valid_link);
2264 :
2265 4156 : riinfo->valid = true;
2266 :
2267 4156 : return riinfo;
2268 : }
2269 :
2270 : /*
2271 : * get_ri_constraint_root
2272 : * Returns the OID of the constraint's root parent
2273 : */
2274 : static Oid
2275 1756 : get_ri_constraint_root(Oid constrOid)
2276 : {
2277 : for (;;)
2278 322 : {
2279 : HeapTuple tuple;
2280 : Oid constrParentOid;
2281 :
2282 1756 : tuple = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constrOid));
2283 1756 : if (!HeapTupleIsValid(tuple))
2284 0 : elog(ERROR, "cache lookup failed for constraint %u", constrOid);
2285 1756 : constrParentOid = ((Form_pg_constraint) GETSTRUCT(tuple))->conparentid;
2286 1756 : ReleaseSysCache(tuple);
2287 1756 : if (!OidIsValid(constrParentOid))
2288 1434 : break; /* we reached the root constraint */
2289 322 : constrOid = constrParentOid;
2290 : }
2291 1434 : return constrOid;
2292 : }
2293 :
2294 : /*
2295 : * Callback for pg_constraint inval events
2296 : *
2297 : * While most syscache callbacks just flush all their entries, pg_constraint
2298 : * gets enough update traffic that it's probably worth being smarter.
2299 : * Invalidate any ri_constraint_cache entry associated with the syscache
2300 : * entry with the specified hash value, or all entries if hashvalue == 0.
2301 : *
2302 : * Note: at the time a cache invalidation message is processed there may be
2303 : * active references to the cache. Because of this we never remove entries
2304 : * from the cache, but only mark them invalid, which is harmless to active
2305 : * uses. (Any query using an entry should hold a lock sufficient to keep that
2306 : * data from changing under it --- but we may get cache flushes anyway.)
2307 : */
2308 : static void
2309 68950 : InvalidateConstraintCacheCallBack(Datum arg, int cacheid, uint32 hashvalue)
2310 : {
2311 : dlist_mutable_iter iter;
2312 :
2313 : Assert(ri_constraint_cache != NULL);
2314 :
2315 : /*
2316 : * If the list of currently valid entries gets excessively large, we mark
2317 : * them all invalid so we can empty the list. This arrangement avoids
2318 : * O(N^2) behavior in situations where a session touches many foreign keys
2319 : * and also does many ALTER TABLEs, such as a restore from pg_dump.
2320 : */
2321 68950 : if (dclist_count(&ri_constraint_cache_valid_list) > 1000)
2322 0 : hashvalue = 0; /* pretend it's a cache reset */
2323 :
2324 254650 : dclist_foreach_modify(iter, &ri_constraint_cache_valid_list)
2325 : {
2326 185700 : RI_ConstraintInfo *riinfo = dclist_container(RI_ConstraintInfo,
2327 : valid_link, iter.cur);
2328 :
2329 : /*
2330 : * We must invalidate not only entries directly matching the given
2331 : * hash value, but also child entries, in case the invalidation
2332 : * affects a root constraint.
2333 : */
2334 185700 : if (hashvalue == 0 ||
2335 185642 : riinfo->oidHashValue == hashvalue ||
2336 183118 : riinfo->rootHashValue == hashvalue)
2337 : {
2338 2828 : riinfo->valid = false;
2339 : /* Remove invalidated entries from the list, too */
2340 2828 : dclist_delete_from(&ri_constraint_cache_valid_list, iter.cur);
2341 : }
2342 : }
2343 68950 : }
2344 :
2345 :
2346 : /*
2347 : * Prepare execution plan for a query to enforce an RI restriction
2348 : */
2349 : static SPIPlanPtr
2350 3494 : ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
2351 : RI_QueryKey *qkey, Relation fk_rel, Relation pk_rel)
2352 : {
2353 : SPIPlanPtr qplan;
2354 : Relation query_rel;
2355 : Oid save_userid;
2356 : int save_sec_context;
2357 :
2358 : /*
2359 : * Use the query type code to determine whether the query is run against
2360 : * the PK or FK table; we'll do the check as that table's owner
2361 : */
2362 3494 : if (qkey->constr_queryno <= RI_PLAN_LAST_ON_PK)
2363 2664 : query_rel = pk_rel;
2364 : else
2365 830 : query_rel = fk_rel;
2366 :
2367 : /* Switch to proper UID to perform check as */
2368 3494 : GetUserIdAndSecContext(&save_userid, &save_sec_context);
2369 3494 : SetUserIdAndSecContext(RelationGetForm(query_rel)->relowner,
2370 : save_sec_context | SECURITY_LOCAL_USERID_CHANGE |
2371 : SECURITY_NOFORCE_RLS);
2372 :
2373 : /* Create the plan */
2374 3494 : qplan = SPI_prepare(querystr, nargs, argtypes);
2375 :
2376 3494 : if (qplan == NULL)
2377 0 : elog(ERROR, "SPI_prepare returned %s for %s", SPI_result_code_string(SPI_result), querystr);
2378 :
2379 : /* Restore UID and security context */
2380 3494 : SetUserIdAndSecContext(save_userid, save_sec_context);
2381 :
2382 : /* Save the plan */
2383 3494 : SPI_keepplan(qplan);
2384 3494 : ri_HashPreparedPlan(qkey, qplan);
2385 :
2386 3494 : return qplan;
2387 : }
2388 :
2389 : /*
2390 : * Perform a query to enforce an RI restriction
2391 : */
2392 : static bool
2393 6930 : ri_PerformCheck(const RI_ConstraintInfo *riinfo,
2394 : RI_QueryKey *qkey, SPIPlanPtr qplan,
2395 : Relation fk_rel, Relation pk_rel,
2396 : TupleTableSlot *oldslot, TupleTableSlot *newslot,
2397 : bool is_restrict,
2398 : bool detectNewRows, int expect_OK)
2399 : {
2400 : Relation query_rel,
2401 : source_rel;
2402 : bool source_is_pk;
2403 : Snapshot test_snapshot;
2404 : Snapshot crosscheck_snapshot;
2405 : int limit;
2406 : int spi_result;
2407 : Oid save_userid;
2408 : int save_sec_context;
2409 : Datum vals[RI_MAX_NUMKEYS * 2];
2410 : char nulls[RI_MAX_NUMKEYS * 2];
2411 :
2412 : /*
2413 : * Use the query type code to determine whether the query is run against
2414 : * the PK or FK table; we'll do the check as that table's owner
2415 : */
2416 6930 : if (qkey->constr_queryno <= RI_PLAN_LAST_ON_PK)
2417 5188 : query_rel = pk_rel;
2418 : else
2419 1742 : query_rel = fk_rel;
2420 :
2421 : /*
2422 : * The values for the query are taken from the table on which the trigger
2423 : * is called - it is normally the other one with respect to query_rel. An
2424 : * exception is ri_Check_Pk_Match(), which uses the PK table for both (and
2425 : * sets queryno to RI_PLAN_CHECK_LOOKUPPK_FROM_PK). We might eventually
2426 : * need some less klugy way to determine this.
2427 : */
2428 6930 : if (qkey->constr_queryno == RI_PLAN_CHECK_LOOKUPPK)
2429 : {
2430 4150 : source_rel = fk_rel;
2431 4150 : source_is_pk = false;
2432 : }
2433 : else
2434 : {
2435 2780 : source_rel = pk_rel;
2436 2780 : source_is_pk = true;
2437 : }
2438 :
2439 : /* Extract the parameters to be passed into the query */
2440 6930 : if (newslot)
2441 : {
2442 4354 : ri_ExtractValues(source_rel, newslot, riinfo, source_is_pk,
2443 : vals, nulls);
2444 4354 : if (oldslot)
2445 204 : ri_ExtractValues(source_rel, oldslot, riinfo, source_is_pk,
2446 204 : vals + riinfo->nkeys, nulls + riinfo->nkeys);
2447 : }
2448 : else
2449 : {
2450 2576 : ri_ExtractValues(source_rel, oldslot, riinfo, source_is_pk,
2451 : vals, nulls);
2452 : }
2453 :
2454 : /*
2455 : * In READ COMMITTED mode, we just need to use an up-to-date regular
2456 : * snapshot, and we will see all rows that could be interesting. But in
2457 : * transaction-snapshot mode, we can't change the transaction snapshot. If
2458 : * the caller passes detectNewRows == false then it's okay to do the query
2459 : * with the transaction snapshot; otherwise we use a current snapshot, and
2460 : * tell the executor to error out if it finds any rows under the current
2461 : * snapshot that wouldn't be visible per the transaction snapshot. Note
2462 : * that SPI_execute_snapshot will register the snapshots, so we don't need
2463 : * to bother here.
2464 : */
2465 6930 : if (IsolationUsesXactSnapshot() && detectNewRows)
2466 : {
2467 32 : CommandCounterIncrement(); /* be sure all my own work is visible */
2468 32 : test_snapshot = GetLatestSnapshot();
2469 32 : crosscheck_snapshot = GetTransactionSnapshot();
2470 : }
2471 : else
2472 : {
2473 : /* the default SPI behavior is okay */
2474 6898 : test_snapshot = InvalidSnapshot;
2475 6898 : crosscheck_snapshot = InvalidSnapshot;
2476 : }
2477 :
2478 : /*
2479 : * If this is a select query (e.g., for a 'no action' or 'restrict'
2480 : * trigger), we only need to see if there is a single row in the table,
2481 : * matching the key. Otherwise, limit = 0 - because we want the query to
2482 : * affect ALL the matching rows.
2483 : */
2484 6930 : limit = (expect_OK == SPI_OK_SELECT) ? 1 : 0;
2485 :
2486 : /* Switch to proper UID to perform check as */
2487 6930 : GetUserIdAndSecContext(&save_userid, &save_sec_context);
2488 6930 : SetUserIdAndSecContext(RelationGetForm(query_rel)->relowner,
2489 : save_sec_context | SECURITY_LOCAL_USERID_CHANGE |
2490 : SECURITY_NOFORCE_RLS);
2491 :
2492 : /* Finally we can run the query. */
2493 6930 : spi_result = SPI_execute_snapshot(qplan,
2494 : vals, nulls,
2495 : test_snapshot, crosscheck_snapshot,
2496 : false, false, limit);
2497 :
2498 : /* Restore UID and security context */
2499 6916 : SetUserIdAndSecContext(save_userid, save_sec_context);
2500 :
2501 : /* Check result */
2502 6916 : if (spi_result < 0)
2503 0 : elog(ERROR, "SPI_execute_snapshot returned %s", SPI_result_code_string(spi_result));
2504 :
2505 6916 : if (expect_OK >= 0 && spi_result != expect_OK)
2506 0 : ereport(ERROR,
2507 : (errcode(ERRCODE_INTERNAL_ERROR),
2508 : errmsg("referential integrity query on \"%s\" from constraint \"%s\" on \"%s\" gave unexpected result",
2509 : RelationGetRelationName(pk_rel),
2510 : NameStr(riinfo->conname),
2511 : RelationGetRelationName(fk_rel)),
2512 : errhint("This is most likely due to a rule having rewritten the query.")));
2513 :
2514 : /* XXX wouldn't it be clearer to do this part at the caller? */
2515 6916 : if (qkey->constr_queryno != RI_PLAN_CHECK_LOOKUPPK_FROM_PK &&
2516 5270 : expect_OK == SPI_OK_SELECT &&
2517 5270 : (SPI_processed == 0) == (qkey->constr_queryno == RI_PLAN_CHECK_LOOKUPPK))
2518 1040 : ri_ReportViolation(riinfo,
2519 : pk_rel, fk_rel,
2520 : newslot ? newslot : oldslot,
2521 : NULL,
2522 : qkey->constr_queryno, is_restrict, false);
2523 :
2524 5876 : return SPI_processed != 0;
2525 : }
2526 :
2527 : /*
2528 : * Extract fields from a tuple into Datum/nulls arrays
2529 : */
2530 : static void
2531 7134 : ri_ExtractValues(Relation rel, TupleTableSlot *slot,
2532 : const RI_ConstraintInfo *riinfo, bool rel_is_pk,
2533 : Datum *vals, char *nulls)
2534 : {
2535 : const int16 *attnums;
2536 : bool isnull;
2537 :
2538 7134 : if (rel_is_pk)
2539 2984 : attnums = riinfo->pk_attnums;
2540 : else
2541 4150 : attnums = riinfo->fk_attnums;
2542 :
2543 16960 : for (int i = 0; i < riinfo->nkeys; i++)
2544 : {
2545 9826 : vals[i] = slot_getattr(slot, attnums[i], &isnull);
2546 9826 : nulls[i] = isnull ? 'n' : ' ';
2547 : }
2548 7134 : }
2549 :
2550 : /*
2551 : * Produce an error report
2552 : *
2553 : * If the failed constraint was on insert/update to the FK table,
2554 : * we want the key names and values extracted from there, and the error
2555 : * message to look like 'key blah is not present in PK'.
2556 : * Otherwise, the attr names and values come from the PK table and the
2557 : * message looks like 'key blah is still referenced from FK'.
2558 : */
2559 : static void
2560 1124 : ri_ReportViolation(const RI_ConstraintInfo *riinfo,
2561 : Relation pk_rel, Relation fk_rel,
2562 : TupleTableSlot *violatorslot, TupleDesc tupdesc,
2563 : int queryno, bool is_restrict, bool partgone)
2564 : {
2565 : StringInfoData key_names;
2566 : StringInfoData key_values;
2567 : bool onfk;
2568 : const int16 *attnums;
2569 : Oid rel_oid;
2570 : AclResult aclresult;
2571 1124 : bool has_perm = true;
2572 :
2573 : /*
2574 : * Determine which relation to complain about. If tupdesc wasn't passed
2575 : * by caller, assume the violator tuple came from there.
2576 : */
2577 1124 : onfk = (queryno == RI_PLAN_CHECK_LOOKUPPK);
2578 1124 : if (onfk)
2579 : {
2580 594 : attnums = riinfo->fk_attnums;
2581 594 : rel_oid = fk_rel->rd_id;
2582 594 : if (tupdesc == NULL)
2583 544 : tupdesc = fk_rel->rd_att;
2584 : }
2585 : else
2586 : {
2587 530 : attnums = riinfo->pk_attnums;
2588 530 : rel_oid = pk_rel->rd_id;
2589 530 : if (tupdesc == NULL)
2590 496 : tupdesc = pk_rel->rd_att;
2591 : }
2592 :
2593 : /*
2594 : * Check permissions- if the user does not have access to view the data in
2595 : * any of the key columns then we don't include the errdetail() below.
2596 : *
2597 : * Check if RLS is enabled on the relation first. If so, we don't return
2598 : * any specifics to avoid leaking data.
2599 : *
2600 : * Check table-level permissions next and, failing that, column-level
2601 : * privileges.
2602 : *
2603 : * When a partition at the referenced side is being detached/dropped, we
2604 : * needn't check, since the user must be the table owner anyway.
2605 : */
2606 1124 : if (partgone)
2607 34 : has_perm = true;
2608 1090 : else if (check_enable_rls(rel_oid, InvalidOid, true) != RLS_ENABLED)
2609 : {
2610 1084 : aclresult = pg_class_aclcheck(rel_oid, GetUserId(), ACL_SELECT);
2611 1084 : if (aclresult != ACLCHECK_OK)
2612 : {
2613 : /* Try for column-level permissions */
2614 0 : for (int idx = 0; idx < riinfo->nkeys; idx++)
2615 : {
2616 0 : aclresult = pg_attribute_aclcheck(rel_oid, attnums[idx],
2617 : GetUserId(),
2618 : ACL_SELECT);
2619 :
2620 : /* No access to the key */
2621 0 : if (aclresult != ACLCHECK_OK)
2622 : {
2623 0 : has_perm = false;
2624 0 : break;
2625 : }
2626 : }
2627 : }
2628 : }
2629 : else
2630 6 : has_perm = false;
2631 :
2632 1124 : if (has_perm)
2633 : {
2634 : /* Get printable versions of the keys involved */
2635 1118 : initStringInfo(&key_names);
2636 1118 : initStringInfo(&key_values);
2637 2800 : for (int idx = 0; idx < riinfo->nkeys; idx++)
2638 : {
2639 1682 : int fnum = attnums[idx];
2640 1682 : Form_pg_attribute att = TupleDescAttr(tupdesc, fnum - 1);
2641 : char *name,
2642 : *val;
2643 : Datum datum;
2644 : bool isnull;
2645 :
2646 1682 : name = NameStr(att->attname);
2647 :
2648 1682 : datum = slot_getattr(violatorslot, fnum, &isnull);
2649 1682 : if (!isnull)
2650 : {
2651 : Oid foutoid;
2652 : bool typisvarlena;
2653 :
2654 1682 : getTypeOutputInfo(att->atttypid, &foutoid, &typisvarlena);
2655 1682 : val = OidOutputFunctionCall(foutoid, datum);
2656 : }
2657 : else
2658 0 : val = "null";
2659 :
2660 1682 : if (idx > 0)
2661 : {
2662 564 : appendStringInfoString(&key_names, ", ");
2663 564 : appendStringInfoString(&key_values, ", ");
2664 : }
2665 1682 : appendStringInfoString(&key_names, name);
2666 1682 : appendStringInfoString(&key_values, val);
2667 : }
2668 : }
2669 :
2670 1124 : if (partgone)
2671 34 : ereport(ERROR,
2672 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
2673 : errmsg("removing partition \"%s\" violates foreign key constraint \"%s\"",
2674 : RelationGetRelationName(pk_rel),
2675 : NameStr(riinfo->conname)),
2676 : errdetail("Key (%s)=(%s) is still referenced from table \"%s\".",
2677 : key_names.data, key_values.data,
2678 : RelationGetRelationName(fk_rel)),
2679 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
2680 1090 : else if (onfk)
2681 594 : ereport(ERROR,
2682 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
2683 : errmsg("insert or update on table \"%s\" violates foreign key constraint \"%s\"",
2684 : RelationGetRelationName(fk_rel),
2685 : NameStr(riinfo->conname)),
2686 : has_perm ?
2687 : errdetail("Key (%s)=(%s) is not present in table \"%s\".",
2688 : key_names.data, key_values.data,
2689 : RelationGetRelationName(pk_rel)) :
2690 : errdetail("Key is not present in table \"%s\".",
2691 : RelationGetRelationName(pk_rel)),
2692 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
2693 496 : else if (is_restrict)
2694 90 : ereport(ERROR,
2695 : (errcode(ERRCODE_RESTRICT_VIOLATION),
2696 : errmsg("update or delete on table \"%s\" violates RESTRICT setting of foreign key constraint \"%s\" on table \"%s\"",
2697 : RelationGetRelationName(pk_rel),
2698 : NameStr(riinfo->conname),
2699 : RelationGetRelationName(fk_rel)),
2700 : has_perm ?
2701 : errdetail("Key (%s)=(%s) is referenced from table \"%s\".",
2702 : key_names.data, key_values.data,
2703 : RelationGetRelationName(fk_rel)) :
2704 : errdetail("Key is referenced from table \"%s\".",
2705 : RelationGetRelationName(fk_rel)),
2706 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
2707 : else
2708 406 : ereport(ERROR,
2709 : (errcode(ERRCODE_FOREIGN_KEY_VIOLATION),
2710 : errmsg("update or delete on table \"%s\" violates foreign key constraint \"%s\" on table \"%s\"",
2711 : RelationGetRelationName(pk_rel),
2712 : NameStr(riinfo->conname),
2713 : RelationGetRelationName(fk_rel)),
2714 : has_perm ?
2715 : errdetail("Key (%s)=(%s) is still referenced from table \"%s\".",
2716 : key_names.data, key_values.data,
2717 : RelationGetRelationName(fk_rel)) :
2718 : errdetail("Key is still referenced from table \"%s\".",
2719 : RelationGetRelationName(fk_rel)),
2720 : errtableconstraint(fk_rel, NameStr(riinfo->conname))));
2721 : }
2722 :
2723 :
2724 : /*
2725 : * ri_NullCheck -
2726 : *
2727 : * Determine the NULL state of all key values in a tuple
2728 : *
2729 : * Returns one of RI_KEYS_ALL_NULL, RI_KEYS_NONE_NULL or RI_KEYS_SOME_NULL.
2730 : */
2731 : static int
2732 7982 : ri_NullCheck(TupleDesc tupDesc,
2733 : TupleTableSlot *slot,
2734 : const RI_ConstraintInfo *riinfo, bool rel_is_pk)
2735 : {
2736 : const int16 *attnums;
2737 7982 : bool allnull = true;
2738 7982 : bool nonenull = true;
2739 :
2740 7982 : if (rel_is_pk)
2741 2440 : attnums = riinfo->pk_attnums;
2742 : else
2743 5542 : attnums = riinfo->fk_attnums;
2744 :
2745 18554 : for (int i = 0; i < riinfo->nkeys; i++)
2746 : {
2747 10572 : if (slot_attisnull(slot, attnums[i]))
2748 534 : nonenull = false;
2749 : else
2750 10038 : allnull = false;
2751 : }
2752 :
2753 7982 : if (allnull)
2754 258 : return RI_KEYS_ALL_NULL;
2755 :
2756 7724 : if (nonenull)
2757 7520 : return RI_KEYS_NONE_NULL;
2758 :
2759 204 : return RI_KEYS_SOME_NULL;
2760 : }
2761 :
2762 :
2763 : /*
2764 : * ri_InitHashTables -
2765 : *
2766 : * Initialize our internal hash tables.
2767 : */
2768 : static void
2769 422 : ri_InitHashTables(void)
2770 : {
2771 : HASHCTL ctl;
2772 :
2773 422 : ctl.keysize = sizeof(Oid);
2774 422 : ctl.entrysize = sizeof(RI_ConstraintInfo);
2775 422 : ri_constraint_cache = hash_create("RI constraint cache",
2776 : RI_INIT_CONSTRAINTHASHSIZE,
2777 : &ctl, HASH_ELEM | HASH_BLOBS);
2778 :
2779 : /* Arrange to flush cache on pg_constraint changes */
2780 422 : CacheRegisterSyscacheCallback(CONSTROID,
2781 : InvalidateConstraintCacheCallBack,
2782 : (Datum) 0);
2783 :
2784 422 : ctl.keysize = sizeof(RI_QueryKey);
2785 422 : ctl.entrysize = sizeof(RI_QueryHashEntry);
2786 422 : ri_query_cache = hash_create("RI query cache",
2787 : RI_INIT_QUERYHASHSIZE,
2788 : &ctl, HASH_ELEM | HASH_BLOBS);
2789 :
2790 422 : ctl.keysize = sizeof(RI_CompareKey);
2791 422 : ctl.entrysize = sizeof(RI_CompareHashEntry);
2792 422 : ri_compare_cache = hash_create("RI compare cache",
2793 : RI_INIT_QUERYHASHSIZE,
2794 : &ctl, HASH_ELEM | HASH_BLOBS);
2795 422 : }
2796 :
2797 :
2798 : /*
2799 : * ri_FetchPreparedPlan -
2800 : *
2801 : * Lookup for a query key in our private hash table of prepared
2802 : * and saved SPI execution plans. Return the plan if found or NULL.
2803 : */
2804 : static SPIPlanPtr
2805 6930 : ri_FetchPreparedPlan(RI_QueryKey *key)
2806 : {
2807 : RI_QueryHashEntry *entry;
2808 : SPIPlanPtr plan;
2809 :
2810 : /*
2811 : * On the first call initialize the hashtable
2812 : */
2813 6930 : if (!ri_query_cache)
2814 0 : ri_InitHashTables();
2815 :
2816 : /*
2817 : * Lookup for the key
2818 : */
2819 6930 : entry = (RI_QueryHashEntry *) hash_search(ri_query_cache,
2820 : key,
2821 : HASH_FIND, NULL);
2822 6930 : if (entry == NULL)
2823 3074 : return NULL;
2824 :
2825 : /*
2826 : * Check whether the plan is still valid. If it isn't, we don't want to
2827 : * simply rely on plancache.c to regenerate it; rather we should start
2828 : * from scratch and rebuild the query text too. This is to cover cases
2829 : * such as table/column renames. We depend on the plancache machinery to
2830 : * detect possible invalidations, though.
2831 : *
2832 : * CAUTION: this check is only trustworthy if the caller has already
2833 : * locked both FK and PK rels.
2834 : */
2835 3856 : plan = entry->plan;
2836 3856 : if (plan && SPI_plan_is_valid(plan))
2837 3436 : return plan;
2838 :
2839 : /*
2840 : * Otherwise we might as well flush the cached plan now, to free a little
2841 : * memory space before we make a new one.
2842 : */
2843 420 : entry->plan = NULL;
2844 420 : if (plan)
2845 420 : SPI_freeplan(plan);
2846 :
2847 420 : return NULL;
2848 : }
2849 :
2850 :
2851 : /*
2852 : * ri_HashPreparedPlan -
2853 : *
2854 : * Add another plan to our private SPI query plan hashtable.
2855 : */
2856 : static void
2857 3494 : ri_HashPreparedPlan(RI_QueryKey *key, SPIPlanPtr plan)
2858 : {
2859 : RI_QueryHashEntry *entry;
2860 : bool found;
2861 :
2862 : /*
2863 : * On the first call initialize the hashtable
2864 : */
2865 3494 : if (!ri_query_cache)
2866 0 : ri_InitHashTables();
2867 :
2868 : /*
2869 : * Add the new plan. We might be overwriting an entry previously found
2870 : * invalid by ri_FetchPreparedPlan.
2871 : */
2872 3494 : entry = (RI_QueryHashEntry *) hash_search(ri_query_cache,
2873 : key,
2874 : HASH_ENTER, &found);
2875 : Assert(!found || entry->plan == NULL);
2876 3494 : entry->plan = plan;
2877 3494 : }
2878 :
2879 :
2880 : /*
2881 : * ri_KeysEqual -
2882 : *
2883 : * Check if all key values in OLD and NEW are "equivalent":
2884 : * For normal FKs we check for equality.
2885 : * For temporal FKs we check that the PK side is a superset of its old value,
2886 : * or the FK side is a subset of its old value.
2887 : *
2888 : * Note: at some point we might wish to redefine this as checking for
2889 : * "IS NOT DISTINCT" rather than "=", that is, allow two nulls to be
2890 : * considered equal. Currently there is no need since all callers have
2891 : * previously found at least one of the rows to contain no nulls.
2892 : */
2893 : static bool
2894 2308 : ri_KeysEqual(Relation rel, TupleTableSlot *oldslot, TupleTableSlot *newslot,
2895 : const RI_ConstraintInfo *riinfo, bool rel_is_pk)
2896 : {
2897 : const int16 *attnums;
2898 :
2899 2308 : if (rel_is_pk)
2900 1508 : attnums = riinfo->pk_attnums;
2901 : else
2902 800 : attnums = riinfo->fk_attnums;
2903 :
2904 : /* XXX: could be worthwhile to fetch all necessary attrs at once */
2905 3692 : for (int i = 0; i < riinfo->nkeys; i++)
2906 : {
2907 : Datum oldvalue;
2908 : Datum newvalue;
2909 : bool isnull;
2910 :
2911 : /*
2912 : * Get one attribute's oldvalue. If it is NULL - they're not equal.
2913 : */
2914 2692 : oldvalue = slot_getattr(oldslot, attnums[i], &isnull);
2915 2692 : if (isnull)
2916 1308 : return false;
2917 :
2918 : /*
2919 : * Get one attribute's newvalue. If it is NULL - they're not equal.
2920 : */
2921 2662 : newvalue = slot_getattr(newslot, attnums[i], &isnull);
2922 2662 : if (isnull)
2923 0 : return false;
2924 :
2925 2662 : if (rel_is_pk)
2926 : {
2927 : /*
2928 : * If we are looking at the PK table, then do a bytewise
2929 : * comparison. We must propagate PK changes if the value is
2930 : * changed to one that "looks" different but would compare as
2931 : * equal using the equality operator. This only makes a
2932 : * difference for ON UPDATE CASCADE, but for consistency we treat
2933 : * all changes to the PK the same.
2934 : */
2935 1808 : CompactAttribute *att = TupleDescCompactAttr(oldslot->tts_tupleDescriptor, attnums[i] - 1);
2936 :
2937 1808 : if (!datum_image_eq(oldvalue, newvalue, att->attbyval, att->attlen))
2938 972 : return false;
2939 : }
2940 : else
2941 : {
2942 : Oid eq_opr;
2943 :
2944 : /*
2945 : * When comparing the PERIOD columns we can skip the check
2946 : * whenever the referencing column stayed equal or shrank, so test
2947 : * with the contained-by operator instead.
2948 : */
2949 854 : if (riinfo->hasperiod && i == riinfo->nkeys - 1)
2950 48 : eq_opr = riinfo->period_contained_by_oper;
2951 : else
2952 806 : eq_opr = riinfo->ff_eq_oprs[i];
2953 :
2954 : /*
2955 : * For the FK table, compare with the appropriate equality
2956 : * operator. Changes that compare equal will still satisfy the
2957 : * constraint after the update.
2958 : */
2959 854 : if (!ri_CompareWithCast(eq_opr, RIAttType(rel, attnums[i]), RIAttCollation(rel, attnums[i]),
2960 : newvalue, oldvalue))
2961 306 : return false;
2962 : }
2963 : }
2964 :
2965 1000 : return true;
2966 : }
2967 :
2968 :
2969 : /*
2970 : * ri_CompareWithCast -
2971 : *
2972 : * Call the appropriate comparison operator for two values.
2973 : * Normally this is equality, but for the PERIOD part of foreign keys
2974 : * it is ContainedBy, so the order of lhs vs rhs is significant.
2975 : * See below for how the collation is applied.
2976 : *
2977 : * NB: we have already checked that neither value is null.
2978 : */
2979 : static bool
2980 854 : ri_CompareWithCast(Oid eq_opr, Oid typeid, Oid collid,
2981 : Datum lhs, Datum rhs)
2982 : {
2983 854 : RI_CompareHashEntry *entry = ri_HashCompareOp(eq_opr, typeid);
2984 :
2985 : /* Do we need to cast the values? */
2986 854 : if (OidIsValid(entry->cast_func_finfo.fn_oid))
2987 : {
2988 12 : lhs = FunctionCall3(&entry->cast_func_finfo,
2989 : lhs,
2990 : Int32GetDatum(-1), /* typmod */
2991 : BoolGetDatum(false)); /* implicit coercion */
2992 12 : rhs = FunctionCall3(&entry->cast_func_finfo,
2993 : rhs,
2994 : Int32GetDatum(-1), /* typmod */
2995 : BoolGetDatum(false)); /* implicit coercion */
2996 : }
2997 :
2998 : /*
2999 : * Apply the comparison operator.
3000 : *
3001 : * Note: This function is part of a call stack that determines whether an
3002 : * update to a row is significant enough that it needs checking or action
3003 : * on the other side of a foreign-key constraint. Therefore, the
3004 : * comparison here would need to be done with the collation of the *other*
3005 : * table. For simplicity (e.g., we might not even have the other table
3006 : * open), we'll use our own collation. This is fine because we require
3007 : * that both collations have the same notion of equality (either they are
3008 : * both deterministic or else they are both the same).
3009 : *
3010 : * With range/multirangetypes, the collation of the base type is stored as
3011 : * part of the rangetype (pg_range.rngcollation), and always used, so
3012 : * there is no danger of inconsistency even using a non-equals operator.
3013 : * But if we support arbitrary types with PERIOD, we should perhaps just
3014 : * always force a re-check.
3015 : */
3016 854 : return DatumGetBool(FunctionCall2Coll(&entry->eq_opr_finfo, collid, lhs, rhs));
3017 : }
3018 :
3019 : /*
3020 : * ri_HashCompareOp -
3021 : *
3022 : * See if we know how to compare two values, and create a new hash entry
3023 : * if not.
3024 : */
3025 : static RI_CompareHashEntry *
3026 854 : ri_HashCompareOp(Oid eq_opr, Oid typeid)
3027 : {
3028 : RI_CompareKey key;
3029 : RI_CompareHashEntry *entry;
3030 : bool found;
3031 :
3032 : /*
3033 : * On the first call initialize the hashtable
3034 : */
3035 854 : if (!ri_compare_cache)
3036 0 : ri_InitHashTables();
3037 :
3038 : /*
3039 : * Find or create a hash entry. Note we're assuming RI_CompareKey
3040 : * contains no struct padding.
3041 : */
3042 854 : key.eq_opr = eq_opr;
3043 854 : key.typeid = typeid;
3044 854 : entry = (RI_CompareHashEntry *) hash_search(ri_compare_cache,
3045 : &key,
3046 : HASH_ENTER, &found);
3047 854 : if (!found)
3048 292 : entry->valid = false;
3049 :
3050 : /*
3051 : * If not already initialized, do so. Since we'll keep this hash entry
3052 : * for the life of the backend, put any subsidiary info for the function
3053 : * cache structs into TopMemoryContext.
3054 : */
3055 854 : if (!entry->valid)
3056 : {
3057 : Oid lefttype,
3058 : righttype,
3059 : castfunc;
3060 : CoercionPathType pathtype;
3061 :
3062 : /* We always need to know how to call the equality operator */
3063 292 : fmgr_info_cxt(get_opcode(eq_opr), &entry->eq_opr_finfo,
3064 : TopMemoryContext);
3065 :
3066 : /*
3067 : * If we chose to use a cast from FK to PK type, we may have to apply
3068 : * the cast function to get to the operator's input type.
3069 : *
3070 : * XXX eventually it would be good to support array-coercion cases
3071 : * here and in ri_CompareWithCast(). At the moment there is no point
3072 : * because cases involving nonidentical array types will be rejected
3073 : * at constraint creation time.
3074 : *
3075 : * XXX perhaps also consider supporting CoerceViaIO? No need at the
3076 : * moment since that will never be generated for implicit coercions.
3077 : */
3078 292 : op_input_types(eq_opr, &lefttype, &righttype);
3079 : Assert(lefttype == righttype);
3080 292 : if (typeid == lefttype)
3081 268 : castfunc = InvalidOid; /* simplest case */
3082 : else
3083 : {
3084 24 : pathtype = find_coercion_pathway(lefttype, typeid,
3085 : COERCION_IMPLICIT,
3086 : &castfunc);
3087 24 : if (pathtype != COERCION_PATH_FUNC &&
3088 : pathtype != COERCION_PATH_RELABELTYPE)
3089 : {
3090 : /*
3091 : * The declared input type of the eq_opr might be a
3092 : * polymorphic type such as ANYARRAY or ANYENUM, or other
3093 : * special cases such as RECORD; find_coercion_pathway
3094 : * currently doesn't subsume these special cases.
3095 : */
3096 18 : if (!IsBinaryCoercible(typeid, lefttype))
3097 0 : elog(ERROR, "no conversion function from %s to %s",
3098 : format_type_be(typeid),
3099 : format_type_be(lefttype));
3100 : }
3101 : }
3102 292 : if (OidIsValid(castfunc))
3103 6 : fmgr_info_cxt(castfunc, &entry->cast_func_finfo,
3104 : TopMemoryContext);
3105 : else
3106 286 : entry->cast_func_finfo.fn_oid = InvalidOid;
3107 292 : entry->valid = true;
3108 : }
3109 :
3110 854 : return entry;
3111 : }
3112 :
3113 :
3114 : /*
3115 : * Given a trigger function OID, determine whether it is an RI trigger,
3116 : * and if so whether it is attached to PK or FK relation.
3117 : */
3118 : int
3119 8252 : RI_FKey_trigger_type(Oid tgfoid)
3120 : {
3121 8252 : switch (tgfoid)
3122 : {
3123 3028 : case F_RI_FKEY_CASCADE_DEL:
3124 : case F_RI_FKEY_CASCADE_UPD:
3125 : case F_RI_FKEY_RESTRICT_DEL:
3126 : case F_RI_FKEY_RESTRICT_UPD:
3127 : case F_RI_FKEY_SETNULL_DEL:
3128 : case F_RI_FKEY_SETNULL_UPD:
3129 : case F_RI_FKEY_SETDEFAULT_DEL:
3130 : case F_RI_FKEY_SETDEFAULT_UPD:
3131 : case F_RI_FKEY_NOACTION_DEL:
3132 : case F_RI_FKEY_NOACTION_UPD:
3133 3028 : return RI_TRIGGER_PK;
3134 :
3135 2474 : case F_RI_FKEY_CHECK_INS:
3136 : case F_RI_FKEY_CHECK_UPD:
3137 2474 : return RI_TRIGGER_FK;
3138 : }
3139 :
3140 2750 : return RI_TRIGGER_NONE;
3141 : }
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